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Sample records for central incisors based

  1. Lengths of the maxillary central incisor, the nasal bone, and the anterior cranial base in different skeletal malocclusions

    DEFF Research Database (Denmark)

    Arntsen, Torill; Kjær, Inger; Sonnesen, Liselotte

    2009-01-01

    with neutral occlusion and normal craniofacial morphology (n=39). Two-way ANOVA tests were used to evaluate differences in lengths between groups and gender. Results. Statistically shorter maxillary central incisor length was found in the open bite group (p

  2. The primary Maxillary Central Incisor in the Solitary Median Maxillary Central Incisor syndrome

    DEFF Research Database (Denmark)

    Kjaer, I; Balslev-Olesen, M

    2012-01-01

    Solitary Median Maxillary Central Incisor (SMMCI) is a developmental anomaly in the permanent dentition with one single central incisor in the maxilla, positioned exactly in the midline. This condition has been associated with extra- and intraoral malformations in the frontonasal segment of the c...

  3. Solitary median maxillary central incisor (SMMCI) syndrome

    OpenAIRE

    Hall Roger K

    2006-01-01

    Abstract Solitary median maxillary central incisor syndrome (SMMCI) is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s) operating in utero about the 35th–38th day(s) from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F) at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; i...

  4. Solitary Median Maxillary Central Incisor Versus Agenesis of the Maxillary Central Incisor.

    Science.gov (United States)

    de Carvalho, Fabrício Kitazono; Arid, Juliana; De Rossi, Andiara; Paula-Silva, Francisco W G; Nelson-Filho, Paulo

    2016-01-01

    A solitary median maxillary central incisor (SMMCI) is rare and affected individuals may carry a potentially serious condition known as SMMCI syndrome. However, many of these cases do not receive proper attention because they are misdiagnosed as agenesis of the maxillary central incisor. The purpose of this manuscript is to report two cases of children with only one maxillary central incisor and draw diagnostic differences between the entities. A correct diagnosis is very important because if an SMMCI is confirmed, the patient should be referred for genetic counseling. PMID:27098718

  5. Two root canals in maxillary central incisor

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    Fábio de Almeida Gomes

    2011-07-01

    Full Text Available Introduction and objective: The success of endodontic treatment requires the knowledge of tooth morphology and its variations. Case report: This clinical article reports an unusual root canal configuration that was detected in a maxillary central incisor with two root canals, demonstrated by radiographic and computerized tomography exams. Conclusion: Knowledge of endodontic anatomy as well as the obtainment of both preoperative radiographs and tomography is important to detect abnormal tooth morphology.

  6. Interceptive management of winged maxillary central incisors

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    Mamta Dali

    2013-01-01

    Full Text Available Introduction: Winged maxillary incisors are a well-recognized clinical finding, which can result in psychological trauma to children at growing age. Interceptive treatment is usually carried out in mixed dentition period in order to reduce the severity of a developing malocclusion in future. Case Report: This paper reports a case of 6-years-old female patient with winged maxillary central incisor being treated with derotation technique using the beggs brackets along with nance palatal arch space maintainer. Discussion: The major advantages in carrying out this treatment with fixed brackets are the ease with which the force magnitude and vector can be controlled much more precisely than with a removable appliance, minimal discomfort to the patient and reduces the need for patient co-operation.

  7. Extraction of Maxillary Central Incisors: An Orthodontic-Restorative Treatment

    OpenAIRE

    Zohreh Hedayati; Maryam Zare; Fateme Bahramnia

    2014-01-01

    Malformed central incisors with poor prognosis could be candidates for extraction especially in crowded dental arches. This case report refers to a 12-year-old boy who suffered from malformed upper central incisors associated with severe attrition. Upper lateral incisors were positioned palatally and canines were rotated and positioned in the high buccal area. The patient had class II malocclusion and space deficiency in both dental arches. Due to incisal wear and malformed short maxillary ce...

  8. Brain malformation in single median maxillary central incisor

    DEFF Research Database (Denmark)

    Kjaer, I; Wagner, Aa; Thomsen, L L;

    2009-01-01

    Clinical and radiographic examinations and MR scan of a 12-year-old girl with SMMCI (single median maxillary central incisor) showed impaired growth and a midline defect involving the central incisor, cranium and the midline structures in the brain, falx cerebri and pituitary gland. She had a...

  9. Age estimation using maxillary central incisors: A radiographic study

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    Nitin Agarwal

    2012-01-01

    Full Text Available Background: In the field of forensic dentistry, secondary changes in teeth with advancing age have been used as reliable predictors of age in various studies. Aim: The purpose of the present study was to present a method for assessing the chronological age based on the relationship between age and morphological parameters of maxillary central incisors. Materials and Methods: Fifty subjects between 20-70 years of age were included in the study. Intraoral periapical radiographs were taken in relation to maxillary central incisors using paralleling technique. The following measurements were recorded: lengths of tooth, pulp, root and width of root and pulp at three different points. Regression formulas were used to calculate the dental age. Results: The mean estimated age showed no statistically significant difference from the actual mean age (P > 0.05. Also, maximum difference was seen for root length variable (-1.035 ± 1.86 years.

  10. Solitary median maxillary central incisor (SMMCI) syndrome.

    Science.gov (United States)

    Hall, Roger K

    2006-01-01

    Solitary median maxillary central incisor syndrome (SMMCI) is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s) operating in utero about the 35th-38th day(s) from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F) at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis) is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. Diagnosis should be made by eight months of age, but can be made at birth and even prenatally at 18-22 weeks from the routine mid-trimester ultrasound scan. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. SMMCI tooth itself is mainly an aesthetic problem, which is ideally managed by combined orthodontic, prosthodontic and oral surgical treatment; alternatively, it can be left untreated. PMID:16722608

  11. Solitary median maxillary central incisor (SMMCI syndrome

    Directory of Open Access Journals (Sweden)

    Hall Roger K

    2006-04-01

    Full Text Available Abstract Solitary median maxillary central incisor syndrome (SMMCI is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s operating in utero about the 35th–38th day(s from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. Diagnosis should be made by eight months of age, but can be made at birth and even prenatally at 18–22 weeks from the routine mid-trimester ultrasound scan. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. SMMCI tooth itself is mainly an aesthetic problem, which is ideally managed by combined orthodontic, prosthodontic and oral surgical treatment; alternatively, it can be left untreated.

  12. Review of Dilaceration of Maxillary Central Incisor: A Mutidisciplinary Challenge.

    Science.gov (United States)

    Walia, Pawanjit Singh; Rohilla, Ajit Kumar; Choudhary, Shweta; Kaur, Ravneet

    2016-01-01

    Traumatic injuries to primary dentition may interfere with the development of permanent dentition. Among the many malformations, dilaceration is particularly important to the clinician. Management of dilacerated maxillary central incisor requires a multidisciplinary approach. The main purpose of this review is to present the etiological factors, the mechanism, clinical features, radiographic features and treatment of dilaceration of the maxillary central incisors. How to cite this article: Walia PS, Rohilla AK, Choudhary S, Kaur R. Review of Dilaceration of Maxillary Central Incisor: A Multidisciplinary Challenge. Int J Clin Pediatr Dent 2016;9(1):90-98.

  13. Extraction of Maxillary Central Incisors: An Orthodontic-Restorative Treatment

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    Zohreh Hedayati

    2014-01-01

    Full Text Available Malformed central incisors with poor prognosis could be candidates for extraction especially in crowded dental arches. This case report refers to a 12-year-old boy who suffered from malformed upper central incisors associated with severe attrition. Upper lateral incisors were positioned palatally and canines were rotated and positioned in the high buccal area. The patient had class II malocclusion and space deficiency in both dental arches. Due to incisal wear and malformed short maxillary central incisors and the need for root canal therapy with a major crown build-up, these teeth were extracted. The maxillary lateral incisors were substituted. Thus the maxillary canines were substituted for lateral incisors and the first premolars were substituted for canines. In the lower dental arch the first bicuspids were extracted. Composite resin build-up was performed on the maxillary lateral incisors and canines. This allowed for the crowding and the malocclusion to be corrected. Subsequent gingivectomy improved the patient's gingival margins and smile esthetics one month after orthodontic therapy.

  14. Esthetic periodontal surgery for impacted dilacerated maxillary central incisors.

    Science.gov (United States)

    Wei, Yu-Ju; Lin, Yi-Chun; Kaung, Shou-Shin; Yang, Shue-Fen; Lee, Shyh-Yuan; Lai, Yu-Lin

    2012-10-01

    Clinicians do not frequently see impacted dilacerated maxillary incisors in their patients. When they do, there are several diagnostic and management challenges for correcting root dilacerations. An unfavorable esthetic outcome might occur as a result of soft-tissue complications during surgical eruption procedures. We present 2 patients with an impacted and dilacerated maxillary central incisor. Computed tomography scans with 3-dimensional reformation were used to accurately assess the positions of the dilacerated teeth, the degree of dilaceration, and the stage of root formation. The therapy primarily involved 2-stage crown exposure surgery combined with orthodontic traction. An apicoectomy was performed on 1 dilacerated tooth; the other exhibited pulp vitality. This article highlights the periodontal surgical strategies for the esthetic management of inverted crowns. Through periodontal plastic surgery and interdisciplinary cooperation, the impacted dilacerated central incisors were properly aligned, and successful esthetic results were achieved. PMID:22999678

  15. Solitary median maxillary central incisor: a report of 2 cases.

    Science.gov (United States)

    Sekerci, Ahmet Ercan; Uçar, Faruk Izzet; Gümüş, Hüsniye; Aydınbelge, Mustafa; Sisman, Yildiray

    2012-01-01

    A single median maxillary central incisor (SMMCI) is a rare dental anomaly that may occur alone or be associated with growth deficiency or other systemic abnormalities. The best known association is with holoprosencephaly (HPE). HPE is a complex brain malformation that affects both the forebrain and the face. Early diagnosis of SMMCI is important, since it may be a sign of other severe congenital or developmental abnormalities. Therefore, systematic follow-up and close monitoring of the growth and development of SMMCI patients is crucial. The purpose of this paper was to report the cases of 2 children, each with a single median maxillary central incisor, and describe important symptoms of this syndrome that have not yet been reported. PMID:22583889

  16. A maxillary central incisor with four root canals

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    Fábio de Almeida-Gomes

    2012-01-01

    Full Text Available The objective of the present study is to present a case report of endodontic treatment of a maxillary central incisor with 1 root and 4 root canals. The success of endodontic treatment requires knowledge of dental anatomy and its variations. This clinical article reports an unusual anatomy detected in a maxillary central incisor with 4 root canals with an associated periapical lesion. The incidence of 4 root canals in this tooth is rare. However, it must be taken into consideration, the clinical and radiographic evaluations during the endodontic treatment in order to enhance the diagnostic. Many times, the presence of a supernumerary canal is noticed only after canal treatment due to continuing post-operative discomfort or treatment failure.

  17. [Two cases of solitary median maxillary central incisor syndrome].

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    Catania, P; Conti, C; Poggi, G M; Bardelli, T; Lasagni, D; De Martino, M

    2010-02-01

    Solitary median maxillary central incisor syndrome (SMMCI) syndrome is a unique developmental abnormality arising from an unknown event occurring between the 35th and 38th days in utero, and involving mieline structure of the head including the cranial bones, the maxilla and its container dentition (specifically the central incisor tooth germ), together with other midline structures of the body. The SMMCI tooth may be possibly occur as an isolated trait or in association with many other midline developmental anomalies. It is estimated to occur in 1:50000 live births. There is a wide variability in the phenotypic spectrum. SMMCI is considered one of the most minimal expressions of the holoprosencephaly spectrum. Mutation in the Sonic Hedgehog homolog (SHH) gene may be associated with SSMMCI, but recent studies suggests the existence of several other candidate genes. We described two patients with SMMCI. They presented a solitary median maxillary incisor, short stature, hipotelorism and corpus callosus anomalies found on magnetic resonance imaging (MRI). They also present severe hiponatremia. At the best of our knowledge, this is the first report of cases of SMMCI with hiponatremia. We suggest that the sodium disorder may be secondary to syndrome of inappropriate secretion of antidiuretic hormone (SIADH). PMID:20212404

  18. Eruption age of permanent mandibular first molars and central incisors in the south Indian population

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    Gupta Rakhi

    2007-01-01

    Full Text Available Objective: The existing eruption schedules for permanent and deciduous dentition are based on studies in the Western population. Since Indians differ from Westerners racially, genetically, and environmentally, these studies fail to provide relevant guidance on the eruption schedule in the Indian population. This study aims at determining the eruption pattern of permanent mandibular molars and central incisors in the south Indian population. Materials and Methods: 10,156 apparently healthy Indian children in the age-group of 6-9 years were examined with mouth mirror and probe under adequate illumination for the status of the eruption of the permanent mandibular first molar and permanent mandibular central incisor. Pearson′s Chi-square test with Yates′ continuity correction was used to calculate the P -value for comparison of proportion between girls and boys. The values obtained in our study were compared with the standard values. The Z-test with continuity correction was used to calculate the P -value. Results: As per our study, the permanent mandibular first molars and central incisors erupted one to two years later compared to the values reported in Westerners. The earlier eruption of the permanent mandibular first molars compared to the permanent mandibular central incisors, as well as the earlier eruption of both the teeth in girls compared to boys, were in accordance with the existing literature. Conclusion: The eruption age reported by us may form a standard reference for eruption age in Indians.

  19. Maxillary Central Incisor with Two Roots: A Case Report

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    L. Khojastehpour

    2005-06-01

    Full Text Available A 16 year old female was referred to an oral and maxillofacial radiologist for evaluation of a radiolucent area at mesial radicular aspect of right maxillary central incisor which was detected accidentally during pre-orthodontic treatment check ups. Clinicalexamination showed no particular signs or symptoms except for slightly tenderness to lateral percussion. Second radiograph with altered horizontal angulations showed a mesial supernumerary root which the radiolucency seemed to be associated with that. Inorder to treat the tooth, the composite filling was removed and canals were cleaned,shaped, and obturated by lateral condensation technique.

  20. Solitary median maxillary central incisor: A case report of a rare dental anomaly

    OpenAIRE

    Deepak Chandrasekaran; Arif Yezdani; Faizal Tajir; B. Saravanan; Rajasekar, L.

    2015-01-01

    The solitary median maxillary central incisor (SMMCI) syndrome is a rare dental anomaly and has an incidence of 1:50,000 live births. In SMMCI, there is only one central incisor present, and it develops exactly at the midline. SMMCI occurrence has been described with growth hormone deficiency or other structural anomalies in the midline of the body. In this case, the 8-year-old female patient reported a single median maxillary central incisor with missing maxillary and mandibular frena, with ...

  1. Investigation of Vertical Distance between Incisive Papilla and Incisal Edge of Maxillary Central Incisors

    OpenAIRE

    Guldag, M. Ustun; Sentut, Fatih; Buyukkaplan, U. Sebnem

    2008-01-01

    Objectives The aim of the present study was to determine the vertical distance between maxillary central incisors and incisive papilla. Methods The vertical distance between incisal edges of maxillary central incisors and the centre of the incisive papilla was measured by a digital caliper on the stone casts that were obtained from dentate subjects. Results The mean vertical distance between maxillary central incisors and incisive papilla on the stone casts was 6.70±0.81 mm. The vertical dist...

  2. A central incisor with 4 independent root canals: a case report

    NARCIS (Netherlands)

    C. Aznar Portoles; A.T. Moinzadeh; H. Shemesh

    2015-01-01

    The maxillary central incisor is the tooth with the least anatomic variations. Despite the fact that several studies have reported a prevalence of 100% for the presence of a single canal, root canal aberrations of maxillary central incisors with up to 3 canals have also been reported. Such cases rep

  3. [Solitary median maxillary central incisor syndrome:a case of report].

    Science.gov (United States)

    Kang, Li-ying; Liu, Xin-qiang

    2014-04-01

    Solitary median maxillary central incisor (SMMCI) is a rare dental anomaly characterized by a symmetric central incisor of normal size, developed and erupted precisely in the midline of the maxilla in both primary and permanent dentitions. SMMCI may occur alone or be associated with other midline structures defects of the body or other systemic disorders. The best known association is holoprosencephaly (HPE). This paper reported a case of SMMCI that companied with other midline structures defects of the body. PMID:24935855

  4. Managing the severely proclined maxillary anteriors by extracting traumatized right maxillary central incisor

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    Mahesh Jain

    2014-01-01

    Full Text Available A 14-year-old girl reported with severely proclined maxillary anterior teeth with fractured and discolored right maxillary central incisor with questionable prognosis. Autotransplantation of premolar to replace central incisor was considered a risky option as patient was 14-year-old with presence of advanced root development of premolar. The immediate placement of the prosthetic implant was also not possible because of patient′s age. Therefore, it was decided to use the space obtained by extracting questionable maxillary right central incisor for orthodontic purpose and also sacrificing the healthy premolar is invariably an excessive biological cost for a modest functional and aesthetic gain. Hence, the treatment plan for this case includes extraction of right maxillary central incisor and left maxillary first premolar, movement of right maxillary lateral incisor mesially, achieving normal axial inclination of maxillary anteriors with normal overjet and overbite. Mandibular arch was treated nonextraction due to congenitally missing central incisors with presence of normally inclined lower anteriors thereby maintaining Angles class I occlusion. Tipping, usually, seen in Begg mechanotherapy was used for our advantage to correct severely proclined maxillary anteriors with simultaneous bite opening mechanics. Case was completed in 19 months and posttreatment records including photographs, radiographs and study models were made. Begg wrap around the retainer was placed in the maxillary arch allowing natural settling of occlusion.

  5. Clinical and radiographic evaluation of maxillary central incisors exposure in patients undergoing maxillary advancement

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    Guilherme dos Santos Trento

    2015-12-01

    Full Text Available Abstract Introduction: Patients with dentofacial deformities may undergo orthodontic or orthodontic-surgical treatment. Both modalities can affect esthetics. Objective: This study aims to evaluate clinical and radiographic changes in exposure of maxillary central incisors occurring after orthognathic surgery for maxillary advancement. Methods: A total of 17 patients who underwent orthognathic surgery for maxillary advancement between September, 2010 and July, 2011 were selected. Exposure of maxillary central incisors was evaluated clinically and by lateral cephalograms. Measurements were taken one week before and three months after surgery. Data were paired in terms of sex, age, nasolabial angle, height and thickness of the upper lip, the amount of maxillary advancement, clinical exposure and inclination of maxillary central incisor by statistical tests (CI 95%. Results: After maxillary advancement, incisor clinical exposure had increased even with relaxed lips and under forced smile. Moreover, there was a mean increase of 23.33% revealed by lateral cephalograms. There was an inverse correlation between upper lip thickness and incisors postsurgical exposure revealed by radiographic images (p = 0.002. Conclusions: Significant changes in the exposure of maxillary central incisors occur after maxillary advancement, under the influence of some factors, especially lip thickness.

  6. Stress Analysis of a Maxillary Central Incisor Restored with Different Posts

    OpenAIRE

    Adanir, Necdet; Belli, Sema

    2007-01-01

    Objectives To evaluate the effects of different post materials on the stress distribution in an endodontically treated maxillary incisor. Materials and Methods A pseudo 3-dimensional finite element model was created in a labiolingual cross-sectional view of a maxillary central incisor and modified according to five posts with different physical properties consisting stainless steel, titanium, gold alloy, glass fiber (Snowpost), and carbon fiber (Composipost). A 200 N force was then applied fr...

  7. Orthodontic Management of a Severely Rotated Maxillary Central Incisor in the Mixed Dentition: A Case Report

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    Arezoo Jahanbin

    2014-06-01

    Full Text Available The aim of this case report was to introduce an appliance for correcting severe rotation of anterior teeth in the mixed dentition period. A 9-year-old Iranian boy with a mixed dentition Class I malocclusion complained of a severely rotated of upper right central incisor. There was a mesiodens between the central incisors. The supernumerary tooth was first extracted and then a Whip appliance which is composed of a removable plate, a cantilever spring and a central bracket on the rotated tooth was utilized. After 8 months, the upper right central incisor was orthodontically brought into proper alignment. Circumferential supracrestal fibrotomy was performed on the overcorrected tooth. One week after surgery, the device was removed and the retention was started. The whip appliance is a removable appliance that can effectively correct severe rotation of anterior teeth especially during the mixed dentition period.

  8. Solitary median maxillary central incisor: A case report of a rare dental anomaly

    Directory of Open Access Journals (Sweden)

    Deepak Chandrasekaran

    2015-01-01

    Full Text Available The solitary median maxillary central incisor (SMMCI syndrome is a rare dental anomaly and has an incidence of 1:50,000 live births. In SMMCI, there is only one central incisor present, and it develops exactly at the midline. SMMCI occurrence has been described with growth hormone deficiency or other structural anomalies in the midline of the body. In this case, the 8-year-old female patient reported a single median maxillary central incisor with missing maxillary and mandibular frena, with apparently no other abnormalities. Early diagnosis and recognition of SMMCI are important for all practicing Orthodontists, as it may be a sign of other severe congenital or developmental abnormalities.

  9. Solitary median maxillary central incisor: A case report of a rare dental anomaly.

    Science.gov (United States)

    Chandrasekaran, Deepak; Yezdani, Arif; Tajir, Faizal; Saravanan, B; Rajasekar, L

    2015-04-01

    The solitary median maxillary central incisor (SMMCI) syndrome is a rare dental anomaly and has an incidence of 1:50,000 live births. In SMMCI, there is only one central incisor present, and it develops exactly at the midline. SMMCI occurrence has been described with growth hormone deficiency or other structural anomalies in the midline of the body. In this case, the 8-year-old female patient reported a single median maxillary central incisor with missing maxillary and mandibular frena, with apparently no other abnormalities. Early diagnosis and recognition of SMMCI are important for all practicing Orthodontists, as it may be a sign of other severe congenital or developmental abnormalities. PMID:26015739

  10. Solitary median maxillary central incisor, short stature, choanal atresia/midnasal stenosis (SMMCI) syndrome.

    Science.gov (United States)

    Hall, R K; Bankier, A; Aldred, M J; Kan, K; Lucas, J O; Perks, A G

    1997-12-01

    This article describes a series of 21 consecutive cases, each involving a solitary median maxillary central incisor; the patients were seen in the Department of Dentistry or the Victorian Clinical Genetics Unit, Murdoch Institute, at the Royal Children's Hospital, Melbourne, from 1966 to 1997. The spectrum of anomalies and associated features present in these cases--solitary median maxillary central incisor, choanal atresia, and holoprosencephaly--is described, and the literature related to the features, including genetic studies in these conditions, is reviewed. We relate our findings in these cases to current knowledge of developmental embryology. It is hoped that the findings, together with our interpretation of them, will help to clarify understanding of solitary median maxillary central incisor syndrome. This syndrome was previously considered a simple midline defect of the dental lamina, but it is now recognized as a possible predictor of holoprosencephalies of varying degrees in the proband, in members of the proband's family, and in the family's descendants. PMID:9431535

  11. Bilateral presence of two root canals in maxillary central incisors: A rare case study

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    M Kavitha

    2014-01-01

    Full Text Available Success in root canal treatment is achieved after thorough cleaning and shaping followed by complete obturation of the canal system. Therefore, endodontic therapy requires specific and complete knowledge of the internal and external dental anatomy, and its variations in presentation. The internal anatomy of the maxillary central incisor is well-known and usually presents one root canal system. This case report describes an endodontic treatment of traumatized both maxillary central incisors with two canal systems. Knowledge of dental anatomy is fundamental for proper endodontic practice. When root canal treatment is performed, the clinician should be aware that both external and internal anatomy may be abnormal.

  12. Bilateral presence of two root canals in maxillary central incisors: A rare case study.

    Science.gov (United States)

    Kavitha, M; Gokul, Kannan; Ramaprabha, B; Lakshmi, Amudha

    2014-04-01

    Success in root canal treatment is achieved after thorough cleaning and shaping followed by complete obturation of the canal system. Therefore, endodontic therapy requires specific and complete knowledge of the internal and external dental anatomy, and its variations in presentation. The internal anatomy of the maxillary central incisor is well-known and usually presents one root canal system. This case report describes an endodontic treatment of traumatized both maxillary central incisors with two canal systems. Knowledge of dental anatomy is fundamental for proper endodontic practice. When root canal treatment is performed, the clinician should be aware that both external and internal anatomy may be abnormal.

  13. Endocrine and anatomical findings in a case of Solitary Median Maxillary Central Incisor Syndrome.

    Science.gov (United States)

    Szakszon, Katalin; Felszeghy, Enikő; Csízy, István; Józsa, Tamás; Káposzta, Rita; Balogh, Erzsébet; Oláh, Eva; Balogh, István; Berényi, Ervin; Knegt, Alida C; Ilyés, István

    2012-02-01

    Solitary Median Maxillary Central Incisor Syndrome (SMMCI) is a rare malformation syndrome consisting of multiple, mainly midline defects. Some authors suggest that it is a mild manifestation of the wide spectrum of holoprosencephaly, others classify it rather as a distinct entity. Authors report a case of SMMCI presenting with growth retardation, mild intellectual disability and absence of puberty. Cytogenetic and molecular cytogenetic investigations could identify no abnormalities. The presence of a single maxillary incisor called for further investigations to clarify hidden anomalies, these were empty sella, panhypopituitarism, hypothyroidism, and hypoplasia of the inner genitals. Based on the above findings, growth hormone, estrogen, and L-thyroxine substitution was introduced, which resulted in satisfactory longitudinal growth and onset of sexual maturation. We suggest genetic counselling and if needed, invasive investigations in female patients with short stature and absent/delayed puberty, with or without sex chromosomal anomalies, as the adequate therapy and even the quality of life of patient depends largely on the knowledge of their anatomical and endocrine status. PMID:22138217

  14. Stress prediction in a central incisor with intra-radicular restorations

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    Martha Vasconcellos Amarante

    2011-01-01

    Full Text Available A 2D finite element analysis was applied to calculate shear and von Mises equivalent stresses developed, under masticatory loading, in an upper central incisor restored with cast gold post and carbon fiber reinforced epoxy resin post. Based on the predicted shear stress levels, it is concluded that the gold post model is more prone to shear failure along the post-dentin interface. Whereas shear stress concentration also occurs in both models at the core-crown interface, the stress level predicted there is higher for the carbon fiber post model which would be more susceptible to crown displacement. Finally, the prediction of von Mises equivalent stress indicates a non-uniform distribution, with the stress preferentially concentrated in the gold post along its interface with the tooth dentin. For the carbon fiber post restored model, on the other hand, the von Mises stresses are more uniformly distributed achieving its maximum level in the tooth dentin.

  15. Solitary median maxillary central incisor in association with Goldenhar's syndrome: a case report.

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    Garcia de Paula e Silva, Francisco Wanderley; de Carvalho, Fabricio Kitazono; Diaz-Serrano, Kranya Victória; de Freitas, Aldevina Campos; Borsatto, Maria Cristina; de Queiroz, Alexandra Mussolino

    2007-01-01

    Goldenhar's syndrome is a rare disorder characterized by several anomalies that include dermal epibulbar cysts, auricular appendices and malformations and vertebral anomalies. In this article, the authors report a case of Goldenhar's syndrome in a 10-year-old child who presented with the classical signs of this condition and a solitary median maxillary central incisor (SMMCI). PMID:17658185

  16. Correlation between maxillary central incisor crown morphology and mandibular dental arch form in normal occlusion subjects.

    Science.gov (United States)

    Paranhos, Luiz Renato; Lima, Carolina Souto; da Silva, Ricardo Henrique Alves; Daruge Júnior, Eduardo; Torres, Fernando Cesar

    2012-01-01

    The aim of this study was to evaluate the correlation between the morphology of the mandibular dental arch and the maxillary central incisor crown. Cast models from 51 Caucasian individuals, older than 15 years, with optimal occlusion, no previous orthodontic treatment, featuring 4 of the 6 keys to normal occlusion by Andrews (the first being mandatory) were observed. The models were digitalized using a 3D scanner, and images of the maxillary central incisor and mandibular dental arch were obtained. These were printed and placed in an album below pre-set models of arches and dental crowns, and distributed to 12 dental surgeons, who were asked to choose which shape was most in accordance with the models and crown presented. The Kappa test was performed to evaluate the concordance among evaluators while the chi-square test was used to verify the association between the dental arch and central incisor morphology, at a 5% significance level. The Kappa test showed moderate agreement among evaluators for both variables of this study, and the chi-square test showed no significant association between tooth shape and mandibular dental arch morphology. It may be concluded that the use of arch morphology as a diagnostic method to determine the shape of the maxillary central incisor is not appropriate. Further research is necessary to assess tooth shape using a stricter scientific basis. PMID:22666773

  17. Treatment of severe rotations of maxillary central incisors with whip appliance: Report of three cases

    Directory of Open Access Journals (Sweden)

    Iman Parisay

    2014-01-01

    Full Text Available The routine treatment for rotated maxillary incisor is a fixed appliance, but in some instance the use of this method is impossible. In addition, in only limited cases of rotation, removable appliance is applicable. In this study, the use of a semi-removable appliance is presented, which has some benefits over the other methods. In this study, the corrections of about 70-90° rotation of the maxillary central incisors in different phases of mixed dentition were performed in three patients using whip appliance. This method was performed using a simple removable appliance such as Hawley appliance and whip spring that forced the couple to derotate the tooth. In all cases, treatment was successfully completed in relative short duration. Whip appliance can be recommended as an effective method to correct rotation of maxillary incisor in mixed dentition with several advantages like rapid correction.

  18. Crowns to create esthetics for mal-aligned central incisors: a case report.

    Science.gov (United States)

    Savadi, Ravindra C; Savadi, Anupama R; Kumar, Preeti Satheesh

    2011-06-01

    This case report describes the smile design of crowded upper central anteriors in a female patient aged 25 years. The patient wanted the correction to be completed in a short period of time. A smile design schedule was drawn up involving root canal treatment of the central incisors and placing posts in both the teeth. All ceramic crowns were then fabricated to establish a very satisfactory and pleasing esthetics.

  19. DiGeorge syndrome associated with solitary median maxillary central incisor.

    Science.gov (United States)

    Yang, Huai-Chih; Shyur, Shyh-Dar; Huang, Li-Hsin; Chang, Yi-Chi; Wen, Da-Chin; Liang, Pei-Hsuan; Lin, Mao-Tsair

    2005-01-01

    DiGeorge syndrome is a primary immunodeficiency disease characterized by dysgenesis of the thymus and parathyroid glands, conotruncal cardiac anomalies, and other dysmorphic features. Although most patients have a common microscopic deletion in chromosome 22q11.2, marked clinical variability exists. A solitary median maxillary central incisor (SMMCI) is a rare dental anomaly which may be an isolated occurrence or associated with congenital nasal airway abnormalities or holoprosencephaly. We report a patient with DiGeorge syndrome who was diagnosed at nearly 1 month of age and was later found to have a solitary median central incisor. Initially, the patient presented with recurrent episodes of respiratory distress attributed to partial airway obstruction, one of the phenotypic features of SMMCI. A fluorescence in situ hybridization study showed a chromosome 22q11.2 deletion. PMID:16252847

  20. Solitary median maxillary central incisor syndrome associated with unique cleft palate: a rare case report.

    Science.gov (United States)

    Holla, Goda; Ramakrishna, Yeluri; Holla, Anup; Munshi, Autar Krishen

    2014-01-01

    Solitary median maxillary central incisor (SMMCI) syndrome is a rare dental anomaly that affects 1:50,000 live births. SMMCI syndrome is characterized by the presence of a single central incisor located on the maxillary midline in both primary and permanent dentitions. It may occur as an isolated finding or in association with developmental defects and systemic involvement. Congenital anomalies associated with SMMCI syndrome can include short stature, mild forms of deviation in craniofacial morphology, mild to severe intellectual disability, congenital heart disease, and cleft lip and/or palate. This report describes a clinical case of a 7-year-old girl with SMMCI syndrome--in addition to bilateral residual cleft and associated nasal regurgitation--that was treated with a removable maxillary obturator. PMID:24598504

  1. Compound odontoma associated with mandibular impacted permanent central incisor: a case report

    Directory of Open Access Journals (Sweden)

    Ugur Gurer

    2012-04-01

    Full Text Available

    Odontomas are the most common benign odontogenic tumors that are hamartomas composed of various dental tissues, and there are two types, complex and compound. Compound odontomas are more prevalent than complex odontomas and consist of many teeth–like structures. Most of such lesions are asymptomatic. These lesions are generally diagnosed by routine radiological examination. The compound type is generally found in the anterior region of the maxilla. The etiology of these lesions has not been precisely explained. If there is absence of any contraindication, the treatment for odontomas is surgical excision.

    This article describes a case of compound odontoma associated with impacted central mandibular right permanent incisor in a 12–year–old female due to trauma. The odontoma was surgically removed with an impacted central incisor.

  2. Rare Root Morphology of a Maxillary Central Incisor Associated With Gingival Hyperplasia

    Science.gov (United States)

    Monea, Monica; Moldovan, Cosmin

    2016-01-01

    Abstract Dilaceration is a developmental disturbance characterized by the angulation of the crown or root of a permanent tooth, which is often related to trauma of primary dentition. We report a case of a dilacerated root in a maxillary central incisor associated with gingival hyperplasia in a patient under fixed orthodontic treatment, a combination of pathological conditions that had never been mentioned before in the scientific literature. A 10-year-old female patient presented to the Department of Odontology and Oral Pathology with tenderness to palpation and bleeding from the oral aspect of the central incisor, alerted by the proliferation of the gingiva. During clinical examination, the palpation performed with a dental probe revealed a carious lesion with dental pulp exposure on the distal aspect of right central incisor and the presence of a sessile mass of inflamed gingival tissue that proliferated inside the defect. On the preoperative radiograph a dilacerated root canal was noted, without periapical bone resorption. The main diagnosis was irreversible pulpitis and gingival hyperplasia and the treatment option was surgical removal of the inflamed tissue with histopathological examination and root canal treatment. Successful endodontic treatment with a good prognosis was recorded. The measurement of the root curvature proved to be extremely helpful in choosing the right endodontic technique and made the treatment easier than expected. An important observation was that, despite the rare clinical and radiographic aspect of this dilacerated tooth, the endodontic treatment proved to be relatively easy to perform and, therefore, the prognosis was considered favorable. PMID:27149498

  3. Rare Root Morphology of a Maxillary Central Incisor Associated With Gingival Hyperplasia: An Endodontic Case Report.

    Science.gov (United States)

    Monea, Monica; Moldovan, Cosmin

    2016-05-01

    Dilaceration is a developmental disturbance characterized by the angulation of the crown or root of a permanent tooth, which is often related to trauma of primary dentition. We report a case of a dilacerated root in a maxillary central incisor associated with gingival hyperplasia in a patient under fixed orthodontic treatment, a combination of pathological conditions that had never been mentioned before in the scientific literature.A 10-year-old female patient presented to the Department of Odontology and Oral Pathology with tenderness to palpation and bleeding from the oral aspect of the central incisor, alerted by the proliferation of the gingiva. During clinical examination, the palpation performed with a dental probe revealed a carious lesion with dental pulp exposure on the distal aspect of right central incisor and the presence of a sessile mass of inflamed gingival tissue that proliferated inside the defect. On the preoperative radiograph a dilacerated root canal was noted, without periapical bone resorption.The main diagnosis was irreversible pulpitis and gingival hyperplasia and the treatment option was surgical removal of the inflamed tissue with histopathological examination and root canal treatment. Successful endodontic treatment with a good prognosis was recorded.The measurement of the root curvature proved to be extremely helpful in choosing the right endodontic technique and made the treatment easier than expected. An important observation was that, despite the rare clinical and radiographic aspect of this dilacerated tooth, the endodontic treatment proved to be relatively easy to perform and, therefore, the prognosis was considered favorable.

  4. Ferrule Designs and Stress Distribution in Endodontically Treated Upper Central Incisors: 3D Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    A. Hassan Ahangari

    2008-09-01

    Full Text Available Objective: The main goal of this study was to evaluate stress distribution of endodonti-cally treated maxillary central incisors restored with glass fiber posts, composite resin cores, and crowns with different ferrule designs.Materials and Methods: Four three-dimensional models of a maxillary central incisor were modeled in SolidWorks 2006. Tooth with no ferrule, tooth with a 2 mm circumferen-tial ferrule, tooth with a 2 mm beveled ferrule and tooth with a 0.5 mm circumferential ferrule. The teeth were restored with glass fiber posts, composite resin cores, and full ce-ramics crowns. Each model was loaded (1 N on the palatal side at an angle of 45 degrees to tooth long axis. Von Mises stress findings along the inner surface of the root canals were assessed and compared.Results: The Von Mises Stress at CEJ was the highest in the model without a ferrule when compared to the other models (without ferrule 0.0696, short ferrule 0.0492, cylindrical fer-rule 0.0248, and beveled ferrule 0.0387 MPa.Conclusion: Endodontically treated maxillary central incisors with a ferrule length vary-ing between 0.5 mm and 2.0 mm exhibit lower stress distribution compared to those with-out a ferrule. Keeping a long ferrule is suggested to decrease the stress at the cervical area of restored teeth.

  5. A case of solitary median maxillary central incisor (SMMCI) syndrome with bilateral pyriform aperture stenosis and choanal atresia.

    Science.gov (United States)

    Blackmore, Kate; Wynne, David M

    2010-08-01

    Solitary median maxillary central incisor syndrome is a rare disorder involving midline abnormalities. It may present with life threatening respiratory distress in the neonate secondary to nasal malformations. These include pyriform aperture stenosis and choanal atresia. We present the first reported case of simultaneous choanal atresia and pyriform aperture stenosis in a neonate with solitary median maxillary central incisor syndrome. The clinical presentation and the management of congenital pyriform aperture stenosis are discussed. PMID:20627328

  6. Morphometric analysis of pulp size in maxillary permanent central incisors correlated with age: An indirect digital study

    Science.gov (United States)

    Ravindra, S. V.; Mamatha, G. P.; Sunita, J. D.; Balappanavar, Aswini Y.; Sardana, Varun

    2015-01-01

    Context: Teeth are hardest part of the body and are least affected by the taphonomic process. They are considered as one of the reliable methods of identification of a person in forensic sciences. Aim: The aim of the following study is to establish morphometeric measurements by AutoCad 2009 (Autodesk, Inc) of permanent maxillary central incisors in different age groups of Udaipur population. Setting and Design: Hospital-based descriptive cross-sectional study carried out in Udaipur. Materials and Methods: A study was carried out on 308 subjects of both genders with the age range of 9-68 years. Standardized intra-oral radiographs were made by paralleling technique and processed. The radiographs were scanned and the obtained images were standardized to the actual size of radiographic film. This was followed by measuring them using software AutoCad 2009. Statistical Analysis Used: F-test, post-hoc test, Pearson's correlation test. Results: For left maxillary central incisor, the total pulp area was found to be of 38.41 ± 12.88 mm and 14.32 ± 7.04 mm respectively. For right maxillary central incisor, the total pulp size was 38.39 ± 14.95 mm and 12.35 ± 5 mm respectively. Males (32.50, 32.87 mm2) had more pulp area when compared with females (28.82, 30.05 mm2). Conclusion: There was a decrease in total pulp area with increasing age which may be attributed to secondary dentin formation. PMID:26816461

  7. The non-vital discolored central incisor dilemma.

    Science.gov (United States)

    Schlichting, Luís Henrique; Stanley, Kyle; Magne, Michel; Magne, Pascal

    2015-01-01

    The restoration of anterior teeth is frequently a demanding mission. Patients generally have high expectations for the anterior region, which makes the emotional side of treatment especially important. When this involves discolored endodontically treated teeth, consensus can hardly ever be found as to the chosen approach. Bleaching with direct composites is undoubtedly the most conservative choice for these cases. However, this may require more maintenance (touch-up bleaching and repairs) in the long term, which is an important issue for adult patients. On the other hand, bonded porcelain veneers represent a more 'high-end' option, as they recover the original biomechanics of the intact tooth, allow an optimal masking of the substrate, remain stable, and have a reasonable biological cost when compared to full-coverage crowns. This strategy is explained in this article and documented with a clinical case. We describe treatment planning based on the biomimetic concept, taking into consideration what is possible with current materials and techniques when combined with the patient's particular needs, including the introduction of an innovative step during dentin sealing--the microsuction. The laboratory work was totally accomplished by 'teledentistry', with no direct contact between the dental technologist and the patient. PMID:26794051

  8. Solitary median maxillary central incisor syndrome: clinical case with a novel mutation of sonic hedgehog.

    Science.gov (United States)

    Garavelli, Livia; Zanacca, C; Caselli, G; Banchini, G; Dubourg, C; David, V; Odent, S; Gurrieri, F; Neri, G

    2004-05-15

    Solitary median maxillary central incisor (SMMCI) is a rare dental anomaly. It is usually considered as a minor manifestation of holoprosencephaly (HPE). Some reported families had severe cases of HPE in some members and SMMCI in others. Mutations of Sonic Hedgehog (SHH) have been documented in these families. SMMCI has also been found as an isolated finding or together with other anomalies such as microcephaly, short stature, endocrine pathology, and choanal atresia. We describe a patient with SMMCI and a novel SHH mutation: Val332Ala. PMID:15103725

  9. Compound odontoma associated with an unerupted rotated and dilacerated maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Vinaya Kumar Kulkarni

    2011-01-01

    Full Text Available Odontomas are benign tumors containing various component tissues of teeth. They usually remain asymptomatic and are diagnosed on routine radiographs. Clinically, they are often associated with delayed eruption or impaction of permanent teeth and retained primary teeth. A case of compound odontoma in association with an unerupted, rotated and dilacerated maxillary permanent right central incisor in a 12-year-old boy is reported. Such combination is rare, making it an interesting case for reporting. We have also discussed the clinical features, diagnosis and treatment of such a condition.

  10. Finite elements study of the Flexi Post and Flexi Flange post systems in a maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Lewgoy Hugo Roberto

    2003-01-01

    Full Text Available The use of post and core systems has become an excellent alternative for restoring endodontically treated teeth. The aim of this study was to evaluate the von Mises, maximal compressive and tensile stresses distribution using the Finite Element Method (FEM on human teeth restored with different post and core systems. The analysis was made on endodontically treated maxillary central incisors. The post systems used in this investigation were the stainless steel or titanium Flexi Post/Flexi Flange. Composite resin was used as core material and resin cement was the cement material of choice to seat a full porcelain crown. The bi-dimensional mathematical model was created from pictures taken from an intact human maxillary central incisor and prefabricated posts. This image was transferred to a personal computer in the MSC/Nastran 4.5 software. A static and linear analysis treatment was performed when a 45º load of 100 N was applied on the lingual surface of the tooth. Based on the results obtained, it can be concluded that the post design and its material can alter the stress pattern distribution.

  11. Finite elements study of the Flexi Post and Flexi Flange post systems in a maxillary central incisor.

    Science.gov (United States)

    Lewgoy, Hugo Roberto; Youssef, Michel Nicolau; Matson, Maurício Rufaiel; Bocangel, Jorge Antônio Javier Saldivar; Netto, Camillo Anauate; Amore, Ricardo

    2003-01-01

    The use of post and core systems has become an excellent alternative for restoring endodontically treated teeth. The aim of this study was to evaluate the von Mises, maximal compressive and tensile stresses distribution using the Finite Element Method (FEM) on human teeth restored with different post and core systems. The analysis was made on endodontically treated maxillary central incisors. The post systems used in this investigation were the stainless steel or titanium Flexi Post/Flexi Flange. Composite resin was used as core material and resin cement was the cement material of choice to seat a full porcelain crown. The bi-dimensional mathematical model was created from pictures taken from an intact human maxillary central incisor and prefabricated posts. This image was transferred to a personal computer in the MSC/Nastran 4.5 software. A static and linear analysis treatment was performed when a 45 load of 100 N was applied on the lingual surface of the tooth. Based on the results obtained, it can be concluded that the post design and its material can alter the stress pattern distribution. PMID:14569354

  12. Temporary management of permanent central incisors loss caused by trauma in primary dentition with natural crowns: a case report.

    Science.gov (United States)

    Tüzüner, Tamer; Kuşgöz, Adem; Nur, Bilge Gülsüm

    2009-10-01

    Primary teeth injuries may cause developmental disturbances in the permanent dentition and loss of permanent incisors could be treated with different options. In this case report, an 11-year-old boy, with a history of trauma at the age of 4 years, is presented. Premature loss of permanent upper right central and upper left central teeth because of the mobility and arrest in root development were treated using patient's own natural crowns on a removable appliance. This treatment option could be considered as an esthetic and functional temporary management of permanent central incisors loss until the definitive treatment will be completed in the future.

  13. Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst.

    Science.gov (United States)

    Kalaskar, Ritesh R; Kalaskar, Ashita R

    2011-01-01

    Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens) is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning. PMID:22114457

  14. Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst

    Directory of Open Access Journals (Sweden)

    Ritesh R Kalaskar

    2011-01-01

    Full Text Available Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning.

  15. Strain Distribution in Root Surface Dentin of Maxillary Central Incisors during Lateral Compaction

    Science.gov (United States)

    Pilo, Raphael; Metzger, Zvi; Brosh, Tamar

    2016-01-01

    Aim To precisely quantify the circumferential strains created along the radicular dentin of maxillary incisors during a simulated clinical procedure of lateral compaction. Methods Six miniature strain gauges were bonded on the roots of fourteen recently extracted maxillary central incisors that were subjected to root canal instrumentation. The strain gauges were bonded at three levels (apical, middle, and coronal) and four aspects (buccal, lingual, mesial, and distal) of the roots. Each tooth was embedded in a PVC cylinder containing polyvinyl-siloxane impression material. Root filling was then performed by simulating the clinical procedure of lateral compaction using nickel-titanium finger spreaders. The force applied to the spreader and the strains developing in the surface root dentin were continuously recorded at a frequency of 10 Hz. Results The highest strains that developed during lateral compaction were in the mesial and distal aspects at the apical level of the root. The magnitudes of the maximal mesial/distal strains at the apical as well as the mid-root levels were approximately 2.5–3 times higher than those at the buccal/lingual aspects (p = 0.041). The strains decreased significantly (pdentin but decrease gradually to negligible levels. PMID:27227404

  16. 上颌埋伏阻生中切牙的影像学分类%Imaging classification of maxillary impacted central incisors

    Institute of Scientific and Technical Information of China (English)

    王镶珊; 胡荣党

    2012-01-01

    PURPOSE: To investigate the classification of maxillary impacted central incisors through three-dimensional images. METHODS: Based on the original Dicom data of the spiral computed tomography of 103 patients with maxillary impacted central incisors, the three-dimensional images of maxillary impacted central incisors were reconstructed by Mimics 10.0 software, and the characteristics were analyzed and a classification was proposed. RESULTS: There were 106 teeth included in this study, 74 teeth were located labially, including 33 inverted impacted teeth, 28 horizontally impacted teeth, and 13 inclined teeth. 20 teeth were located in the palatal side, including 11 inclined teeth and 9 horizontally impacted teeth. 12 teeth were within the bone, which can be divided into three categories based on the position of the crown and in accordance with the vertical, liar to near, and horizontal direction. Type I was labially impacted incisor, including 3 subdivisions: labially inclined impacted, labially horizontal impacted and labially inverted i mpacted. Type II was palatally impacted incisor, including 2 subdivisions: palatally inclined impacted and palatally horizontal impacted. Type 111 was vertically impacted incisor. CONCLUSIONS: The maxillary impacted incisors can be divided into 3 categories based on three-dimensional directions, and subdivisions can be created in each group including labially (inclined, horizontal, inverted) impacted incisors, palatally (inclined, horizontal) impacted incisor and vertically impacted incisors.%目的:探讨上颌埋伏阻生中切牙的三维图像分类特征.方法:根据103例上颌中切牙埋伏阻生患者螺旋CT的Dicom原始数据,应用Mimics10.0软件重建出上颌埋伏阻生中切牙的三维图像,分析上颌埋伏阻生中切牙的阻生特点,并对其进行分类.结果:共有埋伏牙106颗.74颗牙为唇侧阻生,倒置阻生33颗,水平阻生28颗,倾斜阻生13颗;20颗为腭侧阻生,倾斜阻生11

  17. Multidisciplinary management of subgingival crown-root fracture of an immature permanent maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Samir Zahedpasha

    2012-01-01

    Full Text Available This case report describes the multidisciplinary management of subgingival horizontal crown-root fracture of an immature permanent maxillary central incisor in a 10-year-old boy. After removal of the fractured fragment, pulpotomy was performed within 48 h from the injury to promote apexogenesis. The tooth was orthodontically extruded until the fracture line was located above the alveolar bone level. Frenectomy, supracrestal fiberotomy, and crown lengthening were performed after adequate stabilization of the extruded tooth for 5 months. Finally, the tooth was restored with composite resin by using the acid etch technique. This report highlights that a multidisciplinary treatment approach with strict cooperation among specialists to manage a complicated crown-root fracture can save and restore a traumatized immature permanent tooth.

  18. Maturogenesis of Two Maxillary Central Incisors: A Case Report with 10 Years of Follow Up

    Directory of Open Access Journals (Sweden)

    Abdollah Ghorbanzadeh

    2015-10-01

    Full Text Available This case report describes the treatment of two immature maxillary central incisors in a 7- year-old female patient. She suffered complicated crown fracture because of trauma, and the root formation was incomplete. White mineral trioxide aggregate (MTA was selected as the pulp-capping material after cervical pulpotomy to preserve the pulp tissue vitality and achieve maturogenesis. Follow-up evaluations showed successful treatment in terms of preservation of pulp vitality and demonstrated marked continuous physiological root devel- opment. During 10 years of follow-up, both teeth were clinically asymptomatic, and radio- graphic evaluations showed apparent root regeneration with apical root-end closure without pulp or periapical pathosis.

  19. A Case Report of Compound Odontoma Associated with an Unerupted Maxillary Central Incisor

    Directory of Open Access Journals (Sweden)

    Eda Arat Maden

    2014-02-01

    Full Text Available Odontomas generally appear as small, solitary or multiple radio-opaque lesions found on routine radiographic examinations. Traditionally, odontomas are the most common type of odontogenic tumor and they are generally asymptomatic. Occasionally, odontomas may cause disturbances in the eruption of teeth, such as impaction, delay eruption or retention of primary teeth. In general, odontomas occur more often in the permanent dentition. This is a case report of a compound composite odontoma in an 8-year-old boy, which has resulted in failure of eruption of the permanent upper right central incisor while the contra-lateral tooth had erupted. [Arch Clin Exp Surg 2014; 3(1.000: 47-51

  20. Replacement of mandibular central incisors with implant-supported crowns: a case report.

    Science.gov (United States)

    Bäumer, Daniel; Zuhr, Otto; Hürzeler, Markus

    2016-01-01

    Anterior teeth are often affected by accidental dental trauma and may eventually be lost. When the neighboring teeth are unharmed, implant-supported crowns are often the preferred treatment choice. When not only the teeth but also the supporting hard and soft tissue has been lost, surgical reconstruction may be needed. However, in combined horizontal and vertical class III defects, the available augmentation techniques are often not predictable. In this case report, two neighboring mandibular central incisors were replaced by two implants after soft and hard tissue augmentation with the cortical bone plate method. The interdental soft tissue was reconstructed with remarkable success, making this an example of what can be achieved in cases such as this. PMID:27092347

  1. Radiographic and clinical aspects of endodonty of the central incisor, in maxilla: a case report

    International Nuclear Information System (INIS)

    The authors in the current report introduce a study of the present features when of agenesis of dental elements on the maxilla-mandibular complex. They relate a case of right upper central incisor's hypodontia, describing its clinical and radiographic appearances. Through a large revision of literature about this field, they found out that a disappearance of this element on the human dentition is rare, associating for this: genetic, familiar, nutrient, hormonal, infections and traumatic agents. Finally, they alert for the fact that an accurate clinical examination, complemented by a exact radiographic survey, will make possible a precocious diagnosis and execution of more efficient therapeutic manipulations that reduce the problems of functional, esthetic and phonetics order. (author)

  2. Biologic restoration of a traumatized maxillary central incisor in a toddler: A case report

    Directory of Open Access Journals (Sweden)

    Sheen Ann John

    2014-01-01

    Full Text Available Trauma to the anterior teeth is relatively common in young children and teenagers. Traumatized anterior teeth require quick functional and aesthetic repair, and poses a challenge to the dental practitioner owing to the lack of co-operation ceded and the longer time invested. Reattachment of tooth fragment should be the first choice to restoring teeth when a usable fragment is available, since it gives a psychological and aesthetic advantage over the conventional technique. With the vast improvement in adhesive technology, reattachment is definitely a predictable treatment option for very young children. This paper describes the treatment of a 2½ year old female child who sustained crown-root fracture, extending subgingivally, in primary upper central incisor.

  3. A CAD-CAM prosthodontic option and gingival zenith position for a rotated maxillary right central incisor: An evaluation

    Directory of Open Access Journals (Sweden)

    Mukesh Singhal

    2012-01-01

    Conclusion: Digital imaging provides an immediate treatment option for the patients. Software also provides an interim aid, for the clinician as well as technician, in the form of two-dimensional photographs. CAD-CAM is entirely a helping instrument against the conservative prosthetic options and gingival zenith position for a rotated central incisor. It helps in patient education and in motivation.

  4. [Differences between laypersons and orthodontists in recognizing the light reflection zone on the maxillary central incisors crowns].

    Science.gov (United States)

    Shmuli, T; Wasserstein, A; Turgeman, R; Brezniak, N

    2014-07-01

    The light reflection zone (LRZ) is a new parameter that may serve as a tool for the diagnosis of smile esthetics. It is a bright white dot or area that appears on the surface of the maxillary central incisors and/or the gingiva of the front teeth, visible in intra-oral and smile extra-oral photographs. Recently it was found that the general population defines a nicer smile when the LRZ is located in the gingival area of the upper central incisors' surface rather than the incisal third. The aim of this study was to find out in two populations that are not aware of this new parameter, laypersons and orthodontists, whether there is a difference in the identification of the LRZ and the importance of the LRZ in determining the quality of the smile. Twelve pairs of facial photographs, including 10 of ordinary smiling persons and 2 of smiling models, were presented to 108 laypersons and 30 orthodontists. The only difference between each pair was the location of the LRZ that was moved, compared to the original photograph, gingivally or incisally respectively, using Photoshop (Adobe). Each participant was asked to mark whether he/she noticed a difference between the 2 pictures, and if so, to score the nicer smile. Data analysis was carried out using Chi square test and Fisher's exact test (SPSS v17). The results showed that both populations had difficulty in recognizing the differences between the pictures that were based solely on the LRZ parameter. However, when differences were recognized, most of the participants in both populations pointed on the smile where the LRZ was located gingivally as the nicer one. The orthodontic population recognized the difference between the two pictures, in which only the LRZ was changed, to a lesser extent compared to the laypersons populations. This result was with statistical significance (p = 0.007). PMID:25219098

  5. Orthodontic correction of severely rotated maxillary central incisor in a diabetic adult

    Directory of Open Access Journals (Sweden)

    Rajesh Gyawali

    2015-12-01

    Full Text Available Background: Orthodontics has recently seen an increase in the number of adult population seeking treatment. Financial dependency, increasing awareness and availability of service can be the reasons behind this rise. Though, clinical myths regarding duration, effectiveness of treatment, associated systemic conditions still exist, these should be of no concern and with adequate monitoring and procedural modifications, conventional orthodontic treatment is possible.Case description: A 58 year old Type II diabetic male presented to orthodontic clinic with unesthetic gap between upper front teeth. The history revealed extraction of painful mesiodens. On examination, the patient had Class I molar, canine and incisor relationship. 21 was rotated with 5mm of space between central incisors. Fixed orthodontic treatment was planned after physician consultation regarding his diabetic condition. Bondable buccal tubes instead of bands were used in first molars, 0.022” Roth brackets were bonded on other maxillary teeth. The wire gradually progressed from 0.014”NiTi, 0.016”NiTi to 0.018”SS. Lingual button was attached on the labial and lingual surface of 21 to apply couple. After the correction of rotation of 21, remaining space closure with esthetic contouring of 21 was done. Maintenance of adequate oral hygiene was reinforced throughout the treatment period. Fixed lingual retainer was bonded and pericision performed to retain the achieved result.Conclusion: Orthodontic treatment can be carried out in diabetic adults with good glycemic control to achieve esthetic results; however, measures for maintenance of adequate oral hygiene should be undertaken. Interdisciplinary approach involving restorative procedures can enhance the esthetics achieved.JCMS Nepal. 2015;11(3:30-34

  6. Surgical management of multiple supernumerary teeth and an impacted maxillary permanent central incisor.

    Science.gov (United States)

    Rallan, Mandeep; Rallan, Neelakshi Singh; Goswami, Mousumi; Rawat, Kamini

    2013-01-01

    Hyperdontia is the condition of having supernumerary teeth, or teeth which appear in addition to the regular number of teeth. It is a developmental anomaly and has been argued to arise from multiple aetiologies. The most common site is the maxillary incisor region; but the prevalence of more than three teeth supernumerary tooth is less than 1%. A case of 13 year male patient is reported with a multiple impacted supernumerary tooth in maxillary anterior region hindering the eruption of right permanent central incisor. The supernumerary tooth was treated via surgical approach followed by an interim prosthesis for permanent central incisor which later on erupted in due course of time. Background Supernumerary teeth may be defined as any teeth or tooth substance in excess of the usual configuration of 20 deciduous and 32 permanent teeth. The presence of supernumerary teeth in the premaxillary region often poses unique diagnostic and managerial concerns for the practitioner. Rarely is the surplus number compensated by an absence or deficiency of other teeth. Therefore, the dysfunctional nature of supernumerary teeth and their ability to create a variety of pathological disturbances in the normal eruption and position of adjacent teeth warrants their early detection and prudent management. Approximately 76-86% of cases represent single-tooth hyperdontia, with two supernumerary teeth noted in 12-23% and three or more extra teeth noted in less than 1% of cases. Multiple supernumerary teeth are also associated with many syndromes like cleidocranial dysplasia and Gardner’s syndrome etc. However, it is rare to find multiple supernumeraries in individuals with no other associated disease or syndrome. In such cases, the maxillary anterior region is the common site of occurrence. The exact aetiology is not clearly understood. The supernumerary teeth result from any disturbance in the initiation and proliferation stages of odontogenesis. There are several theories regarding the

  7. Stress distributions in maxillary central incisors restored with various types of post materials and designs.

    Science.gov (United States)

    Madfa, A A; Kadir, M R Abdul; Kashani, J; Saidin, S; Sulaiman, E; Marhazlinda, J; Rahbari, R; Abdullah, B J J; Abdullah, H; Abu Kasim, N H

    2014-07-01

    Different dental post designs and materials affect the stability of restoration of a tooth. This study aimed to analyse and compare the stability of two shapes of dental posts (parallel-sided and tapered) made of five different materials (titanium, zirconia, carbon fibre and glass fibre) by investigating their stress transfer through the finite element (FE) method. Ten three-dimensional (3D) FE models of a maxillary central incisor restored with two different designs and five different materials were constructed. An oblique loading of 100 N was applied to each 3D model. Analyses along the centre of the post, the crown-cement/core and the post-cement/dentine interfaces were computed, and the means were calculated. One-way ANOVAs followed by post hoc tests were used to evaluate the effectiveness of the post materials and designs (p=0.05). For post designs, the tapered posts introduced significantly higher stress compared with the parallel-sided post (pmaterials, the highest level of stress was found for stainless steel, followed by zirconia, titanium, glass fibre and carbon fibre posts (p<0.05). The carbon and glass fibre posts reduced the stress distribution at the middle and apical part of the posts compared with the stainless steel, zirconia and titanium posts. The opposite results were observed at the crown-cement/core interface.

  8. Strain Distribution in Root Surface Dentin of Maxillary Central Incisors during Lateral Compaction.

    Directory of Open Access Journals (Sweden)

    Raphael Pilo

    Full Text Available To precisely quantify the circumferential strains created along the radicular dentin of maxillary incisors during a simulated clinical procedure of lateral compaction.Six miniature strain gauges were bonded on the roots of fourteen recently extracted maxillary central incisors that were subjected to root canal instrumentation. The strain gauges were bonded at three levels (apical, middle, and coronal and four aspects (buccal, lingual, mesial, and distal of the roots. Each tooth was embedded in a PVC cylinder containing polyvinyl-siloxane impression material. Root filling was then performed by simulating the clinical procedure of lateral compaction using nickel-titanium finger spreaders. The force applied to the spreader and the strains developing in the surface root dentin were continuously recorded at a frequency of 10 Hz.The highest strains that developed during lateral compaction were in the mesial and distal aspects at the apical level of the root. The magnitudes of the maximal mesial/distal strains at the apical as well as the mid-root levels were approximately 2.5-3 times higher than those at the buccal/lingual aspects (p = 0.041. The strains decreased significantly (p<0.04 from the apical through the mid-root levels to the coronal level, yielding gradients of 2.5- and 6-fold, respectively. The mesial and distal strains were consistently tensile and did not differ significantly; however, the buccal strains were generally 35-65% higher than the lingual strains (p = 0.078. Lateral compaction resulted in the gradual build-up of residual strains, resulting in generation of a 'stair-step' curve. These strains declined gradually and almost completely disappeared after 1000 sec.With proper mounting of several miniature strain gauges at various levels and aspects of the root, significant circumferential strains can be monitored under clinically relevant compaction forces. The residual strains at the end of lateral compaction are not stored in the

  9. Management of Traumatic Injury to Maxillary Central Incisors associated with Inverted Mesiodens: A Case Report

    OpenAIRE

    Pavuluri, Chaitanya; Nuvvula, Sivakumar

    2013-01-01

    ABSTRACT Maxillary incisors are the most frequently injured teeth in the primary and permanent dentition. Stage of adolescence show a significant number of dental injuries as they engage in contact sports. Children with accident prone profile, i.e. class II division I or class I type II malocclusion are more prone for injuries because of the proclined maxillary incisors. Supernumerary teeth are those that are additional to the normal complement. They occur in single or multiple, unilateral or...

  10. Non-surgical management of a mutilated maxillary central incisor with open apex and large periapical lesion

    OpenAIRE

    Puneet Ajwani; Nalini Saini

    2011-01-01

    A 24-year-old female patient reported with a mutilated maxillary left central incisor. The coronal tooth structure remaining was very less, discolored, and brittle. She gave history of trauma about 15 years back when the tooth got fractured. An intraoral periapical radiograph revealed an open apex and a large periapical lesion. The case was managed successfully by conservative means using intracanal calcium hydroxide and mineral trioxide aggregate (MTA) apical barrier followed by a fiber post...

  11. Finite elements study of the Flexi Post and Flexi Flange post systems in a maxillary central incisor

    OpenAIRE

    Lewgoy Hugo Roberto; Youssef Michel Nicolau; Matson Maurício Rufaiel; Bocangel Jorge Antônio Javier Saldivar; Anauate Netto Camillo; Amore Ricardo

    2003-01-01

    The use of post and core systems has become an excellent alternative for restoring endodontically treated teeth. The aim of this study was to evaluate the von Mises, maximal compressive and tensile stresses distribution using the Finite Element Method (FEM) on human teeth restored with different post and core systems. The analysis was made on endodontically treated maxillary central incisors. The post systems used in this investigation were the stainless steel or titanium Flexi Post/Flexi Fla...

  12. Accelerated Osteogenic Orthodontics™ for retreatment of a patient with diminished root length and absence of the maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Armando Montesinos F

    2015-10-01

    Full Text Available An 18-year-old female patient visited a university orthodontics department with a chief complaint of an unesthetic appearance of her teeth, including a protruded upper central incisor and unsatisfactory results from previous orthodontic treatment. Pretreatment records showed a Class II skeletal and dental relation with proclined upper and lower incisors, replacement of an absent upper left central incisor with the left upper cuspid, presence of the upper left deciduous cuspid, mild crowding, and 4 mm of overbite and overjet. The panoramic radiograph showed shortened roots of multiple teeth. Accelerated Osteogenic Orthodontics™ (AOO™ was recommended as an approach to reduce the treatment time and the risk of further root shortening. Despite being more expensive and requiring a surgical procedure, this treatment option was very attractive to the patient. The overall treatment time was 14 months. Facial balance was improved, and good occlusal relationships were achieved from the functional and esthetic perspectives. In conclusion, surgically facilitated orthodontics (specifically, AOO™ is an efficient and safe therapeutic tool for treating or retreating orthodontic patients with diminished root length.

  13. Accelerated Osteogenic Orthodontics™ for retreatment of a patient with diminished root length and absence of the maxillary central incisor.

    Science.gov (United States)

    Montesinos F, Armando; Linares T, Silvana; Pérez-Gasque B, Marisol

    2015-10-01

    An 18-year-old female patient visited a university orthodontics department with a chief complaint of an unesthetic appearance of her teeth, including a protruded upper central incisor and unsatisfactory results from previous orthodontic treatment. Pretreatment records showed a Class II skeletal and dental relation with proclined upper and lower incisors, replacement of an absent upper left central incisor with the left upper cuspid, presence of the upper left deciduous cuspid, mild crowding, and 4 mm of overbite and overjet. The panoramic radiograph showed shortened roots of multiple teeth. Accelerated Osteogenic Orthodontics™ (AOO™) was recommended as an approach to reduce the treatment time and the risk of further root shortening. Despite being more expensive and requiring a surgical procedure, this treatment option was very attractive to the patient. The overall treatment time was 14 months. Facial balance was improved, and good occlusal relationships were achieved from the functional and esthetic perspectives. In conclusion, surgically facilitated orthodontics (specifically, AOO™) is an efficient and safe therapeutic tool for treating or retreating orthodontic patients with diminished root length. PMID:26644760

  14. 3D FEA of cemented glass fiber and cast posts with various dental cements in a maxillary central incisor

    OpenAIRE

    Ahmed A. Madfa; Al-Hamzi, Mohsen A.; Al-Sanabani, Fadhel A.; Al-Qudaimi, Nasr H.; Yue, Xiao-Guang

    2015-01-01

    This study aimed to analyse and compare the stability of two dental posts cemented with four different luting agents by examining their shear stress transfer through the FEM. Eight three-dimensional finite element models of a maxillary central incisor restored with glass fiber and Ni–Cr alloy cast dental posts. Each dental post was luted with zinc phosphate, Panavia resin, super bond C&B resin and glass ionomer materials. Finite element models were constructed and oblique loading of 100 N was...

  15. SHH mutation is associated with solitary median maxillary central incisor: a study of 13 patients and review of the literature.

    Science.gov (United States)

    Nanni, L; Ming, J E; Du, Y; Hall, R K; Aldred, M; Bankier, A; Muenke, M

    2001-07-22

    Solitary median maxillary central incisor (SMMCI) or single central incisor is a rare dental anomaly. It has been reported in holoprosencephaly (HPE) cases with severe facial anomalies or as a microform in autosomal dominant HPE (ADHPE). In our review of the literature, we note that SMMCI may also occur as an isolated finding or in association with other systemic abnormalities. These anomalies include short stature, pituitary insufficiency, microcephaly, choanal atresia, midnasal stenosis, and congenital nasal pyriform aperture stenosis. SMMCI can also be a feature of recognized syndromes or associations or a finding in patients with specific chromosomal abnormalities. We performed a molecular study on a cohort of 13 SMMCI patients who did not have HPE. We studied two genes, Sonic Hedgehog (SHH) and SIX3, in which mutations have been reported in patients showing SMMCI as part of the HPE spectrum. A new missense mutation in SHH (I111F), segregating in one SMMCI family, was identified. Our results suggest that this mutation may be specific for the SMMCI phenotype since it has not been found in the HPE population or in normal controls. Published 2001 Wiley-Liss, Inc. PMID:11471164

  16. A Fused Maxillary Central Incisor and Its Multidisciplinary Treatment: An 18-Year Follow-Up

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    Lluís Brunet-Llobet

    2014-01-01

    Full Text Available Fused teeth may cause aesthetic, spacing, periodontal, eruption, and caries problems. The present case report describes a 7-year-old boy patient with a chief complaint of unerupted maxillary incisor. Radiographic examination indicated a fused tooth which had two fused roots but two independent root canals. A complex management of a fused tooth is really difficult to standardize. In this case an orthodontic, endodontic, and surgical treatment (intentional replantation allowed the tooth to be retained until 18 years following intervention. Maintenance of the root and alveolar bone in young adults at least until full skeletal maturation should be the main treatment objective.

  17. Compound odontoma associated with an unerupted and dilacerated maxillary primary central incisor in a young patient.

    Science.gov (United States)

    Yeung, K H; Cheung, R C T; Tsang, M M H

    2003-05-01

    The occurrence of odontoma in the primary dentition is uncommon. There are very few reports of non-eruption of a dilacerated primary tooth in the literature. A rare case of compound odontoma in association with an unerupted dilacerated maxillary primary incisor in a young patient is reported. There was also a developing supernumerary tooth in the vicinity of the odontoma. The clinical features and management of these conditions are discussed. The relevant literature is reviewed. A possible causal relationship between odontoma and dilaceration is highlighted.

  18. Compound odontoma associated with impacted maxillary central incisor dictates a need to be vigilant to canine eruption pattern: A 2-year follow-up.

    Science.gov (United States)

    Singla, Shilpy; Gupta, Sachin

    2016-01-01

    Canine deviation from its path of eruption is usually followed by either delayed or impaction of canine. One of the important and not so noticed reasons for canine displacement is formerly impacted central incisor. The difference in age of eruption of these two teeth is 4 years; however, the absence of maxillary incisor should be perceived with utmost conviction about impending canine displacement leading to its impaction as well. This case presents similar picture where composite, compound odontoma with respect to maxillary central incisor led to its impaction resulted in deviated path of eruption for erupting canine. This canine displacement to worsen prognosis ended up getting impacted if not dealt with cautiously in the later stages of occlusal development.

  19. Síndrome do incisivo central superior solitário: relato de caso Solitary median maxillary central incisor syndrome: case report

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    Eduardo Machado

    2010-08-01

    Full Text Available INTRODUÇÃO: a presença de um incisivo central superior solitário é um evento bastante incomum na população. A prevalência da chamada Síndrome do Incisivo Central Superior Solitário (SICSS é verificada em 1:50.000 nascimentos, sendo registrado um maior acometimento no sexo feminino. Essa alteração no desenvolvimento da oclusão dentária é caracterizada por más formações estruturais, sobretudo na região de linha média do paciente. O diagnóstico precoce e o tratamento adequado dessa síndrome são de grande importância, pois essa condição talvez seja um indicativo de que o paciente pode apresentar outras más formações congênitas severas, não devendo ser a SICSS considerada uma simples anomalia dentária. Os procedimentos ortodônticos, nesses casos, variam dependendo do grau de comprometimento das estruturas ósseas da maxila, da oclusão em si, e principalmente da sutura palatina mediana. OBJETIVO: discutir, baseado em evidências científicas, aspectos importantes relacionados à SICSS, bem como apresentar um caso clínico de paciente do sexo feminino com SICSS, que foi submetida a tratamento ortodôntico na Clínica Odontológica Integrada Infantil da Universidade Federal de Santa Maria / RS. CONCLUSÃO: pela análise crítica da literatura, verifica-se ser muito importante o diagnóstico correto e precoce acerca dessa síndrome, visto que há possibilidade da mesma estar associada a outros problemas de desenvolvimento. Além disso, o paciente acometido pela SICSS deve ser assistido por uma equipe multidisciplinar de saúde, de forma a otimizar os resultados clínicos e devolver-lhe qualidade de vida.INTRODUCTION: The presence of a single median maxillary central incisor is an uncommon event in the population. The prevalence of the Solitary Median Maxillary Central Incisor (SMMCI syndrome is about 1:50,000 live births, occurring more in women. This alteration in the development of the dental occlusion is

  20. A rare case of dilated invaginated odontome with talon cusp in a permanent maxillary central incisor diagnosed by cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Jaya, Ranganathan; Kumar, Rangarajan Sundaresan Mohan; Srinivasan, Ramasamy [Dept. of Conservative Dentistry and Endodontics, Priyadarshini Dental College and Hospital, Chennai (India)

    2013-09-15

    It has been a challenge to establish the accurate diagnosis of developmental tooth anomalies based on periapical radiographs. Recently, three-dimensional imaging by cone beam computed tomography has provided useful information to investigate the complex anatomy of and establish the proper management for tooth anomalies. The most severe variant of dens invaginatus, known as dilated odontome, is a rare occurrence, and the cone beam computed tomographic findings of this anomaly have never been reported for an erupted permanent maxillary central incisor. The occurrence of talon cusp occurring along with dens invaginatus is also unusual. The aim of this report was to show the importance of cone beam computed tomography in contributing to the accurate diagnosis and evaluation of the complex anatomy of this rare anomaly.

  1. A rare case of dilated invaginated odontome with talon cusp in a permanent maxillary central incisor diagnosed by cone beam computed tomography

    International Nuclear Information System (INIS)

    It has been a challenge to establish the accurate diagnosis of developmental tooth anomalies based on periapical radiographs. Recently, three-dimensional imaging by cone beam computed tomography has provided useful information to investigate the complex anatomy of and establish the proper management for tooth anomalies. The most severe variant of dens invaginatus, known as dilated odontome, is a rare occurrence, and the cone beam computed tomographic findings of this anomaly have never been reported for an erupted permanent maxillary central incisor. The occurrence of talon cusp occurring along with dens invaginatus is also unusual. The aim of this report was to show the importance of cone beam computed tomography in contributing to the accurate diagnosis and evaluation of the complex anatomy of this rare anomaly.

  2. An analysis of reliability and validity of the papilla index score of implant-supported single crowns of maxillary central incisors

    DEFF Research Database (Denmark)

    Peng, Min; Fei, Wei; Hosseini, Mandana;

    2012-01-01

    Objectives: To test the reliability and validity of the papilla index scores of the implant-supported single crowns (ISSCs) of maxillary central incisors. Materials and Methods: Twenty-five patients with 25 ISSCs were included. Two prosthodontists evaluated the papilla index score (PIS) of three ...

  3. Influence of implant position on clinical crown length and peri-implant soft tissue dimensions at implant-supported single crowns replacing maxillary central incisors

    DEFF Research Database (Denmark)

    Peng, Min; Fei, Wei; Hosseini, Mandana;

    2013-01-01

    The aims of the present study were to evaluate the influence of implant position on clinical crown length and marginal soft tissue dimensions at implant-supported single crowns of maxillary central incisors, and to validate the papilla index score (PIS). Twenty-five patients, who had lost one...

  4. Finite element analysis of periodontal tissue stress distribution of labial inverted impacted maxillary central incisor%上颌唇向倒置埋伏中切牙牙周应力分布的有限元研究

    Institute of Scientific and Technical Information of China (English)

    回记芳; 张晗; 曲晓东; 闫伟军; 邵玶

    2015-01-01

    目的:建立上颌唇向倒置埋伏中切牙及其支持组织的三维模型,分析其在不同工况下的牙周应力分布,为治疗上颌埋伏中切牙提供参考。方法利用锥形束CT(CBCT)原始数据,结合Mimics 10.01和Ansys 14.0软件建立上颌唇向倒置埋伏中切牙及其牙周组织的有限元模型。在埋伏牙切端沿其长轴垂直方向,分别加载20、30、40、50、60、70 g集中力,并测定不同工况下牙周膜Von Mises应力分布。结果牙周膜应力随牵引力的增加而增大,30 g力时最大Von Mises应力值为24919.0 Pa,在牙周膜的最适应力范围内且接近其最大值。结论矫治初期,上颌唇向倒置埋伏中切牙的适宜牵引力较小,约为30 g。%Objective This study aims to do the following: construct a three-dimensional finite element model of an labial inverted impacted maxillary central incisor and its supporting tissues, analyze stress distribution in the periodontal tissue when various tractions are exerted, and provide references for treating impacted maxillary central incisor. Methods A three-dimensional finite element model of labial inverted impacted maxillary central incisor and its periodontal tissues was established using Mimics 10.01 and Ansys 14.0 software based on original cone beam computed tomography (CBCT) data. Various traction values (20, 30, 40, 50, 60, and 70 g) were exerted on the incisal margin in the direction perpendicular to the impacted tooth. Different Von Mises stress values were determined. Results Stress distribution on the periodontal ligament increased with traction size. When 30 g traction was exerted on the labial inverted impacted maxillary central incisor, the Von Mises stress was 24 919.0 Pa, which was within the range of the optimum force and close to its maximum value. Conclusion The optimum traction for early orthodontic treatment of labial inverted impacted maxillary central incisor is nearly 30 g.

  5. Surgical exposure dan perawatan ortodontik pada impaksi gigi insisif sentral rahang atas (Surgical exposure and orthodontic treatment on labially impacted maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Bingah Fitri Melati

    2014-06-01

    Full Text Available Background: As a clinician we have to concern for an unerupted teeth especially in mixed dentition. Eruption failure can also be caused by early loss of deciduous teeth. Purpose: To report a case of unerupted maxillary central incisor caused by early loss of deciduous teeth due to trauma and the combination of excisional and orthodontic treatment. Case: A 8-years-old girl in mixed dentition phase came to Universitas Airlangga Dental Hospital with chief complaint of unerupted right maxillary central incisor while the left central incisor and both lateral incisor had erupted already. She had trauma when she was 1 year old and loss mostly her primary maxillary central incisors. An intraoral examination revealed lack of space in #11 region with root retained of #51, bulge was palpated in vestibulum and periapical radiograph showed that a delayed eruption upper central incisor without presence of disturbance. Case management: The exposure of the tooth was under local anesthesia a year after the orthodontic performed to make enough space for traction the tooth. A button was placed at palatal and used elastic strait to traction the tooth. After 3 months, bracket placed at labial to positioning until leveled and aligned with adjacent teeth. Conclusion: A simple excisional and orthodontic treatment were succesfully treated the labially impacted teeth.Latar belakang: Sebagai seorang klinisi kita harus memperhatikan apabila terdapat gigi yang belum erupsi terutama pada fase gigi pergantian. Kegagalan erupsi gigi juga dapat disebabkan karena tanggal premature gigi sulung. Tujuan: Melaporkan kasus impaksi gigi insisif sentral rahang atas yang disebabkan kehilangan premature gigi sulung karena trauma dengan kombinasi eksisi sederhana dan perawatan ortodontik. Kasus: Anak perempuan usia 8 tahun pada fase gigi pergantian datang ke Rumah Sakit Gigi dan Mulut Universitas Airlangga dengan keluhan gigi insisif sentral kanan rahang atasnya (#11 belum erupsi meskipun

  6. 3D FEA of cemented glass fiber and cast posts with various dental cements in a maxillary central incisor.

    Science.gov (United States)

    Madfa, Ahmed A; Al-Hamzi, Mohsen A; Al-Sanabani, Fadhel A; Al-Qudaimi, Nasr H; Yue, Xiao-Guang

    2015-01-01

    This study aimed to analyse and compare the stability of two dental posts cemented with four different luting agents by examining their shear stress transfer through the FEM. Eight three-dimensional finite element models of a maxillary central incisor restored with glass fiber and Ni-Cr alloy cast dental posts. Each dental post was luted with zinc phosphate, Panavia resin, super bond C&B resin and glass ionomer materials. Finite element models were constructed and oblique loading of 100 N was applied. The distribution of shear stress was investigated at posts and cement/dentine interfaces using ABAQUS/CAE software. The peak shear stress for glass fiber post models minimized approximately three to four times of those for Ni-Cr alloy cast post models. There was negligible difference in peak of shear stress when various cements were compared, irrespective of post materials. The shear stress had same trend for all cement materials. This study found that the glass fiber dental post reduced the shear stress concentration at interfacial of post and cement/dentine compared to Ni-Cr alloy cast dental post. PMID:26543733

  7. Influence of post and resin cement on stress distribution of maxillary central incisors restored with direct resin composite.

    Science.gov (United States)

    Spazzin, A O; Galafassi, D; de Meira-Júnior, A D; Braz, R; Garbin, C A

    2009-01-01

    The current study evaluated the influence of two endodontic post systems and the elastic modulus and film thickness of resin cement on stress distribution in a maxillary central incisor (MCI) restored with direct resin composite using finite element analysis (FEA). A three-dimensional model of an MCI with a coronary fracture and supporting structures was performed. A static chewing pressure of 2.16 N/mm2 was applied to two areas on the palatal surface of the composite restoration. Zirconia ceramic (ZC) and glass fiber (GF) posts were considered. The stress distribution was analyzed in the post, dentin and cement layer when ZC and GF posts were fixed to the root canals using resin cements of different elastic moduli (7.0 and 18.6 GPa) and different layer thicknesses (70 and 200 microm). The different post materials presented a significant influence on stress distribution with lesser stress concentration when using the GF post. The higher elastic modulus cement created higher stress levels within itself. The cement thicknesses did not present significant changes. PMID:19363979

  8. The Effects of Post Diameter on Stress Distribution in Maxillary Central Incisor, A Three Dimensional Finite Element Study

    Directory of Open Access Journals (Sweden)

    A. Monzavi

    2004-06-01

    Full Text Available Statement of Problem: Currently there are three recognized theories about the diameter of prepared dowel space in endodontically treated teeth. Diameter of the dowel is commonly contributed to the root fracture.Purpose: This study used a 3 dimensional (3D finite element method to predict stress distribution in endodontically treated central maxillary tooth with cast post and core with various post diameter according to three philosophies about post diameter (Conservational,Proportional, Preservational.Materials and Methods: In this study three 3D models of central maxillary incisors with different post diameter were created and depend on the size of post called narrow, medium and thick model with post diameter of 1.1mm, 1.7 mm and 2.6 mm of in (CEJrespectively. A load of 100 N was applied to cingulum fossa from lingual direction with 45-degree angle to long axis of tooth and maximum tensile, compressive and Von Misses stresses and their distribution in dentin and post was studied.Results: The post in narrow, medium and thick models produced a similar magnitude of tensile, compressive and Von Misses stresses in dentin. Stress distribution was also similar in all models. Peak stresses in dentin were slightly decreased when post diameter increased from narrow to thick model. In all models peak tensile stresses in dentin occurred in the coronally one third of the lingual surface of the root, whereas peak compressive stresseswere evident in the coronal one third of the facial surface of the root.Conclusion: There were not significant differences stress distribution pattern and magnitude in dentin between the three theories of post diameter.

  9. Amalgamation of allogenic bone graft, platelet-rich fibrin gel, and PRF membrane in auto-transplantation of an impacted central incisor.

    Science.gov (United States)

    Chaudhary, Zainab; Kumar, Yuvika Raj; Mohanty, Sujata; Khetrapal, Ambica

    2015-01-01

    "Social six" teeth refers to the maxillary incisors and canines that play a vital role in the appearance of an individual and absence of any one of them has a significant psycho-social impact. Hence, early treatment and rehabilitation of the same are extremely important. A multitude of treatment options ranging from orthodontic extrusion, extraction followed by implant placement, fixed partial denture, and auto-transplantation have been advocated. This case report discusses the unique amalgamation of platelet-rich fibrin (PRF), demineralized freeze-dried bone graft with use of PRF membrane during auto-transplantation of an impacted central incisor. The authors have focused on maximum usage of autogenous materials in the most economic and least invasive manner. Furthermore, this amalgamation has been used to provide rehabilitation in the least span of time.

  10. Amalgamation of allogenic bone graft, platelet-rich fibrin gel, and PRF membrane in auto-transplantation of an impacted central incisor

    Directory of Open Access Journals (Sweden)

    Zainab Chaudhary

    2015-01-01

    Full Text Available "Social six" teeth refers to the maxillary incisors and canines that play a vital role in the appearance of an individual and absence of any one of them has a significant psycho-social impact. Hence, early treatment and rehabilitation of the same are extremely important. A multitude of treatment options ranging from orthodontic extrusion, extraction followed by implant placement, fixed partial denture, and auto-transplantation have been advocated. This case report discusses the unique amalgamation of platelet-rich fibrin (PRF, demineralized freeze-dried bone graft with use of PRF membrane during auto-transplantation of an impacted central incisor. The authors have focused on maximum usage of autogenous materials in the most economic and least invasive manner. Furthermore, this amalgamation has been used to provide rehabilitation in the least span of time.

  11. A comparative study to evaluate the vertical position of maxillary central incisor and canine in relation to incisive papilla line

    Directory of Open Access Journals (Sweden)

    Mayank Shah

    2014-01-01

    Full Text Available Objectives: The aim of the study was to determine the vertical distance of maxillary central incisor (CI and maxillary canine (CA from the incisive papilla (IP line and their variation with age and sex. Materials and Methods: A total of 120 dentulous subjects following the inclusion and exclusion criteria were randomly selected from the local population. On the basis of gender and age, subjects were divided into four groups: M a , M b , F a and F b . Maxillary impressions of selected subjects were made and corresponding casts were retrieved. The cast was positioned on the surveyor and the center of IP was transferred to the labial side of maxillary right CI and CA regions with the help of analyzing rod of the surveyor and a line was drawn in this region which was referred to as "IP line." The measurements were made from the IP line to the mesio-incisal line angle of right maxillary CI-IP and cusp tip of right maxillary CA with the help of digital vernier caliper (CA to IP. Result: The mean vertical distance of maxillary CI-IP ranged from 6.31 ± 0.74 mm to 7.04 ± 0.87 mm and the mean vertical distance of maxillary CA-IP ranged from 5.83 ± 0.80 mm to 6.30 ± 0.82 mm. Conclusion: The CA position in relation to the IP line is more stable to its position than the CI position irrespective of age and sex.

  12. Effect of labiolingual inclination of a maxillary central incisor and surrounding alveolar bone loss on periodontal stress: A finite element analysis

    Science.gov (United States)

    Choi, Sung-Hwan; Kim, Young-Hoon; Lee, Kee-Joon

    2016-01-01

    Objective The aim of this study was to investigate whether labial tooth inclination and alveolar bone loss affect the moment per unit of force (Mt/F) in controlled tipping and consequent stresses on the periodontal ligament (PDL). Methods Three-dimensional models (n = 20) of maxillary central incisors were created with different labial inclinations (5°, 10°, 15°, and 20°) and different amounts of alveolar bone loss (0, 2, 4, and 6 mm). The Mt/F necessary for controlled tipping (Mt/Fcont) and the principal stresses on the PDL were calculated for each model separately in a finite element analysis. Results As labial inclination increased, Mt/Fcont and the length of the moment arm decreased. In contrast, increased alveolar bone loss caused increases in Mt/Fcont and the length of the moment arm. When Mt/F was near Mt/Fcont, increases in Mt/F caused compressive stresses to move from a predominantly labial apical region to a palatal apical position, and tensile stresses in the labial area moved from a cervical position to a mid-root position. Although controlled tipping was applied to the incisors, increases in alveolar bone loss and labial tooth inclination caused increases in maximum compressive and tensile stresses at the root apices. Conclusions Increases in alveolar bone loss and labial tooth inclination caused increases in stresses that might cause root resorption at the root apex, despite the application of controlled tipping to the incisors. PMID:27226961

  13. Esthetic restoration of primary incisors.

    Science.gov (United States)

    Carranza, F; García-Godoy, F

    1999-04-01

    A simple and esthetic technique for restoring cariously involved primary maxillary incisors is described. The technique includes mini-pins, a preformed celluloid crown and resin-based composite. PMID:10477982

  14. Finite elements study of the Flexi Post and Flexi Flange post systems in a maxillary central incisor Estudo pelo método dos elementos finitos dos pinos Flexi Post e Flexi Flange em um incisivo central superior

    OpenAIRE

    Hugo Roberto Lewgoy; Michel Nicolau Youssef; Maurício Rufaiel Matson; Jorge Antônio Javier Saldivar Bocangel; Camillo Anauate Netto; Ricardo Amore

    2003-01-01

    The use of post and core systems has become an excellent alternative for restoring endodontically treated teeth. The aim of this study was to evaluate the von Mises, maximal compressive and tensile stresses distribution using the Finite Element Method (FEM) on human teeth restored with different post and core systems. The analysis was made on endodontically treated maxillary central incisors. The post systems used in this investigation were the stainless steel or titanium Flexi Post/Flexi Fla...

  15. 上颌中切牙埋伏阻生的临床分析%Clinical analysis of maxillary central incisors with impaction

    Institute of Scientific and Technical Information of China (English)

    陈琳; 钟燕雷; 郭红梅; 田春娟

    2012-01-01

    Objective To analyze the incidence,etiology and clinical treatment of the impacted maxillary central incisors.Methods A retrospective study was conducted on 29 cases of impacted maxillary central incisors that were randomly selected from the 1000 patients.Age of the patient was ranged from 7 to 23 years with median 11.1 years.Numbers of impacted teeth were 32,in which 22teeth were intraosseous impaction and others were extraosseous.The incidence,etiology,sites and direction of impacted teeth and their treatment approaches were explored in this study.Results Impac tion of maxillary central incisors occurred more frequently in females than in males,with a ratio of 1.0 ∶ 1.2.The ratio of intraosseous impaction to extraosseous one was 11 ∶ 5.The insufficient eruption space of maxillary central incisors was present in 65% patients,but intermediate and severe crowded teeth only accounted for 15%.The incidence of the abnormal site and position of impacted teeth reached 71 %.The clinical approach and solution were surgical-orthodontic treatment,transplantation or removal of impacted teeth.Conclusions The main cause is abnormity of teeth in the shape and position.Most of the impacted maxillary central incisors could be moved to the correct position by effective treatment.%目的 分析上颌中切牙埋伏阻生的发病率、病因及治疗结果,以期对临床治疗有所帮助.方法 随机抽取的1000例患者中确诊29例为上颌中切牙埋伏阻生,年龄为7~23岁,平均11.1岁.埋伏牙总数32枚,骨内埋伏有22枚,骨外埋伏10枚.对临床发病率、病因、埋伏阻生的位置和方向以及临床治疗方法和结果等方面进行回顾性研究.结果 男性发病率小于女性,男∶女为1.0∶ 1.2,骨内埋伏阻生与骨外之比为11∶5.有65%的患者存在上颌中切牙萌出间隙不足,但是属于中重度拥挤的仅占15%.埋伏牙自身形态和位置异常的发病率高达71%.临床治疗方法

  16. Evaluation of the mineralization degree of the vestibular surface of the upper central incisors with a 655-nm diode laser in mouth breathers: preliminary results

    Science.gov (United States)

    Pinheiro Ladalardo, Thereza C. C. G.; Cappellette, Mario, Jr.; Zanin, Fatima A. A.; Brugnera, Aldo, Jr.; Anthero de Azevedo, Ramiro; Pignatari, Shirley; Weckx, Luc L. M.

    2003-06-01

    Mouth breathing unbalances the physiological mechanisms of the dental surface hydration by compromising lip closure, and, very often, causing the vestibular positioning of upper incisors. That variance leads to the interruption of the dental demineralization and remineralization feedback, prevailing a demineralized condition of the dental surface which increases caries risk. The laser fluorescence examination allows an early demineralization diagnosis, thus it makes possible through preventive measures to minimize the risk factor - dental mineral structure loss - in the bacterial infection of the demineralized area, and hence, preventing invasive therapeutical procedures. A DIAGNOdent apparatus was used to evaluate the mineralization degree of the upper central incisors in 40 patients - twenty of them with a mouth breathing diagnosis; the remaining twenty were nasal breathers (control group). Age ranging from 6 to 12 years, both male and female. To measure the vestibular surface of the incisors, it was divided into 3 segments: cervical, medial and incisal. The average of the results pertaining to the mouth breathing patients was as follows: tooth 11 cervical third - 5.45, medial third - 7.15, incisal third - 7.95, and tooth 21 - cervical third - 5.95, medial third - 7.25, incisal third - 8.15. The control patients, nasal breathers, presented the following results: tooth 11 cervical third - 1.75, medial third - 2.30, incisal third - 1.85, and tooth 21 - cervical third - 1.80, medial third - 2.20, incisal third - 2.15. The mouth breathing patients showed demineralization in the teeth examined at the initial stage, subclinical, comparing with the control patients, nasal breathers, who did not present any mineral deficit in these teeth.

  17. Endodontic and Esthetic Management of a Dilacerated Maxillary Central Incisor Having Two Root Canals Using Cone Beam Computed Tomography as a Diagnostic Aid

    Directory of Open Access Journals (Sweden)

    Sarang Sharma

    2014-01-01

    Full Text Available Traumatic injuries to the primary dentition are quite common. When primary teeth are subjected to trauma, force transmission and/or invasion of the underlying tooth germs lying in close proximity can result in a variety of disturbances in the permanent successors. Few of these disturbances include hypoplasia, dilaceration, or alteration in the eruption sequence and pattern. Dilaceration is defined as an angulation or sharp bend or curve in the linear relationship of the crown of a tooth to its root. A rare case of maxillary left central incisor having crown dilaceration and Vertucci’s type II canal configuration with symptomatic periapical periodontitis is reported. Cone beam computed tomography was used for better understanding of the anomaly and complicated root canal morphology. The tooth was successfully managed by nonsurgical root canal therapy and restoration with resin composite to restore esthetics.

  18. Macrodontic maxillary incisor in alagille syndrome

    Directory of Open Access Journals (Sweden)

    Mauro Cozzani

    2012-01-01

    Full Text Available This case report describes the surgical-orthodontic guided-eruption of a deeply impacted macrodontic maxillary central incisor in a 10-year-old patient with Alagille syndrome (ALGS. In the first stage, orthodontic treatment with fixed appliance on deciduous teeth allowed to create enough space for the eruption of the maxillary right central incisor. The second stage included closed surgical exposure and vertical traction. After impacted tooth erupted in the proper position, accessory periodontal treatment and dental reshaping procedures may be indicated to camouflage macrodontic incisor with the adjacent teeth. This is the first report that presents a patient with ALGS undergoing orthodontic and surgical treatment.

  19. Endodontic treatment of a geminated maxillary incisor

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo da Silveira Bueno

    2011-04-01

    Full Text Available Introduction: Gemination is a tooth anomaly caused when a single tooth bud attempts to divide. This results in a tooth with a size greater than normal, but with only one root canal. Therefore, due to its features and singularities, this geminated tooth demands careful attention for endodontic treatment Objective and case report: The purpose of this case report is to describe the endodontic treatment of a geminated maxillary central incisor. Conclusion: A good planning of all treatment stages, based on a careful clinical and radiographic examination, it is essential to reach the success in the endodontic treatment of geminated teeth.

  20. 正畸患者对女性上颌中切牙和侧切牙牙龈高度不对称的审美评价%Esthetic perception of female maxillary central incisor and lateral incisor gingival margin asymmetries for orthodontic patients

    Institute of Scientific and Technical Information of China (English)

    曹芳; 吴丽霞; 王臻

    2016-01-01

    Objective To investigate the esthetic perceptions of female maxillary central incisor and lateral incisor gingival margin asymmetries for orthodontic patients. Methods Female maxillary central incisor and lateral incisor gingival margin asymmetries models were set up. The distance from the gingival margin of the center incisor and lateral incisor to the incisor edge was set as 0.5 mm, 1.0 mm, 1.5 mm and 2.0 mm. A questionnaire was designed to investigate the esthetic perceptions of gingival margin asymmetries. Results In general, the most attractive smiles for the orth⁃odontic patients were the ones without asymmetries or with a 0.5⁃1.0 mm asymmetry (P < 0.05). The patients could be initiated the difference by an asymmetry of 1.0 mm, and the asymmetries with 1.5⁃2.0 mm were not acceptable for anes⁃thetics (P < 0.05). Conclusion The perceptions of anesthetic asymmetries in the gingival margin levels of the female maxillary central incisor and lateral incisor gingival margin were 1.0⁃1.5 mm, and this statics is somewhat clinically in⁃structive.%目的:调查正畸患者对女性上颌中切牙和侧切牙牙龈高度变化的关注程度和审美评价。方法建立女性上颌中切牙和侧切牙牙龈向切端偏移的模型(上颌中切牙和侧切牙牙龈向切端偏移0.5 mm、1.0 mm、1.5 mm和2 mm),利用调查问卷对正畸患者进行调查。结果上颌中切牙和侧切牙左右牙龈对称和上颌中切牙牙龈向切端偏移0.5 mm时,是患者认为最美观的笑容;上颌中切牙和侧切牙牙龈向切端偏移1.0 mm时,患者开始察觉上颌中切牙和侧切牙牙龈不对称(P<0.05);上颌中切牙和侧切牙牙龈向切端偏移1.5 mm到2.0 mm时,患者认为已经影响了美观和笑容(P<0.05)。结论上颌中切牙和侧切牙牙龈不对称的牙龈高度变化1.0 mm到1.5 mm以上时,患者开始察觉和开始认为影响了美观和笑容。

  1. 上颌正中孤立中切牙综合征1例报告%Solitary median maxillary central incisor syndrome: a case of report

    Institute of Scientific and Technical Information of China (English)

    康丽颖; 刘新强

    2014-01-01

    上颌正中孤立中切牙(solitary median maxillary central incisor,SMMCI)是一种比较罕见的牙畸形,是指在上颌牙弓中仅发育并萌出1颗中切牙且该中切牙位于牙弓的正中,形态左右对称,大小与正常中切牙相似,在乳、恒牙列均可见.SMMCI可单独发生,也可伴发其他先天性中线结构畸形,或与一些系统性疾病同时发生.其中,与前脑无裂畸形(holoprosencephaly,HPE)关系最为密切.本文报告1例伴有其他中线结构缺陷的上颌正中孤立中切牙病例.并对相关问题进行讨论.

  2. Estimation of the rate of tooth wear in permanent incisors: a cross-sectional digital radiographic study.

    Science.gov (United States)

    Ray, D S; Wiemann, A H; Patel, P B; Ding, X; Kryscio, R J; Miller, C S

    2015-06-01

    This study used conventional digital radiography to estimate the rate of tooth wear (TW) of maxillary and mandibular central incisors based on a cross-sectional study design. The crown length of 1239 permanent maxillary and mandibular central incisors from 346 persons (age groups: 10, 25, 40, 55 and 70 years ± 3) were measured by three calibrated dentists. Study teeth were intact incisally, had clearly visible incisal edges and cementoenamel junctions and had natural tooth antagonists. Measures were based on digital radiographic images (N = 666) archived in MiPACS within the electronic health record (axiUm(®)) from the College of Dentistry patient database. Incisor crown length decreased at a linear rate in both arches over the 60 years represented by the age groups. The average crown length for maxillary incisors in the youngest age group was 11.94 mm, which decreased by an average of 1.01 mm by median age 70. For mandibular incisors, the average crown length in the youngest age group was 9.58 mm, which decreased by an average of 1.46 mm in the oldest age group. Males and females showed similar rates of TW. Regardless of age, females demonstrated smaller mean crown height for maxillary incisors than males (P < 0.0001). Measures by the examiners demonstrated good agreement, with an interclass correlation coefficient of 0.869 and an average intra-examiner correlation of 99.5%, based on repeated measurements (n = 100). TW was estimated to average 1.01 mm for maxillary central incisors and 1.46 mm for mandibular central incisors by age 70 years. PMID:25756187

  3. Color changes of vital central upper incisor after chairside heat bleaching%活体上颌中切牙加热漂白后的颜色值变化

    Institute of Scientific and Technical Information of China (English)

    周俊杰; 谢海峰; 陈晨

    2014-01-01

    AIM:To evaluate the color changes of healthy central upper incisor after chairside bleaching. METHODS:Color changes of 16 healthy central upper incisors before and after chairside heat bleaching by wy10 were determined using a dental colorimeter,and color difference values were calculated.RESULTS:Color difference values were 4.23 ±2.21 after bleaching.Paired t-test showed that L* parameter of the central upper incisors increased (P<0.05)and b* parameters decreased (P<0.05)after bleaching.CONCLUSION:Chairside heat bleaching re-sult in lighter and blue-converse of healthy central upper incisors.%目的:观察患者接受牙齿椅旁恒温外漂白治疗后健康上颌中切牙的颜色值变化。方法:利用牙科色度计采集16例健康上颌中切牙漂白前后的L*、a*、b*颜色参数值,分析各参数的变化以及计算漂白后牙齿颜色变化的色差值。结果:漂白后牙色平均改善了6±3个色阶。漂白前后的色差值为4.23±2.21。配对t检验结果显示,上颌中切牙漂白后L*值显著增加,b*值显著降低,a*值无明显变化趋势。结论:牙齿椅旁恒温外漂白治疗能够增加健康上颌中切牙的明度,颜色向蓝色转变。

  4. Lower molar and incisor displacement associated with mandibular remodeling.

    Science.gov (United States)

    Baumrind, S; Bravo, L A; Ben-Bassat, Y; Curry, S; Korn, E L

    1997-01-01

    The purpose of this study was to quantify the amount of alveolar modeling at the apices of the mandibular incisor and first molar specifically associated with appositional and resorptive changes on the lower border of the mandible during growth and treatment. Cephalometric data from superimpositions on anterior cranial base, mandibular implants of the Björk type, and anatomical "best fit" of mandibular border structures were integrated using a recently developed strategy, which is described. Data were available at annual intervals between 8.5 and 15.5 years for a previously described sample of approximately 30 children with implants. The average magnitudes of the changes at the root apices of the mandibular first molar and central incisor associated with modeling/remodeling of the mandibular border and symphysis were unexpectedly small. At the molar apex, mean values approximated zero in both anteroposterior and vertical directions. At the incisor apex, mean values approximated zero in the anteroposterior direction and averaged less than 0.15 mm/year in the vertical direction. Standard deviations were roughly equal for the molar and the incisor in both the anteroposterior and vertical directions. Dental displacement associated with surface modeling plays a smaller role in final tooth position in the mandible than in the maxilla. It may also be reasonably inferred that anatomical best-fit superimpositions made in the absence of implants give a more complete picture of hard tissue turnover in the mandible than they do in the maxilla.

  5. Orthodontic management of an impacted maxillary incisor due to odontoma

    Directory of Open Access Journals (Sweden)

    Rahul S Baldawa

    2011-01-01

    Full Text Available Odontomas are a heterogeneous group of jaw bone lesions, classified as odontogenic tumors which usually include well-diversified dental tissues. Odontomas are the most common type of odontogenic tumors and generally they are asymptomatic. Two types of odontomas are described: compound and complex based on either the appearance of well-organized tooth-like structures (compound odontomas or on a mass of disorganized odontogenic tissues (complex odontomas. Compound odontomas have a predilection for the anterior maxilla, whereas complex odontomas have a predilection for the posterior mandible. Odontomas frequently interfere with eruption of teeth leading to their impaction. This is a case report of a 14-year-old girl with an unerupted maxillary right central incisor due to a complex composite odontoma a rare occurrence in anterior maxilla. Surgical excision of the odontoma and orthodontic treatment to get the impacted maxillary right central incisor into alignment is discussed.

  6. 上颌中切牙阻生对颅面结构的影响及其矫治%Influence of impacted maxillary central incisor on craniofacial structure and its orthodontic treatment

    Institute of Scientific and Technical Information of China (English)

    雷浪; 柯晓菁; 李厚轩; 李煌; 闫福华

    2016-01-01

    目的:研究上颌中切牙埋伏阻生对颅面结构的影响并探讨其矫治方法。方法63例上颌中切牙埋伏阻生的病例,按照其牙列发育情况分为混合牙列组(32例)和恒牙列组(31例)。描记所有患者的头颅侧位片,测量15项角度和6项线距,将其测量值与对应的正常牙合对照组进行比较。结果上颌切牙埋伏病例的发病因素中,多生牙、含牙囊肿或牙瘤、外伤和不明原因各占6.3%、6.3%、12.4%和73%。头影测量显示上颌中切牙阻生病例SNA和ANB角较对照组显著减小(P<0.05),并伴有牙性变化即上颌切牙唇倾、下颌切牙舌倾(P<0.05)。在牙根发育早期( Nolla法第7期和第8期),13颗埋伏切牙中12颗正畸牵引成功;在牙根发育晚期(第9期和第10期),15颗埋伏切牙中7颗牵引成功。结论上颌中切牙埋伏阻生后,上颌发育受限;早期矫治可以提高埋伏牙成功率,同时有利于牙根发育。%Objective To explore the influence of impacted maxillary central incisor on craniofacial structure and its orthodontic treatment. Methods A total of 63 subjects with impacted upper central incisors were selected and catego-rized into the mixed ( n=32) and permanent dentition group ( n=31) . By using the lateral cephalograms of each subject, 15 angular and 6 linear measurements were made. The cephalometric data were analyzed and compared to data of its cor-responding control group with normal occlusion. Results Among the etiological factors of all 63 cases with impacted up-per incisors, supernumerary teeth, dentigerous cyst or odontoma, mechanical trauma and idiopathic factors comprise of 6. 3%, 6. 3%, 12. 4% and 73% respectively. Cephalometric analysis demonstrated a more retruded position of"A" point with decreased SNA and ANB angle in incisor impaction group. Dental compensations followed the decreased ANB angle with more proclined upper incisor and more upright lower incisor. In early stage of root development

  7. Contour changes in human alveolar bone following tooth extraction of the maxillary central incisor%人类上颌中切牙拔除后牙槽骨外形变化的研究

    Institute of Scientific and Technical Information of China (English)

    Bei LI; Yao WANG‡

    2014-01-01

    The purpose of this study was to apply cone-beam computed tomography (CBCT) to observe contour changes in human alveolar bone after tooth extraction of the maxillary central incisor and to provide original mor-phological evidence for aesthetic implant treatment in the maxilary anterior area. Forty patients were recruited into the study. Each patient had two CBCT scans (CBCT I and CBCT II), one taken before and one taken three months after tooth extraction of maxillary central incisor (test tooth T). A fixed anatomic reference point was used to orient the starting axial slice of the two scans. On three CBCT I axial slices, which represented the deep, middle, and shallow layers of the socket, labial and palatal alveolar bone widths of T were measured. The number of sagittal slices from the start point to the pulp centre of T was recorded. On three CBCT II axial slices, the pulp centres of extracted T were oriented according to the number of moved sagittal slices recorded in CBCT I. Labial and palatal alveolar bone widths at the oriented sites were measured. On the CBCT I axial slice which represented the middle layer of the socket, sagittal slices were reconstructed. Relevant distances of T on the sagittal slice were measured, as were the alveolar bone width and tooth length of the opposite central incisor. On the CBCT II axial slice, which represented the middle layer of the socket, relevant distances recorded in CBCT I were transferred on the sagittal slice. The height reduction of alveolar bone on labial and palatal sides was measured, as were the alveolar bone width and tooth length of the opposite central incisor at the oriented site. Intraobserver reliability assessed by intraclass correlation coefficients (ICCs) was high. Paired samplet-tests were performed. The alveolar bone width and tooth length of the opposite central incisor showed no statistical differences (P<0.05). The labial alveolar bone widths of T at the deep, middle, and shalow layers al showed

  8. 埋伏弯根上颌中切牙序列矫治的研究%Sequence orthodontic treatment of impacted dilacerated maxillary central incisors

    Institute of Scientific and Technical Information of China (English)

    郑怡; 庞煊奈; 南澜; 莫水学

    2012-01-01

    目的 探讨埋伏弯根上颌中切牙有效的正畸牵引治疗方法.方法 选择11例患者共12颗埋伏弯根上颌中切牙为研究对象,常规拍摄定位X线片,配合口内检查、模型分析等,确定埋伏牙的位置及其与邻牙的相互关系,采用封闭式导萌、选择性根管治疗及根尖切除术、修复治疗等方法进行矫治.结果 12颗埋伏牙通过治疗后顺利进入正常牙列,未见牙根吸收粘连,建立了良好的咬合关系.9例唇侧埋伏弯根上颌中切牙患者的临床牙冠唇倾角度较大,4例根尖位于唇侧黏膜下,进行了根管治疗加根尖切除术,其中1例行烤瓷冠改形修复;其余5例未做根管治疗,暂行观察.2例腭侧埋伏弯根上颌中切牙的疗效稳定.结论 埋伏弯根上颌中切牙采用序列矫治可以取得良好的美观和功能效果.%Objective To explore an effective orthodontic method for treating impacted dilacerated maxillary central incisors. Methods 12 impacted teeth of 11 cases were chosen. The position of the impacted teeth and the relations with neighbour tissues weie assessed by X-ray images, oral examination and plaster model, etc. The impacted teeth were induced to erupt with the closed-eruption technique and fixed orthodontic appliances, root canal therapy, apicoectomy and prosthetic treatment. Results 12 impacted teeth were moved into arches, and the occlusal relationship was normal. There were no root resorption or conglutination in those impacted teeth. The labial impacted teeth of nine cases had bigger labial crown torsion. The root apexes of four impacted teeth were palpable under mucosa of the labial sulcus and operated by root canal therapy and apicoectomy. One of them received prosthetic treatment Others (five cases) hadn't accepted root canal therapy, and were observed temporarily. The effects of two palatal impacted teeth was stable. Conclusion It was a good method to expand indication with sequence orthodontic treatment. The

  9. Dental trauma clinically mimicking single central incisor syndrome = Traumatismo dentário mimetizando clinicamente a síndrome do incisivo central único

    OpenAIRE

    Moreira, Rafaela Nogueira

    2012-01-01

    Objetivo: Apresentar um caso clínico de ausência de um incisivo central perdido por traumatismo e encaminhado ao ortodontista com suspeita de apresentar síndrome do incisivo central único (SMMCI). Descrição do caso: Paciente gênero feminino, 12 anos com queixa da aparência de seus dentes. Ao exame intrabucal observou-se a presença de um incisivo central único localizado na linha média sem espaçamentos em relação aos incisivos laterais superiores. A paciente relatou dois episódios de avulsã...

  10. Surgical endodontic management of infected lateral canals of maxillary incisors

    Science.gov (United States)

    2015-01-01

    This case report presents surgical endodontic management outcomes of maxillary incisors that were infected via the lateral canals. Two cases are presented in which endodontically-treated maxillary central incisors had sustained lateral canal infections. A surgical endodontic treatment was performed on both teeth. Flap elevation revealed vertical bone destruction along the root surface and infected lateral canals, and microscopy revealed that the lateral canals were the origin of the lesions. After the infected lateral canals were surgically managed, both teeth were asymptomatic and labial fistulas were resolved. There were no clinical or radiographic signs of surgical endodontic management failure at follow-up visits. This case report highlights the clinical significance and surgical endodontic management of infected lateral canal of maxillary incisor. It is important to be aware of root canal anatomy variability in maxillary incisors. Maxillary central incisors infected via the lateral canal can be successfully managed by surgical endodontic treatment. PMID:25671217

  11. Association between Molar Incisor Hypomineralization in Schoolchildren and Both Prenatal and Postnatal Factors: A Population-Based Study

    Science.gov (United States)

    Corrêa-Faria, Patrícia; Ferreira, Raquel Conceição; Bendo, Cristiane Baccin; Zarzar, Patrícia Maria; Vale, Miriam Pimenta

    2016-01-01

    Background Although studies throughout the world have investigated potential factors involved in the occurrence of molar incisor hypomineralization (MIH), the findings are varied and inconclusive. Objective The aim of the present study was to evaluate the prevalence of MIH and identify associated prenatal, perinatal and postnatal factors among Brazilian schoolchildren aged 8 and 9 years. Methods A cross-sectional study was conducted with a randomly selected population-based sample of 1181 schoolchildren. Information on demographic and socioeconomic characteristics as well as prenatal, perinatal and postnatal aspects was obtained through questionnaires. The clinical examination included the investigation of MIH based on the criteria of the European Academy of Paediatric Dentistry. Dental caries in the permanent dentition and developmental defects of enamel (DDE) on the primary second molars were also recorded. Data analysis involved descriptive statistics, bivariate tests and Poisson regression with robust variance. Results The prevalence of MIH was 20.4%. MIH was more frequent among children with dental caries in the permanent dentition (PR: 2.67; 95% CI: 1.98–3.61), those with DDE on the primary second molars (PR: 2.54; 95% CI: 1.87–3.45) and those who experienced asthma/bronchitis in the first four years of life (PR: 1.93; 95% CI: 1.45–2.56). Conclusions The prevalence of MIH was high and was associated with dental caries, the presence of DDE on primary second molars and the experience of asthma/bronchitis in early life. These findings could be useful in the identification of children in need of shorter recall intervals to prevent the consequences of MIH, such as enamel breakdown dental caries. PMID:27280451

  12. Síndrome do incisivo central superior solitário: relato de caso Solitary median maxillary central incisor syndrome: case report

    OpenAIRE

    Eduardo Machado; Patricia Machado; Betina Grehs; Renésio Armindo Grehs

    2010-01-01

    INTRODUÇÃO: a presença de um incisivo central superior solitário é um evento bastante incomum na população. A prevalência da chamada Síndrome do Incisivo Central Superior Solitário (SICSS) é verificada em 1:50.000 nascimentos, sendo registrado um maior acometimento no sexo feminino. Essa alteração no desenvolvimento da oclusão dentária é caracterizada por más formações estruturais, sobretudo na região de linha média do paciente. O diagnóstico precoce e o tratamento adequado dessa síndrome são...

  13. The Geometric Feature Study of Maxillary Central Incisor of 101 Han Nationality Persons in Northeast of China%101例中国东北汉族上颌中切牙几何特征的研究

    Institute of Scientific and Technical Information of China (English)

    刘明丽; 陈小冬; 王勇

    2012-01-01

    Objective: To obtain dimension and analyze geometry shape of maxillary central incisor clinical crown, providing the reference to the tooth esthetics rehabilitation. Methods; The maxillary left central incisor of 101 volunteers were measured on the mesial -distal (width) and cervical-incisal (length) dimension. The lip surface shape was categorized into three groups (triangle round, rectangle and egg round). The incisal edge shape was categorized into three groups (the straight, the circular arc and the inverse-circular arc). The protrusion of lip surface was categorized into two groups (flatness and protrusion). Ail samples were sorted by sex and age, and analyzed using SPSS 13. 0 software. Results: By two independent samples T -test, the mature group incisor length was a little longer than the youth group, but didn't have statistical significance. The male incisor length was longer than the female, by two independent samples T-test, P<0. 05. By chi-square analysis the shape constituent ratio difference didn't have statistical significance between the male and female. Conclusion: The maxillary central incisor length of the male is a little longer than the female. Sex is not certainty relational to maxillary central incisor shape.%目的:研究上颌中切牙临床冠近远中径、切龈径与唇面形态,为前牙美学修复提供参考.方法:选取前牙列完整自愿者101例,测量左上中切牙近远中径、切龈径;并按尖圆,方正、卵圆形记录唇面总体形态,按平直、圆突、反圆弧记录切缘形态;以平坦、圆突记录唇面突度.按性别和年龄分组,SPSS 13.0分折研究结果.结果:经两独立样本T检验,壮年组的切龈径较青年组有所增加,但差异无统计学意义;男性切龈径大于女性,性别差异P<0.05,有统计学意义;近远中径、近远中径/切龈径比值,青年与壮年组、男女两性差异均无统计学意义.经卡方检验,中切牙唇面形态构成比性别差异无

  14. 正交试验法的上颌中切牙瓷贴面力学特性的有限元分析%Finite element analysis of maxillary central incisor porcelain veneer by orthogonal experiment

    Institute of Scientific and Technical Information of China (English)

    赵莹; 郑淑贤

    2011-01-01

    目的 综合上颌中切牙瓷贴面受力的主要因素,设计正交试验对其力学特性进行有限元分析,得出相对合理的瓷贴面设计方案.方法 制作开窗型、对接型、包绕型厚度分别为0.5、0.7、0.9mm的中切牙瓷贴面复合体,螺旋CT扫描后建立有限元模型,基于正交试验进行有限元分析,得出最佳应力分布条件下各因素参数的最优组合.结果 加载部位对应力的影响最大,其次为瓷贴面厚度、加载角度,切端设计类型最小;当加载角度为0°、厚度为0.9mm、加载部位为中1/3时对应力影响最小;开窗型、对接型瓷贴面的各部位的应力均大于包绕型,且于牙颈部存在较大应力集中区.结论 正常覆(糟)的患者为瓷贴面修复的最佳适应证;瓷贴面厚度对应力分布的影响较大;瓷贴面切端设计对应力的影响最不重要,但临床上尽可能选择包绕型设计;牙唇倾度对瓷贴面应力分布的影响较小,沿牙体长轴传导的力最有利.%Objective With consideration of the major load factors, the finite element analysis of the mechanics characteristics of maxillary central incisor was conducted by the method of orthogonal experiment, and then a relatively reasonable design plan of porcelain veneer was obtained. Methods Window, butt-joint and overlapped maxillary central incisor porcelain veneer complex which are 0.5mm、0.7mm、0.9mm respectively were made and the finite element model was established after spiral computed tomography scan. Followed by the finite element which was based on orthogonal experiment, the optimal combination of factor parameters under the circumstance of optimal stress distribution was found. Results Loading station had the greatest influence on the stress, followed by the thickness of porcelain veneer and loading angle; incisal design type has the least influence; the smallest influence on the stress was found under the circumstance of 0°(loading angle), central

  15. 椅旁操作次数对恒温漂白活体上中切牙疗效的影响%The effect of chairside heat bleaching times on healthy central upper incisors

    Institute of Scientific and Technical Information of China (English)

    奚晓菁; 章非敏; 谢海峰; 周俊杰

    2015-01-01

    Objective To study the effect of different chairside heat bleaching times on the healthy central upper incisors. Methods The subjects were treated with chairside heat bleaching for three times (an interval of one day),45 minutes each time. Color param-eters of the six healthy central upper incisors before and after each time of bleaching by Wy10 were determined using a dental colorime-ter and a VITA classical shade guide. The statistical analysis of the results was performed using paired t-test. Results Paired t-test showed that L* and W(Lab)parameters of all the central upper incisors increased(P 1. 7). Conclusions The increase in the number of operation times leads to the improvement of the heat bleaching effect.%目的:本实验旨在研究不同椅旁操作次数对活体上中切牙恒温漂白疗效的影响。方法受试者接受连续3次(每次间隔1 d)、每次45 min 的恒温漂白治疗,以比色仪测量每次漂白前后上中切牙的L*、a*、b*颜色参数值,分析变化,并记录比色板比色结果。所得数据以配对t 检验进行统计分析。结果统计分析显示,所有受试者接受漂白后牙体的L*、W (Lab)增大,b*降低,即牙齿的亮度和白度值增加,颜色向蓝色转变,且随漂白次数增多幅度变大,差别有统计学差异(P <0.05)。每次漂白操作后牙体颜色变化的色差均大于1.7个NBS 单位,说明每次漂白后的颜色变化均能被肉眼辨别。结论增加漂白次数能提高漂白疗效。

  16. Molar Incisor Hypomineralization, Prevalence, and Etiology

    Directory of Open Access Journals (Sweden)

    Sulaiman Mohammed Allazzam

    2014-01-01

    Full Text Available Aim. To evaluate the prevalence and possible etiological factors associated with molar incisor hypomineralization (MIH among a group of children in Jeddah, Saudi Arabia. Methods. A group of 8-12-year-old children were recruited (n=267  from the Pediatric Dental Clinics at the Faculty of Dentistry, King Abdulaziz University. Children had at least one first permanent molar (FPM, erupted or partially erupted. Demographic information, children’s medical history, and pregnancy-related data were obtained. The crowns of the FPM and permanent incisors were examined for demarcated opacities, posteruptive breakdown (PEB, atypical restorations, and extracted FPMs. Children were considered to have MIH if one or more FPM with or without involvement of incisors met the diagnostic criteria. Results. MIH showed a prevalence of 8.6%. Demarcated opacities were the most common form. Maxillary central incisors were more affected than mandibular (P=0.01. The condition was more prevalent in children with history of illnesses during the first four years of life including tonsillitis (P=0.001, adenoiditis (P=0.001, asthma (P=0.001, fever (P=0.014, and antibiotics intake (P=0.001. Conclusions. The prevalence of MIH is significantly associated with childhood illnesses during the first four years of life including asthma, adenoid infections, tonsillitis, fever, and antibiotics intake.

  17. An in vitro study of the quantity of tooth reduction for ceramic veneers of the human maxillary central incisor%人上颌中切牙全瓷贴面牙体预备量的研究

    Institute of Scientific and Technical Information of China (English)

    孙冠阳; 吴国锋; 张大鹏; 王嘉; 吴秦; 谢瑞

    2016-01-01

    AIM:To quantify the tooth structure reduction and the bonding area of one human maxillary central incisor preparation for ceramic veneers by Micro CT and 3-D printing technology.METHODS:According to the requirements of clinical experiments,one male maxillary central incisor with normal crown shape and without severe abrasion was selected.The tooth was scanned by Micro CT,then reconstructed into 3-D model and copied by 3-D printing method.Afterwards,veneers were prepared by clinical standards.Finally,The reverse engineering software of Mimics and Geomagic Studio were applied to analyze the volume and area of the dental tissue specimen before and after tooth preparation.RESULTS:The volume loss of maxillary central incisor after tooth preparation for veneer was 90.05 mm3 ,and the total bonding area was 107.27 mm2 (the bonding area of enamel was 60.84 mm2 ,56.71%).CON-CLUSION:The tissue loss of maxillary central incisor for porcelain laminate veneer accounts for about 1 /3 of the crown hard -tissue by volume.The mean percentage of enamel exposure following preparation is more than that of den-tine.The use of enamel bonding system during the placement of porcelain veneer is suggested.%目的:通过逆向工程和3D 打印技术精确测量1例人上颌中切牙行全瓷贴面的牙体预备量和牙体裸露面积。方法:临床收集健康人上颌中切牙1个,采用 Micro CT 对其进行三维扫描和重建,3D 打印方法将该上颌中切牙进行批量复制,然后按照临床标准进行全瓷贴面牙体预备;最后采用逆向工程软件对牙冠预备前后的牙体组织体积、裸露面积等指标进行测量分析。结果:上颌中切牙全瓷贴面牙体预备磨除的牙体组织体积均值为90.05 mm3;预备后牙冠的牙体裸露面积均值为107.27 mm2,其中釉质粘结面积为60.84 mm2,占预备体粘结面积的56.71%。结论:上颌中切牙瓷贴面牙体预备磨除量约占其牙冠硬组织体积的1

  18. Deciduous molar hypomineralization and molar incisor hypomineralization

    NARCIS (Netherlands)

    M.E.C. Elfrink; J.M. ten Cate; V.W.V. Jaddoe; A. Hofman; H.A. Moll; J.S.J. Veerkamp

    2012-01-01

    This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life until young adulthood. This study focused on the relationship between Deciduous Molar Hypomineralization (DMH) and Molar Incisor Hypomineralization (MIH). First permanent molars develop dur

  19. Intrusion of incisors in adult patients with marginal bone loss.

    Science.gov (United States)

    Melsen, B; Agerbaek, N; Markenstam, G

    1989-09-01

    Elongated and spaced incisors are common problems in patients suffering from severe periodontal disease. Thirty patients characterized by marginal bone loss and deep overbite were treated by intrusion of incisors. Three different methods for intrusion were applied: (1) J hooks and extraoral high-pull headgear, (2) utility arches, (3) intrusion bent into a loop in a 0.17 x 0.25-inch wire, and (4) base arch as described by Burstone. The intrusion was evaluated from the displacement of the apex, incision, and the center of resistance of the most prominent or elongated central incisor. Change in the marginal bone level and the amount of root resorption were evaluated on standardized intraoral radiographs. The pockets were assessed by standardized probing and the clinical crown length was measured on study casts. The results showed that the true intrusion of the center of resistance varied from 0 to 3.5 mm and was most pronounced when intrusion was performed with a base arch. The clinical crown length was generally reduced by 0.5 to 1.0 mm. The marginal bone level approached the cementoenamel junction in all but six cases. All cases demonstrated root resorption varying from 1 to 3 mm. The total amount of alveolar support--that is, the calculated area of the alveolar wall--was unaltered or increased in 19 of the 30 cases. The dependency of the results on the oral hygiene, the force distribution, and the perioral function was evaluated in relation to the individual cases. It was obvious that intrusion was best performed when (1) forces were low (5 to 15 gm per tooth) with the line of action of the force passing through or close to the center of resistance, (2) the gingiva status was healthy, and (3) no interference with perioral function was present.

  20. Effect of coffe and a cola-based soft drink on the color stability of bleached bovine incisors considering the time elapsed after bleaching

    Directory of Open Access Journals (Sweden)

    Rodrigo PIROLO

    2014-12-01

    Full Text Available There is no consensus about the waiting time necessary for the patient to start consuming beverages containing colorants again after bleaching. Objective: To evaluate the influence of beverages with coloring agents on bleached bovine incisors considering the time elapsed after bleaching. Materials and methods: Sixty bovine incisors were bleached with 35% hydrogen peroxide for in-office use (Whiteness HP Max and divided into 10 groups. The color was evaluated with a spectrophotometer (Spectro Shade MICRO before and after bleaching, employing the CIE-Lab system. After bleaching, the teeth were exposed for 5 min to coffee or cola-based soft drink (CBSD at different periods after bleaching: 10 min, 1 h, 24 h, 48 h, and 72 h. Color (∆E and lightness (∆L variations were obtained from the CIE-Lab coordinates. Data were subjected to two-way ANOVA and Tukey HSD tests (p<0.05. Results: Significant differences were observed between groups for both the ∆L and ∆E values (p<0.001. All specimens presented a decrease in brightness (negative ∆L. The highest ∆E values were observed for teeth stained with a CBSD at 10 min and 1 h (4.12 and 4.16, respectively. Teeth pigmented with coffee presented ∆E values below 3.3 units for all evaluation times. Conclusion: The exposure to coffee after bleaching causes less color changes than the exposure to a CBSD regardless of the time after bleaching.

  1. Molar Incisor Hypomineralization.

    Science.gov (United States)

    Rao, Murali H; Aluru, Srikanth C; Jayam, Cheranjeevi; Bandlapalli, Anila; Patel, Nikunj

    2016-01-01

    Molar incisor hypomineralization (MIH) is a developmental defect affecting teeth. High prevalence rates of MIH and its clinical implications are significant for both the patients and clinicians. A wide variation in defect prevalence (2.4-40.2%) is reported. It seems to differ with regions and various birth cohorts. Some of the recent prevalence studies are tabulated. Patient implications include hypersensitive teeth, rapid progression of caries, mastication impairment due to rapid attrition, and esthetic repercussions. Implications for clinicians include complexity in treatment planning and treatment implementation, poor prognosis of the restorations, difficulty in achieving pain control during treatment, and behavior management problems. Intention of this paper is to review the etio-pathogenesis, prevalence, clinical features, diagnostic features, and eventually present a sequential treatment approach, i.e., in accordance with current clinical practice guidelines. PMID:27595731

  2. 替牙期牵引上颌埋伏阻生中切牙的疗效观察%Evaluation of the orthodontic treatment outcome in patients with impacted maxillary central incisor in the mixed dentition

    Institute of Scientific and Technical Information of China (English)

    程灿; 李小彤; 刘鹤

    2016-01-01

    Objective To evaluate the orthodontic treatment outcome in patients with impacted maxillary central incisor in the mixed dentition.Methods Nine patients,aged 8 to 11 years,with impacted maxillary central incisor were treated orthodontically.The cone-beam CT(CBCT) was taken before treatment,after treatment and one year out of retention to evaluate the root length,root canal wall thickness,width of the apical foramen,and degree of root bending,alveolar bone height and thickness.The crown-to-root ratio was calculated.The periodontal and endodontic conditions were evaluated.The parameters of the treated incisors and contralateral ones served as controls were compared.Results Nine impacted teeth were treated successfully.Throughout the treatment,the root of impacted central incisor continued to develop and the alveolar bones also continued to develop and remodel.The condition of the alveolar bone of vertically impacted teeth was better than that of horizontally impacted ones.No periodontal pocket or pulp necrosis was found after treatment.Seven patients were examined one year after treatment.No significant difference was found in root length,palatal alveolar bone level and palatal alveolar bone thickness.The control group root length was (13.07±2.15) mm,the treatment group root length was (12.06±2.00) mm.No further alveolar bone loss,gingival recession and pulp necrosis were found.The control group labial and palatal alveolar bone levels were (0.90 ± 0.62),(0.45 ± 0.52) mm,labial and palatal alveolar bone thickness were (0.85 ±0.14),(1.21 ±0.41) mm.The treatment group labial and palatal alveolar bone levels were (2.18 ± 1.59) mm,(0.57 ± 0.71) mm,labial and palatal alveolar bone thickness were (0.48 ± 0.29),(1.43 ± 0.31) mm.Conclusions Orthodontic therapy for impacted maxillary central incisor in the mixed dentition could promote root development and alveolar bone remodeling.Good periodontal and endodontic conditions were achieved.%目的 在替牙期对埋伏

  3. Management of traumatically intruded permanent incisors

    Directory of Open Access Journals (Sweden)

    Shivayogi M

    2007-05-01

    Full Text Available Intrusive luxation of permanent teeth has great psychologic impact on both parents and children and presents clinical challenge for the dentist, all the more due to severe complications it is difficult to manage this group of dental injuries. This paper describes the management of traumatically intruded permanent maxillary-central incisor in an 11-year-old girl. After 12-month follow-up, it was seen that teeth were fully re-erupted and are in functional alignment with other teeth.

  4. The methodological study of improving the detected rate of mandibular central incisor with two canals%提高下中切牙双根管检出率的方法学研究

    Institute of Scientific and Technical Information of China (English)

    王晓丽; 徐怡; 孙青; 张遵

    2012-01-01

    目的:用5种不同方法对离体下颌中切牙的单、双根管发生率及根管形态走向进行分析,比较其在下颌中切牙双根管检出率方面的差异,为临床治疗提供依据.方法:收集新鲜拔除的下颌中切牙176颗,分别采用X线唇舌向摄片、肉眼下15#K型锉探查、根管显微镜下15#K型锉探查、螺旋CT扫描、离体牙横截面法进行观察.采用SAS6.12软件包对所得数据进行统计学分析,采用McNemar确切概率法对5种方法双根管检出率进行两两比较.结果:以离体牙横截面观察结果为金标准,176颗下颌中切牙的双根管率为9.66%,双根管均为唇舌向分根,其中Ⅱ型根管占4.55%,V型根管占5.11%.其他方法双根管检出率分别为X线唇舌向摄片法0.00%、肉眼下15#K型锉探查法2.84%、根管显微镜下15#K型锉探查法4.76%、螺旋CT扫描法9.09%.对5种不同方法的观察结果进行列联系数γ的统计学分析显示,在下颌中切牙双根管的检出率方面,离体牙横截面观察法>螺旋CT扫描法>根管显微镜下15#K型锉探查法>肉眼下15#K型锉探查法>X线唇舌向摄片法.结论:下颌中切牙存在一定比例的双根管发生率,临床医师应高度重视舌侧根管的存在,避免遗漏.当临床上常用的X线唇舌向摄片法和肉眼法不能发现可疑双根管时,建议改用X线偏移投照牙片法或使用根管显微镜及螺旋CT扫描等辅助检查方法.%PURPOSE: To investigate the detected rate and modality of multiple canals in mandibular central incisor by S different methods and to compare the results and differences among the methods, in order to provide give theoretical evidence of choosing right method and treatment in clinic. METHODS: 176 mandibular central incisors were examined by 5 different methods,ineluding radiograph at a horizontal angle of 0, macrography 15#K - file, dental operative microscope, spiral CT scanning, and dental cross section. All

  5. 上颌双侧中切牙外伤行冠延长术后的修复设计%Design of bilateral maxillary central incisor prosthesis after surgical crown lengthening

    Institute of Scientific and Technical Information of China (English)

    牛建杰; 杨帆

    2014-01-01

    目的:比较上颌双侧中切牙外伤行冠延长术后,不同修复设计对牙槽骨应力及牙齿动度的影响。方法:通过逆向工程技术建立齿冠延长术后不同骨下降高度的三维有限元模型,并将其设计为单冠、二联冠、三联冠、四联冠修复;然后用三维有限元法分析降低不同牙槽骨高度对桩核冠修复后牙槽骨应力分布及牙齿动度的影响。结果:随着牙槽骨高度的降低,所有修复形式组的牙槽骨应力及牙齿位移都有所上升,其中单冠修复组的增加幅度最大;当骨高度下降1 mm和2 mm时,单冠和3种联冠修复均能满足牙周潜力的要求;而骨下降高度为3 mm时,单冠修复组的应力值超过了牙周潜力的范围,二联冠修复接近牙周潜力,三联冠及四联冠修复均小于牙周潜力。结论:去骨高度在2 mm以内时,单冠和二联冠修复均可,但二联冠可以降低手术后造成的不利影响;当去骨高度为3 mm时,必须采用联冠修复,最好选用三联冠修复。%AIM:To investigate the effects of different prosthetic designs on the alveolar bone stress distri-bution and tooth moblilty of bilateral maxillary central incisors after surgical crown lengthening.METHODS:A three dimensional finite element model(3DFEM)of crowns with different alveolar bone height aroud the bilateral maxillary incisors was established by reverse modeling method.According to the design of prosthesis,the models was divided into 4 groups:single crown,2-unit combined crowns,3-unit combined crowns and 4-unit combined crowns.The alveolar bone stress distribution and terminal mobility with different crown design was analyzed using the 3DFEM.RESULTS:The maximum von Mises stress in the alveolar bone and the terminal mobility of the crown increased with the reduction of alveolar bone height.When the bone height reduced by less than 2 mm,all designs of restorations meet the require-ments of periodontal

  6. Orthodontic intrusion of maxillary incisors: a 3D finite element method study

    Directory of Open Access Journals (Sweden)

    Armando Yukio Saga

    2016-02-01

    Full Text Available Objective: In orthodontic treatment, intrusion movement of maxillary incisors is often necessary. Therefore, the objective of this investigation is to evaluate the initial distribution patterns and magnitude of compressive stress in the periodontal ligament (PDL in a simulation of orthodontic intrusion of maxillary incisors, considering the points of force application. Methods: Anatomic 3D models reconstructed from cone-beam computed tomography scans were used to simulate maxillary incisors intrusion loading. The points of force application selected were: centered between central incisors brackets (LOAD 1; bilaterally between the brackets of central and lateral incisors (LOAD 2; bilaterally distal to the brackets of lateral incisors (LOAD 3; bilaterally 7 mm distal to the center of brackets of lateral incisors (LOAD 4. Results and Conclusions: Stress concentrated at the PDL apex region, irrespective of the point of orthodontic force application. The four load models showed distinct contour plots and compressive stress values over the midsagittal reference line. The contour plots of central and lateral incisors were not similar in the same load model. LOAD 3 resulted in more balanced compressive stress distribution.

  7. Orthodontic intrusion of maxillary incisors: a 3D finite element method study

    Science.gov (United States)

    Saga, Armando Yukio; Maruo, Hiroshi; Argenta, Marco André; Maruo, Ivan Toshio; Tanaka, Orlando Motohiro

    2016-01-01

    Objective: In orthodontic treatment, intrusion movement of maxillary incisors is often necessary. Therefore, the objective of this investigation is to evaluate the initial distribution patterns and magnitude of compressive stress in the periodontal ligament (PDL) in a simulation of orthodontic intrusion of maxillary incisors, considering the points of force application. Methods: Anatomic 3D models reconstructed from cone-beam computed tomography scans were used to simulate maxillary incisors intrusion loading. The points of force application selected were: centered between central incisors brackets (LOAD 1); bilaterally between the brackets of central and lateral incisors (LOAD 2); bilaterally distal to the brackets of lateral incisors (LOAD 3); bilaterally 7 mm distal to the center of brackets of lateral incisors (LOAD 4). Results and Conclusions: Stress concentrated at the PDL apex region, irrespective of the point of orthodontic force application. The four load models showed distinct contour plots and compressive stress values over the midsagittal reference line. The contour plots of central and lateral incisors were not similar in the same load model. LOAD 3 resulted in more balanced compressive stress distribution. PMID:27007765

  8. Dual embryonic origin of maxillary lateral incisors: clinical implications in patients with cleft lip and palate

    Science.gov (United States)

    Garib, Daniela Gamba; Rosar, Julia Petruccelli; Sathler, Renata; Ozawa, Terumi Okada

    2015-01-01

    Introduction: Cleft lip and palate are craniofacial anomalies highly prevalent in the overall population. In oral clefts involving the alveolar ridge, variations of number, shape, size and position are observed in maxillary lateral incisors. The objective of this manuscript is to elucidate the embryonic origin of maxillary lateral incisors in order to understand the etiology of these variations. Contextualization: The hypothesis that orofacial clefts would split maxillary lateral incisor buds has been previously reported. However, recent studies showed that maxillary lateral incisors have dual embryonic origin, being partially formed by both the medial nasal process and the maxillary process. In other words, the mesial half of the lateral incisor seems to come from the medial nasal process while the distal half of the lateral incisor originates from the maxillary process. In cleft patients, these processes do not fuse, which results in different numerical and positional patterns for lateral incisors relating to the alveolar cleft. In addition to these considerations, this study proposes a nomenclature for maxillary lateral incisors in patients with cleft lip and palate, based on embryology and lateral incisors position in relation to the alveolar cleft. Conclusion: Embryological knowledge on the dual origin of maxillary lateral incisors and the use of a proper nomenclature for their numerical and positional variations renders appropriate communication among professionals and treatment planning easier, in addition to standardizing research analysis. PMID:26560830

  9. Dual embryonic origin of maxillary lateral incisors: clinical implications in patients with cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2015-10-01

    Full Text Available Introduction:Cleft lip and palate are craniofacial anomalies highly prevalent in the overall population. In oral clefts involving the alveolar ridge, variations of number, shape, size and position are observed in maxillary lateral incisors. The objective of this manuscript is to elucidate the embryonic origin of maxillary lateral incisors in order to understand the etiology of these variations.Contextualization: The hypothesis that orofacial clefts would split maxillary lateral incisor buds has been previously reported. However, recent studies showed that maxillary lateral incisors have dual embryonic origin, being partially formed by both the medial nasal process and the maxillary process. In other words, the mesial half of the lateral incisor seems to come from the medial nasal process while the distal half of the lateral incisor originates from the maxillary process. In cleft patients, these processes do not fuse, which results in different numerical and positional patterns for lateral incisors relating to the alveolar cleft. In addition to these considerations, this study proposes a nomenclature for maxillary lateral incisors in patients with cleft lip and palate, based on embryology and lateral incisors position in relation to the alveolar cleft.Conclusion:Embryological knowledge on the dual origin of maxillary lateral incisors and the use of a proper nomenclature for their numerical and positional variations renders appropriate communication among professionals and treatment planning easier, in addition to standardizing research analysis.

  10. Distribuição de tensões em modelo fotoelástico decorrente da intrusão dos incisivos inferiores por meio do arco base de Ricketts Stress distribution in a photoelastic model resulting from intrusion of mandibular incisors using Ricketts utility arch

    Directory of Open Access Journals (Sweden)

    Cristiane Aparecida de Assis Claro

    2011-10-01

    Full Text Available OBJETIVO: o presente estudo analisou a distribuição de tensões, em modelo fotoelástico, gerada por arco base de intrusão de incisivos inferiores. Compararam-se as tensões entre os terços radiculares de cada incisivo e, ainda, verificou-se a existência de diferenças de concentrações de tensões entre incisivos. MÉTODOS: foram confeccionados 15 arcos base de intrusão e a força de ativação foi mensurada em 50gf na região da linha média. O modelo fotoelástico foi observado em polariscópio circular, na configuração de campo escuro, e fotografado. As fotografias frontais foram analisadas e as ordens de franjas em cada região registradas. A análise de Kappa ponderado identificou a repetibilidade do método. A comparação entre as tensões foi realizada pelo teste de Kruskal-Wallis complementado com teste de Dunn com nível alfa de 5%. RESULTADOS E CONCLUSÕES: os resultados identificaram que as maiores magnitudes de tensões foram observadas nas regiões cervicais. Ao se comparar as ordens de franjas entre os dentes, as maiores magnitudes de tensões foram observadas nos incisivos centrais. Portanto, a região cervical pode estar mais sujeita a reabsorções, assim como os incisivos centrais, por concentrarem maiores tensões.OBJECTIVE: The present study is concerned with stress distribution in a photoelastic model, caused by lower incisor intrusion using utility arch. The stress levels on the radicular thirds of each lower incisors were compared and the stress concentration differences on each incisor were evaluated. METHODS: Fifteen intrusion utility arches were made up. The activation force of 50 gf was measured in the midline. The photoelastic model was observed using a circular polariscope in a dark field configuration, and, then, photographed. Frontal photographs were analyzed, and the fringe order in each region was registered. The method replicability was assessed by the Kappa weighted analysis. The comparison between

  11. Impacted permanent incisors associated with compound odontoma.

    Science.gov (United States)

    Machado, Cintia de Vasconcellos; Knop, Luégya Amorin Henriques; da Rocha, Maria Celina Barreiros Siquara; Telles, Paloma Dias da Silva

    2015-01-12

    Odontomas are the most common odontogenic tumours of the maxillary bones, characterised by a slow growth and benign behaviour. They are usually small, asymptomatic and diagnosed after routine radiographic examination. The aim of this study was to report a case of a compound odontoma in the anterior maxilla of a 7-year-old girl, which was causing the impaction of the maxillary right central and lateral incisors, as well as the prolonged retention of the corresponding primary teeth. We also aimed to review the literature about these tumours, since they are not part of the dentist's day-to-day clinical practice. The clinical and radiographic features, the diagnosis and treatment of the case were discussed in this work.

  12. 成年正畸患者下中切牙间出现黑三角的病因探讨%Etiology of open gingival embrasures between two mandibullary central incisors after orthodontic treatmeat in adults

    Institute of Scientific and Technical Information of China (English)

    商燕丽; 冯剑颖; 林新平; 谷志远

    2009-01-01

    目的 评价成年固定正畸患者在治疗后下颌中切牙之间出现黑三角的病因及它们之间的联系,为临床预防出现黑三角提供理论依据.方法 实验组为100例在正畸治疗后出现黑三角的成年患者,对照组为79例在正畸治疗后未出现黑三角的成年患者,均采用直丝弓矫正技术.治疗前、后两组都分别拍摄曲面断层片进行测量分析,采用spss11.5软件包进行统计学分析.结果 治疗前下颌中切牙的旋转和重叠交错与黑三角的发生没有统计学的意义.两个下颌中切牙近中釉牙骨质界点的距离、釉牙骨质界到邻接点的距离、牙槽嵴顶到釉牙骨质界的距离、下颌中切牙邻接点到牙齿长轴的距离等与黑三角的发生有关(P<0.05),有统计学意义.女性发生黑三角比例较高(P<0.05),有统计学意义.牙周情况方面,有牙结石的患者发生黑三角的比例高(P<0.05),有统计学意义.结论 成年正畸患者发生黑三角的概率与矫治前的牙齿牙周的某些因素和矫治过程中变化程度有显著的相关性.黑三角是一个多因素发病的疾病.%Objective To evaluate the etiology of posttreatmeat open gingival embrasures in adult orthodontic patients,examine the associations and a theoretical basis for clinical prevention of open gingival embrasures. Methods A subsample of 179 patients were i-dentified for measurement and divided into 2 groups:79 patients were normal gingival embrasures and 100 patients were open gingival embrasures(56 males,123 females;18 ~ 38 years of age). Digital images of the pretreatment mandibuUary models and posttreatment panoramic radiographs were made to measure the pretreatment and posttreatment variables. The data were analyzed using SPSS 11.5 software package. Results Pretreatment mandibullary central incisor rotation and overlap were not statistically associated with postt-reatmeat open gingival embrasures. A posttreatment CEJ-CEJ distance of the two

  13. Calcium hydroxide induced apical barrier in fractured nonvital immature permanent incisors

    Directory of Open Access Journals (Sweden)

    Vellore K

    2010-06-01

    Full Text Available Management of trauma to an immature permanent incisor is a challenge, especially when the pulp is necrotic. The aim of this study is to discuss the management of fractured maxillary right and left central incisors with immature root apex. Radiographic evaluation revealed that the tooth 11 had convergent apical walls, whereas tooth 21 had parallel apical walls; both the incisors were treated with pure calcium hydroxide paste to induce apical development. Follow-up clinical and radiographic examinations confirmed apical barrier at 3 months. Radiograph of tooth 11 with convergent roots showed continued apical development, whereas tooth 21 showed apical bridging, following which root canal was completed in both the teeth. Therefore, in view of the simplicity of this method, we believe that calcium hydroxide can be reemphasized as one of the treatment alternatives for fractured nonvital immature permanent incisors to induce apical barrier.

  14. Comparison of the physiological properties of human periodontal-masseteric reflex evoked by incisor and canine stimulation

    Directory of Open Access Journals (Sweden)

    Hiroko eOhmori

    2012-06-01

    Full Text Available Introduction: The present study was designed to clarify whether the bilateral cooperation in the human periodontal-masseteric reflex (PMR differs between central incisors and canines. Methods: Surface array electrodes were placed on the bilateral masseter muscles to simultaneously record the firing activities of single motor units from both sides in 7 healthy adults. During light clenching, mechanical stimulation was applied to the right maxillary central incisor and canine to evoke the PMR. Unitary activity was plotted with respect to the background activity and firing frequency. The slope of the regression line (sRL and the correlation coefficient (CC between the central incisor and canine and the lateral differences between these values were compared. Results: There were significant differences in the sRL and CC, as well as lateral differences, between the central incisor- and canine-driven PMR. Discussion: These results suggest that the PMR differs depending on both the tooth position and laterality.

  15. Incisor wear and age in Yellowstone bison

    Science.gov (United States)

    Christianson, D.A.; Gogan, P.J.P.; Podruzny, K.M.; Olexa, E.M.

    2005-01-01

    Biologists commonly use tooth eruption and wear patterns or cementum annuli techniques to estimate age of ungulates. However, in some situations the accuracy or sampling procedures of either approach are undesirable. We investigated the progression of several quantitative measures of wear with age, using permanent first incisors from Yellowstone bison (Bison bison), and tested for differences between sexes and herds. We further investigated the relationship of wear and age to explore an age-estimation method. Labial-lingual width (LLW) correlated best with assigned age (r2=0.66, males; r2=0.76 females). Labial-lingual width differed between sexes, with females showing ∼0.2 mm more wear than males. Additionally, differences in rate of wear existed between bison of the northern and central Yellowstone herds (1.2 and 0.9 mm/year, respectively). We developed a regression formula to test the power of LLW as an estimator of Yellowstone bison age. Our method provided estimated ages within 1 year of the assigned age 73% and 82% of the time for female and male bison, respectively.

  16. Construction of three-dimension al finite element model of maxillary central incisor with various crown-root ratio and labial alveolar bone width%建立不同临床冠根比和唇侧牙槽嵴顶厚度的上颌中切牙三维有限元模型

    Institute of Scientific and Technical Information of China (English)

    张艺君; 廖沐莹; 张翼

    2014-01-01

    Objective:to construct a three-dimensional finite element model of maxillary central incisor with various crown-root ratio and labial alveolar bone width.Methods:after thoroughly cleaning and polished, an extracted maxillary central incisor with normal anatomic structure was scanned with micro-CT technique, and its two dimensional images were transferred into a 3-D model by using the software Mimic, reverse engineering software Geomagic, computer aid design program UG6. The 3-D parametric model of a maxillary central incisor with various crown-root ratio, periodontal membrane and alveolar bone were established in the UG software through its automated modeling.Results:The 3D parametric model with precise anatomical features were successfully established. In the Design Exploration, the clinical crown-root ratio and width of labial alveolar bone were defined as input parameters with the former ranging from 1.1 to 2.5 and the later from 0.1mm to 0.5mm. Conclusion:the 3D parametric model of model of maxillary central incisor with various crown-root ratio and labial alveolar bone width was successfully established by reverse engineering software which had precise anatomical features.%目的:建立不同临床冠根比例和唇侧牙槽嵴顶厚度的上颌中切牙三维有限元模型。方法:选择一颗解剖形态标准的离体上颌中切牙清理抛光后,在显微CT扫描下获得断层二维图像,结合有限元软件Mimics、Geomagic及UG实现三维模型的实体化。利用UG软件构建出牙周膜、松质骨及皮质骨模块,建立上颌中切牙不同临床冠根比例及唇侧牙槽嵴顶厚度的自适应模型。结果:构建了不同临床冠根比例和唇侧牙槽嵴顶厚度的三维有限元模型。将变量冠根比例的变化范围设置为1.1-2.5,变量唇侧牙槽嵴顶厚度的变化范围设置为0.1mm-0.5mm。结论:采用有限元软件建立的不同临床冠根比例和牙槽嵴顶厚度的三维有限元模型,

  17. Clinical management of a fused mandibular lateral incisor with supernumerary tooth: A case report

    Directory of Open Access Journals (Sweden)

    Seda Aydemir

    2016-01-01

    Full Text Available The purpose of this report is to present a rare case of a fused mandibular lateral incisor with supernumerary tooth with a follow-up for 18-months. A 35-year-old female patient was referred to our clinic with an extraoral sinus tract in the chin. The intraoral diagnosis revealed the fusion of her mandibular lateral incisors. Vitality pulp tests were negative for mandibular right central and lateral incisors. Radiographic examinations showed a fused tooth with two separate pulp chambers, two distinct roots, and two separate root canals. There were also periapical lesion of fused teeth and mandibular right central incisor, so endodontic treatment was carried out the related teeth. Radiographic examination revealed a complete healing of the lesion postoperatively at the end of 18-months. This paper reports the successful endodontic and restorative treatment of unilateral fused incisors. Because of the abnormal morphology of the crown and the complexity of the root canal system in fused teeth, treatment protocols require special attention.

  18. Clinical management of a fused mandibular lateral incisor with supernumerary tooth: A case report

    Science.gov (United States)

    Aydemir, Seda; Ozel, Emre; Arukaslan, Goze; Tekce, Neslihan

    2016-01-01

    The purpose of this report is to present a rare case of a fused mandibular lateral incisor with supernumerary tooth with a follow-up for 18-months. A 35-year-old female patient was referred to our clinic with an extraoral sinus tract in the chin. The intraoral diagnosis revealed the fusion of her mandibular lateral incisors. Vitality pulp tests were negative for mandibular right central and lateral incisors. Radiographic examinations showed a fused tooth with two separate pulp chambers, two distinct roots, and two separate root canals. There were also periapical lesion of fused teeth and mandibular right central incisor, so endodontic treatment was carried out the related teeth. Radiographic examination revealed a complete healing of the lesion postoperatively at the end of 18-months. This paper reports the successful endodontic and restorative treatment of unilateral fused incisors. Because of the abnormal morphology of the crown and the complexity of the root canal system in fused teeth, treatment protocols require special attention. PMID:26962321

  19. Assessment of open and incomplete bite correction by incisor overlap and optical density of polyvinyl siloxane bite registration.

    Science.gov (United States)

    Shpack, Nir; Einy, Shmuel; Beni, Lea; Vardimon, Alexander D

    2006-04-01

    Open bite (OB) is a generalized term, which could incorporate subgroups that react differently to vertical correction. The objectives of the present study were to detect vertical treatment changes in incomplete bite (IB: inter-incisor overlap with no lower incisor contact with teeth or palate) and OB (no inter-incisor overlap) groups compared with a complete bite (CB: inter-incisor overlap with full lower incisor contact with teeth or palate) control group, to evaluate treatment response of the central and lateral incisors, and to study the vertico-sagittal interaction. Dental casts were taken at three time points, pre-treatment, post-treatment, and after one year of retention, from 54 Class II patients (22 males and 32 females with a mean age of 11 years 6 months) divided into three groups: CB (n = 21), IB (n = 18) and OB (n = 15). Measurements included incisor overlap (mm) and optical density (OD/mm2) of occlusal bite registration made of polyvinl siloxane. Both CB and IB groups demonstrated post-retention bite opening. However, bite opening in the CB group was three times greater than that in the IB group (e.g. lower lateral = -1.42 mm, 118 OD/mm2 versus -0.40 mm, 107 OD/mm2). Conversely, the OB group showed a significant (P < 0.001) bite closure (e.g. lower lateral = 1.30 mm, -377 OD/mm2). Overjet changes affected OD measurements, causing diversity in OD and millimetric measurements of the lateral incisors in the IB group. In conclusion, the OB group demonstrated a significant stable vertical correction; a post-treatment non-contact inter-incisor relationship was determined by a vertico-sagittal relapse; and full compensation of an IB was not possible.

  20. Immediate post-traumatic upper incisor reconstruction using composite resin materials.

    Science.gov (United States)

    Panduric, Vlatko; Gabric, Dragana; Negovetic-Mandic, Visnja

    2008-02-01

    Single visit reconstruction of the fractured crown can be completed with composite resins if there is no bleeding due to the soft tissue injury. Clinical inspection revealed a complex crown fracture of the central incisor as well as a simple horizontal fracture of the lateral incisor crown of the enamel-dentin type. Vertical fracture separated the palatal enamel wall from the rest of the lateral incisor crown. After the completion of the endodontic sanitation, root canals were prepared for prefabricated composite posts and crown reconstructions were performed with the Finger Tip Technique by using composite resin materials. The advantage of this kind of reconstruction is preservation of the hard dental crown tissue removed in case of prosthetic therapy, especially in younger patients. Reconstruction can be finished in one visit, without the need for a dental technician and laboratory.

  1. Finite element analysis of the maxillary central incisor with crown lengthening surgery and post-core restoration in management of crown-root fracture%上颌中切牙冠根折行冠延长术并桩核冠修复的三维有限元分析

    Institute of Scientific and Technical Information of China (English)

    甄敏; 胡文杰; 荣起国

    2015-01-01

    Objective:To construct the finite element models of maxillary central incisor and the simu-lations with crown lengthening surgery and post-core restoration in management of different crown-root fracture types, to investigate the stress intensity and distributions of these models mentioned above, and to analyze the indications of crown lengthening from the point of view of mechanics. Methods:An extrac-ted maxillary central incisor and alveolar bone plaster model were scanned by Micro-CT and dental impression scanner ( 3shape D700 ) respectively. Then the 3D finite element models of the maxillary central incisor and 9 simulations with crown lengthening surgery and post-core restoration were construc-ted by Mimics 10. 0, Geomagic studio 9. 0 and ANSYS 14. 0 software. The oblique static force (100 N) was applied to the palatal surface ( the junctional area of the incisal 1/3 and middle 1/3 ) , at 45 degrees to the longitudinal axis, then the von Mises stress of dentin, periodontal ligament, alveolar bone, post and core, as well as the periodontal ligament area, were calculated. Results:A total of 10 high-precision three-dimensional finite element models of maxillary central incisor were established. The von Mises stress of models: post >dentin >alveolar bone >core >periodontal ligament, and the von Mises stress increased linearly with the augmentation of fracture degree ( besides the core) . The periodontal ligament area of the crown lengthening was reduced by 12% to 33%. The von Mises stress of periodontal ligament of the B2L2c, B2L3c, B3L1c, B3L2c, B3L3c models exceeded their threshold limit value, respective-ly. Conclusion: The maxillary central incisors with the labial fracture greater than three-quarter crown length and the palatal fracture deeper than 1 mm below the alveolar crest are not the ideal indications of the crown lengthening surgery.%目的:构建上颌中切牙及其不同冠根折类型牙冠延长术后桩核冠修复的三维有限元模型,研究

  2. [Upper lateral incisor with 2 canals].

    Science.gov (United States)

    Fabra Campos, H

    1991-01-01

    Clinical case summary of the patient with an upper lateral incisor with two root canals. The suspicion that there might be an anatomic anomaly in the root that includes a complex root canal system was made when an advanced radicular groove was detected in the lingual surface or an excessively enlarged cingulum. PMID:1659854

  3. [Upper lateral incisor with 2 canals].

    Science.gov (United States)

    Fabra Campos, H

    1991-01-01

    Clinical case summary of the patient with an upper lateral incisor with two root canals. The suspicion that there might be an anatomic anomaly in the root that includes a complex root canal system was made when an advanced radicular groove was detected in the lingual surface or an excessively enlarged cingulum.

  4. The distribution of magnesium in developing rat incisor dentin

    International Nuclear Information System (INIS)

    Previous studies have shown that rat incisor dentin contains a considerable amount of magnesium that is distributed heterogeneously. The cementum-related dentin, especially its incisal portion, is richest in magnesium. It was the purpose of the present study to investigate the changes that occur in the magnesium content during dentin maturation. Cross-sections were prepared from rat incisors at the apical, middle, and incisal levels. By means of an electron microprobe, tracings were made of the Ca-, Mg-, and P- signal frequencies. Comparison of corresponding dentin layers within and between the cross-sections showed that the Mg/P molar ratio was always higher in the cementum-related dentin (CRD) than in the enamel-related dentin (ERD) and increased from the apex toward the incisal edge. Especially in the incisal cross-section, an increase in Mg/P was found from the older (peripheral) toward the younger (central) dentin layers. As the Mg/P ratio varied from 0.07 to 0.33, the Ca/P ratio was found to fluctuate from 1.48 to 1.15. The two ratios appeared to be highly correlated (r = -0.97; p less than 0.001), suggesting that Mg replaces Ca and is bound to phosphate

  5. Forces that fracture teeth during extraction with mandibular premolar and maxillary incisor forceps.

    Science.gov (United States)

    Ahel, V; Ćabov, T; Špalj, S; Perić, B; Jelušić, D; Dmitrašinović, M

    2015-12-01

    Our aim was to measure the forces that fracture teeth during extraction based on the effectiveness of the extraction forceps, and to compare them with data collected about forces applied to extracted teeth that did not fracture. We studied 208 patients whose teeth fractured during both the standard and our new method of extraction: maxillary incisors (n=79) extracted with forceps 1 (maxillary incisor forceps), and both maxillary (n=95) and mandibular incisors (n=34) extracted with forceps 13 (mandibular premolar forceps). Forces needed to fracture were assessed with a specially-designed instrument for measuring pressure and rotation. Mean (SD) pressure at the fracture site was significantly higher in maxillary incisors extracted with forceps 1 (1.26 (0.26) bar) then in both maxillary and mandibular incisors extracted with forceps 13 (0.96 (0.19) and 0.98 (0.16), pforces that break teeth during extractions are sometimes only slightly higher than the extraction forces, so caution is needed during extraction.

  6. Reattachment of fractured teeth fragments in mandibular incisors: a case report.

    Science.gov (United States)

    Yousef, Mohammed K

    2015-01-01

    The majority of dental trauma involves anterior teeth, especially the maxillary central incisors. A mandibular incisor fracture with or without pulp tissue involvement is considerably less common. Different approaches for treating these fractured teeth have been reported in the literature. The type of treatment rendered depends mainly on the extent of fracture, pulp involvement, radicular fracture, biologic width infringement or violation, and presence of the fractured piece. This case report illustrates reattachment of fractured fragments on two mandibular incisors without pulp exposure using a new proposed reattachment method using a combination of two different types of composite materials together with an orthodontic lingual retention wire. An 8-year-old female patient presented with fractured mandibular left incisors (Ellis class II fracture). Broken pieces were saved and brought in a closed container in water. Periapical radiographs revealed no evidence of pulpal involvement in either tooth and no periapical radiolucency was noticed. Fractured fragments and the broken teeth were prepared with circumferential bevels. Reattachment of the fractured fragments were done using two types of composite resin materials and a lingual orthodontic retention wire was also used. The patient was recalled after 8 months to follow up both teeth. Clinical examination revealed excellent composite restorations covering the fracture lines.

  7. Reattachment of fractured teeth fragments in mandibular incisors: a case report

    Directory of Open Access Journals (Sweden)

    Yousef MK

    2015-04-01

    Full Text Available Mohammed K YousefDepartment of Operative Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi ArabiaAbstract: The majority of dental trauma involves anterior teeth, especially the maxillary central incisors. A mandibular incisor fracture with or without pulp tissue involvement is considerably less common. Different approaches for treating these fractured teeth have been reported in the literature. The type of treatment rendered depends mainly on the extent of fracture, pulp involvement, radicular fracture, biologic width infringement or violation, and presence of the fractured piece. This case report illustrates reattachment of fractured fragments on two mandibular incisors without pulp exposure using a new proposed reattachment method using a combination of two different types of composite materials together with an orthodontic lingual retention wire. An 8-year-old female patient presented with fractured mandibular left incisors (Ellis class II fracture. Broken pieces were saved and brought in a closed container in water. Periapical radiographs revealed no evidence of pulpal involvement in either tooth and no periapical radiolucency was noticed. Fractured fragments and the broken teeth were prepared with circumferential bevels. Reattachment of the fractured fragments were done using two types of composite resin materials and a lingual orthodontic retention wire was also used. The patient was recalled after 8 months to follow up both teeth. Clinical examination revealed excellent composite restorations covering the fracture lines.Keywords: reattachment, fractured teeth, dental trauma 

  8. Refining Approximating Betweenness Centrality Based on Samplings

    CERN Document Server

    Ji, Shiyu

    2016-01-01

    Betweenness Centrality (BC) is an important measure used widely in complex network analysis, such as social network, web page search, etc. Computing the exact BC values is highly time consuming. Currently the fastest exact BC determining algorithm is given by Brandes, taking $O(nm)$ time for unweighted graphs and $O(nm+n^2\\log n)$ time for weighted graphs, where $n$ is the number of vertices and $m$ is the number of edges in the graph. Due to the extreme difficulty of reducing the time complexity of exact BC determining problem, many researchers have considered the possibility of any satisfactory BC approximation algorithms, especially those based on samplings. Bader et al. give the currently best BC approximation algorithm, with a high probability to successfully estimate the BC of one vertex within a factor of $1/\\varepsilon$ using $\\varepsilon t$ samples, where $t$ is the ratio between $n^2$ and the BC value of the vertex. However, some of the algorithmic parameters in Bader's work are not yet tightly boun...

  9. 纤维桩长度和牙槽骨高度对上颌中切牙抗折性能的影响%Effect of alveolar bone height and fiber post length on the fracture resistance of endodontically treated maxillary central incisors

    Institute of Scientific and Technical Information of China (English)

    李晓杰; 胡书海; 任翔; 左恩俊

    2014-01-01

    背景:纤维桩具有与天然牙本质接近的弹性模量,在受外力时能够与根管壁保持广泛面接触,与牙本质形成一同质的整体,使应力沿根管壁均匀传导,减少根折的发生。  目的:观察牙槽骨高度和纤维桩长度对上颌中切牙抗折性能的影响。  方法:将48颗离体上颌中切牙随机分为6组,每组8颗。A,B,C组牙槽骨距离釉质牙骨质界的距离为2 mm,纤维桩长度分别为5,7,9 mm;D,E,F组牙槽骨距离釉质牙骨质界的距离为5 mm,纤维桩长度分别为5,7,9 mm。截冠、根管治疗、纤维桩树脂核及铸造金属全冠修复后,将试样牙置于电子万能试验机上,与牙体长轴呈45˚的加载方向,以1 mm/min的加载速度,持续加载至试样牙发生折裂。记录折裂时的加载强度和折裂模式。  结果与结论:牙槽骨高度对试样牙的抗折性能有显著影响(F=560.943,P0.05)。牙槽骨高度正常各组试样牙断裂模式多为可修复性断裂模式,牙槽骨高度降低各组试样牙断裂模式多为不可修复性断裂模式,差异有显著性意义(χ2=5.689,P OBJECTIVE:To investigate the effect of alveolar bone height and fiber post length on the fracture resistance of endodontical y treated maxil ary central incisors. METHODS:Forty-eight human maxil ary central incisors were assigned randomly to six groups (n=8) of three different post insertion depths (5, 7, 9 mm) and two alveolar bone levels (2 and 5 mm) from the cement-enamel junction. Al of them were restored by glass fiber posts with composite resin core and cast metal crown. The samples were loaded in a testing machine with a crosshead speed of 1 mm/min at a 45° angle to the long axis of the tooth on the palatal surfaces until tooth fracture occurred. The maximum load and failure mode were recorded. RESULTS AND CONCLUSION:Alveolar bone height had a significant influence on the fracture resistance (F

  10. Compound odontoma associated with impacted maxillary incisors

    Directory of Open Access Journals (Sweden)

    S Sreedharan

    2012-01-01

    Full Text Available Odontomas are considered to be the most common odontogenic tumors of the oral cavity. Some authors consider it as malformations rather than true neoplasms. The exact etiology of odontomes is still not known. Most odontomes are asymptomatic and are discovered during routine radiographic investigations. Odontomes generally cause disturbances in the eruption of the teeth, most commonly delayed eruption or deflection. The present report describes the surgical management of a case of compound odontoma in a 10-year-old boy who presented with a complaint of swelling in the maxillary right anterior region and retained deciduous incisors. The related literature is also being reviewed in this article.

  11. Compound odontoma associated with impacted maxillary incisors.

    Science.gov (United States)

    Sreedharan, S; Krishnan, I S

    2012-01-01

    Odontomas are considered to be the most common odontogenic tumors of the oral cavity. Some authors consider it as malformations rather than true neoplasms. The exact etiology of odontomes is still not known. Most odontomes are asymptomatic and are discovered during routine radiographic investigations. Odontomes generally cause disturbances in the eruption of the teeth, most commonly delayed eruption or deflection. The present report describes the surgical management of a case of compound odontoma in a 10-year-old boy who presented with a complaint of swelling in the maxillary right anterior region and retained deciduous incisors. The related literature is also being reviewed in this article.

  12. Molar incisor hypomineralisation: clinical management of the young patient.

    LENUS (Irish Health Repository)

    Daly, Dympna

    2009-04-01

    Molar incisor hypomineralisation (MIH) is a common developmental condition resulting in enamel defects in first permanent molars and permanent incisors. It presents at eruption of these teeth. Early diagnosis is essential since rapid breakdown of tooth structure may occur, giving rise to acute symptoms and complicated treatment. The purpose of this article is to review MIH and illustrate its clinical management in young children.

  13. Restoration of decayed primary incisors using strip crowns.

    Science.gov (United States)

    Pollard, M A; Curzon, J A; Fenlon, W L

    1991-05-01

    Caries of the primary incisors is a common problem that can be arrested if recognized early enough. However, the arrested decay is unsightly. Celluloid 'strip' crown forms, used with composite resin, now allow the restoration of even the most badly decayed primary incisors. The authors describe this quick and efficient technique. PMID:1884866

  14. [Behavior of the periodontium during leveling of the mandibular incisors: what precautions are needed?].

    Science.gov (United States)

    Castelli, Alicia; Le Gall, Michel; Monnet-Corti, Virginie

    2016-03-01

    Since the position of the mandibular incisors is one of the keys to successful treatment, most orthodontic treatments focus on control but take no special precautions regarding the periodontal environment. Can we trust the lateral headfilm alone when evaluating such slender quantities of bone surrounding the mandibular incisors? What is the true bone situation prior to treatment and above all, following alignment, leveling and uprighting of the incisors? We performed a prospective 3-year study on 50 patients to assess the periodontal behavior of the mandibular incisors following a leveling phase by means of a clinical approach using periodontal and radiologic probing based on measurements of bone thickness obtained by cone beam. The bone loss observed was not inconsiderable given the thinness of the initial bone. In the face of this clinical situation, we need to adapt our treatment by performing a pre-orthodontic periodontal check-up and by supplementing the diagnosis with 3D examinations for at-risk patients and by checking the incisal axes during the leveling phase. The advent of cone beam has provided us with a valuable tool making it possible to individualize orthodontic treatment and view the posttreatment bone environment and root positions. PMID:27083231

  15. Cone beam-computed topographic evaluation of a central incisor with an open apex and a failed root canal treatment using one-step apexification with Biodentine™: A case report.

    Science.gov (United States)

    Sinha, Nidhi; Singh, Bijay; Patil, Santosh

    2014-05-01

    A symptomatic endodontically treated immature tooth with periapical pathology presents multiple challenges to the clinician. Owing to incomplete root formation, gutta percha removal has to be done carefully without further damaging the periapical tissue or pushing the obturating material beyond the apex. Nonsurgical approach toward treating such a tooth would necessitate the creation of an apical barrier followed by conventional root canal treatment. Current literature suggests one-step apexification with mineral trioxide aggregate (MTA), with an apical matrix as the treatment of choice. A new calcium silicate-based cement also called as dentine substitute by the manufacturers with good handling properties has been introduced recently by the trade name Biodentine™ (Septodont, St. Maurdes Fossés, France). This case report presents management of a secondary endodontic case with an open apex treated with the concept of 'lesion sterilization and tissue repair (LSTR)' using triantibiotic paste and Biodentine™ for apical barrier formation. A 12-month follow up with cone beam-computed topography (CBCT) exhibited progressive involution of periapical radiolucency with indications of good healing of the periapical tissues and absence of clinical symptoms.

  16. Lower incisor retraction with a modified corticotomy.

    Science.gov (United States)

    Germeç, Derya; Giray, Bahadir; Kocadereli, Ilken; Enacar, Ayhan

    2006-09-01

    This case report demonstrates the orthodontic treatment facilitated with a new conservative corticotomy technique to shorten the treatment time during lower incisor retraction. The patient was a 22-year-old woman with protrusive profile, severe anterior crowding, an anterior crossbite, and Class III dental relationship. Orthodontic treatment consisted of the extraction of four first premolars with maximum anchorage. A modified corticotomy technique, in which the lingual vertical and subapical horizontal cuts were eliminated, was combined with orthodontic therapy for the retraction of the lower anterior teeth. Corticotomy-facilitated orthodontics dramatically reduced the treatment time without any adverse effects on the periodontium and the vitality of the teeth. The main advantages of this modified corticotomy technique were the elimination of the lingual cuts and flap, the reduction of surgery time, and minimum discomfort to the patient. At the end of active orthodontic therapy, balanced occlusion and facial esthetics were achieved. PMID:17029527

  17. Double Pyramidal Central Configurations with a Concave Quadrilateral Base

    Institute of Scientific and Technical Information of China (English)

    LIUXuefei

    2002-01-01

    As for a doudle pyramidal central configuration in 6-body problems,the case when its bese is a concave polygon is studied.By advancing several assumptions according to the definition of double pyramidal central configuration and deducing two theorems and two corollaries on this subject,the essential and sufficient conditions to form a double pyramidal central configuration with a concave quadriateral base are demonstrated.

  18. Successful Conservative Endodontic Treatment of Fused Maxillary Incisors: A Case Report

    Directory of Open Access Journals (Sweden)

    Mesgarani A.

    2012-06-01

    Full Text Available Fusion is a rare developmental dental anomaly and its definitive diagnosis is of great importance for successful endodontic treatment.A twenty-five-year old female attended the Endodontic Department with the chief complaint about dysmorphic right front tooth and a history of vague pain since the previous 11 months, which had ceased during last one month. Oral cavity examination was performed, endodontic oriented sensitivity tests including cold, hot, and electric pulp tests were conducted, and periapical radiography was also ordered.Oral cavity examination revealed an enlarged permanent right maxillary incisor with deep caries on the lingual surface. All vitality tests were negative. Examinations were normal except for one missing tooth in the total count in the upper right quadrant. Periapical radiography clarified a fused maxillary central and adjacent lateral incisor with large coronal radiolucency involving the pulp and a periapical radiolucent area suggestive of a chronic apical periodontitis. The final diagnosis was established as fused maxillary incisors with necrosis and chronic apical periodontitis. A conservative non-surgical root canal therapy was planned and careful negotiation and obturation were performed after obtaining the informed consent, followed by the esthetic reconstruction. A six month follow-up revealed that periapical radiolucency had almost disappeared, the teeth were in function, and the patient reported no complaint.

  19. Central Tracking Detector Based on Scintillating Fibres

    CERN Multimedia

    2002-01-01

    Scintillating fibres form a reasonable compromise for central tracking detectors in terms of price, resolution, response time, occupancy and heat production. \\\\ \\\\ New fluorescents with large Stokes shifts have been produced, capable of working without wavelength shifters. Coherent multibundles have been developed to achieve high packing fractions. Small segments of tracker shell have been assembled and beam tests have confirmed expectations on spatial resolution. An opto-electronic delay line has been designed to delay the track patterns and enable coincidences with a first level trigger. Replacement of the conventional phosphor screen anode with a Si pixel chip is achieved. This tube is called ISPA-tube and has already been operated in beam tests with a scintillating fibres tracker. \\\\ \\\\ The aim of the proposal is to improve hit densities for small diameter fibres by increasing the fraction of trapped light, by reducing absorption and reflection losses, by reflecting light at the free fibre end, and by inc...

  20. Upper incisor to Soft Tissue Plane (UI-STP): a new reference for diagnosis and planning in dentofacial deformities.

    Science.gov (United States)

    Hernandez-Alfaro, Federico

    2010-09-01

    Planning in orthognathic surgery has been and still is an open issue. We have evolved from 2D classical cephalometric hard-tissue planning to 2D soft tissue planning, and finally to 3D and hard and soft tissue evaluation. This, to our knowledge, is the first description of a new Soft Tissue Plane (STP) and its relationship with the anterior position of the upper incisor (UI). Profile photographs of 110 "attractive individuals" with lips at rest or smiling and with upper incisor shown were used. The photographs used were of 65 professional models from two international agencies and 45 individuals considered most attractive in the internet forums, which included catwalk models and actors. In 86 cases (78.18 %), the incisor was located in front of the STP (A). In 15 cases (13.63%), it was on the plane (N); and in the remaining 9 cases (8.18%), it was behind (P). Despite the limitations of this study and based on our series, we can conclude that the upper incisor is located at or in front of the Soft Tissue Plane (STP) in 91.81% of the attractive facial profiles studied. On the other hand, the relative position of the upper incisor to the soft tissue plane (UI-STP) could be a useful diagnostic and planning tool in orthodontic and surgical management of dentofacial deformities.

  1. Upper incisor to Soft Tissue Plane (UI-STP): a new reference for diagnosis and planning in dentofacial deformities.

    Science.gov (United States)

    Hernandez-Alfaro, Federico

    2010-09-01

    Planning in orthognathic surgery has been and still is an open issue. We have evolved from 2D classical cephalometric hard-tissue planning to 2D soft tissue planning, and finally to 3D and hard and soft tissue evaluation. This, to our knowledge, is the first description of a new Soft Tissue Plane (STP) and its relationship with the anterior position of the upper incisor (UI). Profile photographs of 110 "attractive individuals" with lips at rest or smiling and with upper incisor shown were used. The photographs used were of 65 professional models from two international agencies and 45 individuals considered most attractive in the internet forums, which included catwalk models and actors. In 86 cases (78.18 %), the incisor was located in front of the STP (A). In 15 cases (13.63%), it was on the plane (N); and in the remaining 9 cases (8.18%), it was behind (P). Despite the limitations of this study and based on our series, we can conclude that the upper incisor is located at or in front of the Soft Tissue Plane (STP) in 91.81% of the attractive facial profiles studied. On the other hand, the relative position of the upper incisor to the soft tissue plane (UI-STP) could be a useful diagnostic and planning tool in orthodontic and surgical management of dentofacial deformities. PMID:20383095

  2. [Failure in anterior rehabilitation of agenesic maxillary lateral incisors].

    Science.gov (United States)

    Le Gall, Michel; Philippart-Rochaix, Martine; Philip-Alliez, Camille

    2016-03-01

    Agenesis of the maxillary lateral incisors poses particular problems for dentists, orthodontists and patients. Treatment of these ageneses is still highly controversial, both functionally and esthetically. The patient's smile and anterior guidance are affected and must be restored. The diagnosis is easy. Few mistakes are possible. However, managing patients with missing maxillary lateral incisors can be a challenge, commonly involving two possible treatment approaches: space opening to replace the missing lateral incisor with a prosthetic unit (denture, bridge or implant) or orthodontic space closure replacing the missing lateral incisor with the maxillary canine camouflaged to mimic the appearance of a lateral incisor. One of these two options will be adopted using multiple means...liable to trigger a multitude of possible errors. Ultimately, optimal results can only be achieved if there is excellent coordination between different practitioners in various specialties. Each clinician will have a specific role to play. Also, the patient and family are at the heart of the decision-making process, by virtue of their consent (treatment duration, financial resources) and their motivation. This multi-factorial, multi-disciplinary decision process means that treatment of the lateral incisor is an ongoing challenge for the clinician striving for the best possible result. Each case is different. No set rules exist. No single factor can be neglected if we are to avoid "failure". PMID:27083223

  3. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha

    OpenAIRE

    Mothé, Dimila; Ferretti, Marco P.; Avilla, Leonardo S.

    2016-01-01

    The incisors of proboscideans (tusks and tushes) are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres), the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition). The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglect...

  4. Replantation after extended dry storage of avulsed permanent incisors: report of a case.

    Science.gov (United States)

    Cobankara, Funda Kont; Ungor, Mete

    2007-08-01

    A 15-year-old boy lost his maxillary right and left central incisor teeth in a bicycle accident. He was referred to our clinic 1 week after the injury. The crown-root integrities of both the teeth were not damaged. Although the teeth were stored under dry conditions for 1 week, reimplantation of the teeth was planned to retain the teeth in the mouth for as long a period as possible because of the patient's age. Following the debridement and sterilization of root surfaces in 2.5% NaOCl, root canals were prepared and filled with calcium hydroxide. Then, about 2 mm of the apexes were resected to ensure that the roots easily seated in the alveolar socket and the prepared cavities in root ends were obturated with the amalgam. The teeth were placed into their respective sockets and splinted temporarily. The root canal therapy was completed 5 weeks later. Ankylosis was observed radiographically after 10 months. The patient is now 23 years old and he is still able to use both the central incisors functionally. However, there is a pink appearance on the cervical buccal surface of left central incisor because of progressive replacement resorption. In this case, the new treatment plan is to perform a permanent restoration with dental implants following the extraction of both teeth. Even though the long-term prognosis is uncertain, this treatment technique has provided an advantage for the patient in his adolescent period by maintaining the height of alveolar bone and making the provision of an aesthetically acceptable permanent restoration at a later age possible.

  5. The Grooved Rodent Incisor Recapitulates Rudimentary Teeth Characteristics of Ancestral Mammals.

    Science.gov (United States)

    Li, L; Tang, Q; Jung, H-S

    2016-07-01

    It is known from the paleontology studies of eutherian mammals that incisor numbers were reduced during evolution. The evolutionary lost incisors may remain as vestigial structures at embryonic stages. The recapitulation of the incisor patterns among mammalian species will potentially uncover the mechanisms underlying the phenotypic transition of incisors during evolution. Here, we showed that a minute tooth formed in the presumptive groove region of the gerbil upper incisor at the early developmental stages, during which multiple epithelial swellings and Shh transcription domains spatiotemporally appeared in the dental epithelium, suggests the existence of vestigial dental primordia. Interestingly, when we trimmed the surrounding mesenchyme from incisor tooth germs at or before the bud stage prior to ex vivo culture, the explants developed different incisor phenotypes ranging from triplicated incisors, duplicated incisors, to Lagomorpha-like incisors, corresponding to the incisor patterns in the eutherian mammals. These results imply that the phenotypic transition of incisors during evolution, as well as the achievement of ultimate incisors in adults, arose from differential integrations of primordia. However, when the incisor tooth germ was trimmed at the cap stage, a grooved incisor developed similar to the normal condition. Furthermore, the incisor tooth germ developed a small but smooth incisor after the additional removal of the minute tooth and a lateral rudiment. These results suggest that multiple dental primordia integrated before the cap stage, with the labial primordia contributing to the labial face of the functional incisor. The minute tooth that occupied the boundary of the 2 labial primordia might be implicated in the groove formation. This study sheds light on how rudiments incorporate into functional organs and aids the understanding of incisor evolution. PMID:26912224

  6. Eigenvector-Based Centrality Measures for Temporal Networks

    CERN Document Server

    Taylor, Dane; Clauset, Aaron; Porter, Mason A; Mucha, Peter J

    2015-01-01

    In the study of static networks, numerous "centrality" measures have been developed to quantify the importances of nodes in networks, and one can express many of these measures in terms of the leading eigenvector of a matrix. With the increasing availability of network data that changes in time, it is important to extend eigenvector-based centrality measures to time-dependent networks. In this paper, we introduce a principled generalization that is valid for any eigenvector-based centrality measure in terms of matrices of size $NT\\times NT$, where the components of the dominant eigenvector of such a matrix describes the centralities of $N$ nodes during $T$ time layers. Our approach relies on coupling centrality values between neighboring time layers with a inter-layer edge, whose weight controls the extent to which centrality trajectories change over time. By studying the limit of strong coupling between layers, we derive expressions for "time-averaged centralities," which are given by the zeroth-order terms ...

  7. Establishment of crown-root domain borders in mouse incisor.

    Science.gov (United States)

    Juuri, Emma; Saito, Kan; Lefebvre, Sylvie; Michon, Frederic

    2013-10-01

    Teeth are composed of two domains, the enamel-covered crown and the enamel-free root. The understanding of the initiation and regulation of crown and root domain formation is important for the development of bioengineered teeth. In most teeth the crown develops before the root, and erupts to the oral cavity whereas the root anchors the tooth to the jawbone. However, in the continuously growing mouse incisor the crown and root domains form simultaneously, the crown domain forming the labial and the root domain the lingual part of the tooth. While the crown-root border on the incisor distal side supports the distal enamel extent, reflecting an evolutionary diet adaptation, on the incisor mesial side the root-like surface is necessary for the attachment of the interdental ligament between the two incisors. Therefore, the mouse incisor exhibits a functional distal-mesial asymmetry. Here, we used the mouse incisor as a model to understand the mechanisms involved in the crown-root border formation. We analyzed the cellular origins and gene expression patterns leading to the development of the mesial and distal crown-root borders. We discovered that Barx2, En1, Wnt11, and Runx3 were exclusively expressed on the mesial crown-root border. In addition, the distal border of the crown-root domain might be established by cells from a different origin and by an early Follistatin expression, factor known to be involved in the root domain formation. The use of different mechanisms to establish domain borders gives indications of the incisor functional asymmetry.

  8. Central skull base lymphoma in children: MR and CT features

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hei-Kyung [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea); Cheon, Jung-Eun; Kim, In-One; Youn, Byung Jae; Jung, Ah Young; Shin, Su-Mi; Kim, Woo Sun; Yeon, Kyung Mo [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea); Seoul National University Hospital, Institute of Radiation Medicine, SNUMRC (Seoul National University Medical Research Center), Seoul (Korea)

    2008-08-15

    Central skull base tumours are rare in children. To characterize the imaging features of central skull base lymphoma in children to aid its diagnosis. The authors reviewed the CT findings (available in three patients) and MR findings (available in four patients) in four patients (three boys, one girl; age 2-12 years) with pathologically proven lymphoma (two with Burkitt lymphoma, two with B-cell lymphoma) involving the central skull base. Tumour location and extent, MRI signal intensities, noncontrast CT attenuation, patterns of enhancement, and changes in adjacent structures were evaluated. All four tumours involved the sphenoid bone. In three patients, the tumour extended to the ethmoid sinus and both cavernous sinuses. All lesions were isointense solid masses on T2-weighted images and showed avid enhancement, except for one lesion with a focal necrosis. All tumours were associated with adjacent dural thickening. Non-contrast CT showed highly attenuating masses and permeative bone destruction in the central skull base. Lymphoma involving the central skull base in children is visualized as an isointense mass on T2-weighted MRI with marked contrast enhancement and adjacent dural thickening, and as a highly attenuating mass on noncontrast CT with permeative or erosive bone destruction patterns. (orig.)

  9. Agreement in the diagnosis of dental fluorosis in central incisors performed by a standardized photographic method and clinical examination Concordância no diagnóstico da fluorose dentária em incisivos centrais realizado por um método fotográfico padronizado e pelo exame clínico

    Directory of Open Access Journals (Sweden)

    Carolina Castro Martins

    2009-05-01

    Full Text Available The aim of this study was to assess agreement in the diagnosis of dental fluorosis performed by a standardized digital photographic method and a clinical examination (gold standard. 49 children (aged 7-9 years were clinically evaluated by a trained examiner for the assessment of dental fluorosis. Central incisors were evaluated for the presence or absence of dental fluorosis and were photographed with a digital camera. Photographs were presented to three pediatric dentists, who examined the images. Data were analyzed using Cohen's kappa and validity values. Agreement in the diagnosis performed by the photographic method and clinical examination was good (0.67 and accuracy was 83.7%. The prevalence of dental fluorosis was reported to be higher in the clinical examination (49% compared with the photographic method (36.7%. The photographic method presented higher specificity (96% than sensitivity (70.8%, a positive predictive value (PPV of 94.4% and a negative predictive value (NPV of 77.4%. The diagnosis of dental fluorosis performed using the photographic method presented high specificity and PPV, which indicates that the method is reproducible and reliable for recording dental fluorosis.O objetivo do estudo foi comparar o diagnóstico de fluorose dentária realizado por um método fotográfico com o exame clínico (padrão ouro. Quarenta e nove crianças, de 7 e 9 anos, foram clinicamente examinadas por um examinador calibrado para fluorose dentária. Os incisivos foram fotografados com câmera digital e as fotografias foram apresentadas a três odontopediatras, que examinaram as imagens. A concordância por kappa entre o método fotográfico e o padrão ouro foi boa (0,67 e a acurácia foi de 83,67%. A prevalência de fluorose dentária foi levemente maior pelo método clínico (49% do que pelo fotográfico (36,7%. O método fotográfico apresentou maior especificidade (96% que sensibilidade (70,83%, valor de predição positivo (VPP de 94

  10. Orthodontic Treatment of a Mandibular Incisor Extraction Case with Invisalign

    Directory of Open Access Journals (Sweden)

    Khalid H. Zawawi

    2014-01-01

    Full Text Available Mandibular incisor extraction for orthodontic treatment is considered an unusual treatment option because of the limited number of patients that meet the criteria for such treatment. Accurate diagnosis and treatment planning is essential to achieve the desired results. Adult orthodontic patients are increasingly motivated by esthetic considerations and reject the idea of conventional fixed appliances. In recent years, Invisalign appliances have gained tremendous attention for orthodontic treatment of adult patients to meet their esthetic demands. In this case report, a case of Class I malocclusion was treated with mandibular incisor extraction using the Invisalign appliance system. Successful tooth alignment of both arches was achieved. The use of Invisalign appliance is an effective treatment option in adult patients with Class I malocclusion that requires incisor extraction due to moderate to severe mandibular anterior crowding.

  11. Orthodontic Treatment of a Mandibular Incisor Extraction Case with Invisalign

    Science.gov (United States)

    Zawawi, Khalid H.

    2014-01-01

    Mandibular incisor extraction for orthodontic treatment is considered an unusual treatment option because of the limited number of patients that meet the criteria for such treatment. Accurate diagnosis and treatment planning is essential to achieve the desired results. Adult orthodontic patients are increasingly motivated by esthetic considerations and reject the idea of conventional fixed appliances. In recent years, Invisalign appliances have gained tremendous attention for orthodontic treatment of adult patients to meet their esthetic demands. In this case report, a case of Class I malocclusion was treated with mandibular incisor extraction using the Invisalign appliance system. Successful tooth alignment of both arches was achieved. The use of Invisalign appliance is an effective treatment option in adult patients with Class I malocclusion that requires incisor extraction due to moderate to severe mandibular anterior crowding. PMID:25024852

  12. Glassfiber Post: An Alternative for Restoring Grossly Decayed Primary Incisors

    Science.gov (United States)

    Grover, Rashu

    2012-01-01

    ABSTRACT Restoration of primary incisors, which have been severely damaged by rampant caries or trauma, is a difficult task for the pediatric dentist. With the introduction of new adhesive systems and restorative materials, alternative approaches for treating these teeth have been proposed. This paper discusses the restoration of carious primary maxillary incisors using composite resin restoration reinforced with fiberglass post. Two case reports are presented here to describe the procedure. Over a 1 year period, the crowns have demonstrated good retention and esthetic results. How to cite this article: Mehra M, Grover R. Glassfiber Post: An Alternative for Restoring Grossly Decayed Primary Incisors. Int J Clin Pediatr Dent 2012;5(2):159-162. PMID:25206160

  13. Orthodontic treatment of a mandibular incisor extraction case with invisalign.

    Science.gov (United States)

    Zawawi, Khalid H

    2014-01-01

    Mandibular incisor extraction for orthodontic treatment is considered an unusual treatment option because of the limited number of patients that meet the criteria for such treatment. Accurate diagnosis and treatment planning is essential to achieve the desired results. Adult orthodontic patients are increasingly motivated by esthetic considerations and reject the idea of conventional fixed appliances. In recent years, Invisalign appliances have gained tremendous attention for orthodontic treatment of adult patients to meet their esthetic demands. In this case report, a case of Class I malocclusion was treated with mandibular incisor extraction using the Invisalign appliance system. Successful tooth alignment of both arches was achieved. The use of Invisalign appliance is an effective treatment option in adult patients with Class I malocclusion that requires incisor extraction due to moderate to severe mandibular anterior crowding.

  14. A new approach to incisor retention--the lingual spur retainer.

    LENUS (Irish Health Repository)

    McNamara, T G

    1996-08-01

    Late lower incisor crowding and incisor rotations remain a problem in orthodontics. We describe a new fixed retainer which is simple to use, allows physiological tooth movement, but prevents rotational and labio-lingual relapse.

  15. 不同冠延长术式处理上中切牙冠根折并桩核冠修复的三维有限元比较%Finite element analysis of the maxillary central incisor with traditional and modified crown lengthening surgery and post-core restoration in management of crown-root fracture

    Institute of Scientific and Technical Information of China (English)

    甄敏; 危伊萍; 胡文杰; 荣起国; 张豪

    2016-01-01

    traditional method.The maxillary central incisors with labial fracture at gingival margin level and with palatal fracture at or below the alveolar crest level are not the indication of the crown lengthening surgery.%目的 构建上中切牙不同冠根折类型行改良冠延长术后桩核冠修复的三维有限元模型,研究术后牙齿应力大小和分布情况,从力学角度对比分析常规和改良牙冠延长术的适应证.方法 采用显微CT扫描技术和三维激光扫描技术、DICOM数据直接建模法、逆向工程技术和有限元法,构建9种上中切牙冠根折类型行改良冠延长术后桩核冠修复的三维有限元模型(简称不同改良冠延长术模型),分析牙体、牙周和修复体各结构(牙本质、牙周膜、牙槽骨、桩、核)的等效应力(von Mises stress)峰值及其分布位置、牙周膜面积、牙周膜极限阈值,并与本课题组既往研究中常规冠延长术模型的相关结果进行比较.结果 不同改良牙冠延长术模型中不同结构的等效应力大小:牙本质>桩>核>牙槽骨>牙周膜;牙本质的应力峰值(44.37~ 80.58 MPa)出现在舌侧中央肩台处;改良冠延长术术后牙周膜面积减少了6%~28%,在相同折裂条件下,改良冠延长术模型保留的牙周膜面积大于常规冠延长术模型;改良冠延长术模型中仅B3L1m、B3L2m、B3L3m模型的牙周膜应力超过了牙周膜的极限阈值,而常规冠延长术模型中的B2L2c、B2L3c、B3Llc、B3L2c、B3L3c模型的牙周膜应力均超过了牙周膜的极限阈值.结论 改良冠延长术较常规法保留了相对多的牙周支持组织,有利于术牙的远期疗效;改良冠延长术的适应证范围大于常规冠延长术;唇侧折裂平齐龈缘且舌侧折裂至牙槽嵴顶及其根方的上前牙冠根折不是改良冠延长术的适应证.

  16. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

    International Nuclear Information System (INIS)

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  17. Transverse forces exerted on the maxillary incisors during laryngoscopy

    NARCIS (Netherlands)

    M.J.L. Bucx (Martin); M.H. van der Vegt (Marinus); C.J. Snijders (Chris); Th. Stijnen (Theo); P.R. Wesselink

    1996-01-01

    textabstractPurpose: In this study the effect of level of experience of the intubator on the forces applied by the Macintosh laryngoscope on the maxillary incisors in both the axial and transverse direction were investigated. Methods: Five groups of different levels of experience (15 per group), sta

  18. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha

    Science.gov (United States)

    2016-01-01

    The incisors of proboscideans (tusks and tushes) are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres), the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition). The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans. PMID:26756209

  19. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha.

    Directory of Open Access Journals (Sweden)

    Dimila Mothé

    Full Text Available The incisors of proboscideans (tusks and tushes are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres, the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition. The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans.

  20. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha.

    Science.gov (United States)

    Mothé, Dimila; Ferretti, Marco P; Avilla, Leonardo S

    2016-01-01

    The incisors of proboscideans (tusks and tushes) are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres), the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition). The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans. PMID:26756209

  1. Sex determination using the mesio-distal dimension of permanent maxillary incisors and canines in a modern Chilean population.

    Science.gov (United States)

    Peckmann, Tanya R; Logar, Ciara; Garrido-Varas, Claudia E; Meek, Susan; Pinto, Ximena Toledo

    2016-03-01

    The pelvis and skull have been shown to be the most accurate skeletal elements for the determination of sex. Incomplete or fragmentary bones are frequently found at forensic sites however teeth are often recovered in forensic cases due to their postmortem longevity. The goal of the present research was to investigate sexual dimorphism between the mesio-distal dimension of the permanent maxillary incisors and canines for the determination of sex in a contemporary Chilean population. Three hundred and three dental models (126 males and 177 females) from individuals ranging in age from 13 years to 37 years old were used from the School of Dentistry, University of Chile. The statistical analyses showed that only the central incisors and canines were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 59.7% to 65.0% for the univariate analysis and 60.1% to 66.7% for the multivariate analysis. Comparisons to other populations were made. Overall, the accuracies ranged from 54.4% to 63.3% with males most often identified correctly and females most often misidentified. The determination of sex from the mesio-distal width of incisors and canines in Chilean populations does not adhere to the Mohan and Daubert criteria and therefore would not be presented as evidence in court. PMID:26976465

  2. Molar-incisor hypomineralization: Prevalence, severity and clinical characteristics in 8- to 13-year-old children of Udaipur, India

    Directory of Open Access Journals (Sweden)

    Shubha Arehalli Bhaskar

    2014-01-01

    Full Text Available Background: The last couple of decades has seen an increasing interest in molar-incisor hypomineralization (MIH. Although the reported prevalence of MIH ranges from 2.4% to 40.2% worldwide, very little data is available from India. Objective: To assess the prevalence, clinical characteristics, distribution, severity and association with caries of MIH defects in children aged 8-13 years of Udaipur, Rajasthan. Study design: This cross-sectional descriptive study consisted of 1173 children aged 8-13 years selected by random sampling procedure. The European Academy of Pediatric Dentistry criteria were followed for MIH diagnosis. The presence of dental caries and treatment need for MIH-affected teeth were recorded as per the WHO criteria. Results: The prevalence of MIH in the children examined was 9.46%. Severity of the defects increased with the age of the children. Involvement of incisors increased when more First permanent molars (FPMs were affected. An average of 3.65 teeth was involved per MIH-affected individual. Significantly larger numbers of mandibular FPMs and maxillary central incisors were diagnosed with MIH. The association of dental caries was significantly higher with MIH-affected FPMs. Primary molars and permanent canines and premolars were also showed MIH like lesions in some of the MIH-affected children. Conclusion: MIH was observed in about 10% of the children examined. MIH-affected FPMs appear to be more vulnerable to early caries and subsequent pulp involvement with need for extensive dental treatment.

  3. SUPPLEMENTAL PERMANENT MAXILLARY LATERAL INCISOR: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Charlotte

    2014-01-01

    Full Text Available Supernumerary teeth , is defined as teeth that exceed the normal dental formula , regardless of their location and morphology it can be found in almost any region of the dental arch both in the primary and permanent dentition . Supernumerary teeth of orthodox shape and size that resemble normal teeth are called ‘supplemental teeth’. The s upplemental teeth are less common than supernumerary teeth and are often overlooked because of their normal shape and size. The s upplemental teeth may cause aesthetic problems , delayed eruption and crowding . T hey require early diagnosis and treatment to prevent complication s. There has been very few documented case s of unilateral supplemental lateral incisors. A case with unilateral supplemental permanent maxillary lateral incisor is presented. The etiology , types and treatment alternatives are discussed

  4. The effect of epidermal growth factor on neonatal incisor differentiation in the mouse.

    Science.gov (United States)

    Topham, R T; Chiego, D J; Gattone, V H; Hinton, D A; Klein, R M

    1987-12-01

    The effect of epidermal growth factor (EGF) on cellular differentiation of the neonatal mouse mandibular incisor was examined autoradiographically using tritiated thymidine ([3H]TDR) and tritiated proline ([3H]PRO). On days 0 (day of birth), 1, and 2, EGF was administered (3 micrograms/g body wt) sc to neonates. Mice were killed on Days 1, 4, 7, 10, and 13 after birth and were injected with either [3H]TDR or [3H]PRO 1 hr before death. [3H]TDR was used to analyze cell proliferation in eight cell types in the developing mouse incisor including upper (lingual) and lower (buccal) pulpal fibroblasts, preodontoblasts, inner and outer enamel epithelial cells (IEE and OEE), stratum intermedium (SI), stellate reticulum (SR), and periodontal ligament (PDL) fibroblasts. [3H]PRO was used to analyze protein synthesis in ameloblasts, and their secretion products (enamel and dentin), as well as PDL fibroblasts. The selected EGF injection scheme elicited acceleration of incisor eruption with minimal growth retardation. At Day 1, the upper and lower pulp, preodontoblasts, SI, and SR showed a significant decrease in labeling index (LI) 24 hr after a single EGF injection. After multiple injections (Days 0, 1, 2), two LI patterns were observed. In lower pulp, preodontoblasts, IEE, SI, SR, and OEE, a posteruptive change in LI was observed. In contrast, the upper pulp and PDL regions demonstrated a direct temporal relationship with eruption. Autoradiographic analysis with [3H]PRO indicated that EGF treatment caused significant increases in grain counts per unit area in ameloblast, odontoblast, and PDL regions studied. Significant differences were found in all four regions studied (ameloblasts, enamel, odontoblasts, dentin) at the 45-microns-tall ameloblast level as well as ameloblasts and odontoblasts at the 30-microns level at 13 days of age. The PDL demonstrated significant differences at all locations studied (base, 30 microns, 45 microns,) in 4-, 7-, and 13-day-old mice

  5. Pre-Prosthetic Orthodontic Implant Site Preparation for Management of Congenitally Unerupted Lateral Incisors – A Case Report

    OpenAIRE

    Kumar, K. Kiran; Kumar, Nettemu Sunil; Sowmya, Nettem; Tanveer, K.; K, Shameem; Kumar, Seetharam

    2013-01-01

    Congenital unilateral or bilateral absence of the maxillary lateral incisor teeth is one of the main reasons of concern for patients in addition to a challenge confronting the clinicians in terms of early investigations, accurate diagnosis and meticulous treatment planning. With growing patient demands for a functional as well as an esthetic treatment outcome, implant based oral rehabilitation has emerged as one of the most successful and predictable treatment approach in fulfilling both aspe...

  6. Mandibular Incisor Extraction Treatment of a Class I Malocclusion with Bolton Discrepancy: A Case Report

    OpenAIRE

    Bayram, Mehmet; ÖZER, Mete

    2007-01-01

    Many approaches for crowded mandibular anterior teeth are currently employed: distal movement of posterior teeth, lateral movement of canines, labial movement of incisors, interproximal enamel reduction, removal of premolars, removal of one or two incisors, and various combinations of the above. Selecting the best treatment is often difficult, and all guidelines do not apply to every case. Treatment by extraction of one single mandibular incisor is not popular in the orthodontic profession de...

  7. Longitudinal clinical and radiographic evaluation of severely intruded permanent incisors in a pediatric population.

    Science.gov (United States)

    Neto, José Jeová Siebra Moreira; Gondim, Juliana Oliveira; de Carvalho, Fernanda Matias; Giro, Elisa Maria Aparecida

    2009-10-01

    Intrusion is defined as the axial dislodgment of the tooth into its socket and is considered one of the most severe types of dental trauma. This longitudinal outcome study was undertaken to evaluate clinically and radiographically severely intruded permanent incisors in a population of children and adolescents. All cases were treated between September 2003 and February 2008 in a dental trauma service. Clinical and radiographic data were collected from 12 patients (eight males and four females) that represented 15 permanent maxillary incisors. Mean age at the time of injury was 8 years and 9 months (range 7-14 years and 8 months). Mean time elapsed to follow-up was 26.6 months (range 10-51 months). The analysis of data showed that tooth intrusion was twice as frequent in males. The maxillary central incisors were the most commonly intruded teeth (93.3%), and falling at home was the main etiologic factor (60%). More than half of the cases (53.3%) were multiple intrusions, 73.3% of the intruded teeth had incomplete root formation and 66.6% of the teeth suffered other injuries concomitant to intrusion. Immediate surgical repositioning was the treatment of choice in 66.7% of the cases, while watchful waiting for the tooth to return to its pre-injury position was adopted in 33.3% of the cases. The teeth that suffered additional injuries to the intrusive luxation presented a fivefold increased relative risk of developing pulp necrosis. The immature teeth had six times more chances of presenting pulp canal obliteration that the mature teeth and a lower risk of developing root resorption. The most frequent post-injury complications were pulp necrosis (73.3%), marginal bone loss (60%), inflammatory root resorption (40%), pulp canal obliteration (26.7%) and replacement root resorption (20%). From the results of this study, it was not possible to determine whether the type immediate treatment had any influence on the appearance of sequelae like pulp necrosis and root

  8. Existence and uniqueness for a class of double pyramidal central configurations with a concave pentagonal base

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Based on some necessary conditions for double pyramidal central configurations with a concave pentagonal base, for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configurations with a concave pentagonal base in 7-body problems are proved and the range of the ratio between radius and half-height is obtained, within which the 7 bodies involved form a central configuration or form uniquely a central configuration.

  9. Three-dimensional evaluation of upper anterior alveolar bone dehiscence after incisor retraction and intrusion in adult patients with bimaxillary protrusion malocclusion

    Institute of Scientific and Technical Information of China (English)

    Qing-yuan GUO; Shi-jie ZHANG; Hong LIU; Chun-ling WANG; Fu-lan WEI; Tao LV; Na-na WANG; Dong-xu LIU

    2011-01-01

    Objective: The purpose of this study was to evaluate three-dimensional (3D) dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage.Methods: Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted.Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion.A computed tomography (CT) scan was performed after placement of the miniscrews and treatment.The 3D reconstructions of pre- and post-CT data were used to assess the dehiscence of upper anterior alveolar bone.Results: The amounts of upper incisor retraction at the edge and apex were (7.64±1.68) and (3.91±2.10) mm,respectively,and (1.34±0.74) mm of upper central incisor intrusion.Upper alveolar bone height losses at labial alveolar ridge crest (LAC) and palatal alveolar ridge crest (PAC) were 0.543 and 2.612 mm,respectively,and the percentages were (6.49±3.54)% and (27.42±9.77)%,respectively.The shape deformations of LAC-labial cortex bending point (LBP) and PAC-palatal cortex bending point (PBP) were (15.37±5.20)° and (6.43±3.27)°,respectively.Conclusions: Thus,for adult patients with bimaxillary protrusion,mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion.Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss.

  10. Non-linear viscoelastic finite element analysis of the effect of the length of glass fiber posts on the biomechanical behaviour of directly restored incisors and surrounding alveolar bone.

    Science.gov (United States)

    Ferrari, Marco; Sorrentino, Roberto; Zarone, Fernando; Apicella, Davide; Aversa, Raffaella; Apicella, Antonio

    2008-07-01

    The study aimed at estimating the effect of insertion length of posts with composite restorations on stress and strain distributions in central incisors and surrounding bone. The typical, average geometries were generated in a FEA environment. Dentin was considered as an elastic orthotropic material, and periodontal ligament was coupled with nonlinear viscoelastic mechanical properties. The model was then validated with experimental data on displacement of incisors from published literature. Three post lengths were investigated in this study: root insertion of 5, 7, and 9 mm. For control, a sound incisor model was generated. Then, a tearing load of 50 N was applied to both sound tooth and simulation models. Post restorations did not seem to affect the strain distribution in bone when compared to the control. All simulated post restorations affected incisor biomechanics and reduced the root's deforming capability, while the composite crowns underwent a higher degree of deformation than the sound crown. No differences could be noticed in incisor stress and strain. As for the influence of post length, it was not shown to affect the biomechanics of restored teeth. PMID:18833761

  11. The orthodontic extraction of upper incisor tooth trauma%中切牙外伤拔除的正畸治疗

    Institute of Scientific and Technical Information of China (English)

    武霞; 袁东辉; 李仲影; 李娜

    2014-01-01

    Objective To explore the feasibility and key treatment points of orthodontic extraction of unilateral traumatized maxillary central incisors.Methods 19 patients (mean age 14.5 years old,16 males and 3 females) from 40 central incisor trauma cases were selected.10 of them were Angle Class Ⅰ malocclusion,7 were Class Ⅱ,and the other 2 were Angle Class Ⅱ malocclusion.All patients were treated by extraction of the traumatized central incisor and the first premolars in the other three quadrants.Pre and Post treatment analysis and comparisons were done.Results All 19 cases achieved satisfied outcomes.Extraction spaces were closed,the overject and overbite were normal,midlines were almost on,and the profiles were improved.Paired t test showed statistically significantdifferences in 4 dental indices.U1-NA° (from 27.5 to 23.3)L1-NB° (from 36.4 to 32.5) and L1-MP° (from 97.2 to 93.5) decreased,indicating a decrease of central incisor angulation,while U1-L1° (from 11.83 to 124.4) increased,indicating a decrease in incisor protrusion.For 2 soft tissue indices,statistically significant differences were also found.Ls-E (from 3.5 to 1.2 mm) and Li-E (from 4.1 to 1.5 mm) both decreased.Conclusions Individual treatment plan based on Bolton index analysis and effective anchorage control,the unconventional extraction plan could receive desired treatment outcome.%目的 探讨正畸拔除上颌单侧中切牙矫治模式的可行性及临床治疗的要点.方法 从40例切牙外伤正畸病例中,选出患者19例.其中安氏Ⅰ类错(牙合)10例,安氏Ⅱ类错(牙合)7例,安氏Ⅲ类错(牙合)2例;男16例,女3例,平均年龄14.5岁,均存在牙量与骨量不调需拔牙矫治病例.所有患者采取拔除外伤中切牙及其它三个象限第一前磨牙模式进行矫治.矫治后对临床资料做回顾性的研究,并进行临床疗效评价.结果 19例患者均取得较好的治疗效果,矫治后拔牙间隙关闭,前牙覆(牙合)覆盖正常,中线基

  12. Orthodontic Management of Congenitally Missing Maxillary Lateral Incisors: A Case Report

    Directory of Open Access Journals (Sweden)

    Sergio Paduano

    2014-01-01

    Full Text Available This case report describes the orthodontic treatment of a woman, aged 15 years, with permanent dentition, brachyfacial typology, with congenitally missing maxillary lateral incisors. Multibracket straightwire fixed appliance was used to open the space for dental implant placement, and treat the impaired occlusion. The missing lateral incisors were substituted with oral implants.

  13. Preformed resin-veneered stainless steel crowns for restoration of primary incisors.

    Science.gov (United States)

    Croll, T P; Helpin, M L

    1996-05-01

    Stainless steel crown forms with bonded resin veneers for primary incisors are commercially available to dentists. This type of preveneered crown was developed to serve as a convenient, durable, reliable, and esthetic solution to the difficult challenge of restoring severely carious primary incisors. This article describes preveneered crowns, reviews their advantages and disadvantages, and details a technique for placement of such restorations.

  14. The quality of root fillings remaining in mandibular incisors after root-end cavity preparation

    NARCIS (Netherlands)

    Wu, MK; de Schwartz, FBC; van der Sluis, LWM; Wesselink, PR

    2001-01-01

    Aim The aim of this study was to determine the quality of root fillings remaining in mandibular incisors after root-end resection and root-end cavity preparation. Methodology Roots of 40 mandibular incisors. 12 mm in length. were divided into two groups and instrumented using a balanced force techni

  15. Lower incisor extraction treatment with the Invisalign® technique: three case reports.

    Science.gov (United States)

    Giancotti, Aldo; Garino, Francesco; Mampieri, Gianluca

    2015-03-01

    The extraction of a lower incisor can lead to satisfactory orthodontic results for patients with moderate to severe lower incisor crowding. Invisalign(®) is a treatment modality for such treatments, moving teeth with precision and reducing inconvenience for the patient. Three case reports are presented in this article supporting the above statements.

  16. Fractal systems of central places based on intermittency of space-filling

    International Nuclear Information System (INIS)

    Highlights: → The idea of intermittency is introduced into central place model. → The revised central place model suggests incomplete space filling. → New central place fractals are presented for urban analysis. → The average nearest distance is proposed to estimate the fractal dimension. → The concept of distance-based space is replaced by that of dimension-based space. - Abstract: The central place models are fundamentally important in theoretical geography and city planning theory. The texture and structure of central place networks have been demonstrated to be self-similar in both theoretical and empirical studies. However, the underlying rationale of central place fractals in the real world has not yet been revealed so far. This paper is devoted to illustrating the mechanisms by which the fractal patterns can be generated from central place systems. The structural dimension of the traditional central place models is d = 2 indicating no intermittency in the spatial distribution of human settlements. This dimension value is inconsistent with empirical observations. Substituting the complete space filling with the incomplete space filling, we can obtain central place models with fractional dimension D < d = 2 indicative of spatial intermittency. Thus the conventional central place models are converted into fractal central place models. If we further integrate the chance factors into the improved central place fractals, the theory will be able to explain the real patterns of urban places very well. As empirical analyses, the US cities and towns are employed to verify the fractal-based models of central places.

  17. Angle Class I malocclusion treated with lower incisor extraction

    Directory of Open Access Journals (Sweden)

    Vanessa Leal Tavares Barbosa

    2013-06-01

    Full Text Available In planning orthodontic cases that include extractions as an alternative to solve the problem of negative space discrepancy, the critical decision is to determine which teeth will be extracted. Several aspects must be considered, such as periodontal health, orthodontic mechanics, functional and esthetic alterations, and treatment stability. Despite controversies, extraction of teeth to solve dental crowding is a therapy that has been used for decades. Premolar extractions are the most common, but there are situations in which atypical extractions facilitate mechanics, preserve periodontal health and favor maintenance of the facial profile, which tends to unfavorably change due to facial changes with age. The extraction of a lower incisor, in selected cases, is an effective approach, and literature describes greater post-treatment stability when compared with premolar extractions. This article reports the clinical case of a patient with Angle Class I malocclusion and upper and lower anterior crowding, a balanced face and harmonious facial profile. The presence of gingival and bone recession limited large orthodontic movements. The molars and premolars were well occluded, and the discrepancy was mainly concentrated in the anterior region of the lower dental arch. The extraction of a lower incisor in the most ectopic position and with compromised periodontium, associated with interproximal stripping in the upper and lower arches, was the alternative of choice for this treatment, which restored function, providing improved periodontal health, maintained facial esthetics and allowed finishing with a stable and balanced occlusion. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO, as part of the requirements for obtaining the BBO Diplomate title.

  18. [Molar incisor hypomineralization (MIH)--a literature review].

    Science.gov (United States)

    Gotler, M; Ratson, T

    2010-04-01

    MIH was defined by Weerheijm (2001) as "hypomineralisation of systemic origin of 1-4 permanent first molars, frequently associated with affected incisors". The prevalence of MIH varies between 2.8% and 25%, dependent upon the study. At their sixth congress in 2003, The European Association of pediatric dentistry defined criteria for diagnosis of the phenomena. It included the presence of demarcated opacity, posteruptive enamel breakdown, atypical restoration, extracted molar due to MIH and unerupted teeth. According to the teeth involved and to the time of the crown formation, researches focused on environmental and systemic conditions as possible reasons for MIH.The etiologies were divided into five groups: Exposure to environmental contaminants, pre/peri and neonatal problems, exposure to fluoride, common childhood illnesses and medically compromised children. The clinical implications include highly sensitive teeth, difficulty to achieve adequate anesthesia, behavioral problems and anxiety, rapid progression of caries and the esthetic implications. A six step approach to management was described suggested: risk identification, early diagnosis, remineralization and desensitization, prevention of caries and posteruption breakdown, restorations and extractions and finally maintenance. Restoring an affected molar can vary from adhesive intra coronal restorations (resin composite is the material of choice) to extra coronal restorations (e.g. preformed metal crown). Esthetic solutions to affected incisors may include microabrasion (that shows little improvement) and resin composite or porcelain veneer. The key for a successful treatment is early diagnosis, intense follow up and usage of remineralizating agents as soon as the teeth erupt. There is still need for further research to clarify the etiological factors and improve the durability of restoration in affected teeth.

  19. Notching and anterior beveling on fossil horse incisors: Indicators of domestication?

    Science.gov (United States)

    Rogers, Richard A.; Rogers, Laurine A.

    1988-01-01

    One of the lines of evidence cited for possible late Pleistocene human control of horses has been the presence of notching and anterior beveling on horse incisor teeth recovered from upper and middle Paleolithic sites in Europe. Similar forms of wear have been found on the incisor teeth of wild horses from early and middle Pleistocene deposits in North America. Notching appears partly due to malocclusion and chipping. The causes of beveling are less certain but may involve the eating of bark. Therefore, the presence of notching and anterior beveling on horse incisor teeth may not be a reliable indicator of human control.

  20. A development-based compartmentalization of the Drosophila central brain

    OpenAIRE

    Pereanu, Wayne; Kumar, Abilasha; Jennett, Arnim; Reichert, Heinrich; Hartenstein, Volker

    2010-01-01

    The neuropile of the Drosophila brain is subdivided into anatomically discrete compartments. Compartments are rich in terminal neurite branching and synapses; they are the neuropile domains in which signal processing takes place. Compartment boundaries are defined by more or less dense layers of glial cells, as well as long neurite fascicles. These fascicles are formed during the larval period when the approximately 100 neuronal lineages that constitute the Drosophila central brain differenti...

  1. Weighting links based on edge centrality for community detection

    Science.gov (United States)

    Sun, Peng Gang

    2014-01-01

    Link weights have the equally important position as links in complex networks, and they are closely associated with each other for the emergence of communities. How to assign link weights to make a clear distinction between internal links of communities and external links connecting communities is of vital importance for community detection. Edge centralities provide a powerful approach for distinguishing internal links from external ones. Here, we first use edge centralities such as betweenness, information centrality and edge clustering coefficient to weight links of networks respectively to transform unweighted networks into weighted ones, and then a weighted function that both considers links and link weights is adopted on the weighted networks for community detection. We evaluate the performance of our approach on random networks as well as real-world networks. Better results are achieved on weighted networks with stronger weights of internal links of communities, and the results on unweighted networks outperform that of weighted networks with weaker weights of internal links of communities. The availability of our findings is also well-supported by the study of Granovetter that the weak links maintain the global integrity of the network while the strong links maintain the communities. Especially in the Karate club network, all the nodes are correctly classified when we weight links by edge betweenness. The results also give us a more comprehensive understanding on the correlation between links and link weights for community detection.

  2. Traumatic impact loading on human maxillary incisor: A Dynamic finite element analysis

    Directory of Open Access Journals (Sweden)

    K Jayasudha

    2015-01-01

    Full Text Available Background: The most vulnerable tooth is the maxillary incisor, which sustains 80% of dental injuries. Dynamic Finite element analysis is used to understand the biomechanics of fracture of maxillary incisor under traumatic impact loading. Aim: The aim was to investigate the stress patterns of an upper incisor in a three-dimensional (3D model under traumatic impact loading in various directions. Materials and Methods: A 3D finite element model of the upper incisor and surrounding tissues was established. A sinusoidal force of 800N was applied over a period of 4 ms. Results: Software performs a series of calculations and mathematical equations and yields the simulation results. During the horizontal impact (F1, stresses were concentrated in the cervical area of the crown, reaching peak stress of 125 MPa at 2 ms. Conclusion: A horizontal force exerted on the labial surface of the tooth tends to cause cervical crown fractures, oblique crown root fractures, and oblique root fractures.

  3. Molar Incisor Hypomineralization: An Epidemiological Study with Prevalence and Etiological Factors in Indian Pediatric Population

    OpenAIRE

    Mishra, Apurva; Ramesh K Pandey

    2016-01-01

    ABSTRACT Aims: To determine the prevalence of molar incisor hypomineralization (MIH) in Indian children and to analyze the possible etiological factors. Materials and methods: First permanent molars and all permanent incisors were examined in 1,369 children aged 8 to 12 years. Examinations were performed by two calibrated observers. The subjects were evaluated using judgment criteria proposed by Weerheijm et al in 2003. The parents accompanying children were given a questionnaire regarding pr...

  4. Treatment of Two Canals in All Mandibular Incisor Teeth in the Same Patient

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    Vandana B. Kokane

    2014-01-01

    Full Text Available The main reason for unfavourable outcome in endodontic treatment of mandibular incisor is the inability to detect the presence of second canal. Pain even after extirpation of complete pulp tissue from root canal of vital teeth is the main indication of hidden canals. The present case report is also on pain because of another neglected canal in all mandibular incisors in the same patient.

  5. Lateral incisor agenesis, canine impaction and characteristics of supernumerary teeth in a South European male population

    OpenAIRE

    Livas, Christos; Bornstein, Michael; Delli, Konstantina

    2013-01-01

    Objective: To assess the prevalence of lateral incisor agenesis impacted canines and supernumerary teeth in a young adult male population. Materials and Methods: The panoramic radiographs of 1745 military students (mean age: 18.6 ± 0.52 years) who attended the Center of Aviation Medicine of the Armed Forces of Greece during the period 1997-2011 were initially analyzed for lateral incisor agenesis by two observers. After exclusion of the known orthodontic cases, a subgroup of 1636 examinees (m...

  6. Treating dental crowding with mandibular incisor extraction in an Angle Class I patient

    OpenAIRE

    Gislana Braga Machado

    2015-01-01

    Mandibular dental crowding often encourages patients to seek orthodontic treatment. The orthodontist should decide between protrusion of incisors or decrease in dental volume so as to achieve proper alignment and leveling. The present study reports the treatment of an Angle Class I malocclusion adolescent female brachyfacial patient with severe mandibular dental crowding, increased curve of Spee and deep overbite. The patient was treated with extraction of a mandibular incisor. This case was ...

  7. Root development of permanent lateral incisor in cleft lip and palate children: A radiographic study

    Directory of Open Access Journals (Sweden)

    Amarlal Deepti

    2007-01-01

    Full Text Available Objective: The objective of this study was to compare the root development of lateral incisor on the cleft side with the root development of its contralateral tooth in cleft lip and palate children. Setting: Cleft lip and palate wing, Meenakshi Ammal Dental College and Hospital, Chennai, South India. Materials and Methods: A sample of 96 orthopantamograms of patients with unilateral or bilateral cleft lip and/or cleft palate was selected, regardless of sex and race. Main Outcome Measure: Orthopantamograms were analyzed for root development of lateral incisor on the cleft and noncleft side. Associated anomalies like hypodontia, supernumerary teeth, malformed lateral incisors and root development of canine, if present, were recorded. Findings and Conclusions: Root development of permanent lateral incisor was delayed on the cleft side compared to the noncleft side. There was a statistically significant relationship between levels of root development of lateral incisors on the cleft side within the different study groups ( P < 0.05. Incidence of hypodontia increased in proportion to cleft severity. Frequency of missing second premolars, supernumerary teeth and malformed lateral incisors increased in cleft lip and palate patients. Root development of canine showed a slight delay on the cleft side when compared to the canine on the noncleft side.

  8. When is a central bank governor replaced? Evidence based on a new data set

    NARCIS (Netherlands)

    Dreher, Axel; Sturm, Jan-Egbert; de Haan, Jakob

    2010-01-01

    Using new data on the term in office of central bank governors for a large set of countries for 1970-2005, we estimate a model for the probability that a central bank governor is replaced before the end of his legal term in office. We formulate hypotheses based on the literature on the determinants

  9. An investigation on the influence of tin foil substitute contamination on bond strength between resin denture teeth and the denture base: An in vitro study

    OpenAIRE

    Sapna Bhaskaran; Hallikerimath, R B

    2012-01-01

    Statement of Problem: The problem of acrylic resin denture teeth separating from their denture base remains a major problem in prosthodontic practice and is frustrating to the patients as well as the dentists. Purpose: This study investigated the influence of tin foil substitute contamination on bond strength between acrylic resin denture teeth and their denture base. Materials and Methods: A total of 80 modified acrylic resin maxillary left central incisors were processed to their dent...

  10. New prediction equations for the estimation of maxillary mandibular canine and premolar widths from mandibular incisors and mandibular first permanent molar widths: A digital model study

    Science.gov (United States)

    Shahid, Fazal; Khamis, Mohd Fadhli

    2016-01-01

    Objective The primary aim of the study was to generate new prediction equations for the estimation of maxillary and mandibular canine and premolar widths based on mandibular incisors and first permanent molar widths. Methods A total of 2,340 calculations (768 based on the sum of mandibular incisor and first permanent molar widths, and 1,572 based on the maxillary and mandibular canine and premolar widths) were performed, and a digital stereomicroscope was used to derive the the digital models and measurements. Mesiodistal widths of maxillary and mandibular teeth were measured via scanned digital models. Results There was a strong positive correlation between the estimation of maxillary (r = 0.85994, r2 = 0.7395) and mandibular (r = 0.8708, r2 = 0.7582) canine and premolar widths. The intraclass correlation coefficients were statistically significant, and the coefficients were in the strong correlation range, with an average of 0.9. Linear regression analysis was used to establish prediction equations. Prediction equations were developed to estimate maxillary arches based on Y = 15.746 + 0.602 × sum of mandibular incisors and mandibular first permanent molar widths (sum of mandibular incisors [SMI] + molars), Y = 18.224 + 0.540 × (SMI + molars), and Y = 16.186 + 0.586 × (SMI + molars) for both genders, and to estimate mandibular arches the parameters used were Y = 16.391 + 0.564 × (SMI + molars), Y = 14.444 + 0.609 × (SMI + molars), and Y = 19.915 + 0.481 × (SMI + molars). Conclusions These formulas will be helpful for orthodontic diagnosis and clinical treatment planning during the mixed dentition stage. PMID:27226963

  11. The study of prevalence of maxillary incisor forms among dentist faculty students and patients of Shahed University: 2014

    Directory of Open Access Journals (Sweden)

    Mohadese hashemzehi

    2015-12-01

    Full Text Available Background and Aim: Selecting the appropriate form of anterior teeth in patients without teeth is important factor in restoring the missing beauty of the patient. For this purpose, the study of natural teeth in terms of investigating the relationship between dimensions and forms and its prevalence in the Iranian community is essential. Materials and Methods: This analytic and descriptive study was done with participation of 300 eligible patients and students with different genders. Where a maxillary impression was taken and poured in yellow stone. They were measured for length and 3 horizontal distances on the upper incisor consisting of cervical width, middle width and incisal width, by digital caliper with 0.01mm accuracy, and the prevalence of tooth form determined. Normal distribution variables were analyzed with logistic regression. Results: Analysis indicated that Average length and width of the maxillary central incisor in order is 9.12 ± 0.87 mm and is 8.44 ± 0.59 mm and average ratio of length and width is 0.92 ± 0.08 mm Horizontal and vertical dimensions of the clinical crown in the men slightly more than women, and the prevalence of tooth form thus obtained: oval incisior (53%, tapered-square (21.3%, tapered (16.7%, and square (9%.  A significant correlation only could be shown between shape and width (p<0.05. Conclusion: With increasing the width of the central maxillary tooth, oval shape was observed more frequently than square form. Meantime of choosing dental form, oval form considered more because of its high incidence.

  12. Non-invasive management of fused upper incisors

    Directory of Open Access Journals (Sweden)

    Pouran Samimi

    2012-01-01

    Full Text Available The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case of fusion of 7 and 8, and also 9 and 10 teeth which was treated with a nonendodontic and nonsurgical conservative approach. Patient was a healthy18-year-old female with chief complaint of bad-looking teeth that in intraoral examination revealed the fusion of 7 and 8, and also 9 and 10 teeth. The space between the mesial of the 6 and 11 teeth was reconstructed. Diastema between the fused teeth was closed. A new lateral tooth was replaced between the fused teeth (7 and 8 and 6 tooth with direct fiber-reinforced composite. The space between the fused teeth (9 and 10 and also tooth 11 was partially closed. Gingival papillas were reconstructed using pink composite. The mandibular anterior missing teeth were replaced with rochett bridge. At the end of treatment the esthetic of the patient was improved. As the treatment was not invasive, major complications are not expected; however, there is potential for eventual long-term periodontal problems due to poor oral hygiene. Debonding of the rochett bridge may happen as well.

  13. Two cases with supernumerary teeth in lower incisor region.

    Science.gov (United States)

    Yokose, Taishi; Sakamoto, Teruo; Sueishi, Kenji; Yatabe, Kenichi; Tsujino, Keiichirou; Kubo, Shuhei; Yakushiji, Masashi; Yamaguchi, Hideharu

    2006-02-01

    Abnormalities in number of teeth are occasionally noted in clinical cases. Many theories have been proposed as regards the causes of the occurrence of supernumerary teeth, including atavism theory, mechanical tooth germ separation theory, tissue induction theory, and dental laminar morphological disturbance theory. However, none of these theories alone offers a sufficient explanation for this phenomenon. The incidence of supernumerary permanent teeth is approximately 1-3%. These are the maxillary anterior teeth, the maxillary molars, and the maxillo-mandibular premolars in terms of descending order of site of occurrence. On the other hand, incidence in the mandibular anterior tooth area, of which there have been few detailed reports, is about 0.01%, a markedly low value. In this paper, we report two rare cases of supernumerary teeth in the mandibular incisor area. We discuss their etiology and orthodontic treatment, and detail a differential diagnosis between the normal and supernumerary teeth. We found that it was difficult to establish a clear etiology and differentiation between the normal and supernumerary teeth. PMID:16924155

  14. A development-based compartmentalization of the Drosophila central brain

    Science.gov (United States)

    Pereanu, Wayne; Kumar, Abilasha; Jennett, Arnim; Reichert, Heinrich; Hartenstein, Volker

    2010-01-01

    The neuropile of the Drosophila brain is subdivided into anatomically discrete compartments. Compartments are rich in terminal neurite branching and synapses; they are the neuropile domains in which signal processing takes place. Compartment boundaries are defined by more or less dense layers of glial cells, as well as long neurite fascicles. These fascicles are formed during the larval period when the approximately 100 neuronal lineages that constitute the Drosophila central brain differentiate. Each lineage forms an axon tract with a characteristic trajectory in the neuropile; groups of spatially related tracts congregate into the brain fascicles that can be followed from the larva throughout metamorphosis into the adult stage. In this paper we provide a map of the adult brain compartments and the relevant fascicles defining compartmental boundaries. We have identified the neuronal lineages contributing to each fascicle, which allowed us to directly compare compartments of the larval and adult brain. Most adult compartments can be recognized already in the early larval brain where they form a “protomap” of the later adult compartments. Our analysis highlights the morphogenetic changes shaping the Drosophila brain; the data will be important for studies that link early acting genetic mechanisms to the adult neuronal structures and circuits controlled by these mechanisms. PMID:20533357

  15. Development-based compartmentalization of the Drosophila central brain.

    Science.gov (United States)

    Pereanu, Wayne; Kumar, Abilasha; Jennett, Arnim; Reichert, Heinrich; Hartenstein, Volker

    2010-08-01

    The neuropile of the Drosophila brain is subdivided into anatomically discrete compartments. Compartments are rich in terminal neurite branching and synapses; they are the neuropile domains in which signal processing takes place. Compartment boundaries are defined by more or less dense layers of glial cells as well as long neurite fascicles. These fascicles are formed during the larval period, when the approximately 100 neuronal lineages that constitute the Drosophila central brain differentiate. Each lineage forms an axon tract with a characteristic trajectory in the neuropile; groups of spatially related tracts congregate into the brain fascicles that can be followed from the larva throughout metamorphosis into the adult stage. Here we provide a map of the adult brain compartments and the relevant fascicles defining compartmental boundaries. We have identified the neuronal lineages contributing to each fascicle, which allowed us to compare compartments of the larval and adult brain directly. Most adult compartments can be recognized already in the early larval brain, where they form a "protomap" of the later adult compartments. Our analysis highlights the morphogenetic changes shaping the Drosophila brain; the data will be important for studies that link early-acting genetic mechanisms to the adult neuronal structures and circuits controlled by these mechanisms. PMID:20533357

  16. Ground-based Fourier transform infrared spectroscopy in central Mexico

    Science.gov (United States)

    Plaza, Eddy; Stremme, Wolfgang; Bezanilla, Alejandro; Baylon, Jorge; Grutter, Michel; Blumenstock, Thomas; Hase, Frank

    2014-05-01

    Altzomoni is a high altitude station in central Mexico (19.12 N, 98.65 W, 4000 m a.s.l.) for continuous measurements of various atmospheric parameters. It is located within the Izta-Popo National Park and is operated remotely from the UNAM campus. Since May 2012, high resolution solar absorption spectra have been recorded from this site using a FTIR from Bruker (HR120/5) equipped with MCT, InSb and InGaAs detectors and various optical filters. In this contribution we present a detailed description of the measurement site and the instrumental set-up including a record of the instrumental line-shapes (modulation efficiency and phase error) obtained from cell measurements and analyzed with the LINEFIT code. A preliminary analysis of almost two years of spectra recorded at the Altzomoni site resulting in profile retrievals of four NDACC gases O3, CO, HF and HCl is presented. The retrieval code PROFFIT is used and the Averaging Kernels and an error analysis are used to describe the quality of the measurements. The annual cycles in the time series of O3 and CO are presented and discussed, as well as some examples of anomalies due to volcanic gas emissions of HF and HCl are shown. The presented work is part of an effort to certify this station as part of the NDACC international network.

  17. Biofilm-based central line-associated bloodstream infections.

    Science.gov (United States)

    Yousif, Ammar; Jamal, Mohamed A; Raad, Issam

    2015-01-01

    Different types of central venous catheters (CVCs) have been used in clinical practice to improve the quality of life of chronically and critically ill patients. Unfortunately, indwelling devices are usually associated with microbial biofilms and eventually lead to catheter-related bloodstream infections (CLABSIs).An estimated 250,000-400,000 CLABSIs occur every year in the United States, at a rate of 1.5 per 1,000 CVC days and a mortality rate of 12-25 %. The annual cost of caring for patients with CLABSIs ranges from 296 million to 2.3 billion dollars.Biofilm formation occurs on biotic and abiotic surfaces in the clinical setting. Extensive studies have been conducted to understand biofilm formation, including different biofilm developmental stages, biofilm matrix compositions, quorum-sensing regulated biofilm formation, biofilm dispersal (and its clinical implications), and multi-species biofilms that are relevant to polymicrobial infections.When microbes form a matured biofilm within human hosts through medical devices such as CVCs, the infection becomes resistant to antibiotic treatment and can develop into a chronic condition. For that reason, many techniques have been used to prevent the formation of biofilm by targeting different stages of biofilm maturation. Other methods have been used to diagnose and treat established cases of CLABSI.Catheter removal is the conventional management of catheter associated bacteremia; however, the procedure itself carries a relatively high risk of mechanical complications. Salvaging the catheter can help to minimize these complications.In this article, we provide an overview of microbial biofilm formation; describe the involvement of various genetic determinants, adhesion proteins, organelles, mechanism(s) of biofilm formation, polymicrobial infections, and biofilm-associated infections on indwelling intravascular catheters; and describe the diagnosis, management, and prevention of catheter-related bloodstream infections

  18. Observations on the eruption of the permanent incisor teeth of farmed Javan rusa deer (Cervus timorensis russa) in New Caledonia.

    Science.gov (United States)

    Bianchi, M; Hurlin, J C; Lebel, S; Chardonnet, P

    1997-08-01

    The eruption of the permanent incisor teeth of 14 farmed Javan rusa deer (Cervus timorensis russa) of known birth date and their live weights were observed about every 2 weeks from 12 to 30 months of age. The permanent incisor pattern was 11, 14-17 months; 12, 18-23 months; 13, 20-26 months; and 14, 22-27 months. There was no significant relationship between body weight and timing of permanent incisor eruption. PMID:16031978

  19. Transoral robotic surgery of the central skull base: preclinical investigations.

    Science.gov (United States)

    Fernandez-Nogueras, F J J; Katati, M J; Arraez Sanchez, M A; Molina Martinez, M; Sanchez Carrion, M

    2014-06-01

    In this study we explored possible applications of the da Vinci system in approaching the skull base at optic chiasm level on two cryopreserved cadavers, using an entirely transoral robotic technique (TORS). We used a standard 12 mm endoscopy and 8 mm terminals. Bone drilling was performed manually. The da Vinci system is equipped with very good illumination and 3D viewing, thus providing excellent vision and great maneuverability even in the less accessible areas of the skull. Our experience demonstrates that an entirely transoral skull base robotic approach to this complex anatomical region has many advantages as compared to traditional techniques. PMID:24077869

  20. Centralized computer-based controls of the Nova Laser Facility

    International Nuclear Information System (INIS)

    This article introduces the overall architecture of the computer-based Nova Laser Control System and describes its basic components. Use of standard hardware and software components ensures that the system, while specialized and distributed throughout the facility, is adaptable. 9 references, 6 figures

  1. Prevalence assessment of root dilaceration in permanent incisors

    Directory of Open Access Journals (Sweden)

    Beatriz Feitosa da Silva

    2012-12-01

    Full Text Available INTRODUCTION: Root dilaceration is a dental anomaly characterized by an abnormal curvature of the dental root, which can cause problems during eruption and complications in the orthodontic and endodontic treatment or extraction. OBJECTIVE: The aim of this study was to determine the prevalence of root dilaceration in permanent incisors in an oral radiology clinic in the city of João Pessoa / PB, Brazil. METHODS: The sample consisted of 548 patients who allowed assessments of their dental radiographs, a total of 3,948 examined teeth. Each tooth was examined according to the occurrence of root dilaceration, regarding type (mild, moderate or severe, root third that it was in and direction of the root. The angle formed by the root deviation in relation to the long tooth axis was obtained by means of a diagram printed on transparent acetate, placed over the radiograph. RESULTS: The results were analyzed with SPSS software (Statistical Package for Social Sciences version 13.0, performing an exploratory data analysis. The prevalence of root dilaceration in the studied sample was 1.03% (41 cases, with higher incidence in males (65.8%, being the superior lateral incisor the most affected teeth (78%. The most prevalent type of root dilaceration was the mild one (73.1%, occurring more in the apical third (90.2% and with distal direction of the root (95.1%. CONCLUSION: Considering these results, it is emphasized the importance of performing a diagnostic radiographic examination prior to planning a treatment in permanent anterior teeth.INTRODUÇÃO: a dilaceração radicular é uma anomalia dentária caracterizada por uma curvatura anormal na raiz do dente que pode causar problemas na erupção e complicações durante movimentação ortodôntica, tratamento endodôntico ou exodontia. OBJETIVO: o objetivo do presente trabalho foi verificar a prevalência da dilaceração radicular em incisivos permanentes, em uma clínica de radiologia odontológica da

  2. 成人安氏Ⅰ类双颌前突患者的上颌切牙区牙槽骨体积%Alveolar bone volume around upper incisors in adult patients with Class Ⅰ bimaxillary protrusion

    Institute of Scientific and Technical Information of China (English)

    刘璐; 李荣荣; 刘梦臖; 张琰; 刘东旭

    2015-01-01

    Objective To investigate the alveolar bone volume around upper incisors in adult patients with Class Ⅰbimaxillary protrusion and provide a reference for orthodontic diagnosis and treatment planning.Methods Twenty-two cases with Class Ⅰ bimaxillary protrusion (bimaxillary protrusion group)and Eighteen cases with individual normal occlusion (control group)were recruited.Lateral cephalograms and cone beam computed tomography(CBCT)scan-nings were taken respectively and the alveolar bone volume around four upper incisors in each subject were measured by Mimics 16.0.Results In bimaxillary protrusion group,alveolar bone volume around upper incisors decreased com-pared to the control group (P <0.05),apart from labial root apex zone of central incisors,labial root apex and palatal crest zone of the lateral incisors.Besides,alveolar crest zone,middle root zone,palatal alveolar bone,total alveolar bone of the central incisors,labial alveolar bone,palatal alveolar bone,total alveolar bone of the lateral incisors and total alveolar bone volume of four upper incisors in bimaxillary protrusion group were decreased compared to the control group (P <0.001).Conclusion The alveolar bone volume around upper incisors in adult patients with Class Ⅰ bima-xillary protrusion is fewer than that in the subjects with normal occlusion.It should be more cautious in the process of treatment planning,especially retraction or intrusion of the upper incisors.%目的:研究成人安氏Ⅰ类双颌前突患者上颌切牙区牙槽骨体积,为正畸诊断及治疗计划制定提供参考。方法选择安氏Ⅰ类双颌前突患者22例(双颌前突组)及个别正常牙合志愿者18例(对照组),分别拍摄头颅侧位片及锥体束计算机断层扫描(CBCT),利用 Mimics 16.0测量上颌4颗切牙牙槽骨体积。结果双颌前突组上颌切牙区牙槽骨体积除中切牙唇侧根尖区、侧切牙唇侧根尖区及腭侧牙槽嵴顶区外,

  3. Stability of Spatial Structure of Urban Agglomeration in China Based on Central Place Theory

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper brings forward the concept of stability of the spatial structure of urban agglomeration (UA) based on Central Place Theory by introducing centrality index and fractal theory. Before assessment, K=4 is selected as parameter to calculate centrality index and fractal dimension (K represents the quantitive relationship between city and the counties in Central Place Theory), and then found the number of nodes, the type of spatial structure, the spatial allocation of nodes with different hierarchy affecting the stability of spatial structure. According to spatial contact direction and the level of stability, UAs in China are classified into five types. Finally, it is posed as a further question that how to use hierarchical relation K=6 and K=7 in central place system to coordinate with the assessment of stability of spatial structure is brought forward.

  4. Eigenvector Centrality Based on Shared Research Topics in a Scientific Community

    OpenAIRE

    Volpentesta, Antonio P.; Felicetti, Alberto M.

    2010-01-01

    In this paper we propose a weighted multi-hypergraph as logical structure to model relationships between researchers and interest groups that join them on the base of shared research topics in a given scientific community. The well known concept of eingenvector centrality for graphs is extended to weighted multi-hypergraphs and we present a model instantiation for centrality analysis in the Pro-VE scientific community.

  5. Incremental Algorithms for Network Management and Analysis based on Closeness Centrality

    OpenAIRE

    Sariyuce, Ahmet Erdem; Kaya, Kamer; Saule, Erik; Catalyurek, Umit V.

    2013-01-01

    Analyzing networks requires complex algorithms to extract meaningful information. Centrality metrics have shown to be correlated with the importance and loads of the nodes in network traffic. Here, we are interested in the problem of centrality-based network management. The problem has many applications such as verifying the robustness of the networks and controlling or improving the entity dissemination. It can be defined as finding a small set of topological network modifications which yiel...

  6. Sequelae of trauma to primary maxillary incisors. I. Complications in the primary dentition.

    Science.gov (United States)

    Borum, M K; Andreasen, J O

    1998-02-01

    Two hundred and eighty-seven children with a total of 545 traumatized primary upper incisors were followed using standardized procedures until the age of 10. Extraction was the only treatment offered when intervention was necessary. The immediate as well as the long-term consequences of trauma were studied on the basis of this material. Consequences in the primary dentition comprised: color changes (53%), pulp necrosis (25%), pulp canal obliteration (36%), gingival retraction (6%), permanent displacement after luxation (5-22%), pathological root resorption (1-10%) as well as disturbances in physiological root resorption (4%) and, lastly, premature tooth loss (46%). In a multivariate analysis of the development of pulp necross in primary teeth after trauma, the following decisive factors were found: age of the patient at the time of injury, degree of displacement of the tooth as well as the degree of loosening and presence of crown fracture. The factors found to influence development of pulp canal obliteration were: displacement of the tooth at time of injury as well as detectable physiologic root resorption at time of trauma. The presence of crown fracture seemed to decrease the risk of obliteration. The need for scientifically based treatment strategies for managing and reducting complications after trauma in the primary dentition is stressed.

  7. A comparative in vivo and in vitro L-band EPR study of irradiated rat incisors

    International Nuclear Information System (INIS)

    L-band (∼1GHz) EPR has the potential to measure the absorbed radiation dose in human teeth inside the mouth (in vivo analyses). One crucial point in the development of the method is to know if dosimetry evaluation carried out in vivo after accidental exposures can be reliably based on calibration curves built in vitro. The aim of the present work is to specifically address this point. First, we compared L-band in vitro and in vivo analyses in irradiated rat teeth and estimated the possible loss in in vivo experiments due to rat movements and mouth proximity. Second, the lower pair of rat incisors were analysed by L-band EPR before and after irradiation (50Gy), first on the living rat, then on the same dead rat, finally after extraction of the teeth. X-band powder spectra were also taken after crushing of the two teeth. Irradiations of dead rats and extracted teeth were also carried out. Comparing L-band spectra obtained with living rats and removed heads does not show any significant difference due to possible small rat movements or breathing. Relative standard deviations of the amplitudes of the dosimetric signal are quite high (27-54%). Nevertheless, it seems to be a tendency to have higher signals in irradiated extracted teeth than in irradiated animals

  8. Orthodontic treatment of a mandibular incisor fenestration resulting from a broken retainer.

    Science.gov (United States)

    Farret, Marcel M; Farret, Milton M B; da Luz Vieira, Gustavo; Assaf, Jamal Hassan; de Lima, Eduardo Martinelli S

    2015-08-01

    This article describes the orthodontic relapse with mandibular incisor fenestration in a 36-year-old man who had undergone orthodontic treatment 21 years previously. The patient reported that his mandibular 3 × 3 bonded retainer had been partially debonded and broken 4 years earlier. The mandibular left lateral incisor remained bonded to the retainer and received the entire load of the incisors; consequently, there was extreme labial movement of the root, resulting in dental avulsion. As part of the treatment, the root was repositioned lingually using a titanium-molybdenum segmented archwire for 8 months, followed by endodontic treatment, an apicoectomy, and 4 months of alignment and leveling of both arches. The treatment outcomes were excellent, and the tooth remained stable, with good integrity of the mesial, distal, and lingual alveolar bones and periodontal ligament. The 1-year follow-up showed good stability of the results. PMID:26232842

  9. A Novel approach of Esthetic Management and preserving Vitality of Dilacerated Permanent Maxillary Lateral Incisor

    Science.gov (United States)

    Ravi, GR

    2016-01-01

    ABSTRACT Dilaceration of the permanent tooth usually is a consequence of traumatic injuries to the primary teeth. Although it may appear anywhere in the long axis of the tooth, i.e., crown, cementoenamel junction, or root, most often the root is involved. However, crown dilaceration is a rare condition representing 3% of the total injuries. Maxillary incisors are more susceptible to such injury and affected tooth may either erupt buccally or lingually or remain impacted. Hitherto, the treatment options also differ as per the clinical scenario. This article proposes a novel technique of restoring esthetic function of the affected permanent maxillary lateral incisor with crown-root dilaceration while preserving the vitality of tooth. How to cite this article: Achary RC, Ravi GR. A Novel approach of Esthetic Management and preserving Vitality of Dilacerated Permanent Maxillary Lateral Incisor. Int J Clin Pediatr Dent 2016;9(2):152-155. PMID:27365939

  10. A Novel approach of Esthetic Management and preserving Vitality of Dilacerated Permanent Maxillary Lateral Incisor.

    Science.gov (United States)

    Achary, Ravindranath C; Ravi, G R

    2016-01-01

    Dilaceration of the permanent tooth usually is a consequence of traumatic injuries to the primary teeth. Although it may appear anywhere in the long axis of the tooth, i.e., crown, cementoenamel junction, or root, most often the root is involved. However, crown dilaceration is a rare condition representing 3% of the total injuries. Maxillary incisors are more susceptible to such injury and affected tooth may either erupt buccally or lingually or remain impacted. Hitherto, the treatment options also differ as per the clinical scenario. This article proposes a novel technique of restoring esthetic function of the affected permanent maxillary lateral incisor with crown-root dilaceration while preserving the vitality of tooth. How to cite this article: Achary RC, Ravi GR. A Novel approach of Esthetic Management and preserving Vitality of Dilacerated Permanent Maxillary Lateral Incisor. Int J Clin Pediatr Dent 2016;9(2):152-155.

  11. Premature loss of the maxillary primary incisors: effect on speech production.

    Science.gov (United States)

    Gable, T O; Kummer, A W; Lee, L; Creaghead, N A; Moore, L J

    1995-01-01

    The residual effect of premature loss due to extraction of the four maxillary primary incisors on speech production was studied. The articulation of twenty-six subjects who had their teeth extracted before the age of five years was evaluated at eight, nine, or ten years old and compared with the articulation of an age-matched comparison group with normal exfoliation of their incisors. T-tests for related measures revealed no statistically significant differences between the group with premature loss and the comparison group. These results suggest that loss of maxillary incisors in children younger than five years is not likely to result in defective articulation while the teeth are missing or when the permanent dentition is acquired.

  12. Caribbean and Central American Women's Feminist Inquiry through Theater-Based Action Research

    Science.gov (United States)

    Sánchez Ares, Rocío

    2015-01-01

    Feminist action research interrogates gendered dynamics in the development of a collective consciousness. A group of immigrant Latina women (Latinas) from the Caribbean and Central America employed community-based theater as an instrument to mobilize diverse audiences against discriminatory practices and policies. Based on their theater work, I…

  13. Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst

    OpenAIRE

    2011-01-01

    Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens) is rare and accounts for 5% of all dentigerous cysts. ...

  14. Endodontic Treatment and Esthetic Management of a Geminated Central Incisor Bearing a Talon Cusp

    Directory of Open Access Journals (Sweden)

    Elif Tarım Ertaş

    2014-01-01

    Full Text Available Gemination with talon cusps is an uncommon morphologic dental anomaly, characterized by the formation of clinically wide tooth that can cause significant aesthetic and clinical problems including esthetic impairment, pain, caries susceptibility, and tooth crowding. These morphological dental anomalies have specific treatment needs due to the abnormal morphology and need virtuous radiologic diagnosis. Multidisciplinary approach can supply success of the treatment plan that can provide esthetic and occlusal requirements. In this case report, the multidisciplinary approach for the treatment of geminated tooth with talon cusp is presented with the clinical and radiographic findings.

  15. Management of Talons Cusp associated with Primary Central Incisor: A Rare Case Report

    OpenAIRE

    Bahadure, Rakesh N.; Thosar, Nilima; Jain, Eesha S

    2012-01-01

    ABSTRACT The talon cusp is a relatively rare dental developmental anomaly characterized by cusp-like projections, usually observed on the lingual surface of the affected tooth. Normal enamel covers the cusp and fuses with the lingual aspect of the tooth. The cusp may or may not contain an extension of the pulp. The condition can occur in both the primary and permanent dentitions. However, the occurrence of anomalous cusp is rather infrequent in the primary dentition. Little data is available ...

  16. Treating dental crowding with mandibular incisor extraction in an Angle Class I patient

    Directory of Open Access Journals (Sweden)

    Gislana Braga Machado

    2015-06-01

    Full Text Available Mandibular dental crowding often encourages patients to seek orthodontic treatment. The orthodontist should decide between protrusion of incisors or decrease in dental volume so as to achieve proper alignment and leveling. The present study reports the treatment of an Angle Class I malocclusion adolescent female brachyfacial patient with severe mandibular dental crowding, increased curve of Spee and deep overbite. The patient was treated with extraction of a mandibular incisor. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO as a requirement for the title of certified by the BBO.

  17. Planar Cell Polarity Protein Localization in the Secretory Ameloblasts of Rat Incisors

    OpenAIRE

    Nishikawa, Sumio; Kawamoto, Tadafumi

    2012-01-01

    The localization of the planar cell polarity proteins Vang12, frizzled-3, Vang11, and Celsr1 in the rat incisors was examined using immunocytochemistry. The results showed that Vang12 was localized at two regions of the Tomes’ processes of inner enamel–secretory ameloblasts in rat incisors: a proximal and a distal region. In contrast, frizzled-3 was localized at adherens junctions of the proximal and distal areas of inner enamel– and outer enamel–secretory ameloblasts, where N-cadherin and β-...

  18. Treating dental crowding with mandibular incisor extraction in an Angle Class I patient.

    Science.gov (United States)

    Machado, Gislana Braga

    2015-01-01

    Mandibular dental crowding often encourages patients to seek orthodontic treatment. The orthodontist should decide between protrusion of incisors or decrease in dental volume so as to achieve proper alignment and leveling. The present study reports the treatment of an Angle Class I malocclusion adolescent female brachyfacial patient with severe mandibular dental crowding, increased curve of Spee and deep overbite. The patient was treated with extraction of a mandibular incisor. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as a requirement for the title of certified by the BBO. PMID:26154463

  19. Bilateral Supernumerary Deciduous Maxillary Lateral Incisors with Fusion: Report of a Rare Case.

    Science.gov (United States)

    Ghaderi, Faezeh; Rafiee, Azade

    2016-03-01

    Dental anomaly in number, size and shape might be due to excessive activation of dental lamina during the morpho-differentiation stage. Fusion is one of the most unusual and rare anomalies of shape of the teeth. It frequently involves the supernumerary teeth resulting in a challenging differential diagnosis with gemination. Dental anomalies may result in different problems such as delayed eruption and crowding; thus, early diagnosis is required for effective intervention and proper in-time treatment. The case reported here is a 4-year-old girl with bilateral supernumerary primary maxillary lateral incisors associated with fusion between primary maxillary left lateral incisor and supernumerary lateral tooth. PMID:26966712

  20. Maxillary lateral incisors with two canals and two separate curved roots

    Directory of Open Access Journals (Sweden)

    Ajit George Mohan

    2012-01-01

    Full Text Available Variation in the roots and root canal anatomy seems to be the norm rather than an exception. For a successful endodontic treatment, a clinician should have a thorough knowledge of the internal and external dental anatomy and its variations. Maxillary lateral incisors usually exhibit single canal with a single root. In this case, clinical examination and radiographs clearly demonstrates the presence of two root canals with two separate curved roots. This case report emphasizes the need for attention during endodontic management of maxillary lateral incisors.

  1. Spatial drought reconstructions for central High Asia based on tree rings

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Keyan [Lanzhou University, Key Laboratory of Western Chinese Environmental Systems (MOE), Center for Arid Environment and Paleoclimate Research (CAEP), Lanzhou (China); Columbia University, Tree-Ring Lab, Lamont-Doherty Earth Observatory, Palisades, NY (United States); Davi, Nicole; Cook, Edward; Li, Jinbao; D' Arrigo, Rosanne [Columbia University, Tree-Ring Lab, Lamont-Doherty Earth Observatory, Palisades, NY (United States); Gou, Xiaohua; Chen, Fahu [Lanzhou University, Key Laboratory of Western Chinese Environmental Systems (MOE), Center for Arid Environment and Paleoclimate Research (CAEP), Lanzhou (China)

    2010-11-15

    Spatial reconstructions of drought for central High Asia based on a tree-ring network are presented. Drought patterns for central High Asia are classified into western and eastern modes of variability. Tree-ring based reconstructions of the Palmer drought severity index (PDSI) are presented for both the western central High Asia drought mode (1587-2005), and for the eastern central High Asia mode (1660-2005). Both reconstructions, generated using a principal component regression method, show an increased variability in recent decades. The wettest epoch for both reconstructions occurred from the 1940s to the 1950s. The most extreme reconstructed drought for western central High Asia was from the 1640s to the 1650s, coinciding with the collapse of the Chinese Ming Dynasty. The eastern central High Asia reconstruction has shown a distinct tendency towards drier conditions since the 1980s. Our spatial reconstructions agree well with previous reconstructions that fall within each mode, while there is no significant correlation between the two spatial reconstructions. (orig.)

  2. Differences between dentitions with palatally and labially located maxillary canines observed in incisor width, dental morphology and space conditions

    DEFF Research Database (Denmark)

    Artmann, L; Larsen, H J; Sørensen, H B;

    2010-01-01

    To analyze the interrelationship between incisor width, deviations in the dentition and available space in the dental arch in palatally and labially located maxillary ectopic canine cases.......To analyze the interrelationship between incisor width, deviations in the dentition and available space in the dental arch in palatally and labially located maxillary ectopic canine cases....

  3. CentiServer: A Comprehensive Resource, Web-Based Application and R Package for Centrality Analysis.

    Directory of Open Access Journals (Sweden)

    Mahdi Jalili

    Full Text Available Various disciplines are trying to solve one of the most noteworthy queries and broadly used concepts in biology, essentiality. Centrality is a primary index and a promising method for identifying essential nodes, particularly in biological networks. The newly created CentiServer is a comprehensive online resource that provides over 110 definitions of different centrality indices, their computational methods, and algorithms in the form of an encyclopedia. In addition, CentiServer allows users to calculate 55 centralities with the help of an interactive web-based application tool and provides a numerical result as a comma separated value (csv file format or a mapped graphical format as a graph modeling language (GML file. The standalone version of this application has been developed in the form of an R package. The web-based application (CentiServer and R package (centiserve are freely available at http://www.centiserver.org/.

  4. A study of the management of 55 traumatically intruded permanent incisor teeth in children.

    LENUS (Irish Health Repository)

    Stewart, C

    2009-01-01

    These were to examine the main presenting, treatment and outcome factors for intruded permanent incisors in children, the effect of apical development and degree of intrusion on decisions on repositioning, the effect of apical development status on the maintenance of pulp vitality and the time of pulp extirpation and to compare the decisions made to the advice given in existing clinical guidelines.

  5. An evolutionarily conserved enhancer regulates Bmp4 expression in developing incisor and limb bud.

    Directory of Open Access Journals (Sweden)

    Dolrudee Jumlongras

    Full Text Available To elucidate the transcriptional regulation of Bmp4 expression during organogenesis, we used phylogenetic footprinting and transgenic reporter analyses to identify Bmp4 cis-regulatory modules (CRMs. These analyses identified a regulatory region located ∼46 kb upstream of the mouse Bmp4 transcription start site that had previously been shown to direct expression in lateral plate mesoderm. We refined this regulatory region to a 396-bp minimal enhancer, and show that it recapitulates features of endogenous Bmp4 expression in developing mandibular arch ectoderm and incisor epithelium during the initiation-stage of tooth development. In addition, this enhancer directs expression in the apical ectodermal ridge (AER of the developing limb and in anterior and posterior limb mesenchyme. Transcript profiling of E11.5 mouse incisor dental lamina, together with protein binding microarray (PBM analyses, allowed identification of a conserved DNA binding motif in the Bmp4 enhancer for Pitx homeoproteins, which are also expressed in the developing mandibular and incisor epithelium. In vitro electrophoretic mobility shift assays (EMSA and in vivo transgenic reporter mutational analyses revealed that this site supports Pitx binding and that the site is necessary to recapitulate aspects of endogenous Bmp4 expression in developing craniofacial and limb tissues. Finally, Pitx2 chromatin immunoprecipitation (ChIP demonstrated direct binding of Pitx2 to this Bmp4 enhancer site in a dental epithelial cell line. These results establish a direct molecular regulatory link between Pitx family members and Bmp4 gene expression in developing incisor epithelium.

  6. Effect of incisor inclination changes on cephalometric points a and b

    International Nuclear Information System (INIS)

    The position of cephalometric points A and B are liable to be affected by alveolar remodelling caused by orthodontic tooth movement during incisor retraction. This study was conducted to evaluate the change in positions of cephalometric points A and B in sagittal and vertical dimensions due to change in incisor inclinations. Methods: Total sample of 31 subjects were recruited into the study. The inclusion criteria were extraction of premolars in upper and lower arches, completion of growth and orthodontic treatment. The exclusion criteria were patients with craniofacial anomalies and history of orthodontic treatment. By superimposition of pre and post treatment tracings, various linear and angular parameters were measured. Various tests and multiple linear regression analysis were performed to determine changes in outcome variables. Statistically significant p-value was <0.05. Results:One-sample t-test showed that change in position of only point A was statistically significant which was 1.61mm (p<0.01) in sagittal direction and 1.49mm (p<0.01) in vertical direction. Multiple linear regression analysis showed that if we retrocline upper incisor by 100, the point A will move superiorly by 0.6mm. Conclusions: Total change in the position of point A is in a downward and forward direction. Total Change in upper incisors inclinations causes change in position of point A only in vertical direction. (author)

  7. Growth and the modeling/remodeling of the alveolar bone of the rat incisor.

    Science.gov (United States)

    Merzel, José; Salmon, Cristiane R

    2008-07-01

    The modeling and remodeling of the rat incisor alveolar bone was followed as the animals grew. The weight of the hemimandible, the length of the socket, and the width of the lower incisor were measured. Osteoclasts and resorption areas were identified by tartrate-resistant acid phosphatase staining. Fluorochrome markers were used to detect and measure osteogenic activities. In the socket related to the periodontal ligament, osteoclasts appeared in scattered sites as well as isolated sites of osteogenic activity, apparently without any variation related to the age of the animals. At the socket facing the dental follicle of young rats, the inner surface was lined with osteoclasts. The number of osteoclasts decreased steadily as the rats grew. In 1-year-old rats, in addition to a few scattered osteoclasts, the internal aspect of the labial wall showed some sites lined with osteoblasts and cement lines indicative of prior bone formation. In young rats, there was a continuous osteogenic activity at the external surface of this wall. The thickness of the labial wall of the socket remained apparently constant; therefore, bone resorption must have occurred at the internal side of the wall. Such osteogenic activity was not observed in old rats. The main forces acting on rat incisors, biting and eruption, are continuous through the life of the animals. Thus, these results indicate that the modeling of the alveolar bone related to the dental follicle, in young rats, can only be associated with another force, specifically, the growth of the incisor. PMID:18461598

  8. Molar Incisor Hypomineralization: An Epidemiological Study with Prevalence and Etiological Factors in Indian Pediatric Population

    Science.gov (United States)

    Pandey, Ramesh K

    2016-01-01

    ABSTRACT Aims: To determine the prevalence of molar incisor hypomineralization (MIH) in Indian children and to analyze the possible etiological factors. Materials and methods: First permanent molars and all permanent incisors were examined in 1,369 children aged 8 to 12 years. Examinations were performed by two calibrated observers. The subjects were evaluated using judgment criteria proposed by Weerheijm et al in 2003. The parents accompanying children were given a questionnaire regarding pre- and postnatal history of the children. Results: A total of 191 children were diagnosed with MIH with a prevalence of 13.9%. Chi-square/Fisher exact test was used to compare the dichotomous variables. The relative risk with its 95% confidence interval was calculated to find the risk of clinical infections, such as chicken pox, jaundice, renal disorders, cardiac disorders, and affected molars with sex and type of delivery. Pre- and postnatal history of infection in a child was significantly correlated with the prevalence of MIH. Conclusion: The prevalence of MIH was 13.9% in the age group of 8 to 12 years. Prenatal and postnatal infections play an important role in hypomineralization of molars and incisors. How to cite this article: Mishra A, Pandey RK. Molar Incisor Hypomineralization: An Epidemiological Study with Prevalence and Etiological Factors in Indian Pediatric Population. Int J Clin Pediatr Dent 2016;9(2):167-171. PMID:27365942

  9. The effect of fluoride on enamel and dentin formation in the uremic rat incisor

    NARCIS (Netherlands)

    Lyaruu, Donacian; Bronckers, Antonius; Santos, Fernando; Mathias, Robert; Besten, Pamela Den

    2008-01-01

    Renal impairment in children is associated with tooth defects that include enamel pitting and hypoplasia. However, the specific effects of uremia on tooth formation are not known. In this study, we used rat mandibular incisors, which continuously erupt and contain all stages of tooth formation, to c

  10. Lateral incisor agenesis, canine impaction and characteristics of supernumerary teeth in a South European male population

    NARCIS (Netherlands)

    Delli, Konstantina; Livas, Christos; Bornstein, Michael M

    2013-01-01

    OBJECTIVE: To assess the prevalence of lateral incisor agenesis impacted canines and supernumerary teeth in a young adult male population. MATERIALS AND METHODS: The panoramic radiographs of 1745 military students (mean age: 18.6 ± 0.52 years) who attended the Center of Aviation Medicine of the Arme

  11. Comparison of the Fracture Resistance of 3 Different Posts in Restoring Extensively Damaged Primary Maxillary Incisors

    Directory of Open Access Journals (Sweden)

    F. Mojarad

    2013-10-01

    Full Text Available Introduction & Objective: The management of mutilated primary incisors in early childhood caries is a clinical challenge. This study's purpose was to compare the resistance strength of 3 different types of posts in restoring broken primary incisors: (1 composite posts, (2 ortho-dontic wire posts and (3 quartz fiber posts. Materials & Methods: This semi experimental in vitro study was performed on 27 extracted human primary maxillary incisors. The coronal portion of specimens was sectioned 1-mm above the cementoenamel junction. Complete pulpectomy was performed for all specimens. The post space was created using a straight fissure bur approximately 3 mm. Samples were randomly divided into 3 groups. Group 1(composite posts and composite core, group 2(quartz fiber posts and composite core and group 3 (orthodontic ? wire posts and composite core. Mounted specimens were subjected for fracture strength on an instron testing ma-chine at 45 angles. Results: Mean fracture strength value for group 1 was 248.9± 72.36 N, group 2 was 446.7±116.4 N and group 3 was 365.6± 31.3. This result showed significant differences among the three groups. Conclusion: Quartz fiber posts showed greater fracture strength for extensively damaged primary incisors than composite posts and orthodontic wire posts. (Sci J Hamadan Univ Med Sci 2013; 20 (3:240-246

  12. Lyapunov-Based Control Scheme for Single-Phase Grid-Connected PV Central Inverters

    NARCIS (Netherlands)

    Meza, C.; Biel, D.; Jeltsema, D.; Scherpen, J. M. A.

    2012-01-01

    A Lyapunov-based control scheme for single-phase single-stage grid-connected photovoltaic central inverters is presented. Besides rendering the closed-loop system globally stable, the designed controller is able to deal with the system uncertainty that depends on the solar irradiance. A laboratory p

  13. Nitrogen phosphoric fertilizer production technology on the base of Central Kyzylkum phosphorites and ammonium nitrate melt

    OpenAIRE

    Shavkat Namazov; Akhmed Reymov; Nazarkul Pirmanov; Rashid Kurbaniyazov

    2012-01-01

    The process of obtaining nitrogen phosphoric fertilizer by introduction Central Kyzylkum phosphates and ammonium nitrate melt is studied. On the base of these results production technology diagram for nitrogen phosphoric fertilizer is offered. The given technology was approved and developed at the functioning devices of OJSC “NAVOIAZOT” ammonium nitrate shop.

  14. Nitrogen phosphoric fertilizer production technology on the base of Central Kyzylkum phosphorites and ammonium nitrate melt

    Directory of Open Access Journals (Sweden)

    Shavkat Namazov

    2012-11-01

    Full Text Available The process of obtaining nitrogen phosphoric fertilizer by introduction Central Kyzylkum phosphates and ammonium nitrate melt is studied. On the base of these results production technology diagram for nitrogen phosphoric fertilizer is offered. The given technology was approved and developed at the functioning devices of OJSC “NAVOIAZOT” ammonium nitrate shop.

  15. Understanding Urban Spatial Structure of Shanghai Central City Based on Mobile Phone Data

    Institute of Scientific and Technical Information of China (English)

    Niu; Xinyi; Ding; Liang; Song; Xiaodong; Zhang; Qingfei

    2015-01-01

    Taking Shanghai Central City as its case study, this paper presents an approach to exploring the urban spatial structure through mobile phone positioning data. Firstly, based on base station location data and mobile phone signaling data, the paper analyses the number of users connecting to each base station, and further generates the maps of mobile phone user density through kernel density analysis. We move on to calculate the multi-day average user density based on a time frame of 10:00 and 23:00 at workdays and 15:00 and 23:00 at weekends for Shanghai Central City. Then, through spatial aggregation and density classifi cation on the density maps of 10:00 at workdays and 15:00 at weekends, we identify the ranks and functions of public centers within Shanghai Central City. Lastly, we identify residential areas, business off ice areas, and leisure areas in Shanghai Central City and measure the degree of functional mix by comparing the ratio of day and night user density as well as the user density at nighttime of workdays and weekends.

  16. Contemporary approaches to reducing the risks of central counterparties based on the use of marginal contributions

    Directory of Open Access Journals (Sweden)

    Utkin Viktor Sergeyevich

    2012-07-01

    Full Text Available To protect their own interests central counterparties has developed a number of procedures, including payment of guarantee margin by trading members as a means to ensure their positions. This article discusses a number of approaches, which attempt to simulate the risks of the Central Committee, as well as calculating the amount of margin and other resources in the event of insolvency. These approaches are based on the simulation of the three main types: (a statistical modeling; (b optimization modeling, and (c model of option pricing. The author incorporates the basic provisions of models.

  17. AphidBase: A centralized bioinformatic resource for annotation of the pea aphid genome

    OpenAIRE

    Legeai, Fabrice; Shigenobu, Shuji; Gauthier, Jean-Pierre; Colbourne, John; Rispe, Claude; Collin, Olivier; Richards, Stephen; Wilson, Alex C. C.; Tagu, Denis

    2010-01-01

    AphidBase is a centralized bioinformatic resource that was developed to facilitate community annotation of the pea aphid genome by the International Aphid Genomics Consortium (IAGC). The AphidBase Information System designed to organize and distribute genomic data and annotations for a large international community was constructed using open source software tools from the Generic Model Organism Database (GMOD). The system includes Apollo and GBrowse utilities as well as a wiki, blast search c...

  18. Organic and inorganic content of fluorotic rat incisors measured by FTIR spectroscopy

    Science.gov (United States)

    Porto, Isabel Maria; Saiani, Regina Aparecida; Chan, K. L. Andrew; Kazarian, Sergei G.; Gerlach, Raquel Fernanda; Bachmann, Luciano

    2010-09-01

    Details on how fluoride interferes in enamel mineralization are still controversial. Therefore, this study aimed at analyzing the organic contents of fluorosis-affected teeth using Fourier Transformation Infrared spectroscopy. To this end, 10 male Wistar rats were divided into two groups: one received 45 ppm fluoride in distilled water for 60 days; the other received distilled water only. Then, the lower incisors were removed and prepared for analysis by two FTIR techniques namely, transmission and micro-ATR. For the first technique, the enamel was powdered, whereas in the second case one fluorotic incisor was cut longitudinally for micro-ATR. Using transmission and powdered samples, FTIR showed a higher C-H content in the fluorotic enamel compared with control enamel ( p < 0.05, n = 4 in the flurotic, and n = 5 in the control group). Results from the micro-ATR-FTIR spectroscopic analysis on one longitudinally cut incisor carried out at six points reveal a higher C-H bond content at the surface of the enamel, with values decreasing toward the dentine-enamel junction, and reaching the lowest values at the subsuperficial enamel. These results agree with the morphological data, which indicate that in the rat incisor the fluorotic lesion is superficial, rather than subsuperficial, as in the case of human enamel. The results also suggest that the increased C-H bond content may extend toward the more basal enamel (intraosseous), indicating that fluorotic enamel may intrinsically contain more protein. Finally, particularly when coupled to ATR, FTIR is a suitable tool to study the rat incisor enamel, which is a largely used model of normal and abnormal amelogenesis. Further studies along this line may definitely answer some questions regarding protein content in fluorotic enamel as well as their origin.

  19. One Odontogenic Cell-Population Contributes to the Development of the Mouse Incisors and of the Oral Vestibule

    Science.gov (United States)

    Hovorakova, Maria; Lochovska, Katerina; Zahradnicek, Oldrich; Domonkosova Tibenska, Kristina; Dornhoferova, Michaela; Horakova-Smrckova, Lucie; Bodorikova, Silvia

    2016-01-01

    The area of the oral vestibule is often a place where pathologies appear (e.g., peripheral odontomas). The origin of these pathologies is not fully understood. In the present study, we traced a cell population expressing Sonic hedgehog (Shh) from the beginning of tooth development using Cre-LoxP system in the lower jaw of wild-type (WT) mice. We focused on Shh expression in the area of the early appearing rudimentary incisor germs located anteriorly to the prospective incisors. The localization of the labelled cells in the incisor germs and also in the inner epithelial layer of the vestibular anlage showed that the first very early developmental events in the lower incisor area are common to the vestibulum oris and the prospective incisor primordia in mice. Scanning electron microscopic analysis of human historical tooth-like structures found in the vestibular area of jaws confirmed their relation to teeth and thus the capability of the vestibular tissue to form teeth. The location of labelled cells descendant of the early appearing Shh expression domain related to the rudimentary incisor anlage not only in the rudimentary and functional incisor germs but also in the externally located anlage of the oral vestibule documented the odontogenic potential of the vestibular epithelium. This potential can be awakened under pathological conditions and become a source of pathologies in the vestibular area. PMID:27611193

  20. 安氏I类错(牙合)儿童上颌切牙唇腭侧齿槽厚度的CBCT研究%Maxillary incisors' dento-alveolar analysis of class I children using cone-beam CT

    Institute of Scientific and Technical Information of China (English)

    韩剑丽; 刘进; 葛元输; 彭兆伟

    2012-01-01

    Objective: The aim of this study was to evaluate the thickness of labial and palatal alveolar bone and labial bony curvature in maxillary anterior teeth of children using CBCT images. Method: Twenty-five patients (9 males,16 females),with mean age of 12.5 years were included in this study. Three-dimensional (3D) images were reformatted through CBCT. The incisor labio-palatal inclination,the thickness of labial and palatal alveolar bone,the labial bony curvature angle below root apex and the distance from root apex to the deepest point of labial bony curvature were measured using New Tom NNT programme. Paired t test was performed using SPSS 13.0 software package for Windows. Result: Mean thickness of labial plate 2 mm below CEJ was (0.96±0.32)mm at central incisor,(0.78±0.32)mm at lateral incisor. Mean thickness of palatal plate 2 mm below CEJ was (1.53±0.40)mm of central incisor,(1.12±0.48)mm of lateral incisor. Labio-palatal inclination was 114.59±5.25 of central incisor,111.75 ±5.98 of lateral incisor. Labial bony curvature angle was 145.70°± 11.09° and 156.92°±8.33°,respectively. Distance between root apex and the deepest point of labial bony curvature of central incisor was (2.88±1.49)mm,(2.69±0.99)mm of lateral incisor. Conclusion:The central incisor is more labial inclination than the lateral incisor. The thickness of maxillary anterior labial plate was very thin and the palatal plate was relatively thick. The maxillary incisor root apex was closer to the labial cortical bone than to the palatal cortical bone.%目的:采用CBCT影像测量安氏I类错(牙合)患儿上颌前牙唇倾度及前牙唇腭侧齿槽骨的厚度,探讨上颌切牙与其支持骨的空间位置关系.方法:选取深圳市儿童医院口腔正畸科2010.1~2012.1年间就诊的正畸患儿25名,年龄11~14岁,平均12.5岁,男9例,女16例.Angle I类轻度错(牙合)畸形.上前牙排列良好,无严重拥挤.所有病例均拍摄CBCT影像,在重建后的图像下

  1. Bacterial penetration of the root canal of intact incisor teeth after a simulated traumatic injury.

    Science.gov (United States)

    Love, R M

    1996-12-01

    One of the aims in treating traumatised teeth is to maintain the vitality of the pulp or allow conditions favourable for pulp revascularisation. However, infection of the pulp and root canal system may prevent this. A number of pathways have been proposed that allow bacteria to invade the root canal system, however most of these pathways cannot account for pulp infection in teeth that did not sustain injury to the periodontal attachment. Enamel/dentine cracks have been proposed as a portal for bacterial invasion of seemingly intact teeth and the aim of this study was to determine if bacteria could invade the root canal system after a simulated traumatic episode. Twenty intact and sound upper central incisors were chosen and prepared. One tooth was selected as a sterility control and the external crown surface of the remaining 19 teeth was subjected to infection with Streptococcus gordonii in a bacterial microleakage model. Over 7 days samples of growth media from the root canal system were taken and tested for bacteria. Sixteen of the teeth did not demonstrate bacterial invasion over the time frame. These teeth were then prepared for testing in a pendulum impact device and were subjected to a blow which did not fracture the crowns or dislodge the tooth from its simulated alveolus. The teeth were then prepared and tested in the bacterial microleakage model. After impact seven of the teeth demonstrated bacterial invasion of the root canal system (P = 0.002). These teeth were then reprepared for testing in the bacterial microleakage model. The crowns of five teeth, selected at random, were coated with two layers of light cured unfilled resin, the remaining two were used as positive controls. All the teeth coated with resin did not demonstrate bacterial invasion (P = 0.00), while the positive controls demonstrated invasion. The results suggested that enamel/dentine infractions were pathways for bacterial invasion of the root canal system of traumatised teeth. The

  2. Anti-triangle centrality-based community detection in complex networks.

    Science.gov (United States)

    Jia, Songwei; Gao, Lin; Gao, Yong; Wang, Haiyang

    2014-06-01

    Community detection has been extensively studied in the past decades largely because of the fact that community exists in various networks such as technological, social and biological networks. Most of the available algorithms, however, only focus on the properties of the vertices, ignoring the roles of the edges. To explore the roles of the edges in the networks for community discovery, the authors introduce the novel edge centrality based on its antitriangle property. To investigate how the edge centrality characterises the community structure, they develop an approach based on the edge antitriangle centrality with the isolated vertex handling strategy (EACH) for community detection. EACH first calculates the edge antitriangle centrality scores for all the edges of a given network and removes the edge with the highest score per iteration until the scores of the remaining edges are all zero. Furthermore, EACH is characterised by being free of the parameters and independent of any additional measures to determine the community structure. To demonstrate the effectiveness of EACH, they compare it with the state-of-the art algorithms on both the synthetic networks and the real world networks. The experimental results show that EACH is more accurate and has lower complexity in terms of community discovery and especially it can gain quite inherent and consistent communities with a maximal diameter of four jumps. PMID:25014378

  3. THE INDEPENDENCE OF CENTRAL BANKS IN CENTRAL AND EASTERN EUROPE-A MONETARY POLICY STRATEGY BASED APPROACH

    Directory of Open Access Journals (Sweden)

    Popescu Iulian Vasile

    2013-06-01

    Full Text Available The present paper aims to examine the trends of the last decade and a half of central banks independence (CBI in Central and Eastern European countries on the road to the euro adoption and to compare the results with those identified in the case of the European Central Bank (ECB. We approached CBI from the perspective of monetary policy strategies central banks (CBs use. The main results show increasing independence during the selected time frame for all monetary authorities subject to analysis, regardless of the applied monetary policy strategy; superior average levels of CBI in CEE countries oriented to inflation targeting compared to those using the exchange rate as nominal anchor; higher degree of independence of ECB in relation to monetary authorities that use an inflation targeting strategy; the simultaneous presence of a significant level of independence, low inflation and stronger economic development in CEE members where CB is geared towards inflation targeting compared to CBs that implement a strategy of exchange rate targeting.

  4. Relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction

    Directory of Open Access Journals (Sweden)

    Anísio Bueno de Carvalho

    2012-12-01

    Full Text Available OBJECTIVE: The purpose was to obtain information about the relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction. METHODS: Seventy-three patients with canine impaction and 73 control patients, without canine impaction, were evaluated. The mesiodistal distances of the maxillary lateral incisors adjacent to the impacted canines and the correspondent mandibular lateral incisors were measured. The adjacent lateral incisors were classified in: 1 - absent, 2 - small, 3 - peg-shaped, 4 - standard. RESULTS: The results showed that among the patients with impacted canines, there were 21 anomalous teeth (small and peg-shaped and among the control patients there were only three small and peg-shaped teeth, with a statistically significant difference (p = 0.001. No patients were found with impacted canines and absent lateral incisors. CONCLUSION: It was concluded that in patients with anomalous lateral incisors (small and peg-shaped there is a probability to present impacted canines and this must be considered.OBJETIVO: o objetivo foi obter informação sobre a relação existente entre a agenesia e/ou anomalia de forma de incisivos laterais superiores e impacção de caninos. MÉTODOS: foram avaliados 73 pacientes com impacção de caninos e 73 pacientes controle, sem impacção de caninos. Foram medidas as distâncias mesiodistais dos incisivos laterais superiores adjacentes aos caninos impactados e os incisivos laterais correspondentes inferiores. Os incisivos laterais adjacentes foram classificados em: 1 - ausentes; 2 - pequenos; 3 - conoides; 4 - normais. RESULTADOS: os resultados mostraram que no grupo de pacientes com caninos impactados foram encontrados 22 dentes anômalos (pequenos e conoides, e no grupo controle apenas três dentes pequenos e conoides, sendo uma diferença estatisticamente significativa (p=0,001. Não foram encontrados pacientes com canino impactado e incisivo lateral ausente. CONCLUS

  5. Central Nervous System Based Computing Models for Shelf Life Prediction of Soft Mouth Melting Milk Cakes

    Directory of Open Access Journals (Sweden)

    Gyanendra Kumar Goyal

    2012-04-01

    Full Text Available This paper presents the latency and potential of central nervous system based system intelligent computer engineering system for detecting shelf life of soft mouth melting milk cakes stored at 10o C. Soft mouth melting milk cakes are exquisite sweetmeat cuisine made out of heat and acid thickened solidified sweetened milk. In today’s highly competitive market consumers look for good quality food products. Shelf life is a good and accurate indicator to the food quality and safety. To achieve good quality of food products, detection of shelf life is important. Central nervous system based intelligent computing model was developed which detected 19.82 days shelf life, as against 21 days experimental shelf life.

  6. Aesthetic Rehabilitation of a Complicated Crown-Root Fracture of the Maxillary Incisor: Combination of Orthodontic and Implant Treatment

    Directory of Open Access Journals (Sweden)

    Érica Dorigatti de Avila

    2014-01-01

    Full Text Available The aim of this paper is to present a complex rehabilitation, of fractured tooth, with implants in anterior region considering the orthodontics extrusion to clinical success. At 7 years old, the patient fractured the maxillary left central incisor and the dentist did a crown with the fragment. Twenty years later, the patient was referred to a dental clinic for orthodontic treatment, with the chief complaint related to an accentuated deep bite, and a professional started an orthodontic treatment. After sixteen months of orthodontic treatment, tooth 21 fractured. The treatment plan included an orthodontic extrusion of tooth 21 and implant placement. This case has been followed up and the clinical and radiographic examinations show excellence esthetic results and satisfaction of patient. The forced extrusion can be a viable treatment option in the management of crown root fracture of an anterior tooth to gain bone in a vertical direction. This case emphasizes that to achieve the esthetic result a multidisciplinary approach is necessary.

  7. Central Nervous System Based Computing Models for Shelf Life Prediction of Soft Mouth Melting Milk Cakes

    OpenAIRE

    Gyanendra Kumar Goyal; Sumit Goyal

    2012-01-01

    This paper presents the latency and potential of central nervous system based system intelligent computer engineering system for detecting shelf life of soft mouth melting milk cakes stored at 10o C. Soft mouth melting milk cakes are exquisite sweetmeat cuisine made out of heat and acid thickened solidified sweetened milk. In today’s highly competitive market consumers look for good quality food products. Shelf life is a good and accurate indicator to the food quality and safety. To achieve g...

  8. Rural-Urban Transition in Central Java: Population and Economic Structural Changes Based on Cluster Analysis

    OpenAIRE

    Wiwandari Handayani

    2013-01-01

    In Central Java, in addition to the traditional view of urban transition as an aspect of urban industrialization, rural industrialization based on small- to medium-sized enterprises has become a concern, at least since the Indonesian economic crisis in 1997. Combinations of typical urban and rural activities have resulted in certain features of rural-urban transition as the urban population has continued to increase notably. The intention of this paper is to examine how rural-urban transition...

  9. An Agent-Based Model of Centralized Institutions, Social Network Technology, and Revolution

    OpenAIRE

    Makowsky, Michael D.; Jared Rubin

    2011-01-01

    Recent uprisings in the Arab world consist of individuals revealing vastly different preferences than were expressed prior to the uprisings. This paper sheds light on the general mechanisms underlying large-scale social and institutional change. We employ an agent-based model to test the impact of authority centralization and social network technology on preference revelation and falsification, social protest, and institutional change. We find that the amount of social and institutional chang...

  10. Mathematical Modeling of a developed Central Receiver Based on Evacuated Solar Tubes

    OpenAIRE

    Ali Basil. H.; Gilani S. I.; Al-Kayiem Hussain H.

    2016-01-01

    Solar central receiver plays a considerable role in the plant output power; it is one of the most important synthesis in the solar power tower plants. Its performance directly affects the efficiency of the entire solar power generation system. In this study, a new designed receiver model based on evacuated solar tube was proposed, and the dynamic characteristics of the developed receiver were investigated. In order to optimise and evaluate the dynamic characteristics of solar power plant comp...

  11. CrisprGE: a central hub of CRISPR/Cas-based genome editing

    OpenAIRE

    Kaur, Karambir; Tandon, Himani; Gupta, Amit Kumar; Kumar, Manoj

    2015-01-01

    CRISPR system is a powerful defense mechanism in bacteria and archaea to provide immunity against viruses. Recently, this process found a new application in intended targeting of the genomes. CRISPR-mediated genome editing is performed by two main components namely single guide RNA and Cas9 protein. Despite the enormous data generated in this area, there is a dearth of high throughput resource. Therefore, we have developed CrisprGE, a central hub of CRISPR/Cas-based genome editing. Presently,...

  12. Traumatic injuries of the permanent maxillory incisors at dental department, pakistan institute of medical sciences islamabad: A retrospective study

    International Nuclear Information System (INIS)

    The study aims to ascertain the prevalence of traumatic dental injures of the maxillary permanent incisors at Dental Department, Pakistan Institute of Medical Science Islamabad during the years 2003-2005. Information concerning age, sex, cause, type of tooth number of injured teeth and patterns of tooth injury were recorded retrospectively from 33 patients aged between 8-40 years, comprising 498 traumatized teeth. The dental record of all the patients presenting with dental trauma were examined for collection of data relating to age, sex, cause, number of injured teeth, type of tooth and type of tooth trauma. Type of tooth trauma was recorded according to the Andreason classification. The data was subsequently processed and analyzed using the SPSS statistical software programme. The statistical significance level was set at 5%. Of the 336 patients, 227 were males (67.6%) and 109 were female (32.4%). The gender difference was statistically significant (p<0.0001). The patients had a total of 498 traumatized teeth. A large number of dental trauma occurred in patients aged between 9-11 years. Most injuries involved one tooth in 227 patients (67.6%). However two teeth in 90 patients (26.7%), three teeth in 11 patients (3.2%) and only in 8 patients (2.3%) four teeth were involved. Fractures in enamel only occurred in 74 teeth (14.6%). Uncomplicated crown fractures in 208 teeth (41.9%) were the most commonly encountered dental trauma. 137 teeth (27.6%) suffered complicated crown fractures, 44 teeth (8.9%) uncomplicated crown-root fractures, 19 teeth (3.8%) complicated crown-root fractures and avulsion in 16 teeth (3.2%) only. The main causes were falls in 225 patients (66.9%), collision with objects in 40 patients (11.9%), road traffic accident in 31 patients (9.2%) violence in 31 patients (6.2%), and sports in 19 patients (5.6%). The maxillary central incisor was traumatized in 384 teeth showing a high percentage of 77%. Raising public dental awareness regarding the

  13. Development of a Physiologically-Based Pharmacokinetic Model of the Rat Central Nervous System

    Directory of Open Access Journals (Sweden)

    Raj K. Singh Badhan

    2014-03-01

    Full Text Available Central nervous system (CNS drug disposition is dictated by a drug’s physicochemical properties and its ability to permeate physiological barriers. The blood–brain barrier (BBB, blood-cerebrospinal fluid barrier and centrally located drug transporter proteins influence drug disposition within the central nervous system. Attainment of adequate brain-to-plasma and cerebrospinal fluid-to-plasma partitioning is important in determining the efficacy of centrally acting therapeutics. We have developed a physiologically-based pharmacokinetic model of the rat CNS which incorporates brain interstitial fluid (ISF, choroidal epithelial and total cerebrospinal fluid (CSF compartments and accurately predicts CNS pharmacokinetics. The model yielded reasonable predictions of unbound brain-to-plasma partition ratio (Kpuu,brain and CSF:plasma ratio (CSF:Plasmau using a series of in vitro permeability and unbound fraction parameters. When using in vitro permeability data obtained from L-mdr1a cells to estimate rat in vivo permeability, the model successfully predicted, to within 4-fold, Kpuu,brain and CSF:Plasmau for 81.5% of compounds simulated. The model presented allows for simultaneous simulation and analysis of both brain biophase and CSF to accurately predict CNS pharmacokinetics from preclinical drug parameters routinely available during discovery and development pathways.

  14. Decentralized State Estimation Algorithm of Centralized Equivalent Precision for Formation Flying Spacecrafts Based on Junction Tree

    Directory of Open Access Journals (Sweden)

    Mengyuan Dai

    2015-01-01

    Full Text Available As centralized state estimation algorithms for formation flying spacecraft would suffer from high computational burdens when the scale of the formation increases, it is necessary to develop decentralized algorithms. To the state of the art, most decentralized algorithms for formation flying are derived from centralized EKF by simplification and decoupling, rendering suboptimal estimations. In this paper, typical decentralized state estimation algorithms are reviewed, and a new scheme for decentralized algorithms is proposed. In the new solution, the system is modeled as a dynamic Bayesian network (DBN. A probabilistic graphical method named junction tree (JT is used to analyze the hidden distributed structure of the DBNs. Inference on JT is a decentralized form of centralized Bayesian estimation (BE, which is a modularized three-step procedure of receiving messages, collecting evidences, and generating messages. As KF is a special case of BE, the new solution based on JT is equivalent in precision to centralized KF in theory. A cooperative navigation example of a three-satellite formation is used to test the decentralized algorithms. Simulation results indicate that JT has the best precision among all current decentralized algorithms.

  15. 拔除上颌中切牙的正畸治疗分析%Orthodontic treatment with maxillary incisor extraction

    Institute of Scientific and Technical Information of China (English)

    韦溅萍; 马佳君

    2015-01-01

    目的:探讨拔除上颌中切牙进行矫治的疗效和治疗特点。方法:选择拔除上颌中切牙进行矫治的患者9例,男4例、女5例,开始治疗年龄平均17.2岁。拔除双侧上颌中切牙和下颌2颗第一前磨牙者5例;拔除单侧上颌中切牙及对侧第一前磨牙和下颌2颗第一前磨牙者4例。进行治疗前后 Bolton 指数、X 线头影测量和临床疗效分析。结果:所有患者均取得了良好的疗效。治疗前预测 Bolton 指数前牙比和全牙比分别为80.14%和91.31%;治疗后分别为78.68%和90.28%。X 线头影测量分析治疗前后 U1-NA(mm)、U1-NA、L1-NB(mm)、L1-NB、U1-SN、L1-MP、UL-E、LL-E 的值减小(P <0.05)。结论:根据 Bo-lton 指数分析,进行个体化设计,拔除双侧上颌中切牙或单侧上颌中切牙及对侧第一前磨牙和下颌2颗第一前磨牙进行正畸治疗,可以获得良好的疗效。%Objective:To evaluate the effectiveness and treatment feature of maxillary incisor extraction in orthodontics.Methods:9 patients underwent orthodontic treatment with maxillary incisor extraction,5 female and 4 male,with an average age of 1 7.2 years at the start,were included.5 patients were treated by extraction of both upper incisors and lower first premolars,4 by extraction of the abnor-mal incisor and the first premolars in the other three quadrants.Cephalometric and Bolton index analysis were carried out.Results:Sat-isfactory treatment results were observed in all patients.Before treatment the predicted Bolton index of the patients of the anterior ratio and the overall ratio were 80.1 4% and 91 .3%,after orthodontic treatment 78.68% and 90.28%,respectively.Cephalometric analysis showed that U1 -NA(mm),U1 -NA,L1 -NB(mm),L1 -NB,U1 -SN,L1 -MP,UL-E and LL-E were decreased(P <0.05).Conclu-sion:Individual treatment plan based on Bolton index analysis and the corresponding techniques and methods,the patients with abnor

  16. Molar incisor hypomineralization: Considerations about treatment in a controlled longitudinal case

    Directory of Open Access Journals (Sweden)

    Daniela Cristina de Oliveira

    2015-01-01

    Full Text Available Molar incisor hypomineralization (MIH is a defect in the tooth enamel of systemic origin and may affect one or all four first permanent molars frequently associated with the permanent incisors. This case reports a 7-year-old child with severe MIH in the permanent molars associated with tooth decay and intense pain. In the first stage of treatment, therapy was performed with fluoride varnish and restoration with glass ionomer cement (GIC. After 6 years of clinical and radiographic follow-up, the restorations presented wear and fractures on the margins, indicating their replacement with composite resin. Severe cases of MIH in the early permanent molars can be treated with varnish and GIC to restore the patient′s comfort and strengthen the hypomineralized dental structures. The clinical and radiographic monitoring frequently indicated when the restoration with composite resin should be performed.

  17. Unilateral Fusion of Maxillary Lateral Incisor: Diagnosis Using Cone Beam Computed Tomography

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    Iury Oliveira Castro

    2014-01-01

    Full Text Available Objective. The objective of this paper is to report a dental fusion case focusing on clinical and radiographic features for the diagnosis. Method. To report a case of right maxillary lateral incisor fusion and a supernumerary tooth, the anatomy of the root canal and dental united portion were assessed by cone beam computed tomography (CBCT. Results. The clinical examination showed dental juxtaposition with the absence of interdental papilla and esthetic impairment in the right maxillary lateral incisor region. The periapical radiography did not provide enough information for the differential diagnosis due to the inherent limitations of this technique. CBCT confirmed the presence of tooth fusion. Conclusion. CBCT examination supports the diagnosis and provides both the identification of changes in tooth development and the visualization of their extent and limits.

  18. Conservative treatment of shovel-shaped upper incisors and dens invaginatus: a case study

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    Maisa Oliveira Caliani Corral Morales

    2012-01-01

    Full Text Available The purpose of this paper was to describe the conservative treatment adopted in one nonsyndromic patient presenting with shovel-shaped upper incisors and dens invaginatus. A 13-yearold female patient sought treatment reporting pain in response to cold stimuli in the upper anterior teeth. Four upper incisors with shovel-shaped anatomical alterations in the palatal side of the crown were detected during intra-oral clinical examination; in addition, imaging exams revealed a type I dens invaginatus in tooth 22. There was no communication between the carious lesion and the pulp chamber, and a restorative treatment plan was developed. After 2 years of follow-up, the patient showed absence of pain, fi stulas, swelling, or periodontal pockets. When faced with anomalous teeth, conservative procedures should be considered as a potential solution for restorative and endodontic treatment.

  19. Isolation and Culture of Dental Epithelial Stem Cells from the Adult Mouse Incisor

    OpenAIRE

    Chavez, Miquella G.; Hu, Jimmy; SEIDEL, KERSTIN; Li, Chunying; Jheon, Andrew; Naveau, Adrien; Horst, Orapin; Klein, Ophir D.

    2014-01-01

    Understanding the cellular and molecular mechanisms that underlie tooth regeneration and renewal has become a topic of great interest1-4, and the mouse incisor provides a model for these processes. This remarkable organ grows continuously throughout the animal's life and generates all the necessary cell types from active pools of adult stem cells housed in the labial (toward the lip) and lingual (toward the tongue) cervical loop (CL) regions. Only the dental stem cells from the labial CL give...

  20. Sagittal changes in lower incisors by the use of lingual arch

    Directory of Open Access Journals (Sweden)

    Helen Carolina Becker Letti

    2013-06-01

    Full Text Available OBJECTIVE: The objective of this study was to evaluate a sagittal variation on the lower incisors with the use of the lingual arch on the transition from mixed to permanent dentition. METHODS: The sample was constituted of 44 Caucasian patients (26 girls and 18 boys, divided in two groups: CG, control group, monitoring the lower arch space with no orthodontic/orthopedic treatment during the rated period (n = 14; EG, experimental group, presenting anterior inferior mild crowding and installation of the lingual arch for space maintenance (n = 30. The position of the lower incisors was analyzed on computerized cephalometric tracings performed at the beginning of the monitoring (T1 and at the end, on the permanent dentition (T2. In order to evaluate the position of the incisors it was used Tweed and Steiner measurements: IMPA, 1.NB and 1-NB. The alterations were analyzed through the "t" test for paired samples, while the differences between the groups were analyzed through the "t" test for independent samples, as for sexual dimorphism. RESULTS: The values in T2 were greater in relation to T1 for all measurements on EG (IMPA, p = 0.038; 1.NB, p = 0.007 and 1-NB, p < 0.0001. On comparing the differences (T2-T1 between CG and EG, it can be gauged differences significantly superior for measure 1.NB (p = 0.002 and 1-NB (p < 0.0001 on EG. There was no statisticaly significant difference between genres. CONCLUSION: It was concluded that the lower incisors were projected after using the lingual arch to control the space on the transition from mixed to permanent dentition, however, within acceptable standards, not having difference between genres.

  1. Relapse of incisor crowding: A visit to the prince of salina

    OpenAIRE

    López-Areal García, Luis José; Gandía Franco, José Luis

    2012-01-01

    The management of the retention period after comprehensive orthodontic treatment is of great importance, as a primary goal of clinician. Considerable controversy still surrounds the problem of stability after the retention period. Many studies analyze factors associated to the presence of crowding or incisor irregularity and find predictive features on its relapse. Most studies have reported little o no correlation between the treatment changes in the biological parameters - clinical, biometr...

  2. Interproximal wear versus incisors extraction to solve anterior lower crowding: A systematic review

    OpenAIRE

    Natália Valli de Almeida; Giordani Santos Silveira; Daniele Masterson Tavares Pereira; Claudia Trindade Mattos; José Nelson Mucha

    2015-01-01

    OBJECTIVE: To determine by means of a systematic review the best treatment, whether interproximal wear or incisor extraction, to correct anterior lower crowding in Class I patients in permanent dentition. METHODS: A literature review was conducted using MEDLINE, Scopus and Web of Science to retrieve studies published between January 1950 and October 2013. In selecting the sample, the following inclusion criteria were applied: studies involving interproximal wear and/or extraction of mandibula...

  3. The efficacy of centralized flow rate control in 802.11-based wireless mesh networks

    KAUST Repository

    Jamshaid, K.

    2013-06-13

    Commodity WiFi-based wireless mesh networks (WMNs) can be used to provide last mile Internet access. These networks exhibit extreme unfairness with backlogged traffic sources. Current solutions propose distributed source-rate control algorithms requiring link-layer or transport-layer changes on all mesh nodes. This is often infeasible in large practical deployments. In wireline networks, router-assisted rate control techniques have been proposed for use alongside end-to-end mechanisms. We wish to evaluate the feasibility of establishing similar centralized control via gateways in WMNs. In this paper, we focus on the efficacy of this control rather than the specifics of the controller design mechanism. We answer the question: Given sources that react predictably to congestion notification, can we enforce a desired rate allocation through a single centralized controller? The answer is not obvious because flows experience varying contention levels, and transmissions are scheduled by a node using imperfect local knowledge. We find that common router-assisted flow control schemes used in wired networks fail in WMNs because they assume that (1) links are independent, and (2) router queue buildups are sufficient for detecting congestion. We show that non-work-conserving, rate-based centralized scheduling can effectively enforce rate allocation. It can achieve results comparable to source rate limiting, without requiring any modifications to mesh routers or client devices. 2013 Jamshaid et al.; licensee Springer.

  4. Soft Tissue Stability around Single Implants Inserted to Replace Maxillary Lateral Incisors: A 3D Evaluation

    Science.gov (United States)

    Mangano, F. G.; Picciocchi, G.; Park, K. B.

    2016-01-01

    Purpose. To evaluate the soft tissue stability around single implants inserted to replace maxillary lateral incisors, using an innovative 3D method. Methods. We have used reverse-engineering software for the superimposition of 3D surface models of the dentogingival structures, obtained from intraoral scans of the same patients taken at the delivery of the final crown (S1) and 2 years later (S2). The assessment of soft tissues changes was performed via calculation of the Euclidean surface distances between the 3D models, after the superimposition of S2 on S1; colour maps were used for quantification of changes. Results. Twenty patients (8 males, 12 females) were selected, 10 with a failing/nonrestorable lateral incisor (test group: immediate placement in postextraction socket) and 10 with a missing lateral incisor (control group: conventional placement in healed ridge). Each patient received one immediately loaded implant (Anyridge®, Megagen, Gyeongbuk, South Korea). The superimposition of the 3D surface models taken at different times (S2 over S1) revealed a mean (±SD) reduction of 0.057 mm (±0.025) and 0.037 mm (±0.020) for test and control patients, respectively. This difference was not statistically significant (p = 0.069). Conclusions. The superimposition of the 3D surface models revealed an excellent peri-implant soft tissue stability in both groups of patients, with minimal changes registered along time. PMID:27298621

  5. The Multidisciplinary Management of Fused Maxillary Lateral Incisor with a Supernumerary Tooth in Cleft Lip Adolescence

    Directory of Open Access Journals (Sweden)

    Ahmet Yagci

    2014-01-01

    Full Text Available Fusion, an uncommon anomaly of the hard dental tissues, is potentially the cause of clinical problems related to esthetics, tooth spacing, and other periodontal complications. This paper describes a multidisciplinary approach involving surgical, endodontic, restorative, and orthodontic attention for the successful, functional, and esthetic rehabilitation of a maxillary left lateral incisor fused with a supernumerary tooth in unilateral cleft lip adolescence in contralateral side. After clinical and radiographic examinations, a fusion between the left maxillary lateral incisor and a supernumerary tooth was diagnosed in the patient, and a small connection was detected between the pulp systems of the two root canals. The case reported in this paper presents the successful resolution of a fused maxillary lateral incisor with a supernumerary tooth, using endodontic, surgical, restorative, and orthodontic management. The decision made in extracting or retaining the fused tooth depends on the arch discrepancy and esthetic needs. Future studies, with long-term followup, will be helpful in evaluating the long-term efficacy of the different treatment options.

  6. Interproximal wear versus incisors extraction to solve anterior lower crowding: A systematic review

    Directory of Open Access Journals (Sweden)

    Natália Valli de Almeida

    2015-02-01

    Full Text Available OBJECTIVE: To determine by means of a systematic review the best treatment, whether interproximal wear or incisor extraction, to correct anterior lower crowding in Class I patients in permanent dentition. METHODS: A literature review was conducted using MEDLINE, Scopus and Web of Science to retrieve studies published between January 1950 and October 2013. In selecting the sample, the following inclusion criteria were applied: studies involving interproximal wear and/or extraction of mandibular incisors, as well as Class I cases with anterior lower crowding in permanent dentition. RESULTS: Out of a total of 943 articles found after excluding duplicates, 925 were excluded after abstract analysis. After full articles were read, 13 were excluded by the eligibility criteria and one due to methodological quality; therefore, only fours articles remained: two retrospective and two randomized prospective studies. Data were collected, analyzed and organized in tables. CONCLUSION: Both interproximal wear and mandibular incisor extraction are effective in treating Class I malocclusion in permanent dentition with moderate anterior lower crowding and pleasant facial profile. There is scant evidence to determine the best treatment option for each case. Clinical decision should be made on an individual basis by taking into account dental characteristics, crowding, dental and oral health, patient's expectations and the use of set-up models.

  7. Clinical treatment approach of a child with molar incisor hypomineralization (MIH combined with malocclusion.

    Directory of Open Access Journals (Sweden)

    Rossitza Kabaktchieva

    2012-04-01

    Full Text Available Introduction. Molar incisor hypomineralization (MIH was defined as "hypomineralisation of systemic origin of permanent first molars, frequently associated with affected incisors". MIH includes the presence of demarcated opacity, post eruptive enamel breakdown, atypical restoration. Тhe approach to management suggested: risk identification, early diagnosis, remineralization for prevention of caries and post eruption breakdown, restorations. The clinicians very seldom notice that children with MIH usually have both- hypomineralisation and malocclusions, and they do not discuss combine treatment plan.Aim. To present our interdisciplinary approach to a patient with MIH, combined with malocclusion.Material and methods. We are presenting 9 year old child with contusio and fractura coronae dentis noncomplicata, distal occlusion, overjet, overbite and retrusion. Two consecutive stages were defined: First stage:- Professional oral hygiene and local remineralisation therapy- Vital pulp therapy of tooth 21 - Space gaining for restoration of the lost height of the molars by the means of posterior bite-plane removable appliance- Restoration of the molars with metal inlays- Lingual tipping of the lower incisorsSecond stage:- Class II correction- Growth control Results.First phase: - The tooth 21 was restored with aesthetic composite material;- Occlusion was raised with occlusal restorations (inleys and orthodontic appliance. Second phase:Medialisation of mandible and holding maxillary growth with functional appliance and occipital EOA until class one occlusal relations.Conclusion. Children with MIH should be examined and treated complex in collaboration with orthodontist and if necessary by other specialists too.

  8. Central-force decomposition of spline-based modified embedded atom method potential

    Science.gov (United States)

    Winczewski, S.; Dziedzic, J.; Rybicki, J.

    2016-10-01

    Central-force decompositions are fundamental to the calculation of stress fields in atomic systems by means of Hardy stress. We derive expressions for a central-force decomposition of the spline-based modified embedded atom method (s-MEAM) potential. The expressions are subsequently simplified to a form that can be readily used in molecular-dynamics simulations, enabling the calculation of the spatial distribution of stress in systems treated with this novel class of empirical potentials. We briefly discuss the properties of the obtained decomposition and highlight further computational techniques that can be expected to benefit from the results of this work. To demonstrate the practicability of the derived expressions, we apply them to calculate stress fields due to an edge dislocation in bcc Mo, comparing their predictions to those of linear elasticity theory.

  9. Evidence-based measures to prevent central line-associated bloodstream infections: a systematic review 1

    Science.gov (United States)

    Perin, Daniele Cristina; Erdmann, Alacoque Lorenzini; Higashi, Giovana Dorneles Callegaro; Sasso, Grace Teresinha Marcon Dal

    2016-01-01

    ABSTRACT Objective: to identify evidence-based care to prevent CLABSI among adult patients hospitalized in ICUs. Method: systematic review conducted in the following databases: PubMed, Scopus, Cinahl, Web of Science, Lilacs, Bdenf and Cochrane Studies addressing care and maintenance of central venous catheters, published from January 2011 to July 2014 were searched. The 34 studies identified were organized in an instrument and assessed by using the classification provided by the Joanna Briggs Institute. Results: the studies presented care bundles including elements such as hand hygiene and maximal barrier precautions; multidimensional programs and strategies such as impregnated catheters and bandages and the involvement of facilities in and commitment of staff to preventing infections. Conclusions: care bundles coupled with education and the commitment of both staff and institutions is a strategy that can contribute to decreased rates of central line-associated bloodstream infections among adult patients hospitalized in intensive care units. PMID:27598378

  10. Sulcus-based MR analysis of focal cortical dysplasia located in the central region.

    Directory of Open Access Journals (Sweden)

    Pauline Roca

    Full Text Available Focal cortical dysplasias (FCDs are mainly located in the frontal region, with a particular tropism for the central sulcus. Up to 30% of lesions are undetected (magnetic resonance [MR]-negative FCD patients or belatedly diagnosed by visual analysis of MR images. We propose an automated sulcus-based method to analyze abnormal sulcal patterns associated with central FCD, taking into account the normal interindividual sulcal variability.We retrospectively studied 29 right-handed patients with FCD in the central region (including 12 MR negative histologically-confirmed cases and 29 right-handed controls. The analysis of sulcal abnormalities from T1-weighted MR imaging (MRI was performed using a graph-based representation of the cortical folds and an automated sulci recognition system, providing a new quantitative criterion to describe sulcal patterns, termed sulcus energy.Group analysis showed that the central sulcus in the hemisphere ipsilateral to the FCD exhibited an abnormal sulcal pattern compared with controls (p = 0.032. FCDs were associated with abnormal patterns of the central sulci compared with controls (p = 0.006, a result that remained significant when MR-negative and MR-positive patients were considered separately, while the effects of sex, age and MR-field were not significant. At the individual level, sulcus energy alone failed to detect the FCD lesion. We found, however, a significant association between maximum z-scores and the site of FCD (p = 0.0046 which remained significant in MR-negative (p = 0.024 but not in MR-positive patients (p = 0.058. The maximum z-score pointed to an FCD sulcus in four MR-negative and five MR-positive patients.We identified abnormal sulcal patterns in patients with FCD of the central region compared with healthy controls. The abnormal sulcal patterns ipsilateral to the FCD and the link between sulcus energy and the FCD location strengthen the interest of sulcal abnormalities in FCD patients.

  11. Electric protections based in microprocessors in power plants; Protecciones electricas basadas en microprocesadores en centrales generadoras

    Energy Technology Data Exchange (ETDEWEB)

    Libreros, Domitilo; Castanon Jimenez, Jose Ismael [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    This article is centered around the substitution of the conventional electric protections of a power plant in connection type unit for protections based in microprocessors. A general model of conventional protection of a power plant is described and the number of analogic and digital signals that intervene in that model are quantified. A model is setup for power plant protection with microprocessors, analyzing each one of the modules that would form it. Finally, the algorithms to carry on such protection are presented. [Espanol] Este articulo se centra en torno a la sustitucion de las protecciones electricas convencionales de una central generadora en conexion tipo unidad por protecciones basadas en microprocesadores. Se describe el modelo general de proteccion convencional de una central generadora y se cuantifica el numero de senales analogicas y digitales que interviene en dicho modelo. Se propone un modelo para proteccion de centrales generadoras mediante microprocesadores, analizandose cada uno de los modulos que lo conformarian. Finalmente, se presentan los algoritmos para realizar dicha proteccion.

  12. Cluster-based centralized data fusion for tracking maneuvering targets using interacting multiple model algorithm

    Indian Academy of Sciences (India)

    V Vaidehi; K Kalavidya; S Indira Gandhi

    2004-04-01

    The interacting multiple model (IMM) algorithm has proved to be useful in tracking maneuvering targets. Tracking accuracy can be further improved using data fusion. Tracking of multiple targets using multiple sensors and fusing them at a central site using centralized architecture involves communication of large volumes of measurements to a common site. This results in heavy processing requirement at the central site. Moreover, track updates have to be obtained in the fusion centre before the next measurement arrives. For solving this computational complexity, a cluster-based parallel processing solution is presented in this paper. In this scheme, measurements are sent to the data fusion centre where the measurements are partitioned and given to the slave processors in the cluster. The slave processors use the IMM algorithm to get accurate updates of the tracks. The master processor collects the updated tracks and performs data fusion using ‘weight decision approach’. The improvement in the computation time using clusters in the data fusion centre is presented in this paper.

  13. High-order central Hermite WENO schemes: Dimension-by-dimension moment-based reconstructions

    Science.gov (United States)

    Tao, Zhanjing; Li, Fengyan; Qiu, Jianxian

    2016-08-01

    In this paper, a class of high-order central finite volume schemes is proposed for solving one- and two-dimensional hyperbolic conservation laws. Formulated on staggered meshes, the methods involve Hermite WENO (HWENO) spatial reconstructions, and Lax-Wendroff type discretizations or the natural continuous extension of Runge-Kutta methods in time. Differently from the central Hermite WENO methods we developed previously in Tao et al. (2015) [34], the spatial reconstructions, a core ingredient of the methods, are based on the zeroth-order and the first-order moments of the solution, and are implemented through a dimension-by-dimension strategy when the spatial dimension is higher than one. This leads to much simpler implementation of the methods in higher dimension and better cost efficiency. Meanwhile, the proposed methods have the attractive features of the general central Hermite WENO methods such as being compact in reconstruction and requiring neither flux splitting nor numerical fluxes, while being accurate and essentially non-oscillatory. A collection of one- and two-dimensional numerical examples is presented to demonstrate high resolution and robustness of the methods in capturing smooth and non-smooth solutions.

  14. SOTER-based soil parameter estimates for Central Africa - DR of Congo, Burundi and Rwanda (ver. 1.0)

    NARCIS (Netherlands)

    Batjes, N.H.

    2014-01-01

    This harmonized set of soil parameter estimates for Central Africa, comprising Burundi, the Democratic Republic of the Congo and Rwanda, was derived from the Soil and Terrain Database for Central Africa (SOTERCAF ver. 1.0) and the ISRIC-WISE soil profile database, using standardized taxonomy-based p

  15. Palaeocology of coal-bearing Eocene sediments in central Anatolia (Turkey) based on quantitative palynological data

    Energy Technology Data Exchange (ETDEWEB)

    Akkiraz, M.S.; Kayseri, M.S.; Akgun, F. [Dokuz Eylul University, Izmir (Turkey). Dept. of Geological Engineering

    2008-04-15

    In this study, the lignite-bearing Yoncali formation between Yozgat and Sorgun, in central Anatolia has been palynologically examined. Based on 37 outcrop samples, quantitative palynological studies recognized 64 genera and 136 palynoflora species in the palynological assemblage, which indicated a Middle-Late Eocene age. This paper also presents a quantitative palaeovegetation and palaeoclimate reconstruction for the Middle-Upper Eocene coal occurrences of Central Anatolia on the basis of palynomorph assemblages. The diversified floral and ecological characteristics of the pollen taxa indicates that the Middle-Upper Eocene formations in central Anatolia were characterized by the presence of a complex mangrove swamp with contributions by Nypa, Pelliciera, Avicennia, Diporites tszkaszentgydrgyi and dinoflagellate cysts which reflect warm climatic conditions. Lowland-riparian and montane elements are characterized by the dominance of Myricaceae, Symplocaceae, Icacinaceae, Quercus, Pinus and Castanea. Swamp-freshwater elements are represented by Sparganjaceae, Nymphaceae, Taxodjaceae, Cupressaceae and Nyssa as well as fern spores such as Osmundaceae and Gleicheniaceae. The calculations were performed with the help of the 'Coexistence Approach' method to climatically evaluate palynoflora from the Yozgat-Sorgun area. The obtained results have been compared to data derived from the application of the Coexistence Approach to other, already published Central Anatolian palynofloras of the same age. The results of the climatic inferences suggest that the palaeoclimatic conditions were in the megathermal zone, megatherm/mesotherm intermediate zone whereas mesothermic conditions prevailed in the montane region. Likewise, the results of mean annual range of temperatures indicate the influence of the Indian ocean, which enabled the development of the mangroves.

  16. Modeling infection transmission in primate networks to predict centrality-based risk.

    Science.gov (United States)

    Romano, Valéria; Duboscq, Julie; Sarabian, Cécile; Thomas, Elodie; Sueur, Cédric; MacIntosh, Andrew J J

    2016-07-01

    Social structure can theoretically regulate disease risk by mediating exposure to pathogens via social proximity and contact. Investigating the role of central individuals within a network may help predict infectious agent transmission as well as implement disease control strategies, but little is known about such dynamics in real primate networks. We combined social network analysis and a modeling approach to better understand transmission of a theoretical infectious agent in wild Japanese macaques, highly social animals which form extended but highly differentiated social networks. We collected focal data from adult females living on the islands of Koshima and Yakushima, Japan. Individual identities as well as grooming networks were included in a Markov graph-based simulation. In this model, the probability that an individual will transmit an infectious agent depends on the strength of its relationships with other group members. Similarly, its probability of being infected depends on its relationships with already infected group members. We correlated: (i) the percentage of subjects infected during a latency-constrained epidemic; (ii) the mean latency to complete transmission; (iii) the probability that an individual is infected first among all group members; and (iv) each individual's mean rank in the chain of transmission with different individual network centralities (eigenvector, strength, betweenness). Our results support the hypothesis that more central individuals transmit infections in a shorter amount of time and to more subjects but also become infected more quickly than less central individuals. However, we also observed that the spread of infectious agents on the Yakushima network did not always differ from expectations of spread on random networks. Generalizations about the importance of observed social networks in pathogen flow should thus be made with caution, since individual characteristics in some real world networks appear less relevant than

  17. Structural analysis of the central Columbia Plateau utilizing radar, digital topography, and magnetic data bases

    International Nuclear Information System (INIS)

    Interest in the Hanford site (Washington) as a nuclear production, power, and waste disposal site has led to generation of a vast quantity of geophysical and remote sensing data sets of the central Columbia Plateau. To data, these various studies, including at least 13 independent magnetic linear and image lineament studies, have not been adequately correlated. Therefore, these studies provide a unique opportunity to compare and contrast the viability of the different geophysical and remote sensing techniques. The geology of the central Columbia Plateau is characterized by subdued topography and limited outcrop, with most of the exposure concentrated in localized folded/faulted mountains (the Yakima folds) and along river canyons. In order to efficiently compare lineament data bases, we have written an automated computer routine that correlated lineaments that are within a user specified distance of each other. The angle between their trends has to be less than an input maximum separation angle. If more than two lineament maps exist for the area, the analyst may also specify the minimum number of times each structure must be seen. The lineament correlation routine was applied to data bases of all aeromagnetic linears as well as lineaments seen on radar and a digital elevation model DEM image. Geologic structures align with a set of three-dimensional planar structures identified with our Geologic Spatial Analysis (GSA) system. The GSA analysis is based upon computer automated detection of valley bottoms as defined by a DEM

  18. IMPLEMENTATION OF CENTRAL QUEUE BASED REALTIME SCHEDULER FOR MULTIPLE SOURCE DATA STREAMING

    Directory of Open Access Journals (Sweden)

    V. Kaviha

    2014-01-01

    Full Text Available Real-time data packet sources are required to remain robust against different security threats. This study proposes a real-time secure scheduling strategy for data transmission to enhance the communication throughput and reduce the overheads. The proposed system combines real-time scheduling with security service enhancement, error detection and realtime scheduler based on EDF algorithm using uc/os-II real time operating system, implemented on cortex M3 processor. The scheduling unit uses central queue management model and the security enhancement scheme adopts a blowfish encryption mechanism.

  19. Central FPGA-based destination and load control in the LHCb MHz event readout

    Science.gov (United States)

    Jacobsson, R.

    2012-10-01

    The readout strategy of the LHCb experiment is based on complete event readout at 1 MHz. A set of 320 sub-detector readout boards transmit event fragments at total rate of 24.6 MHz at a bandwidth usage of up to 70 GB/s over a commercial switching network based on Gigabit Ethernet to a distributed event building and high-level trigger processing farm with 1470 individual multi-core computer nodes. In the original specifications, the readout was based on a pure push protocol. This paper describes the proposal, implementation, and experience of a non-conventional mixture of a push and a pull protocol, akin to credit-based flow control. An FPGA-based central master module, partly operating at the LHC bunch clock frequency of 40.08 MHz and partly at a double clock speed, is in charge of the entire trigger and readout control from the front-end electronics up to the high-level trigger farm. One FPGA is dedicated to controlling the event fragment packing in the readout boards, the assignment of the farm node destination for each event, and controls the farm load based on an asynchronous pull mechanism from each farm node. This dynamic readout scheme relies on generic event requests and the concept of node credit allowing load control and trigger rate regulation as a function of the global farm load. It also allows the vital task of fast central monitoring and automatic recovery in-flight of failing nodes while maintaining dead-time and event loss at a minimum. This paper demonstrates the strength and suitability of implementing this real-time task for a very large distributed system in an FPGA where no random delays are introduced, and where extreme reliability and accurate event accounting are fundamental requirements. It was in use during the entire commissioning phase of LHCb and has been in faultless operation during the first two years of physics luminosity data taking.

  20. Systematic review of changes in maxillary incisor exposure and upper lip position with Le Fort I type osteotomies with or without cinch sutures and/or VY closures.

    Science.gov (United States)

    Khamashta-Ledezma, L; Naini, F B

    2014-01-01

    The aim was to systematically review the maxillary incisor exposure and upper lip position changes with Le Fort I type osteotomies for advancement ± impaction with rigid internal fixation, taking into account the use of cinch sutures and VY closures. Electronic databases (Cochrane Library, Medline, Embase, and Web of Science) were searched using medical subject headings (MeSH), key words, truncations, and Boolean operators. Hand searching was also undertaken. Of 979 articles identified, 15 were included (11 retrospective, two prospective, and two unspecified). Relevant study details and outcomes were recorded on a spreadsheet, along with an assessment of their quality. In total, these studies assessed 419 patients (266 female, 118 male) with a mean age of 26.4 years (range 14-57 years). Soft tissue changes were assessed on lateral cephalometric radiographs. The mean maxillary hard tissue advancement and impaction ranged between 0.94 and 8.77 mm and -0.56 and 4.2 mm, respectively. The ranges of ratios demonstrated that from pronasale (0.24-0.35) to labrale superius (0.36-1.43), the soft tissues followed the underlying horizontal hard tissue movement increasingly more closely. Alar base cinch sutures and VY closures tended to increase these ratios. The soft tissue response was more variable vertically. None of the studies reported on maxillary incisor exposure change. More good quality prospective studies are needed. PMID:24103543

  1. A PEG Construction of LDPC Codes Based on the Betweenness Centrality Metric

    Directory of Open Access Journals (Sweden)

    BHURTAH-SEEWOOSUNGKUR, I.

    2016-05-01

    Full Text Available Progressive Edge Growth (PEG constructions are usually based on optimizing the distance metric by using various methods. In this work however, the distance metric is replaced by a different one, namely the betweenness centrality metric, which was shown to enhance routing performance in wireless mesh networks. A new type of PEG construction for Low-Density Parity-Check (LDPC codes is introduced based on the betweenness centrality metric borrowed from social networks terminology given that the bipartite graph describing the LDPC is analogous to a network of nodes. The algorithm is very efficient in filling edges on the bipartite graph by adding its connections in an edge-by-edge manner. The smallest graph size the new code could construct surpasses those obtained from a modified PEG algorithm - the RandPEG algorithm. To the best of the authors' knowledge, this paper produces the best regular LDPC column-weight two graphs. In addition, the technique proves to be competitive in terms of error-correcting performance. When compared to MacKay, PEG and other recent modified-PEG codes, the algorithm gives better performance over high SNR due to its particular edge and local graph properties.

  2. A Site-Specific Index Based on Weathering Forms Visible in Central Oxford, UK

    Directory of Open Access Journals (Sweden)

    Mary J. Thornbush

    2012-11-01

    Full Text Available The authenticity of much of the stone-work along Queen’s Lane in central Oxford, UK presented an opportunity to produce a photographic survey from which a weathering index could be established. This represents a site-specific approach to devising a weathering form. Because it is photo-based, weathering forms are visible for comparison and classification purposes across disciplines. Limestone pertaining to building ashlar and plinths along this roadway, which mainly belong to Queen’s College, St Edmund Hall, New College, and Hertford College, was classified according to this newly introduced weathering index, the size-extent (S-E index, through consideration of type, size, extent, impact, and trigger. This size- (range and extent-based classification system enables for the assessment of weathering forms of various types, including soiling and decay features as well as those potentially expected in the presence of vegetation and animals. Weathering forms of a range of sizes were present, with a slightly greater abundance of small types (mm-cm in the micro- to mesoscale and more discrete types with a low extent. For this location in central Oxford, chemical weathering was found to be the predominant type of soiling and decay.

  3. An application-layer based centralized information access control for VPN

    Institute of Scientific and Technical Information of China (English)

    OUYANG Kai; ZHOU Jing-li; XIA Tao; YU Sheng-sheng

    2006-01-01

    With the rapid development of Virtual Private Network (VPN), many companies and organizations use VPN to implement their private communication. Traditionally, VPN uses security protocols to protect the confidentiality of data, the message integrity and the endpoint authentication. One core technique of VPN is tunneling, by which clients can access the internal servers traversing VPN. However, the tunneling technique also introduces a concealed security hole. It is possible that ifone vicious user can establish tunneling by the VPN server, he can compromise the internal servers behind the VPN server. So this paper presents a novel Application-layer based Centralized Information Access Control (ACIAC) for VPN to solve this problem.To implement an efficient, flexible and multi-decision access control model, we present two key techniques to ACIAC-the centralized management mechanism and the stream-based access control. Firstly, we implement the information center and the constraints/events center for ACIAC. By the two centers, we can provide an abstract access control mechanism, and the material access control can be decided dynamically by the ACIAC's constraint/event mechanism. Then we logically classify the VPN communication traffic into the access stream and the data stream so that we can tightly couple the features of VPN communication with the access control model. We also provide the design of our ACIAC prototype in this paper.

  4. A Combination of Central Pattern Generator-based and Reflex-based Neural Networks for Dynamic, Adaptive, Robust Bipedal Locomotion

    DEFF Research Database (Denmark)

    Di Canio, Giuliano; Larsen, Jørgen Christian; Wörgötter, Florentin;

    2016-01-01

    the interaction of these systems, implementations with reflexbased or central pattern generator (CPG)-based controllers have been tested on bipedal robot systems. In this paper we will combine the two controller types, into a controller that works with both reflex and CPG signals. We use a reflex-based neural......Robotic systems inspired from humans have always been lightening up the curiosity of engineers and scientists. Of many challenges, human locomotion is a very difficult one where a number of different systems needs to interact in order to generate a correct and balanced pattern. To simulate...... network to generate basic walking patterns of a dynamic bipedal walking robot (DACBOT) and then a CPG-based neural network to ensure robust walking behavior...

  5. A Centralized Energy Efficient Distance Based Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Rohit D. Gawade

    2016-01-01

    Full Text Available Wireless sensor network (WSN typically consists of a large number of low cost wireless sensor nodes which collect and send various messages to a base station (BS. WSN nodes are small battery powered devices having limited energy resources. Replacement of such energy resources is not easy for thousands of nodes as they are inaccessible to users after their deployment. This generates a requirement of energy efficient routing protocol for increasing network lifetime while minimizing energy consumption. Low Energy Adaptive Clustering Hierarchy (LEACH is a widely used classic clustering algorithm in WSNs. In this paper, we propose a Centralized Energy Efficient Distance (CEED based routing protocol to evenly distribute energy dissipation among all sensor nodes. We calculate optimum number of cluster heads based on LEACH’s energy dissipation model. We propose a distributed cluster head selection algorithm based on dissipated energy of a node and its distance to BS. Moreover, we extend our protocol by multihop routing scheme to reduce energy dissipated by nodes located far away from base station. The performance of CEED is compared with other protocols such as LEACH and LEACH with Distance Based Thresholds (LEACH-DT. Simulation results show that CEED is more energy efficient as compared to other protocols. Also it improves the network lifetime and stability period over the other protocols.

  6. Accurate stress analysis on rigid central buckle of long-span suspension bridges based on submodel method

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Runyang Suspension Bridge (RSB) with the main span of 1490 m is the longest bridge in China and the third longest one in the world. In this bridge the rigid central buckle is employed for the first time in the mid-span of the suspension bridge in China. For such a super-long-span bridge, the traditional finite element (FE) modeling technique and stress analysis methods obviously cannot satisfy the needs of conducting accurate stress analysis on the central buckle. In this paper, the submodel method is in- troduced and for the first time used in analyzing the stresses of the central buckle. After an accurate FE submodel of the central buckle was specially established according to the analysis results from the whole FE model, the connection technique between the two-scale FE models was realized and the ac- curate stresses of the central buckle under various vehicle load cases were then conducted based on the submodel method. The calculation results were testified to be accurate and reliable by the field measurements, which show the efficiency and reliability of the submodel method on analyzing the mechanical condition of the central buckle of long-span suspension bridges. Finally, the working be- havior and mechanical characteristics of the central buckle of the RSB under vehicle loads were ana- lyzed based on the calculation and measurement results. The results obtained in this paper can provide theoretic references for analyzing and designing the rigid central buckle in long-span suspension bridges in future.

  7. Central FPGA-based Destination and Load Control in the LHCb MHz Event Readout

    CERN Document Server

    Jacobsson, Richard

    2012-01-01

    The readout strategy of the LHCb experiment [1] is based on complete event readout at 1 MHz [2]. Over 300 sub-detector readout boards transmit event fragments at 1 MHz over a commercial 70 Gigabyte/s switching network to a distributed event building and trigger processing farm with 1470 individual multi-core computer nodes [3]. In the original specifications, the readout was based on a pure push protocol. This paper describes the proposal, implementation, and experience of a powerful non-conventional mixture of a push and a pull protocol, akin to credit-based flow control. A high-speed FPGA-based central master module controls the event fragment packing in the readout boards, the assignment of the farm node destination for each event, and controls the farm load based on an asynchronous pull mechanism from each farm node. This dynamic readout scheme relies on generic event requests and the concept of node credit allowing load balancing and trigger rate regulation as a function of the global farm load. It also ...

  8. Eruptive malpositioning of the mandibular permanent lateral incisors: three case reports.

    Science.gov (United States)

    Bradley, E J; Bell, R A

    1990-01-01

    Ectopic eruption of the mandibular permanent lateral incisors involving the loss of the adjacent primary canines is not uncommon, yet the extreme distalization and transposition of such teeth (partial or true) has been reported infrequently. Three cases that illustrate various anomalous eruption-exfoliation patterns are presented. Theories that attempt to explain the etiology of anomalous eruption positions are discussed. However, the multifactorial process of growth and development makes it difficult to identify specific primary etiological factors. Treatment options also are discussed and illustrated, with emphasis on early orthodontic intervention for optimal results.

  9. Skeletal class III camouflage by mandibular incisor extraction: A case report

    Directory of Open Access Journals (Sweden)

    Janardhanan Kumaresan

    2014-01-01

    Full Text Available Treatment planning in orthodontics plays a key role in determining the successful treatment of any kind of malocclusion. Skeletal class III malocclusions are generally difficult to treat because of the complex nature of the skeletal and dental manifestations they produce. Mild to moderate skeletal class III malocclusions sometimes have an acceptable facial profile where orthodontic camouflage is possible. In this case report, camouflage of a mild skeletal class III is done by the extraction of a single mandibular incisor, which helped in maintaining the profile of the patient and also in the correction of crowding in the mandibular anterior region.

  10. Branch-based centralized data collection for smart grids using wireless sensor networks.

    Science.gov (United States)

    Kim, Kwangsoo; Jin, Seong-il

    2015-05-21

    A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network constructs into several branches. A conflict-free query schedule is generated based on the branches. Each power usage is collected according to the schedule. The proposed method has important features: shortening query processing time and avoiding collisions between a query and query responses. We evaluate this method using the ns-2 simulator. The experimental results show that this method can achieve both collision avoidance and fast query processing at the same time. The success rate of data collection at a sink node executing this method is 100%. Its running time is about 35 percent faster than that of the round-robin method, and its memory size is reduced to about 10% of that of the depth-first search method.

  11. Branch-based centralized data collection for smart grids using wireless sensor networks.

    Science.gov (United States)

    Kim, Kwangsoo; Jin, Seong-il

    2015-01-01

    A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network constructs into several branches. A conflict-free query schedule is generated based on the branches. Each power usage is collected according to the schedule. The proposed method has important features: shortening query processing time and avoiding collisions between a query and query responses. We evaluate this method using the ns-2 simulator. The experimental results show that this method can achieve both collision avoidance and fast query processing at the same time. The success rate of data collection at a sink node executing this method is 100%. Its running time is about 35 percent faster than that of the round-robin method, and its memory size is reduced to about 10% of that of the depth-first search method. PMID:26007734

  12. Branch-Based Centralized Data Collection for Smart Grids Using Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kwangsoo Kim

    2015-05-01

    Full Text Available A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network constructs into several branches. A conflict-free query schedule is generated based on the branches. Each power usage is collected according to the schedule. The proposed method has important features: shortening query processing time and avoiding collisions between a query and query responses. We evaluate this method using the ns-2 simulator. The experimental results show that this method can achieve both collision avoidance and fast query processing at the same time. The success rate of data collection at a sink node executing this method is 100%. Its running time is about 35 percent faster than that of the round-robin method, and its memory size is reduced to about 10% of that of the depth-first search method.

  13. Separating temporal and topological effects in walk-based network centrality

    Science.gov (United States)

    Colman, Ewan R.; Charlton, Nathaniel

    2016-07-01

    The recently introduced concept of dynamic communicability is a valuable tool for ranking the importance of nodes in a temporal network. Two metrics, broadcast score and receive score, were introduced to measure the centrality of a node with respect to a model of contagion based on time-respecting walks. This article examines the temporal and structural factors influencing these metrics by considering a versatile stochastic temporal network model. We analytically derive formulas to accurately predict the expectation of the broadcast and receive scores when one or more columns in a temporal edge-list are shuffled. These methods are then applied to two publicly available data sets and we quantify how much the centrality of each individual depends on structural or temporal influences. From our analysis, we highlight two practical contributions: a way to control for temporal variation when computing dynamic communicability and the conclusion that the broadcast and receive scores can, under a range of circumstances, be replaced by the row and column sums of the matrix exponential of a weighted adjacency matrix given by the data.

  14. Quantitative study on pollen-based reconstructions of vegetation history from central Canada

    Institute of Scientific and Technical Information of China (English)

    YU Ge; HART Catherina; VETTER Mary; SAUCHYN David

    2008-01-01

    Based on high-resolution pollen records from lake cores in central Canada, the present study instructed pollen taxa assignations in ecosystem groups and modern analogue technique, reported major results of quantitative reconstructions of vegetation history during the last 1000 years, and discussed the validation of simulated vegetation. The results showed that in central America (115°-95°W,40°-60°N), best analogue of the modern vegetation is 81% for boreal forest, 72% for parkland, and 94% for grassland-parkland, which are consistent with vegetation distributions of the North American Ecosystem Ⅱ. Simulations of the past vegetation from the sedimentary pollen showed climate changes during the past 1000 years: it was warm and dry in the Medieval Warm period, cold and wet in the earlier period and cold and dry in the later period of the Little Ice Age. It became obviously increasing warm and drought in the 20th century. The present studies would provide us scientific basis to understand vegetation and climate changes during the last 1000 years in a characteristic region and in 10-100 year time scales.

  15. Quantitative study on pollen-based reconstructions of vegetation history from central Canada

    Institute of Scientific and Technical Information of China (English)

    HART; Catherina; VETTER; Mary; SAUCHYN; David

    2008-01-01

    Based on high-resolution pollen records from lake cores in central Canada, the present study instructed pollen taxa assignations in ecosystem groups and modern analogue technique, reported major results of quantitative reconstructions of vegetation history during the last 1000 years, and discussed the validation of simulated vegetation. The results showed that in central America (115°-95°W, 40°-60°N), best analogue of the modern vegetation is 81% for boreal forest, 72% for parkland, and 94% for grassland-parkland, which are consistent with vegetation distributions of the North American Ecosystem II. Simulations of the past vegetation from the sedimentary pollen showed climate changes during the past 1000 years: it was warm and dry in the Medieval Warm period, cold and wet in the earlier period and cold and dry in the later period of the Little Ice Age. It became obviously increasing warm and drought in the 20th century. The present studies would provide us scientific basis to understand vegetation and climate changes during the last 1000 years in a characteristic region and in 10-100 year time scales.

  16. Efficient crop type mapping based on remote sensing in the Central Valley, California

    Science.gov (United States)

    Zhong, Liheng

    Most agricultural systems in California's Central Valley are purposely flexible and intentionally designed to meet the demands of dynamic markets. Agricultural land use is also impacted by climate change and urban development. As a result, crops change annually and semiannually, which makes estimating agricultural water use difficult, especially given the existing method by which agricultural land use is identified and mapped. A minor portion of agricultural land is surveyed annually for land-use type, and every 5 to 8 years the entire valley is completely evaluated. So far no effort has been made to effectively and efficiently identify specific crop types on an annual basis in this area. The potential of satellite imagery to map agricultural land cover and estimate water usage in the Central Valley is explored. Efforts are made to minimize the cost and reduce the time of production during the mapping process. The land use change analysis shows that a remote sensing based mapping method is the only means to map the frequent change of major crop types. The traditional maximum likelihood classification approach is first utilized to map crop types to test the classification capacity of existing algorithms. High accuracy is achieved with sufficient ground truth data for training, and crop maps of moderate quality can be timely produced to facilitate a near-real-time water use estimate. However, the large set of ground truth data required by this method results in high costs in data collection. It is difficult to reduce the cost because a trained classification algorithm is not transferable between different years or different regions. A phenology based classification (PBC) approach is developed which extracts phenological metrics from annual vegetation index profiles and identifies crop types based on these metrics using decision trees. According to the comparison with traditional maximum likelihood classification, this phenology-based approach shows great advantages

  17. Fractal Systems of Central Places Based on Intermittency of Space-filling

    CERN Document Server

    Chen, Yanguang

    2011-01-01

    The central place models are fundamentally important in theoretical geography and city planning theory. The texture and structure of central place networks have been demonstrated to be self-similar in both theoretical and empirical studies. However, the underlying rationale of central place fractals in the real world has not yet been revealed so far. This paper is devoted to illustrating the mechanisms by which the fractal patterns can be generated from central place systems. The structural dimension of the traditional central place models is d=2 indicating no intermittency in the spatial distribution of human settlements. This dimension value is inconsistent with empirical observations. Substituting the complete space filling with the incomplete space filling, we can obtain central place models with fractional dimension Dcentral place models are converted into fractal central place models. If we further integrate the chance factors into the i...

  18. LexRank: Graph-based Lexical Centrality as Salience in Text Summarization

    CERN Document Server

    Erkan, G; 10.1613/jair.1523

    2011-01-01

    We introduce a stochastic graph-based method for computing relative importance of textual units for Natural Language Processing. We test the technique on the problem of Text Summarization (TS). Extractive TS relies on the concept of sentence salience to identify the most important sentences in a document or set of documents. Salience is typically defined in terms of the presence of particular important words or in terms of similarity to a centroid pseudo-sentence. We consider a new approach, LexRank, for computing sentence importance based on the concept of eigenvector centrality in a graph representation of sentences. In this model, a connectivity matrix based on intra-sentence cosine similarity is used as the adjacency matrix of the graph representation of sentences. Our system, based on LexRank ranked in first place in more than one task in the recent DUC 2004 evaluation. In this paper we present a detailed analysis of our approach and apply it to a larger data set including data from earlier DUC evaluatio...

  19. Distortion-Invariant Binary Image Recognition Based on Central Projection Correlation

    Institute of Scientific and Technical Information of China (English)

    WU Yaming; XIAO Yanping; SUN Fanghong; FANG Nian

    2001-01-01

    A method of central projection correlation which is invariant to distortion of shift, scale and rotation of the binary target image is proposed. A 2-D binary image is transformed into an 1-D central projection referring to the centroid of the binary image. The distortion-invariant central projection correlation is successfully performed by computer simulations and its optical implementation is presented.

  20. SOTER-based soil parameter estimates for Central and Eastern Europe (ver. 2.0)

    NARCIS (Netherlands)

    Batjes, N.H.

    2005-01-01

    This harmonized set of soil parameter estimates for Central and Eastern Europe has been derived from a revised version of the 1:2.5M Soil and Terrain (SOTER) Database for Central and Eastern Europe (SOVEUR ver. 1.1) and the ISRIC-WISE soil profile database. The land surface of Central and Eastern Eu

  1. Situational Lightning Climatologies for Central Florida: Phase IV: Central Florida Flow Regime Based Climatologies of Lightning Probabilities

    Science.gov (United States)

    Bauman, William H., III

    2009-01-01

    The threat of lightning is a daily concern during the warm season in Florida. Research has revealed distinct spatial and temporal distributions of lightning occurrence that are strongly influenced by large-scale atmospheric flow regimes. Previously, the Applied Meteorology Unit (AMU) calculated the gridded lightning climatologies based on seven flow regimes over Florida for 1-, 3- and 6-hr intervals in 5-, 10-, 20-, and 30-NM diameter range rings around the Shuttle Landing Facility (SLF) and eight other airfields in the National Weather Service in Melbourne (NWS MLB) county warning area (CWA). In this update to the work, the AMU recalculated the lightning climatologies for using individual lightning strike data to improve the accuracy of the climatologies. The AMU included all data regardless of flow regime as one of the stratifications, added monthly stratifications, added three years of data to the period of record and used modified flow regimes based work from the AMU's Objective Lightning Probability Forecast Tool, Phase II. The AMU made changes so the 5- and 10-NM radius range rings are consistent with the aviation forecast requirements at NWS MLB, while the 20- and 30-NM radius range rings at the SLF assist the Spaceflight Meteorology Group in making forecasts for weather Flight Rule violations during Shuttle landings. The AMU also updated the graphical user interface with the new data.

  2. Phylogenetic analysis of Persian Gazella, Gazella subgutturosa (Artiodactyla: Bovidae based on cytochrome b in central Iran

    Directory of Open Access Journals (Sweden)

    Davoud Fadakar

    2013-12-01

    Full Text Available Persian gazelle, Gazella subgutturosa, exists throughout arid and semiarid regions of Iran and has a key role in these frail ecosystems. Habitat degradation and population decline has placed it on the list of vulnerable species in 2008. The phylogenetic relationships of three Persian gazelle populations in the central part of Iran (i.e. Ghamishlou National Park and Wildlife Refuge, Mouteh Wildlife Refuge in Isfahan province and Kalmand-Bahadoran Protected Area in Yazd province were investigated using parts and short fragments of mitochondrial cytochrome b gene (425 base pairs. A maximum likelihood phylogenetic tree separated the populations of Yazd and Isfahan provinces, but populations within the Isfahan province shared the same clade. All populations were classified as Persian gazelle. The studied populations are facing threats because of road construction, industrial development and urbanization. Accordingly urgent conservation plans are needed to preserve their genetic diversity and prevent them from falling into extinction.

  3. Village-based primary health care in the Central Highlands of Vietnam.

    Science.gov (United States)

    Barrett, B; Ladinsky, J; Volk, N

    2001-02-01

    This paper describes the first year of an ongoing village health care and economic development project in the Krong Buk district of Dak Lak province in Vietnam's Central Highlands. The project serves 21 villages with a total population of just over 15,000. Most belong to ethnic minority groups. Physicians from the province capital of Boun Me Thuot were trained by a multi-disciplinary team of American health care workers to be trainers and supervisors of 21 village health care workers (VHWs). Two months later, a VHW from each village was trained in primary and preventive health care by the physician-supervisors. Since this initial training, each VHW has been provided with materials, medicines and monthly supervision by the physician-supervisors. The health care component has been complemented by an economic development project based on a system of small loans. Data from the first year of monthly reports and from a baseline survey are presented in this paper.

  4. Satellite-based detection of volcanic sulphur dioxide from recent eruptions in Central and South America

    Directory of Open Access Journals (Sweden)

    D. Loyola

    2008-01-01

    Full Text Available Volcanic eruptions can emit large amounts of rock fragments and fine particles (ash into the atmosphere, as well as several gases, including sulphur dioxide (SO2. These ejecta and emissions are a major natural hazard, not only to the local population, but also to the infrastructure in the vicinity of volcanoes and to aviation. Here, we describe a methodology to retrieve quantitative information about volcanic SO2 plumes from satellite-borne measurements in the UV/Visible spectral range. The combination of a satellite-based SO2 detection scheme and a state-of-the-art 3D trajectory model enables us to confirm the volcanic origin of trace gas signals and to estimate the plume height and the effective emission height. This is demonstrated by case-studies for four selected volcanic eruptions in South and Central America, using the GOME, SCIAMACHY and GOME-2 instruments.

  5. Measuring long-term impact based on network centrality: unraveling cinematic citations.

    Directory of Open Access Journals (Sweden)

    Andreas Spitz

    Full Text Available Traditional measures of success for film, such as box-office revenue and critical acclaim, lack the ability to quantify long-lasting impact and depend on factors that are largely external to the craft itself. With the growing number of films that are being created and large-scale data becoming available through crowd-sourced online platforms, an endogenous measure of success that is not reliant on manual appraisal is of increasing importance. In this article we propose such a ranking method based on a combination of centrality indices. We apply the method to a network that contains several types of citations between more than 40,000 international feature films. From this network we derive a list of milestone films, which can be considered to constitute the foundations of cinema. In a comparison to various existing lists of 'greatest' films, such as personal favourite lists, voting lists, lists of individual experts, and lists deduced from expert polls, the selection of milestone films is more diverse in terms of genres, actors, and main creators. Our results shed light on the potential of a systematic quantitative investigation based on cinematic influences in identifying the most inspiring creations in world cinema. In a broader perspective, we introduce a novel research question to large-scale citation analysis, one of the most intriguing topics that have been at the forefront of scientific enquiries for the past fifty years and have led to the development of various network analytic methods. In doing so, we transfer widely studied approaches from citation analysis to the the newly emerging field of quantification efforts in the arts. The specific contribution of this paper consists in modelling the multidimensional cinematic references as a growing multiplex network and in developing a methodology for the identification of central films in this network.

  6. Measuring long-term impact based on network centrality: unraveling cinematic citations.

    Science.gov (United States)

    Spitz, Andreas; Horvát, Emőke-Ágnes

    2014-01-01

    Traditional measures of success for film, such as box-office revenue and critical acclaim, lack the ability to quantify long-lasting impact and depend on factors that are largely external to the craft itself. With the growing number of films that are being created and large-scale data becoming available through crowd-sourced online platforms, an endogenous measure of success that is not reliant on manual appraisal is of increasing importance. In this article we propose such a ranking method based on a combination of centrality indices. We apply the method to a network that contains several types of citations between more than 40,000 international feature films. From this network we derive a list of milestone films, which can be considered to constitute the foundations of cinema. In a comparison to various existing lists of 'greatest' films, such as personal favourite lists, voting lists, lists of individual experts, and lists deduced from expert polls, the selection of milestone films is more diverse in terms of genres, actors, and main creators. Our results shed light on the potential of a systematic quantitative investigation based on cinematic influences in identifying the most inspiring creations in world cinema. In a broader perspective, we introduce a novel research question to large-scale citation analysis, one of the most intriguing topics that have been at the forefront of scientific enquiries for the past fifty years and have led to the development of various network analytic methods. In doing so, we transfer widely studied approaches from citation analysis to the the newly emerging field of quantification efforts in the arts. The specific contribution of this paper consists in modelling the multidimensional cinematic references as a growing multiplex network and in developing a methodology for the identification of central films in this network.

  7. Measuring long-term impact based on network centrality: unraveling cinematic citations.

    Science.gov (United States)

    Spitz, Andreas; Horvát, Emőke-Ágnes

    2014-01-01

    Traditional measures of success for film, such as box-office revenue and critical acclaim, lack the ability to quantify long-lasting impact and depend on factors that are largely external to the craft itself. With the growing number of films that are being created and large-scale data becoming available through crowd-sourced online platforms, an endogenous measure of success that is not reliant on manual appraisal is of increasing importance. In this article we propose such a ranking method based on a combination of centrality indices. We apply the method to a network that contains several types of citations between more than 40,000 international feature films. From this network we derive a list of milestone films, which can be considered to constitute the foundations of cinema. In a comparison to various existing lists of 'greatest' films, such as personal favourite lists, voting lists, lists of individual experts, and lists deduced from expert polls, the selection of milestone films is more diverse in terms of genres, actors, and main creators. Our results shed light on the potential of a systematic quantitative investigation based on cinematic influences in identifying the most inspiring creations in world cinema. In a broader perspective, we introduce a novel research question to large-scale citation analysis, one of the most intriguing topics that have been at the forefront of scientific enquiries for the past fifty years and have led to the development of various network analytic methods. In doing so, we transfer widely studied approaches from citation analysis to the the newly emerging field of quantification efforts in the arts. The specific contribution of this paper consists in modelling the multidimensional cinematic references as a growing multiplex network and in developing a methodology for the identification of central films in this network. PMID:25295877

  8. Results-Based Financing in Mozambique’s Central Medical Store: A Review After 1 Year

    Science.gov (United States)

    Spisak, Cary; Morgan, Lindsay; Eichler, Rena; Rosen, James; Serumaga, Brian; Wang, Angela

    2016-01-01

    ABSTRACT Background: Public health commodity supply chains are typically weak in low-income countries, partly because they have many disparate yet interdependent functions and components. Approaches to strengthening supply chains in such settings have often fallen short—they address technical weaknesses, but not the incentives that motivate staff to perform better. Methods: We reviewed the first year of a results-based financing (RBF) program in Mozambique, which began in January 2013. The program aimed to improve the performance of the central medical store—Central de Medicamentos e Artigos Medicos (CMAM)—by realigning incentives. We completed in-depth interviews and focus group discussions with 33 key informants, including representatives from CMAM and donor agencies, and collected quantitative data on performance measures and use of funds. Implementation: The RBF agreement linked CMAM performance payments to quarterly results on 5 performance indicators related to supply planning, distribution planning, and warehouse management. RBF is predicated on the theory that a combination of carrot and stick—i.e., shared financial incentives, plus increased accountability for results—will spur changes in behavior. Important design elements: (1) indicators were measured against quarterly targets, and payments were made only for indicators that met those targets; (2) targets were set based on documented performance, at levels that could be reasonably attained, yet pushed for improvement; (3) payment was shared with and dependent on all staff, encouraging teamwork and collaboration; (4) results were validated by verifiable data sources; and (5) CMAM had discretion over how to use the funds. Findings: We found that CMAM’s performance continually improved over baseline and that CMAM achieved many of its performance targets, for example, timely submission of quarterly supply and distribution planning reports. Warehouse indicators, such as inventory management and

  9. Genetic Diversity of Porang Populations (Amorphophallus Muelleri Blume) In Central Java and West Java Based on LEAFY Second Intron Marker

    OpenAIRE

    Isna Arofatun Nikmah; Rodiyati Azrianingsih; Didik Wahyudi

    2016-01-01

    Porang (Amorphophallus muelleri Blume) is dispersed and grew well in Java island. This research aimed to determine the genetic diversity of porang populations in Central Java and West Java based on LEAFY second intron (nuclear genome encoding flower development). DNA samples of porang were from previous study, which were obtained from Central Java (Pamedaran, Grobogan, Wonogiri, Karangtengah) and West Java (Cisompet) as in-group. Amorphophallus variabilis from Pamedaran Brebes, Amorphophallus...

  10. Maxillary sinusitis as a complication of infected dens invaginatus in maxillary lateral incisor: A case report

    Directory of Open Access Journals (Sweden)

    Paras Mull Gehlot

    2015-01-01

    Full Text Available Introduction: Maxillary sinusitis can have various origins, including odontogenic origin. Case Report: We describe a case of maxillary sinusitis in a 25-year-old female patient who experienced pain and swelling in the right maxillary region as a complication of infected maxillary lateral incisor. Clinical and radiographic examinations revealed dens invaginatus (DI; Oehler′s type III associated with apical pathosis in the maxillary right lateral incisor, with a large periapical lesion involving the adjacent four teeth. Nonsurgical root canal treatment using calcium hydroxide medicament was carried out for all five teeth, which resulted in gradual diminution of sinusitis, and the patient remained asymptomatic. Discussion: This paper emphasizes the following: (i the challenges posed by DI for root canal treatment because of its anatomical complexity; (ii a nonsurgical approach in the management of a large periapical lesion, using calcium hydroxide medicament; and (iii the interdisciplinary management of conditions of common clinical concern for medical and dental practitioners, for successful outcome.

  11. Theoretical Study of the Effect of Enamel Parameters on Laser-Induced Surface Acoustic Waves in Human Incisor

    Science.gov (United States)

    Yuan, Ling; Sun, Kaihua; Shen, Zhonghua; Ni, Xiaowu; Lu, Jian

    2015-06-01

    The laser ultrasound technique has great potential for clinical diagnosis of teeth because of its many advantages. To study laser surface acoustic wave (LSAW) propagation in human teeth, two theoretical methods, the finite element method (FEM) and Laguerre polynomial extension method (LPEM), are presented. The full field temperature values and SAW displacements in an incisor can be obtained by the FEM. The SAW phase velocity in a healthy incisor and dental caries is obtained by the LPEM. The methods and results of this work can provide a theoretical basis for nondestructive evaluation of human teeth with LSAWs.

  12. Retreatment of a Maxillary Lateral Incisor With Two Separate Root Canals Confirmed With Cone Beam Computed Tomography

    Science.gov (United States)

    Aydemir, Seda; Helvacioglu-Yigit, Dilek; Sinanoglu, Alper; Ozel, Emre

    2015-01-01

    The purpose of this report is to present a rare case of a maxillary lateral incisor exhibiting two separate root canals confirmed by cone-beam computed tomography (CBCT). A 65-year-old female patient with an esthetic complaint regarding her maxillary left lateral incisor was referred to our clinic. During a radiographical examination, an endodontically treated root canal and an extra root canal with an apical lesion were observed. The retreatment was performed. CBCT findings confirmed the root canal mophology of the maxillary left lateral with two distinct canals. We conclude that the CBCT imaging is an adjunctive tool for better assessment of complex root canal systems. PMID:26015823

  13. Studying Geology of Central Texas through Web-Based Virtual Field Trips

    Science.gov (United States)

    Chan, C.; Khan, S. D.; Wellner, J. S.

    2007-12-01

    Each year over 2500 students, mainly non-science majors, take introductory geology classes at the University of Houston. Optional field trips to Central Texas for these classes provide a unique learning opportunity for students to experience geologic concepts in a real world context. The field trips visit Enchanted Rock, Inks Lake, Bee Cave Road, Lion Mountain, and Slaughter Gap. Unfortunately, only around 10% of our students participate in these field trips. We are developing a web-based virtual field trip for Central Texas to provide an additional effective learning experience for students in these classes. The module for Enchanted Rock is complete and consists of linked geological maps, satellite imagery, digital elevation models, 3-D photography, digital video, and 3-D virtual reality visualizations. The ten virtual stops focus on different geologic process and are accompanied by questions and answers. To test the efficacy of the virtual field trip, we developed a quiz to measure student learning and a survey to evaluate the website. The quiz consists of 10 questions paralleling each stop and information on student attendance on the Central Texas field trip and/or the virtual field trip. From the survey, the average time spent on the website was 26 minutes, and overall the ratings of the virtual field trip were positive. Most noticeably students responded that the information on the website was relevant to their class and that the pictures, figures, and animations were essential to the website. Although high correlation coefficients between responses were expected for some questions (i.e., 0.89 for "The content or text of the website was clear" and "The information on the website was easy to read"), some correlations were less expected: 0.77 for "The number of test questions was appropriate" and "The information on the website was easy to read," and 0.70 for "The test questions reinforced the material presented on the website" and "The information on the

  14. New insight into genes in association with asthma: literature-based mining and network centrality analysis

    Institute of Scientific and Technical Information of China (English)

    LIANG Rui; WANG Lei; WANG Gang

    2013-01-01

    Background Asthma is a heterogeneous disease for which a strong genetic basis has been firmly established.Until now no studies have been undertaken to systemically explore the network of asthma-related genes using an internally developed literature-based discovery approach.This study was to explore asthma-related genes by using literaturebased mining and network centrality analysis.Methods Literature involving asthma-related genes were searched in PubMed from 2001 to 2011.Integration of natural language processing with network centrality analysis was used to identify asthma susceptibility genes and their interaction network.Asthma susceptibility genes were classified into three functional groups by gene ontology (GO) analysis and the key genes were confirmed by establishing asthma-related networks and pathways.Results Three hundred and twenty-six genes related with asthma such as IGHE (IgE),interleukin (IL)-4,5,6,10,13,17A,and tumor necrosis factor (TNF)-alpha were identified.GO analysis indicated some biological processes (developmental processes,signal transduction,death,etc.),cellular components (non-structural extracellular,plasma membrane and extracellular matrix),and molecular functions (signal transduction activity) that were involved in asthma.Furthermore,22 asthma-related pathways such as the Toll-like receptor signaling pathway,hematopoietic cell lineage,JAK-STAT signaling pathway,chemokine signaling pathway,and cytokine-cytokine receptor interaction,and 17 hub genes,such as JAK3,CCR1-3,CCR5-7,CCR8,were found.Conclusions Our study provides a remarkably detailed and comprehensive picture of asthma susceptibility genes and their interacting network.Further identification of these genes and molecular pathways may play a prominent role in establishing rational therapeutic approaches for asthma.

  15. Population-based study of central post-stroke pain in Rimini district, Italy

    Directory of Open Access Journals (Sweden)

    Raffaeli W

    2013-09-01

    Full Text Available William Raffaeli,1 Cristina E Minella,2 Francesco Magnani,3 Donatella Sarti3 1ISAL Foundation, Institute for Research on Pain, Torre Pedrera, Rimini, Italy 2Pain Therapy Unit, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy 3Department of Pain Therapy and Palliative Care, Infermi Hospital, Rimini, Italy Abstract: Central post-stroke pain (CPSP is still an underestimated complication of stroke, resulting in impaired quality of life and, in addition to the functional and cognitive consequences of stroke, the presence of CPSP may be associated with mood disorders, such as depression, anxiety, and sleep disturbances. This type of pain may also impair activities of daily living and further worsen quality of life, negatively influencing the rehabilitation process. The prevalence of CSPS in the literature is highly variable (1%–12% according to different studies, and this variability could be influenced by selection criteria and the different ethnic populations being investigated. With this scenario in mind, we performed a population-based study to assess the prevalence of CPSP and its main features in a homogeneous health district (Rimini, Italy, including five hospitals for a total population of 329,970 inhabitants. From 2008 to 2010, we selected 1,494 post-stroke patients and were able to interview 660 patients, 66 (11% of whom reported pain with related tactile and thermal hyperesthesia, accompanied by needle puncture, tingling, swelling, and pressure sensations. Patients reported motor impairment and disability, which influenced their working ability, rehabilitation, and social life. Despite this severe pain state, there was a high percentage of patients who did not receive adequate treatment for pain. Keywords: stroke, central post-stroke pain, disability

  16. Parameters inversion of high central core rockfill dams based on a novel genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    ZHOU Wei; LI ShaoLin; MA Gang; CHANG XiaoLin; MA Xing; ZHANG Chao

    2016-01-01

    Parameters identification of rockfill materials is a crucial issue for high rockfill dams.Because of the scale effect,random sampling and sample disturbance,it is difficult to obtain the actual mechanical properties of rockfill from laboratory tests.Parameters inversion based on in situ monitoring data has been proven to be an efficient method for identifying the exact parameters of the rockfill.In this paper,we propose a modified genetic algorithm to solve the high-dimension multimodal and nonlinear optimal parameters inversion problem.A novel crossover operator based on the sum of differences in gene fragments (SoDX) is proposed,inspired by the cloning of superior genes in genetic engineering.The crossover points are selected according to the difference in the gene fragments,defining the adaptive length.The crossover operator increases the speed and accuracy of algorithm convergence by reducing the inbreeding and enhancing the global search capability of the genetic algorithm.This algorithm is compared with two existing crossover operators.The modified genetic algorithm is then used in combination with radial basis function neural networks (RBFNN) to perform the parameters back analysis of a high central earth core rockfill dam.The settlements simulated using the identified parameters show good agreement with the monitoring data,illustrating that the back analysis is reasonable and accurate.The proposed genetic algorithm has considerable superiority for nonlinear multimodal parameter identification problems.

  17. The PCR-Based Diagnosis of Central Nervous System Tuberculosis: Up to Date

    Directory of Open Access Journals (Sweden)

    Teruyuki Takahashi

    2012-01-01

    Full Text Available Central nervous system (CNS tuberculosis, particularly tuberculous meningitis (TBM, is the severest form of Mycobacterium tuberculosis (M.Tb infection, causing death or severe neurological defects in more than half of those affected, in spite of recent advancements in available anti-tuberculosis treatment. The definitive diagnosis of CNS tuberculosis depends upon the detection of M.Tb bacilli in the cerebrospinal fluid (CSF. At present, the diagnosis of CNS tuberculosis remains a complex issue because the most widely used conventional “gold standard” based on bacteriological detection methods, such as direct smear and culture identification, cannot rapidly detect M.Tb in CSF specimens with sufficient sensitivity in the acute phase of TBM. Recently, instead of the conventional “gold standard”, the various molecular-based methods including nucleic acid amplification (NAA assay technique, particularly polymerase chain reaction (PCR assay, has emerged as a promising new method for the diagnosis of CNS tuberculosis because of its rapidity, sensitivity and specificity. In addition, the innovation of nested PCR assay technique is worthy of note given its contribution to improve the diagnosis of CNS tuberculosis. In this review, an overview of recent progress of the NAA methods, mainly highlighting the PCR assay technique, was presented.

  18. CFD Based Study of Heterogeneous Microclimate in a Typical Chinese Greenhouse in Central China

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-wei; LUO Jin-yao; LI Xiao-ping

    2013-01-01

    Indoor microclimate is important for crop production and quality in greenhouse cultivation. This paper focuses on microclimate study based on a computational fluid dynamics (CFD) model of a typical plastic greenhouse (with a sector shape vertical cross-section) popularly used in central China. A radiation model is added into the CFD model so as to simulate coupling of convective transfers and radiative exchanges at the cover and the roof, instead of using the usual coupling approach based on energy balance. In addition, a fractal permeability model is innovatively adopted in the modeling of the crop canopy. Compared the numerical results with measured experimental data, the model simulation is proved with success. This model then is used to explore the microclimate variable distributions in the greenhouse. It shows that the airflow pattern, temperature and humidity profiles are different from those in a sawtooth Mediterranean-type greenhouse. The study suggests that this deliberately developed CFD model can be served as a useful tool in macroclimate research and greenhouse design investigating.

  19. Status of Thyroid Disorders in Central Nepal: A Tertiary Care Hospital Based Study

    Directory of Open Access Journals (Sweden)

    RV Mahato

    2015-03-01

    Full Text Available Background: Nepal is a Himalayan, landlocked country surrounded by India and China. It is endemic for iodine deficiency disease. Thyroiddysfunction is major health problem among the Nepalese people. Its prevalence increases with age. Screening of thyroid disease is advised inhigh risk population. Objectives: To find out the prevalence of thyroid dysfunction among subjects who attended Biochemistry Departmentof Tribhuwan University Teaching Hospital, Kathmandu, Nepal. Material and Methods: This is a hospital based retrospective studyconducted in the Department of Biochemistry Tribhuwan University Teaching Hospital, Institute of Medicine. This study was designed toinvestigate status of thyroid dysfunction in central Nepal. A total of 5230 cases from all over Nepal were studied in a single year. Blood sampleswere collected, serum separated and thyroid hormones (fT3, fT4 and TSH were assayed by Vitros ECIQ analyser Ortho Clinical DiagonosticsUSA. Result and discussion: Among 5230 subjects prevalence of thyroid dysfunction was 29.0% with subclinical hypothyroidism17%,hypothyroidism 8%, hyperthyroidism 3%, subclinical hyperthyroidism1% and euthyroidism 71%.Higher prevalence was seen in the age group31-45. Conclusion: This study revealed that subclinical and overt hypothyroidism is preponderant followed by sub clinical hyperthyroidism.Females are more vulnerable to the thyroid dysfunction. Since it is a hospital based study, the prevalence of thyroid dysfunction may not beapplicable. So an extensive demographic survey should be done to provide accurate data of thyroid dysfunction in the general population

  20. Central retinal vein occlusion: A review of current Evidence-based treatment options

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    Amy Patel

    2016-01-01

    Full Text Available A central retinal vein occlusion (CRVO can induce an ischemic and hypoxic state with resulting sequelae of macular edema and neovascularization. Many treatment options have been studied. Our review aims to investigate the safety and efficacy of the multiple treatment options of CRVO. A PubMed and Cochrane literature search was performed. Well-controlled randomized clinical trials that demonstrated strong level 1 evidence-based on the rating scale developed by the British Centre for Evidence-Based Medicine were included. Seven clinical trials met inclusion criteria to be included in this review. These included studies that investigated the safety and efficacy of retinal photocoagulation (1 study, intravitreal steroid treatment (2 studies, and antivascular endothelial growth factor treatment (4 studies for the treatment of CRVO. In addition, studies evaluating surgical treatment options for CRVO were also included. Many treatment modalities have been demonstrated to be safe and efficacious in the treatment of CRVO. These treatment options offer therapeutic benefits for patients and clinically superior visual acuity and perhaps the quality of life after suffering from a CRVO.

  1. Characteristics and Composition of Atmospheric Aerosols in Phimai, Central Thailand During BASE-ASIA

    Science.gov (United States)

    Li, Can; Tsay, Si-Chee; Hsu, N. Christina; Kim, Jin Young; Howell, Steven G.; Huebert, Barry J.; Ji, Qiang; Jeong, Myeong-Jae; Wang, Sheng-Hsiang; Hansell, Richard A.; Bell, Shaun W.

    2012-01-01

    Popular summary: Atmospheric aerosols play an important role in the Earth's climate system, and can also have adverse effects on air quality and human health. The environmental impacts of aerosols, on the other hand, are highly regional, since their temporal/spatial distribution is inhomogeneous and highly depends on the regional emission sources. To better understand the effects of aerosols, intensive field experiments are necessary to characterize the chemical and physical properties on a region-by-region basis. From late February to early May in 2006, NASA/GSFC's SMARTLabs facility was deployed at a rural site in central Thailand, Southeast Asia, to conduct a field experiment dubbed BASE-ASIA (Biomass-burning Aerosols in South East-Asia: Smoke Impact Assessment). The group was joined by scientists from the University of Hawaii and other regional institutes. Comprehensive measurements were made during the experiment, including aerosol chemical composition, optical and microphysical properties, as well as surface energetics and local . meteorology. This study analyzes part of the data from the BASE-ASIA experiment. It was found that, even for the relatively remote rural site, the aerosol loading was still substantial. Besides agricultural burning in the area, industrial pollution near the Bangkok metropolitan area, about 200 km southeast of the site, and even long-range transport from China, also contribute to the area's aerosol loading. The results indicate that aerosol pollution has developed into a regional problem for northern Indochina, and may become more severe as the region's population and economy continue to grow. Abstract: Comprehensive measurements of atmospheric aerosols were made in Phimai, central Thailand (15.l83 N, 102.565 E, elevation: 206 m) during the BASE-ASIA field experiment from late February to early May in 2006. The observed aerosol loading was sizable for this rural site (mean aerosol scattering: 108 +/- 64 Mm(exp -1); absorption: 15

  2. Status and future transition of rapid urbanizing landscape in central Western Ghats - CA based approach

    Science.gov (United States)

    Bharath, S..; Rajan, K. S.; Ramachandra, T. V.

    2014-11-01

    The land use changes in forested landscape are highly complex and dynamic, affected by the natural, socio-economic, cultural, political and other factors. The remote sensing (RS) and geographical information system (GIS) techniques coupled with multi-criteria evaluation functions such as Markov-cellular automata (CA-Markov) model helps in analysing intensity, extent and future forecasting of human activities affecting the terrestrial biosphere. Karwar taluk of Central Western Ghats in Karnataka state, India has seen rapid transitions in its forest cover due to various anthropogenic activities, primarily driven by major industrial activities. A study based on Landsat and IRS derived data along with CA-Markov method has helped in characterizing the patterns and trends of land use changes over a period of 2004-2013, expected transitions was predicted for a set of scenarios through 2013-2022. The analysis reveals the loss of pristine forest cover from 75.51% to 67.36% (1973 to 2013) and increase in agriculture land as well as built-up area of 8.65% (2013), causing impact on local flora and fauna. The other factors driving these changes are the aggregated level of demand for land, local and regional effects of land use activities such as deforestation, improper practices in expansion of agriculture and infrastructure development, deteriorating natural resources availability. The spatio temporal models helped in visualizing on-going changes apart from prediction of likely changes. The CA-Markov based analysis provides us insights into the localized changes impacting these regions and can be useful in developing appropriate mitigation management approaches based on the modelled future impacts. This necessitates immediate measures for minimizing the future impacts.

  3. Centrality measures in networks based on nodes attributes, long-range interactions and group influence

    CERN Document Server

    Aleskerov, F; Shvydun, S

    2016-01-01

    We propose a new method for assessing agents influence in network structures, which takes into consideration nodes attributes, individual and group influences of nodes, and the intensity of interactions. This approach helps us to identify both explicit and hidden central elements which cannot be detected by classical centrality measures or other indices.

  4. Hyperlipidemia induced by high-fat diet enhances dentin formation and delays dentin mineralization in mouse incisor.

    Science.gov (United States)

    Ye, Xin; Zhang, Jin; Yang, Pishan

    2016-10-01

    Dyslipidemia has become a serious health problem in children and adolescents worldwide for its high prevalence. Since hard tissues of permanent teeth form mainly during this period and lipids are actively involved in tooth development, the effects of hyperlipidemia on dental tissue formation and mineralization need to be illustrated. In this study, hyperlipidemia model was established in mice fed with high-fat diet (HFD). Micro-CT and histomorphological analyses were performed on the mandibular bones to assess the morphological changes of the mandibular incisor and first molar. After 4 weeks of HFD feeding, mice had significantly elevated serum lipid levels compared with mice fed with control diet. After 8 weeks, the mandibular incisor presented significantly increased dentin thickness and decreased diameter of pulp cavity in HFD-fed mice compared with control diet-fed mice, while its gross morphology and enamel thickness were not altered. In the mandibular first molar, dentin thickness of root did not show difference between the two groups. Histological section showed that mandibular incisor of HFD-fed mice manifested a wider predentin region and a lower mineral apposition rate compared with that of the control mice. In conclusion, hyperlipidemia induced by HFD feeding enhances dentin formation and delays dentin mineralization in the developing mouse incisor.

  5. Does experience influence the forces exerted on maxillary incisors during laryngoscopy? A manikin study using the Macintosh laryngoscope

    NARCIS (Netherlands)

    M.J.L. Bucx (Martin); R.T.M. van Geel (R. T M); J.T. Wegener (J.); C. Robers (C.); Th. Stijnen (Theo)

    1995-01-01

    textabstractThe influence of the level of experience of the laryngoscopist on the duration of laryngoscopy, the forces exerted on the tongue and on the maxillary incisors during laryngoscopy, were investigated. Five groups (anaesthetists, residents in anaesthesia, nurse anaesthetists, surgeons and m

  6. Prediction of width of un-erupted incisors, canines and premolars in a Ugandan population: A cross sectional study

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    Buwembo William

    2012-07-01

    Full Text Available Abstract Background Accurate prediction of the space forms an important part of an orthodontic assessment in the mixed dentition. However the most commonly used methods of space analysis are based on data developed on Caucasian populations. In order to provide more accurate local data we set out to develop a formula for predicting the widths of un-erupted canines and premolars for a Ugandan population and to compare the predicted widths of the teeth from this formula with those obtained from Moyers’ tables, and Tanaka and Johnston’s equations. Methods Dental casts were prepared using mandibular and maxillary arch impressions of 220 children (85 boys/135 girls aged 12–17 years recruited from schools in Kampala, Uganda. The mesio-distal width of the mandibular incisors, mandibular and maxillary canines and premolars were measured with a pair of digital calipers. Based on regression analysis, predictive equations were derived and the findings were compared with those presented in Moyers’ probability tables, and Tanaka and Johnston’s equations. Results There were no statistically significant differences between the tooth widths predicted by our equations and those from Moyers’ probability tables at the 65th and 75th percentile probabilities for the girls and at 75th level in boys in the mandibular arch. While in the maxillary arch no statistically significant differences at the 75th and 95th levels were noted in girls. There were statistically significant differences between predicted tooth sizes using equations from the present study and those predicted from the Tanaka and Johnston regression equations. Conclusions In this Ugandan population, Moyers’ probability tables could be used to predict tooth widths at specific percentile probabilities, but generally, Tanaka and Johnston technique tends to overestimate the tooth widths.

  7. 3D VISION-BASED DIETARY INSPECTION FOR THE CENTRAL KITCHEN AUTOMATION

    Directory of Open Access Journals (Sweden)

    Yue-Min Jiang

    2014-12-01

    Full Text Available This paper proposes an intelligent and automatic dietary inspection system which can be applied to the dietary inspection for the application of central kitchen automation. The diet specifically designed for the patients are required with providing personalized diet such as low sodium intake or some necessary food. Hence, the proposed system can benefit the inspection process that is often performed manually. In the proposed system, firstly, the meal box can be detected and located automatically with the vision-based method and then all the food ingredients can be identified by using the color and LBP-HF texture features. Secondly, the quantity for each of food ingredient is estimated by using the image depth information. The experimental results show that the dietary inspection accuracy can approach 80%, dietary inspection efficiency can reach1200ms, and the food quantity accuracy is about 90%. The proposed system is expected to increase the capacity of meal supply over 50% and be helpful to the dietician in the hospital for saving the time in the diet inspection process.

  8. Incidence and mechanism of central pontine myelinolysis based on analysis of MRI images and risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Masato [Akita Univ. (Japan). School of Medicine

    2000-02-01

    In this study, the incidence of central pontine myelinolysis (CPM)-like lesions on MRI images was studied in 1917 subjects, 1,500 of which were psychiatric patients and 417 were patients attending a brain health examination. The CPM-like lesions were first classified into four groups based on the characteristics of their MRI images: group 1 showed symmetrical lesions on both T1 low and T2 high images and were considered to be typical CPM; group 2 showed symmetrical high intensity lesions only on T2 images; group 3 had asymmetrical lesions only on T2 images; and group 4 had asymmetrical lesions on both T1 low and T2 high images. Furthermore, the relationships of each group with particular risk factors, such as alcoholism, hypertension, hyperlipidemia were statistically analysed. The cause of CPM-like features in the MRI images were discussed. Among our subjects, the incidence of CPM-like lesions was 3.8%, and that of group 1 was 1.2%. Significant correlations between group 1 and alcoholism, and group 3 and 4 with brain ischemic lesions were observed. A previous hypothesis that group 2 may be a premature state of CPM is not supported by our results. (author)

  9. CO2 Total Column Variability From Ground-Based FTIR Measurements Over Central Mexico

    Science.gov (United States)

    Baylon, J. L.; Stremme, W.; Plaza, E.; Bezanilla, A.; Grutter, M.; Hase, F.; Blumenstock, T.

    2014-12-01

    There are now several space missions dedicated to measure greenhouse gases in order to improve the understanding of the carbon cycle. Ground based measurement sites are of great value in the validation process, however there are only a few stations in tropical latitudes. We present measurements of solar-absorption infrared spectra recorded on two locations over Central Mexico: the High-Altitude Station Altzomoni (19.12 N, 98.65 W), located in the Izta-Popo National Park outside of Mexico City; and the UNAM's Atmospheric Observatory (19.32 N, 99.17 W) in Mexico City. These measurements were performed using a high resolution Fourier transform infrared spectrometer FTIR (Bruker, HR 120/5) at Altzomoni and a moderate resolution FTIR (Bruker, Vertex 80) within the city. In this work, we present the first results for total vertical columns of CO2 derived from near-infrared spectra recorded at both locations using the retrieval code PROFFIT. We present the seasonal cycle and variability from the measurements, as well as the full diagnostics of the retrieval in order assess its quality and discuss the differences of both instruments and locations (altitudes, urban vs remote). This work aims to contribute to generate high quality datasets for satellite validation.

  10. The Contribution of a Central Pattern Generator in a Reflex-Based Neuromuscular Model

    Directory of Open Access Journals (Sweden)

    Florin eDzeladini

    2014-06-01

    Full Text Available Although the concept of central pattern generators (CPGs controlling locomotion in vertebrates is widely accepted, the presence of specialized CPGs in human locomotion is still a matter of debate. An interesting numerical model developed in the 90s' demonstrated the important role CPGs could play in human locomotion, both in terms of stability against perturbations, and in terms of speed control. Recently, a reflex-based neuro-musculo-skeletal model has been proposed, showing a level of stability to perturbations similar to the previous model, without any CPG components. Although exhibiting striking similarities with human gaits, the lack of CPG makes the control of speed/step length in the model difficult. In this paper, we hypothesize that a CPG component will offer a meaningful way of controlling the locomotion speed. After introducing the CPG component in the reflex model, and taking advantage of the resulting properties, a simple model for gait modulation is presented.The results highlight the advantages that a feedforward component can have in terms of gait modulation.

  11. Incidence and mechanism of central pontine myelinolysis based on analysis of MRI images and risk factors

    International Nuclear Information System (INIS)

    In this study, the incidence of central pontine myelinolysis (CPM)-like lesions on MRI images was studied in 1917 subjects, 1,500 of which were psychiatric patients and 417 were patients attending a brain health examination. The CPM-like lesions were first classified into four groups based on the characteristics of their MRI images: group 1 showed symmetrical lesions on both T1 low and T2 high images and were considered to be typical CPM; group 2 showed symmetrical high intensity lesions only on T2 images; group 3 had asymmetrical lesions only on T2 images; and group 4 had asymmetrical lesions on both T1 low and T2 high images. Furthermore, the relationships of each group with particular risk factors, such as alcoholism, hypertension, hyperlipidemia were statistically analysed. The cause of CPM-like features in the MRI images were discussed. Among our subjects, the incidence of CPM-like lesions was 3.8%, and that of group 1 was 1.2%. Significant correlations between group 1 and alcoholism, and group 3 and 4 with brain ischemic lesions were observed. A previous hypothesis that group 2 may be a premature state of CPM is not supported by our results. (author)

  12. Base of Principal Aquifer for the Elkhorn-Loup Model Area, North-Central Nebraska

    Science.gov (United States)

    McGuire, V.L.; Peterson, Sean M.

    2008-01-01

    In Nebraska, the water managers in the Natural Resources Districts and the Nebraska Department of Natural Resources are concerned with the effect of ground-water withdrawal on the availability of surface water and the long-term effects of ground-water withdrawal on ground- and surface-water resources. In north-central Nebraska, in the Elkhorn and Loup River Basins, ground water is used for irrigation, domestic supply, and public supply; surface water is used in this area for irrigation, recreation, and hydropower production. In recognition of these sometimes competing ground- and surface-water uses in the Elkhorn and Loup River Basins, the U.S. Geological Survey, the Lewis and Clark Natural Resources District, the Lower Elkhorn Natural Resources District, the Lower Loup Natural Resources District, the Lower Niobrara Natural Resources District, the Lower Platte North Natural Resources District, the Middle Niobrara Natural Resources District, the Upper Elkhorn Natural Resources District, and the Upper Loup Natural Resources District agreed to cooperatively study water resources in the Elkhorn and Loup River Basins. The goals of the overall study were to construct and calibrate a regional ground-water flow model of the area and to use that flow model as a tool to assess current and future effects of ground-water irrigation on stream base flow and to help develop long-term water-resource management strategies for this area, hereafter referred to as the Elkhorn-Loup model area. The Elkhorn-Loup model area covers approximately 30,800 square miles, and extends from the Niobrara River in the north to the Platte River in the south. The western boundary of the Elkhorn-Loup model area coincides with the western boundary of the Middle Niobrara, Twin Platte, and Upper Loup Natural Resources Districts; the eastern boundary coincides with the approximate location of the western extent of glacial till in eastern Nebraska. The principal aquifer in most of the Elkhorn-Loup model

  13. Combined treatment of a lateral incisor with palato-radicular groove: 1 year follow-up

    Directory of Open Access Journals (Sweden)

    Gülen Kamak

    2014-01-01

    Full Text Available Periodontic - endodontic lesion with a palato-radicular groove as a contributing factor for periodontitis is the most important diagnostic and therapeutic challenges faced by periodontists and the maxillary lateral incisors are the most frequently affected teeth. These developmental grooves promotes the accumulation of plaque and calculus, which destroys the sulcular epithelium and later deeper parts of the periodontium, finally resulting in the formation of a severe localized periodontal lesion since proper cleaning of that site is difficult, if not impossible, for the patient. There are different types of treatment such as scaling and root planning, odontoplasty, amalgam restoration, and extraction of the tooth to treat palatogingival groove and associated periodontal bone defects. In this case, a successful management of an endodontic-periodontal combined lesion by combined treatment and guided tissue regeneration was presented.

  14. Agenesis of maxillary lateral incisor in an Angle Class II, Division 1 malocclusion patient

    Directory of Open Access Journals (Sweden)

    Guilherme Thiesen

    2015-10-01

    Full Text Available The present case report describes the orthodontic treatment of a patient with agenesis of maxillary left lateral incisor and Angle Class II, Division 1 malocclusion. The patient also presented with maxillary midline deviation and inclination of the occlusal plane in the anterior region. Treatment objectives were: correction of sagittal relationship between the maxilla and the mandible; correction of midline deviation, so as to cause maxillary and mandibular midlines to coincide; correction of overbite and leveling of the occlusal plane, so as to create ideal conditions for esthetic rehabilitation of anterior teeth. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO as a requirement for the title of certified by the BBO.

  15. Palatogingival Groove: Recognizing and Managing the Hidden Tract in a Maxillary Incisor: A Case Report.

    Science.gov (United States)

    Sharma, Sarang; Deepak, Passi; Vivek, Sharma; Ranjan Dutta, Shubha

    2015-06-01

    Palatogingival grooves are developmental malformations quite notorious for precipitating endodontic - periodontal lesions. Owing to their inconspicuous occurrence, funnel-shaped morphology and variable extent on tooth root, they promote adherence of plaque and bacteria to levels significant for the development of pathology. Several treatment approaches have been recognized in literature for the management of this anomaly. Here in this report, a 25-year-old patient reported with the complaint of pain and swelling in maxillary right lateral incisor. Clinical examination confirmed an endodontic - periodontal lesion in relation to palatogingival groove. Endodontic treatment was instituted, followed by odontoplasty of the groove and restoration with newer calcium silicate cement, Biodentine. Combined endodontic - periodontal approach was successful in resolving the pathology with complete healing seen both clinically and radiographically. Timely diagnosis, prevention and management are highly recommended to prevent tooth loss due to complications arising secondary to their presence. PMID:26124612

  16. Implant-Prosthetic Rehabilitation in Bilateral Agenesis of Maxillary Lateral Incisors with a Mini Split Crest

    Science.gov (United States)

    Figliuzzi, M. M.; Giudice, A.; Pileggi, S.; Pacifico, D.; Marrelli, M.; Tatullo, M.; Fortunato, L.

    2016-01-01

    The reported clinical case describes the surgical procedure of ridge augmentation by using a “split crest” technique with a partial thickness flap and a subsequent implant-prosthetic rehabilitation aimed at treating a bilateral agenesis of the upper lateral incisors. In such cases with vestibule-palatal and mesial-distal scarce bone thicknesses associated with the need of a proper functional and aesthetic rehabilitation, the split crest technique is particularly suitable. In the case we reported, because of the poor bone thicknesses, we performed a minimally invasive split crest which allowed a correct insertion of the fixtures. This technique allowed us to achieve an optimal functional and aesthetic rehabilitation; moreover, we obtained a good emergency profile, ensuring the vitality of the close teeth and ensuring a good primary stability and the following osseointegration of dental implants. PMID:27190658

  17. CONCOMITANT DENS EVAGINATUS & DENS INVAGINATUS IN A MAXILLARY LATERAL INCISOR: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Kamal Kiswani

    2013-07-01

    Full Text Available Dens evaginatus also referred to as a talon's cusp, is a developmental anomalycharacterized by formation of a well - delineated additional cusp that extends from thecementoenamel junction to the incisal edge. Dens invaginatus is a developmentalanomaly caused by invagination of the surface of the tooth crown before calcificationhas occurred. Dens evaginatus and dens invaginatus are usually present in isolationand many cases have been reported. But, their concomitance is highly rare and unusualand requires documentation. A case report of a 9 year old child with a combination ofthe talon cusp and dens invagination in the right maxillary lateral incisor is presentedhere. Such a tooth due to its unusual morphology is susceptible to food lodgmentleading to carious invasion. Hence early diagnosis and prophylactic therapy isimportant.

  18. Implant-Prosthetic Rehabilitation in Bilateral Agenesis of Maxillary Lateral Incisors with a Mini Split Crest

    Directory of Open Access Journals (Sweden)

    M. M. Figliuzzi

    2016-01-01

    Full Text Available The reported clinical case describes the surgical procedure of ridge augmentation by using a “split crest” technique with a partial thickness flap and a subsequent implant-prosthetic rehabilitation aimed at treating a bilateral agenesis of the upper lateral incisors. In such cases with vestibule-palatal and mesial-distal scarce bone thicknesses associated with the need of a proper functional and aesthetic rehabilitation, the split crest technique is particularly suitable. In the case we reported, because of the poor bone thicknesses, we performed a minimally invasive split crest which allowed a correct insertion of the fixtures. This technique allowed us to achieve an optimal functional and aesthetic rehabilitation; moreover, we obtained a good emergency profile, ensuring the vitality of the close teeth and ensuring a good primary stability and the following osseointegration of dental implants.

  19. Evaluation of buccal enamel of deciduous incisors stored in three different solutions with DIAGNOdent laser fluorescence

    Science.gov (United States)

    De Martin Teles, Flavia; Pettorossi Imaparatto, Jose C.; Zanin, Fatima A. A.; Brugnera, Aldo, Jr.

    2003-06-01

    This study evaluated the influence of different storage solutions on teeth from a tooth bank, using DIAGNOdent laser fluorescence at 3 time periods. The storage solutions used in the study were: refrigerated water, saline, and 10% formol. Eighteen visually intact deciduous incisors were divided into three groups of six samples each. The teeth were previously cleaned, dehydrated and measured using DIAGNOdent at the most prominent buccal region of each tooth. Three subsequent measurements were taken at 1, 7 and 15 days. All measurements were taken by the same examiner and averages were recorded for each time period. Results showed that the three solutions had similar responses to laser. ANOVA was applied to verify the correlation between measurements, time periods, and storage solutions. Statistically significant differences were found only between the time periods. In this in vitro study, all three storage solutions influenced the DIAGNOdent measurement results as time elapsed until the 24 h period.

  20. [Prevention of the eruption of an upper later incisor by a compound odontoma. Case report].

    Science.gov (United States)

    Vlcek, Daniel; Reichart, Peter A; Bosshardt, Dieter D; Sleiter, Roberto; Bornstein, Michael M

    2012-01-01

    Odontomas are the most common odontogenic tumours. They are considered as hamartomas - a local tissue malformation without autonomous growth potential - and are non-neoplastic. Clinically and histopathologically, compound and complex odontomas can be differentiated. Compound odontomas consist of a varying number of tooth-like structures and histology show dental tissues in an orderly pattern. Most often compound odontomas are diagnosed in young patients in the anterior maxilla. Patients are rarely complaining of symptoms and they are usually diagnosed during routine radiographic examinations or due to late eruption of permanent or persistence of deciduous teeth. The following case report presents a disturbed eruption of a lateral right incisor of the maxilla in a 8-year old female patient. Clinical, radiological and histopathological characteristics of this lesion will be discussed as well as therapy and follow-up.

  1. Nonsurgical endodontic treatment of a maxillary lateral incisor with dens invaginatus type II: A case report

    Directory of Open Access Journals (Sweden)

    Elham Shadmehr

    2015-01-01

    Full Text Available Dens invaginatus is a rare developmental anomaly of teeth with complex root canal system morphology. The present case describes a peg shape maxillary lateral incisor with dens invaginatus (Oehlers type II, necrotic pulp, and an associated large periradicular lesion. Nonsurgical endodontic treatment was performed with the aim of removing the blind sac with diamond bur under the use of operating surgical microscope. The root canal system was obturated with thermoplastic technique. Final restoration was done using composite. The 20-months clinical and radiological follow up revealed an asymptomatic tooth with healing of the periapical pathology; however, for complete healed periradicular lesion more follow up is needed. This case illustrated that a dens invaginatus malformed teeth with a large periradicular lesion can be managed successfully with nonsurgical root canal therapy (NSRCT.

  2. Palatogingival Groove: Recognizing and Managing the Hidden Tract in a Maxillary Incisor: A Case Report

    Science.gov (United States)

    Sharma, Sarang; Deepak, Passi; Vivek, Sharma; Ranjan Dutta, Shubha

    2015-01-01

    Palatogingival grooves are developmental malformations quite notorious for precipitating endodontic - periodontal lesions. Owing to their inconspicuous occurrence, funnel-shaped morphology and variable extent on tooth root, they promote adherence of plaque and bacteria to levels significant for the development of pathology. Several treatment approaches have been recognized in literature for the management of this anomaly. Here in this report, a 25-year-old patient reported with the complaint of pain and swelling in maxillary right lateral incisor. Clinical examination confirmed an endodontic - periodontal lesion in relation to palatogingival groove. Endodontic treatment was instituted, followed by odontoplasty of the groove and restoration with newer calcium silicate cement, Biodentine. Combined endodontic - periodontal approach was successful in resolving the pathology with complete healing seen both clinically and radiographically. Timely diagnosis, prevention and management are highly recommended to prevent tooth loss due to complications arising secondary to their presence. PMID:26124612

  3. Direct pulp capping in an immature incisor using a new bioactive material

    Directory of Open Access Journals (Sweden)

    Sham S Bhat

    2014-01-01

    Full Text Available Preservation of the pulp in a traumatized immature fractured incisor tooth is of prime importance in order to achieve apexogenesis, a natural apical closure. The main factor influencing this is pulpal protection by a bioactive material proving optimum marginal seal in preventing any microleakage. This case report presents an 8-year-old female diagnosed with Ellis Class 3 fracture of immature tooth 11 involving the mesial pulp horn. Under rubber dam isolation, a partial pulpotomy was performed and the pulp was sealed using a new bioactive material BIODENTINE to stimulate apexogenesis, dentine replacement and pulp protection. The fractured segment was reattached for optimum esthetics, which was a concern for the patient. The patient was followed-up for 1, 3, 6 and 12 months, which revealed continued apical closure and maintenance of pulp vitality. The patient remained asymptomatic. This case report provides evidence for the potential use of Biodentine as an effective pulp capping material in the future.

  4. Evaluation of the lower incisor inclination during alignment and leveling using superelastic NiTi archwires: a laboratory study

    Directory of Open Access Journals (Sweden)

    Carolina Baratieri

    2012-06-01

    Full Text Available OBJECTIVE: The aim of this laboratory study is to evaluate the influence of the shape and the length limitation of superelastic nickel-titanium (NiTi archwires on lower incisors inclination during alignment and leveling. METHODS: Metal teeth mounted on a typodont articulator device were used to simulate a malocclusion of the mandibular arch (-3.5 mm model discrepancy. Three different shapes (Standard, Accuform and Ideal of superelastic NiTi archwires (Sentalloy, GAC, USA were tested. Specimens were divided in two groups: Group I, with no limitation of the archwire length; and Group II, with distal limitation. Each group had thirty specimens divided into three subgroups differentiated by the archwire shape. All groups used round wires with diameters of 0.014-in, 0.016-in, 0.018-in and 0.020-in. The recording of all intervals was accomplished using standardized digital photographs with orthogonal norm in relation to median sagittal plane. The buccolingual inclination of the incisor was registered using photographs and software CorelDraw. RESULTS: The results were obtained using ANOVA and Tukey's test at a significant level of 5%. The inclination of the lower incisor increased in both groups and subgroups. The shape of the archwire had statistically significant influence only in Group I - Standard (11.76º, Ideal (5.88º and Accuform (1.93º. Analyzing the influence of the length limitation, despite the mean incisor tipping in Group II (3.91º had been smaller than Group I (6.52º, no statistically significant difference was found, except for Standard, 3.89º with limitation and 11.76º without limitation. The greatest incisor tipping occurred with the 0.014-in archwires.

  5. Clinic treatment experience on crown fracture of young permanent incisors%年轻恒前牙冠折后的临床治疗体会

    Institute of Scientific and Technical Information of China (English)

    陈敏

    2013-01-01

    Objective To summarize young permanent incisors with crown fracture in clinical methods,to explore the most beneficial development of young permanent teeth a good way.Methods 30 young crown fracture of permanent incisors trauma cases is based on the pulp exposure,pulp without lesions,X ray shows the root development was specific conditions such as different disposal methods,and followed up after treatment for analysis.Results The review 1 week after treatment,direct pulp capping group 2 patients,indirect pulp capping,there were 2 cases of pulpotomy group,1 patient had pain.After 6 months later,indirect pulp capping success in 9 cases,1 case of failure;direct pulp capping success in 4 cases,2 cases failed;pulpotomy success in 5 cases,1 case of failure;apical surgery group induced a successful 8 cases,failure in 1 case.Conclusion The traumatic crown fracture of young permanent teeth should be handled as soon as possible.Not exposed pulp of crown fracture of young permanent incisor using the indirect pulp capping;on the exposed pulp of the young crown fracture of permanent incisors of time under treatment,pulp status,and root development was to take direct pulp capping,pulpotomy,Apexification the different treatment methods,the periodic review after treatment is not missing,until observed for root development and timely completion of root canal treatment.%目的:通过总结年轻恒前牙冠折的临床治疗方法,探讨最有益于年轻恒前牙良好发育的方法.方法:对30颗年轻恒前牙外伤冠折病例根据牙髓是否暴露、牙髓有无病变、X线片显示的根尖发育情况等具体情况采取不同处置方法,治疗后进行随访观察并作分析研究.结果:治疗后1周复查,直接盖髓术组有2例、间接盖髓术组有2例、活髓切断术组有1例出现疼痛.术后6个月复查,间接盖髓术成功9例,失败1例;直接盖髓术成功4例,失败2例;活髓切断术成功5例,失败1例;根尖诱导术组成功8

  6. Indicator minerals as guides to base metal sulphide mineralisation in Betul Belt, central India

    Indian Academy of Sciences (India)

    Biswajit Ghosh; M N Praveen

    2008-08-01

    Zn-bearing minerals that act as indicator minerals for base metal sulphide mineralization from the Proterozoic Betul Belt,central India with special emphasis on their genetic significance have been discussed.Sulphide mineralisation is hosted by the felsic volcanic rocks and has similarities with volcanic-hosted massive sulphide deposits in other parts of the world.Synvolcanic hydrothermal alteration is crudely zoned with an inner high Mg-Ca core and an outer wider envelop of Al-Fe rich mineral assemblage.Most of the prospects have strata bound,moderately to steeply dipping, multiple,sub-parallel sheet like ore bodies composed of disseminated and semi-massive to massive ores.Zn-bearing spinel,staurolite,biotite and ilmenite typically occur within the foot-wall altera- tion zones in close proximity to the sulphide mineralization.Zincian spinel is ubiquitous irrespective of the nature of alteration zone.Zincian staurolite is nearly absent in Mg-Ca alteration zones but commonly present in Al-Fe alteration zone along with zincian ilmenite.Zn-bearing biotite in intimate association with zincian spinel is generally found in Mg-Ca alteration zone and in the transition to Al-Fe alteration zone.Most of these indicator minerals can be considered as products of desulphidation of sphalerite during metamorphism.Mechanisms other than desulphidation like formation of gahnite by overstepping of the zinc saturation limit of biotite during retrogression to chlorite and formation of zincian staurolite at the expense of gahnite is also recorded.Field presence of these minerals has immense significance in exploration in Betul Belt as they occur in close spatial relationship with the sulphide rich zones and therefore act as direct vectors to ore.

  7. Implementation of Central Dogma Based Cryptographic Algorithm in Data Warehouse Architecture for Performance Enhancement

    Directory of Open Access Journals (Sweden)

    Rajdeep Chowdhury

    2015-11-01

    Full Text Available Data warehouse is a set of integrated databases deliberated to expand decision-making and problem solving, espousing exceedingly condensed data. Data warehouse happens to be progressively more accepted theme for contemporary researchers with respect to contemporary inclination towards industry and executive purview. The crucial tip of the proposed work is integrated on delivering an enhanced and an exclusive innovative model based on the intention of enhancing security measures, which at times have been found wanting and also ensuring improved accessibility using Hashing modus operandi. An unsullied algorithm was engendered using the concept of protein synthesis, prevalently studied in Genetics, that is, in the field of Biotechnology, wherein three steps are observed, namely; DNA Replication, Translation and Transcription. In the proposed algorithm, the two latter steps, that is, Translation and Transcription have been taken into account and the concept have been used for competent encryption and proficient decryption of data. Central Dogma Model is the name of the explicit model that accounts for and elucidates the course of action for Protein Synthesis using the Codons which compose the RNA and the DNA and are implicated in numerous bio–chemical processes in living organisms. It could be observed that subsequently a dual stratum of encryption and decryption mechanism has been employed for optimal security. The formulation of the immaculate Hashing modus operandi ensure that there would be considerable diminution of access time, keeping in mind the apt retrieval of all indispensable data from the data vaults. The pertinent appliance of the proposed model with enhanced security might be in its significant service in a variety of organizations where accrual of protected data is of extreme magnitude. The variety of organizations might include educational organizations, corporate houses, medical establishments, private establishments and so on

  8. Remote Sensing Based Biophysical Characterization of Tropical Deciduous Forest in Central India

    Science.gov (United States)

    Singh, R. P.; Goroshi, S.; Sharma, N. K.; Bairagi, G. D.; Sharma, R.; Jalil, P.; Jain, A.; Sonakia, A.; Parihar, J. S.

    2011-09-01

    The paper reports the measurements of biophysical parameters using field and satellite data over a tropical deciduous forest Kanha National Park (KNP), central India. Field measurement (GBH, LAI, litter, soil moisture) was carried out over ten quadrates of 0.1ha in KNP for characterization of biophysical parameters with specified measurement protocol and sampling. Satellite based remote sensing analysis (LAI, Phenology, and NPP) was carried out using multi date observations of IRS-LISS-III, IMS-1MX, SPOT-VEGETATION and EOS-MODIS instruments. Rank correlation analysis using field data collected in the selected quadrates at KNP showed Sal (Shorea robusta) is dominant forest species followed by Lendia, Jamun (Syzygium cumini), Saja, Harra and Dhawda etc. Field measurement of Sal showed GBH range from 20 cm to 170 cm. Different forest classes such as Sal; Sal mixed with Jamun, Bamboo (Dendrocalamus strictus) etc, including grasslands/scrubland were classified with overall accuracy of 85.56 percent using March, May and October multi spectral data. Sal has distinct growth characteristics (low vegetation growth/ leaf fall in March instead of May) as compared to other vegetation species. As per the Leaf Area Index (LAI) measurement using hemispherical photographs, Sal showed the highest LAI (6.95 m2/m2) during September and lowest LAI (2.63 m2/m2) during March. Overall good agreement (r= 0.79) was found between the LAI generated from LISS-III and MODIS data product. It was observed from SPOT-VEGETATION analysis that NPP varied from 8.4 tC/ha/year (dry deciduous forest) to 14.25 tC/ha/year (Moist deciduous forest) in KNP.

  9. Lineage-based analysis of the development of the central complex of the Drosophila brain.

    Science.gov (United States)

    Pereanu, Wayne; Younossi-Hartenstein, Amelia; Lovick, Jennifer; Spindler, Shana; Hartenstein, Volker

    2011-03-01

    Most neurons of the central complex belong to 10 secondary (larvally produced) lineages. In the late larva, undifferentiated axon tracts of these lineages form a primordium in which all of the compartments of the central complex can be recognized as discrete entities. Four posterior lineages (DPMm1, DPMpm1, DPMpm2, and CM4) generate the classes of small-field neurons that interconnect the protocerebral bridge, fan-shaped body, noduli, and ellipsoid body. Three lineages located in the anterior brain, DALv2, BAmv1, and DALcl2, form the large-field neurons of the ellipsoid body and fan-shaped body, respectively. These lineages provide an input channel from the optic tubercle and connect the central complex with adjacent anterior brain compartments. Three lineages in the posterior cortex, CM3, CP2, and DPMpl2, connect the posterior brain neuropil with specific layers of the fan-shaped body. Even though all of the compartments of the central complex are prefigured in the late larval brain by the axon tracts of the above-mentioned lineages, the neuropil differentiates during the first 2 days of the pupal period when terminal branches and synapses of secondary neurons are formed. During this phase the initially straight horizontal layers of the central complex bend in the frontal plane, which produces the characteristic shape of the fan-shaped and ellipsoid body. Our analysis provides a comprehensive picture of the lineages that form the central complex, and will facilitate future studies that address the structure or function of the central complex at the single cell level. PMID:21246549

  10. Deep sounding TEM investigation method based on a modified fixed central-loop system

    Science.gov (United States)

    Xue, Guo-qiang; Bai, Chao-ying; Yan, Shu; Greenhalgh, Stewart; Li, Mei-fang; Zhou, Nan-nan

    2012-01-01

    The central-loop TEM technology has been widely used in mineral exploration, engineering and environmental investigations and assorted geologic studies. For easy and efficient working conditions, a square (or rectangular) loop is generally employed instead of a circular one. Any position within the inner one ninth of the central part of the loop is often designated as the central survey location (within which the field is assumed to be uniform), and referred to as a modified central-loop configuration. However, the deduced field parameters at such non-central positions when calculated by a central-loop formula result in decreased accuracy and possibly erroneous interpretation. A large-fixed loop offers the advantage of being able to determine the induced potential at any point inside or outside the loop. In this study we provide the formula for the large-fixed loop and receiver positions within the modified central-loop system and solve the problem. Specifically, we compute the electromagnetic response of any field point by using an electric dipole integration method. The full time-domain apparent resistivity values are then extracted by using an iterative method. Both theoretical modeling and real data examples indicate that such a configuration not only improves the accuracy for the TEM survey, but also enlarges the exploration depth, due to a large loop used in the deployment. The method is used for locating the water enriched areas in coal mines in Yangquan region of Shanxi province and in Bin County of Shaanxi province, China. The interpreted results are tested by later drilling, which confirmed our combined method to be a reliable and efficient method for deep sounding.

  11. Memory and Working-with-Memory: A Component Process Model Based on Modules and Central Systems.

    Science.gov (United States)

    Moscovitch, M

    1992-01-01

    Abstract A neuropsychological model of memory is proposed that incorporates Fodor's (1983) idea of modules and central systems. The model has four essential components: (1) a non-frontal neocortical component that consists of perceptual (and perhaps interpretative semantic) modules that mediate performance on item-specific, implicit tests of memory, (2) a modular medial temporal/hippocampal component that mediates encoding, storage, and retrieval on explicit, episodic tests of memory that are associative/cue dependent, (3) a central system, frontal-lobe component that mediates performance on explicit tests that are strategic and on procedural tests that are rule-bound, and (4) a basal ganglia component that mediates performance on sensorimotor, procedural tests of memory. The usefulness of the modular/central system construct is explored and evidence from studies of normal, amnesic, agnosic, and demented people is provided to support the model. PMID:23964882

  12. Comparing the Gibraltar and Calabrian subduction zones (central western Mediterranean) based on seismic tomography

    Science.gov (United States)

    Argnani, Andrea; Battista Cimini, Giovanni; Frugoni, Francesco; Monna, Stephen; Montuori, Caterina

    2016-04-01

    The Central Western Mediterranean (CWM) was shaped by a complex tectonic and geodynamic evolution. Deep seismicity and tomographic studies point to the existence, under the Alboran and Tyrrhenian Seas, of lithospheric slabs extending down to the bottom of the mantle transition zone, at 660 km depth. Two narrow arcs correspond to the two slabs, the Gibraltar and Calabrian Arcs (e.g., Monna et al., 2013; Montuori et al., 2007). Similarities in the tectonic and mantle structure of the two areas have been explained by a common subduction and roll-back mechanism for the opening of the CWM, in which the two arcs are symmetrical end products. In spite of this unifying model, a wide amount of literature from different disciplines shows that many aspects of the two areas are still controversial. We present a new 3-D tomographic model at mantle scale for the Calabrian Arc and compare it with a recently published 3-D tomographic model for the Gibraltar Arc by Monna et al (2013). The two models are based on non-linear inversion of teleseismic phase arrivals, and have scale and parametrization that allow for a direct comparison. Unlike previous studies the tomographic models here presented include Ocean Bottom Seismometer broadband data, which improved the resolution of the mantle structures in the marine areas surrounding the arcs. We focus on key features of the two models that constrain reconstructions of the geodynamic evolution of the CWM (e.g., Monna et al., 2015). At Tortonian time the opening of the Tyrrhenian basin was in its initial stage, and the Calabrian arc formed subsequently; on the contrary, the Gibraltar arc was almost completely defined. We hypothesize that the complexity of the continental margin approaching the subduction zone played a key role during the final stages of the arc formation. References Monna, S., G. B. Cimini, C. Montuori, L. Matias, W. H. Geissler, and P. Favali (2013), New insights from seismic tomography on the complex geodynamic evolution

  13. Geodiversity of the Umbria region (central Italy): a GIS-based quantitative index

    Science.gov (United States)

    Melelli, Laura; Pica, Alessia; Del Monte, Maurizio

    2014-05-01

    The measure of natural range related to geological bedrock, landforms and geomorphological processes is the necessary starting point to geodiversity evaluation. Geodiversity plays a strategic role in landscape management. Whereas geotourism and geosites are identified as a driving power for the scientific and economic promotion of an area, the geodiversity knowledge is required for a complete and accurate research. For example, high values of this abiotic parameter identify and support the foundation of geoparks. According to this perspective, the geodiversity is the unifying factor for these areas of interest. While a subjective and qualitative approach may be adequate for geosites definition, identification and cultural promotion, the geodiversity concept needs a different evaluation method. A quantitative procedure allows achieving an objective and repeatable process exportable in different geographic units. Geographical Information Systems and spatial analysis techniques are the base to quantitative evaluation involving topographic, geological and geomorphological data. Therefore, the assessment of a numerical index derived from the overlay of spatial parameters can be conveniently computed in GIS environment. In this study, a geodiversity index is proposed where geological, geomorphological and landcover factors deriving mainly from maps and field survey; topographic ones are employed from DEM and remote sensed data. Each abiotic parameter is modelled in a grid format; focal functions do provide neighbourhood analysis and computing variety statistics. A particular extent is dedicated to topographic information and terrain roughness, that are strictly related to efficiency of geomorphological processes and generally corresponding to the abiotic components variability. The study area is located in central Italy and is characterized by a well known natural heritage. Thirty-seven geosites are detected in the Umbria region, where seven regional and one natural

  14. Centralized optical-frequency-comb-based RF carrier generator for DWDM fiber-wireless access systems

    DEFF Research Database (Denmark)

    Pang, Xiaodan; Beltran, Marta; Sanchez, Jose;

    2014-01-01

    In this paper, we report on a gigabit capacity fiber-wireless system that enables smooth integration between high-speed wireless networks and dense wavelength-division-multiplexing (DWDM) access networks. By employing a centralized optical frequency comb, both the wireline and the wireless services...

  15. Constructing Market-based Economies in Central Asia: A Natural Experiment?

    Directory of Open Access Journals (Sweden)

    Pomfret, Richard

    2010-12-01

    Full Text Available This paper reviews the experience of the five Central Asian countries in the two decades since independence. In the 1990s the five countries looked like a natural experiment. They had similar initial conditions, but different transition strategies. Today that does not appear to have been a useful research agenda, which raises some broader questions for comparative economic studies.

  16. Sensor-based mapping of soil quality on degraded claypan landscapes of the central United States

    Science.gov (United States)

    Claypan soils (Epiaqualfs) in the central USA have experienced severe erosion as a result of tillage practices of the late 1800s and 1900s. Because of the site-specific nature of erosion processes within claypan fields, research is needed to achieve cost-effective sensing and mapping of soil and lan...

  17. Applicability of regression equation using widths of mandibular permanent first molars and incisors as a predictor of widths of mandibular canines and premolars in contemporary Indian population

    OpenAIRE

    Shalin Shah; Vijay Bhaskar; Karthik Venkataraghvan; Prashant Choudhary; Ganesh Mahadevan; Krishna Trivedi

    2013-01-01

    Background: Predicting the size of unerupted teeth during the mixed dentition period is a critical factor in managing the developing occlusion. Different studies found that the combined width of only the four mandibular permanent incisors is not a good predictor of the sum of unerupted mandibular permanent canines and premolars (SPCP). In 2007, Melgaço et al. developed a new method for SPCP by measuring the sum of the mandibular first permanent molars and four mandibular permanent incisors (S...

  18. An evaluation of factors of permanent central crown fractures in 7-12 years old children

    Directory of Open Access Journals (Sweden)

    Ghandehary- Motlagh M. Assistant Professor

    2003-06-01

    Full Text Available Statement of Problem: Central crown fractures of deciduous and permanent teeth lead to unfavorable"npsychological effects on both children and their parents. Moreover, it can cause malocclusion. So,"nrecognizing tooth fracture reasons plays an important role to prevent its side effects."nAim: The aim of this study was to investigate the reasons' of permanent central crown fractures in (7-12"nyears old children."nMaterials and Methods: Records of 218 children, with at least one central tooth fracture, referred to"npediatric department of faculty of dentistry of Tehran University of Medical Sciences, from 1999 to"n2000, were studied. All the related information about fracture such as: reason, location, time, type of"nocclusion, and type of fracture were recorded."nResults: It was found that falling down (45.4% and having contact with external objects (21.6% were"nthe main reasons for permanent centrals fractures. The mean age of these children was 9.78±1.24 and"n63.3% of them were boys. It should be noted that 41.3% of them had unsupported lip. The highest rate of"nfractures belonged to upper centrals. Based on Ellis classification, most fractures were of degree 3"n(52.7%. There was no significant relationship between overbite and overjet with the degree of fracture"n(P<0.05."nConclusion: Dental skeletal malocclusions such as CI II, Div I, central incisors protrusion and"ndevelopmental defects of tooth structure should be considered as determinant factors in tooth crown"nfractures.

  19. Epidemiology of traumatic injuries to the permanent incisors of 9-12-year-old schoolchildren in Damascus, Syria.

    Science.gov (United States)

    Marcenes, W; al Beiruti, N; Tayfour, D; Issa, S

    1999-06-01

    This cross-sectional survey was carried out to assess epidemiological data concerning dental injuries to the permanent incisors of Syrian children. It included 1087 children aged 9 to 12 years, of both sexes, randomly selected from public and private primary schools in Damascus. The response rate was 100%. The prevalence of traumatic injuries to the permanent incisors rose from 5.2% at the age of 9 years to 11.7% at the age of 12 years (P = 0.007). The difference in prevalence between boys and girls was not statistically significant (P > 0.05). The majority (59.8%) of children who had experienced injuries to the permanent incisors reported that they were not taken to the dentist for evaluation or treatment of the damage. Among those children who had experienced traumatic injuries to the teeth 93.1% presented with untreated damage. Because some injuries were minor, such as small enamel fractures, the proportion of children who needed treatment was 63.2%. There was a tendency for children with an incisal overjet greater than 5 mm to have experienced dental injuries (P = 0.06). Children with inadequate lip coverage were more likely to have experienced dental injuries than those with adequate lip coverage (P = 0.000). The most common reported cause of injuries to the permanent incisors was violence (42.5%), followed by traffic accidents (24.1%), collisions with people or inanimate objects (16.0%) and falls (9.1%). In conclusion, traumatic dental injury may pose a serious dental public health problem. PMID:10530154

  20. The investigation of Optical Coherence Tomography as a clinical tool to determine the extent of Molar Incisor Hypomineralisation (MIH) Lesions

    OpenAIRE

    Al-Azri, K. M. H.

    2015-01-01

    Molar incisor hypomineralisation (MIH) is associated with abnormal mineralisation of enamel during tooth development. It is probably related to systemic upset during this stage of enamel formation. Diagnosing this condition at an early stage is essential in its management, due to complications such as hypersensitivity, post-eruptive breakdown and rapid carious progression in the affected teeth. The current diagnostic measures are clinical visual examination with the aid of indices which are u...

  1. Replacement of missing lateral incisors with lithium disilicate glass-ceramic veneer-fixed dental prostheses: a clinical report

    OpenAIRE

    Bissasu, Sami M; Al-houri, Nabil A

    2014-01-01

    Key Clinical Message This report describes the use of lithium disilicate glass-ceramic veneer-fixed dental prostheses in replacing congenitally missing maxillary lateral incisors. This kind of prosthesis has an advantage over a lingual-retainer resin-bonded fixed dental prosthesis in its capability of changing the color and shape of the abutment teeth. The prostheses provided an acceptable esthetics and comfort for the patient.

  2. Treatment outcome and efficacy of an aligner technique – regarding incisor torque, premolar derotation and molar distalization

    Science.gov (United States)

    2014-01-01

    Background The aim of this study was to investigate the efficacy of orthodontic treatment using the Invisalign® system. Particularly, we analyzed the influence of auxiliaries (Attachment/Power Ridge) as well as the staging (movement per aligner) on treatment efficacy. Methods We reviewed the tooth movements of 30 consecutive patients who required orthodontic treatment with Invisalign®. In all patients, one of the following tooth movements was performed: (1) Incisor Torque >10°, (2) Premolar derotation >10° (3) Molar distalization >1.5 mm. The groups (1)-(3) were subdivided: in the first subgroup (a) the movements were supported with the use of an attachment, while in the subgroup (b) no auxiliaries were used (except incisor torque, in which Power Ridges were used). All tooth movements were performed in a split-mouth design. To analyze the clinical efficacy, pre-treatment and final plaster cast models were laser-scanned and the achieved tooth movement was determined by way of a surface/surface matching algorithm. The results were compared with the amount of tooth movement predicted by ClinCheck®. Results The overall mean efficacy was 59% (SD = 0.2). The mean accuracy for upper incisor torque was 42% (SD = 0.2). Premolar derotation showed the lowest accuracy with approximately 40% (SD = 0.3). Distalization of an upper molar was the most effective movement, with efficacy approximately 87% (SD = 0.2). Conclusion Incisor torque, premolar derotation and molar distalization can be performed using Invisalign® aligners. The staging (movement/aligner) and the total amount of planned movement have an significant impact on treatment efficacy. PMID:24923279

  3. Mandibular lateral incisor with four root canals: A unique case of double tooth diagnosed using multidetector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Sunil Kumar; Acharya, Shashi Rashmi; Ather, Amber; Gupta, Jaya [Manipal College of Dental Sciences, Manipal University, Manipal (India)

    2013-06-15

    Double tooth is a dental anomaly consequent to fusion of two or more teeth or gemination of a single tooth. This report describes a unique case of double tooth in relation to a mandibular lateral incisor exhibiting the presence of four root canals. The role of conventional radiography and advanced three-dimensional imaging techniques in the better assessment of complex root canal systems and their aid in endodontic management has also been highlighted.

  4. A Review of a Successful Unsubsidized Market-Based Rural Solar Development Initiative in Laikipia District, Central Kenya

    OpenAIRE

    O. Wambuguh

    2013-01-01

    The development of renewable energy technologies (RETs) in many areas far from grid-based electricity have primarily involved solar photovoltaics (SPVs) which tap solar radiation to provide heat, light, hot water, electricity, and cooling for homes, businesses, and industry. A study on RETs took place in the Wiyumiririe Location of Laikipia District (north-central Kenya), a rich agricultural region. To explore this solar initiative in such a remote part of the country, a purposive randomized ...

  5. Integration of vision and central pattern generator based locomotion for path planning of a non-holonomic crawling humanoid robot

    OpenAIRE

    Gay, Sébastien; Dégallier Rochat, Sarah; Ijspeert, Auke; Santos-Victor, José

    2010-01-01

    In this paper we present our work on integrating a locomotion controller based on central pattern generator (CPG) and a motion planning algorithm using artificial potential fields for a non-holonomic crawling humanoid robot, the iCub. We also integrated a vision tracker and an inverse kinematics solver to perform reaching tasks. We study the influence of the various parameters of the potential field equations on the performance of the system and prove the efficiency of our framework by testin...

  6. Aetiologies of Central Nervous System infections in adults in Kathmandu, Nepal: A prospective hospital-based study

    OpenAIRE

    Giri, Abhishek; Arjyal, Amit; Koirala, Samir; Karkey, Abhilasha; Dongol, Sabina; Thapa, Sudeep Dhoj; Shilpakar, Olita; Shrestha, Rishav; Van Tan, Le; Thi Thuy Chinh, Bkrong Nguyen; Krishna K. C., Radheshyam; Pathak, Kamal Raj; Shakya, Mila; Farrar, Jeremy; Van Doorn, H. Rogier

    2013-01-01

    We conducted a prospective hospital based study from February 2009-April 2011 to identify the possible pathogens of central nervous system (CNS) infections in adults admitted to a tertiary referral hospital (Patan Hospital) in Kathmandu, Nepal. The pathogens of CNS infections were confirmed in cerebrospinal fluid (CSF) using molecular diagnostics, culture (bacteria) and serology. 87 patients were recruited for the study and the etiological diagnosis was established in 38% (n = 33). The bacter...

  7. Mineral Deposit Data for Epigenetic Base- and Precious-metal and Uranium-thorium Deposits in South-central and Southwestern Montana and Southern and Central Idaho

    Science.gov (United States)

    Klein, T.L.

    2004-01-01

    Metal deposits spatially associated with the Cretaceous Boulder and Idaho batholiths of southwestern Montana and southern and central Idaho have been exploited since the early 1860s. Au was first discovered in placer deposits; exploitation of vein deposits in bedrock soon followed. In 1865, high-grade Ag vein deposits were discovered and remained economically important until the 1890s. Early high-grade deposits of Au, Ag and Pb were found in the weathered portions of the veins systems. As mining progressed to deeper levels, Ag and Pb grades diminished. Exploration for and development of these vein deposits in this area have continued until the present. A majority of these base- and precious-metal vein deposits are classified as polymetallic veins (PMV) and polymetallic carbonate-replacement (PMR) deposits in this compilation. Porphyry Cu and Mo, epithermal (Au, Ag, Hg and Sb), base- and precious-metal and W skarn, W vein, and U and Th vein deposits are also common in this area. The world-class Butte Cu porphyry and the Butte high-sulfidation Cu vein deposits are in this study area. PMV and PMR deposits are the most numerous in the region and constitute about 85% of the deposit records compiled. Several types of syngenetic/diagenetic sulfide mineral deposits in rocks of the Belt Supergroup or their equivalents are common in the region and they have been the source of a substantial metal production over the last century. These syngenetic deposits and their metamorphosed/structurally remobilized equivalents were not included in this database; therefore, deposits in the Idaho portion of the Coeur d'Alene district and the Idaho Cobalt belt, for example, have not been included because many of them are believed to be of this type.

  8. Finite element analysis of maxillary incisor displacement during en-masse retraction according to orthodontic mini-implant position

    Science.gov (United States)

    Song, Jae-Won; Lim, Joong-Ki; Lee, Kee-Joon; Sung, Sang-Jin; Chun, Youn-Sic

    2016-01-01

    Objective Orthodontic mini-implants (OMI) generate various horizontal and vertical force vectors and moments according to their insertion positions. This study aimed to help select ideal biomechanics during maxillary incisor retraction by varying the length in the anterior retraction hook (ARH) and OMI position. Methods Two extraction models were constructed to analyze the three-dimentional finite element: a first premolar extraction model (Model 1, M1) and a residual 1-mm space post-extraction model (Model 2, M2). The OMI position was set at a height of 8 mm from the arch wire between the second maxillary premolar and the first molar (low OMI traction) or at a 12-mm height in the mesial second maxillary premolar (high OMI traction). Retraction force vectors of 200 g from the ARH (-1, +1, +3, and +6 mm) at low or high OMI traction were resolved into X-, Y-, and Z-axis components. Results In M1 (low and high OMI traction) and M2 (low OMI traction), the maxillary incisor tip was extruded, but the apex was intruded, and the occlusal plane was rotated clockwise. Significant intrusion and counter-clockwise rotation in the occlusal plane were observed under high OMI traction and -1 mm ARH in M2. Conclusions This study observed orthodontic tooth movement according to the OMI position and ARH height, and M2 under high OMI traction with short ARH showed retraction with maxillary incisor intrusion. PMID:27478801

  9. In Vitro Evaluation of Access Cavity Location Effect on Fracture Resistance of Maxillary Central Endodontically Treated Teeth

    OpenAIRE

    Shirinzad, M.; Z. Khamverdi; S. Ghorbani

    2014-01-01

    Introduction & Objective: Preparation of access cavity to root canal is a critical phase in endo-dontic treatment. The purpose of this study was to evaluate the effect of access cavity loca-tion (labial or palatal) on fracture resistance of endodontically treated maxillary central teeth. Materials & Methods: In this experimental laboratorial study, 84 intact human maxillary central incisors with similar dimensions were selected. The teeth were divided into 4 test groups as follows: Group 1 : ...

  10. 3D VISION-BASED DIETARY INSPECTION FOR THE CENTRAL KITCHEN AUTOMATION

    OpenAIRE

    Yue-Min Jiang; Ho-Hsin Lee; Cheng-Chang Lien; Chun-Feng Tai; PiChun Chu; Ting-Wei Yang

    2014-01-01

    This paper proposes an intelligent and automatic dietary inspection system which can be applied to the dietary inspection for the application of central kitchen automation. The diet specifically designed for the patients are required with providing personalized diet such as low sodium intake or some necessary food. Hence, the proposed system can benefit the inspection process that is often performed manually. In the proposed system, firstly, the meal box can be detected and loc...

  11. Regulating the grid-based energies in Central and Eastern Europe: models, status, issues

    International Nuclear Information System (INIS)

    As the electricity, gas and heat industries of the economies in transition move towards more market-oriented frameworks, regulators are established to secure fair competition, protection of the customers and a minimum of public service. The paper describes the various models used or contemplated in the autumn of 2000 in central and eastern Europe and identifies fifteen issues, some falling under the competence of governments, others challenging the regulators, again others relating to international co-operation. (author)

  12. An InSAR-based survey of volcanic deformation in the central Andes

    OpenAIRE

    M. E. Pritchard; Simons, M.

    2004-01-01

    We extend an earlier interferometric synthetic aperture radar (InSAR) survey covering about 900 remote volcanos of the central Andes (14°–27°S) between the years 1992 and 2002. Our survey reveals broad (10s of km), roughly axisymmetric deformation at 4 volcanic centers: two stratovolcanoes are inflating (Uturuncu, Bolivia, and Hualca Hualca, Peru); another source of inflation on the border between Chile and Argentina is not obviously associated with a volcanic edifice (here called Lazufre); a...

  13. Identification keys on rattans (Calamus spp.) from Central Sulawesi based on anatomical structure of stems

    OpenAIRE

    ANDI TANRA TELLU

    2005-01-01

    This study was conducted to obtain information the anatomical characteristics of 20 rattan species from Central Sulawesi and to use it for anatomical identification of rattan species. The rattan comprised 16 Calamus species, three Daemonorops species and one Korthalsia species. For anatomical observation 10-15 mm pieces of the mature stem from shares of tip do not have frond were processed with polyethilene glycol 2000, cut at 18-32 µm and stained with a combination of acridin-cryzoidin red a...

  14. Tectonic structure of Central-Western Attica (Greece) based on geophysical invesigations - preliminary results.

    OpenAIRE

    Papadopoulos, T. D.; Goulty, N.; Voulgaris, N. S.; Alexopoulos, J. D.; Fountoulis, I.; Kambouris, P.; Karastathis, V.; Peirce, C.; S. Chailas; Kassaras, J.; Pirli, M.; Goumas, G.; Lagios, E.

    2007-01-01

    In an effort to investigate the deep geological structure in the broader area of central-western Attica, that suffered severe damage during the destructive Athens earthquake of September 7th, 1999, the Department of Geophysics-Geothermics of the Faculty of Geology and Geoenvironment of Athens University, in collaboration with the Geodynamic Institute of National Observatory of Athens and the Department of Geological Sciences of Durham University, carried out a combined geophysical survey. ...

  15. SensorBase.org - A Centralized Repository to Slog Sensor Network Data

    OpenAIRE

    Chang, Kevin; Yau, Nathan; Hansen, Mark; Estrin, D

    2006-01-01

    Various sensor networks use different data storage and management mechanisms. In particular, UCLA’s ESS2 mechanism forwards information from low powered 8-bit Mica2 motes to one or more low powered sinks that then push log files to a secure and centralized repository. While this data storage and management mechanism is straightforward to implement, publishing and sharing various data to various users has been a challenge. Users that need to parse the data often find it time consuming and erro...

  16. Teachers' professional development in a community: A study of the central actors, their networks and web-based learning

    Directory of Open Access Journals (Sweden)

    Jiri Lallimo

    2008-07-01

    Full Text Available The goal of this article was to study teachers' professional development related to web-based learning in the context of the teacher community. The object was to learn in what kind of networks teachers share the knowledge of web-based learning and what are the factors in the community that support or challenge teachers professional development of web-based learning. The findings of the study revealed that there are teachers who are especially active, called the central actors in this study, in the teacher community who collaborate and share knowledge of web-based learning. These central actors share both technical and pedagogical knowledge of web-based learning in networks that include both internal and external relations in the community and involve people, artefacts and a variety of media. Furthermore, the central actors appear to bridge different fields of teaching expertise in their community.According to the central actors' experiences the important factors that support teachers' professional development of web-based learning in the community are; the possibility to learn from colleagues and from everyday working practices, an emotionally safe atmosphere, the leader's personal support and community-level commitment. Also, the flexibility in work planning, challenging pupils, shared lessons with colleagues, training events in an authentic work environment and colleagues' professionalism are considered meaningful for professional development. As challenges, the knowledge sharing of web-based learning in the community needs mutual interests, transactive memory, time and facilities, peer support, a safe atmosphere and meaningful pedagogical practices.On the basis of the findings of the study it is suggested that by intensive collaboration related to web-based learning it may be possible to break the boundaries of individual teachership and create such sociocultural activities which support collaborative professional development in the teacher

  17. Genes expressed in dental enamel development are associated with molar-incisor hypomineralization.

    Science.gov (United States)

    Jeremias, Fabiano; Koruyucu, Mine; Küchler, Erika C; Bayram, Merve; Tuna, Elif B; Deeley, Kathleen; Pierri, Ricardo A; Souza, Juliana F; Fragelli, Camila M B; Paschoal, Marco A B; Gencay, Koray; Seymen, Figen; Caminaga, Raquel M S; dos Santos-Pinto, Lourdes; Vieira, Alexandre R

    2013-10-01

    Genetic disturbances during dental development influence variation of number and shape of the dentition. In this study, we tested if genetic variation in enamel formation genes is associated with molar-incisor hypomineralization (MIH), also taking into consideration caries experience. DNA samples from 163 cases with MIH and 82 unaffected controls from Turkey, and 71 cases with MIH and 89 unaffected controls from Brazil were studied. Eleven markers in five genes [ameloblastin (AMBN), amelogenin (AMELX), enamelin (ENAM), tuftelin (TUFT1), and tuftelin-interacting protein 11 (TFIP11)] were genotyped by the TaqMan method. Chi-square was used to compare allele and genotype frequencies between cases with MIH and controls. In the Brazilian data, distinct caries experience within the MIH group was also tested for association with genetic variation in enamel formation genes. The ENAM rs3796704 marker was associated with MIH in both populations (Brazil: p=0.03; OR=0.28; 95% C.I.=0.06-1.0; Turkey: p=1.22e-012; OR=17.36; 95% C.I.=5.98-56.78). Associations between TFIP11 (p=0.02), ENAM (p=0.00001), and AMELX (p=0.01) could be seen with caries independent of having MIH or genomic DNA copies of Streptococcus mutans detected by real time PCR in the Brazilian sample. Several genes involved in enamel formation appear to contribute to MIH.

  18. Root canal anatomy study of lower incisors by the clearing technique

    Directory of Open Access Journals (Sweden)

    Daniel GALAFASSI

    2007-05-01

    Full Text Available To succeed in the endodontic therapy, it’s a requisite to have fullknowledge of the inner root anatomy, as well as its variations. Thelower incisors are the tinniest teeth of the human arcade having a root strongly flattened to the mesio-distal way. This flattening is sometimes as big to split the root canal in two, one vestibular and another lingual.This study has utilized the clearing technique (method that allows to see through transparency the diverse root anatomy to accomplish its objective of analyzing the incidence of the canals present in the cervical third, middle and apical of the incisors’ roots of human lowers. For that purpose, 150 teeth have been obtained from the Teeth Bank of the Odontology Faculty of the University of Passo Fundo, on which the clearing technique and the injection of Naquin ink in the pulp cavity interior were applied, followed by the conservation in the methyl salicylate, allowing to three-dimensionally observe, through transparency, the internal anatomy of the root canal. The results have been analyzed by descriptive statistics, in which it was observed that 81,63% of the analyzed samples have presented one canal in the cervical third; 53,06% have two canals in the middle third and 71,42% have one canal in the apical third. With this it can be concluded that there is a major incidence of the root canal bifurcation in the middle third of the root in relation to the cervical and apical.

  19. The application of fiber core posts in restoring badly destroyed primary incisors.

    Science.gov (United States)

    Sharaf, Aly A

    2002-01-01

    Early childhood caries (ECC) represents a challenge to pediatric dentists especially, when teeth are badly destroyed. ECC involves the upper anterior teeth early in life and by the time the dentist sees the child, most of the coronal structure is lost. Dentally, this is a very devastating situation for both the dentist and parents, as in many cases, extraction of these teeth is the only option. With the introduction of new adhesive systems and restorative materials, a new approach for treating these teeth is explained and documented by clinical cases, where fiber core posts are introduced into the root canals of primary incisors for a distance of 2 to 3 mm. It is retained in place by flowable composite, then the coronal part is reconstructed by a strip crown to restore the crown form. After a follow up period of one year, only 2 teeth out of 30 had to be extracted. The failure was attributed to failure in pulpal therapy rather than failure in the restorations, which were totally intact. A laboratory testing of the fracture load resistance of the restored teeth proved that this technique significantly improved the fracture load resistance of composite celluloid crowns, making it a valuable procedure to consider when the coronal tooth structure is not enough to support and retain a composite celluloid strip crown. PMID:11990042

  20. The design of future central receiver power plants based on lessons learned from the Solar One Pilot Plant

    Science.gov (United States)

    Kolb, G. J.

    The 10-MW(sub e) Solar One Pilot Plant was the world's largest solar central receiver power plant. During its power production years it delivered over 37,000 MWhrs (net) to the utility grid. In this type of electric power generating plant, large sun-tracking mirrors called heliostats reflect and concentrate sunlight onto a receiver mounted on top of a tower. The receiver transforms the solar energy into thermal energy that heats water, turning it into superheated steam that drives a turbine to generate electricity. The Solar One Pilot Plant successfully demonstrated the feasibility of generating electricity with a solar central receiver power plant. During the initial 2 years the plant was tested and 4 years the plant was operated as a power plant, a great deal of data was collected relating to the efficiency and reliability of the plant's various systems. This paper summarizes these statistics and compares them to goals developed by the U.S. Department of Energy. Based on this comparison, improvements in the design and operation of future central receiver plants are recommended. Research at Sandia National Laboratories and the U.S. utility industry suggests that the next generation of central receiver power plants will use a molten salt heat transfer fluid rather than water/steam. Sandia has recently completed the development of the hardware needed in a molten salt power plant. Use of this new technology is expected to solve many of the performance problems encountered at Solar One. Projections for the energy costs from these future central receiver plants are also presented. For reference, these projections are compared to the current energy costs from the SEGS parabolic trough plants now operating in Southern California.

  1. Performance of grid-tied PV facilities based on real data in Spain: Central inverter versus string system

    International Nuclear Information System (INIS)

    Highlights: • The operation of two grid-tied PV facilities over a two-year period is presented. • The central inverter system is compared to the string inverter system. • A procedure based on a small number of easily obtained parameters is used. • The string inverter outperforms the central inverter. • Conclusions of use to maintenance firms and operational facilities are obtained. - Abstract: Two complete years of operation of two grid-tied PV facilities is presented. Energetic and economic performance of both installations has been compared. Located in the same place, the installation of these facilities followed the same construction criteria – PV panels, panel support system and wiring – and the facilities are exposed to the same atmospheric temperature and solar radiation. They differ with regard to their inverter topology used: one facility uses a central inverter and the other a string inverter configuration. The performance of the facilities has been determined using a procedure based on a small number of easily obtained parameters and the knowledge of the analyzed system and its operation mode. Electrical losses have been calculated for both systems and a complete comparison between them has been carried out. The results have shown better performance for distributed system in economic and energetic terms

  2. The Discriminative validity of "nociceptive," "peripheral neuropathic," and "central sensitization" as mechanisms-based classifications of musculoskeletal pain.

    LENUS (Irish Health Repository)

    Smart, Keith M

    2012-02-01

    OBJECTIVES: Empirical evidence of discriminative validity is required to justify the use of mechanisms-based classifications of musculoskeletal pain in clinical practice. The purpose of this study was to evaluate the discriminative validity of mechanisms-based classifications of pain by identifying discriminatory clusters of clinical criteria predictive of "nociceptive," "peripheral neuropathic," and "central sensitization" pain in patients with low back (+\\/- leg) pain disorders. METHODS: This study was a cross-sectional, between-patients design using the extreme-groups method. Four hundred sixty-four patients with low back (+\\/- leg) pain were assessed using a standardized assessment protocol. After each assessment, patients\\' pain was assigned a mechanisms-based classification. Clinicians then completed a clinical criteria checklist indicating the presence\\/absence of various clinical criteria. RESULTS: Multivariate analyses using binary logistic regression with Bayesian model averaging identified a discriminative cluster of 7, 3, and 4 symptoms and signs predictive of a dominance of "nociceptive," "peripheral neuropathic," and "central sensitization" pain, respectively. Each cluster was found to have high levels of classification accuracy (sensitivity, specificity, positive\\/negative predictive values, positive\\/negative likelihood ratios). DISCUSSION: By identifying a discriminatory cluster of symptoms and signs predictive of "nociceptive," "peripheral neuropathic," and "central" pain, this study provides some preliminary discriminative validity evidence for mechanisms-based classifications of musculoskeletal pain. Classification system validation requires the accumulation of validity evidence before their use in clinical practice can be recommended. Further studies are required to evaluate the construct and criterion validity of mechanisms-based classifications of musculoskeletal pain.

  3. Turbine model for the Laguna Verde nucleo electric central based in the RELAP code

    International Nuclear Information System (INIS)

    The Nuclear Power stations as Laguna Verde occupy at the present time a place every time but important as non pollutant alternative, economic and trusty to generate electricity. It is for it that the Group of Nuclear Engineering of the Engineering Faculty (GrlNFI) of the National Autonomous University of Mexico (UNAM) it develops investigation projects applied to Nuclear Centrals. One of the projects in process is the development of a Classroom simulator, which it can configures to consent to diverse models of nuclear systems with training purposes in normal operation, or, to consent to specialized nuclear codes for the analysis of transitory events and have a severe accident. This work describes the development, implementation and it proves of a simplified model of the Main turbine to be integrated to the group of models of the Classroom simulator. It is part of the current effort of GrlNFI guided to obtain a representation of all the dynamic models necessary to simulate the Plant Balance of the Laguna Verde Central. It is included the development of the unfolding graphic which represent the modeling of the Main turbine, and of the control interface that allows the user to manipulate in simple way, direct and interactive this device during the training or the analysis. With this work it is wanted to contribute to the training of new technicians and to support the operation personnel of the Centrals. Also, the developed infrastructure is guided to contribute in the design and analysis of new Nuclear Power stations with the contribution of new computational tools for the visualization, simulation and process control. (Author)

  4. STRATEGIC PURCHASING IN A PROJECT- BASED COMPANY – TO CENTRALIZE OR DECENTRALIZE

    Directory of Open Access Journals (Sweden)

    Eva Donociková

    2014-03-01

    Full Text Available Organizations all lie on a spectrum, at one end of which are firms with complete centralization of purchasing, and at the other end are firms with complete decentralization. Most firms lie somewhere between the two extremes, and we have already mentioned the most common model that has certain decisions centralized (perhaps strategy design, selection of suppliers, purchasing of major capital equipment, training, co-ordination, communications, etc. and bulk of purchasing devolved to local buyers. There are many variations on the type of activities that are either centralized or decentralized. In the last 12 years purchasing has noticed two radical changes in the majority of facilities. First change was the reverse of supplier – customer relationships where the role of purchasers changed from persuading and begging the suppliers to ever deliver, preferably with minimum delay (for fixed prices, to standard purchase activities where the purchaser can choose from many suppliers and negotiate prices with vendors to achieve the best conditions for his buyer. The second change was the establishing of a modern IT system that made purchasing activities more effective, more automatic and transparent to a considerable extent. It is good to realize whether all changes have led to improvement or whether these changes have caused a stop or a slowdown of the project purchasing – whether it is possible or even necessary to take into account global as well as local suppliers or to combine them. This Case Study demonstrates how a project - managed organization could look like, where it is necessary to take into account customer´s wishes and benefit.

  5. Caribou, individual-based modeling and mega-industry in central West Greenland

    DEFF Research Database (Denmark)

    Raundrup, Katrine; Nymand, Josephine; Nabe-Nielsen, Jacob;

    Spatial distribution of caribou (Rangifer tarandus groenlandicus) in West Greenland is a result of both short and long term changes in the Arctic landscape. To understand present distribution 40 satellite collars were deployed on 40 female caribou in the Akia-Maniitsoq herd, central West Greenland...... distribution and caribou in a realistic but manipulable “virtual world” of an IBM it is possible to examine the plausible effects of different environmental impacts on the population dynamics of caribou in West Greenland. The simulations will include introduction of mega-industry, roads, and transmission lines...

  6. Structures based on semi-degradable biomaterials for neural regeneration in the central nervous system

    OpenAIRE

    Perez Garnes, Manuel

    2015-01-01

    Se pretende obtener un material semibiodegradable basado en ácido hialurónico químicamente enlazado a cadenas de polímeros acrílicos. Los hidrogeles de ácido hialurónico presentan en general buenas características para su utilización en regeneración del sistema nervioso central: es biodegradable, es un componente importante del tejido neural, sus propiedades mecánicas son semejantes a las del tejido cerebral, promueve la formación de nuevos capilares (angiogénesis), y limita la inflamación. C...

  7. Maximum principle and convergence of central schemes based on slope limiters

    KAUST Repository

    Mehmetoglu, Orhan

    2012-01-01

    A maximum principle and convergence of second order central schemes is proven for scalar conservation laws in dimension one. It is well known that to establish a maximum principle a nonlinear piecewise linear reconstruction is needed and a typical choice is the minmod limiter. Unfortunately, this implies that the scheme uses a first order reconstruction at local extrema. The novelty here is that we allow local nonlinear reconstructions which do not reduce to first order at local extrema and still prove maximum principle and convergence. © 2011 American Mathematical Society.

  8. Ocular biometry and central corneal thickness in children: a hospital-based study

    Directory of Open Access Journals (Sweden)

    Adem Gul

    2014-06-01

    Full Text Available Objetivo: Investigar a distribuição do comprimento axial, profundidade da câmara anterior, espessura do cristalino, profundidade da câmara vítrea e espessura corneal central em crianças em diferentes faixas etárias. Métodos: Foram estudados 364 olhos de 182 crianças entre 1 e 12 anos de idade. O comprimento axial, a profundidade da câmara anterior , a espessura do cristalino e a profundidade da câmara vítrea foram medidos por biometria ultrassônica. A espessura corneal central foi medida por paquimetria ultrassônica em todas as crianças. Resultados: A idade média foi de 6,54 ± 3,42 anos. O comprimento axial foi 20,95 mm no grupo de 1-2 anos de idade e 22,95 mm no grupo de 11-12 anos de idade. A espessura corneal central foi 556 µm no grupo de 1-2 anos de idade e 555 µm no grupo de 11-12 anos de idade. A profundidade da câmara anterior média e profundidade da câmara vítrea aumentou com a idade (3,06 mm a 3,44 mm de profundidade da câmara anterior, 13,75 mm a 15,99 mm de profundidade da câmara vítrea e da espessura do cristalino diminuiu com o aumento da idade (3,67 mm a 3,51 mm. Conclusões: Em nosso estudo, os valores do comprimento axial aumentou com a idade e atingiu os níveis adultos aos 9-10 anos de idade. A espessura do cristalino diminuiu gradualmente até os 12 anos de idade. As medições de espessura corneal central não seguiu um algoritmo linear.

  9. Identification keys on rattans (Calamus spp. from Central Sulawesi based on anatomical structure of stems

    Directory of Open Access Journals (Sweden)

    ANDI TANRA TELLU

    2005-04-01

    Full Text Available This study was conducted to obtain information the anatomical characteristics of 20 rattan species from Central Sulawesi and to use it for anatomical identification of rattan species. The rattan comprised 16 Calamus species, three Daemonorops species and one Korthalsia species. For anatomical observation 10-15 mm pieces of the mature stem from shares of tip do not have frond were processed with polyethilene glycol 2000, cut at 18-32 µm and stained with a combination of acridin-cryzoidin red and astrablue. Cleared preparation were used to observe stegmata, and macerated material was used to measure the length of fibers and vessel elements. Anilin sulfate was used to confirm the existence of lignin. Anatomical characteristics used in identification were shape and will thickening of epidermal cells and the position stomata at epidermal; the arrangement of sub epidermal parenchyma; composition of vascular bundles and their distribution; the shape and arrangement of central ground parenchyma and the occurrence of fiber bundles. The research result indicated that the anatomical character can be compiled to a key identify the rattan at genus and species level.

  10. Sensor-Based Programming of Central Pattern Generators in Humanoid Robots

    Directory of Open Access Journals (Sweden)

    Hamed Shahbazi

    2013-04-01

    Full Text Available In the present article, a method for generating curvilinear bipedal walking patterns is proposed which is able to generate rhythmic and periodic trajectories for a Nao soccer player robot. To do so, a programmable central pattern generator was used which was inspired from locomotion structures in vertebrate animals. In this paper, the programmable central pattern generators were extended and new Equations were added to make a curvilinear pattern for walking Nao robots on a specified circular curve. In addition, some specific Equations were added to the model to control the arms and synchronize them with the movement of the feet. The model uses some sensory inputs to obtain some feedback from the movement and adjust it conforming to the potential perturbations. Input sensory values consist of accelerator values and foot pressure sensor values located on the bottom of each foot. Feedback values can adopt walking to some desired specifications and compensate the effects of some types of perturbations. The proposed model has many benefits including smooth walking patterns and modulation during walking. This model can be extended and used in the Nao soccer player both for the standard platform and the 3D soccer simulation leagues of Robocup SPL competitions to train different types of motions.

  11. Identifying the Critical Links in Road Transportation Networks: Centrality-based approach utilizing structural properties

    Energy Technology Data Exchange (ETDEWEB)

    Chinthavali, Supriya [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    Surface transportation road networks share structural properties similar to other complex networks (e.g., social networks, information networks, biological networks, and so on). This research investigates the structural properties of road networks for any possible correlation with the traffic characteristics such as link flows those determined independently. Additionally, we define a criticality index for the links of the road network that identifies the relative importance in the network. We tested our hypotheses with two sample road networks. Results show that, correlation exists between the link flows and centrality measures of a link of the road (dual graph approach is followed) and the criticality index is found to be effective for one test network to identify the vulnerable nodes.

  12. A Novel Particle Swarm Optimization based Algorithm for the Optimal Centralized Wireless Access Network

    Directory of Open Access Journals (Sweden)

    Dac-Nhuong Le

    2013-01-01

    Full Text Available The wireless access networks design problem is formulated as a constrained optimization problem, where the goal is to find a network topology such that an objective function is optimized, subject to a set of constraints. The objective function may be the total cost, or some performance measure like utilization, call blocking or throughput. The constraints may be bounds on link capacities, cost elements, or some network performance measure. However, the optimization problem is too complex. In this paper, we propose a novel Particle Swarm Optimization (PSO algorithm to finding the total cost of connecting the BSs to the MSCs, and connecting the MSCs to the LE called by the optimal centralized wireless access network. Numerical results show that performance of our proposed algorithm is much better than previous studies.

  13. A new map of the vegetation of central European Russia based on high-resolution satellite data.

    Science.gov (United States)

    Ershov, D V; Gavrilyuk, E A; Karpukhina, D A; Kovganko, K A

    2015-01-01

    The scientific basis of and approaches to regional thematic mapping of vegetation based on high-resolution satellite data have been elaborated. A vegetation map of central European Russia has been compiled. The map includes 12 thematic classes, six of which pertain to forest ecosystems. The map has been compared to the data of the GFC project (University of Maryland, United States) and the official data of the Rosstat Federal Service of State Statistics (Russia). The new vegetation map is currently used in the information system of the remote monitoring of forest fires in Russia. PMID:26530069

  14. Aerosol optical depth over central north Asia based on MODIS-Aqua data

    Science.gov (United States)

    Avgousta Foutsi, Athina; Korras Carraca, Marios Bruno; Matsoukas, Christos; Biskos, George

    2016-04-01

    Atmospheric aerosols, both natural and anthropogenic, can affect the regional and global climate through their direct, indirect, and semi-direct effects on the radiative energy budget of the Earth-atmosphere system. To quantify these effects it is important to determine the aerosol load, and an effective way to do that is by measuring the aerosol optical depth (AOD). The central Asia region (mainly the Caspian and Aral sea basins), the arid and semi-arid regions of Western China as well as Siberia are of great interest due to the significant natural sources of mineral aerosols originating from local deserts and biomass burning from wildfires in boreal forests. What is of particular interest in the region is the phenomenal shrinking and desertification of the Aral Sea that drives an intense salt and dust transport from the exposed sea-bed to the surrounding regions with important implications in regional air quality. Anthropogenic particles are also observed due to fossil-fuel combustion occurring mainly at oil refineries in the Caspian Sea basin. Here we investigate the spatial and temporal variability of the AOD at 550 nm over central Asia, Siberia and western China, in the region located between 35° N - 65° N and 45° E - 110° E. For our analysis we use Level-3 daily MODIS - Aqua Dark Target - Deep Blue combined product, from the latest collection (006), available in a 1°×1° resolution (ca. 100 km × 100 km) over the period 2002-2014. Our results indicate a significant spatial variability of the aerosol load over the study region. The highest AODs are observed over the Aral Sea year-round, with extreme values reaching 2.1 during July. In the rest of our study region a clear seasonal cycle with highest AOD values (up to 1.2 over the Taklamakan Desert) during spring and summer is observed. The arid parts of central north Asia are characterized by larger aerosol loads during spring, lower but still high AOD in summer and much lower values in autumn and spring

  15. Nanofibrous scaffolds supporting optimal central nervous system regeneration: an evidence-based review

    Directory of Open Access Journals (Sweden)

    Kamudzandu M

    2015-12-01

    Full Text Available Munyaradzi Kamudzandu, Paul Roach, Rosemary A Fricker, Ying Yang Institute for Science and Technology in Medicine, School of Medicine, Keele University, Stoke-on-Trent, UK Abstract: Restoration of function following damage to the central nervous system (CNS is severely restricted by several factors. These include the hindrance of axonal regeneration imposed by glial scars resulting from inflammatory response to damage, and limited axonal outgrowth toward target tissue. Strategies for promoting CNS functional regeneration include the use of nanotechnology. Due to their structural similarity, synthetic nanofibers could play an important role in regeneration of CNS neural tissue toward restoration of function following injury. Two-dimensional nanofibrous scaffolds have been used to provide contact guidance for developing brain and spinal cord neurites, particularly from neurons cultured in vitro. Three-dimensional nanofibrous scaffolds have been used, both in vitro and in vivo, for creating cell adhesion permissive milieu, in addition to contact guidance or structural bridges for axons, to control reconnection in brain and spinal cord injury models. It is postulated that nanofibrous scaffolds made from biodegradable and biocompatible materials can become powerful structural bridges for both guiding the outgrowth of neurites and rebuilding glial circuitry over the “lesion gaps” resulting from injury in the CNS. Keywords: scaffold, nanofibrous scaffold, CNS, regeneration, alignment

  16. Soil erosion history in central Tanzania based on OSL dating of colluvial and alluvial hillslope deposits

    Science.gov (United States)

    Eriksson, M. G.; Olley, J. M.; Payton, R. W.

    2000-12-01

    The Irangi Hills in Kondoa District, central Tanzania, are severely degraded by sheet, rill and gully erosion. Using recently developed optically stimulated luminescence (OSL) dating techniques, and a detailed study of the hillslope stratigraphy and soils, we have determined the sequence of events that gave rise to this highly degraded landscape. Two major colluvial deposits have been identified on the slopes. The oldest colluvium gave OSL deposition dates of 14,700±1600, 14,200±1500 and 11,400±1300 years ago. These dates coincide with the climatic change from dry to wet conditions, which took place during the Late Pleistocene. It is possible that the erosion and deposition of the old colluvium occurred as a response to this change. This phase of erosion and deposition was followed by a long phase of stability and pedogenetic alteration of the old colluvium. A phase of accelerated soil erosion began not later than 900 years ago, as indicated by a dated alluvial fan, the presence of which indicates that some deeper gullies already existed on upper pediment slopes at that time. The second, more recent colluvial deposit gave OSL dates of 460±40, 590±70 and 660±50 years. A major period of gully formation and incision, with subsequent fan development, occurred sometime between 600 and 300 years ago. The recent phase of erosion (livestock husbandry and iron smelting practices in the Irangi Hills.

  17. Kinematics of the New Madrid seismic zone, central United States, based on stepover models

    Science.gov (United States)

    Pratt, Thomas L.

    2012-01-01

    Seismicity in the New Madrid seismic zone (NMSZ) of the central United States is generally attributed to a stepover structure in which the Reelfoot thrust fault transfers slip between parallel strike-slip faults. However, some arms of the seismic zone do not fit this simple model. Comparison of the NMSZ with an analog sandbox model of a restraining stepover structure explains all of the arms of seismicity as only part of the extensive pattern of faults that characterizes stepover structures. Computer models show that the stepover structure may form because differences in the trends of lower crustal shearing and inherited upper crustal faults make a step between en echelon fault segments the easiest path for slip in the upper crust. The models predict that the modern seismicity occurs only on a subset of the faults in the New Madrid stepover structure, that only the southern part of the stepover structure ruptured in the A.D. 1811–1812 earthquakes, and that the stepover formed because the trends of older faults are not the same as the current direction of shearing.

  18. Structure tensor based automated detection of macular edema and central serous retinopathy using optical coherence tomography images.

    Science.gov (United States)

    Hassan, Bilal; Raja, Gulistan; Hassan, Taimur; Usman Akram, M

    2016-04-01

    Macular edema (ME) and central serous retinopathy (CSR) are two macular diseases that affect the central vision of a person if they are left untreated. Optical coherence tomography (OCT) imaging is the latest eye examination technique that shows a cross-sectional region of the retinal layers and that can be used to detect many retinal disorders in an early stage. Many researchers have done clinical studies on ME and CSR and reported significant findings in macular OCT scans. However, this paper proposes an automated method for the classification of ME and CSR from OCT images using a support vector machine (SVM) classifier. Five distinct features (three based on the thickness profiles of the sub-retinal layers and two based on cyst fluids within the sub-retinal layers) are extracted from 30 labeled images (10 ME, 10 CSR, and 10 healthy), and SVM is trained on these. We applied our proposed algorithm on 90 time-domain OCT (TD-OCT) images (30 ME, 30 CSR, 30 healthy) of 73 patients. Our algorithm correctly classified 88 out of 90 subjects with accuracy, sensitivity, and specificity of 97.77%, 100%, and 93.33%, respectively. PMID:27140751

  19. Spontaneous eruption of an occult incisor fragment from the lip after eight months: report of a case.

    Science.gov (United States)

    Rao, Dinesh; Hegde, Sapna

    2006-01-01

    Large majorities of dental traumas are associated with soft-tissue injury and tooth fragments. They are often found embedded in the oral soft tissues, most commonly the lip. Early detection and complete removal of such fragments is critical in order to prevent infection and scarring. Adequate communication between medical and dental professionals involved is of considerable value in the management of such cases. This report presents a case of spontaneous extrusion of an occult incisor fragment from the lower lip, eight months after trauma. PMID:16683665

  20. Determination of Strontium by ICP-MS and a Study of the Influence on Native Elements in Incisors of Rats

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov

    in rats. The effects were monitored on calcium, magnesium and phosphorous that key elements in the apatite crystal in 160 rats treated with 0, 100, 300 or 1000 mg/kg/day strontium malonate for 6 months by oral gavage. After termination femurs and incisors were excised and after thorough rinsing, digestion...... was conducted under controlled hydrothermal conditions. The elements Ca, Mg, Na, P and Sr were quantified in all samples by ICP-MS, from working curves containing up to 20 calibration points, and the measurements were validated on NIST SRM 1486 and 1640. The ability to incorporate strontium in bone...

  1. Trends in health facility based maternal mortality in Central Region, Kenya: 2008-2012

    Science.gov (United States)

    Muchemi, Onesmus Maina; Gichogo, Agnes Wangechi; Mungai, Jane Githuku; Roka, Zeinab Gura

    2016-01-01

    Introduction WHO classifies Kenya as having a high maternal mortality. Regional data on maternal mortality trends is only available in selected areas. This study reviewed health facility maternal mortality trends, causes and distribution in Central Region of Kenya, 2008-2012. Methods We reviewed health records from July 2008 to June 2012. A maternal death was defined according to ICD-10 criterion. The variables reviewed included socio-demographic, obstetric characteristics, reasons for admission, causes of death and contributing factors. We estimated maternal mortality ratio for each year and overall for the four year period using a standard equation and used frequencies means/median and proportions for other descriptive variables. Results A total 421 deaths occurred among 344,191 live births; 335(80%) deaths were audited. Maternal mortality ratios were: 127/100,000 live births in 2008/09; 124/100,000 live births in 2009/2010; 129/100,000 live births in 2010/2011 and 111/100,000 live births in 2011/2012. Direct causes contributed majority of deaths (77%, n=234) including hemorrhage, infection and pre-eclampsia/eclampsia. Mean age was 30(±6) years; 147(71%) attended less than four antenatal visits and median gestation at birth was 38 weeks (IQR=9). One hundred ninety (59%) died within 24 hours after admission. There were 111(46%) caesarian births, 95(39%) skilled vaginal, 31(13%) unskilled 5(2%) vacuum deliveries and 1(<1%) destructive operation. Conclusion The region recorded an unsteady declining trend. Direct causes contributed to the majority deaths including hemorrhage, infection and pre-eclampsia/eclampsia. We recommend health education on individualized birth plan and mentorship on emergency obstetric care. Further studies are necessary to clarify and expand the findings of this study. PMID:27516824

  2. The central role of chloride in the metabolic acid-base changes in canine parvoviral enteritis.

    Science.gov (United States)

    Burchell, Richard K; Schoeman, Johan P; Leisewitz, Andrew L

    2014-04-01

    The acid-base disturbances in canine parvoviral (CPV) enteritis are not well described. In addition, the mechanisms causing these perturbations have not been fully elucidated. The purpose of the present study was to assess acid-base changes in puppies suffering from CPV enteritis, using a modified strong ion model (SIM). The hypothesis of the study was that severe acid-base disturbances would be present and that the SIM would provide insights into pathological mechanisms, which have not been fully appreciated by the Henderson-Hasselbalch model. The study analysed retrospective data, obtained from 42 puppies with confirmed CPV enteritis and 10 healthy control dogs. The CPV-enteritis group had been allocated a clinical score, to allow classification of the data according to clinical severity. The effects of changes in free water, chloride, l-lactate, albumin and phosphate were calculated, using a modification of the base excess algorithm. When the data were summated for each patient, and correlated to each individual component, the most important contributor to the metabolic acid-base changes, according to the SIM, was chloride (Penteritis are multifactorial and complex, with the SIM providing information in terms of the origin of these changes.

  3. Spatial point analysis based on dengue surveys at household level in central Brazil

    Science.gov (United States)

    Siqueira-Junior, João B; Maciel, Ivan J; Barcellos, Christovam; Souza, Wayner V; Carvalho, Marilia S; Nascimento, Nazareth E; Oliveira, Renato M; Morais-Neto, Otaliba; Martelli, Celina MT

    2008-01-01

    Background Dengue virus (DENV) affects nonimunne human populations in tropical and subtropical regions. In the Americas, dengue has drastically increased in the last two decades and Brazil is considered one of the most affected countries. The high frequency of asymptomatic infection makes difficult to estimate prevalence of infection using registered cases and to locate high risk intra-urban area at population level. The goal of this spatial point analysis was to identify potential high-risk intra-urban areas of dengue, using data collected at household level from surveys. Methods Two household surveys took place in the city of Goiania (~1.1 million population), Central Brazil in the year 2001 and 2002. First survey screened 1,586 asymptomatic individuals older than 5 years of age. Second survey 2,906 asymptomatic volunteers, same age-groups, were selected by multistage sampling (census tracts; blocks; households) using available digital maps. Sera from participants were tested by dengue virus-specific IgM/IgG by EIA. A Generalized Additive Model (GAM) was used to detect the spatial varying risk over the region. Initially without any fixed covariates, to depict the overall risk map, followed by a model including the main covariates and the year, where the resulting maps show the risk associated with living place, controlled for the individual risk factors. This method has the advantage to generate smoothed risk factors maps, adjusted by socio-demographic covariates. Results The prevalence of antibody against dengue infection was 37.3% (95%CI [35.5–39.1]) in the year 2002; 7.8% increase in one-year interval. The spatial variation in risk of dengue infection significantly changed when comparing 2001 with 2002, (ORadjusted = 1.35; p < 0.001), while controlling for potential confounders using GAM model. Also increasing age and low education levels were associated with dengue infection. Conclusion This study showed spatial heterogeneity in the risk areas of dengue

  4. Spatial point analysis based on dengue surveys at household level in central Brazil

    Directory of Open Access Journals (Sweden)

    Oliveira Renato M

    2008-10-01

    Full Text Available Abstract Background Dengue virus (DENV affects nonimunne human populations in tropical and subtropical regions. In the Americas, dengue has drastically increased in the last two decades and Brazil is considered one of the most affected countries. The high frequency of asymptomatic infection makes difficult to estimate prevalence of infection using registered cases and to locate high risk intra-urban area at population level. The goal of this spatial point analysis was to identify potential high-risk intra-urban areas of dengue, using data collected at household level from surveys. Methods Two household surveys took place in the city of Goiania (~1.1 million population, Central Brazil in the year 2001 and 2002. First survey screened 1,586 asymptomatic individuals older than 5 years of age. Second survey 2,906 asymptomatic volunteers, same age-groups, were selected by multistage sampling (census tracts; blocks; households using available digital maps. Sera from participants were tested by dengue virus-specific IgM/IgG by EIA. A Generalized Additive Model (GAM was used to detect the spatial varying risk over the region. Initially without any fixed covariates, to depict the overall risk map, followed by a model including the main covariates and the year, where the resulting maps show the risk associated with living place, controlled for the individual risk factors. This method has the advantage to generate smoothed risk factors maps, adjusted by socio-demographic covariates. Results The prevalence of antibody against dengue infection was 37.3% (95%CI [35.5–39.1] in the year 2002; 7.8% increase in one-year interval. The spatial variation in risk of dengue infection significantly changed when comparing 2001 with 2002, (ORadjusted = 1.35; p Conclusion This study showed spatial heterogeneity in the risk areas of dengue when using a spatial multivariate approach in a short time interval. Data from household surveys pointed out that low prevalence areas

  5. An InSAR-based survey of volcanic deformation in the central Andes

    Science.gov (United States)

    Pritchard, M. E.; Simons, M.

    2004-02-01

    We extend an earlier interferometric synthetic aperture radar (InSAR) survey covering about 900 remote volcanos of the central Andes (14°-27°S) between the years 1992 and 2002. Our survey reveals broad (10s of km), roughly axisymmetric deformation at 4 volcanic centers: two stratovolcanoes are inflating (Uturuncu, Bolivia, and Hualca Hualca, Peru); another source of inflation on the border between Chile and Argentina is not obviously associated with a volcanic edifice (here called Lazufre); and a caldera (Cerro Blanco, also called Robledo) in northwest Argentina is subsiding. We explore the range of source depths and volumes allowed by our observations, using spherical, ellipsoidal and crack-like source geometries. We further examine the effects of local topography upon the deformation field and invert for a spherical point-source in both elastic half-space and layered-space crustal models. We use a global search algorithm, with gradient search methods used to further constrain best-fitting models. Inferred source depths are model-dependent, with differences in the assumed source geometry generating a larger range of accepted depths than variations in elastic structure. Source depths relative to sea level are: 8-18 km at Hualca Hualca; 12-25 km for Uturuncu; 5-13 km for Lazufre, and 5-10 km at Cerro Blanco. Deformation at all four volcanoes seems to be time-dependent, and only Uturuncu and Cerro Blanco were deforming during the entire time period of observation. Inflation at Hualca Hualca stopped in 1997, perhaps related to a large eruption of nearby Sabancaya volcano in May 1997, although there is no obvious relation between the rate of deformation and the eruptions of Sabancaya. We do not observe any deformation associated with eruptions of Lascar, Chile, at 16 other volcanoes that had recent small eruptions or fumarolic activity, or associated with a short-lived thermal anomaly at Chiliques volcano. We posit a hydrothermal system at Cerro Blanco to explain the

  6. Knowledge-Based, Central Nervous System (CNS) Lead Selection and Lead Optimization for CNS Drug Discovery.

    Science.gov (United States)

    Ghose, Arup K; Herbertz, Torsten; Hudkins, Robert L; Dorsey, Bruce D; Mallamo, John P

    2012-01-18

    The central nervous system (CNS) is the major area that is affected by aging. Alzheimer's disease (AD), Parkinson's disease (PD), brain cancer, and stroke are the CNS diseases that will cost trillions of dollars for their treatment. Achievement of appropriate blood-brain barrier (BBB) penetration is often considered a significant hurdle in the CNS drug discovery process. On the other hand, BBB penetration may be a liability for many of the non-CNS drug targets, and a clear understanding of the physicochemical and structural differences between CNS and non-CNS drugs may assist both research areas. Because of the numerous and challenging issues in CNS drug discovery and the low success rates, pharmaceutical companies are beginning to deprioritize their drug discovery efforts in the CNS arena. Prompted by these challenges and to aid in the design of high-quality, efficacious CNS compounds, we analyzed the physicochemical property and the chemical structural profiles of 317 CNS and 626 non-CNS oral drugs. The conclusions derived provide an ideal property profile for lead selection and the property modification strategy during the lead optimization process. A list of substructural units that may be useful for CNS drug design was also provided here. A classification tree was also developed to differentiate between CNS drugs and non-CNS oral drugs. The combined analysis provided the following guidelines for designing high-quality CNS drugs: (i) topological molecular polar surface area of <76 Å(2) (25-60 Å(2)), (ii) at least one (one or two, including one aliphatic amine) nitrogen, (iii) fewer than seven (two to four) linear chains outside of rings, (iv) fewer than three (zero or one) polar hydrogen atoms, (v) volume of 740-970 Å(3), (vi) solvent accessible surface area of 460-580 Å(2), and (vii) positive QikProp parameter CNS. The ranges within parentheses may be used during lead optimization. One violation to this proposed profile may be acceptable. The

  7. Beyond the Central Dogma: Model-Based Learning of How Genes Determine Phenotypes

    Science.gov (United States)

    Reinagel, Adam; Speth, Elena Bray

    2016-01-01

    In an introductory biology course, we implemented a learner-centered, model-based pedagogy that frequently engaged students in building conceptual models to explain how genes determine phenotypes. Model-building tasks were incorporated within case studies and aimed at eliciting students' understanding of 1) the origin of variation in a population…

  8. Limited irrigation of corn-based no-till crop rotations in west central Great Plains.

    Science.gov (United States)

    Identifying the most profitable crop rotation for an area is a continuous research challenge. The objective of this study was to evaluate 2, 3, and 4 yr. limited irrigation corn (Zea mays L.) based crop rotations for grain yield, available soil water, crop water productivity, and profitability in co...

  9. Central Issues in the Use of Computer-Based Materials for High Volume Entrepreneurship Education

    Science.gov (United States)

    Cooper, Billy

    2007-01-01

    This article discusses issues relating to the use of computer-based learning (CBL) materials for entrepreneurship education at university level. It considers CBL as a means of addressing the increased volume and range of provision required in the current context. The issues raised in this article have importance for all forms of computer-based…

  10. Management and hazardous waste characterization in Central for Isotop and Radiation Application based on potential dangers

    International Nuclear Information System (INIS)

    Separating and storing hazardous waste have been done based on the physical, chemical, and based on potential dangers due to safety hazardous waste temporary storage warehouse. From the results of data collection in 2014 found that the most dominant hazardous waste is organic liquid waste which reaches 61 %, followed by inorganic liquid waste 33 % while organic solid waste and inorganic solid waste has a small portion. When viewed from potential danger, flammable liquid waste has the greatest volume percentage it is 47 % and is followed by a corrosive liquid waste 26 %, while the liquid waste that has not been identified is quite large, which is 9 %. From the highest hazard potential data, hazardous waste storage warehouse is required to have good air circulation and waste storage shelf protected from direct solar heat. Cooperation of lab workers and researchers are also indispensable in providing identification of each waste generated to facilitate the subsequent waste management. (author)

  11. Centralized Role-Based Access Control for Federated Multi-Domain Environments

    Institute of Scientific and Technical Information of China (English)

    YU Guangcan; LU Zhengding; LI Ruixuan; MUDAR Sarem

    2006-01-01

    The secure interaction among multiple security domains is a major concern. In this paper, we highlight the issues of secure interoperability among multiple security domains operating under the widely accepted Role Based Access Control (RBAC) model. We propose a model called CRBAC that easily establishes a global policy for roles mapping among multiple security domains. Our model is based on an extension of the RBAC model. Also, multiple security domains were composed to one abstract security domain. Also roles in the multiple domains are translated to permissions of roles in the abstract security domain. These permissions keep theirs hierarchies. The roles in the abstract security domain implement roles mapping among the multiple security domains. Then, authorized users of any security domain can transparently access resources in the multiple domains.

  12. DPSK signals demodulation based on a multimode fiber with a central dip

    OpenAIRE

    CHEN Xiaoyong; Rodriguez Horche, Paloma; Martín Minguez, Alfredo

    2014-01-01

    Differential Phase Shift Keying (DPSK) modulation format has been shown as a robust solution for next-generation optical transmission systems. One key device enabling such systems is a delay interferometer, converting the phase modulation signal into the intensity modulation signal to be detected by the photodiodes. Usually, a standard Mach-Zehnder interferometer (MZI) is used for demodulating a DPSK signal. In this paper, we develop an MZI which is based on all-fiber Multimode Interference (...

  13. Implementation of Central Dogma Based Cryptographic Algorithm in Data Warehouse Architecture for Performance Enhancement

    OpenAIRE

    Rajdeep Chowdhury; Soupayan Datta; Saswata Dasgupta; Mallika De

    2015-01-01

    Data warehouse is a set of integrated databases deliberated to expand decision-making and problem solving, espousing exceedingly condensed data. Data warehouse happens to be progressively more accepted theme for contemporary researchers with respect to contemporary inclination towards industry and executive purview. The crucial tip of the proposed work is integrated on delivering an enhanced and an exclusive innovative model based on the intention of enhancing security measures, which at time...

  14. ICT industry and resources based analysis of maintenance SME in the Central Europe

    Directory of Open Access Journals (Sweden)

    Š. Tesar

    2010-12-01

    Full Text Available Highly competitive situation in Information and Communication technology (ICT maintenance industryrequires a precise analysis of all important factors and carefully defined company strategy which addresses eachof these aspects. This paper presents a resource based analysis of family run SME, operating in IT parts andconsumables market. In order to understand this complex view, it first describes the company background. Itbriefly presents the industry key success factors and company strategy of the SME. The value chain analysishelps to name the main organization’s capabilities and evaluates them in terms of costs and customer willingnessto pay. Resource audit provides an analysis of key company tangible, intangible and human resources. Theoutcome of this audit shows that most of SME resources are of an intangible nature. Contrary to the highermobility of today’s resources, intangible resources of SME such as company reputation, culture and strategicbusiness relations, are mostly immobile and inimitable. Based on the audit all key resources and capabilities areappraised by their strength and importance relative to closest rivals. Results are presented in graph whichrecognizes the key strengths (family run business related and weaknesses (IT and finance. The results of theresourced based analysis lead to recommendations for changes in order to create and retain competitiveadvantage.

  15. Prevalence of Obesity and Overweight in an Indigenous Population in Central Brazil: A Population-Based Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Geraldo F. Oliveira

    2015-10-01

    Full Text Available Objective: To estimate the prevalence of obesity and overweight and associated factors in indigenous people of the Jaguapiru village in Central Brazil. Methods: We conducted a population-based cross-sectional study between January 2009 and July 2011 in the adult native population of the Jaguapiru village, Central Brazil. Sociodemographic and lifestyle data were obtained; anthropometric measures, arterial blood pressure, and blood glucose were measured. The independent variables were tested by Poisson regression, and the interactions between them were analyzed. Results: 1,608 indigenous people (982 females, mean age 37.7 ± 15.1 years were included. The prevalence of obesity was 23.2% (95% CI 20.9-25.1%. Obesity was more prevalent among 40- to 49-year-old and overweight among 50- to 59-year-old persons. Obesity was positively associated with female sex, higher income, and hypertension. Among indigenous people, interactions were found with hypertension and sedentary lifestyle - hypertension in males and sedentary lifestyle in females. Conclusions: The prevalence of obesity and overweight in indigenous people of the Jaguapiru village is high. Males as well as hypertensive and higher family income individuals have higher rates. Sedentary lifestyle and hypertension leverage the rates of obesity. Prevention and adequate public health policies can be critical for the control of excess weight and its comorbidities among Brazilian indigenous people.

  16. Configuring calendar variation based on time series regression method for forecasting of monthly currency inflow and outflow in Central Java

    Science.gov (United States)

    Setiawan, Suhartono, Ahmad, Imam Safawi; Rahmawati, Noorgam Ika

    2015-12-01

    Bank Indonesia (BI) as the central bank of Republic Indonesiahas a single overarching objective to establish and maintain rupiah stability. This objective could be achieved by monitoring traffic of inflow and outflow money currency. Inflow and outflow are related to stock and distribution of money currency around Indonesia territory. It will effect of economic activities. Economic activities of Indonesia,as one of Moslem country, absolutely related to Islamic Calendar (lunar calendar), that different with Gregorian calendar. This research aims to forecast the inflow and outflow money currency of Representative Office (RO) of BI Semarang Central Java region. The results of the analysis shows that the characteristics of inflow and outflow money currency influenced by the effects of the calendar variations, that is the day of Eid al-Fitr (moslem holyday) as well as seasonal patterns. In addition, the period of a certain week during Eid al-Fitr also affect the increase of inflow and outflow money currency. The best model based on the value of the smallestRoot Mean Square Error (RMSE) for inflow data is ARIMA model. While the best model for predicting the outflow data in RO of BI Semarang is ARIMAX model or Time Series Regression, because both of them have the same model. The results forecast in a period of 2015 shows an increase of inflow money currency happened in August, while the increase in outflow money currency happened in July.

  17. Detection of planets in extremely weak central perturbation microlensing events via next-generation ground-based surveys

    CERN Document Server

    Chung, Sun-Ju; Koo, Jae-Rim

    2014-01-01

    Even though the recently discovered high-magnification event MOA-2010-BLG-311 had complete coverage over the peak, confident planet detection did not happen due to extremely weak central perturbations (fractional deviations of $\\lesssim 2\\%$). For confident detection of planets in extremely weak central perturbation (EWCP) events, it is necessary to have both high cadence monitoring and high photometric accuracy better than those of current follow-up observation systems.The next-generation ground-based observation project, KMTNet (Korea Microlensing Telescope Network), satisfies the conditions. We estimate the probability of occurrence of EWCP events with fractional deviations of $\\leq 2\\%$ in high-magnification events and the efficiency of detecting planets in the EWCP events using the KMTNet. From this study, we find that the EWCP events occur with a frequency of $> 50\\%$ in the case of $\\lesssim 100\\ M_{\\rm E}$ planets with separations of $0.2\\ {\\rm AU} \\lesssim d \\lesssim 20\\ {\\rm AU}$. We find that for m...

  18. Aetiologies of central nervous system infection in Viet Nam: a prospective provincial hospital-based descriptive surveillance study.

    Directory of Open Access Journals (Sweden)

    Nghia Ho Dang Trung

    Full Text Available BACKGROUND: Infectious diseases of the central nervous system (CNS remain common and life-threatening, especially in developing countries. Knowledge of the aetiological agents responsible for these infections is essential to guide empiric therapy and develop a rational public health policy. To date most data has come from patients admitted to tertiary referral hospitals in Asia and there is limited aetiological data at the provincial hospital level where most patients are seen. METHODS: We conducted a prospective Provincial Hospital-based descriptive surveillance study in adults and children at thirteen hospitals in central and southern Viet Nam between August 2007-April 2010. The pathogens of CNS infection were confirmed in CSF and blood samples by using classical microbiology, molecular diagnostics and serology. RESULTS: We recruited 1241 patients with clinically suspected infection of the CNS. An aetiological agent was identified in 640/1241 (52% of the patients. The most common pathogens were Streptococcus suis serotype 2 in patients older than 14 years of age (147/617, 24% and Japanese encephalitis virus in patients less than 14 years old (142/624, 23%. Mycobacterium tuberculosis was confirmed in 34/617 (6% adult patients and 11/624 (2% paediatric patients. The acute case fatality rate (CFR during hospital admission was 73/617 (12% in adults and to 42/624 (7% in children. CONCLUSIONS: Zoonotic bacterial and viral pathogens are the most common causes of CNS infection in adults and children in Viet Nam.

  19. Phylogeny and biogeography of Poecilia (Cyprinodontiformes: Poeciliinae) across Central and South America based on mitochondrial and nuclear DNA markers.

    Science.gov (United States)

    Ho, Adeljean L F C; Pruett, Christin L; Lin, Junda

    2016-08-01

    Poeciliids are a diverse group of small Neotropical fishes, and despite considerable research attention as models in ecology and evolutionary biology, our understanding of their biogeographic and phylogenetic relationships is still limited. We investigated the phylogenetic relationships of South and Central American Poecilia, by examining 2395 base pairs of mitochondrial DNA (ATPase 8/6, COI) and nuclear DNA (S7) for 18 species across six subgenera. Fifty-eight novel sequences were acquired from newly collected specimens and 20 sequences were obtained from previously published material. Analyses of concatenated and partitioned mitochondrial DNA and nuclear DNA sets resulted in a well-supported phylogeny that resolved several monophyletic groups corresponding to previously hypothesized subgenera and species complexes. A divergence-dating analysis supported the hypothesis of the genus Poecilia dispersing into Central America in the early Pliocene (ancestors of Psychropoecilia+Allopoecilia+Mollienesia: 7.3-2.0Mya) from predominantly South America. Subsequently, one lineage (subgenus Allopoecilia: 5.1-1.3Mya) expanded deeper into South America from Lower-Central America, and one lineage expanded from Nuclear-Central America into South America (subgenus Mollienesia: 0.71-0.14Mya). The subgenus Mollienesia diverged into three monophyletic groups that can be identified by nuptial male dorsal fin morphology and inner jaw dentition. A subclade of the unicuspid short-fins (subgenus Mollienesia) was the lineage that expanded into South America during the middle Pleistocene. Species in this subclade are now distributed across northern South America, where they are partially sympatric with Allopoecilia. However the P. (A.) caucana complex was not monophyletic, with P. (A.) wandae clustering in the Mollienesia subclade that expanded into South America. It is apparent that characters (body size, scale count, pigmentation, and gonopodium morphology) used to define the P. (A

  20. Endodontic and periodontal management of a severely affected maxillary lateral incisor having combined mucosal fenestration and palatogingival groove

    Directory of Open Access Journals (Sweden)

    Sarang Sharma

    2015-01-01

    Full Text Available Mucosal fenestrations, wherein the tooth root apices are clinically discernible in the oral cavity subsequent to loss of overlying alveolar bone and mucosa, are rare pathologic entities. Palato gingival grooves- anatomic aberrations are also infrequent occurrences that notoriously predispose to periodontal pathologies of varying extent. Both conditions independently are known to popularly affect maxillary lateral incisors. Coexistent fenestration defect and palato gingival groove in the same tooth is extremely rare and undoubtedly is a perfect combination to precipitate severe endodontic-periodontal consequences. In this report, a 34-year-old patient presented to the dental department with complaint of esthetics in relation to exposed root of right maxillary lateral incisor. On closer inspection, a palato gingival groove in addition to fenestration defect was evident on the root surface along with a periodontal pocket of >5 mm. An interdisciplinary treatment was instituted which included endodontic treatment followed by root end resection, osseous bone graft placement and guided tissue regeneration procedures for repair of mucosal fenestration defect. Debridement of the palatal pocket, with saucerization of the groove and restoration with glass ionomer cement were simultaneously employed to correct the palatal defect.

  1. Fluoride uptake into the developing enamel and dentine of sheep incisors following daily ingestion of fluoridated milk or water

    International Nuclear Information System (INIS)

    The caries preventive action of fluoride is common knowledge, although some of the mechanisms involved remain equivocal. At present, raised local levels of fluoride at, or in, the surface of tooth enamel is the most commonly accepted explanation of the anti-cariogenic action of fluoride. However, fluoride incorporated as fluorapatite into the tooth during its formation remains a possible alternative or complementary anti-cariogenic mechanism. If so, regular ingestion of fluoride during tooth formation is beneficial. Although use of fluoridated water is the preferred method in public health programmes, access to suitable potable water is required, and often this in not feasible. Fresh, preserved, or dried cow's milk products are widely used as nutritional and dietary items in most populations, particularly for young children. Milk is a practical, controllable means for regular delivery of fluoride. Processing of milk is commonly centralised and uses standardised conditions, allowing easy supplementation of fluoride for distribution to communities. The purpose of this study was to resolve the question of availability of fluoride ingested in milk compared with fluoride ingested in water by measuring fluoride deposition in the developing permanent incisors of young sheep. Incisors were analysed using a proton microprobe. (author). 18 refs., 1 tabs., 3 figs

  2. Mineral trioxide aggregate apical plug method for the treatment of nonvital immature permanent maxillary incisors: Three case reports

    Directory of Open Access Journals (Sweden)

    Betül Günes

    2012-01-01

    Full Text Available Treatment of nonvital immature permanent teeth with calcium-hydroxide is associated with some difficulties such as weakened tooth fracture, root canal reinfection and long treatment time. Mineral trioxide aggregate (MTA apical plug method is an alternative treatment option for open apices, and has gained popularity in the recent times. In this case report, we have attempted to present successful treatment of three maxillary incisors with open apices and periapical lesions with MTA. After preparing the access cavity, the working length was determined. The root canals were irrigated with 2.5% Sodium hypochlorite (NaOCl and disinfected with calcium-hydroxide for two weeks. MTA was then placed in the apical 3 millimeters of the root canal. The remaining part of the root canal was filled with gutta-percha and the coronal restoration was finished with composite resin. After six months the radiographic examination showed a decrease of periapical lesions. At a 1-year and 18-months follow up, radiological and clinical successful healing of the incisor teeth was seen. MTA seems as an effective material for the apical plug method for the treatment of nonvital immature permanent teeth with open apices.

  3. Micro-CT evaluation of the radioprotective effect of resveratrol on the mandibular incisors of irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Rezende Barbosa, Gabriella Lopes de; Almeida, Solange Maria de, E-mail: gabriellalopes@live.com [Universidade de Campinas (UNICAMP), Piracicaba, SP (Brazil). Escola de Odontologia. Departmento de Diagnostico Oral; Pimenta, Luiz Andre [University of North Carolina at Chapel Hill, School of Dentistry, Department of Dental Ecology, Chapel Hill, NC (United States)

    2016-05-01

    The purpose of this study was to perform a micro computerized tomographic evaluation of the radioprotective effect of resveratrol on the volume of mandibular incisors of irradiated rats. A second aim was to make a quantitative assessment of the effect of x-ray exposure on these dental tissues. Twenty adult male rats were divided into four groups: control, irradiated control, resveratrol, and irradiated resveratrol. The resveratrol groups received 100 mg/kg of resveratrol, whereas the irradiated groups were exposed to 15 Gy of irradiation. The animals were sacrificed 30 days after the irradiation procedure, and their mandibles were removed and scanned in a micro computerized tomography unit. The images were loaded into Mimics software to allow segmentation of the mandibular incisor and assessment of its volume. The results were compared by One-way ANOVA and Tukey's post hoc test, considering a 5% significance level. The irradiated groups showed significantly diminished volumes of the evaluated teeth, as compared with the control group (p < 0.05). The resveratrol group presented higher values than those of the irradiated groups, and volumes similar to those of the control group. High radiation doses significantly affected tooth formation, resulting in alterations in the dental structure, and thus lower volumes. Moreover, resveratrol showed no effective radioprotective impact on dental tissues. Future studies are needed to evaluate different concentrations of this substance, in an endeavor to verify its potential as a radioprotector for these dental tissues. (author)

  4. Micro-CT evaluation of the radioprotective effect of resveratrol on the mandibular incisors of irradiated rats

    Directory of Open Access Journals (Sweden)

    Gabriella Lopes DE REZENDE BARBOSA

    2016-01-01

    Full Text Available Abstract The purpose of this study was to perform a microcomputed tomographic evaluation of the radioprotective effect of resveratrol on the volume of mandibular incisors of irradiated rats. A second aim was to make a quantitative assessment of the effect of x-ray exposure on these dental tissues. Twenty adult male rats were divided into four groups: control, irradiated control, resveratrol, and irradiated resveratrol. The resveratrol groups received 100 mg/kg of resveratrol, whereas the irradiated groups were exposed to 15 Gy of irradiation. The animals were sacrificed 30 days after the irradiation procedure, and their mandibles were removed and scanned in a microcomputed tomography unit. The images were loaded into Mimics software to allow segmentation of the mandibular incisor and assessment of its volume. The results were compared by One-way ANOVA and Tukey’s post hoc test, considering a 5% significance level. The irradiated groups showed significantly diminished volumes of the evaluated teeth, as compared with the control group (p < 0.05. The resveratrol group presented higher values than those of the irradiated groups, and volumes similar to those of the control group. High radiation doses significantly affected tooth formation, resulting in alterations in the dental structure, and thus lower volumes. Moreover, resveratrol showed no effective radioprotective impact on dental tissues. Future studies are needed to evaluate different concentrations of this substance, in an endeavor to verify its potential as a radioprotector for these dental tissues.

  5. Stem and Progenitor Cell-Based Therapy of the Central Nervous System

    DEFF Research Database (Denmark)

    Goldman, Steven A

    2016-01-01

    A variety of neurological disorders are attractive targets for stem and progenitor cell-based therapy. Yet many conditions are not, whether by virtue of an inhospitable disease environment, poorly understood pathophysiology, or poor alignment of donor cell capabilities with patient needs. Moreover......, some disorders may be medically feasible targets but are not practicable, in light of already available treatments, poor risk-benefit and cost-benefit profiles, or resource limitations. This Perspective seeks to define those neurological conditions most appropriate for cell replacement therapy...

  6. The application of fuzzy-based methods to central nerve fiber imaging

    DEFF Research Database (Denmark)

    Axer, Hubertus; Jantzen, Jan; Keyserlingk, Diedrich Graf v.;

    2003-01-01

    This paper discusses the potential of fuzzy logic methods within medical imaging. Technical advances have produced imaging techniques that can visualize structures and their functions in the living human body. The interpretation of these images plays a prominent role in diagnostic and therapeutic....... Fuzzy logic methods were applied to analyze these pictures from low- to high-level image processing. The solutions presented here are motivated by problems of routine neuroanatomic research demonstrating fuzzy-based methods to be valuable tools in medical image processing....

  7. A role for fragment-based drug design in developing novel lead compounds for central nervous system targets

    Directory of Open Access Journals (Sweden)

    Michael J. Wasko

    2015-09-01

    Full Text Available Hundreds of millions of U.S. dollars are invested in the research and development of a single drug. Lead compound development is an area ripe for new design strategies. Therapeutic lead candidates have been traditionally found using high-throughput in vitro pharmacologic screening, a costly method for assaying thousands of compounds. This approach has recently been augmented by virtual screening, which employs computer models of the target protein to narrow the search for possible leads. A variant of virtual screening is fragment-based drug design, an emerging in silico lead discovery method that introduces low molecular weight fragments, rather than intact compounds, into the binding pocket of the receptor model. These fragments serve as starting points for growing the lead candidate. Current efforts in virtual fragment-based drug design within central nervous system (CNS targets are reviewed, as is a recent rule-based optimization strategy in which new molecules are generated within a 3D receptor binding pocket using the fragment as a scaffold. This process places special emphasis on creating synthesizable molecules but also exposes computational questions worth addressing. Fragment-based methods provide a viable, relatively low-cost alternative for therapeutic lead discovery and optimization that can be applied to CNS targets to augment current design strategies.

  8. Prevalence of tics in schoolchildren in central Spain: a population-based study.

    Science.gov (United States)

    Cubo, Esther; Gabriel y Galán, José María Trejo; Villaverde, Vanesa Ausín; Velasco, Sara Sáez; Benito, Vanesa Delgado; Macarrón, Jesús Vicente; Guevara, José Cordero; Louis, Elan D; Benito-León, Julián

    2011-08-01

    Tic disorders constitute a neurodevelopmental disorder of childhood. This study sought to determine the prevalence of tic disorders in a school-based sample. A randomized sample of 1158 schoolchildren, based on clusters (classrooms) in the province of Burgos (Spain), was identified on a stratified sampling frame combining types of educational center and setting (mainstream schools and special education), using a two-phase approach (screening and diagnosis ascertainment by a neurologist). Tics with/without impairment criterion were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders criteria. In mainstream schools, tics were observed in 125/741 students (16.86%; 95% confidence interval, 14.10-19.63), and were more frequent in boys (87/448, 19.42%; 95% confidence interval, 15.64-23.19) compared with girls (38/293, 12.96%; 95% confidence interval, 8.95-16.98; P = 0.03). In special education centers, tics disorders were observed in 11/54 of children (20.37%; 95% confidence interval, 8.70-32.03). Overall, tics with impairment criteria were less frequent than tics without impairment criteria (4.65% vs 11.85%, P tics (6.07%) and Tourette syndrome (5.26%). Tic disorders are common in childhood, and the use or nonuse of impairment criteria exerts a significant impact on tic prevalence estimates. PMID:21763950

  9. Cladistics of some rattans (Calamus spp. from Central Sulawesi based on physical and mechanical characteristic of stems

    Directory of Open Access Journals (Sweden)

    ANDI TANRA TELLU

    2006-07-01

    Full Text Available The research of the physical and mechanical characteristic of rattans stem of 10 species of the genus Calamus from Bancea Nature Reserve and Lore Lindu National Park in Central Sulawesi had been conducted. The aims of this research were to describe phylogenetic relationship of those species based on physical and mechanical characteristic with cladistic approach (cladogram. The research had been used descriptive method, i.e. specific gravity, parallel attracting firmness of fiber, firmness stress parallels of flex firmness, and fiber/static curve. It was reconciled with standard of ASTM D no 143-52 with a few which has modified. The data was analyzed by ANOVA. The result indicated that the mechanical and physical characteristic of Calamus rattan can be made as distinguishing evidences. It can be compiled by a new classification in the form of cladistic (classification of numeric as complement of previous classification.

  10. Thanetian transgressive-regressive sequences based on foraminiferal paleobathymetry at Gebel Matulla, west-central Sinai, Egypt

    Science.gov (United States)

    Farouk, Sherif; Elamri, Zaineb; El-Sorogy, Abdelbaset

    2016-09-01

    Qualitative and quantitative analysis of Thanetian foraminiferal assemblages at Gebel Matulla in west-central Sinai has been carried out. Three benthic foraminiferal assemblages are recorded from shallowest to deepest as Cibicidoides pseudoacutus, Angulogavelinella avnimelechi, Gavelinella danica witch evidences of fluctuations from middle neritic to upper bathyal environments. Changes in the foraminiferal population enabled us to classify the Thanetian succession into two fourth order transgressive-regressive (T-R) sequences. Three sequence boundaries are identified, at the Selandian/Thanetian (S/T) boundary, within the Thanetian succession, and the Paleocene/Eocene (P/E) boundary. It occurs at the top part of the maximum regression associated with major discontinuities and changes in depositional regimes as well as vertical facies changes. Broad correlation with eustatic records based upon integrated microplanktonic biostratigraphy suggests that the fluctuations of foraminiferal population were controlled by global sea-level changes.

  11. Converting Nonliquid Crystals into Liquid Crystals by N-Methylation in the Central Linker of Triazine-Based Dendrimers.

    Science.gov (United States)

    Tsai, Meng-Jung; Hsieh, Jei-Way; Lai, Long-Li; Cheng, Kung-Lung; Liu, Shih-Hsien; Lee, Jey-Jau; Hsu, Hsiu-Fu

    2016-06-17

    Two triazine-based dendrimers were successfully prepared in 60-75% yields. These newly prepared dendrimers 2a and 2b containing the -NMe(CH2)2NMe- and the -NMe(CH2)4NMe- linkers between two G3 dendrons, respectively, exhibit columnar phases during the thermal process. However, the corresponding dendrimers 1a and 1b containing the -NH(CH2)2NH- and the -NH(CH2)4NH- linkers between two G3 dendrons, respectively, do not show any LC phases on thermal treatment. Computational investigations on molecular conformations reveal that N-methylation of the dendritic central linker leads dendrimers to possess more isomeric conformations and thus successfully converts non-LC dendrimers (1a and 1b) into LC dendrimers (2a and 2b). PMID:27203100

  12. Centrally controlled self-healing wavelength division multiplexing passive optical network based on optical carrier suppression technique

    Science.gov (United States)

    Zhu, Min; Zhang, Jiao; Sun, Xiaohan

    2015-12-01

    We proposed and demonstrated a centrally controlled and self-healing wavelength division multiplexing passive optical network with colorless optical network units (ONUs) based on optical carrier suppression technique. By switching the affected data in the OCS signal sideband to an alternate protection path, only one optical switch is provisioned at the optical line terminal, which is controlled by a logic control circuit upon monitoring of power outage on the working path. The proposed scheme can reliably protect against both distribution and feeder fiber failures. Moreover, gain-saturated reflective semiconductor optical amplifiers are used as colorless transmitters in ONUs. The protection scheme feasibility and system performances are experimentally verified with 10 Gb/s downstream and 1.25 Gb/s upstream data in both working and protection modes. The protection switching time was measured to be around 1 ms.

  13. Profile of adults seeking voluntary HIV testing and counseling in rural Central India: results from a hospital-based study.

    Science.gov (United States)

    Pai, Nitika Pant; Joshi, Rajnish; Moodie, Erica E M; Taksande, Bharati; Kalantri, S P; Pai, Madhukar; Tulsky, Jacqueline P; Reingold, Arthur

    2009-03-01

    Rural India has an undetected load of HIV-positive individuals. Few rural adults present for HIV testing and counseling due to stigma, discrimination, and fear of social ostracization. In this rural hospital clinic-based study, we document profiles of rural adults seeking voluntary testing and counseling, and analyze correlates of HIV seropositivity. This cross-sectional study was conducted in 450 participants presenting to the outpatient clinics of Mahatma Gandhi Institute of Medical Sciences, Sevagram, Central India. After informed consent, pre- and post-test counseling, HIV testing, and face-to-face interviews were conducted. Data were collected using a structured questionnaire. The median age of the 450 study participants was 34 years (range 18-88 years); the majority (74%) was married. The overall proportion of HIV seropositivity was 32% [95% CI 28%, 37%]. The proportions of HIV seropositivity in married women, married men, and single men were 41%, 37%, 18%, respectively. No single woman was found seropositive in the study. Very few married women were aware of their husbands' HIV status. In a multivariate analysis, correlates of HIV seropositivity in men were: age 30-39 years, being married, having sex with multiple partners, use of alcohol before sex, and testing positive for HIV in the past. In married women, the only predictor of seropositivity was being married. Although limited by the non-random nature of the sampling method, this pilot study is unique in that it is the first from this rural region of Central India. It provides baseline data on marginalized, largely unstudied populations that may aid in designing probabilistic community-based surveys in this neglected population.

  14. Chordoma versus chondrosarcoma of the central skull base: MR and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Guk Myeong; Han, Moon Hee; Chang, Kee Hyun; Kim, Hong Dae; Yeon, Kyung Mo [Seoul National Univ. (Korea, Republic of). Coll. of Medicine; Yu, In Kyu [Uulji Hospital, Seoul (Korea, Republic of); Kim, Sam Soo [Boramae Hospital, Seoul (Korea, Republic of)

    1998-02-01

    It is known that due to both their imaging and pathologic features, the accurate differentiation of chondrosarcoma from chordoma is difficult. Through an analysis of MR and CT finding, this study aims to determine the differential points between these two tumors. In 21 patients, CT and MR imaging studies of chordoma (n=12) and chondrosarcoma (n=9) at the base of the skull were retrospectively reviewed. Diagnosis had been established by histologic examination of surgically removed specimens. Eleven of the chordomas were subclassified as conventional and one as chondroid ; eight chondrosarcoma were conventional and one was myxoid. Four chordoma patients underwent CT and MR ; in six, only MR was in one, only CT was performed. All scans were retrospectively evaluated for the location (midline/off-midline), direction of extension, margin and shape, bony destruction and calcification, MR signal intensity and enhancement patterns of the tumors. Degree of calcification was graded from I to II. Although MR and CT findings were similar in both types of tumor, location and degree of calcification may be features which usefully distinguish chordoma from chondrosarcoma. (author). 17 refs., 2 tabs., 5 figs.

  15. Surface displacement based shape analysis of central brain structures in preterm-born children

    Science.gov (United States)

    Garg, Amanmeet; Grunau, Ruth E.; Popuri, Karteek; Miller, Steven; Bjornson, Bruce; Poskitt, Kenneth J.; Beg, Mirza Faisal

    2016-03-01

    Many studies using T1 magnetic resonance imaging (MRI) data have found associations between changes in global metrics (e.g. volume) of brain structures and preterm birth. In this work, we use the surface displacement feature extracted from the deformations of the surface models of the third ventricle, fourth ventricle and brainstem to capture the variation in shape in these structures at 8 years of age that may be due to differences in the trajectory of brain development as a result of very preterm birth (24-32 weeks gestation). Understanding the spatial patterns of shape alterations in these structures in children who were born very preterm as compared to those who were born at full term may lead to better insights into mechanisms of differing brain development between these two groups. The T1 MRI data for the brain was acquired from children born full term (FT, n=14, 8 males) and preterm (PT, n=51, 22 males) at age 8-years. Accurate segmentation labels for these structures were obtained via a multi-template fusion based segmentation method. A high dimensional non-rigid registration algorithm was utilized to register the target segmentation labels to a set of segmentation labels defined on an average-template. The surface displacement data for the brainstem and the third ventricle were found to be significantly different (p preterm birth.

  16. Beyond the Central Dogma: Model-Based Learning of How Genes Determine Phenotypes.

    Science.gov (United States)

    Reinagel, Adam; Bray Speth, Elena

    2016-01-01

    In an introductory biology course, we implemented a learner-centered, model-based pedagogy that frequently engaged students in building conceptual models to explain how genes determine phenotypes. Model-building tasks were incorporated within case studies and aimed at eliciting students' understanding of 1) the origin of variation in a population and 2) how genes/alleles determine phenotypes. Guided by theory on hierarchical development of systems-thinking skills, we scaffolded instruction and assessment so that students would first focus on articulating isolated relationships between pairs of molecular genetics structures and then integrate these relationships into an explanatory network. We analyzed models students generated on two exams to assess whether students' learning of molecular genetics progressed along the theoretical hierarchical sequence of systems-thinking skills acquisition. With repeated practice, peer discussion, and instructor feedback over the course of the semester, students' models became more accurate, better contextualized, and more meaningful. At the end of the semester, however, more than 25% of students still struggled to describe phenotype as an output of protein function. We therefore recommend that 1) practices like modeling, which require connecting genes to phenotypes; and 2) well-developed case studies highlighting proteins and their functions, take center stage in molecular genetics instruction. PMID:26903496

  17. Climate Based Façade Design for Business Buildings with Examples from Central London

    Directory of Open Access Journals (Sweden)

    John Napier

    2015-01-01

    Full Text Available There is a disconnection between commercial architecture and environmental thinking, where green features can be included as part of a strategy for gaining approvals and marketing projects, but those features are not reviewed after completion and occupation of the building and knowledge is not shared. High levels of air conditioning are still considered unavoidable. Elaborate double skin façades and complex motorized shading systems are adopted; often masking an underlying lack of basic environmental thinking. This article returns (in principle to the physics of comfort in buildings and the passive strategies which can help achieve this with a low energy and carbon footprint. Passive and active façade design strategies are outlined as the basis of a critical tool and a design methodology for new projects. A new architectural sensibility can arise based on modeling the inputs of sunlight, daylight and air temperature in time and space at the early stages of design. Early but sound strategies can be tested and refined using advanced environmental modeling techniques. Architecture and environmental thinking can proceed hand in hand through the design process.

  18. ScienceCentral: open access full-text archive of scientific journals based on Journal Article Tag Suite regardless of their languages

    OpenAIRE

    Huh, Sun

    2013-01-01

    ScienceCentral, a free or open access, full-text archive of scientific journal literature at the Korean Federation of Science and Technology Societies, was under test in September 2013. Since it is a Journal Article Tag Suite-based full text database, extensible markup language files of all languages can be presented, according to Unicode Transformation Format 8-bit encoding. It is comparable to PubMed Central: however, there are two distinct differences. First, its scope comprises all scienc...

  19. Is violence associated with increased risk behavior among MSM? Evidence from a population-based survey conducted across nine cities in Central America

    OpenAIRE

    Wheeler, Jennifer; Anfinson, Katherine; Valvert, Dennis; Lungo, Susana

    2014-01-01

    Background/Objective: There is a dearth of research examining the linkages between violence and HIV risk behavior among men who have sex with men (MSM), including those who identify as transgender women (TW), particularly in Central America where violence is widespread. In this paper, we use population-based survey results to independently examine the correlations between physical, emotional and sexual violence and HIV risk behavior among MSM populations in five countries in Central America.D...

  20. Simulation Platform of Underwater Quadruped Walking Robot Based on MotionGenesis Kane 5 3 and Central Pattern Generator

    Institute of Scientific and Technical Information of China (English)

    Ke Yang; XuYang Wang; Tong Ge; Chao Wu

    2014-01-01

    It will still in lack of a simulation platform used to learn the walking of underwater quadruped walking robot. In order to alleviate this shortage, a simulation platform for the underwater quadruped walking robot based on Kane dynamic model and CPG-based controller is constructed. The Kane dynamic model of the underwater quadruped walking robot is processed with a commercial package MotionGenesis Kane 5�3. The forces between the feet and ground are represented as a spring and damper. The relation between coefficients of spring and damper and stability of underwater quadruped walking robot in the stationary state is studied. The CPG-based controller consisted of Central Pattern Generator ( CPG) and PD controller is presented, which can be used to control walking of the underwater quadruped walking robot. The relation between CPG parameters and walking speed of underwater quadruped walking robot is investigated. The relation between coefficients of spring and damper and walking speed of underwater quadruped walking robot is studied. The results show that the simulation platform can imitate the stable walking of the underwater quadruped walking robot.

  1. Mapping of leptospirosis risk factor based on remote sensing image in Tembalang, Semarang City, Central Java

    Directory of Open Access Journals (Sweden)

    Sunaryo Sunaryo

    2012-09-01

    of leptospirosis, physical environment of risk factor analysis.Methods: This cross sectional design consisted of 246 leptospirosis subjects mapped with GPS, and processed by using ArcGis 92 program. Leptospirosis case was overlaid with remote sensing (Quickbird image, then is done interpretation of spatial feature, and digitation on screen to visual identify of risk factor.Results: Based on digital visualization leptospirosis cases in 2009 were clustered in Tembalang with shortest distance index 0,009 km and is furthermost 18 km. More case distribution found at children and men adolescent. Temporally, case increased in the dry season, among of July and August. Result of visual interpretation and digitation can obtain land use map, water body, settlement, fl oods area, vegetation index and height.Conclusion: Spatial high resolution remote sensing image is very good for mapping of leptospirosis risk factor. Leptospirosis case distribution forms the cluster in Tembalang; case is predominated by children andmen adolescent. (Health Science Indones 2012;1:45-50 

  2. Reconstruction of Oceanographic Changes Based on the Diatom Records of the Central Okhotsk Sea over the last 500000 Years

    Directory of Open Access Journals (Sweden)

    Wei-Lung Wang and Liang-Chi Wang

    2008-01-01

    Full Text Available This study provides insight into changes in sea ice conditions and the oceanographic environment over the past 500 kyr through analysis of the diatom record. Based on the relative abundance of 13 diatoms species in piston core MD012414, four types of environmental conditions in the central Okhotsk Sea over the last 330 ka BP have been distinguished: (1 open-ocean alternating with seasonal sea-ice cover in Stages 9, 5, and 1; (2 almost open-ocean free of sea-ice cover in Stages 7 and 3; (3 perennial sea-ice cover in Stages 6, 4, and 2; and (4 a warm ice-age dominated by open ocean assemblages in Stage 8. The littoral diatom species, Paralia sulcata, showed a sudden increase from the glacial period to the nterglacial period over the last 330 ka BP, except during Stage 8. Such a result implies that melting sea-ice transported terrigenous materials from the north Okhotsk Sea continental shelves to the central ocean during eglaciation. From Stage 13 to Stage 10, however, cold and warm marine conditions unexpectedly occurred in the late interglacial periods and the glacial periods, respectively. One possible reason for this is a lack of age control points from Stage 13 to Stage 10, and the different sediment accumulation rates between glacial and interglacial periods. This study suggests not only the process by which oceanographic variation of sea ice occurred, but also new significance for Paralia sulcata as an indicator in the diatom record of the Okhotsk Sea.

  3. Conditional Knockout of the MicroRNA 17-92 Cluster in Type-I Collagen-Expressing Cells Decreases Alveolar Bone Size and Incisor Tooth Mechanical Properties.

    Science.gov (United States)

    Ibrahim, M; Mohan, S; Xing, M J; Kesavan, C

    2016-01-01

    To test the role of the miR17-92 (miR) cluster in dental bones, we evaluated the incisor tooth phenotype by micro-CT in 5- and 12-week-old conditional knockout (CKO) mice deficient in the miR17-92 cluster in type-I collagen-expressing cells and bone strength by finite element analysis. The incisor teeth of CKO mice showed a 23-30 % reduction in tissue volume and bone volume. Accordingly, the stiffness and failure load of incisor teeth assessed by finite element analysis showed an 18-40 % decrease in CKO compared to wild-type mice. A positive correlation between bone parameters and strength data suggests that the decreased mechanical properties of incisor teeth are due to decreased tissue volume and bone volume. Subsequently, we found that the width of alveolar bone was reduced by 25 % with a 16 % increase in periodontal ligament space, suggesting that the CKO mice are more susceptible to tooth movement. Since alveolar bone is populated primarily by osteoblast lineage cells, it is likely that the reduction in periosteal expansion of alveolar bone in the lower jaw of CKO mice results from decreased periosteal bone formation. Overall, our phenotype analysis demonstrates that the miR17-92 cluster is essential for development and maintenance of tooth strength by regulating its tooth size.

  4. The effect of partial damage to the enamel-related periodontium combined with root resection on eruption of the rat incisor eruption.

    Science.gov (United States)

    Merzel, José; Nunes, Silvana F; Novaes, Pedro D

    2004-03-01

    Previous work has indicated that the enamel-related periodontium (ERP) has a role in the eruptive process of the rat lower incisor. By combining partial damage of this tissue with resection of the odontogenic organ, we examined the effect of the damage on subsequent incisor eruption. The connective tissue of the enamel-related periodontium was regenerated in less than 2 weeks, showing morphology close to normal. The injured part of the enamel organ was neither regenerated nor repaired, and a cement-like tissue, continuous with the true acellular cement, was formed on the denuded enamel. Before tooth exfoliation, the operated teeth erupted at a slower rate compared with root-resected and sham-operated incisors, probably because of the absence of a substantial part of the enamel organ due to surgical damage. As with the coronal dental follicle and the enamel organ in rat molars, the enamel-related periodontium and the enamel organ of rat incisors may have some control on their eruptive process. PMID:14725812

  5. Conditional Knockout of the MicroRNA 17-92 Cluster in Type-I Collagen-Expressing Cells Decreases Alveolar Bone Size and Incisor Tooth Mechanical Properties.

    Science.gov (United States)

    Ibrahim, M; Mohan, S; Xing, M J; Kesavan, C

    2016-01-01

    To test the role of the miR17-92 (miR) cluster in dental bones, we evaluated the incisor tooth phenotype by micro-CT in 5- and 12-week-old conditional knockout (CKO) mice deficient in the miR17-92 cluster in type-I collagen-expressing cells and bone strength by finite element analysis. The incisor teeth of CKO mice showed a 23-30 % reduction in tissue volume and bone volume. Accordingly, the stiffness and failure load of incisor teeth assessed by finite element analysis showed an 18-40 % decrease in CKO compared to wild-type mice. A positive correlation between bone parameters and strength data suggests that the decreased mechanical properties of incisor teeth are due to decreased tissue volume and bone volume. Subsequently, we found that the width of alveolar bone was reduced by 25 % with a 16 % increase in periodontal ligament space, suggesting that the CKO mice are more susceptible to tooth movement. Since alveolar bone is populated primarily by osteoblast lineage cells, it is likely that the reduction in periosteal expansion of alveolar bone in the lower jaw of CKO mice results from decreased periosteal bone formation. Overall, our phenotype analysis demonstrates that the miR17-92 cluster is essential for development and maintenance of tooth strength by regulating its tooth size. PMID:27643583

  6. Acleotrema lamothei n. sp. (Monogenea: Diplectanidae from the gills of Kyphosus incisor in Brazilian waters Acleotrema lamothei n. sp. (Monogenea: Diplectanidae de las branquias de Kyphosus incisor en aguas brasileñas

    Directory of Open Access Journals (Sweden)

    Cláudia P. Santos

    2008-08-01

    Full Text Available A diplectanid monogenean, Acleotrema lamothei n. sp., is described from the gills of the yellow sea chub Kyphosus incisor (Cuvier, 1831 in Brazilian waters off Rio de Janeiro State. This species is distinguished by the facts that the male copulatory organ is armed with spines throughout most of its length, the ventral hamuli have a very long, stout outer root, which is slightly notched proximally, an inner root less than half the length of the outer root and a fine blade and point. It also differs from most species of the genus by the greater size of the haptor and its hard parts. This is the first record of a species of Acleotrema Johnston and Tiegs, 1922 from South American waters.Se describe Acleotrema lamothei n. sp. de las branquias del pez Kyphosus incisor (Cuvier, 1831 recolectado en las costas del estado de Río de Janeiro, Brasil. La nueva especie se distingue por la armadura del órgano copulador con espinas en casi toda su longitud, por la presencia de una raíz externa larga y robusta en el hámuli ventral, provista de una pequeña muesca proximal, por la raíz interna que mide menos de la mitad de la longitud de la externa y por tener la hoja y la punta finas. Asimismo, difiere de muchas de las especies del género por el gran tamaño del haptor y de sus partes esclerozadas. El presente constituye el primer registro de una especie de Acleotrema Johnston y Tiegs, 1922 en aguas sudamericanas.

  7. The optimal fractional S transform of seismic signal based on the normalized second-order central moment

    Science.gov (United States)

    Wang, Yuqing; Peng, Zhenming

    2016-06-01

    As the extension of time-bandwidth product (TBP) in the fractional domain, the generalized time-bandwidth product (GTBP) provides a rotation-independent measure of compactness. A new fractional S transform (FrST) is proposed to avoid missing the physical meaning of the fractional time-frequency plane. FrST is based on the GTBP criterion and the time-frequency rotation property of fractional Fourier transform (FrFT). In addition, we introduce the normalized second-order central moment (NSOCM) calculation method to determine the optimal order. The optimal order searching process can be converted into the NSOCM calculation. Compared with TBP search algorithms, the NSOCM approach has higher computational efficiency. The qualitative advantage of the NSOCM approach in the optimal order selection is demonstrated by a series of model tests. The optimal FrST based on NSOCM (OFrST) can produce more compact time-frequency support than the S transform. The real seismic data spectral decomposition results show that the proposed algorithm can obtain single-frequency visualization with better time-frequency concentration, thereby enhancing the precision of reservoir prediction.

  8. A central support system can facilitate implementation and sustainability of a Classroom-based Undergraduate Research Experience (CURE) in Genomics.

    Science.gov (United States)

    Lopatto, David; Hauser, Charles; Jones, Christopher J; Paetkau, Don; Chandrasekaran, Vidya; Dunbar, David; MacKinnon, Christy; Stamm, Joyce; Alvarez, Consuelo; Barnard, Daron; Bedard, James E J; Bednarski, April E; Bhalla, Satish; Braverman, John M; Burg, Martin; Chung, Hui-Min; DeJong, Randall J; DiAngelo, Justin R; Du, Chunguang; Eckdahl, Todd T; Emerson, Julia; Frary, Amy; Frohlich, Donald; Goodman, Anya L; Gosser, Yuying; Govind, Shubha; Haberman, Adam; Hark, Amy T; Hoogewerf, Arlene; Johnson, Diana; Kadlec, Lisa; Kaehler, Marian; Key, S Catherine Silver; Kokan, Nighat P; Kopp, Olga R; Kuleck, Gary A; Lopilato, Jane; Martinez-Cruzado, Juan C; McNeil, Gerard; Mel, Stephanie; Nagengast, Alexis; Overvoorde, Paul J; Parrish, Susan; Preuss, Mary L; Reed, Laura D; Regisford, E Gloria; Revie, Dennis; Robic, Srebrenka; Roecklien-Canfield, Jennifer A; Rosenwald, Anne G; Rubin, Michael R; Saville, Kenneth; Schroeder, Stephanie; Sharif, Karim A; Shaw, Mary; Skuse, Gary; Smith, Christopher D; Smith, Mary; Smith, Sheryl T; Spana, Eric P; Spratt, Mary; Sreenivasan, Aparna; Thompson, Jeffrey S; Wawersik, Matthew; Wolyniak, Michael J; Youngblom, James; Zhou, Leming; Buhler, Jeremy; Mardis, Elaine; Leung, Wilson; Shaffer, Christopher D; Threlfall, Jennifer; Elgin, Sarah C R

    2014-01-01

    In their 2012 report, the President's Council of Advisors on Science and Technology advocated "replacing standard science laboratory courses with discovery-based research courses"-a challenging proposition that presents practical and pedagogical difficulties. In this paper, we describe our collective experiences working with the Genomics Education Partnership, a nationwide faculty consortium that aims to provide undergraduates with a research experience in genomics through a scheduled course (a classroom-based undergraduate research experience, or CURE). We examine the common barriers encountered in implementing a CURE, program elements of most value to faculty, ways in which a shared core support system can help, and the incentives for and rewards of establishing a CURE on our diverse campuses. While some of the barriers and rewards are specific to a research project utilizing a genomics approach, other lessons learned should be broadly applicable. We find that a central system that supports a shared investigation can mitigate some shortfalls in campus infrastructure (such as time for new curriculum development, availability of IT services) and provides collegial support for change. Our findings should be useful for designing similar supportive programs to facilitate change in the way we teach science for undergraduates. PMID:25452493

  9. Optimization of the preparation of sonogenic phospholipids-based microbubbles by using central composite experimental design and response surface methodology.

    Science.gov (United States)

    Zhao, Ying-Zheng; Lu, Cui-Tao; Mei, Xin-Guo

    2008-08-01

    Sonogenic microbubble agent is a newly developed drug targeting delivery system, which uses ultrasonic beam to enhance the delivery of drug and gene to targeted cells and tissues. In this paper, the preparation of sonogenic phospholipids-based microbubbles was optimized by using central composite experimental design (CCD) and response surface methodology (RSM). Hydrogenated egg phosphatidylcholine (EPC), Tween 80 and polyethylene glycol 1500 (PEG 1500) were important components affecting the concentration of 2 - 8 microm microbubbles in the preparation. The combined effects of these three factors were analyzed by CCD and optimized by RSM. Evaluation variable was the concentration of 2 - 8 microm microbubbles. Overall desirability was fitted to a second-order polynomial equation, through which three dimensional response surface graphs were produced. Optimal experimental conditions were selected from the stationary point of the response surfaces. The stability of the sonogenic phospholipids-based microbubbles by the optimal formulation was investigated by accelerated experiment. The contrast effect in vivo of the optimal formulation was investigated. Foreign market product SonoVue was used as the control. From the results, all the three factors had positive effects on the concentration of 2 - 8 microm microbubbles. The optimal condition in the preparation of phospholipids-based microbubbles was obtained as following: EPC 8.35 mg, Tween 80 21.68 mg and PEG 1500 201 mg. The mean value of the concentration of 2 - 8 microm microbubbles in rechecking experiment reached 8.60 x 10(9) x mL(-1). From the accelerated experiment, phospholipids-based microbubbles showed good physical stability. The intensity (relative unit) and duration of the contrast effect by the optimal formulation were 4.47 +/- 0.15 and (302 +/- 7) s respectively, which showed little difference with foreign market product SonoVue [4.28 +/- 0.13, (309 +/- 8) s]. The optimal formulation selected by CCD and

  10. Calculation of centrality bias factors in $p$+A collisions based on a positive correlation of hard process yields with underlying event activity

    CERN Document Server

    Perepelitsa, Dennis V

    2014-01-01

    Hard scattering yields in centrality-selected proton-- and deuteron--nucleus ($p$+A) collisions are generally compared to nucleon--nucleon ($NN$) cross-sections scaled to the appropriate partonic luminosity using geometric models derived from an analysis of minimum bias $p$+A interactions. In general, these models assume that hard process rates and the magnitude of the soft event activity in the underlying $NN$ collisions is uncorrelated. When included, these correlations influence the measured yield in a nominal centrality interval, an effect typically referred to as a "centrality bias". In this work, the impact of a positive correlation between the hard scattering yield and the underlying event activity in individual $NN$ collisions is investigated. This correlation is incorporated into the centrality calculations used by ATLAS and PHENIX, both based on a similar Monte Carlo Glauber approach but with different models of the per-collision or per-participant event activity. It is found that the presence of th...

  11. Application of a process-based shallow landslide hazard model over a broad area in Central Italy

    Science.gov (United States)

    Gioia, Eleonora; Speranza, Gabriella; Ferretti, Maurizio; Godt, Jonathan W.; Baum, Rex L.; Marincioni, Fausto

    2015-01-01

    Process-based models are widely used for rainfall-induced shallow landslide forecasting. Previous studies have successfully applied the U.S. Geological Survey’s Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability (TRIGRS) model (Baum et al. 2002) to compute infiltration-driven changes in the hillslopes’ factor of safety on small scales (i.e., tens of square kilometers). Soil data input for such models are difficult to obtain across larger regions. This work describes a novel methodology for the application of TRIGRS over broad areas with relatively uniform hydrogeological properties. The study area is a 550-km2 region in Central Italy covered by post-orogenic Quaternary sediments. Due to the lack of field data, we assigned mechanical and hydrological property values through a statistical analysis based on literature review of soils matching the local lithologies. We calibrated the model using rainfall data from 25 historical rainfall events that triggered landslides. We compared the variation of pressure head and factor of safety with the landslide occurrence to identify the best fitting input conditions. Using calibrated inputs and a soil depth model, we ran TRIGRS for the study area. Receiver operating characteristic (ROC) analysis, comparing the model’s output with a shallow landslide inventory, shows that TRIGRS effectively simulated the instability conditions in the post-orogenic complex during historical rainfall scenarios. The implication of this work is that rainfall-induced landslides over large regions may be predicted by a deterministic model, even where data on geotechnical and hydraulic properties as well as temporal changes in topography or subsurface conditions are not available.

  12. Actin-Based Motility of Burkholderia thailandensis Requires a Central Acidic Domain of BimA That Recruits and Activates the Cellular Arp2/3 Complex▿

    OpenAIRE

    Sitthidet, Chayada; Stevens, Joanne M; Field, Terence R.; Layton, Abigail N.; Korbsrisate, Sunee; Stevens, Mark P.

    2010-01-01

    Burkholderia species use BimA for intracellular actin-based motility. Uniquely, Burkholderia thailandensis BimA harbors a central and acidic (CA) domain. The CA domain was required for actin-based motility, binding to the cellular Arp2/3 complex, and Arp2/3-dependent polymerization of actin monomers. Our data reveal distinct strategies for actin-based motility among Burkholderia species.

  13. Hybrid Page Scoring Algorithm Based on Centrality and PageRank%基于中心性和PageRank的网页综合评分方法

    Institute of Scientific and Technical Information of China (English)

    乔少杰; 彭京; 李天瑞; 李红; 李太勇; 王超

    2011-01-01

    In order to score Web pages in an effective manner, a new page scoring algorithm, CentralRank, was proposed based on centrality measures, including degree, betweenness and closeness, and the PageRank algorithm. The CentralRank algorithm computes the importance of pages in Web social networks based on the centrality measures and employs the PageRank algorithm to accurately score Web pages. To verify the performance of the CentralRank algorithm, a Web crawler was developed to automatically and effectively crawl Web pages. The Web crawler contains three essential techniques, that is, Web data collection, content analysis and duplicate page detection. Experiments on real data show that the CentralRank algorithm can guarantee less time deficiency and is more exact in scoring Web pages than the centrality measures-based page ranking algorithm and the PageRank algorithm with an average improvement of 14.2% and 7.5% , respectively.%为准确、高效地对网页进行评分,提出了一种基于中心性(结点度、居间度和紧密度)和PageRank算法的网页评分方法CentralRank.它采用PageBank算法计算网页分数,借助中心性度量的方法计算页面在Web社会网络中的重要性.为了验证CentralRank的性能优势,设计了一个网页抓取器,可利用该抓取器自动、准确地下载网页信息.该网页抓取器集成了网络信息采集、页面内容分析和页面消重3项技术.基于大量真实数据的实验结果表明:CentralRank在保证网页评分时间性能的前提下,比单纯基于中心性的网页评分算法和PageBank算法更准确、有效,预测准确性分别提高约14.2%和7.5%.

  14. Modeling and optimization of antibacterial activity of the chitosan-based hydrogel films using central composite design.

    Science.gov (United States)

    Lahooti, Behnaz; Khorram, Mohammad; Karimi, Gholamreza; Mohammadi, Aliakbar; Emami, Amir

    2016-10-01

    In the present study, hydrogel films composed of chitosan-poly(vinyl alcohol)-gelatin-thyme honey were successfully prepared by casting method, and their anti-bacterial properties were modeled and optimized. Antibacterial properties of the prepared films were analyzed by applying agar diffusion method. Staphylococcus aureus and Pseudomonas aeruginosa were tested as Gram-positive and Gram-negative bacteria, respectively. In order to obtain the composition of the film with maximum inhibition zone against both above-mentioned bacterial strains, the experiments were designed using response surface methodology based on five-level central composite design with four parameters, including concentrations of chitosan, poly(vinyl alcohol), gelatin, and honey. The results indicated that the prepared samples had good antibacterial activities against these two studied bacteria strains. Response surface method is conducted to develop mathematical models for process responses. Variance analysis on the experimental data shows that inhibition zone can be predicted effectively with quadratic models. In addition, swelling properties and rate of water vapor transmission of the prepared hydrogel films were studied. Due to the successful results, this hydrogel film has an excellent potential to be explored further as a wound healing material. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2544-2553, 2016. PMID:27241899

  15. Determinants of Cervical Cancer Screening Uptake among Women in Ilorin, North Central Nigeria: A Community-Based Study

    Directory of Open Access Journals (Sweden)

    Ajibola Idowu

    2016-01-01

    Full Text Available Introduction. Cancer of the cervix is the leading cause of cancer deaths among women in developing countries. Screening is one of the most cost effective control strategies for the disease. This study assessed the determinants of cervical cancer screening uptake among Nigerian women. Methodology. This cross-sectional study was conducted using multistage sampling technique among 338 participants in Ilorin, North Central Nigeria. A pretested questionnaire was used for data collection and data analysis was done using SPSS version 21. Chi-square test was used for bivariate analysis while binary logistic regression was used for multivariate analysis. Statistical significance was set at p<0.05. Results. Only 8.0% of the respondents had ever been screened for cancer of the cervix. The proportion of women who had ever been screened was significantly higher among those who demonstrated positive attitude to screening (81.5%, p=0.001, respondents who were aware of the disease (100.0%, p=0.001, and those who were aware of cervical cancer screening (88.9%, p=0.001. Respondents who had negative attitude had 63% lesser odds of being screened compared to those who had positive attitudes towards screening (AOR; 0.37, 95% CI; 0.01–0.28. Conclusion. There is urgent need to improve the knowledge base and attitude of Nigerian women to enhance cervical cancer screening uptake among them.

  16. Central heating plant economic evaluation program. Volume 3. Military base weather information data management program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lin, M.C.; Moshage, R.; Schanche, G.; Blazek, C.; Biederman, R.

    1995-01-01

    Public Law has directed the Department of Defense (DOD) to rehabilitate and convert its existing domestic power plants to burn more coal. Other Federal legislation requires DOD to use the most economic fuel for any new heating system. This five-volume report discusses the Central Heating Plant Economic Evaluation Program (CHPECON), a computer program for screening potential new and retrofit steam/power generation facilities. Volume 1 is the Technical Reference. Volume 2 is the User`s Manual. Volume 3 is the Military Base Weather Information Data Management Program. Volume 4 is the Coalfield Properties Information Data Management Program. Volume 5 is the Emission Regulations Data Management Program. CHPECON provides screening criteria to evaluate competing combustion technologies using coal, gas, or oil; detailed conceptual facility design information; budgetary facility costs; and economic measures of project acceptability including total life cycle costs and levelized cost of service. The program provides sufficient flexibility to vary critical design and operating parameters to determine project sensitivity and parametric evaluation.

  17. Controlling Aedes aegypti population as DHF vector with radiation based-sterile insect technique in Banjarnegara Regency, Central Java

    International Nuclear Information System (INIS)

    The control program of dengue hemorrhagic fever (DHF) in Indonesia is still a problem due to the incomplete integrated handling. Sterile insect technique (SIT) for Aedes aegypti as DHF vector was considered as a potential strategy for controlling the DHF. A preliminary survey was carried out to determine the characteristic of A aegypti population in the study site before the implementation of SIT. The implementation of radiation based-SIT was carried out in Krandegan and Kutabanjar Villages of Banjarnegara Regency, Central Java which involved 99 houses. One hundred gamma rays irradiated male mosquitoes were released to each house up to five times. The eggs, larvae and adult mosquitoes were collected using ovitrap and weekly observed. The initial population density of A. aegypti in the studied area was obtained to be 6 mosquitoes per house with the mean index of house was 15.86% and the mean sterility of sterilized mosquitoes was 79.16%. The SIT effectively reduced A. aegypti population after the fifth release of irradiated mosquitoes into the houses. It can be assumed that the SIT was effective in controlling DHF vector in the studied area, nevertheless, it will be more effective if it is combined with other handling techniques. (author)

  18. Ocular biometry in the adult population in rural central China: a population-based, cross-sectional study

    Institute of Scientific and Technical Information of China (English)

    Ting; Fu; Yin-Wei; Song; Zhi-Qi; Chen; Jun-Wen; He; Kun; Qiao; Xu-Fang; Sun; Hong; Zhang; Jun-Ming; Wang

    2015-01-01

    ·AIM: To describe the distribution and determinants of ocular biometric parameters and to ascertain the relative importance of these determinants in a large population of adults in rural central China.·METHODS: A population-based, cross-sectional study performed in rural central China included 1721 participants aged 40 or more years. Ocular biometrical parameters including axial length(AL), anterior chamber depth(ACD), radius of corneal curvature(K) and horizontal corneal diameter [white-to-white(WTW)distance] were measured using non-contact partial coherence interferometry [intraocular lens(IOL)-Master].·RESULTS: Ocular biometric data on 1721 participants with a average age of 57.0 ±8.7y were analyzed at last.The general mean AL, ACD, mean corneal curvature radius(MCR), WTW were 22.80±1.12, 2.96±0.36, 7.56±0.26 and 11.75 ±0.40 mm, respectively. The mean values of each parameter in 40 to 49, 50 to 59, 60 to 69, and 70 to91 years age groups were as follows: AL, 22.77 ±0.87,22.76 ±1.06, 22.89 ±1.41, 22.92 ±0.80 mm; ACD, 3.10 ±0.32,2.98 ±0.34, 2.86 ±0.36, 2.77 ±0.35 mm; MCR, 7.58 ±0.25,7.54 ±0.26, 7.55 ±0.26, 7.49 ±0.28 mm; WTW, 11.79 ±0.38,11.75 ±0.40, 11.72 ±0.41, 11.67 ±0.41 mm. The AL, ACD,MCR and WTW were correlated with age and the AL was correlated with height and weight.·CONCLUSION: Our findings can serve as an important normative reference for multiple purposes and may help to improve the quality of rural eye care.

  19. Characterisation of Central-African emissions based on MAX-DOAS measurements, satellite observations and model simulations over Bujumbura, Burundi.

    Science.gov (United States)

    Gielen, Clio; Hendrick, Francois; Pinardi, Gaia; De Smedt, Isabelle; Stavrakou, Trissevgeni; Yu, Huan; Fayt, Caroline; Hermans, Christian; Bauwens, Maité; Ndenzako, Eugene; Nzohabonayo, Pierre; Akimana, Rachel; Niyonzima, Sébastien; Müller, Jean-Francois; Van Roozendael, Michel

    2016-04-01

    Central Africa is known for its strong biogenic, pyrogenic, and to a lesser extent anthropogenic emissions. Satellite observations of species like nitrogen dioxide (NO2) and formaldehyde (HCHO), as well as inverse modelling results have shown that there are large uncertainties associated with the emissions in this region. There is thus a need for additional measurements, especially from the ground, in order to better characterise the biomass-burning and biogenic products emitted in this area. We present MAX-DOAS measurements of NO2, HCHO, and aerosols performed in Central Africa, in the city of Bujumbura, Burundi (3°S, 29°E, 850m). A MAX-DOAS instrument has been operating at this location by BIRA-IASB since late 2013. Aerosol-extinction and trace-gases vertical profiles are retrieved by applying the optimal-estimation-based profiling tool bePRO to the measured O4, NO2 and HCHO slant-column densities. The MAX-DOAS vertical columns and profiles are used for investigating the diurnal and seasonal cycles of NO2, HCHO, and aerosols. Regarding the aerosols, the retrieved AODs are compared to co-located AERONET sun photometer measurements for verification purpose, while in the case of NO2 and HCHO, the MAX-DOAS vertical columns and profiles are used for validating GOME-2 and OMI satellite observations. To characterise the biomass-burning and biogenic emissions in the Bujumbura region, the trace gases and aerosol MAX-DOAS retrievals are used in combination to MODIS fire counts/radiative-power and GOME-2/OMI NO2 and HCHO satellite data, as well as simulations from the NOAA backward trajectory model HYSPLIT. First results show that HCHO seasonal variation around local noon is driven by the alternation of rain and dry periods, the latter being associated with intense biomass-burning agricultural activities and forest fires in the south/south-east and transport from this region to Bujumbura. In contrast, NO2 is seen to depend mainly on local emissions close to the city, due

  20. Nanoparticle-based drug delivery to improve the efficacy of antiretroviral therapy in the central nervous system

    Directory of Open Access Journals (Sweden)

    Gomes MJ

    2014-04-01

    Full Text Available Maria João Gomes,1 José das Neves,1,2 Bruno Sarmento1,2 1Instituto de Engenharia Biomédica (INEB, Porto, Portugal; 2Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde (IINFACTS, Instituto Superior de Ciências da Saúde-Norte, CESPU, Gandra, Portugal Abstract: Antiretroviral drug therapy plays a cornerstone role in the treatment of human immunodeficiency virus (HIV/acquired immunodeficiency syndrome patients. Despite obvious advances over the past 3 decades, new approaches toward improved management of infected individuals are still required. Drug distribution to the central nervous system (CNS is required in order to limit and control viral infection, but the presence of natural barrier structures, in particular the blood–brain barrier, strongly limits the perfusion of anti-HIV compounds into this anatomical site. Nanotechnology-based approaches may help providing solutions for antiretroviral drug delivery to the CNS by potentially prolonging systemic drug circulation, increasing the crossing and reducing the efflux of active compounds at the blood–brain barrier, and providing cell/tissue-targeting and intracellular drug delivery. After an initial overview on the basic features of HIV infection of the CNS and barriers to active compound delivery to this anatomical site, this review focuses on recent strategies based on antiretroviral drug-loaded solid nanoparticles and drug nanosuspensions for the potential management of HIV infection of the CNS. Keywords: HIV/AIDS, blood–brain barrier, protease inhibitors, efflux transporters, drug targeting

  1. Mapping hydrological environments in central Amazonia: ground validation and surface model based on SRTM DEM data corrected for deforestation

    Directory of Open Access Journals (Sweden)

    G. M. Moulatlet

    2014-07-01

    Full Text Available One of the most important freely available digital elevation models (DEMs for Amazonia is the one obtained by the Shuttle Radar Topography Mission (SRTM. However, since SRTM tends to represent the vegetation surface instead of the ground surface, the broad use of SRTM DEM as a framework for terrain description in Amazonia is hampered by the presence of deforested areas. We present here two datasets: (1 a deforestation-corrected SRTM DEM for the interfluve between the Purus and Madeira rivers, in central Amazonia, which passed through a careful identification of different environments and has deforestation features corrected by a new method of increasing pixel values of the DEM; and (2 a set of eighteen hydrological-topographic descriptors based on the corrected SRTM DEM. The hydrological-topographic description was generated by the Height Above the Nearest Drainage (HAND algorithm, which normalizes the terrain elevation (a.s.l. by the elevation of the nearest hydrologically connected drainage. The validation of the HAND dataset was done by in situ hydrological description of 110 km of walking trails also available in this dataset. The new SRTM DEM expands the applicability of SRTM data for landscape modelling; and the datasets of hydrological features based on topographic modelling is undoubtedly appropriate for ecological modelling and an important contribution for environmental mapping of Amazonia. The deforestation-corrected SRTM DEM is available at http://ppbio.inpa.gov.br/knb/metacat/naman.318.3/ppbio; the polygons selected for deforestation correction are available at http://ppbio.inpa.gov.br/knb/metacat/naman.317.3/ppbio; the set of hydrological-topographic descriptors is available at http://ppbio.inpa.gov.br/knb/metacat/naman.544.2/ppbio; and the environmental description of access trails is available at http://ppbio.inpa.gov.br/knb/metacat/naman.541.2/ppbio.

  2. A GIS-based Spatial Analysis of Volcanoes in the Central Andes: Insights Into Factors Controlling Volcano Spacing.

    Science.gov (United States)

    Savant, S. S.; de Silva, S. L.

    2005-12-01

    r°S). The central part of the arc between 22 r° and 24 r°S shows the highest density of volcanoes. An interpolated continuous raster grid of volcano base elevation revealed a strong positive correlation with the density of volcanoes. Interestingly, the spacing of the peaks in density is fairly regular at about 75 to 110 km. We interpret the different orders of spacing as reflecting control by different levels within the plumbing system for the arc. The spacing of density peaks (clusters) is likely the primary spacing of diapirs rising from the source layer into the lithosphere. The dominant 10 to 30 km spacing of individual volcanoes probably reflects the influence of intra-crustal regions superimposed on the primary spacing. These regions may be mid-crustal, low-velocity, high-conductivity zones that have been imaged geophysically and/or the influence of older upper crustal batholiths that may have been emplaced into the thickest crust between 22 r° and 24 r°S.

  3. Phylogenetic relationships between telmatobiinids (Anura, Ceratophryidae, Telmatobiinae) of central Andes based on morphology of larval and adult stages

    OpenAIRE

    César Aguilar; Niels Valencia

    2011-01-01

    Batrachophrynus and Telmatobius are the two genus of Telmatobiinae from the central Andes. Both genera have species with adaptations for life at high altitude in the Andes, with aquatic or semi-aquatic habits in creeks, lagoons and lakes. The objective of this study is to evaluate the phylogenetic relationships between Batrachophrynus and 13 species of Telmatobius from the central Andes using larval and adult morphology including diagnostic characters for Batrachophrynus and Telmatobius, and ...

  4. Neuroarchitecture and neuroanatomy of the Drosophila central complex: A GAL4-based dissection of protocerebral bridge neurons and circuits.

    Science.gov (United States)

    Wolff, Tanya; Iyer, Nirmala A; Rubin, Gerald M

    2015-05-01

    Insects exhibit an elaborate repertoire of behaviors in response to environmental stimuli. The central complex plays a key role in combining various modalities of sensory information with an insect's internal state and past experience to select appropriate responses. Progress has been made in understanding the broad spectrum of outputs from the central complex neuropils and circuits involved in numerous behaviors. Many resident neurons have also been identified. However, the specific roles of these intricate structures and the functional connections between them remain largely obscure. Significant gains rely on obtaining a comprehensive catalog of the neurons and associated GAL4 lines that arborize within these brain regions, and on mapping neuronal pathways connecting these structures. To this end, small populations of neurons in the Drosophila melanogaster central complex were stochastically labeled using the multicolor flip-out technique and a catalog was created of the neurons, their morphologies, trajectories, relative arrangements, and corresponding GAL4 lines. This report focuses on one structure of the central complex, the protocerebral bridge, and identifies just 17 morphologically distinct cell types that arborize in this structure. This work also provides new insights into the anatomical structure of the four components of the central complex and its accessory neuropils. Most strikingly, we found that the protocerebral bridge contains 18 glomeruli, not 16, as previously believed. Revised wiring diagrams that take into account this updated architectural design are presented. This updated map of the Drosophila central complex will facilitate a deeper behavioral and physiological dissection of this sophisticated set of structures. PMID:25380328

  5. Structure-based functional characterization of repressor of toxin (Rot), a central regulator of Staphylococcus aureus virulence.

    Science.gov (United States)

    Killikelly, April; Benson, Meredith A; Ohneck, Elizabeth A; Sampson, Jared M; Jakoncic, Jean; Spurrier, Brett; Torres, Victor J; Kong, Xiang-Peng

    2015-01-01

    Staphylococcus aureus is responsible for a large number of diverse infections worldwide. In order to support its pathogenic lifestyle, S. aureus has to regulate the expression of virulence factors in a coordinated fashion. One of the central regulators of the S. aureus virulence regulatory networks is the transcription factor repressor of toxin (Rot). Rot plays a key role in regulating S. aureus virulence through activation or repression of promoters that control expression of a large number of critical virulence factors. However, the mechanism by which Rot mediates gene regulation has remained elusive. Here, we have determined the crystal structure of Rot and used this information to probe the contribution made by specific residues to Rot function. Rot was found to form a dimer, with each monomer harboring a winged helix-turn-helix (WHTH) DNA-binding motif. Despite an overall acidic pI, the asymmetric electrostatic charge profile suggests that Rot can orient the WHTH domain to bind DNA. Structure-based site-directed mutagenesis studies demonstrated that R(91), at the tip of the wing, plays an important role in DNA binding, likely through interaction with the minor groove. We also found that Y(66), predicted to bind within the major groove, contributes to Rot interaction with target promoters. Evaluation of Rot binding to different activated and repressed promoters revealed that certain mutations on Rot exhibit promoter-specific effects, suggesting for the first time that Rot differentially interacts with target promoters. This work provides insight into a precise mechanism by which Rot controls virulence factor regulation in S. aureus.

  6. A Review of a Successful Unsubsidized Market-Based Rural Solar Development Initiative in Laikipia District, Central Kenya

    Directory of Open Access Journals (Sweden)

    O. Wambuguh

    2013-10-01

    Full Text Available The development of renewable energy technologies (RETs in many areas far from grid-based electricity have primarily involved solar photovoltaics (SPVs which tap solar radiation to provide heat, light, hot water, electricity, and cooling for homes, businesses, and industry. A study on RETs took place in the Wiyumiririe Location of Laikipia District (north-central Kenya, a rich agricultural region. To explore this solar initiative in such a remote part of the country, a purposive randomized convenience sample of 246 households was selected and landowner interviews conducted, followed by field visits and observations. Although more than half of the households visited had SPV installations, solar energy was found to contribute only 18% of household estimated total energy needs; most residents still primarily relying on traditional energy sources. Several types of solar panels of different capacities and costs were utilized. Many landowners had at least one or two rooms using solar energy for household lighting, for appliance charging and to power radio and television. Almost all respondents appreciated that solar energy was clean renewable energy that greatly improved household living conditions; gave them some prestige; was easy to use and maintain; and was available year around. Although such significant benefits were associated with SPVs, only about 40% of residents interviewed were somehow satisfied with its development. Respondents expressed specific developmental initiatives that were closely associated with the availability of solar energy. Nevertheless, a number of challenges were raised associated with SPVs primarily investment capital and equipment costs and maintenance. As solutions to capital building will not solely rely on subsidies or individual farmer inputs, strategies must be found to mobilize the essential and tested tools for success including sustainable capital generation, building local institutions and capacities that

  7. FLUID DYNAMICS PROCESSES AT THE CENTRAL SAKHALIN FAULT (BASED ON OBSERVATIONS OF THE YUZHNO-SAKHALINSK MUD VOLCANO

    Directory of Open Access Journals (Sweden)

    Valery V. Ershov

    2015-10-01

    Full Text Available The Yuzhno-Sakhalinsk mud volcano is located in the southern part of the Sakhalin Island within the area of the Central Sakhalin fault, one of the largest disjunctive dislocations of the island. The volcano was monitored during field seasons in the period from 2005 to 2007, and data on flow rates, chemical and isotope compositions of gases, temperature and chemical composition of watermud mixture in the volcano’s blowouts were collected and analysed. During the observation period, seismic activity in the region under study was significantly variable in time and space. The monitoring results revealed «traces» of two earthquakes in the blowout activity of the Yuzhno-Sakhalinsk mud volcano – the Gornazavodsk earthquake, that took place on 17 (18 August 2006, and the Nevelsk earthquake of 2 August 2007. Based on results of our analyses of the field data and mathematical simulation data, it is possible to conclude that an additional inflow of «deep geofluids» could not have been a major trigger of the activity of the volcano after the earthquakes. In our opinion, all the observed anomalies may result from «water – rock – gas» interactions in the top part of the mud volcano’s feeder channel. A combination of water and gas flows in the volcano’s channel and silica-alumina rocks comprises a specific geochemical system that is sensitive to external (seismic impacts. Therefore, comprehensive consideration of physical and chemical processes within fluid-dynamic systems is required for assurance of correct interpretation of empirical data.

  8. Field based measurements of albedo for two candidate perennial cellulosic feedstocks and row crops in Central Illinois

    Science.gov (United States)

    Miller, J. N.; VanLoocke, A.; Bernacchi, C. J.

    2012-12-01

    The production of perennial cellulosic feedstocks for bioenergy present the potential to diversify regional economies and the national energy supply, while also serving as a climate 'regulators' due to a number of biogeochemical and biophysical differences relative to row crops. Numerous observationally and modeling based approaches, including life cycle analyses have investigated biogeochemical tradeoffs, such as increased carbon sequestration and biophysical increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biophysical changes associated with the difference in albedo, which will alter the local energy balance and could cause a local to regional cooling several times larger than that associated with offsetting carbon. To address this factor an experiment consisting of paired fields of Miscanthus and Switchgrass, two of the leading perennial cellulosic feedstock candidates, and traditional row crops was established in central Illinois. Data from the first two growing seasons indicate that this effect is most pronounced during the spring and fall as perennial biofuel crops green up earlier and senesce later than common annual row crops. The albedo of the perennials converges to that of the row crops during the growing season as the canopies develop. During the early winter, before the perennial crops are harvested, the albedo over fallow soybean and maize fields can vary greatly depending on snowfall and, to a lesser extent, soil moisture, whereas perennials show less variation. Thus, perennial biofuel crops also have the potential to buffer the local environment against short-term variations in climate. These factors should be considered when evaluating the tradeoffs and climate-regulation services associated with large-scale planting of bioenergy crops.

  9. Central metabolic responses to the overproduction of fatty acids in Escherichia coli based on 13C-metabolic flux analysis.

    Science.gov (United States)

    He, Lian; Xiao, Yi; Gebreselassie, Nikodimos; Zhang, Fuzhong; Antoniewiez, Maciek R; Tang, Yinjie J; Peng, Lifeng

    2014-03-01

    We engineered a fatty acid overproducing Escherichia coli strain through overexpressing tesA (“pull”) and fadR (“push”) and knocking out fadE (“block”). This “pull-push-block” strategy yielded 0.17 g of fatty acids (C12–C18) per gram of glucose (equivalent to 48% of the maximum theoretical yield) in batch cultures during the exponential growth phase under aerobic conditions. Metabolic fluxes were determined for the engineered E. coli and its control strain using tracer ([1,2-13C]glucose) experiments and 13C-metabolic flux analysis. Cofactor (NADPH) and energy (ATP) balances were also investigated for both strains based on estimated fluxes. Compared to the control strain, fatty acid overproduction led to significant metabolic responses in the central metabolism: (1) Acetic acid secretion flux decreased 10-fold; (2) Pentose phosphate pathway and Entner–Doudoroff pathway fluxes increased 1.5- and 2.0-fold, respectively; (3) Biomass synthesis flux was reduced 1.9-fold; (4) Anaplerotic phosphoenolpyruvate carboxylation flux decreased 1.7-fold; (5) Transhydrogenation flux converting NADH to NADPH increased by 1.7-fold. Real-time quantitative RT-PCR analysis revealed the engineered strain increased the transcription levels of pntA (encoding the membrane-bound transhydrogenase) by 2.1-fold and udhA (encoding the soluble transhydrogenase) by 1.4-fold, which is in agreement with the increased transhydrogenation flux. Cofactor and energy balances analyses showed that the fatty acid overproducing E. coli consumed significantly higher cellular maintenance energy than the control strain. We discussed the strategies to future strain development and process improvements for fatty acid production in E. coli.

  10. One case of treatment of maxillar incisor defect by aesthetic multi-layering technique with composite%复合树脂多层色仿真美学修复上颌前牙1例

    Institute of Scientific and Technical Information of China (English)

    朱静

    2012-01-01

    Multi-layering aesthetic technique was applied to restore the defects of maxillar central incisors in one case. Simulate dentine and enamel of upper anterior teeth with 1 opaque dentine shade and 3 translucent enamel shades were used respectively to match the color of natural teeth. The natural aesthetic treatment was combined with the traditional composite resin and bonding technique. The effect of aesthetic multi-layering technique is better than that of common one layer restoration.%用复合树脂多层色仿真美学修复方法修复上颌前牙缺陷,分别使用美于自然树脂不透明牙本质色1种、半透明牙釉质色3种模拟上前牙牙本质层和牙釉质层的颜色,最大程度恢复患者缺陷牙的真实状态,配合传统树脂粘接修复技术,完成自然美学修复,优于普通单层色树脂修复.

  11. Variability of floods, droughts and windstorms over the past 500 years in Central Europe based on documentary and instrumental data

    Science.gov (United States)

    Brazdil, Rudolf

    2016-04-01

    Hydrological and meteorological extremes (HMEs) in Central Europe during the past 500 years can be reconstructed based on instrumental and documentary data. Documentary data about weather and related phenomena represent the basic source of information for historical climatology and hydrology, dealing with reconstruction of past climate and HMEs, their perception and impacts on human society. The paper presents the basic distribution of documentary data on (i) direct descriptions of HMEs and their proxies on the one hand and on (ii) individual and institutional data sources on the other. Several groups of documentary evidence such as narrative written records (annals, chronicles, memoirs), visual daily weather records, official and personal correspondence, special prints, financial and economic records (with particular attention to taxation data), newspapers, pictorial documentation, chronograms, epigraphic data, early instrumental observations, early scientific papers and communications are demonstrated with respect to extraction of information about HMEs, which concerns usually of their occurrence, severity, seasonality, meteorological causes, perception and human impacts. The paper further presents the analysis of 500-year variability of floods, droughts and windstorms on the base of series, created by combination of documentary and instrumental data. Results, advantages and drawbacks of such approach are documented on the examples from the Czech Lands. The analysis of floods concentrates on the River Vltava (Prague) and the River Elbe (Děčín) which show the highest frequency of floods occurring in the 19th century (mainly of winter synoptic type) and in the second half of the 16th century (summer synoptic type). Reported are also the most disastrous floods (August 1501, March and August 1598, February 1655, June 1675, February 1784, March 1845, February 1862, September 1890, August 2002) and the European context of floods in the severe winter 1783/84. Drought

  12. Effect of Direct Seeding Mulch-Based Systems on Soil Carbon Storage and Macrofauna in Central Brazil

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    Eric Blanchart

    2007-03-01

    Full Text Available Soils represent a large carbon pool, approximately 1500 Gt, equivalent to almost three times the quantity stored in terrestrial biomass and twice the amount stored in the atmosphere. Any modification of land-use or land management can induce variations in soil carbon stocks, even in agricultural systems that are perceived to be in a steady state. These modifications also alter soil macrofauna that is known to affect soil carbon dynamics. Direct seeding Mulch-based Cropping (DMC systems with two crops per year without soil tillage have widely been adopted over the last 10 to 15 years in the Cerrado (central region of Brazil. They are replacing the traditional soybean monocropping with fallow under conventional tillage (CT. The objective of this study was to examine how DMC practices affect soil organic carbon (SOC dynamics and macrofauna (Rio Verde, Goias State. The approach was to determine soil C stocks and macrofauna in five fields under DMC aged 1, 5, 7, 11 and 13 years. In order to compare DMC systems with the native system of the region and previous land-use, a situation under native Cerrado (tree-savanna like vegetation and a field conducted traditionally (CT were also studied. Soil C stocks were calculated for the 0-10 and 0-40 cm soil depth and also for the first 400 kg m-2 of soil to compare the same amount of soil and to suppress the potential artefact of soil compaction when sample is based on fix layer depth. Soil macrofauna was hand-sorted from soil monoliths (30 cm depth, TSBF method. In our study, the annual rate of carbon storage was equal to ca. 1.6 MgC ha-1, which is in the range of values measured for DMC in different areas of Brazil, i.e., 0.4 to 1.7 MgC ha-1 with the highest rates obtained in the Cerrado region. Compared to natural vegetation, soil macrofauna in cropped systems was strongly modified. In CT, biomass and density were very low and much lower than in DMC systems. With increasing age of DMC, total macrofauna

  13. GIS-based landslide susceptibility mapping models applied to natural and urban planning in Trikala, Central Greece

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    Skilodimou, H. D.

    2009-06-01

    Full Text Available Landslide susceptibility mapping is a practical tool in natural and urban planning; it can be applied for determining land use zones, in construction design and planning of a variety of projects. In this study, two different GIS based landslide susceptibility maps were generated in the mountainous part of the Trikala Prefecture in Thessaly, Central Greece. This was accomplished by using different methods for correlating factors, which have an effect on landslide occurrences. The instability factors taken into account were: lithology, tectonic features, slope gradients, road network, drainage network, land use and rainfall. A frequency distribution of the half number of the landslide events of the study area in each class of the instability factors was performed in order to rate the classes. Two models have been used to combine the instability factors and assess the overall landslide susceptibility, namely: the Weight Factor Model (WeF, which is a statistical method, and the Multiple Factor Model (MuF that is a logical method. The produced maps were classified into four zones: Low, Moderate, High and Very High susceptible zones and validated using the other half number of the landslide events of the area. Evaluation of the results is optimized through a Landslide Models Indicator (La.M.I..Los mapas de susceptibilidad de deslizamientos representan una práctica herramienta en la planificación urbana y de espacios naturales. Así, puede aplicarse a la determinación de los usos de terrenos, en el diseño de construcción civil y para la planificación de gran variedad de actividades. En este estudio se generaron dos tipos diferentes de mapas de susceptibilidad basados en GIS para la parte montañosa de la prefectura de Trikala en Tesalia (Grecia Central. Estos se llevaron a cabo usando dos métodos de correlación de los factores que pueden tener un efecto en la generación de deslizamientos. Los factores de desestabilización tenidos en cuenta

  14. 下切牙先天缺失错(牙合)畸形的临床治疗%Treatment for malocclusions with congenital missing lower incisors

    Institute of Scientific and Technical Information of China (English)

    袁代润; 钱红; 闫英剑

    2011-01-01

    Objective To investigate the treatment strategies for malocclusions with congenital missing lower incisors Methods 22 patients who had malocclusions with congenital missing lower incisors were selected.The position and number of congenital missing lower incisors,classification of malocclusions and treatment strategies were studied.Results In 10 patients with one congenital missing lower incisor,5 had tooth extraction, 3 had interproximal enamel stripping and 2 had combined orthodontic and prosthetic treatment.In 12 patients with two congenital missing lower incisors,8 had tooth extraction and 4 had combined orthodontic and prosthetic treatment.After treatment,all patients acquired normal occlusion and the Bolton index was coordinated in the upper and lower dentitions.Conclusion In malocclusions with congenital missing lower incisors,different treatment strategies should be made according to patient's age,facial type,protrusion of incisors,midline,absent incisor position and number, and manifestation of malocclusions,in order to acquire good occlusion and esthetics.%目的:探讨下切牙先天缺失错(牙合)畸形的临床治疗方法.方法:选择下切牙先天缺失的错(牙合)畸形患者22例,对缺牙部位、缺牙数目、错(牙合)类型、矫治方法等进行分析.结果:10例单颗下切牙先天缺失患者中,有5例采用减数矫治,2例采用减径矫治,3例采用正畸结合修复的方法进行治疗.12例两颗下切牙先天缺失患者中,有8例采用减数矫治,4例采用正畸结合修复的方法进行治疗.治疗后所有患者上下牙列Bolton指数协调,咬合关系达到正常,侧貌外形得到改善.结论:对于下切牙先天缺失的错(牙合)畸形,应该根据患者的年龄、面型、牙弓突度、下切牙缺失部位、数目、中线及错(牙合)畸形等情况,在Bolton指数的指导下,制定不同的治疗计划,以达到良好的咬合关系和美观效果.

  15. Evaluation of the position of lower incisors in the mandibular symphysis of individuals with Class II malocclusion and Pattern II profiles

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    Djalma Roque Woitchunas

    2012-06-01

    Full Text Available OBJECTIVES: This study evaluated the position of mandibular incisors in the mandibular symphysis of individuals with Class II malocclusion and Pattern II profiles. METHODS: The sample consisted of 40 Caucasian patients (20 male and 20 female with Class II malocclusion and Pattern II profile from 10 to 18 years of age (mean age of 12.84 years who were selected from the records of the School of Dentistry of Universidade de Passo Fundo, Brazil. The linear cephalometric measurements used in this study were Ricketts' 1- AP, Interlandi's line I and Vigorito's 1-VT; and the angular measurement studied was the mandibular plane angle (IMPA. RESULTS: Mandibular incisors of individuals with Class II malocclusion and Pattern II profile tended to be buccally inclined and protruded.

  16. Organizational centralization in radiology.

    Science.gov (United States)

    Aas, I H Monrad

    2006-01-01

    Traditionally, hospitals have a radiology department, where images are taken and interpretation occurs. Teleradiology makes it possible to capture images in one location and transmit them elsewhere for interpretation. Organizational centralization of radiology interpretations is therefore of interest. Empirical data have been collected in qualitative interviews of 26 resource persons with substantial experience with picture archiving and communication systems and teleradiology, from 12 departments of radiology in Norway. The response rate was 90%. A total of 21 theoretically possible types of centralization of image interpretation were identified, representing combinations of three categories of geographical centralization, and seven categories of centralization according to function. Various advantages and disadvantages of centralization were identified. Organizational changes may be decisive for the future of teleradiology, but it may be wise to plan for change in small steps, since we know little about how broad future organizational changes based on teleradiology will be, or what will decide how far particular organizations will go. PMID:16438776

  17. Management of a Congenitally Missing Lateral Incisor with Orthodontics, Bone Grafting (a New Method and Single-Tooth Implant: A Case Report

    Directory of Open Access Journals (Sweden)

    Hamid Reza Arab

    2014-03-01

    Full Text Available Careful treatment planning, space management, augmentation of bone and attention to the details of implant surgical and prosthetic techniques are important factors when treating anterior maxilla specially replacement of missing teeth. This case report addresses a chair-side ridge augmentation procedure using autograft bone harvested with trephine drills and placed without using screws and the fundamental considerations related to replacement of a congenitally missing lateral incisor by a team approach

  18. Spatial Analysis of the Central Place System Based on Accessibility%基于可达性的中心地体系的空间分析

    Institute of Scientific and Technical Information of China (English)

    张莉; 陆玉麒

    2013-01-01

    以克里斯泰勒的中心地理论为基础,以最短通行时间、加权平均出行时间作为可达性的评价指标,以基于GIS平台开发的可达性计算模块为技术支撑,从空间可达性、空间相互作用、空间服务范围几个方面对均质背景和交通背景下的中心地体系进彳空间分析,探讨中心地体系的空间演化及空间重构,以期对中心地体系的过程模拟和空间表达进行初步探索性的尝试.结果表明:均质背景下,次一级中心地产生于上一级中心地可达时间最长的地方;基于加权平均出行时间的可达性在同等级的中心地间出现了差异,相同等级的中心地越是靠近高等级中心地,其加权平均出行时间越短,由于中心地相对区位的不同,同一等级的中心地之间出现了差异增长,其结果会形成连续的中心地等级.伴随着交通网络的演进,中心地空间结构进入由“点-轴-网”构成的全面有组织的均衡发展阶段.%Based on the central place theory proposed by Walter Christaller,taking the shortest time and weighted average travel time as the accessibility evaluation index,using the accessibility calculation module as technical support based on the GIS platform,the spatial evolution and reconstruction of the central place system are explored from the aspects of spatial accessibility,spatial interactions,spatial scope of services under homogeneous background and transportation background.Through this way,formation process simulation and spatial expression of central place system are probed preliminary.The result shows that:Firstly,the secondary central place appears in the area which accessibility time is longest to the superior center under homogeneous background.Under the assumption of homogeneous plain,traffic in any direction are the same.The central place appears in the center of the hexagonal market area which accessibility is best and then present the concentric circles diffusion

  19. Adapting to climate variability and change: experiences from cereal-based farming in the central rift and Kobo Valleys, Ethiopia.

    Science.gov (United States)

    Kassie, Belay Tseganeh; Hengsdijk, Huib; Rötter, Reimund; Kahiluoto, Helena; Asseng, Senthold; Van Ittersum, Martin

    2013-11-01

    Small-holder farmers in Ethiopia are facing several climate related hazards, in particular highly variable rainfall with severe droughts which can have devastating effects on their livelihoods. Projected changes in climate are expected to aggravate the existing challenges. This study examines farmer perceptions on current climate variability and long-term changes, current adaptive strategies, and potential barriers for successful further adaptation in two case study regions-the Central Rift Valley (CRV) and Kobo Valley. The study was based on a household questionnaire, interviews with key stakeholders, and focus group discussions. The result revealed that about 99 % of the respondents at the CRV and 96 % at the Kobo Valley perceived an increase in temperature and 94 % at CRV and 91 % at the Kobo Valley perceived a decrease in rainfall over the last 20-30 years. Inter-annual and intraseasonal rainfall variability also has increased according to the farmers. The observed climate data (1977-2009) also showed an increasing trend in temperature and high inter-annual and intra-seasonal rainfall variability. In contrast to farmers' perceptions of a decrease in rainfall totals, observed rainfall data showed no statistically significant decline. The interaction among various bio-physical and socio-economic factors, changes in rainfall intensity and reduced water available to crops due to increased hot spells, may have influenced the perception of farmers with respect to rainfall trends. In recent decades, farmers in both the CRV and Kobo have changed farming practices to adapt to perceived climate change and variability, for example, through crop and variety choice, adjustment of cropping calendar, and in situ moisture conservation. These relatively low-cost changes in farm practices were within the limited adaptation capacity of farmers, which may be insufficient to deal with the impacts of future climate change. Anticipated climate change is expected to impose new

  20. Adapting to Climate Variability and Change: Experiences from Cereal-Based Farming in the Central Rift and Kobo Valleys, Ethiopia

    Science.gov (United States)

    Kassie, Belay Tseganeh; Hengsdijk, Huib; Rötter, Reimund; Kahiluoto, Helena; Asseng, Senthold; Van Ittersum, Martin

    2013-11-01

    Small-holder farmers in Ethiopia are facing several climate related hazards, in particular highly variable rainfall with severe droughts which can have devastating effects on their livelihoods. Projected changes in climate are expected to aggravate the existing challenges. This study examines farmer perceptions on current climate variability and long-term changes, current adaptive strategies, and potential barriers for successful further adaptation in two case study regions—the Central Rift Valley (CRV) and Kobo Valley. The study was based on a household questionnaire, interviews with key stakeholders, and focus group discussions. The result revealed that about 99 % of the respondents at the CRV and 96 % at the Kobo Valley perceived an increase in temperature and 94 % at CRV and 91 % at the Kobo Valley perceived a decrease in rainfall over the last 20-30 years. Inter-annual and intraseasonal rainfall variability also has increased according to the farmers. The observed climate data (1977-2009) also showed an increasing trend in temperature and high inter-annual and intra-seasonal rainfall variability. In contrast to farmers’ perceptions of a decrease in rainfall totals, observed rainfall data showed no statistically significant decline. The interaction among various bio-physical and socio-economic factors, changes in rainfall intensity and reduced water available to crops due to increased hot spells, may have influenced the perception of farmers with respect to rainfall trends. In recent decades, farmers in both the CRV and Kobo have changed farming practices to adapt to perceived climate change and variability, for example, through crop and variety choice, adjustment of cropping calendar, and in situ moisture conservation. These relatively low-cost changes in farm practices were within the limited adaptation capacity of farmers, which may be insufficient to deal with the impacts of future climate change. Anticipated climate change is expected to impose new