Influence of shovel-shaped incisors on the dental arch crowding in Mongolian females.

Science.gov (United States)

Hasegawa, Yuh; Terada, Kazuto; Kageyama, Ikuo; Tsukada, Shin-ichi; Uzuka, Satoshi; Nakahara, Rizako; Nakahara, Sen

2009-08-01

The aim of this study was to investigate the influences of shovel-shaped incisors on the dental arch crowding in the samples of modern young female adult Mongolians (belonging to the Khalkha-Mogol grouping) ranged between 18.5 and 25.0 years, with a mean age of 20.7 years. Materials in this study comprised of 33 dental casts. Plaster replicas of the A.S.U. system plaques were used to facilitate standardization in scoring and classify shoveling regarding both upper central and lateral incisors. Dimensions of the dental arch namely, overjet, overbite, arch depth, arch width and irregularity index were measured. The correlation between the shovel shape of the central incisor and the lateral incisor was highly significant. Significantly relations were found between the grades of shoveling and the mesiodistal diameters of upper first molars and lower incisors. Positive correlation was admitted between the shoveling and upper arch depth anterior, and upper arch depth. It may be considered that the grades of shoveling are indirectly related with upper and/or lower anterior crowding. Although crowding is looks like an expression of disharmony between teeth and alveolar arch, it may be caused by multiple etiologic factors interacted directly and/or indirectly.

Masticatory Efficiency of Shortened Dental Arch Subjects with ...

African Journals Online (AJOL)

2017-05-16

May 16, 2017 ... of shortened dental arch subjects with removable partial denture: A comparative ... at the post- and pre-treatment phases was statistically significant (P = 0.001). The .... after the delivery of metal-based RPD with the denture in.

Dental arch changes associated with rapid maxillary expansion: A retrospective model analysis study

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Ivor M D′Souza

2015-01-01

Full Text Available Introduction: Transverse deficiency of the maxilla is a common clinical problem in orthodontics and dentofacial orthopedics. Transverse maxillary deficiency, isolated or associated with other dentofacial deformities, results in esthetic and functional impairment giving rise to several clinical manifestations such as asymmetrical facial growth, positional and functional mandibular deviations, altered dentofacial esthetics, adverse periodontal responses, unstable dental tipping, and other functional problems. Orthopedic maxillary expansion is the preferred treatment approach to increase the maxillary transverse dimension in young patients by splitting of the mid palatal suture. This orthopedic procedure has lately been subject of renewed interest in orthodontic treatment mechanics because of its potential for increasing arch perimeter to alleviate crowding in the maxillary arch without adversely affecting facial profile. Hence, the present investigation was conducted to establish a correlation between transverse expansion and changes in the arch perimeter, arch width and arch length. Methods: For this purpose, 10 subjects (five males, five females were selected who had been treated by rapid maxillary expansion (RME using hyrax rapid palatal expander followed by fixed mechanotherapy (PEA. Pretreatment (T1, postexpansion (T2, and posttreatment (T3 dental models were compared for dental changes brought about by RME treatment and its stability at the end of fixed mechanotherapy. After model measurements were made, the changes between T1-T2, T2-T3 and T1-T3 were determined for each patient. The mean difference between T1-T2, T2-T3 and T1-T3 were compared to assess the effects of RME on dental arch measurements. Results are expressed as mean ± standard deviation and are compared by repeated measures analysis of variance followed by a post-hoc test. Arch perimeter changes are correlated with changes in arch widths at the canine, premolar and molar

Decayed/missing/filled teeth and shortened dental arches in Tanzanian adults.

NARCIS (Netherlands)

Sarita, P.T.N.; Witter, D.J.; Kreulen, C.M.; Matee, M.I.N.; Hof, M.A. van 't; Creugers, N.H.J.

2004-01-01

PURPOSE: This study assessed decayed/missing/filled teeth (DMFT), presence of occlusal units, and prevalence of shortened dental arches in a Tanzanian adult population. MATERIALS AND METHODS: The dental state of samples of the Tanzanian population was studied. Oral examinations were conducted on

Masticatory efficiency of shortened dental arch subjects with ...

African Journals Online (AJOL)

Objective: The objective of this study was to compare the masticatory efficiency in subjects with shortened dental arch (SDA) before and after restoration with removable partial denture (RPD). Materials and Methods: This was a prospective study carried out on 36 consecutive patients. The subjects were asked to chew 5 g of ...

Three-dimensional dental arch changes of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusion

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Adriano Porto Peixoto

2014-08-01

Full Text Available INTRODUCTION: This study assessed the three-dimensional changes in the dental arch of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusions at three different periods. METHODS: Landmarks previously identified on upper and lower dental casts were digitized on a three-dimensional digitizer MicroScribe-3DX and stored in Excel worksheets in order to assess the width, length and depth of patient's dental arches. RESULTS: During orthodontic preparation, the maxillary and mandibular transverse dimensions measured at the premolar regions were increased and maintained throughout the follow-up period. Intercanine width was increased only in the upper arch during orthodontic preparation. Maxillary arch length was reduced during orthodontic finalization, only. Upper and lower arch depths were stable in the study periods. Differences between centroid and gingival changes suggested that upper and lower arch premolars buccaly proclined during the pre-surgical period. CONCLUSIONS: Maxillary and mandibular dental arches presented transverse expansion at premolar regions during preoperative orthodontic preparation, with a tendency towards buccal tipping. The transverse dimensions were not altered after surgery. No sagittal or vertical changes were observed during the follow-up periods.

Three-dimensional dental arch changes of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusion.

Science.gov (United States)

Peixoto, Adriano Porto; dos Santos Pinto, Ary; Garib, Daniela Gamba; Gonçalves, João Roberto

2014-01-01

This study assessed the three-dimensional changes in the dental arch of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusions at three different periods. Landmarks previously identified on upper and lower dental casts were digitized on a three-dimensional digitizer MicroScribe-3DX and stored in Excel worksheets in order to assess the width, length and depth of patient's dental arches. During orthodontic preparation, the maxillary and mandibular transverse dimensions measured at the premolar regions were increased and maintained throughout the follow-up period. Intercanine width was increased only in the upper arch during orthodontic preparation. Maxillary arch length was reduced during orthodontic finalization, only. Upper and lower arch depths were stable in the study periods. Differences between changes in centroid and gingival points suggested that upper and lower premolars buccaly proclined during the pre-surgical period. Maxillary and mandibular dental arches presented transverse expansion at premolar regions during preoperative orthodontic preparation, with a tendency towards buccal tipping. The transverse dimensions were not altered after surgery. No sagittal or vertical changes were observed during the follow-up periods.

Alignment Strategy for Constricted Maxillary Dental Arch in Patients With Unilateral Cleft Lip and Palate Using Fixed Orthodontic Appliance.

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Park, Yoon-Hee; Park, Sumin; Baek, Seung-Hak

2018-03-01

The purpose of this study was to compare the alignment pattern of the constricted maxillary dental arch by fixed orthodontic treatment (FOT) in the well-aligned and constricted arches of unilateral cleft lip and palate (UCLP) patients. 19 UCLP patients were divided into Group 1 (well-aligned arch, n = 9) and Group 2 (constricted arch, n = 10). After the cephalometric and maxillary dental arch variables before (T1) and after FOT (T2) were measured, statistical analysis was performed. There were no significant differences in the surgical timing of cheiloplasty, palatoplasty, and secondary alveolar bone grafting and in the surgical method of cheiloplasty between the 2 groups. However, Group 2 had a higher percentage of palatoplasty method, which could leave the denuded bone for secondary healing than Group 1 (P dental arch compared to Group 1 at the T1 stage (inter-second premolar width, greater segment angle [GSA], and lesser segment angle [LSA], all P dental arch shape, different strategy is necessary to obtain proper alignment by FOT.

[Dysfunctional pathology from "true" and "de facto" mutilation of the dental arches].

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Garino, G B; Capurso, U

1989-01-01

The mutilations of the dental arches for agenesia, extractions or trauma and because of ankylosis, caries can be the cause of the disorders of the stomatognatic system. These problems are in relation with the time of the disfunction, the skeletal type and the interarches relationship. The pathogenetic factors are secondary to the amount and the direction of the dislocations or the entrapment of the lower jaw. The treatment planning can provide the closure of the spaces or the reopening. These procedures are demonstrated by two treated cases with TMJ disorders.

Knowledge and attitudes of dentists toward shortened dental arch ...

African Journals Online (AJOL)

Objective: The aim of this study was to assess and compare the knowledge and attitudes of dentists toward shortened dental arch (SDA) therapy in Saudi Arabia. Materials and Methods: In this cross‑sectional study, self‑designed‑structured questionnaires were distributed among specialists (SP), residents (RES), and ...

Tooth angulation and dental arch perimeter-the effect of orthodontic bracket prescription.

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Pontes, Luana F; Cecim, Rodolpho L; Machado, Sissy M; Normando, David

2015-08-01

The aim of this study was to evaluate the effects of upper incisors and canine angulations introduced by different bracket prescriptions on dental arch perimeter. Cone beam computerized tomography scans collected using I-Cat (Imaging Sciences International, Hatfield, PA, USA) were selected conveniently from a database of routine exams of a clinical radiology center. Crown and radicular measurements of upper incisors and canines were made and exported to the Autocad 2011 software to create a virtual dental model. The virtual teeth were positioned with an angulation of zero; thereafter, a reference value for the perimeter of the arch was measured. Furthermore, teeth angulations were applied according to the standards of the Edgewise bracket system and the Straight-wire systems: MBT, Capelozza, Andrews, and Roth. The largest linear distances for tooth crown (anterior arch perimeter) and root (radicular distance) were obtained for each bracket prescription. The anterior perimeter for well-aligned incisors and canines without angulation was used as reference (crown: 47.34mm; root: 39.13mm). An increase in the arch perimeter was obtained for all bracket prescriptions evaluated, which ranged from 0.28 and 3.19mm in the Edgewise technique, for the crown and root measurements, respectively, to 1.09 and 11.28mm for the Roth prescription. Bracket prescriptions with greater angulation led to an increased use of space within the dental arch, mainly in the radicular region. The consequence of this radicular angular displacement will need to be further investigated. © The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Intraoral 3D Scanning or Dental Impressions for the Assessment of Dental Arch Relationships in Cleft Care: Which is Superior?

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Chalmers, E V; McIntyre, G T; Wang, W; Gillgrass, T; Martin, C B; Mossey, P A

2016-09-01

This study was undertaken to evaluate intraoral 3D scans for assessing dental arch relationships and obtain patient/parent perceptions of impressions and intraoral 3D scanning. Forty-three subjects with nonsyndromic unilateral cleft lip and palate (UCLP) had impressions taken for plaster models. These and the teeth were scanned using the R700 Orthodontic Study Model Scanner and Trios® Digital Impressions Scanner (3Shape A/S, Copenhagen, Denmark) to create indirect and direct digital models. All model formats were scored by three observers on two occasions using the GOSLON and modified Huddart Bodenham (MHB) indices. Participants and parents scored their perceptions of impressions and scanning from 1 (very good) to 5 (very bad). Intra- and interexaminer reliability were tested using GOSLON and MHB data (Cronbach's Alpha >0.9). Bland and Altman plots were created for MHB data, with each model medium (one-sample t tests, P 0.9) were good for all formats with the direct digital models having the lowest interexaminer differences. Participants had higher ratings for scanning comfort (84.8%) than impressions (44.2%) (P impressions (51.2%) (P > .05). None disliked scanning, but 16.3% disliked impressions. Data for parents and children positively correlated (P 3D scans was superior to indirect digital and to plaster models; Subjects with UCLP preferred intra-oral 3D scanning to dental impressions, mirrored by parents/carers; This study supports the replacement of conventional impressions with intra-oral 3D scans in longitudinal evaluations of the outcomes of cleft care.

Three-dimensional dental arch changes of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusion

OpenAIRE

Peixoto,Adriano Porto; Pinto,Ary dos Santos; Garib,Daniela Gamba; Gonçalves,João Roberto

2014-01-01

INTRODUCTION: This study assessed the three-dimensional changes in the dental arch of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusions at three different periods. METHODS: Landmarks previously identified on upper and lower dental casts were digitized on a three-dimensional digitizer MicroScribe-3DX and stored in Excel worksheets in order to assess the width, length and depth of patient's dental arches. RESULTS: During orthodontic preparation, the m...

Effects of Asthma and Inhalation corticosteroids on the dental arch morphology in children

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S S Kumar

2012-01-01

Full Text Available Background: Hereditary, environmental and developmental factors play an important role in dentofacial development, as well as the initiation of malocclusion disorder. Allergic phenomenon such as asthma that induces an alternative mode of breathing in patients is a contributing factor in development of the dental arch. Aim: Our aim in this study was to evaluate the dentoalveolar morphology in asthmatic children and to analyze the effects of asthmatic medications on the dental arch. Setting and Design : This study is centered on 44 asthmatic children aged between 6-12 years from J.S.S Hospital, Mysore. Selected variables from model analysis of the casts of the asthmatic group were subjected to comparison with those of the non-asthmatic group, which comprised of 44 non-asthmatic children. Selected parameters were arch width, arch length and palatal depth. Materials and Methods : Impressions of upper and lower arches were made with rubber based impression material. A sliding digital caliper was used to measure the casts for arch width and arch length. A palatal depth gauge was used to measure the palatal depth. Statistical Analysis : Differences in arch widths, arch lengths and palatal depths between asthmatics and non-asthmatics groups were evaluated by independent sample t-tests. Chi-square test was applied to assess the frequency of occurrence of malocclusion in the asthmatic children. Result: The results obtained revealed that the arch length and palatal depth of asthmatic group had higher values compared to that of non-asthmatic groups for both age groups (6 to 8-year-old males and females, 10 to 12-year-old males and females. Inter molar width showed a significant lower value in asthmatics in the maxillary arches of 10 to 12-year-old females. Fifty percent of the asthmatic children aged 10 to 12-years had open-bite. Children under regular medication showed significant deviation in the dentoalveolar morphology as compared to those under

Speech evaluation and dental arch shape following pushback palatoplasty in cleft palate patients: Supraperiosteal flap technique versus mucoperiosteal flap technique.

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Ito, Shizuyo; Noguchi, Makoto; Suda, Yoshiyuki; Yamaguchi, Akira; Kohama, Geniku; Yamamoto, Etsuhide

2006-04-01

The aim of this study was to evaluate and compare the maxillary dental arch shape and speech of cleft palate patients following pushback palatoplasty using either the supraperiosteal flap technique or the mucoperiosteal flap technique. Sixty-two patients (29, cleft palate only; 33, unilateral cleft lip, alveolus and palate) operated on by the supraperiosteal technique and 47 patients (23, cleft palate only; 24 unilateral cleft lip, alveolus and palate) by the mucoperiosteal technique were reviewed in this study. Dental arch shape and speech proficiency at preschool and school age were evaluated in all patients. Dental arch shapes were classified as U type (good dental arch shape) and V type (narrow dental arch shape). In cleft palate only patients, U type was observed in 90% of the supraperiosteal group and 83% of the mucoperiosteal group. In unilateral cleft lip, alveolus and palate patients, U type was observed in 85% of the supraperiosteal group, while only in 33% of the mucoperiosteal group. In cleft palate only patients, normal speech at school age was observed 100% of the supraperiosteal group and 83% of the mucoperiosteal group. In unilateral cleft lip, alveolus and palate patients, normal speech at school age was observed in 97% of the supraperiosteal group and 75% of the mucoperiosteal group. Misarticulation was frequently found in patients with the V type of dental arch shape. It is suggested that pushback palatoplasty using the supraperiosteal technique is more advantageous for speech development compared with the mucoperiosteal technique.

Sleepiness, occlusion, dental arch and palatal dimensions in children attention deficit hyperactivity disorder (ADHD).

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Andersson, H; Sonnesen, L

2018-04-01

This was to compare sleepiness, occlusion, dental arch and palatal dimensions between children with attention deficit hyperactivity disorders (ADHD) and healthy children (control group). 15 children with ADHD (10 boys, 5 girls, mean age 10.98 years) and 36 healthy age matched children (21 boys, 15 girls, mean age 10.60 years) were included. Intra-oral three-dimensional scans of the teeth and palate were performed to evaluate the occlusion, dental arch and palatal dimensions. Sleepiness was evaluated from the questionnaires. The differences between the two groups were analysed by Fisher's exact test and general linear models adjusted for age and gender. The ADHD children had a significantly narrower dental arch at the gingival level of the canines (p ADHD children snored significantly more (p ADHD children had a tendency to sleep fewer hours during the night (p = 0.066) and felt inadequately rested in the morning (p = 0.051) compared to the controls. The results indicate that sleepiness and palatal width, especially the more anterior skeletal part of the palate, may be affected in children with ADHD. The results may prove valuable in the diagnosis and treatment planning of children with ADHD. Further studies are needed to investigate sleep and dental relations in children with ADHD.

Human evaluation in association to the mathematical analysis of arch forms: Two-dimensional study.

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Zabidin, Nurwahidah; Mohamed, Alizae Marny; Zaharim, Azami; Marizan Nor, Murshida; Rosli, Tanti Irawati

2018-03-01

To evaluate the relationship between human evaluation of the dental-arch form, to complete a mathematical analysis via two different methods in quantifying the arch form, and to establish agreement with the fourth-order polynomial equation. This study included 64 sets of digitised maxilla and mandible dental casts obtained from a sample of dental arch with normal occlusion. For human evaluation, a convenient sample of orthodontic practitioners ranked the photo images of dental cast from the most tapered to the less tapered (square). In the mathematical analysis, dental arches were interpolated using the fourth-order polynomial equation with millimetric acetate paper and AutoCAD software. Finally, the relations between human evaluation and mathematical objective analyses were evaluated. Human evaluations were found to be generally in agreement, but only at the extremes of tapered and square arch forms; this indicated general human error and observer bias. The two methods used to plot the arch form were comparable. The use of fourth-order polynomial equation may be facilitative in obtaining a smooth curve, which can produce a template for individual arch that represents all potential tooth positions for the dental arch. Copyright © 2018 CEO. Published by Elsevier Masson SAS. All rights reserved.

Treatment planning for patients with dental arch asymmetry caused by loss of a premolar on one side of the mouth

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Ivanova О.P.

2013-09-01

Full Text Available The objective of this study is to determine a selection criterion that is applicable for the treatment of patients with dental arch asymmetry caused by loss of a premolar on one side of the mouth. Material and methods. Fifty-seven patients (first maturity level who had some teeth extracted for orthodontic treatment were included in the study. The patients were divided into basic and control groups. We proposed to shape the extraction socket immediately after the extraction of a permanent tooth. In the basic group the extraction sockets were filled with osteoplastic material. Patients in the control group refused any surgical interventions. Results. According to a given criterion, the correlation between tooth size and dental arch parameters has been determined. When applying this criterion for finding the correlation, the frontal distal diagonal size of the dental arch was multiplied by 1.14 coefficient. The sum of the mesiodistal diameters of seven teeth in the half-arc was subtracted from the obtained value. The value which was equal to 0±1.0mm indicated the correlation between tooth size and dental arch parameters. Conclusion. If there is a correlation between tooth size and dental arch parameters, it is advisable to provide treatment associated with having the post-extraction socket opened and implant therapy performed (most commonly with the use of intraosseous dental implants.

Effect of dental arch convexity and type of archwire on frictional forces

NARCIS (Netherlands)

Fourie, Zacharias; Ozcan, Mutlu; Sandham, John

Introduction: Friction measurements in orthodontics are often derived from models by using brackets placed on flat models with various straight wires. Dental arches are convex in some areas. The objectives of this study were to compare the frictional forces generated in conventional flat and convex

Anchorage onto deciduous teeth: effectiveness of early rapid maxillary expansion in increasing dental arch dimension and improving anterior crowding.

Science.gov (United States)

Mutinelli, Sabrina; Manfredi, Mario; Guiducci, Antonio; Denotti, Gloria; Cozzani, Mauro

2015-01-01

Anchorage onto permanent dentition is a common procedure in rapid maxillary expansion. However, replacing first permanent molars with the second deciduous molars seems to be an option to reduce some negative side effects during orthodontic treatment. The purpose of this study was to evaluate the dental effect of rapid maxillary expansion with anchorage exclusively onto deciduous teeth performed in the first period of transition. Twenty patients with a lateral cross-bite treated exclusively by a Haas expander in early mixed dentition were retrospectively analyzed before treatment, at appliance removal, and at 21 months out of retention. The sagittal and transverse dimensions, together with the inter-canine arch and irregularity index, were digitally measured on scanned images of dental casts. The patients were compared with three balanced control groups (in total, 60 individuals) matched for gender. Two control groups had the same canine dental class as the treated group at T1, were in the inter-transitional period, and either had or lacked a lateral cross-bite. The last control group was comprised of adolescents in permanent dentition with a dental class I. The statistical analysis was performed by means of repeated-measures ANOVA for paired data and one-way ANOVA, the Kruskal-Wallis test, and the Mann-Whitney test for independent measures (α-level p dentition), the dental arch dimensions of treated patients were similar to those of adolescents with a dental class I and significantly wider than those of patients with a lateral cross-bite. Also, the anterior irregularity index was lower among patients who had undergone expansion treatments than in all untreated study participants. The Haas expander anchored to the deciduous teeth is effective in increasing the dental arch width in patients with a lateral cross-bite. The dimensions of the dental arch were modified earlier toward the values of the permanent dentition.

Morphological and Dimensional Characteristics of Dental Arch among Tribal and Non-tribal Population of Central India: A Comparative Study

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Yadav, Naveen S; Saxena, Vrinda; Vyas, Rajesh; Sharma, Rohit; Sharva, Vijayta; Dwivedi, Ashish; Jain, Manish

2014-01-01

Background: Differences in the dental arch among Bhil Aboriginals were investigated and compared with non-tribal individuals residing in a tribal zone of Central India. Plaster models (120) were made with the help of alginate impression of tribal adults as well as non-tribal adults residing in the same area. The supposition as aboriginals being primitive due to dietary practices maxillary arch size and mandibular arch size is distended in comparison to the non-tribal population as adaptation of soft refined diet has disrupted the growth of the jaws. Hence, an attempt was made to evaluate the arch widths of tribal population and to associate it with non-tribe population in the same area of Central India. Materials and Methods: Difference in morphology and dimension of the maxillary and mandibular arches was aimed at Bhil tribes as well as non-tribal residents of tribe rich zone of Central India. The study was steered amid 120 individuals both tribal and non-tribe equally around 60 each through a well-organized out-reach program intermittently. Study models were made of dental arches of all participants. All measurements of the arch dimension were patent on the study casts using an electronic digital sliding caliper. Pair t-test was applied by using SPSS software version-19.0. Results: In the maxillary arch, on appraisal the non-tribal and Bhil tribe’s subjects, it showed a statistically significant difference in inter-incisor width (2.95 mm), inter-canine width (2.60 mm), arch depth (3.25 mm). While inter premolar width (0.20 mm) and inter molar width (0.80 mm) anterior arch length (0.60 mm), and posterior arch length (0.10 mm) showed statistically not significant difference between non-tribal population and Bhil tribe subjects. In the mandibular arch, it showed a statistically significant difference in inter-canine width (1.00 mm). Although, inter-incisor width (0.72 mm), inter-molar width (0.80 mm), arch depth (0.90 mm), anterior arch length (0.30 mm), posterior

An Evaluation of Mandibular Dental and Basal Arch Dimensions in Class I and Class II Division 1 Adult Syrian Patients using Cone-beam Computed Tomography.

Science.gov (United States)

Al-Hilal, Layal H; Sultan, Kinda; Hajeer, Mohammad Y; Mahmoud, Ghiath; Wanli, Abdulrahman A

2018-04-01

Aim: The aim of this study is (1) to inspect any difference in mandibular arch widths between males and females in class I and class II division 1 (class malocclusions using cone-beam computed tomography (CBCT), (2) to compare the mandibular dental and basal widths between the two groups, and (3) to investigate any possible correlation between dental and basal arch widths in both groups. Materials and methods: The CBCT images of 68 patients aged between 18 and 25 years consisted of 34 class I (17 males and 17 females) and 34 class (17 males and 17 females) who were recruited at the Department of Orthodontics, University of Damascus Dental School (Syria). Using on-demand three-dimensional (3D) on axial views, facial axis points for dental measurements and basal bone center (BBC) points for basal measurements were identified on lower canines and first molars. Dental and basal intercanine width (ICW) and intermolar width (IMW) were measured. Results: Independent t-test showed a statistically significant difference between males and females in several variables in both groups and a statistically significant difference between class I and class groups in the basal ICW for both genders and in the dental ICW for females only (p class I group, Pearson's correlation coefficients between dental and basal measurements showed a strong correlation in the IMW for both genders (r > 0.73; p class group, a moderate correlation in females' IMW (r = 0.67; p Class I patients had larger ICW than class II-1 patients in all measurements and had narrower IMW than class in most measurements for both genders. There were moderate-to-strong correlations between dental and basal dimensions. BBC points might be landmarks that accurately represent the basal bone arch. Clinical significance: CBCT-based assessments of dental and basal arch dimensions provide a great opportunity to accurately evaluate these aspects, to enhance clinicians' decisions regarding proper tooth movements, and to achieve

Accuracy of complete-arch dental impressions: a new method of measuring trueness and precision.

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Ender, Andreas; Mehl, Albert

2013-02-01

A new approach to both 3-dimensional (3D) trueness and precision is necessary to assess the accuracy of intraoral digital impressions and compare them to conventionally acquired impressions. The purpose of this in vitro study was to evaluate whether a new reference scanner is capable of measuring conventional and digital intraoral complete-arch impressions for 3D accuracy. A steel reference dentate model was fabricated and measured with a reference scanner (digital reference model). Conventional impressions were made from the reference model, poured with Type IV dental stone, scanned with the reference scanner, and exported as digital models. Additionally, digital impressions of the reference model were made and the digital models were exported. Precision was measured by superimposing the digital models within each group. Superimposing the digital models on the digital reference model assessed the trueness of each impression method. Statistical significance was assessed with an independent sample t test (α=.05). The reference scanner delivered high accuracy over the entire dental arch with a precision of 1.6 ±0.6 µm and a trueness of 5.3 ±1.1 µm. Conventional impressions showed significantly higher precision (12.5 ±2.5 µm) and trueness values (20.4 ±2.2 µm) with small deviations in the second molar region (PDigital impressions were significantly less accurate with a precision of 32.4 ±9.6 µm and a trueness of 58.6 ±15.8µm (Pdigital models were visible across the entire dental arch. The new reference scanner is capable of measuring the precision and trueness of both digital and conventional complete-arch impressions. The digital impression is less accurate and shows a different pattern of deviation than the conventional impression. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Incisor and molar overjet, arch contraction, and molar relationship in the mixed dentition in repaired complete unilateral cleft lip and palate: A qualitative and quantitative appraisal.

Science.gov (United States)

Disthaporn, Suteeta; Suri, Sunjay; Ross, Bruce; Tompson, Bryan; Baena, Diogenes; Fisher, David; Lou, Wendy

2017-07-01

To compare the mixed dentition incisor and molar overjet, severity of contraction of the dental arch, and the sagittal molar relationship on the cleft side vs the noncleft side in children with repaired complete unilateral cleft of the lip and palate (UCLP). Orthodontic records taken prior to orthodontic preparation for alveolar bone grafting were screened to select study casts from patients with nonsyndromic repaired complete UCLP who did not have mandibular skeletal or dental asymmetry. The study sample comprised dental casts from 74 children aged 8.9 ± 1 years. Standardized digital photographs were acquired at 1:1 magnification. A coordinate system was developed using digital image-processing software (Photoshop CS4 and Adobe Illustrator). Incisor and molar overjet, Angle's classification, and arch contraction were recorded. Descriptive statistics, paired t-tests, and kappa statistics were used to compare the cleft and noncleft sides. A negative overjet of -1 to -5 mm was often present at the incisors, with greater frequency and magnitude on the cleft side. Class II molar relation was more frequent on the cleft side (61.1%) than on the noncleft side (47.2%). Significantly greater contraction of the cleft side deciduous canine and deciduous first molar was noted, while the difference was very minor at the first permanent molar. Cleft side maxillary arch contraction was most severe in the deciduous canine and first deciduous molar region and progressively less severe in the posterior region of the arch. A greater frequency and severity of negative overjet and Class II molar relationship was seen on the cleft side.

[Effect of removable partial dentures restoration on oral health-related quality of life of patients with shortened dental arch].

Science.gov (United States)

Fu, Zhen-nan; Lin, Xue-feng

2013-11-01

To assess the effect of removable partial dentures (PRD) restoration on oral health-related quality of life (OHRQOL) of subjects with shortened dental arches (SDA) using the Chinese version of the Oral Health Impact Profile (OHIP-14). Consecutive patients with shortened dental arches were recruited from the Department of Prosthodontics, Foshan Chancheng Hospital of Stomatology. The Chinese version of OHIP-14 was administered to each subject before treatment and after treatment. The subjective outcomes of removable partial dentures therapy on SDA were collected and the pre- and post-treatment scores of the Chinese version of OHIP-14 were compared. After treatment, significant decrease in patients' total score of OHRQOL [before: 9 (6, 12) ; after: 4 (2.25, 6)] was detected, as well as physical pain subscale, physical disability subscale and handicap subscale; and the score of OHRQOL in function limitation subscale increased [before: 0(0,0); after: 2(1, 2)]. The main impacts of shortened dental arch with intact anterior region affecting patients' OHRQOL are physical disability.From a quality-of-life perspective, patients with SDA can perceive benefits from RPD.

Miniscrew-assisted rapid palatal expansion for managing arch perimeter in an adult patient

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Amanda Carneiro da Cunha

Full Text Available ABSTRACT Introduction: Etiology of dental crowding may be related to arch constriction in diverse dimensions, and an appropriate manipulation of arch perimeter by intervening in basal bone discrepancies cases, may be a key for crowding relief, especially when incisors movement is limited due to underlying pathology, periodontal issues or restrictions related to soft tissue profile. Objectives: This case report illustrates a 24-year old woman, with maxillary transverse deficiency, upper and lower arches crowding, Class II, division 1, subdivision right relationship, previous upper incisors traumatic episode and straight profile. A non-surgical and non-extraction treatment approach was feasible due to the miniscrew-assisted rapid palatal expansion technique (MARPE. Methods: The MARPE appliance consisted of a conventional Hyrax expander supported by four orthodontic miniscrews. A slow expansion protocol was adopted, with an overall of 40 days of activation and a 3-month retention period. Intrusive traction miniscrew-anchored mechanics were used for correcting the Class II subdivision relationship, managing lower arch perimeter and midline deviation before including the upper central incisors. Results: Post-treatment records show an intermolar width increase of 5 mm, bilateral Class I molar and canine relationships, upper and lower crowding resolution, coincident dental midlines and proper intercuspation. Conclusions: The MARPE is an effective treatment approach for managing arch-perimeter deficiencies related to maxillary transverse discrepancies in adult patients.

Retrospective analysis of 56 edentulous dental arches restored with 344 single-stage implants using an immediate loading fixed provisional protocol: statistical predictors of implant failure.

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Kinsel, Richard P; Liss, Mindy

2007-01-01

The purpose of this retrospective study was to evaluate the effects of implant dimensions, surface treatment, location in the dental arch, numbers of supporting implant abutments, surgical technique, and generally recognized risk factors on the survival of a series of single-stage Straumann dental implants placed into edentulous arches using an immediate loading protocol. Each patient received between 4 and 18 implants in one or both dental arches. Periapical radiographs were obtained over a 2- to 10-year follow-up period to evaluate crestal bone loss following insertion of the definitive metal-ceramic fixed prostheses. Univariate tests for failure rates as a function of age ( or = 60 years), gender, smoking, bone grafting, dental arch, surface type, anterior versus posterior, number of implants per arch, and surgical technique were made using Fisher exact tests. The Cochran-Armitage test for trend was used to evaluate the presence of a linear trend in failure rates regarding implant length and implant diameter. Logistic regression modeling was used to determine which, if any, of the aforementioned factors would predict patient and implant failure. A significance criterion of P = .05 was utilized. Data were collected for 344 single-stage implants placed into 56 edentulous arches (39 maxillae and 17 mandibles) of 43 patients and immediately loaded with a 1-piece provisional fixed prosthesis. A total of 16 implants failed to successfully integrate, for a survival rate of 95.3%. Increased rates of failure were associated with reduced implant length, placement in the posterior region of the jaw, increased implant diameter, and surface treatment. Implant length emerged as the sole significant predictor of implant failure. In this retrospective analysis of 56 consecutively treated edentulous arches with multiple single-stage dental implants loaded immediately, reduced implant length was the sole significant predictor of failure.

Long-term follow-up indicates unimpaired oral health-related quality of life for people having shortened dental arches

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Gerritsen, A.E.; Witter, D.J.; Creugers, N.H.J.

2017-01-01

OBJECTIVES: To assess and analyse OHRQoL of people with shortened dental arches (SDA) in a long-term cohort study. METHODS: All participants of a long-term cohort study on SDA who were still attending the university dental clinic and still had an SDA (SDA group) with 3-5 posterior occluding pairs

Comparison of dental arch dimensions in models of preschool children with cleft lip/palate repaired by means of surgery alone versus controls.

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Burhan, Ahmad S; Nawaya, Fehmieh R

2016-09-01

Cleft lip and palate (CLP) anomaly is one of the most prevalent congenital defects causing disturbances of dental arch dimensions. This study aimed at investigating differences in these dimensions between preschool children with cleft lip/palate and a matched control group representing healthy individuals with normal occlusion (NO). The sample of this cross-sectional analytical study consisted of 108 plaster models of children aged from 4 to 5.5 years. They were divided into five groups: the cleft lip group, the cleft palate (CP) group, the unilateral cleft lip and palate group, the bilateral cleft lip and palate group, and the NO group. The NO group was used as a control group. All cleft-affected children were treated only with surgery. Dental arch length and widths were measured. The dental arch dimensions of the cleft lip group were nearly similar to those in the controls. Moreover, the mandibular transverse widths of the CP group were close to those in the controls. However, the mandibular arch length and all maxillary dimensions of the CP group were smaller than those in the controls. In the unilateral cleft lip and palate group, the arch lengths in both jaws and the maxillary transverse widths were smaller than those in the controls, whereas the mandibular transverse widths were similar to those in the controls. In the bilateral cleft lip and palate group, the arch lengths in both jaws were close to those in the controls, but both arches were narrower than those in the controls. The various types of CLP were found to be associated with differences in most maxillary and some mandibular arch dimensions. These data can be used for cleft patient counseling and treatment planning.

Shape model of the maxillary dental arch using Fourier descriptors with an application in the rehabilitation for edentulous patient.

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Rijal, Omar M; Abdullah, Norli A; Isa, Zakiah M; Noor, Norliza M; Tawfiq, Omar F

2013-01-01

The knowledge of teeth positions on the maxillary arch is useful in the rehabilitation of the edentulous patient. A combination of angular (θ), and linear (l) variables representing position of four teeth were initially proposed as the shape descriptor of the maxillary dental arch. Three categories of shape were established, each having a multivariate normal distribution. It may be argued that 4 selected teeth on the standardized digital images of the dental casts could be considered as insufficient with respect to representing shape. However, increasing the number of points would create problems with dimensions and proof of existence of the multivariate normal distribution is extremely difficult. This study investigates the ability of Fourier descriptors (FD) using all maxillary teeth to find alternative shape models. Eight FD terms were sufficient to represent 21 points on the arch. Using these 8 FD terms as an alternative shape descriptor, three categories of shape were verified, each category having the complex normal distribution.

One-stage closure of isolated cleft palate with the Veau-Wardill-Kilner V to Y pushback procedure or the Cronin modification. II. Height, weight and comparison of dental arches.

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Heliövaara, A; Pere, A; Ranta, R

1994-03-01

The body height and weight, and sizes of dental arches in 116 patients with isolated cleft palate were evaluated at 16.9-20.6 years of age. One-stage closure of the soft and hard palate had been done at a mean age of 1.8 years using the Veau-Wardill-Kilner or the Cronin mucoperiosteal palatal V-Y pushback technique. The height attained in both the boys (177.6 cm) and the girls (165.7 cm) was similar to that in the general adult population, even though half of the boys had not reached their final height. The median relative weight for height and sex was 6%. There were no significant differences in dental arch measurements depending on the method of operation but the more palatal operations done the shorter the maxillary and mandibular dental arch widths. The extent of cleft made a significant difference, larger clefts having narrower palatal intercanine widths. Dental arch dimensions were consistently larger in boys than in girls.

Mastication in subjects with extremely shortened dental arches rehabilitated with removable partial dentures.

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Arce-Tumbay, Jackelyn; Sanchez-Ayala, Alfonso; Sotto-Maior, Bruno Salles; Senna, Plinio Mendes; Campanha, Nara Hellen

2011-01-01

Mastication was evaluated in subjects presenting extremely shortened dental arches (ESDAs) rehabilitated with mandibular free-end removable partial dentures (RPDs). Subjects were divided into four groups (n = 10): those with a complete dentition, those with ESDAs, and those with ESDAs who were rehabilitated with an RPD, who were evaluated both with and without their prostheses. Mastication was measured through masticatory performance, time, and ability. RPD wearers showed higher masticatory performance (P mastication in ESDA subjects but without achieving normal mastication levels.

In vivo precision of conventional and digital methods of obtaining complete-arch dental impressions.

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Ender, Andreas; Attin, Thomas; Mehl, Albert

2016-03-01

Digital impression systems have undergone significant development in recent years, but few studies have investigated the accuracy of the technique in vivo, particularly compared with conventional impression techniques. The purpose of this in vivo study was to investigate the precision of conventional and digital methods for complete-arch impressions. Complete-arch impressions were obtained using 5 conventional (polyether, POE; vinylsiloxanether, VSE; direct scannable vinylsiloxanether, VSES; digitized scannable vinylsiloxanether, VSES-D; and irreversible hydrocolloid, ALG) and 7 digital (CEREC Bluecam, CER; CEREC Omnicam, OC; Cadent iTero, ITE; Lava COS, LAV; Lava True Definition Scanner, T-Def; 3Shape Trios, TRI; and 3Shape Trios Color, TRC) techniques. Impressions were made 3 times each in 5 participants (N=15). The impressions were then compared within and between the test groups. The cast surfaces were measured point-to-point using the signed nearest neighbor method. Precision was calculated from the (90%-10%)/2 percentile value. The precision ranged from 12.3 μm (VSE) to 167.2 μm (ALG), with the highest precision in the VSE and VSES groups. The deviation pattern varied distinctly according to the impression method. Conventional impressions showed the highest accuracy across the complete dental arch in all groups, except for the ALG group. Conventional and digital impression methods differ significantly in the complete-arch accuracy. Digital impression systems had higher local deviations within the complete arch cast; however, they achieve equal and higher precision than some conventional impression materials. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Analysis of dental arch relationships in Swedish unilateral cleft lip and palate subjects: 20-year longitudinal consecutive series treated with delayed hard palate closure.

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Lilja, Jan; Mars, Michael; Elander, Anna; Enocson, Lars; Hagberg, Catharina; Worrell, Emma; Batra, Puneet; Friede, Hans

2006-09-01

To evaluate the dental arch relationships for a consecutive series from Goteborg, Sweden, who had delayed hard palate closure. Retrospective study. Sahlgrenska University Hospital, Goteborg, Sweden. The dental study models of 104 consecutive unilateral cleft lip and palate subjects. The study cohort was born between 1979 and 1994. Longitudinal records were available at ages 5 (n = 94), 10 (n = 97), 16 (n = 59), and 19 years (n = 46). Five assessors rated models according to the GOSLON Yardstick on two separate occasions each. These patients had been operated upon according to the Goteborg protocol of delayed hard palate closure (at age 8 years). 85% of subjects were rated in groups 1 and 2 (excellent or very good outcome), 12% were rated in group 3 (satisfactory), and 3% were assigned to group 4 (poor). No patients presented in Group 5 (very poor). Weighted kappa statistics for double determination of Yardstick allocation for five assessors demonstrated values between .65 and .90 for interrater agreement (good/very good) and between .70 and .90 for intrarater agreement (very good). Delayed hard palate closure as practiced in Goteborg since 1979 has produced the best GOSLON Yardstick ratings in a consecutive series of patients ever recorded worldwide, since the Yardstick was first used in 1983. However, it is noteworthy that a new protocol has been introduced in Goteborg since 1994, in which hard palate closure is done at 3 years due to concerns regarding speech.

Mandibular dental arch short and long-term spontaneous dentoalveolar changes after slow or rapid maxillary expansion: a systematic review

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Arthur César de Medeiros Alves

Full Text Available ABSTRACT Objective: The aim of this systematic review was to analyze the short and long-term spontaneous dentoalveolar changes of the mandibular dental arch after slow (SME or rapid (RME maxillary expansion in the mixed and early permanent dentitions. Methods: An electronic search was performed in the following databases: PubMed/Medline, Cochrane Library, Scopus, Embase and Web of Science. Eligibility criteria for article selection included randomized controlled trials and prospective studies written in English, with no restriction of year of publication, involving patients who underwent SME or RME during the mixed or early permanent dentitions. A double-blind search of articles was performed by two reviewers. Initially, the title and the abstract of the studies were read, and their references were also hand-searched for possible missing studies. A methodological quality scoring scale was used to analyze the selected articles. Results: The search retrieved 373 articles, but only 6 were selected for review after application of the eligibility and exclusion criteria. Non-clinically significant spontaneous dentoalveolar changes of approximately 1mm were found in the mandibular dental arch in the short and long-term, after slow or rapid maxillary expansions. Furthermore, no significant differences were found between treated and control groups. Conclusions: There is enough evidence to conclude that negligible short and long-term spontaneous dentoalveolar changes tend to occur in the mandibular dental arch after SME or RME in the mixed and early permanent dentitions. More randomized studies with appropriate control group are required to better evaluate this issue.

Is the shortened dental arch still a satisfactory option?

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Manola, M; Hussain, F; Millar, B J

2017-07-21

Aims Dental practitioners may hold the view that missing posterior teeth should be replaced to ensure a healthy masticatory system and satisfactory oral function. However, the shortened dental arch (SDA) concept is still in use, but after 35 years is it acceptable? This review searches the literature for the evidence and opinions regarding the suitability of the SDA as a current treatment modality.Methods Medline and PubMed databases were searched for relevant terms, all the abstracts were assessed and articles selected according to the pre-set exclusion and inclusion criteria.Results The search yielded 1,895 articles and after the assessment of the abstracts and application of the exclusion and inclusion criteria, 44 articles were selected for this review. These included 11 cohort studies, two longitudinal studies, two animal studies, three cross sectional studies, eight clinical studies and 18 case control studies. There appears to be a trend over the past three decades for more papers to be opposed to the SDA concept.Conclusion Evidence that the SDA causes pathology is lacking. Clinicians, healthcare authorities and patients have shown favourable attitudes towards the SDA and this continues, although there is an increase in studies opposing the concept and some are dissatisfied with this option. The concept remains viable particularly for the medically compromised patient or where restorations are considered unsuitable but further more specific studies are warranted.

Anterior crossbite, dental arch dimensions, and later need for orthognathic surgery in 6-year-old children with unilateral cleft lip and palate.

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Heliövaara, Arja; Leikola, Junnu; Rautio, Jorma

2014-09-01

Objective : Six-year-old children with unilateral cleft lip and palate were examined to compare the prevalence of anterior crossbite and dental arch dimensions of those who later needed orthognathic surgery with the prevalence of those who did not. Design : Retrospective longitudinal study. Patients : A total of 68 consecutive nonsyndromic patients with unilateral cleft lip and palate (44 boys, 24 girls). Main Outcome Measures : Children with unilateral cleft lip and palate whose palates had been closed in one stage by the Veau-Wardill-Kilner or Cronin-Brauer V-Y pushback techniques were analyzed from dental casts taken at a mean age of 6.1 years (range, 5.7 to 6.8 years) before orthodontic treatment or bone grafting. The need for orthognathic surgery in these patients was determined from hospital records at the mean age of 18.2 years (range, 15.6 to 20.2 years). Student's t test and chi-square test were used in statistical analyses. Results : The prevalence of anterior crossbite was 62% (one or both central incisors in full crossbite). The prevalence was higher (75% versus 53%) in children later needing orthognathic surgery (28 of 68, 41%), but the difference was not significant. Nor were there significant differences in dental arch measurements between children who later needed osteotomies and those who did not or between the two modifications of the primary palatal pushback operations. Conclusions : The prevalence of anterior crossbite and the dental arch dimensions did not differ between 6-year-old children with unilateral cleft lip and palate who later needed orthognathic surgery and those who did not.

Evaluation of arch width variations among different skeletal patterns in South Indian population.

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Prasad, Mandava; Kannampallil, Senny Thomas; Talapaneni, Ashok Kumar; George, Suja Ani; Shetty, Sharath Kumar

2013-01-01

Anterior cranial base can be taken as a reference line (SN) to determine the steepness of mandibular plane. Subjects with high mandibular plane angle tend to have a long face and one with low MP-SN angle has a shorter face. This study was done to investigate if dental arch widths correlated with vertical facial types and if there are any differences in arch widths between untreated male and female adults in South Indian population. Lateral cephalogram and dental casts were obtained from 180 untreated South Indian adults (90 males and 90 females) above 18 year old with no cross bite, minimal crowding and spacing. The angle between the anterior cranial base and the mandibular plane was measured on lateral cephalogram of each patient. Dental casts were used to obtain comprehensive dental measurements including maxillary and mandibular inter canine, inter premolar and inter molar widths, as well as amount of crowding or spacing. The results showed that male arch widths were significantly larger than those of females (P population. The results obtained in our study when compared with studies done in other population groups showed that there is difference in inter arch widths according to ethnicity and race. It was concluded that the dental arch width is associated with gender, race and vertical facial morphology. Thus using individualized arch wires according to each patient's pre treatment arch form and width is suggested during orthodontic treatment.

Interdental Spacing and Dental Caries in the Primary Dentition of 4-6 Year Old Children

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G. Babu Kl

2012-01-01

Full Text Available Objective: There are various risk factors which play an essential role in the multifactorial disease “dental caries.” Although absence of interdental spaces in the primary dentition may increase the risk of dental caries, not many studies have been carried out to assess this correlation. This study was performed to assess the relationship between interdental spacing and dental caries in primary dentition.Materials and Methods: Five hundred 4-6 year-old children were enrolled into this study. Dental caries was recorded using the criteria given by Warren et al. Following this, impressions were made for the upper and lower arches and dental casts were poured. Interdental spaces were measured on the dental casts using a digital verniercaliper. The data obtained were subjected to statistical analysis.Results: The number of sites with interdental spaces was higher in the maxillary arch in comparison to the mandibular arch. The highest number of interdental spaces was observed between the maxillary anteriors. The number of demineralized, but non-cavitated tooth surfaces (d1were higher than the number of cavitated tooth surfaces. This difference was significant in the mandibular anterior segment. Dental caries showed a negative correlation with interdental spacing. A significant correlation was found between dental caries and interdental spacing in the posterior segment of the mandibular arch.Conclusion: This study showed that children with no interdental spacing in the primary dentition are at higher risk for dental caries.Key Words: Dental Caries; Interdental Spaces; Interproximal Caries

Botulinum Toxin Type A as Preoperative Treatment for Immediately Loaded Dental Implants Placed in Fresh Extraction Sockets for Full-Arch Restoration of Patients With Bruxism.

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Mijiritsky, Eitan; Mortellaro, Carmen; Rudberg, Omri; Fahn, Miri; Basegmez, Cansu; Levin, Liran

2016-05-01

The aim of the present report was to describe the use of Botulinum toxin type A as preoperative treatment for immediately loaded dental implants placed in fresh extraction sockets for full-arch restoration of patients with bruxism. Patients with bruxism who were scheduled to receive immediately loaded full-arch implant supported fixed restorations were included in this retrospective clinical report. To reduce the occlusal forces applied in patients with bruxism, Botulinum toxin type A was introduced prior to the implant placement procedure. Patients were followed and implant survival as well as peri-implant bone level was assessed in each periodic follow-up visit. Adverse effects were also recorded. A control group with no use of Botulinum toxin was evaluated as well. A total of 26 patients (13 test and 13 control), with bruxism, aged 59.15 ± 11.43 years on average were included in this retrospective report and received immediately loaded dental implants placed in fresh extraction sockets for full-arch restoration. The test group treatment preceded by Botulinum toxin type A injection. Maxillary arches were supported by 8 to 10 implants while the mandibular arch was supported by 6 implants. All surgeries went uneventfully and no adverse effects were observed. The average follow-up time was 32.5 ± 10.4 months (range, 18-51). In the test group, no implant failures were recorded. One patient presented with 1 to 2 mm bone loss around 4 of the implants; the other implants presented with stable bone level. In the control group 1 patient lost 2 implants and another demonstrated 2 mm bone loss around 3 of the implants. The preoperative use of Botulinum toxin in patients with bruxism undergoing full-arch rehabilitation using immediately loaded dental implants placed in fresh extraction sockets seems to be a technique that deserves attention. Further long-term, large-scale randomized clinical trials will help to determine the additional benefit of this suggested

Maxillary Arch Dimension Changes of 3-5 Years Old Filipino Children

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Abdol Hamid Zafarmand

2014-11-01

Full Text Available Background: The purpose of this study was to assess the dental arch dimensions in primary dentition of 3-5 years old Filipino children and determining the existence of sexual dimorphism.Materials and Methods: In this descriptive study, 60 Filipino preschool children aged 3-5 years old were selected from Manila city. Study casts were used for measurements of 3 arch dimensions: bicanine width, bimolar width, and arch length. The analyses were performed to compare values within age-groups and within gender-groups, besides reporting mean and standard deviations. The data were subjected to One-way ANOVA and Student t-test.Results: Significant differences were observed regarding dental arch dimensions among different ages and genders (p<0.05. Comparison between genders showed a statistically significant difference in bicanine width at the age of 4 (p=0.04, in bimolar width at age of 5 (p=0.006, and in arch length at age of 4 (p=0.03 and 5 (p=0.02. Differences within male group for different ages showed only arch length dimension was statistically significant (p=0.021. In females, however the comparison between age-groups also revealed a statistically significant difference in bicanine (p= 0.016 and bimolar widths (p=0.027 dimensions.Conclusion: The present study showed that dental arch dimensions, vary among different ages and genders of children. It also showed that a sexual dimorphism does exist between the gender groups.

In-vitro evaluation of the accuracy of conventional and digital methods of obtaining full-arch dental impressions.

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Ender, Andreas; Mehl, Albert

2015-01-01

To investigate the accuracy of conventional and digital impression methods used to obtain full-arch impressions by using an in-vitro reference model. Eight different conventional (polyether, POE; vinylsiloxanether, VSE; direct scannable vinylsiloxanether, VSES; and irreversible hydrocolloid, ALG) and digital (CEREC Bluecam, CER; CEREC Omnicam, OC; Cadent iTero, ITE; and Lava COS, LAV) full-arch impressions were obtained from a reference model with a known morphology, using a highly accurate reference scanner. The impressions obtained were then compared with the original geometry of the reference model and within each test group. A point-to-point measurement of the surface of the model using the signed nearest neighbour method resulted in a mean (10%-90%)/2 percentile value for the difference between the impression and original model (trueness) as well as the difference between impressions within a test group (precision). Trueness values ranged from 11.5 μm (VSE) to 60.2 μm (POE), and precision ranged from 12.3 μm (VSE) to 66.7 μm (POE). Among the test groups, VSE, VSES, and CER showed the highest trueness and precision. The deviation pattern varied with the impression method. Conventional impressions showed high accuracy across the full dental arch in all groups, except POE and ALG. Conventional and digital impression methods show differences regarding full-arch accuracy. Digital impression systems reveal higher local deviations of the full-arch model. Digital intraoral impression systems do not show superior accuracy compared to highly accurate conventional impression techniques. However, they provide excellent clinical results within their indications applying the correct scanning technique.

Intraoral gothic arch tracing.

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Rubel, Barry; Hill, Edward E

2011-01-01

In order to create optimum esthetics, function and phonetics in complete denture fabrication, it is necessary to record accurate maxillo-mandibular determinants of occlusion. This requires clinical skill to establish an accurate, verifiable and reproducible vertical dimension of occlusion (VDO) and centric relation (CR). Correct vertical relation depends upon a consideration of several factors, including muscle tone, inter-dental arch space and parallelism of the ridges. Any errors made while taking maxillo-mandibular jaw relation records will result in dentures that are uncomfortable and, possibly, unwearable. The application of a tracing mechanism such as the Gothic arch tracer (a central bearing device) is a demonstrable method of determining centric relation. Intraoral Gothic arch tracers provide the advantage of capturing VDO and CR in an easy-to-use technique for practitioners. Intraoral tracing (Gothic arch tracing) is a preferred method of obtaining consistent positions of the mandible in motion (retrusive, protrusive and lateral) at a comfortable VDO.

[A new method to orthodontically correct dental occlusal plane canting: wave-shaped arch].

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Zheng, X; Hu, X X; Ma, N; Chen, X H

2017-02-18

To introduce a technique of second order wave-shaped arch wire to orthodontically treat dental occlusal plane canting (DOPC) with left-right interactive anchorage, and to test its clinical efficacy. Among the permanent dentition malocclusion patients who showed no obvious facial asymmetry, we screened for patients who showed anterior occlusal plane canting (AOPC) after routine orthodontic examination, treatment planning, MBT fixed appliance installation and serial arch wires alignment. Each patient had been clinically appraised in frontal view by 2 orthodontists and the patient him/herself; if all 3 agreed that the AOPC was obvious, the patient was included. By this means, we included 37 patients, including 10 males and 27 females; the average age was (21.9±5.2) years. To correct AOPC, opposite direction equal curvature second order rocking-chair curve was bent on each side of 0.46 mm×0.56 mm stainless steel edgewise wire. With reference to normal occlusal plane, a curve toward the occlusal surface was made to extrude under-erupted teeth on one side while a curve toward the gingiva was made to intrude over-erupted teeth on the other side, so that the arch wire was made into a wave shape in vertical dimension. Before and after application of wave-shaped arch wire, frontal facial photographs were taken when the patient's mouth was open slightly with lips retracted to show anterior occlusal plane (AOP) clearly. An AOP was constructed by connecting the center of the slot in the medial edge of canine bracket on each side in the photograph. The angles between the bipupillary plane(BPP) and the constructed AOP were measured in ImageJ1-48v software and the angle differences before and after treatment were compared with paired Wilcoxon test in SPSS 10.0 software. The wave-shaped arch could correct AOPC effectively in 3 to 10 months time with an average of 5.5±1.7 months; the angles between AOP and BBP before treatment ranged from 2.90° to 6.12° with a median of 4.01�

The randomized shortened dental arch study (RaSDA: design and protocol

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Kern Matthias

2010-02-01

Full Text Available Abstract Background Various treatment options for the prosthetic treatment of jaws where all molars are lost are under discussion. Besides the placement of implants, two main treatment types can be distinguished: replacement of the missing molars with removable dental prostheses and non-replacement of the molars, i.e. preservation of the shortened dental arch. Evidence is lacking regarding the long-term outcome and the clinical performance of these approaches. High treatment costs and the long time required for the treatment impede respective clinical trials. Methods/design This 14-center randomized controlled investigator-initiated trial is ongoing. Last patient out will be in 2010. Patients over 35 years of age with all molars missing in one jaw and with at least both canines and one premolar left on each side were eligible. One group received a treatment with removable dental prostheses for molar replacement (treatment A. The other group received a treatment limited to the replacement of all missing anterior and premolar teeth using fixed bridges (treatment B. A pilot trial with 32 patients was carried out. Two hundred and fifteen patients were enrolled in the main trial where 109 patients were randomized for treatment A and 106 for treatment B. The primary outcome measure is further tooth loss during the 5-year follow-up. The secondary outcome measures encompassed clinical, technical and subjective variables. The study is funded by the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG WA 831/2-1, 2-2, 2-3, 2-4, 2-5. Discussion The particular value of this trial is the adaptation of common design components to the very specific features of complex dental prosthetic treatments. The pilot trial proved to be indispensable because it led to a number of adjustments in the study protocol that considerably improved the practicability. The expected results are of high clinical relevance and will show the efficacy of two common

Association between breastfeeding duration, non-nutritive sucking habits and dental arch dimensions in deciduous dentition: a cross-sectional study

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Agarwal, Shiv Shankar; Nehra, Karan; Sharma, Mohit; Jayan, Balakrishna; Poonia, Anish; Bhattal, Hiteshwar

2014-01-01

Background This cross-sectional retrospective study was conducted to determine association between breastfeeding duration, non-nutritive sucking habits, dental arch transverse diameters, posterior crossbite and anterior open bite in deciduous dentition. Methods 415 children (228 males and 187 females), 4 to 6 years old, from a mixed Indian population were clinically examined. Based on written questionnaire answered by parents, children were divided into two groups: group 1 (breastfed for

Loss of space and dental arch length after the loss of the lower first primary molar: a longitudinal study.

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Cuoghi, O A; Bertoz, F A; de Mendonca, M R; Santos, E C

1998-01-01

The premature loss of primary teeth may harm the normal occlusal development, although there are debates relating to the necessity of using space maintainer appliances. The aim of the study is to evaluate the changes in the dental arch perimeter and the space reduction after the premature loss of the lower first primary molar in the mixed dentition stage. The sample consists of 4 lower arch plaster models of 31 patients, within the period of pre-extraction, 6, 12 and 18 months after the lower first primary molar extraction. A reduction of space was of noted with the cuspid dislocation and the permanent incisors moving toward the space of the extraction site. It was concluded that the lower first molar primary premature loss, during the mixed dentition, implicates an immediate placement of a space maintainer.

Evaluation of maxillary arch morphology in children with unilaterally impacted incisors via three-dimensional analysis of digital dental casts: a controlled study.

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Pavoni, Chiara; Franchi, Lorenzo; Buongiorno, Marco; Cozza, Paola

2016-01-01

The purpose of this work was to analyze variations in maxillary arch dimensions in subjects presenting unilaterally impacted maxillary permanent central incisors compared with a control group of subjects without eruption anomalies. A group of 23 Caucasian children [8 females and 15 males, mean age 9.7 years, standard deviation (SD) 1.6 years] displaying unilaterally impacted maxillary permanent central incisors (impacted incisor group: IIG) were compared with a control group (CG) of 23 subjects (9 females; 14 males, mean age 8.8 years, SD 1.9 years) presenting no eruption disorders. Pretreatment dental casts were taken from each subject and the upper arch was scanned using a three-dimensional scanner. Linear measurements were taken on each digital model to analyze maxillary arch dimensions. Significant between-group differences were tested with the Student's t test (p < 0.05). The transverse and sagittal upper-arch measurements were significantly smaller in the IIG than in the CG. In particular, the anterior arch was 1.35 mm shorter in the IIG, while intercanine width was decreased by 2.51 mm on the impacted side. Children revealing unilaterally impacted maxillary central incisors demonstrated a significantly constricted maxillary transverse width and shorter arch on the impacted side compared with subjects with no eruption disorders.

The randomized shortened dental arch study: tooth loss over five years.

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Walter, M H; Hannak, W; Kern, M; Mundt, T; Gernet, W; Weber, A; Wöstmann, B; Stark, H; Werner, D; Hartmann, S; Range, U; Jahn, F; Passia, N; Pospiech, P; Mitov, G; Brückner, J; Wolfart, S; Busche, E; Luthardt, R G; Heydecke, G; Marré, B

2013-04-01

The study was designed to provide clinical outcome data for two treatments of the shortened dental arch (SDA). In a multicenter randomized controlled clinical trial, patients with complete molar loss in one jaw were provided with either a partial removable dental prosthesis (PRDP) retained with precision attachments or treated according to the SDA concept preserving or restoring a premolar occlusion. No implants were placed. The primary outcome was tooth loss. Of 152 treated patients, 132 patients reached the 5-year examination. Over 5 years, 38 patients experienced tooth loss. For the primary outcome tooth loss, the Kaplan-Meier survival rates at 5 years were 0.74 (95% CI 0.64, 0.84) in the PRDP group and 0.74 (95% CI 0.63, 0.85) in the SDA group. For tooth loss in the study jaw, the survival rates at 5 years were 0.88 (95% CI 0.80, 0.95) in the PRDP group and 0.84 (95% CI 0.74, 0.93) in the SDA group. The differences were not significant. No Cox regression models of appropriate fit explaining tooth loss on the patient level could be found. The overall treatment goals of a sustainable oral rehabilitation and the avoidance of further tooth loss over longer periods were not reliably achievable. The influence of the type of prosthetic treatment on tooth loss might have been overestimated. Regarding our results, the patient's view will gain even more importance in the clinical decision between removable and fixed restorations in SDAs.

3D space analysis of dental models

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Chuah, Joon H.; Ong, Sim Heng; Kondo, Toshiaki; Foong, Kelvin W. C.; Yong, Than F.

2001-05-01

Space analysis is an important procedure by orthodontists to determine the amount of space available and required for teeth alignment during treatment planning. Traditional manual methods of space analysis are tedious and often inaccurate. Computer-based space analysis methods that work on 2D images have been reported. However, as the space problems in the dental arch exist in all three planes of space, a full 3D analysis of the problems is necessary. This paper describes a visualization and measurement system that analyses 3D images of dental plaster models. Algorithms were developed to determine dental arches. The system is able to record the depths of the Curve of Spee, and quantify space liabilities arising from a non-planar Curve of Spee, malalignment and overjet. Furthermore, the difference between total arch space available and the space required to arrange the teeth in ideal occlusion can be accurately computed. The system for 3D space analysis of the dental arch is an accurate, comprehensive, rapid and repeatable method of space analysis to facilitate proper orthodontic diagnosis and treatment planning.

Accuracy and precision of polyurethane dental arch models fabricated using a three-dimensional subtractive rapid prototyping method with an intraoral scanning technique.

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Kim, Jae-Hong; Kim, Ki-Baek; Kim, Woong-Chul; Kim, Ji-Hwan; Kim, Hae-Young

2014-03-01

This study aimed to evaluate the accuracy and precision of polyurethane (PUT) dental arch models fabricated using a three-dimensional (3D) subtractive rapid prototyping (RP) method with an intraoral scanning technique by comparing linear measurements obtained from PUT models and conventional plaster models. Ten plaster models were duplicated using a selected standard master model and conventional impression, and 10 PUT models were duplicated using the 3D subtractive RP technique with an oral scanner. Six linear measurements were evaluated in terms of x, y, and z-axes using a non-contact white light scanner. Accuracy was assessed using mean differences between two measurements, and precision was examined using four quantitative methods and the Bland-Altman graphical method. Repeatability was evaluated in terms of intra-examiner variability, and reproducibility was assessed in terms of inter-examiner and inter-method variability. The mean difference between plaster models and PUT models ranged from 0.07 mm to 0.33 mm. Relative measurement errors ranged from 2.2% to 7.6% and intraclass correlation coefficients ranged from 0.93 to 0.96, when comparing plaster models and PUT models. The Bland-Altman plot showed good agreement. The accuracy and precision of PUT dental models for evaluating the performance of oral scanner and subtractive RP technology was acceptable. Because of the recent improvements in block material and computerized numeric control milling machines, the subtractive RP method may be a good choice for dental arch models.

The relationship of dental caries and dental fear in Malaysian adolescents: a latent variable approach

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2014-01-01

Background To investigate the role of geography (place of residence) as a moderator in the relationship between dental caries disease and treatment experience and dental fear in 16-year-olds living in Malaysia. Methods A multi-stage-stratified sampling method was employed. Five hundred and three, 16-year-olds from 6 government secondary schools participated in this study. The questionnaire examined participants’ demographic profile and assessed their dental fear using the Dental Fear Survey (DFS). The clinical examination consisted of the DMFT as the outcome measure of dental caries disease and treatment experience by a single examiner (ICC = 0.98). Structural equation modelling inspected the relationship between dental fear and dental caries disease and treatment experience. Results The mean DMFT was 2.76 (SD 3.25). The DT, MT and FT components were 0.64 (SD 1.25), 0.14 (SD 0.56) and 1.98 (SD 2.43) respectively. Rural compared with urban adolescents had significantly greater mean numbers of decayed and missing teeth. The mean DFS score was 40.8 (SD 12.4). Rural compared with urban adolescents had significantly higher mean scores for physical symptoms of dental fear. The correlation between dental fear (DFS) and dental caries disease and treatment experience (DMFT) was 0.29, p dental caries disease and treatment experience. The strength of the relationship between dental fear and dental caries disease and treatment experience varied in accordance with place of residence. Conclusion In conclusion a relationship between dental fear and dental caries disease and treatment experience was shown to exist in 16-year-old adolescents living in Malaysia. This study showed that the rural–urban dichotomy acted as a moderator upon this relationship. PMID:24621226

Inter-arch digital model vs. manual cast measurements: Accuracy and reliability.

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Kiviahde, Heikki; Bukovac, Lea; Jussila, Päivi; Pesonen, Paula; Sipilä, Kirsi; Raustia, Aune; Pirttiniemi, Pertti

2017-06-28

The purpose of this study was to evaluate the accuracy and reliability of inter-arch measurements using digital dental models and conventional dental casts. Thirty sets of dental casts with permanent dentition were examined. Manual measurements were done with a digital caliper directly on the dental casts, and digital measurements were made on 3D models by two independent examiners. Intra-class correlation coefficients (ICC), a paired sample t-test or Wilcoxon signed-rank test, and Bland-Altman plots were used to evaluate intra- and inter-examiner error and to determine the accuracy and reliability of the measurements. The ICC values were generally good for manual and excellent for digital measurements. The Bland-Altman plots of all the measurements showed good agreement between the manual and digital methods and excellent inter-examiner agreement using the digital method. Inter-arch occlusal measurements on digital models are accurate and reliable and are superior to manual measurements.

Variations in tooth size and arch dimensions in Malay schoolchildren.

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Hussein, Khalid W; Rajion, Zainul A; Hassan, Rozita; Noor, Siti Noor Fazliah Mohd

2009-11-01

To compare the mesio-distal tooth sizes and dental arch dimensions in Malay boys and girls with Class I, Class II and Class III malocclusions. The dental casts of 150 subjects (78 boys, 72 girls), between 12 and 16 years of age, with Class I, Class II and Class III malocclusions were used. Each group consisted of 50 subjects. An electronic digital caliper was used to measure the mesio-distal tooth sizes of the upper and lower permanent teeth (first molar to first molar), the intercanine and intermolar widths. The arch lengths and arch perimeters were measured with AutoCAD software (Autodesk Inc., San Rafael, CA, U.S.A.). The mesio-distal dimensions of the upper lateral incisors and canines in the Class I malocclusion group were significantly smaller than the corresponding teeth in the Class III and Class II groups, respectively. The lower canines and first molars were significantly smaller in the Class I group than the corresponding teeth in the Class II group. The lower intercanine width was significantly smaller in the Class II group as compared with the Class I group, and the upper intermolar width was significantly larger in Class III group as compared with the Class II group. There were no significant differences in the arch perimeters or arch lengths. The boys had significantly wider teeth than the girls, except for the left lower second premolar. The boys also had larger upper and lower intermolar widths and lower intercanine width than the girls. Small, but statistically significant, differences in tooth sizes are not necessarily accompanied by significant arch width, arch length or arch perimeter differences. Generally, boys have wider teeth, larger lower intercanine width and upper and lower intermolar widths than girls.

Simplified zygomatic arch radiographic technique to overcome the drawback of jug handle view

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Siddana Gouda Siddana

2014-01-01

Full Text Available Introduction: The imaging of the zygomatic arch is very important in the diagnosis and management of zygomatic arch fractures. It is accomplished by jug handle radiography (a variation of the submentovertex view and sometimes with modifications like the tangential or tea cup projection. For these techniques, the patient has to be positioned in a way which makes it non-applicable in cases having cervical injuries or suspected cervical injuries. Aims and Objectives: To devise a new approach with which the image of the zygomatic arch can be obtained with normal head position, in either sitting or supine position, using a dental X-ray machine and an occlusal film, which can even be used in patients with cervical injuries or suspected cervical injuries, without any complications. Materials and Methods: The present approach requires a dental X-ray machine and an occlusal X-ray film thereby eliminating the need for additional equipment like a general X-ray machine and extraoral film cassette. This approach can be carried out in a conventional dental setup to rule out zygomatic arch fractures. Conclusion: This technique can be applied in patients having cervical injuries or suspected cervical injuries, thus overcoming the drawback of the jug handle view, and is easy to master. This technique can be used in a conventional dental setup and holds good with the ALARA (as low as reasonably achievable principle of radiation protection and safety.

Knowledge, perceptions and clinical application of the shortened dental arch concept among Malaysian government dentists.

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Kasim, Siti Kamilah Mohd; Razak, Ishak Abdul; Yusof, Zamros Yuzadi Mohd

2018-02-01

To assess the knowledge and perceptions of Malaysian government dentists regarding the shortened dental arch (SDA) concept and its application in clinical practice. The SDA concept refers to a specific type of dentition with intact anterior teeth and a reduction in posterior occlusal pairs. Dentists' knowledge and perceptions of the SDA concept can influence its application in clinical practice. A self-administered questionnaire on the SDA concept was distributed to 326 government dentists in the states of Selangor and Kuala Lumpur, Malaysia. The data were analysed using SPSS version 22 software. The response rate was 84.0%. The majority of respondents had good knowledge on five of six knowledge items and good attitudes towards 10 of 17 perception items. However, only one-fifth (20.4%) reported having applied the SDA concept in the clinic. A larger number of participants who graduated locally than who graduated abroad perceived that patients 5 years of work experience perceived that the SDA concept enables simpler treatment planning (P concept, it is not widely applied in the clinic. Concerted efforts in SDA training of dentists are needed to help to shorten denture waiting lists and reduce costs. © 2017 FDI World Dental Federation.

Footprint parameters as a measure of arch height.

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Hawes, M R; Nachbauer, W; Sovak, D; Nigg, B M

1992-01-01

The human foot has frequently been categorized into arch height groups based upon analysis of footprint parameters. This study investigates the relationship between directly measured arch height and many of the footprint parameters that have been assumed to represent arch height. A total of 115 male subjects were measured and footprint parameters were calculated from digitized outlines. Correlation and regression analyses were used to determine the relationship between footprint measures and arch height. It may be concluded from the results that footprint parameters proposed in the literature (arch angle, footprint index, and arch index) and two further parameters suggested in this study (arch length index and truncated arch index) are invalid as a basis for prediction or categorization of arch height. The categorization of the human foot according to the footprint measures evaluated in this paper represent no more than indices and angles of the plantar surface of the foot itself.

A comparative study on the stress distribution around dental implants in three arch form models for replacing six implants using finite element analysis.

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Zarei, Maryam; Jahangirnezhad, Mahmoud; Yousefimanesh, Hojatollah; Robati, Maryam; Robati, Hossein

2018-01-01

Dental implant is a method to replacement of missing teeth. It is important for replacing the missed anterior teeth. In vitro method is a safe method for evaluation of stress distribution. Finite element analysis as an in vitro method evaluated stress distribution around replacement of six maxillary anterior teeth implants in three models of maxillary arch. In this in vitro study, using ABAQUS software (Simulia Corporation, Vélizy-Villacoublay, France), implant simulation was performed for reconstruction of six maxillary anterior teeth in three models. Two implants were placed on both sides of the canine tooth region (A model); two implants on both sides of the canine tooth region and another on one side of the central incisor region (B model); and two implants on both sides of the canine tooth region and two implants in the central incisor area (C model). All implants evaluated in three arch forms (tapered, ovoid, and square). Data were analyzed by finite analysis software. Von Mises stress by increasing of implant number was reduced. In a comparison of A model in each maxillary arch, the stress created in the cortical and cancellous bones in the square arch was less than ovoid and tapered arches. The stress created in implants and cortical and cancellous bones in C model was less than A and B models. The C model (four-implant) reduced the stress distribution in cortical and cancellous bones, but this pattern must be evaluated according to arch form and cost benefit of patients.

The relationships between the arrangement of teeth, root resorption, and dental maturity in bovine mandibular incisors

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An, Jin-kyu; Ono, Takashi

2017-01-01

Objective The objective of this study is to investigate the eruption pattern and root resorption of the bovine anterior dentition in relation to growth-related parameters based on dental maturity. Methods A cross-sectional study was conducted on 110 bovine anterior mandibles by using standard radiography, cone-beam computed tomography (CBCT), and actual measurements. We determined the relationships between the stages of dental maturity by using a modification of Demirjian's method and various growth-related parameters, such as the activity of the root-resorbing tissue and mobility of the deciduous teeth. The correlation of growth-related parameters with interdental spacing and distal unusual root resorption (DRR) of the deciduous fourth incisor was assessed. The cause of mesial unusual root resorption (MRR) of the deciduous fourth incisor was determined on the basis of the arrangement of the permanent third incisor. Results An independent t-test and chi-square test indicated significant differences in growth-related parameters associated with dental arch length discrepancy and factors related to the shedding of deciduous teeth between the low and high dental maturity groups. The samples with interdental spacing and DRR showed a larger sum of mesiodistal permanent crown widths and higher dental maturity than did the respective controls. Samples with MRR tended to show a lingually rotated distal tip of the adjacent tooth crown. Conclusions Dental maturity has relevance to the interdental spaces and unusual root resorption of mixed dentition. The position of the adjacent tooth crown on CBCT may be correlated with the occurrence of unusual root resorption of the incisor. PMID:29090124

Relationships between dental personnel and non-dental primary health care providers in rural and remote Queensland, Australia: dental perspectives.

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Stuart, Jackie; Hoang, Ha; Crocombe, Len; Barnett, Tony

2017-06-19

Collaboration between dental practitioners and non-dental primary care providers has the potential to improve oral health care for people in rural and remote communities, where access to oral health services is limited. However, there is limited research on collaboration between these professional disciplines. The purpose of this paper was to explore the relationships between dental practitioners and non-dental primary care providers from rural and remote areas of Queensland and to identify strategies that could improve collaboration between these disciplines from the perspective of dental participants. Semi-structured interviews were conducted between 2013 and 2015 with visiting, local and regional dental practitioners (n = 12) who had provided dental services to patients from eight rural and remote Queensland communities that did not have a resident dentist. Participants were purposely recruited through a snow ball sampling technique. Interview data were analysed using thematic analysis with the assistance of QSR Nvivo v.10. Four major themes emerged from the data: (1) Communication between dental practitioners and rural primary care providers; (2) Relationships between dental and primary care providers; (3) Maintenance of professional dualism; (4) Strategies to improve interprofessional relationships (with subthemes: face to face meetings; utilisation of technology; oral health training for primary care providers; and having a community based oral health contact person). Participants observed that there was a lack of communication between the dental providers who saw patients from these rural communities and the primary care providers who worked in each community. This was attributed to poor communication, the high turnover of staff and the siloed behaviours of some practitioners. Visiting dental practitioners were likely to have stronger professional relationships with hospital nursing, administrative and allied health care staff who were often long term

Dental anxiety and personality: investigating the relationship between dental anxiety and self-consciousness.

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Economou, George C

2003-09-01

This study investigated whether personality plays a role in a condition called dental anxiety. Specifically, the study examined the relationship between dental anxiety (the negative response to the stress elicited from a dental interaction) and self-consciousness (the tendency to evaluate aspects of oneself that are subject to private and public display). The purpose of this study was to identify the characteristics possessed by dentally anxious individuals who face potential health risks because of their avoidance. Sixty York University undergraduate students were recruited by convenience sampling to participate. These subjects completed Corah's Dental Anxiety Scale and the Self-Consciousness Scale. The Self-Consciousness Scale consists of three subscales, including private self-consciousness, public self-consciousness, and social anxiety. Results indicated an 0.54 significant correlation between dental anxiety and self-consciousness. The public self-consciousness and social anxiety subscales correlated the most with dental anxiety. Furthermore, the data did not indicate a significant moderating relationship for gender between the two aforementioned variables. These results contribute to the establishment of personality characteristics as one of the dimensions determining dental anxiety.

Is it possible to use cross-sectional and vertical facial measurements to establish the shape of the mandibular arch?

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El Haje, Ossam Abu; Pompeo, Daniela Daufenback; Furtado, Gisela Crippa; Rivera, Luciana Monti Lima; Paranhos, Luiz Renato

2014-11-01

Given the benefits of radiographic cephalometric studies in determining patterns of dental-skeletal-facial normality in orthodontics, the aim of this study was to investigate the association between mandibular dental arch shape and cross-sectional and vertical facial measurements. It was analyzed plaster casts and teleradiographs in frontal and lateral norm belonging to 50 individuals, aged between 15 and 19 years, with no previous history of orthodontic treatment and falling into four of the six Andrews's occlusion keys. The plaster models were scanned (3D) and the images of the dental arches were classified subjectively as oval, triangular and quadrangular by three calibrated examiners, with moderate inter-examiner agreement (Kappa = 0.50). After evaluation of the method error by paired t test (p > 0.05), it was carried out the analysis of cross-sectional and vertical facial measurements to be compared to the shape of the dental arch. Data were subjected to one-way analysis of variance with a significance level of 5%. When the VERT index was compared with the three arch shapes, no measurement showed statistically significant differences (p > 0.05): triangular (0.54); oval (0.43); and quadrangular (0.73); as well as there were no differences (p > 0.05) in the widths of the face (141.20; 141.26; 143.27); maxilla (77.27; 77.57; 78.59) and mandible (105.13; 103.96; 104.28). It can be concluded that there was no correlation between different shapes of the mandibular dental arch and the cross-sectional and vertical facial measurements investigated.

Image Processing Techniques for Assessment of Dental Trays

Science.gov (United States)

2001-10-25

170 patients having Angle Class I molar relationships with minor malocclusions and teeth including second molars fully erupted without loss of tooth...Abstract-A tray selected for the dental patient must adapt to the curvature of the teeth and allow the impression material to be in appropriate...brands of perforated metal trays with 170 lower arch cast models collected from patients having Angle Class 1 type occlusion with minor malocclusions

Dental pulp stone formation during orthodontic treatment: A ...

African Journals Online (AJOL)

2015-06-21

Jun 21, 2015 ... the presence of dental pulp stone, gender, age, tooth type and arches. Results: Dental pulp ... primary and permanent dentition.[1] Dental pulp stones .... interpretation provided training to familiarize the other observer with the ...

Occlusal characteristics and prevalence of associated dental anomalies in the primary dentition.

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Lochib, Seema; Indushekar, K R; Saraf, Bhavna Gupta; Sheoran, Neha; Sardana, Divesh

2015-06-01

Morphological variations in primary dentition are of great concern to a pediatric dentist as it may pose clinical problems like dental caries, delayed exfoliation and also anomalies in the permanent dentition, such as impaction of successors, supernumerary teeth, permanent double teeth or aplasia of teeth. The present study was conducted to investigate the presence of dental anomalies in the primary dentition of 1000 schoolchildren in the 3-5 year-old age group in Faridabad. One-thousand schoolchildren were examined using Type III examination (WHO, 1997) for primary molar relationship, occlusal characteristics, primate spaces, physiological spaces and other anomalies of teeth, including number and morphology. The prevalence of physiological spaces in maxillary and mandibular arches was 50.9% and 46.7%, respectively, whereas primate spaces were found in 61.7% of the children in the maxillary arch and 27.9% in the mandibular arch. The prevalence of unilateral anterior and posterior cross-bite was 0.1% and 0.8%, respectively, in the present study. The prevalence of hypodontia in the primary dentition was found to be 0.4% and the prevalence of fusion and gemination in the present study was 0.5%. Double teeth (fusion and gemination) and hypodontia were the most common dental anomalies found in the primary dentition in the present study. Copyright © 2014 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

A Comparison of Arch Width with Angle Classification and Wits Appraisal in Class 2 Division 1 and Class 1 Individuals.

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1983-05-01

longitudinal changes in arch width between lateral incisors, canines and second premolars or deciduous second molars at four stages of dental eruption in 22 male... dental arch or skeletal widths. Also, he made no attempt to divide his sample into normal and malocclusion groups. -J 7 Warren (1959) studying twenty...buccal crossbite of the posterior teeth Many clinicians believe that this problem is highly correlated with tfte type or classification of malocclusion

ArchE - An Architecture Design Assistant

Science.gov (United States)

2007-08-02

Architecture Design Assistant Len Bass August 2, 2007 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the...ArchE - An Architecture Design Assistant 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...X, Module X 3 Author / Presenter, Date if Needed What is ArchE? ArchE is a software architecture design assistant, which: • Takes quality and

A systematic review of prosthetic restoration in patients with shortened dental arches

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Kenji Fueki

2011-08-01

Full Text Available The literature regarding the effect of prosthetic restoration in patients having distal extension edentulous space in posterior area (shortened dental arch: SDA is reviewed in the following article. Information retrieval followed a systematic approach using PubMed. Articles in English published between 1966 and March 2011 describing the outcome of treatment with various prostheses were evaluated. From the search results of 98 articles, 21 articles met the inclusion criteria. Treatment with removable partial dentures (RPDs improved masticatory function, patient satisfaction and oral health-related quality of life (OHRQoL. However, no significant difference was found in the outcomes between patients with RPDs and with cantilever fixed partial dentures (CFPDs. Caries developed more frequently after treatment with RPDs than CFPDs. The time to survival for CFPDs was not longer than that for RPDs, while more visits to maintain RPDs were required than for CFPDs. No significant difference was found in masticatory function, OHRQoL, and occlusal stability between patients with RPDs and those without restoration of missing molars. Consequently, treatment with RPDs for SDA seems to be less advantageous than CFPDs or no restoration for missing molars. Further research is required to validate treatment with implant-supported fixed partial dentures for SDA.

Comparison of arch forms between Turkish and North American

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Ahmet A. Celebi

2016-04-01

Full Text Available ABSTRACT Objective: The aim of this study was to clarify the morphological differences in the mandibular arches of Turkish and North American white subjects. Methods: The sample included 132 Turkish (34 Class I, 58 Class II, and 40 Class III and 160 North American (60 Class I, 50 Class II, and 50 Class III subjects. The most facial portion of 13 proximal contact areas was digitized from photocopied images of patients' mandibular dental arches. Clinical bracket points were calculated for each tooth based on mandibular tooth thickness data. Four linear and two proportional measurements were taken. The subjects were grouped according to arch form types (tapered, ovoid and square in order to have frequency distribution compared between ethnic groups in each Angle classification. Results: The Turkish group showed significantly lower molar depth and more significant molar width-depth (W/D ratio in all three Angle classifications. On the other hand, the Turkish group also showed a significantly larger intercanine width in Class III malocclusion and intermolar width in Class II malocclusion. The most frequent arch forms seen were the ovoid arch form in the Turkish group and the tapered form in the white group. Conclusions: Our results demonstrate that when treating Turkish patients, one should expect to use preformed ovoid arch form orthodontic wires in a significant percentage of patients.

Effect of aging on the configurational change of the aortic arch

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Atsuhiro Kojima

2016-04-01

Full Text Available We explored the relationship between aging and the configuration of the aortic arch using computed tomography angiography (CTA. We retrospectively reviewed CTA obtained in 140 cases. The configuration of the aortic arch was categorized into three types based on the criteria mentioned by Madhwal et al., and the relationships between each configuration and patient characteristics were analyzed. Anomalies of the aortic arch were also explored. Twenty patients had a type-1 aortic arch (mean age, 56.1 years, 30 patients had a type-2 aortic arch (mean age, 66.3 years, and 89 patients had a type-3 aortic arch (mean age, 71.7 years. The mean age of patients with a type-3 aortic arch was significantly higher than that of patients with a type-1 aortic arch. No significant correlations between the type of aortic arch and other factors, such as smoking habit, were seen. The configuration of the aortic arch in our study appears to be significantly affected by the age of the patients.

Reconstruction of pseudo three-dimensional dental image from dental panoramic radiograph and tooth surface shape

International Nuclear Information System (INIS)

Imura, Masataka; Kuroda, Yoshihiro; Oshiro, Osamu; Kuroda, Tomohiro; Kagiyama, Yoshiyuki; Yagi, Masakazu; Takada, Kenji; Azuma, Hiroko

2010-01-01

Three-dimensional volume data set is useful for diagnosis in dental treatments. However, to obtain three-dimensional images of a dental arch in general dental clinics is difficult. In this paper, we propose a method to reconstruct pseudo three-dimensional dental images from a dental panoramic radiograph and a tooth surface shape which can be obtained from three dimensional shape measurement of a dental impression. The proposed method finds an appropriate curved surface on which the dental panoramic radiograph is mapped by comparing a virtual panoramic image made from a tooth surface shape to a real panoramic radiograph. The developed pseudo three-dimensional dental images give clear impression of patient's dental condition. (author)

Lucy's flat feet: the relationship between the ankle and rearfoot arching in early hominins.

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Jeremy M DeSilva

Full Text Available BACKGROUND: In the Plio-Pleistocene, the hominin foot evolved from a grasping appendage to a stiff, propulsive lever. Central to this transition was the development of the longitudinal arch, a structure that helps store elastic energy and stiffen the foot during bipedal locomotion. Direct evidence for arch evolution, however, has been somewhat elusive given the failure of soft-tissue to fossilize. Paleoanthropologists have relied on footprints and bony correlates of arch development, though little consensus has emerged as to when the arch evolved. METHODOLOGY/PRINCIPAL FINDINGS: Here, we present evidence from radiographs of modern humans (n = 261 that the set of the distal tibia in the sagittal plane, henceforth referred to as the tibial arch angle, is related to rearfoot arching. Non-human primates have a posteriorly directed tibial arch angle, while most humans have an anteriorly directed tibial arch angle. Those humans with a posteriorly directed tibial arch angle (8% have significantly lower talocalcaneal and talar declination angles, both measures of an asymptomatic flatfoot. Application of these results to the hominin fossil record reveals that a well developed rearfoot arch had evolved in Australopithecus afarensis. However, as in humans today, Australopithecus populations exhibited individual variation in foot morphology and arch development, and "Lucy" (A.L. 288-1, a 3.18 Myr-old female Australopithecus, likely possessed asymptomatic flat feet. Additional distal tibiae from the Plio-Pleistocene show variation in tibial arch angles, including two early Homo tibiae that also have slightly posteriorly directed tibial arch angles. CONCLUSIONS/SIGNIFICANCE: This study finds that the rearfoot arch was present in the genus Australopithecus. However, the female Australopithecus afarensis "Lucy" has an ankle morphology consistent with non-pathological flat-footedness. This study suggests that, as in humans today, there was variation in arch

Asymmetry in dentition and shape of pharyngeal arches in the clonal fish Chrosomus eos-neogaeus: Phenotypic plasticity and developmental instability.

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Christelle Leung

Full Text Available The effect of the environment may result in different developmental outcomes. Extrinsic signals can modify developmental pathways and result in alternative phenotypes (phenotypic plasticity. The environment can also be interpreted as a stressor and increase developmental instability (developmental noise. Directional and fluctuating asymmetry provide a conceptual background to discriminate between these results. This study aims at assessing whether variation in dentition and shape of pharyngeal arches of the clonal fish Chrosomus eos-neogaeus results from developmental instability or environmentally induced changes. A total of 262 specimens of the Chrosomus eos-neogaeus complex from 12 natural sites were analysed. X-ray microcomputed tomography (X-ray micro-CT was used to visualize the pharyngeal arches in situ with high resolution. Variation in the number of pharyngeal teeth is high in hybrids in contrast to the relative stability observed in both parental species. The basal dental formula is symmetric while the most frequent alternative dental formula is asymmetric. Within one lineage, large variation in the proportion of individuals bearing basal or alternative dental formulae was observed among sites in the absence of genetic difference. Both dentition and arch shape of this hybrid lineage were explained significantly by environmental differences. Only individuals bearing asymmetric dental formula displayed fluctuating asymmetry as well as directional left-right asymmetry for the arches. The hybrids appeared sensitive to environmental signals and intraspecific variation on pharyngeal teeth was not random but reflects phenotypic plasticity. Altogether, these results support the influence of the environment as a trigger for an alternative developmental pathway resulting in left-right asymmetry in dentition and shape of pharyngeal arches.

Bilateral Maxillary Central Incisor Impaction associated with Developing Supernumerary Premolars in the Mandibular Arch

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Mitali Mishra

2014-01-01

We report a case of 15-year-old girl with bilaterally impacted supernumeraries in the premaxilla region associated with asymptomatic impacted developing supernumerary premolars in the mandibular arch. The supernumeraries of premaxilla region impeded the eruption of the permanent maxillary central incisors. The impacted supernumerary tooth was surgically removed and brackets bonded to the central incisors to apply orthodontic extrusive force which brought the central incisors down to their proper position in the dental arch.

Effects of pre-surgical nasoalveolar moulding on maxillary arch and nasal form in unilateral cleft lip and palate before lip surgery.

Science.gov (United States)

Fuchigami, T; Kimura, N; Kibe, T; Tezuka, M; Amir, M S; Suga, H; Takemoto, Y; Hashiguchi, M; Maeda-Iino, A; Nakamura, N

2017-11-01

To investigate the effects of pre-surgical nasoalveolar moulding (PNAM) on the maxillary arch and nasal form in patients with unilateral cleft lip and palate (UCLP). This is a retrospective case series study. The subjects were infants with complete UCLP who were treated with PNAM (n = 18) at Kagoshima University Medical and Dental Hospital (Japan) between 2006 and 2013. Maxillary dental casts and facial photographs were taken at the time of the first visit and immediately prior to lip surgery to evaluate the maxillary arch and nasal form changes. The dental casts were scanned with a laser scanner, and changes in the 3-Dimensional coordinates of anatomical landmarks and alveolar cleft width were analysed. Moreover, we investigated the correlation between the changes in the maxillary alveolar arch and nasal form. Regarding the maxillary alveolar arch form, the anterior points of the major segment had moved significantly to the cleft side just prior to the time of lip repair, and the alveolar cleft width was significantly decreased. For nasal form, the inclination and displacement of the columella were significantly improved. The improvement of columella inclination was moderately correlated with the posterior movement of the anterior points of the major segment. These findings indicate that PNAM for infants with UCLP enhanced symmetry in the maxillary alveolar arch and nasolabial form. In addition, the posterior movement of the anterior points of the maxillary alveolar arch was correlated with the improvement of columella deformation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mechanical equilibrium of forces and moments applied on orthodontic brackets of a dental arch: Correlation with literature data on two and three adjacent teeth.

Science.gov (United States)

Wagner, Delphine; Bolender, Yves; Rémond, Yves; George, Daniel

2017-01-01

Although orthodontics have greatly improved over the years, understanding of its associated biomechanics remains incomplete and is mainly based on two dimensional (2D) mechanical equilibrium and long-time clinical experience. Little experimental information exists in three dimensions (3D) about the forces and moments developed on orthodontic brackets over more than two or three adjacent teeth. We define here a simplified methodology to quantify 3D forces and moments applied on orthodontic brackets fixed on a dental arch and validate our methodology using existing results from the literature by means of simplified hypotheses.

The relationship between diet and Dental Caries

International Nuclear Information System (INIS)

Duggal, M. S

1991-01-01

Dental caries is a disease of multifactorial etiology and results from a complex interaction between both cariogenic and protective influences acting on the teeth. Though diet plays a major role in the causation of dental caries it has been a common mistake to over-simplify the relationship. Dietary manipulation is also extremely difficult to achieve thus limiting its role in the prevention of caries. Accordingly, alternative preventive measures such as the use of fissure sealants and fluoride which enhance the resistance of the host to disease and are of proven efficacy are more likely to be successful in the control and prevention of dental caries. (author)

Association between breastfeeding duration, non-nutritive sucking habits and dental arch dimensions in deciduous dentition: a cross-sectional study.

Science.gov (United States)

Agarwal, Shiv Shankar; Nehra, Karan; Sharma, Mohit; Jayan, Balakrishna; Poonia, Anish; Bhattal, Hiteshwar

2014-10-31

This cross-sectional retrospective study was conducted to determine association between breastfeeding duration, non-nutritive sucking habits, dental arch transverse diameters, posterior crossbite and anterior open bite in deciduous dentition. 415 children (228 males and 187 females), 4 to 6 years old, from a mixed Indian population were clinically examined. Based on written questionnaire answered by parents, children were divided into two groups: group 1 (breastfed for anterior open bite did not differ significantly between the two groups (P = 0.865). The distribution of posterior crossbite was significantly different between the two groups (P = 0.001). OR assessment (OR = 1.852) revealed that group 1 had almost twofold higher prevalence of NNS habits than group 2. Multivariate logistic regression analysis revealed that the first group had independently fourfold increased risk of developing crossbite compared to the second group (OR = 4.3). Multivariate linear regression analysis also revealed that age and breastfeeding duration were the most significant determinants of ICD and IMD. An increased prevalence of NNS in the first group suggests that NNS is a dominant variable in the association between breastfeeding duration and reduced intra-arch transverse diameters which leads to increased prevalence of posterior crossbites as seen in our study. Mandibular inter-canine width is however unaffected due to a lowered tongue posture seen in these children.

Panoramic dental X-ray machine X-motion drive

International Nuclear Information System (INIS)

Cushman, R.H.; Flynn, J.J.

1980-01-01

A panoramic dental x-ray machine is described which provides continuous and discontinuous radiographic images of the dental arch area of a patient. The systems for moving the chair and the column which carries the x-ray source and camera are specified. (U.K.)

Relationship between the mobility of medial longitudinal arch and postural control

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Tansu Birinci

2017-05-01

Conclusion: Our results suggest that decrease of arch mobility on the dominant foot is associated with posterior sway by causing knee or hip strategy and preventing ankle strategy even in small perturbations. The rate of deviation from the equilibrium point and the degree of total swaying increase when arch mobility decreases.

A study of dentists’ preferences for the restoration of shortened dental arches with partial dentures

Science.gov (United States)

Nassani, Mohammad Zakaria; Ibraheem, Shukran; Al-Hallak, Khaled Rateb; Ali El Khalifa, Mohammed Othman; Baroudi, Kusai

2015-01-01

Objective: This study aimed to use a utility method in order to assess dentists’ preferences for the restoration of shortened dental arches (SDAs) with partial dentures. Also, the impact of patient age and length of the SDA on dentists’ preferences for the partial dentures was investigated. Materials and Methods: Totally, 104 subjects holding a basic degree in dentistry and working as staff members in a private dental college in Saudi Arabia were interviewed and presented with 12 scenarios for patients of different ages and mandibular SDAs of varying length. Participants were asked to indicate on a standardized visual analog scale how they would value the health of the patient's mouth if the mandibular SDAs were restored with cobalt-chromium removable partial dentures (RPDs). Results: With a utility value of 0.0 representing the worst possible health state for a mouth and 1.0 representing the best, dentists’ average utility value of the RPD for the SDAs was 0.49 (sd= 0.15). Mean utility scores of the RPDs across the 12 SDA scenarios ranged between 0.35 and 0.61. RPDs that restored the extremely SDAs attracted the highest utility values and dentists’ utility of the RPD significantly increased with the increase in the number of missing posterior teeth. No significant differences in dentists’ mean utility values for the RPD were identified among SDA scenarios for patients of different ages. Conclusion: Restoration of the mandibular SDAs by RPDs is not a highly preferred treatment option among the surveyed group of dentists. Length of the SDA affects dentists’ preferences for the RPD, but patient age does not. PMID:26038647

Relationship between dental anomalies and orthodontic root resorption of upper incisors

NARCIS (Netherlands)

van Parys, K.; Aartman, I.H.A.; Kuitert, R.; Zentner, A.

2012-01-01

The aim of this study was to examine the potential relationship between the occurrence of orthodontic root resorption and presence of dental anomalies such as tooth agenesis and pipette-shaped roots. Dental anomalies and root resorption were assessed on dental panoramic tomographs (DPT) of 88

A technique to stabilize record bases for Gothic arch tracings in patients with implant-retained complete dentures.

Science.gov (United States)

Raigrodski, A J; Sadan, A; Carruth, P L

1998-12-01

Clinicians have long expressed concern about the accuracy of the Gothic arch tracing for recording centric relation in edentulous patients. With the use of dental implants to assist in retaining complete dentures, the problem of inaccurate recordings, made for patients without natural teeth, can be significantly reduced. This article presents a technique that uses healing abutments to stabilize the record bases so that an accurate Gothic arch tracing can be made.

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....

The relationship between dental caries and dental fluorosis in areas with moderate- and high-fluoride drinking water in Ethiopia.

Science.gov (United States)

Wondwossen, Fantaye; Astrøm, Anne Nordrehaug; Bjorvatn, Kjell; Bårdsen, Asgeir

2004-10-01

The aim of the study is to assess the relationship between caries and dental fluorosis in Ethiopian children living in Rift Valley areas known for endemic fluorosis. A total of 306 children (12-15 years old), selected from areas with moderate (0.3-2.2 mg/l), or high (10-14 mg/l) fluoride concentration in the drinking water were interviewed and examined for caries and dental fluorosis. Scorings were recorded according to the DMF system, and the Thylstrup-Fejerskov (TF) Index. Prevalence of dental fluorosis (TF-score > or = 1) was 91.8% (moderate area) and 100% (high-fluoride area). The corresponding caries prevalence and mean DMFT in the areas were 45.3% versus 61.6%, and 1.2 versus 1.8, respectively. Age and severity of dental fluorosis were found to be independent predictors for DMFT > or = 1. When compared with 12-year olds with TF-scores 0-4, odds ratios were 3.0 (95% CI 1.6-5.7) and 2.0 (95% CI 1.2-3.2) if TF-scores were > or = 5 and age 13-15 years, respectively. A positive relationship between caries and fluorosis was observed across tooth types in both areas. The percentage of children with DMFT > or = 1 was highest in groups with TF-score > or = 5 in the second molar, followed by the first molar. The present findings indicate that the second molar is the tooth most severely affected by dental fluorosis and dental caries. Dental caries increased with increasing severity of dental fluorosis, both in moderate- and high-fluoride areas. Thus, a positive relationship between dental caries and dental fluorosis was observed across various tooth types, in both areas. Copyright Blackwell Munksgaard, 2004

Dental and oral anomalies in incontinentia pigmenti: a systematic review.

Science.gov (United States)

Minić, Snežana; Trpinac, Dušan; Gabriel, Heinz; Gencik, Martin; Obradović, Miljana

2013-01-01

Incontinentia pigmenti (IP) is an X-linked genodermatosis caused by a mutation of the IKBKG gene. The objective of this study was to present a systematic review of the dental and oral types of anomalies, to determine the total number and sex distribution of the anomalies, and to analyze possible therapies. We analyzed the literature data from 1,286 IP cases from the period 1993-2010. Dental and/or oral anomalies were diagnosed for 54.38% of the investigated IP patients. Most of the anomaly types were dental, and the most frequent of these were dental shape anomalies, hypodontia, and delayed dentition. The most frequent oral anomaly types were cleft palate and high arched palate. IKBKG exon 4-10 deletion was present in 86.36% of genetically confirmed IP patients. According to the frequency, dental and/or oral anomalies represent the most frequent and important IP minor criteria. The most frequent mutation was IKBKG exon 4-10 deletion. The majority of dental anomalies and some of the oral anomalies could be corrected. Because of the presence of cleft palate and high arched palate in IP patients, these two anomalies may be considered as diagnostic IP minor criteria as well.

Avaliação longitudinal de arcadas dentárias individualizadas com o método Borda WALA Lontigitudinal evaluation of dental arches individualizated by WALA ridge

Directory of Open Access Journals (Sweden)

Márcia de Fátima Conti

2011-04-01

Full Text Available INTRODUÇÃO: a forma da arcada dentária inferior é considerada uma das principais referências no diagnóstico, sendo um fator importante para a estabilidade do tratamento ortodôntico. OBJETIVOS: avaliar as alterações nas distâncias intercaninos e intermolares inferiores durante e 3 anos após a finalização do tratamento ortodôntico, no qual foi utilizado o método Borda WALA para individualização da forma da arcada dentária. MÉTODOS: a amostra foi composta por 20 pacientes (12 do sexo feminino e 8 do masculino, com idade média de 20,88 anos. Os modelos de gesso iniciais, finais e de pós-tratamento foram utilizados para medição das distâncias intercaninos e intermolares no centro da vestibular da coroa clínica e na largura da Borda WALA. Os dados foram avaliados por meio do teste ANOVA dependente seguido pelo teste de Tukey (pINTRODUCTION: The form of mandibular arch is considered one of the main references among the diagnostic tools because the maintenance of this arch form and dimension is an important factor for stability of orthodontic treatment. OBJECTIVES: To evaluate the changes in mandibular intercanine and intermolar widths during orthodontic treatment and 3 years of posttreatment, in which the WALA ridge was used for individualization of the mandibular arch form. METHODS: Sample comprised of 20 patients (12 women and 8 men, with a mean age of 20.88 years. The dental casts of the initial, final and post-treatment evaluation were used for measurement of the intercanine and intermolar distances in the center of the buccal surface of the clinical crown and in the width of the WALA ridge. Data were analyzed by means of ANOVA test followed by Tukey test (p<0.05. RESULTS: Indicated that there was a statistically significant difference in intercanine and intermolar distances among the three stages evaluated. These distances increased significantly with treatment, and presented a reduction in the post-treatment period

Complete-arch accuracy of intraoral scanners.

Science.gov (United States)

Treesh, Joshua C; Liacouras, Peter C; Taft, Robert M; Brooks, Daniel I; Raiciulescu, Sorana; Ellert, Daniel O; Grant, Gerald T; Ye, Ling

2018-04-30

Intraoral scanners have shown varied results in complete-arch applications. The purpose of this in vitro study was to evaluate the complete-arch accuracy of 4 intraoral scanners based on trueness and precision measurements compared with a known reference (trueness) and with each other (precision). Four intraoral scanners were evaluated: CEREC Bluecam, CEREC Omnicam, TRIOS Color, and Carestream CS 3500. A complete-arch reference cast was created and printed using a 3-dimensional dental cast printer with photopolymer resin. The reference cast was digitized using a laboratory-based white light 3-dimensional scanner. The printed reference cast was scanned 10 times with each intraoral scanner. The digital standard tessellation language (STL) files from each scanner were then registered to the reference file and compared with differences in trueness and precision using a 3-dimensional modeling software. Additionally, scanning time was recorded for each scan performed. The Wilcoxon signed rank, Kruskal-Wallis, and Dunn tests were used to detect differences for trueness, precision, and scanning time (α=.05). Carestream CS 3500 had the lowest overall trueness and precision compared with Bluecam and TRIOS Color. The fourth scanner, Omnicam, had intermediate trueness and precision. All of the scanners tended to underestimate the size of the reference file, with exception of the Carestream CS 3500, which was more variable. Based on visual inspection of the color rendering of signed differences, the greatest amount of error tended to be in the posterior aspects of the arch, with local errors exceeding 100 μm for all scans. The single capture scanner Carestream CS 3500 had the overall longest scan times and was significantly slower than the continuous capture scanners TRIOS Color and Omnicam. Significant differences in both trueness and precision were found among the scanners. Scan times of the continuous capture scanners were faster than the single capture scanners

Arch reconstruction with autologous pulmonary artery patch in interrupted aortic arch.

Science.gov (United States)

Lee, Won-Young; Park, Jeong-Jun

2014-04-01

Various surgical techniques have been developed for the repair of an interrupted aortic arch. However, tension and Gothic arch formation at the anastomotic site have remained major problems for these techniques: Excessive tension causes arch stenosis and left main bronchus compression, and Gothic arch configuration is related to cardiovascular complications. To resolve these problems, we adopted a modified surgical technique of distal aortic arch augmentation using an autologous main pulmonary artery patch. The descending aorta was then anastomosed to the augmented aortic arch in an end-to-side manner. Here, we report two cases of interrupted aortic arch that were repaired using this technique.

Increasing the number of inter-arch contacts improves mastication in adults with Down syndrome: a prospective controlled trial.

Science.gov (United States)

Hennequin, Martine; Mazille, Marie-Noëlle; Cousson, Pierre-Yves; Nicolas, Emmanuel

2015-06-01

Feeding difficulties due to their condition have been widely described for babies, children and adults with Down syndrome (DS). A previous study demonstrated that, compared with wearing a placebo appliance, wearing an occlusal appliance increased inter-arch dental contacts, improved the oral health status of adults with DS and normalised their mandibular rest position. This longitudinal prospective controlled trial aimed to evaluate whether increasing inter-arch contacts in adults with DS would lead to improved masticatory efficiency. Fourteen subjects with DS (mean age±SD: 28.5±9.3years) and twelve controls without DS (24.6±1.0years) were video recorded while chewing samples of carrot and peanuts with and without an oral appliance that was designed to equalise the number of posterior functional units (PFUs) in both groups. Three parameters were collected during mastication for 15cycles and until swallowing: food refusals, food bolus granulometry (D50) and kinematic parameters of the chewing process (number of cycles, chewing duration and cycle frequency within the chewing sequence). In the DS group, increasing the number of PFUs led to a decrease in bolus particle size, to fewer masticatory cycles needed to produce a bolus ready for swallowing and to a decrease in the occurrence of food refusal, while mean chewing frequency did not vary. In the control group, bolus granulometry and chewing time increased with appliance wear while mean chewing frequency decreased. These changes clearly indicate a functional improvement in subjects with DS. This study also demonstrated a causal relationship between the number of functional pairs of posterior teeth and improved mastication. Any evaluation of feeding behaviour in persons with DS should consider inter-arch dental contacts as an explicative variable for feeding problems and their nutritional and respiratory consequences. Copyright © 2015 Elsevier Inc. All rights reserved.

Anterior maxillary segmental distraction for correction of maxillary hypoplasia and dental crowding in cleft palate patients: a preliminary report.

Science.gov (United States)

Wang, X-X; Wang, X; Li, Z-L; Yi, B; Liang, C; Jia, Y-L; Zou, B-S

2009-12-01

To evaluate the feasibility of anterior maxillary segmental distraction (AMSD) to correct maxillary hypoplasia and severe dental crowding in cleft lip and palate (CLP) patients, 7 patients (average age 16.4 years) with maxillary hypoplasia, shortened maxillary dental arch length and severe anterior dental crowding secondary to CLP were selected for this study. After anterior maxillary segmental osteotomy, 3 patients were treated using bilateral internal distraction devices, and 4 patients were treated using rigid external distraction devices. Photographs and radiographs were taken to review the improvement in facial profile and occlusion after distraction. An average 10.25 mm anterior maxillary advancement was obtained in all patients after 10-23 days of distraction and 9-16 weeks of consolidation. The sella-nasion-point A (SNA) angle increased from 69.5 degrees to 79.6 degrees. Midface convexity was greatly improved and velopharyngeal competence was preserved. The maxillary dental arch length was greatly increased by 10.1 mm (P<0.01). Dental crowding and malocclusion were corrected by orthodontic treatment. These results show that AMSD can effectively correct the hypoplastic maxilla and severe dental crowding associated with CLP by increasing the midface convexity and dental arch length while preserving velopharyngeal function, and dental crowding can be corrected without requiring tooth extraction.

The role of polymorphisms associated with early tooth eruption in dental and occlusal traits in East Asian populations

Science.gov (United States)

Kawaguchi, Akira; Kim, Yong-Il; Haga, Shugo; Katayama, Koshu; Ishida, Hajime; Park, Soo-Byung; Maki, Koutaro; Kimura, Ryosuke

2014-01-01

Objective A recent study suggested that rs6504340, a polymorphism within the homeobox B (HOXB) gene cluster, is associated with the susceptibility for malocclusions in Europeans. The resulting malocclusions require orthodontic treatment. The aim of this study was to investigate the association of rs6504340 and other dentition-implicated polymorphisms with dental and occlusal traits in Korean and Japanese populations. Methods The study participants included 223 unrelated Koreans from the Busan area and 256 unrelated Japanese individuals from the Tokyo metropolitan area. DNA samples were extracted from saliva specimens. Genotyping for rs6504340 and four single nucleotide polymorphisms (SNPs) that have been shown to be associated with the timing of first tooth eruption and the number of teeth at 1 year of age (rs10506525, rs1956529, rs9674544, and rs8079702) was performed using TaqMan assays. The Index of Orthodontic Treatment Need (IOTN), overjet, overbite, arch length discrepancy, crown sizes, and length and width of the dental arches were measured. Spearman's correlation coefficients were calculated to evaluate relationships between rs6504340 and these dental/occlusal traits. Results We evaluated the aesthetic components and dental health components of the IOTN in the Korean and Japanese populations and found that neither rs6504340 nor the other four SNPs showed any association with dental and occlusal traits in these East Asian populations. Conclusions These negative results suggest that further research is needed to identify the genetic determinants of malocclusions in order to reach a consensus. PMID:24696826

Crozat appliance therapy for an arch-length discrepancy problem.

Science.gov (United States)

Parker, M

1991-01-01

The case involved a white male subject, aged 10 years 6 months, with a Class I molar relationship complicated by a deep overbite and impaction of all four permanent canines, which were completely blocked out of the arches. The growth rate of the arches was found to be abnormal, and there was premature loss of the deciduous teeth. Over a period of approximately 5 years, with intermittent pauses to allow growth to catch up with treatment, the Crozat removable appliance was used to help establish the arch form and correct the plane of occlusion.

The nance lingual arch: an auxiliary device in solving lower anterior crowding.

Science.gov (United States)

Almeida, Renato Rodrigues de; Oltramari-Navarro, Paula Vanessa Pedron; Almeida, Marcio Rodrigues de; Conti, Ana Cláudia de Castro Ferreira; Navarro, Ricardo de Lima; Pacenko, Murilo Rizental

2011-01-01

After exfoliation of the primary incisors and eruption of the permanent incisors, the dentist has the opportunity of observing closely the beginning of occlusal changes. In several cases, alterations, such as lower anterior crowding, can be prevented and treated with proper follow-up. In the mixed dentition, one of the mechanisms for maintaining space and favoring dental alignment is to preserve leeway space before permanent second molar irruption. Among the devices with this function, the Nance lingual arch helps maintaining the position of the permanent mandibular molars and incisors after a premature loss of the primary canines. This paper describes the applicability of Nance lingual arch for preserving leeway space, thus contributing for correction of lower anterior crowding.

In vivo precision of conventional and digital methods of obtaining complete-arch dental impressions

OpenAIRE

Ender, Andreas; Attin, Thomas; Mehl, Albert

2016-01-01

STATEMENT OF PROBLEM: Digital impression systems have undergone significant development in recent years, but few studies have investigated the accuracy of the technique in vivo, particularly compared with conventional impression techniques. PURPOSE: The purpose of this in vivo study was to investigate the precision of conventional and digital methods for complete-arch impressions. MATERIAL AND METHODS: Complete-arch impressions were obtained using 5 conventional (polyether, POE; vinylsilox...

Integration of digital dental casts in cone-beam computed tomography scans

NARCIS (Netherlands)

Rangel, F.A.; Maal, T.J.J.; Berge, S.J.; Kuijpers-Jagtman, A.M.

2012-01-01

Cone-beam computed tomography (CBCT) is widely used in maxillofacial surgery. The CBCT image of the dental arches, however, is of insufficient quality to use in digital planning of orthognathic surgery. Several authors have described methods to integrate digital dental casts into CBCT scans, but all

Relationship between dental anomalies and orthodontic root resorption of upper incisors.

Science.gov (United States)

Van Parys, Katrien; Aartman, Irene H A; Kuitert, Reinder; Zentner, Andrej

2012-10-01

The aim of this study was to examine the potential relationship between the occurrence of orthodontic root resorption and presence of dental anomalies such as tooth agenesis and pipette-shaped roots. Dental anomalies and root resorption were assessed on dental panoramic tomographs (DPT) of 88 subjects, 27 males and 61 females, mean age 28.4 (SD = 11.3 years), selected from orthodontic patients on the basis of the following exclusion criteria: previous fixed appliance treatment, bad quality of the DPTs and no visibility of the periodontal ligament of every tooth, and younger than 15 years of age at the onset of treatment with fixed edgewise appliance lasting at least 18 months. A pipette-shaped root was identified as defined by a drawing. Tooth agenesis was assessed on DPTs and from subjects' dental history. Root resorption was calculated as the difference between the root length before and after treatment, with and without a correction factor (crown length post-treatment/crown length pre-treatment). If one of the four upper incisors showed root resorption of ≥2.3 mm with both formulas, the patient was scored as having root resorption. Chi-square tests indicated that there was no relationship between orthodontic root resorption and agenesis (P = 0.885) nor between orthodontic root resorption and pipette-shaped roots (P = 0.800). There was no relationship between having one of the anomalies and root resorption either (P = 0.750). In the present study, it was not possible to confirm on DPTs a relationship between orthodontic root resorption and dental anomalies, such as agenesis and pipette-shaped roots.

Comparative analysis of 3D data accuracy of single tooth and full dental arch captured by different intraoral and laboratory digital impression systems.

Science.gov (United States)

Ryakhovskiy, A N; Kostyukova, V V

2016-01-01

The aim of this study was to compare the accuracy of digital impressions taken by different intraoral and laboratory scanners. For this purpose a synthetic jaw model with prepared tooth was scanned using intraoral scanning systems: 3D Progress (MHT S.P.A., IT - MHT Optic Research AG, CH); True Definition (3M ESPE, USA); Trios (3Shape A/S, DNK); CEREC AC Bluecam, CEREC Omnicam (Sirona Dental System GmbH, DE); Planscan (Planmeca, FIN); and laboratory scanning systems: s600 ARTI (Zirkonzahn GmbH, IT); Imetric Iscan D104, CH); D900 (3Shape A/S, DNK); Zfx Evolution (Zfx GmbH, DE) (each n=10). Reference-scanning was done by ATOS Core (GOM mbH, DE). The resulting digital impressions were superimposed with the master-scan. The measured deviations by points (trueness) for intraoral scanners were: True Definition - 15.0±2.85 μm (single tooth) and 45.0±19.11 µm (full arch); Trios - 17.1±1.44 and 58.8±27.36 µm; CEREC AC Bluecam - 22.3±5.58 and 20.3±4.13 µm; CEREC Omnicam - 25.0±1.06 and 78.5±27.03 µm; 3D Progress - 26.4±5.75 and 213.5±47.44 µm; Planscan - 54.6±11.58 and 205.2±21.73 µm. For laboratory scanners: Imetric Iscan D104 - 10.2±0.87 μm (stamp) and 65.3±5.36 µm (full arch); Zfx Evolution - 12.8±0.83 and 66.4±2.80 µm; Zirkonzahn s600 ARTI - 15.1±1.36 and 65.9±1.33 µm; 3Shape D900 - 19.9±0.53 and 63.6±0.83 µm. Precision was: True Definition - 19.9±2.77 μm (single tooth) and 40.1±11.04 µm (full arch); Trios - 25.8±2.49 and 69.9±18.95 µm; CEREC AC Bluecam - 36.4±2.78 and 46.6±3.44 µm; CEREC Omnicam - 37.6±3.29 and 76.2±13.36 µm; 3D Progress - 76.9±11.04 and 102.2±8.06 µm; Planscan - 74.3±6.58 and 93.9±15.32 µm. For laboratory scanners: Imetric Iscan D104 - 11.7±4.39 μm (stamp) and 31.2±5.58 µm (full arch); Zfx Evolution - 8.4±0.49 and 24.8±3.98 µm; Zirkonzahn s600 ARTI - 13.4±6.74 and 20.7±4.34 µm; 3Shape D900 - 10.4±0.93 and 17.8±0.62 µm. Whole deviation of the dental arch was: 3D Progress - 98.0±5.70 µm

Relationship between needle phobia and dental anxiety

NARCIS (Netherlands)

Majstorovic, M.; Veerkamp, J.S.J.

2004-01-01

Purpose: This cross-sectional study aimed to explain the nature of needle phobia and its relationship in dental phobic children with evidence on age-related differences. Methods: The study used 2,865 patients (52% boys, 48% girls), 4 to 11 years old (mean=7.18 years). The patient sample included

Rearfoot eversion has indirect effects on plantar fascia tension by changing the amount of arch collapse.

Science.gov (United States)

Lee, Sae Yong; Hertel, Jay; Lee, Sung Cheol

2010-01-01

Rearfoot eversion motion and arch height are believed to contribute to increased tension on the plantar fascia and arch collapse during gait but the specifics of these relationships are not clear. To examine the relationships among static arch height, rearfoot eversion, dynamic arch height, and plantar fascia tension. 28 healthy males participated. After static arch height was measured, the subjects were asked to run at 4.5m/s while frontal plane rearfoot motion, dynamic arch height, and ground reaction forces were collected. The relationships among variables were examined with bivariate correlations and path analysis. The results indicated a high correlation between dynamic arch height and static arch height (r=0.642), plantar fascia tension (r=-0.797), and maximum rearfoot eversion motion during gait (r=-0.518). The path analysis model without the direct rearfoot eversion effect explained 81.2% of the variance in plantar fascia tension, while the model with the direct rearfoot eversion effect explained 82.1% of the variance in plantar fascia tension. Including the indirect effect of maximum rearfoot eversion motion on plantar fascia tension through control of dynamic arch height is the model that best explains the interrelationships of these foot characteristics. The amount of maximum rearfoot eversion motion itself is not a good predictor of plantar fascia tension, however, together with the arch height, maximum rearfoot eversion motion is a good predictor because it has a pronounced indirect effect on plantar fascia tension. Copyright 2010. Published by Elsevier Ltd.

Thin-plate spline analysis of arch form in a Southern European population with an ideal natural occlusion.

Science.gov (United States)

Camporesi, Matteo; Franchi, Lorenzo; Baccetti, Tiziano; Antonini, Antonino

2006-04-01

The purpose of the present study was to identify the mean configuration of the clinical arch form in a sample of Southern European subjects with ideal natural occlusion by means of Procrustes analysis, and to compare the identified configuration with 10 commercially produced arch forms by means of thin-plate spline (TPS) analysis. The sample comprised the study casts of 50 subjects (26 males and 24 females). The mean age of the sample was 26 years +/- 4 years. All subjects were young Caucasian adults of Southern European ancestry, and presented with an ideal natural occlusion. The three-dimensional (3D) co-ordinates of all dental points (facial axis points) were digitized using a 3D electromagnetic digitizer. The morphometric technique of TPS analysis with permutation tests was used to compare the configurations of landmarks in the various specimens. No sexual dimorphism was found for either upper or lower arch forms when the shape of the arches was assessed independently from size. The commercially available arch form that showed the least, though statistically significant, shape difference with respect to the average calculated configuration was the Brader arch form.

Adult Dental Health Survey 2009: relationships between dental attendance patterns, oral health behaviour and the current barriers to dental care.

Science.gov (United States)

Hill, K B; Chadwick, B; Freeman, R; O'Sullivan, I; Murray, J J

2013-01-01

The importance of understanding barriers to dental attendance of adults in the UK was acknowledged in the first Adult Dental Health Survey in 1968 and has been investigated in all subsequent ADH surveys. In 1968, approximately 40% of dentate adults said they attended for a regular check-up; by 2009 this was 61%. Attendance patterns were associated with greater frequency of toothbrushing, use of additional dental hygiene products, lower plaque and calculus levels. Just under three-fifths of adults said they had tried to make an NHS dental appointment in the previous five years. The vast majority (92%) successfully received and attended an appointment, while a further 1% received an appointment but did not attend. The remaining 7% of adults were unable to make an appointment with an NHS dentist. The majority of adults were positive about their last visit to the dentist, with 80% of adults giving no negative feedback about their last dentist visit. Cost and anxiety were important barriers to care. Twenty-six percent of adults said the type of treatment they had opted for in the past had been affected by the cost and 19% said they had delayed dental treatment for the same reason. The 2009 survey data demonstrated a relationship between dental anxiety and dental attendance. Adults with extreme dental anxiety were more likely to attend only when they had trouble with their teeth (22%) than for a regular check-up.

Relationship Between Dental Hygiene Students' Performance in an Oral Radiology Course and the National Board Dental Hygiene Examination: A Retrospective Study.

Science.gov (United States)

Liang, Hui; DeWald, Janice P; Solomon, Eric S

2018-02-01

Dental hygiene students' performance in oral radiology courses may give an early indication of their readiness prior to taking the National Board Dental Hygiene Examination (NBDHE). The aim of this study was to determine the relationship between dental hygiene students' performance in an oral radiology lecture course and their performance on the NBDHE. Data were collected for all 117 dental hygiene students at Texas A&M University College of Dentistry from 2006 to 2009 who took the NBDHE during their second year of the program. Their final grades and scores on three written section examinations in an oral radiology course taken in their first year were compared with their overall NBDHE scores and raw scores on the oral radiology and case study sections. Moderate correlations (0.3radiology course, with the strongest correlation with the final grade (r=0.488, pradiology, followed by scores in anatomic sciences; the weakest relationship was with scores in pharmacology. This relationship can help identify students who may need extra support in the oral radiology course and other courses to prepare them to succeed when they take the NBDHE. This study also contributes to understanding of the general relationship between dental hygiene program courses and students' success on the clinical licensing exam and will hopefully encourage other programs to assess their students' performance in this way.

Arch index and running biomechanics in children aged 10-14 years.

Science.gov (United States)

Hollander, Karsten; Stebbins, Julie; Albertsen, Inke Marie; Hamacher, Daniel; Babin, Kornelia; Hacke, Claudia; Zech, Astrid

2018-03-01

While altered foot arch characteristics (high or low) are frequently assumed to influence lower limb biomechanics and are suspected to be a contributing factor for injuries, the association between arch characteristics and lower limb running biomechanics in children is unclear. Therefore, the aim of this study was to investigate the relationship between a dynamically measured arch index and running biomechanics in healthy children. One hundred and one children aged 10-14 years were included in this study and underwent a biomechanical investigation. Plantar distribution (Novel, Emed) was used to determine the dynamic arch index and 3D motion capture (Vicon) to measure running biomechanics. Linear mixed models were established to determine the association between dynamic arch index and foot strike patterns, running kinematics, kinetics and temporal-spatial outcomes. No association was found between dynamic arch index and rate of rearfoot strikes (p = 0.072). Of all secondary outcomes, only the foot progression angle was associated with the dynamic arch index (p = 0.032) with greater external rotation in lower arched children. Overall, we found only few associations between arch characteristics and running biomechanics in children. However, altered foot arch characteristics are of clinical interest. Future studies should focus on detailed foot biomechanics and include clinically diagnosed high and low arched children. Copyright © 2018 Elsevier B.V. All rights reserved.

The Relationship Between Dietary Factors and Dental Caries.

Science.gov (United States)

Watson, M. Lisa

1982-01-01

The relationship between the development of tooth decay and the diet includes a multitude of variables other than sugar. However, the frequency with which food is consumed and its consistency or stickiness may be primary contributors to the development of dental caries. (JN)

Effect of Polyvinyl Siloxane Viscosity on Accuracy of Dental Implant Impressions

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Ahmad Ghahremanloo

2017-02-01

Full Text Available Objectives: The aim of this study was to compare the accuracy of dental implant impressions obtained by a combination of different impression techniques and viscosities of polyvinyl siloxane (PVS.Materials and Methods: Four parallel fixtures were placed between mental foramina in a master model of lower dental arch. Three different viscosities (putty/light body, medium body/light body, and monophase: heavy body and direct and indirect techniques (six groups were used, and seven impressions were obtained from each group (n=42. To measure the accuracy of impressions, drift, horizontal, and vertical angles of the implants, as well as the hex rotation of the implants in casts were evaluated using a digitizer device (1μm accuracy, in comparison with master arch. Data were analyzed using five-factor two-way ANOVA and Tukey’s post-hoc test.Results: The accuracy of impressions was assessed and the results showed that direct technique was not significantly different from indirect technique (P>0.05. Also, there were no significant differences between the mentioned viscosities except for the horizontal angle (P=0.006.Conclusions: Viscosity of impression materials is of high significance for the accuracy of dental impressions.Keywords: Dental Materials; Dental Implants; Dental Impression Technique; Viscosity; Vinyl Polysiloxane; Dimensional Measurement Accuracy

Correlation between the distance of maxillary central incisors and incisive papilla in different arch form

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Nur Ateyya Natasha Mohd Zali

2018-01-01

Full Text Available In edentulous treatment, relocation of anterior teeth in the preexisting natural position is the utmost importance. It is necessary to refer to the significant anatomical landmarks, one of them is incisive papilla. To make it more efficient both functionally and biologically, the teeth were arranged in particular geometric manner known as a dental arch. The author has chosen to conducted the research among the Malay race represented by the Malay undergraduate students. The purpose of this study was to evaluate the correlation between the distance of maxillary central incisors and incisive papilla (CI-IP in different arch form and gender. Maxillary impressions of 34 dentate individuals were taken, and the measurements were performed using a digital caliper. The results showed the CI-IP distance was ranging between 7.65 to 9.90 mm, with the average of 8.77 mm. There was no significant difference of the CI-IP distance between male and female regardless of their arch forms (p>0.05. Individuals with ovoid and tapered arch form, however, showed a significant difference of the CI-IP distance between male and female (p0.05. It can be concluded that gender factor was irrelevant towards the CI-IP distance regardless of the individual arch form. However, there was a correlation between the CI-IP distance in different arch forms in both male and female sample.

Modified protrusion arch for anterior crossbite correction - a case report.

Science.gov (United States)

Roy, Abhishek Singha; Singh, Gulshan Kr; Tandon, Pradeep; Chaudhary, Ramsukh

2013-01-01

Borderline and mild skeletal Class III relationships in adult patients are usually treated by orthodontic camouflage. Reasonably rood results have been achieved with nonsurgical teatment of anterior crossbite. Class III malocclusion may be associated with mandibular prognathism, maxillary retrognathism, or both. Class III maxillary retrognathism generally involves anterior crossbite, which must be opened if upper labial brackets are to be bonded. If multiple teeth are in crossbite, after opening the bite usual step is to ligate forward or advancement arch made of 0.018" or 0.020" stainless steel or NiTi wire main arch that must be kept separated 2 mm from the slot ofupper incisor braces. Two stops or omegas are made 1 mm mesial to the tubes of the molar bands that will impede main arch from slipping,and in this manner the arch will push the anterior teeth forward Here we have fabricated a modified multiple loop protrusion arch to correct an anterior crossbite with severe crowding that was not amenable to correct by advancement arches.

The relationship between the quality of education and the poor dental practice: Clinical case report

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Cléa Adas Saliba Garbin

2013-01-01

Full Text Available The activities developed in health area are of great importance, because they have the aim to preserve the life of the men, and therefore, must be performed by authorized persons. The increase of the number of dental schools, the decline at the education quality and a higher admission of students with low ability to exercise their profession, are facts that bring disastrous consequences for society. These facts are, also, reflected at the moral, ethical and technical-scientific performance of the professional. The purpose of this clinic case is to show that although there is a significant suplly of education institutions, there is a lack of scientific and adequate technical knowledgement from the graduated dentals surgeons. The patient MSL, 17 year old, female, went to a dental clinic presenting a tray type Vernis, attached to the lower arch. After clinical evaluation, it was showed that an incorrect material was used for the impression technique, being impossible to take out the tray by the conventional mann r. The planning for the removal of the tray was through the divide of it. Thus, the consequence of the lack of knowledge in the use of impression materials had caused a great incovinience to the patient. It can be concluded that the rate of malpractice is directly related to the professional preparation, highlighting the importance of quality dental education for a responsible clinical practice.

Differences in the Microbial Colonization Among Arch Wire Types, Gauges and Cross Sections

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Reem A. Rafeeq

2018-02-01

Full Text Available Background: The presence of orthodontic materials in the oral cavity represent a unique surface that can interact with bacteria, leading to pathogenic plaque formation and subsequent enamel demineralization, Streptococcus mutans play an important role in the initiation and progression of dental caries and they are considered the primary cause of bacteriological caries. The objective of this study was to investigate the effect of multiple factors including the type of arch wire, salivary coating, cross section, and wire thickness on the levels of mutans streptococci adherence. Materials and Methods: Two types of arch wire stainless steel and nickel titanium were selected using the following criteria: round and rectangular with gauges 0.014, 0.018, 0.016 × 0.022 and 0.019 × 0.0 25 inches which were subdivided into eight groups. Bacterial adhesion was quantified by a microbial culture technique and the number of adhesive bacteria were analyzed and counted after growth in culture for each group with and without saliva coating at 15 and 60 minutes. Detection of mutans streptococci by saliva-check Mutans test. Results: There was a significant difference between arch wire types in each time interval and the highest bacterial adhesion on the NiTi arch wires with rectangular cross section in the absence of saliva with extended incubation time. Conclusions: The adherence of mutans streptococci in saliva coated wires seems to be low. At increased incubation time, rectangular cross section arch wire showed an increased number of adhering bacteria with less effect on different gauges of the arch wire.

Establishing a good dentist-patient relationship: skills defined from the dental faculty perspective.

Science.gov (United States)

Orsini, Cesar A; Jerez, Oscar M

2014-10-01

The importance of developing good dentist-patient relationships has been well documented, but previous studies have focused on social techniques, not considering the psychological and behavioral characteristics of patients, and have used definitions and instruments that were not dental-specific. Therefore, the aims of this study were to propose a definition of dentist-patient relationship skills, derived from dental faculty members' criteria and informed by Emotional Intelligence concepts, and to propose a preliminary dental-specific, face-valid, and reliable self-assessment instrument. The study was conducted in three phases. Phases I and II defined dentist-patient relationship competence through literature analysis and semi-structured interviews with expert key informants, establishing the outcome skills. In Phase III, the instrument was constructed and piloted. Communication skills and basic psychological tools resulted in core topics for use in practice. The definition both specifies and broadens social interactions in dentistry by including dental faculty members' criteria and topics such as psychological tools and pre-, intra-, and postoperative topics appropriate for use during consultation, examination, and treatment. The instrument was found suitable, reasonable, and accessible with a Cronbach's alpha level of 0.95. Future studies are needed to confirm the definition, as well as the instrument's validity, reliability, transference, and sensitivity to the dental educational environment.

Integration of Digital Dental Casts in Cone-Beam Computed Tomography Scans

OpenAIRE

Rangel, Frits A.; Maal, Thomas J. J.; Bergé, Stefaan J.; Kuijpers-Jagtman, Anne Marie

2012-01-01

Cone-beam computed tomography (CBCT) is widely used in maxillofacial surgery. The CBCT image of the dental arches, however, is of insufficient quality to use in digital planning of orthognathic surgery. Several authors have described methods to integrate digital dental casts into CBCT scans, but all reported methods have drawbacks. The aim of this feasibility study is to present a new simplified method to integrate digital dental casts into CBCT scans. In a patient scheduled for orthognathic ...

Estudo do relacionamento ântero-posterior entre os arcos dentários decíduos, de crianças nipo-brasileiras, dos dois aos seis anos de idade Study of the anteroposterior relationship between deciduous dental arches of Japanese-Brazilian children, from 2 to 6 years of age

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Dirce Yamada Kataoka

2006-10-01

Full Text Available OBJETIVO: verificar as prevalências dos diferentes tipos de relacionamentos ântero-posteriores entre os arcos dentários decíduos, bem como o possível dimorfismo sexual, em crianças nipo-brasileiras na faixa etária dos dois aos seis anos de idade. METODOLOGIA: foram avaliadas por inspeção visual 310 crianças nipo-brasileiras, matriculadas em 19 escolas do estado de São Paulo, sendo 154 do gênero masculino e 156 do feminino. Os resultados foram submetidos ao teste do qui-quadrado e revelaram ausência de dimorfismo sexual para a maioria dos relacionamentos analisados, permitindo apresentar os resultados conjuntamente para ambos os gêneros. RESULTADOS: as prevalências dos relacionamentos entre os segundos molares decíduos foram: 47,4% para o degrau mesial, 41,3% para o plano terminal reto, 5,5% para o degrau distal e 5,8% para os casos com assimetrias. Para os relacionamentos entre os caninos decíduos, conforme Foster e Hamilton, constataram-se prevalências de 77,4% para a Classe 1, 6,8% para a Classe 2, 6,8% para a Classe 3 e 9% para as relações assimétricas. Apenas a Classe 2 apresentou dimorfismo sexual, sendo de 3,9% para o feminino e de 9,7% para o masculino. Quanto à sobressaliência verificaram-se prevalências de 71,3% para a normal, 14,2% para a aumentada, 7,4% para a mordida cruzada anterior e 7,1% para a mordida topo-a-topo. RESULTADOS: concluiu-se que a maioria das crianças nipo-brasileiras avaliadas neste estudo, apresentaram um relacionamento ântero-posterior normal entre os arcos decíduos, merecendo atenção uma ligeira tendência para o desenvolvimento da Classe 3.AIM: the purpose of this cross-sectional study was to verify the prevalences of different types of anteroposterior relationships between deciduous dental arches and its possible sexual dimorphism, in Japanese-Brazilian children from 2 to 6 years of age. METHODS: a total of 310 Japanese-Brazilian children from 19 schools in São Paulo, Brazil

Effects of early and late cheiloplasty on anterior part of maxillary dental arch development in infants with unilateral complete cleft lip and palate

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Silvia Valentová-Strenáčiková

2016-02-01

Full Text Available Objectives. The objective of this study is to compare the impact of early and late reconstruction of complete unilateral cleft lip and palate on the growth and development of the front of the dentoalveolar arch. Methods. This study was carried out in the years 2012–2015 at the Clinic of Plastic, Reconstructive and Aesthetic Surgery in Banska Bystrica. Infants with unilateral complete cleft lip and palate were divided into 2 groups according to the timing of lip reconstruction. Group A consisted of infants with early lip reconstruction–realised in the first 14 days of life. Group B consisted of infants with later lip reconstruction–realised in the third month of age. Maxillary dental casts were obtained for each child in four periods–in the first 14 days of life, in the third month, in the sixth month and in the age of one year. These were followed by the identification, measurement and evaluation of anthropometric parameters. Results. Significant differences were occurred after the reconstruction of the lips in linear and angle measurements between infants in the A and B groups. Conclusion. The early surgical reconstruction of the lips in the first 14 days of life has a positive effect on the growth and development of the anterior segment of the dentoalveolar arch. Early lip reconstruction forms a continuous pressure on the frontal segment, resulting in the earlier remedy of anatomical properties and creates appropriate conditions for the best development of this area.

Evolution Characteristic Analysis of Pressure-arch of a Double-arch Tunnel in Water-rich Strata

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C. L. Li

2016-03-01

Full Text Available It is of importance to analyze the morphological characterization, the evolution process and the skewed effect of pressure-arch of a double-arch tunnel in the water-rich strata. Taking a buried depth 80 m double-arch tunnel as an example, a computational model of the double-arch tunnel was built by using FLAC3D technique. Then considering some aspects including groundwater conditions, tunnel depth, construction sequences and permeability coefficients, the coupling effect of stress field and seepage field in the pressure-arch of the double-arch tunnel was analyzed. The results show that the thickness of the pressure-arch induced by step-by-step excavation and display a step-descent skewed distribution from the left to the right of the double-arch tunnel. The permeability coefficient has a significant influence on the shape and the skewed effect of the pressure arch. The excavation of the bench method has a better arching condition than that of the expanding method. The abtained results provide a basic reference for the rock reinforcement design and safety construction of double-arch tunnels in the water-rich strata.

Radiographic signs and diagnosis of dental disease

International Nuclear Information System (INIS)

Bellows, J.

1993-01-01

Dental radiographs are critical for the complete assessment and treatment of dental diseases. Dental radiography is commonly used to evaluate congenital dental defects, periodontal disease, orthodontic manipulations, oral tumors, endodontic treatments, oral trauma, and any situation where an abnormality is suspected. Although standard radiographic equipment and film can be used to produce dental radiographs, dental X-ray equipment and film provide superior quality images and greater convenience of animal patient positioning. An understanding of normal dental radiographic anatomy is important when interpreting dental radiographs. Stage III periodontitis is the earliest stage of periodontal disease at which radiographic abnormalities become apparent. Bone loss associated with periodontal disease can be classified as either horizontal or vertical. Periapical radiolucencies can represent granulomas, cysts, or abscesses, whereas periapical radiodensities may represent sclerotic bone or condensing osteitis. Lytic lesions of the bone of the jaw often represent oral neoplasms. Neoplasms also can displace or disrupt teeth in the dental arch. Resorptive lesions can be external or internal and appear as radiolucent areas involving the external surface of the root or the pulp cavity, respectively. Feline dental resorptive lesions, also known as odontoclastic resorptions, are a specific form of dental resorptive lesions unique to cats

Dynamic stability analysis of circular arch subjected to follower forces with small disturbances; Judo kaju wo ukeru enkei arch no yuran ni yoru doteki kyodo to anteisei kaiseki

Energy Technology Data Exchange (ETDEWEB)

Fukuchi, N.; Okada, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Hirano, Y. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

1997-09-04

This paper describes the deformation and dynamic stability of circular arch subjected to follower forces in a submerged membrane type marine structure reinforced by arch frames. Governing equations for finite deformations of the circular arch subjected to follower forces are introduced using an embedded curve coordinate, which are formulated by applying Galerkin method. In addition, equations of motion due to small disturbances under given condition of loading are introduced. Based on these equations, dynamic stability of the arch is analyzed by means of Runnge-Kutta-Gill method, to clarify the relationship between disturbances and instability regions and the resulting phenomena. Near the boundary regions of stability, both amplitude and cycle of deformation are greatly affected by the amplitude of disturbances. The dynamic instability is governed by the inverse symmetry primary mode with minimum characteristic frequency which is specific for the circular arch. The dynamic stability has high parameter dependency, and the instability regions have a complicated shapes. Although flattened arch has a smaller static critical load, it provides the dynamic stability against the disturbance. 5 refs., 10 figs.

Articulated dental cast analysis of asymptomatic and symptomatic populations

Science.gov (United States)

Cordray, Frank E

2016-01-01

Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement (DAD), especially laterally, with symptoms, mandibular condyle displacement (CD) resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache (CMCH) and temporo-mandibular dysfunction (TMD). The objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position (SCP) and the intercuspal position (ICP) and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. The initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. The data revealed significant displacement between the SCP and ICP of the condyles (displaced most frequently inferior (down) and posterior (distal)) and substantially increased frequency and magnitude of displacement of the dental arches (with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes) in symptomatic subjects. These discrepancies were statistically significant and clinically significant. The data support the concept of increased DAD and CD with dysfunction. Transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and TMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint. PMID:27357324

Comparison of Total Arch and Partial Arch Transposition During Hybrid Endovascular Repair for Aortic Arch Disease.

Science.gov (United States)

Kang, W C; Ko, Y-G; Oh, P C; Shin, E K; Park, C-H; Choi, D; Youn, Y N; Lee, D Y

2016-08-01

Total arch transposition (TAT) during hybrid endovascular repair for aortic arch disease is believed to allow a better landing zone, but also to be associated with higher peri-operative mortality than partial arch transposition (PAT). Information on this issue is limited. This study was a retrospective analysis. All 53 consecutive patients with aortic arch disease (41 males, mean age 65.0 years) who underwent hybrid endovascular repair with TAT (zone 0, n=20) or PAT (zone 1 or 2, n=33) from 2008 to 2014 were analyzed retrospectively. The peri-operative and late outcomes of these two groups were compared. Baseline characteristics, including EuroSCORE II results, were similar in the two groups. After procedures, peri-operative mortalities and stroke rates were similar in the two groups (5.0% vs. 9.1%, p=1.000, and 10.0% vs. 6.1%, p=.627). Interestingly, all four strokes occurred in patients with a type III aortic arch irrespective of transposition type. Primary success rates (80.0% vs. 69.7%, p=.527) and type I endoleak incidences (20.0% vs. 27.3%, p=.744) were not significantly different. During follow up (mean duration 36.9 months), overall survival (89.7% vs. 87.4% at 1 year and 89.7% vs. 79.3% at 3 years; p=.375) and re-intervention free survival rates (78.6% vs. 92.0% at 1 year; 72.0% vs. 62.2% at 3 years, p=.872) were similar in the two groups. Morbidity and mortality were high within the first year of hybrid endovascular therapy for aortic arch disease, implying that candidates for hybrid procedures need to be selected carefully. Hybrid endovascular repair with TAT was found to have peri-operative mortality, stroke, and long-term survival rates comparable with PAT, so hybrid endovascular repair may be considered, irrespective of type of arch reconstruction, when clinically indicated. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Factors Affecting Dental Caries of Preschool Children in Shiraz, 2014

Science.gov (United States)

Shaghaghian, Soheila; Abolvardi, Masoud; Akhlaghian, Marzieh

2018-01-01

Statement of the Problem: Dental caries, the most common infectious disease, can lead to several consequences, including inflammation and bleeding of the gum, abscess formation, tooth loss, and subsequently loss of available space in the arch. Purpose: This study was designed to determine dental caries status of Shiraz preschool children and its related factors. Materials and Method: This cross-sectional study was conducted on the children registered in Shiraz kindergartens in 2014. The study recruited 453 children by randomized cluster sampling. We evaluated the children’s demographic and oral hygiene factors, and their dental caries status using decayed, missed, and filled tooth (dmft) index and prevalence of the children with untreated dental caries. Relationship between the children’s characteristics and their dental caries status was evaluated. Results: Only 119 children (30.1%) were caries-free. The children’s mean dmft index was 3.88(±3.9). After controlling the effect of confounding factors, the children’s dental caries status was significantly associated with variables indicating their socioeconomic status such as fathers’ job, mothers’ education, and number of children in the family. Furthermore, there was a significant association between the children’s dental caries status and their oral hygiene habits such as frequency of tooth brushing. Conclusion: The dental caries status of the studied preschool children was not desirable which could be indicative of the inadequacy of the current preventive programs. To improve this issue, interventional preventive programs such as tooth brushing are recommended. The programs are more necessary for the children of low socioeconomic families and those with poor oral hygiene habits. PMID:29854883

Periodontal and dental effects of surgically assisted rapid maxillary expansion, assessed by using digital study models

Science.gov (United States)

Siqueira, Danilo Furquim; Cardoso, Mauricio de Almeida; Capelozza, Leopoldino; Goldenberg, Dov Charles; Fernandes, Mariana dos Santos

2015-01-01

OBJECTIVE: The present study assessed the maxillary dental arch changes produced by surgically assisted rapid maxillary expansion (SARME). METHODS: Dental casts from 18 patients (mean age of 23.3 years) were obtained at treatment onset (T1), three months after SARME (T2) and 6 months after expansion (T3). The casts were scanned in a 3D scanner (D-250, 3Shape, Copenhagen, Denmark). Maxillary dental arch width, dental crown tipping and height were measured and assessed by ANOVA and Tukey's test. RESULTS: Increased transversal widths from T1 and T2 and the maintenance of these values from T2 and T3 were observed. Buccal teeth tipping also showed statistically significant differences, with an increase in all teeth from T1 to T2 and a decrease from T2 to T3. No statistically significant difference was found for dental crown height, except for left first and second molars, although clinically irrelevant. CONCLUSION: SARME proved to be an effective and stable procedure, with minimum periodontal hazards. PMID:26154457

Relationship Among Dental Students' Class Lecture Attendance, Use of Online Resources, and Performance.

Science.gov (United States)

Azab, Ehab; Saksena, Yun; Alghanem, Tofool; Midle, Jennifer Bassett; Molgaard, Kathleen; Albright, Susan; Karimbux, Nadeem

2016-04-01

This study aimed to evaluate the relationship among dental students' attendance at class lectures, use of online lecture materials, and performance in didactic courses. The study was conducted with second-year predoctoral students at Tufts University School of Dental Medicine during the fall semester of 2014. Three basic science and three preclinical dental courses were selected for evaluation. Online usage for each participant was collected, and a survey with questions about attendance and online behavior was conducted. The final grade for each participant in each selected course was obtained and matched with his or her online usage and attendance. Out of a total 190 students, 146 (77%) participated. The results showed no significant relationship between students' grades and their class attendance or online usage except for a weak negative relationship between class attendance and online usage for the Epidemiology course (pattendance, online usage, and course grades, most of the students reported that having the online resources in addition to the lectures was helpful.

Persistent fifth arch anomalies - broadening the spectrum to include a variation of double aortic arch vascular ring

Energy Technology Data Exchange (ETDEWEB)

Newman, Beverley; Chan, Frandics [Stanford Children' s Hospital and Stanford University, Department of Radiology, Stanford, CA (United States); Hanneman, Kate [University of Toronto, Department of Medical Imaging, Toronto, ON (Canada)

2016-12-15

Fifth arch anomalies are rare and complex and frequently misdiagnosed or mistaken for other entities. We report a double arch vascular ring that is thought to consist of right fourth arch and left fifth arch components, a previously undescribed persistent fifth arch variant. The currently recognized spectrum and classification of fifth arch vascular anomalies are expanded along with illustrative images to justify the proposed changes. Reviewing and expanding the classification of fifth arch anomalies to include a double arch ring variant will promote recognition, correct diagnosis and appropriate management of these anomalies. (orig.)

Relationship between friction force and orthodontic force at the leveling stage using a coated wire.

Science.gov (United States)

Murayama, Masaki; Namura, Yasuhiro; Tamura, Takahiko; Iwai, Hiroaki; Shimizu, Noriyoshi

2013-01-01

The relationship between orthodontic force and friction produced from an archwire and brackets affects the sliding of the wire in the leveling stage. The purpose of this study was to evaluate the relationship between force and friction in a small esthetic nickel-titanium (Ni-Ti) wire. Five esthetic wires (three coated and two plated) and two small, plain Ni-Ti wires (0.012 and 0.014 inches) were used. We performed a three-point bending test according to ISO 15841 and the drawing test with a dental arch model designed with upper linguoversion of the lateral incisor in the arch (displacements of 0.5, 1.0, 2.0 and 3.0 mm), and evaluated the relationship between them. Unloading bending forces of all wires at displacements of less than 1.0 mm were larger than friction forces, but all friction forces at displacements exceeding 2.0 mm were larger than unloading bending forces. The arch likely expands when displacement from the proximal brackets exceeds 1.0 mm. The friction force of a martensite 0.014-inch Ni-Ti wire was significantly greater than those of the other esthetic and austenitic wires. A wire with the smallest possible friction force should be used in cases with more than 1.0 mm displacement.

Relationships between dental hygienists' career attitudes and their retention of practice. Part II. From the results of the Ohio Dentist and Dental Hygiene Surveys.

Science.gov (United States)

Cox, S S; Langhout, K J; Scheid, R C

1993-01-01

This article utilizes findings from the Ohio Dental Hygiene Survey and Ohio Dentist Survey to uncover what specific dental hygiene attitudes exist relative to employment and what factors have led to job termination and to re-entry. Ohio dental hygiene employees are most satisfied with patient relationships, co-worker relationships, and flexible working hours. The dental hygienists are least satisfied with fringe benefits, financial growth, and career creativity. Salary, benefits, nor career longevity were significant factors in determining satisfaction. Dental hygienists who were not working when surveyed, said they would consider returning to practice if a better salary were available, if they could find part-time work, if there were a good wage scale with benefits, or if their own financial need changed. Thirty-six percent of the non-practitioners said they would not ever consider returning to practice due to working conditions, establishment of a new career, or inadequate compensation. Dentist employers stated that they were satisfied or very satisfied with their dental hygienists' patient care and contribution to the practice.

Oral cavity evaluation and dental chart registration of coati (Nasua nasua) in captivity

OpenAIRE

Freitas, Elisângela P; Rahal, Sheila Canevese; Teixeira, Carlos Roberto; Teixeira, Rodrigo Hidalgo Friciello; Mendes, Guilherme Martines Teixeira; Gioso, Marco Antonio

2008-01-01

The aims of this study were to develop a dental chart, evaluate any oral cavity disease, develop gypsum models of the dental arches, and to register the occlusions found in coatis (Nasua nasua) in captivity. Formulation of the dental chart was assisted by intraoral radiographs from the head of an adult coati cadaver of the same species with the following dental formula: I 3/3, C 1/1, P 4/3, M 2/2. Seven live coatis of the Nasua nasua species were evaluated. Five of the seven coatis presented ...

Multivariate analysis on unilateral cleft lip and palate treatment outcome by EUROCRAN index: A retrospective study.

Science.gov (United States)

Yew, Ching Ching; Alam, Mohammad Khursheed; Rahman, Shaifulizan Abdul

2016-10-01

This study is to evaluate the dental arch relationship and palatal morphology of unilateral cleft lip and palate patients by using EUROCRAN index, and to assess the factors that affect them using multivariate statistical analysis. A total of one hundred and seven patients from age five to twelve years old with non-syndromic unilateral cleft lip and palate were included in the study. These patients have received cheiloplasty and one stage palatoplasty surgery but yet to receive alveolar bone grafting procedure. Five assessors trained in the use of the EUROCRAN index underwent calibration exercise and ranked the dental arch relationships and palatal morphology of the patients' study models. For intra-rater agreement, the examiners scored the models twice, with two weeks interval in between sessions. Variable factors of the patients were collected and they included gender, site, type and, family history of unilateral cleft lip and palate; absence of lateral incisor on cleft side, cheiloplasty and palatoplasty technique used. Associations between various factors and dental arch relationships were assessed using logistic regression analysis. Dental arch relationship among unilateral cleft lip and palate in local population had relatively worse scoring than other parts of the world. Crude logistics regression analysis did not demonstrate any significant associations among the various socio-demographic factors, cheiloplasty and palatoplasty techniques used with the dental arch relationship outcome. This study has limitations that might have affected the results, example: having multiple operators performing the surgeries and the inability to access the influence of underlying genetic predisposed cranio-facial variability. These may have substantial influence on the treatment outcome. The factors that can affect unilateral cleft lip and palate treatment outcome is multifactorial in nature and remained controversial in general. Copyright © 2016 Elsevier Ireland Ltd. All

Current status of collaborative relationships between dialysis facilities and dental facilities in Japan: results of a nationwide survey.

Science.gov (United States)

Yoshioka, Masami; Shirayama, Yasuhiko; Imoto, Issei; Hinode, Daisuke; Yanagisawa, Shizuko; Takeuchi, Yuko

2015-02-12

Recent studies have reported an association between periodontal disease and mortality among dialysis patients. Therefore, preventive dental care should be considered very important for this population. In Japan, no systematic education has been undertaken regarding the importance of preventive dental care for hemodialysis patients--even though these individuals tend to have oral and dental problems. The aim of this study was to investigate the current state of collaborative relationships between hemodialysis facilities and dental services in Japan and also to identify strategies to encourage preventive dental visits among hemodialysis outpatients. A nationwide questionnaire on the collaborative relationship between dialysis facilities and dental facilities was sent by mail to all medical facilities in Japan offering outpatient hemodialysis treatment. Responses were obtained from 1414 of 4014 facilities (35.2%). Among the 1414 facilities, 272 (19.2%) had a dental service department. Approximately 100,000 dialysis outpatients were receiving treatment at these participating facilities, which amounts to one-third of all dialysis patients in Japan. Of those patients, 82.9% received hemodialysis at medical facilities without dental departments. Only 87 of 454 small clinics without in-house dental departments (19.2%) had collaborative registered dental clinics. Medical facilities with registered dental clinics demonstrated a significantly more proactive attitude to routine collaboration on dental matters than facilities lacking such clinics. Our nationwide survey revealed that most dialysis facilities in Japan have neither an in-house dental department nor a collaborative relationship with a registered dental clinic. Registration of dental clinics appears to promote collaboration with dental facilities on a routine basis, which would be beneficial for oral health management in hemodialysis patients.

Profile of Dental Caries in Teenagers in Mumbai City Visiting Nair Hospital Dental College.

Science.gov (United States)

Banga, Kulvinder Singh; Rastogi, Sweta; Mistry, Siddhi

2018-01-01

Witnessing the alarming rise and pattern of distribution of dental caries worldwide, the need of the hour is to take initiative in preventing the spread further. This survey was conducted to determine the occurrence of dental caries and its associated risk factors in teenagers of Mumbai city who visited Nair Hospital Dental College. The objective of the study was to analyze the current dietary habits, oral hygiene status, and the number of sugar exposures in teenagers by a questionnaire followed by clinical examination which was carried out using International Caries Detection and Assessment System (ICDAS) II to detect the profile of dental caries. The data obtained from the questionnaire and examination were analyzed using Chi-square test. The survey showed that, out of the 300 teenagers examined, 67% visited the dentist only when they were symptomatic. Around 60% consumed sweets 2-3 times/day. A major percentage, 89%, consumed sweets irrespective of meal time and 52% consumed aerated drinks often. Only 16% used appropriate brushing techniques and 93% were not aware if their toothpaste was fluoridated. ICDAS II revealed that a total number of teeth requiring preventive treatment ranged from 8.3% to 14% and total number of teeth requiring definitive treatment ranged from 36% to 48%. It was found that tooth most commonly treated was 36 followed by tooth number 46 showing that the incidence of caries is higher in lower arch. Most of the teenagers had a high rate of sweet consumption in between meals and poor knowledge of brushing techniques, fluoridated toothpaste, interdental aids, and mouthrinses. ICDAS showed a high incidence of caries in teenagers, especially in the lower arch. ICDAS II showed good accuracy in differentiating between noncavitated and cavitated lesions which helps to provide an accurate treatment plan for teenagers so that it prevents the progression of the lesion.

Study on the relationship between Helicobacter pylori in the dental plaque and the occurrence of dental caries or oral hygiene index.

Science.gov (United States)

Liu, Ying; Lin, Huanjian; Bai, Yang; Qin, Xiaoshu; Zheng, Xin; Sun, Yong; Zhang, Yali

2008-08-01

The aims of our study were to determine the presence of Helicobacter pylori DNA in the dental plaque of Chinese children aged 3-6 years by nested polymerase chain reaction (PCR) and to investigate the relationship between this infection and the occurrence of dental caries or oral hygiene index. Two hundred and fourteen children from a kindergarten in Guangzhou City of China were evaluated. The children's plaques were assessed by plaque indices of Quigley-Hein. Dental plaque was analyzed using nested PCR for two sets of primers directed to the 860-bp fragment of H. pylori genomic DNA, which have been reported to be highly sensitive and specific by other researchers. H. pylori was detected in dental plaque samples from 126 children, and 70 children with dental caries carried H. pylori in dental plaque. Of these children without infection, only 36 of 88 suffered dental caries. Besides, the average dental plaque index of 126 H. pylori-positive children was higher than that of 88 children without infection. In the present study, there was a significant correlation between H. pylori infection and dental caries or dental hygiene. The oral cavity may be a reservoir for H. pylori infection in children. H. pylori in dental plaque may play a role in the occurrence of dental caries, and poor oral hygiene may represent a risk factor for H. pylori in the oral cavity.

Prosthodontic decision-making relating to dentitions with compromised molars: the perspective of Swedish General Dental Practitioners.

Science.gov (United States)

Korduner, E-K; Collin Bagewitz, I; Vult von Steyern, P; Wolf, E

2016-12-01

The aim of this investigation was to study the clinical prosthodontic decision-making process relating to dentitions with compromised molars among Swedish general dental practitioners (GDPs). Eleven Swedish GDPs were purposively selected, and all agreed to participate. Then, in-depth, semi-structured interviews were conducted and covered treatment considerations concerning two authentic patient cases, initially with complete dental arches, and later, a final treatment based on a shortened dental arch (SDA) was discussed. The cases involved patients with compromised teeth situated mainly in the molar regions. One patient suffered from extensive caries and the other from severe periodontal disease. Qualitative content analysis was used to analyse the data. In the systematic analysis, two main categories were identified: holistic and functional approach. Among the interviewed GDPs, focus was put on patients' needs, background history and motivation for treatment as well as the preservation of molar support. Within the limitations of this study, the following can be concluded: keeping a dental arch with molars seems to be important to Swedish general dental practitioners. The SDA concept does not seem to have a substantial impact on the prosthodontic decision-making relating to dentitions with compromised molars. The dentist's experiences, as well as colleagues' or consulting specialist advice together with aetiological factors and the patient's individual situation, influence the decision-making more than the SDA concept. The conflicting results in the prosthetic decision-making process concerning the relevance of age and the need for molar support need further investigation, for example based on decisions made in the dentist's own clinical practice. © 2016 John Wiley & Sons Ltd.

Oral cavity evaluation and dental chart registration of coati (Nasua nasua) in captivity.

Science.gov (United States)

Freitas, Elisângela P; Rahal, Sheila C; Teixeira, Carlos R; Teixeira, Rodrigo H F; Mendes, Guilherme M; Gioso, Marco A

2008-06-01

The aims of this study were to develop a dental evaluate any oral cavity disease, develop gypsum models of the dental arches, and to register the occlusions found in coatis (Nasua nasua) in captivity Formulation of the dental chart was assisted by intraoral radiographs from the head of an adult coati cadaver of the same species with the following dental formula.: I 3/3, C 1/1, P 4/3, M 2/2. Seven live coatis of the Nasua nasua species were evaluated. Five of the seven coatis presented with various dental abnormalities as follows: dental plaque (71.4 0%), gingivitis (71.4 %), periodontitis (57.1 %), dental stain (42.9 %), dental abrasion (57.1 %), dental fracture (57.1 %), pulp exposure (42.9 %), malocclusion (57.1 %) and supernumerary teeth (14.2 %).

Neonatal aortic arch reconstruction avoiding circulatory arrest and direct arch vessel cannulation.

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Tchervenkov, C I; Korkola, S J; Shum-Tim, D; Calaritis, C; Laliberté, E; Reyes, T U; Lavoie, J

2001-11-01

Aortic arch reconstruction in neonates routinely requires deep hypothermic circulatory arrest. We reviewed our experience with techniques of continuous low-flow cerebral perfusion (LFCP) avoiding direct arch vessel cannulation. Eighteen patients, with a median age of 11 days (range 1 to 85 days) and a mean weight of 3.2 +/- 0.8 kg, underwent aortic arch reconstruction with LFCP. Seven had biventricular repairs with arch reconstruction, 9 underwent the Norwood operation and 2 had isolated arch repairs. In 1 Norwood and 7 biventricular repair patients, LFCP was maintained by advancing the cannula from the distal ascending aorta into the innominate artery. In 8 of 9 Norwood patients, LFCP was maintained by directing the arterial cannula into the pulmonary artery confluence and perfusing the innominate artery through the right modified Blalock-Taussig shunt fully constructed before cannulation for cardiopulmonary bypass. In 2 patients requiring isolated arch reconstruction, the ascending aorta was cannulated and the cross-clamp was applied just distal to the innominate artery. LFCP was maintained at 0.6 +/- 0.2 L x min(-1) x m(-2) for 41.0 +/- 13.9 minutes at 18.5 degrees C +/- 1.1 degrees C. In 10 of the 18 patients, blood pressure during LFCP was 15 +/- 8 mm Hg remote from the innominate artery (left radial, umbilical or femoral arteries). In 8 of the 18 patients, right radial pressure during LFCP was 24 +/- 10 mm Hg. The mean mixed-venous saturation was 79.8% +/- 10% during LFCP. Two patients had preoperative seizures, whereas none had seizures postoperatively. One patient died. Neonatal aortic arch reconstruction is possible without circulatory arrest or direct arch vessel cannulation. These techniques maintained adequate mixed-venous oxygen saturations with no associated adverse neurologic outcomes.

An anthropometric analysis of facial height, arch length, and palatal rugae in the Indian and Nepalese population.

Science.gov (United States)

Kallianpur, Shreenivas; Desai, Ami; Kasetty, Sowmya; Sudheendra, Us; Joshi, Prathamesh

2011-01-01

A country such as India abounds with diverse population groups with distinct anthropometric characteristics. Among these, numerous Nepalese population groups are present in different states of India comprising one of the most common immigrant races. The aim of the study is to compare two distinct races, Indians and Nepalese on the basis of facial height proportions, arch length and palatal rugae patterns and assess their significance in racial identification. A total of 120 subjects comprising of 60 Indians and 60 Nepalese were selected, with each group including 30 males and 30 females. Facial heights were measured using sliding digital calipers, arch lengths with the help of a brass wire and rugae patterns were traced on dental casts obtained with alginate impressions. Facial height measurements did not give significant results for racial or gender identification of given races. Differences between arch length parameters were found to be significant between the two population groups. Secondary and fragmentary palatal rugae forms were found to be more common in Nepalese than Indians. The Indian and Nepalese have similar anthropometric characteristics with regard to facial height. However, arch length and palatal rugae characteristics vary between the two races.

Surgical modification for preventing a gothic arch after aortic arch repair without the use of foreign material.

Science.gov (United States)

Seo, Dong-Man; Park, Jiyoung; Goo, Hyun Woo; Kim, Young Hwue; Ko, Jae-Kon; Jhang, Won Kyoung

2015-04-01

Systemic hypertension is the main late complication after arch reconstruction in patients with arch obstruction. Gothic arch geometry is suspected to be one of its possible causes. Accordingly, we evaluated here if a modified arch repair technique using an autologous pulmonary patch is effective in preventing gothic arch development. Fifty infants who underwent arch repair with either a modified (n = 17) or conventional (n = 33) technique between January 2006 and August 2012 by a single surgeon were retrospectively reviewed. Arch geometry was compared using three categories (gothic, crenel or roman), classified by the height/width (H/W) ratio and the arch angle measured in computed tomography. No gothic arch geometry was observed in the modified group, whereas it was observed in 9 cases in the conventional group (P = 0.005). Moreover, reintervention for arch restenosis was performed only in the conventional group (n = 4; P = 0.29). No associated complications were observed, although the selective cerebral perfusion time was longer in the modified group than in the conventional group (28.5 ± 6.2 vs 17.1 ± 9.9 min; P gothic arch geometry, but also as equally safe in terms of early clinical outcomes as conventional arch reconstruction techniques. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Effect of Polyvinyl Siloxane Viscosity on Accuracy of Dental Implant Impressions

OpenAIRE

Ghahremanloo, Ahmad; Seifi, Mahdieh; Ghanbarzade, Jalil; Abrisham, Seyyed Mohammad; Javan, Rashid Abdolah

2017-01-01

Objectives: The aim of this study was to compare the accuracy of dental implant impressions obtained by a combination of different impression techniques and viscosities of polyvinyl siloxane (PVS).Materials and Methods: Four parallel fixtures were placed between mental foramina in a master model of lower dental arch. Three different viscosities (putty/light body, medium body/light body, and monophase: heavy body) and direct and indirect techniques (six groups) were used, and seven impressions...

What is the relationship between emotional intelligence and dental student clinical performance?

Science.gov (United States)

Victoroff, Kristin Zakariasen; Boyatzis, Richard E

2013-04-01

Emotional intelligence has emerged as a key factor in differentiating average from outstanding performers in managerial and leadership positions across multiple business settings, but relatively few studies have examined the role of emotional intelligence in the health care professions. The purpose of this study was to examine the relationship between emotional intelligence (EI) and dental student clinical performance. All third- and fourth-year students at a single U.S. dental school were invited to participate. Participation rate was 74 percent (100/136). Dental students' EI was assessed using the Emotional Competence Inventory-University version (ECI-U), a seventy-two-item, 360-degree questionnaire completed by both self and other raters. The ECI-U measured twenty-two EI competencies grouped into four clusters (Self-Awareness, Self-Management, Social Awareness, and Relationship Management). Clinical performance was assessed using the mean grade assigned by clinical preceptors. This grade represents an overall assessment of a student's clinical performance including diagnostic and treatment planning skills, time utilization, preparation and organization, fundamental knowledge, technical skills, self-evaluation, professionalism, and patient management. Additional variables were didactic grade point average (GPA) in Years 1 and 2, preclinical GPA in Years 1 and 2, Dental Admission Test academic average and Perceptual Ability Test scores, year of study, age, and gender. Multiple linear regression analyses were conducted. The Self-Management cluster of competencies (b=0.448, pintelligence may be an important predictor of clinical performance, which has important implications for students' development during dental school.

Dental Calculus Arrest of Dental Caries

OpenAIRE

Keyes, Paul H.; Rams, Thomas E.

2016-01-01

Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human t...

RARE BRANCHIAL ARCH ANOMALIES

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Jayanta Kumar

2016-03-01

Full Text Available AIM Amongst the branchial arch anomalies third arch anomaly occurs rarely and more so the fourth arch anomalies. We present our experience with cases of rare branchial arch anomalies. PATIENTS AND METHODS From June 2006 to January 2016, cases having their external opening in the lower third of sternocleidomastoid muscle with the tract going through thyroid gland and directing to pyriform sinus (PFS or cysts with internal opening in the PFS were studied. RESULTS No fourth arch anomaly was encountered. One cyst with internal opening which later on formed a fistula, three fistulae from beginning and two sinuses were encountered. The main stay of diagnosis was the fistula in the PFS and the tract lying posterior to the internal carotid artery. Simple excision technique with a small incision around the external opening was done. There was no recurrence. CONCLUSION Third arch fistula is not very rare as it was thought. Internal fistula is found in most of the cases. Though radiological investigations are helpful, fistulae can be diagnosed clinically and during operation. Extensive operation of the neck, mediastinum and pharynx is not required.

The relationship between childhood body weight and dental caries experience: an umbrella systematic review protocol

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Susan J. Carson

2017-10-01

Full Text Available Abstract Background Obesity and dental caries are global public health problems which can impact in childhood and throughout the life course. In simple terms, childhood dental caries and body weight are linked via the common risk factor of diet. An association between dental caries and obesity has been described in a number of studies and reviews. However, similarly, a relationship has also been noted between low body weight and caries experience in children. This protocol will provide the framework for an umbrella review to address the following question: Does the available evidence support a relationship between dental caries experience and body weight in the child population? Methods This review protocol outlines the process to carry out an umbrella systematic review which will synthesise previous reviews of childhood dental caries experience and body weight. An umbrella review methodology will be used to examine the methodological and reporting quality of existing reviews. Discussion The final umbrella review aims to aggregate the available evidence in order to provide a summary for policymakers and to inform healthcare interventions. Systematic review registration PROSPERO CRD42016047304

The relationship between childhood body weight and dental caries experience: an umbrella systematic review protocol.

Science.gov (United States)

Carson, Susan J; Abuhaloob, Lamis; Richards, Derek; Hector, Mark P; Freeman, Ruth

2017-10-25

Obesity and dental caries are global public health problems which can impact in childhood and throughout the life course. In simple terms, childhood dental caries and body weight are linked via the common risk factor of diet. An association between dental caries and obesity has been described in a number of studies and reviews. However, similarly, a relationship has also been noted between low body weight and caries experience in children. This protocol will provide the framework for an umbrella review to address the following question: Does the available evidence support a relationship between dental caries experience and body weight in the child population? This review protocol outlines the process to carry out an umbrella systematic review which will synthesise previous reviews of childhood dental caries experience and body weight. An umbrella review methodology will be used to examine the methodological and reporting quality of existing reviews. The final umbrella review aims to aggregate the available evidence in order to provide a summary for policymakers and to inform healthcare interventions. PROSPERO CRD42016047304.

Relationship between friction force and orthodontic force at the leveling stage using a coated wire

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Masaki MURAYAMA

2013-12-01

Full Text Available The relationship between orthodontic force and friction produced from an archwire and brackets affects the sliding of the wire in the leveling stage. Objective: The purpose of this study was to evaluate the relationship between force and friction in a small esthetic nickel-titanium (Ni-Ti wire. Material and Methods: Five esthetic wires (three coated and two plated and two small, plain Ni-Ti wires (0.012 and 0.014 inches were used. We performed a three-point bending test according to ISO 15841 and the drawing test with a dental arch model designed with upper linguoversion of the lateral incisor in the arch (displacements of 0.5, 1.0, 2.0 and 3.0 mm, and evaluated the relationship between them. Results: Unloading bending forces of all wires at displacements of less than 1.0 mm were larger than friction forces, but all friction forces at displacements exceeding 2.0 mm were larger than unloading bending forces. The arch likely expands when displacement from the proximal brackets exceeds 1.0 mm. The friction force of a martensite 0.014-inch Ni-Ti wire was significantly greater than those of the other esthetic and austenitic wires. Conclusions: A wire with the smallest possible friction force should be used in cases with more than 1.0 mm displacement.

Cable strengthened arches

NARCIS (Netherlands)

Kamerling, M.W.

2013-01-01

The structural efficiency of arches, subjected to several variable loads, can be increased by strengthening these arches with cables. For these structures it can be necessary, especially in case the permanent load is small, to post-tension the cables to avoid any compression acting on the cables. A

Effect of Polyvinyl Siloxane Viscosity on Accuracy of Dental Implant Impressions.

Science.gov (United States)

Ghahremanloo, Ahmad; Seifi, Mahdieh; Ghanbarzade, Jalil; Abrisham, Seyyed Mohammad; Javan, Rashid Abdolah

2017-01-01

The aim of this study was to compare the accuracy of dental implant impressions obtained by a combination of different impression techniques and viscosities of polyvinyl siloxane (PVS). Four parallel fixtures were placed between mental foramina in a master model of lower dental arch. Three different viscosities (putty/light body, medium body/light body, and monophase: heavy body) and direct and indirect techniques (six groups) were used, and seven impressions were obtained from each group (n=42). To measure the accuracy of impressions, drift, horizontal, and vertical angles of the implants, as well as the hex rotation of the implants in casts were evaluated using a digitizer device (1μm accuracy), in comparison with master arch. Data were analyzed using five-factor two-way ANOVA and Tukey's post-hoc test. The accuracy of impressions was assessed and the results showed that direct technique was not significantly different from indirect technique (P>0.05). Also, there were no significant differences between the mentioned viscosities except for the horizontal angle (P=0.006). Viscosity of impression materials is of high significance for the accuracy of dental impressions.

The relationship between the dental health knowledge and oral hygiene index of the deaf

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Lilis Nurliyanasari

2009-07-01

Full Text Available Oral hygiene index can be influenced by behaviour factor. Behavior has three domain consist of knowledge, attitude, and practice. Knowledge will change the behaviour of society which next affects to oral hygiene index. The purpose of the research was to know the relationship between the dental health knowledge and oral and dental hygiene index of the deaf. The research was analytic with the cross-sectional method on 63 subjects on 3,4,5 and 6 level class at hearing impaired in Magelang, obtained using the total sampling. Evaluation of dental health knowledge was viewed from the questionnaire. Oral Hygiene Index-Simplified by Green dan Vermillion used to measured oral hygiene index. The research result showed that 65.08%of the deaf on 3,4,5 and 6 level class at hearing impaired in Magelang was in the good category, OHI-S was in the moderate category. Based on Chi-square test there was no significant relationship between the dental health knowledge and oral hygiene index of the deaf at hearing impaired in Magelang.

Difference between manual and digital measurements of dental arches of orthodontic patients.

Science.gov (United States)

Jiménez-Gayosso, Sandra Isabel; Lara-Carrillo, Edith; López-González, Saraí; Medina-Solís, Carlo Eduardo; Scougall-Vilchis, Rogelio José; Hernández-Martínez, César Tadeo; Colomé-Ruiz, Gabriel Eduardo; Escoffié-Ramirez, Mauricio

2018-06-01

The objective of this study was to compare the differences between the measurements performed manually to those obtained using a digital model scanner of patients with orthodontic treatment.A cross-sectional study was performed in a sample of 30 study models from patients with permanent dentition who attended a university clinic between January 2010 and December 2015. For the digital measurement, a Maestro 3D Ortho Studio scanner (Italy) was used and Mitutoyo electronic Vernier calipers (Kawasaki, Japan) were used for manual measurement. The outcome variables were the measurements for maxillary intercanine width, mandibular intercanine width, maxillary intermolar width, mandibular intermolar width, overjet, overbite, maxillary arch perimeter, mandibular arch perimeter, and palate height. The independent variables, besides age and sex, were a series of arc characteristics. The Student t test, paired Student t test, and Pearson correlation in SPSS version 19 were used for the analysis.Of the models, 60% were from women. Two of nine measurements for pre-treatment and 6 of 9 measurements for post-treatment showed a difference. The variables that were different between the manual and digital measurements in the pre-treatment were maxillary intermolar width and palate height (P manually and digitally showed certain similarities for both vertical and transverse measurements. There are many advantages offered to the orthodontist, such as easy storage; savings in time and space; facilitating the reproducibility of information; and conferring the security of not deteriorating over time. Its main disadvantage is the cost.

Idiopathic dental pulp calcifications in a tertiary care setting in South India.

Science.gov (United States)

Satheeshkumar, P S; Mohan, Minu P; Saji, Sweta; Sadanandan, Sudheesh; George, Giju

2013-01-01

Dental pulp calcifications are unique and represent the dental pulp regenerative process. Dental pulp calcifications are sometimes routine findings in oral radiographs and may later serve as an important diagnostic criterion for a hidden aspect of systemic illness. The purpose of this study was to assess the patterns and prevalence of idiopathic dental pulp calcifications in a tertiary care setting in South India. A total of 227 patients were included in the study fulfilling the inclusion criteria. Age range of the study population was from 15 to 70 years. Teeth were examined under digital panoramic radiograph. The presence or absence of pulp stones was recorded. The presence of pulp stone were categorized according to the types classified as Type I, Type IA, Type II, Type IIA, Type II B, and Type III. The frequency of occurrence of pulp stones with sex, tooth type, dental arches, and types were compared with the types of calcification. Total no. of patients with pulpal calcification were 227 [females 133 (58.59%) and males 94 (41.40%)]. The most common type between both sexes was Type I (48%). Total no. of teeth with calcification was 697; maxilla (48%), mandible (52%). The prevalence of pulp stone was found to be higher in the molars in both the arches. Most no. of pulp stones are reported at the third and fourth decade of life. Idiopathic dental pulp calcifications are incidental radiographic findings of the pulp tissue and also may be an indicator of underlying disease.

Immediate placement of dental implants in the mandible

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Gurkar Haraswarupa Puttaraju

2013-01-01

Full Text Available This case describes extraction of teeth in the mandibular arch, i.e., 41 42 43 44 45 51 52 53 54 55 56 57 58 (grade two mobility, followed by immediate placement of four dental implants (3i biomet, two in the 45 55 region and two dental implants in 12 21 region. A prefabricated provisional mandibular denture was immediately placed. The purpose of immediate placement was to aid the patient resume his professional duties the next day itself along with esthetic and functional comfort, psychological well-being and most importantly preserving the remaining tissue in a healthy condition.

Assessment of relationship between oral health behavior, oral hygiene and gingival status of dental students

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Afsheen Lalani

2015-01-01

Conclusion: Thus, it is concluded that there is a significant relationship between the oral health behavior, oral hygiene, and gingival status of dental students. Dental students with better self-reported oral health behavior had lower plaque and gingival scores indicating a better attitude toward oral health.

Right circumflex retro-oesophageal aortic arch with coarctation of a high-positioned right arch

International Nuclear Information System (INIS)

Ahn, Kyung-Sik; Yong, Hwan Seok; Woo, Ok Hee; Kang, Eun-Young; Lee, Joo-Won

2007-01-01

We present a rare case of right circumflex retro-oesophageal aortic arch with coarctation of a high-positioned right arch. A 7-month-old boy presented with a cardiac murmur. Cardiac situs was normal and there was no evidence of an intracardiac shunt or patent ductus arteriosus. MR aortography revealed a right aortic arch that was high-positioned, tortuous and narrowed. This right aortic arch crossed the midline behind the oesophagus and continued as a left-sided descending aorta. The left common carotid and subclavian arteries arose from a large branching vascular structure that derived from the top of the left-sided descending aorta. The right common carotid artery arose from the ascending aorta. The proximal portion of the right common carotid artery showed very severe stenosis and poststenotic dilatation. The right subclavian artery originated distal to the narrowed and tortuous segment of the aortic arch. (orig.)

Foot medial longitudinal-arch deformation during quiet standing and gait in subjects with medial tibial stress syndrome

DEFF Research Database (Denmark)

Bandholm, Thomas Quaade; Boysen, Lisbeth; Haugaard, Stine

2008-01-01

The objective of this study was to investigate (1) if subjects with medial tibial stress syndrome demonstrate increased navicular drop and medial longitudinal-arch deformation during quiet standing and gait compared with healthy subjects, and (2) the relationship between medial longitudinal-arch ...

Aortic arch malformations

Energy Technology Data Exchange (ETDEWEB)

Kellenberger, Christian J. [University Children' s Hospital, Department of Diagnostic Imaging, Zuerich (Switzerland)

2010-06-15

Although anomalies of the aortic arch and its branches are relatively uncommon malformations, they are often associated with congenital heart disease. Isolated lesions may be clinically significant when the airways are compromised by a vascular ring. In this article, the development and imaging appearance of the aortic arch system and its various malformations are reviewed. (orig.)

Aortic arch malformations

International Nuclear Information System (INIS)

Kellenberger, Christian J.

2010-01-01

Although anomalies of the aortic arch and its branches are relatively uncommon malformations, they are often associated with congenital heart disease. Isolated lesions may be clinically significant when the airways are compromised by a vascular ring. In this article, the development and imaging appearance of the aortic arch system and its various malformations are reviewed. (orig.)

Profile of dental caries in teenagers in Mumbai City visiting Nair Hospital Dental College

Directory of Open Access Journals (Sweden)

Kulvinder Singh Banga

2018-01-01

Full Text Available Background: Witnessing the alarming rise and pattern of distribution of dental caries worldwide, the need of the hour is to take initiative in preventing the spread further. Aim: This survey was conducted to determine the occurrence of dental caries and its associated risk factors in teenagers of Mumbai city who visited Nair Hospital Dental College. Materials and Methods: The objective of the study was to analyze the current dietary habits, oral hygiene status, and the number of sugar exposures in teenagers by a questionnaire followed by clinical examination which was carried out using International Caries Detection and Assessment System (ICDAS II to detect the profile of dental caries. Statistical Analysis: The data obtained from the questionnaire and examination were analyzed using Chi-square test. Results: The survey showed that, out of the 300 teenagers examined, 67% visited the dentist only when they were symptomatic. Around 60% consumed sweets 2–3 times/day. A major percentage, 89%, consumed sweets irrespective of meal time and 52% consumed aerated drinks often. Only 16% used appropriate brushing techniques and 93% were not aware if their toothpaste was fluoridated. ICDAS II revealed that a total number of teeth requiring preventive treatment ranged from 8.3% to 14% and total number of teeth requiring definitive treatment ranged from 36% to 48%. It was found that tooth most commonly treated was 36 followed by tooth number 46 showing that the incidence of caries is higher in lower arch. Conclusion: Most of the teenagers had a high rate of sweet consumption in between meals and poor knowledge of brushing techniques, fluoridated toothpaste, interdental aids, and mouthrinses. ICDAS showed a high incidence of caries in teenagers, especially in the lower arch. ICDAS II showed good accuracy in differentiating between noncavitated and cavitated lesions which helps to provide an accurate treatment plan for teenagers so that it prevents the

Dental and Chronological Ages as Determinants of Peak Growth Period and Its Relationship with Dental Calcification Stages.

Science.gov (United States)

Litsas, George; Lucchese, Alessandra

2016-01-01

To investigate the relationship between dental, chronological, and cervical vertebral maturation growth in the peak growth period, as well as to study the association between the dental calcification phases and the skeletal maturity stages during the same growth period. Subjects were selected from orthodontic pre-treatment cohorts consisting of 420 subjects where 255 were identified and enrolled into the study, comprising 145 girls and 110 boys. The lateral cephalometric and panoramic radiographs were examined from the archives of the Department of Orthodontics, Aristotle University of Thessaloniki, Greece. Dental age was assessed according to the method of Demirjian, and skeletal maturation according to the Cervical Vertebral Maturation Method. Statistical elaboration included Spearman Brown formula, descriptive statistics, Pearson's correlation coefficient and regression analysis, paired samples t-test, and Spearman's rho correlation coefficient. Chronological and dental age showed a high correlation for both gender(r =0.741 for boys, r = 0.770 for girls, pStage IV for both males (r=0.554) and females (r=0.68). The lowest correlation was for the CVM Stage III in males (r=0.433, pStage II in females (r=0.393, p>0.001). The t-test revealed statistically significant differences between these variables (pstages was determined. The second molars showed the highest correlation with CVM stages (CVMS) (r= 0.65 for boys, r = 0.72 for girls). Dental age was more advanced than chronological for both boys and girls for all CVMS. During the peak period these differences were more pronounced. Moreover, all correlations between skeletal and dental stages were statistically significant. The second molars showed the highest correlation whereas the canines showed the lowest correlation for both gender.

Inter-relationship of intelligence-quotient and self-concept with dental caries amongst socially handicapped orphan children.

Science.gov (United States)

Virk, Pks; Jain, R L; Pathak, A; Sharma, U; Rajput, J S

2012-01-01

India has been the focus of many health surveys among normal, physically, and mentally handicapped children. However, the data, concerning oral health conditions of socially handicapped children living in orphanages, are scanty. To study the effect of parental inadequacy, environmental deprivation, and emotional disturbances on dental caries through intelligence quotient (IQ) and self-concept in orphan children and also to co-relate dental caries with different levels of IQ and self-concept. The study was carried out amongst socially handicapped children living in orphanages. 100 children in the age group of 10-14 years from orphanages were selected. Malin's Intelligence Scale for Indian Children (MISIC) was used to assess the intelligence quotient; self-concept questionnaire to assess self-concept of the child and recording of dental caries status of children was done as per WHO Index (1997). To assess the relationship of dental caries with IQ, student's unpaired t-test was used and; to find the relationship between self-concept and dental caries, Karl-Pearson's coefficient of co-relation was applied. the children in orphanages had a lower IQ and high caries experience but had an above average self-concept. There was also no co-relation between dental caries and self-concept. Orphan children, being socially handicapped, are at an increased risk for dental caries due to a lower IQ level, parental deprivation, and institutionalization. Moreover, lack of co-relation between dental caries and self-concept could be explained by the fact that dental caries is a lifelong process whereas different dimensions of self-concept are in a state of constant flux.

Finite element analysis of helical flows in human aortic arch: A novel index

OpenAIRE

Lee, Cheng-Hung; Liu, Kuo-Sheng; Jhong, Guan-Heng; Liu, Shih-Jung; Hsu, Ming-Yi; Wang, Chao-Jan; Hung, Kuo-Chun

2014-01-01

This study investigates the helical secondary flows in the aortic arch using finite element analysis. The relationship between helical flow and the configuration of the aorta in patients of whose three-dimensional images constructed from computed tomography scans was examined. A finite element model of the pressurized root, arch, and supra-aortic vessels was developed to simulate the pattern of helical secondary flows. Calculations indicate that most of the helical secondary flow was formed i...

The relationship between sleep habits and academic performance in dental students in Croatia.

Science.gov (United States)

Valic, M; Pecotic, R; Lusic, L; Peros, K; Pribudic, Z; Dogas, Z

2014-11-01

It is well accepted that sleep and lifestyle habits affect academic success in students. However, sleep patterns and sleep problems amongst dental students have been insufficiently addressed in the literature. The purpose of this study was to evaluate sleep habits of dental students and the relationship between sleep habits and academic performance. A self-administered questionnaire on sleep habits, academic performance and lifestyle was administered. The participants were 447 dental students from Split University Dental Medicine School and Zagreb University Dental Medicine School from the six academic years. The subjects were classified into two groups based on academic success (high-performing vs. low-performing students) for comparison of sleep and lifestyle habits. Amongst the whole group of students, average bedtime and wake time during weekday was significantly earlier compared with weekend. Main findings indicate that students with high academic performance had earlier bedtimes during weekdays and weekends, earlier wake times during weekends and shorter sleep latency compared with low academic performing students. Self-reported academic performance of dental students in Croatia is associated with timing of sleep and wakefulness, rather than with total sleep time duration. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Islamic Architecture and Arch

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Mohammed Mahbubur Rahman

2015-01-01

Full Text Available The arch, an essential architectural element since the early civilizations, permitted the construction of lighter walls and vaults, often covering a large span. Visually it was an important decorative feature that was trans-mitted from architectural decoration to other forms of art worldwide. In early Islamic period, Muslims were receiving from many civilizations, which they improved and re-introduced to bring about the Renaissance. Arches appeared in Mesopotamia, Indus, Egyptian, Babylonian, Greek and Assyrian civilizations; but the Romans applied the technique to a wide range of structures. The Muslims mastered the use and design of the arch, employed for structural and functional purposes, progressively meeting decorative and symbolic pur-poses. Islamic architecture is characterized by arches employed in all types of buildings; most common uses being in arcades. This paper discusses the process of assimilation and charts how they contributed to other civilizations.

The Relationship between Positive Well-Being and Academic Assessment: Results from a Prospective Study on Dental Students

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Cristina Teodora Preoteasa

2016-01-01

Full Text Available Background. Presumably, the academic stress that builds throughout the academic year has a negative effect on dental students’ psychological well-being and may have a relationship with academic performance. This research aimed to analyse the variation of positive well-being in second-year dental students, across the academic semester, in relation to consecutive examinations as part of academic assessment system (1 and to observe the relationship between academic performance during semester evaluation period and dental students’ positive well-being (2. Methods. A prospective study was conducted on second-year dental students, data on positive well-being being collected with WHO-Five Well-Being Index (WHO-5, at the beginning of the semester and after three consecutive mandatory examinations. Results. One hundred and forty-six dental students were included (77% response rate. Repeated ANOVA showed a significant progressive decline of positive well-being over the semester, which was clinically significant for an important part of them. Students who performed better in the semester evaluation period registered higher well-being levels at the beginning of the semester but a more pronounced decline of it until the semester evaluation period. Conclusion. Based on this research, a relationship between positive well-being, academic assessments, and academic performance is suggested, when evaluating them in a prospective frame.

Electrostatically Tunable Nanomechanical Shallow Arches

KAUST Repository

Kazmi, Syed N. R.

2017-11-03

We report an analytical and experimental study on the tunability of in-plane doubly-clamped nanomechanical arches under varied DC bias conditions at room temperature. For this purpose, silicon based shallow arches are fabricated using standard e-beam lithography and surface nanomachining of a highly conductive device layer on a silicon-on-insulator (SOI) wafer. The experimental results show good agreement with the analytical results with a maximum tunability of 108.14% for 180 nm thick arch with a transduction gap of 1 μm between the beam and the driving/sensing electrodes. The high tunability of shallow arches paves the ways for highly tunable band pass filtering applications in high frequency range.

Simultaneous functional and fixed appliance therapy for growth modification and dental alignment prior to prosthetic habilitation in hypohidrotic ectodermal dysplasia: a clinical report.

Science.gov (United States)

Suri, Sunjay; Carmichael, Robert P; Tompson, Bryan D

2004-11-01

This clinical report describes the simultaneous use of functional and fixed appliances to modify the pattern of dentofacial development and align teeth in preparation for prosthodontic habilitation of a growing child with hypohidrotic ectodermal dysplasia. The treatment objective was to create a more favorable starting point for the prosthodontic phase of habilitation by improving the sagittal and vertical skeletal relationships and facial esthetics. This was accomplished through growth modification with functional appliances conducted simultaneously with eruption of maxillary and mandibular molars, dental arch expansion, alignment, and space management using fixed orthodontic appliances. Orthodontic retention was accomplished by means of removable partial dentures. A second phase of orthodontics conducted closer to the age of skeletal maturation will aim at definitive tooth alignment in preparation for dental implant-supported restorations.

Precast Pearl-Chain concrete arch bridges

DEFF Research Database (Denmark)

Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

2015-01-01

A Pearl-Chain Bridge is a closed-spandrel arch bridge consisting of a number of straight pre-fabricated so called Super-Light Deck elements put together in an arch shape by post-tensioning cables. Several Pearl-Chain arches can be positioned adjacent to each other by a crane to achieve a bridge...... of a desired width. On top of the arch is a filling material to level out the surface of the above road. The filling only transfers vertical loads to the arch. The geometry and material properties of Super-Light Decks are presented, and we refer to several fullscale tests of Pearl-Chain arches where...... the technology was used. We also study other important components and details in the Pearl-Chain Bridge concept and review the effects of different types of loads. A theoretical case study of a circular 30 m span Pearl-Chain Bridge is presented showing the influence of a number of parameters: The number of post...

The relationship between dental caries and carbohydrates intake among preschool-aged children in rural and urban areas

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Rina Putri Noer Fadilah

2017-11-01

Full Text Available Introduction: The prevalence of dental caries among children has increased in the past decades. Dental caries has a multifactorial aetiology, including host (saliva and teeth, microbiology (plaque, substrate (diet, and time. The role of fermentable carbohydrates intake as a risk factor in the initiation and progression of dental caries. The purpose of this study was to determine the relationship between dental caries and carbohydrates intake among preschool-aged children in rural and urban areas of the city of Cimahi, Indonesia. Methods: The method used was an analytical cross-sectional study with pathfinder survey based on the WHO basic methods of oral health surveys. The data were collected through intraoral examination, and nutritional status measurement was done by using food frequency questionnaire. Statistical analysis used was the chi-square test. Results: From the study towards 100 preschool children resulted the prevalence of dental caries in rural and urban area respectively was 96% and 92%. The average value of def-t index in urban area was as much as 8.46 (95% CI:7.00-9.91 and was as much as 7.98 (95% CI:6.50-9.45 in rural area. The average value of sucrose intake frequency in urban area was as much as 237.14 (95% CI:204.95-269.32, whilst in rural area was as much as 177.54 (95% CI:155.66-199.41. There was a relationship between dental caries and carbohydrates intake in the rural and urban area (p < 0,05. Conclusion: There was a relationship between dental caries and carbohydrates intake among preschool-aged children in the rural and urban area of the city of Cimahi, Indonesia.

Imaging findings in the right aortic arch with mirror image branching of arch vessels: An unusual cause of dysphagia

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Guneet Singh

2015-01-01

Full Text Available We report a case of a 72-year-old female with a right aortic arch with mirror-image branching of arch vessels presenting with dysphagia, and characteristic images on barium esophagogram, contrast-enhanced computed tomography scan, and magnetic resonance aortography. Right-sided thoracic aortic arch with mirror-image branching of the brachiocephalic vessels causing dysphagia without associated congenital cardiac anomalies is extremely uncommon. Right-sided aortic arch is a rare congenital abnormality with incidence of 0.05-0.1% in the normal population. Anomalies of great vessels are usually incidental findings, because they are asymptomatic. Right aortic arch infrequently presents with a vascular ring that can cause complete or partial obstruction of the trachea and/or esophagus. The understanding of this arch anomaly is based on Edward′s hypothesis about the double arch system during embryonic developmental.

Concrete-Filled Steel Tube Arch Bridges in China

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Jielian Zheng

2018-02-01

Full Text Available In the past 20 years, great progress has been achieved in China in the construction of concrete-filled steel tube (CFST arch bridges and concrete arch bridges with a CFST skeleton. The span of these bridges has been increasing rapidly, which is rare in the history of bridge development. The large-scale construction of expressways and high-speed railways demands the development of long-span arch bridges, and advances in design and construction techniques have made it possible to construct such bridges. In the present study, the current status, development, and major innovative technologies of CFST arch bridges and concrete arch bridges with a CFST skeleton in China are elaborated. This paper covers the key construction technologies of CFST arch bridges, such as the design, manufacture, and installation of steel tube arch trusses, the preparation and pouring of in-tube concrete, and the construction of the world’s longest CFST arch bridge—the First Hejiang Yangtze River Bridge. The main construction technologies of reinforced concrete arch bridges are also presented, which include cable-stayed fastening-hanging cantilever assembly, adjusting the load by means of stay cables, surrounding the concrete for arch rib pouring, and so forth. In addition, the construction of two CFST skeleton concrete arch bridges—the Guangxi Yongning Yong River Bridge and the Yunnan–Guangxi Railway Nanpan River Bridge—is discussed. CFST arch bridges in China have already gained a world-leading position; with the continuous innovation of key technologies, China will become the new leader in promoting the development of arch bridges. Keywords: Concrete-filled steel tube (CFST arch bridge, Steel-reinforced concrete arch bridge, Cable-stayed fastening-hanging cantilever assembly, Vacuum-assisted pouring in-tube concrete, Adjusting load by stay cables

Relationship between knowledge, attitude, behavior, and self-efficacy on the radiation safety on dental hygienist

International Nuclear Information System (INIS)

Han, Eun Ok; Jun, Sung Hee

2008-01-01

The objective of this study is to draw an educational plant for reducing the probability of troubles caused by radiation for dental hygienists who are the major applicants of radiation equipments used in dental offices. This study investigated the knowledge and self-efficacy, which is the major variable that affects the attitude and behavior, on the radiation safety that is an educational approach. Also, this study obtained following results from a survey for 25 days from June 15, 2008 that was applied for 225 dental hygienists worked at dental offices and clinics in the area of Youngnam in order to verify the relationship between such variables. The average scores for the knowledge, attitude, and behavior were 54.28±16.33, 87.93±9.75, and 59.85±14.76, respectively. Also, the average score of the self-efficacy was 72.88±8.60. In the knowledge level for the radiation safety, ‘a case that prepares personal dosimeters’, ‘a case that establishes protection facilities’, ‘a case that presents 6⁓10 dental hygienists’, ‘a case that presents radiological technologists’, and ‘a case that is a general hospital’ represented high values. In the attitude level for the radiation safety, ‘a case who is a married person’, ‘a case that prepares personal dosimeters’, and ‘a case that is a general hospital’ showed high values. In the behavior level for the radiation safety, ‘a case that shows a career in dental hygienist or radiographic for 6⁓10 years’, ‘a case that attends radiation safety education’, ‘a case that establishes protection facilities’ showed high values. Also, in the self-efficacy level, ‘a case that who has a high education level more than graduate school education’ and ‘a case that establishes protection facilities’ represented high values. In the relationship between the knowledge, attitude, behavior, and self-efficacy for the radiation safety, it showed statistically significant differences in this

Relationship between knowledge, attitude, behavior, and self-efficacy on the radiation safety on dental hygienist

Energy Technology Data Exchange (ETDEWEB)

Han, Eun Ok; Jun, Sung Hee [Daegu Health College, Daegu (Korea, Republic of)

2008-11-15

The objective of this study is to draw an educational plant for reducing the probability of troubles caused by radiation for dental hygienists who are the major applicants of radiation equipments used in dental offices. This study investigated the knowledge and self-efficacy, which is the major variable that affects the attitude and behavior, on the radiation safety that is an educational approach. Also, this study obtained following results from a survey for 25 days from June 15, 2008 that was applied for 225 dental hygienists worked at dental offices and clinics in the area of Youngnam in order to verify the relationship between such variables. The average scores for the knowledge, attitude, and behavior were 54.28±16.33, 87.93±9.75, and 59.85±14.76, respectively. Also, the average score of the self-efficacy was 72.88±8.60. In the knowledge level for the radiation safety, ‘a case that prepares personal dosimeters’, ‘a case that establishes protection facilities’, ‘a case that presents 6⁓10 dental hygienists’, ‘a case that presents radiological technologists’, and ‘a case that is a general hospital’ represented high values. In the attitude level for the radiation safety, ‘a case who is a married person’, ‘a case that prepares personal dosimeters’, and ‘a case that is a general hospital’ showed high values. In the behavior level for the radiation safety, ‘a case that shows a career in dental hygienist or radiographic for 6⁓10 years’, ‘a case that attends radiation safety education’, ‘a case that establishes protection facilities’ showed high values. Also, in the self-efficacy level, ‘a case that who has a high education level more than graduate school education’ and ‘a case that establishes protection facilities’ represented high values. In the relationship between the knowledge, attitude, behavior, and self-efficacy for the radiation safety, it showed statistically significant differences in this

Dental anomalies in 14 patients with IP: clinical and radiological analysis and review.

Science.gov (United States)

Santa-Maria, Fernanda D; Mariath, Luiza Monteavaro; Poziomczyk, Cláudia S; Maahs, Marcia A P; Rosa, Rafael F M; Zen, Paulo R G; Schüller-Faccini, Lavínia; Kiszewski, Ana Elisa

2017-06-01

Current knowledge on dental anomalies in patients with incontinentia pigmenti (IP) has been obtained by examining case reports; however, an overall characterization of such alterations remains lacking. The objective of this study was to determine the frequency, type and location of dental alterations in IP using a case series. Fourteen patients (9 children and 5 adults) with a clinical diagnosis of IP who presented dental anomalies were included in this study. All patients were administered a clinical questionnaire, dental examination and radiological investigation. In the present case series, agenesis of primary dentition was present in 60 % of patients and agenesis of permanent tooth was present in 92.8 % of patients. Most cases were missing at least 6 teeth. Second molar agenesis was present in 13 patients (92.8 %). Anomalies in dental crowns occurred in 71.4 % of cases, and the central incisor was most frequently affected. Two adult patients still had primary teeth. Malocclusion was found in 10 patients (71.4 %). High-arched palate was observed in 7 (50 %) patients. Patients with IP present alterations in both primary and permanent dentition. Because the agenesis of permanent teeth is more common, primary teeth are not always replaced. In addition, the durability of primary dentition appears to be greater in IP. This study shows that patients with IP experience significant loss of teeth, especially in permanent dentition, and have an increased risk of high-arched palate compared to the general population. Prophylactic care of primary teeth in IP is relevant for improving functional and aesthetic outcomes until dental prostheses are implanted.

Riesgos asociados a la pérdida de la longitud del arco dentario en la dentición mixta temprana Risks associated with loss of dental arch length in the early mixed teething

Directory of Open Access Journals (Sweden)

Manuela Ricardo Reyes

2010-09-01

Full Text Available Se realizó un estudio descriptivo y transversal de los 155 niños con pérdida de la longitud del arco dentario en la dentición mixta temprana que acudieron a la consulta de odontología en el área de salud de Genaro Méndez, estado de Táchira, República Bolivariana de Venezuela, desde enero hasta noviembre de 2008, para determinar los riesgos asociados a esta afección. En la serie se obtuvo que la caries dental (36,27 % y las extracciones prematuras (31,37 % constituyeron los riesgos de mayor prevalencia en los niños y niñas de 8 a 9 años. El grupo dentario más afectado fue el posterior (55,48 %; y el diente que más comúnmente perdido por las extracciones prematuras, el segundo molar temporal (42,76 %.A descriptive and cross-sectional study was carried out in 155 children with loss of dental arch length in the early mixed teething, who attended the dental outpatient department in the health area of Genaro Méndez, state of Táchira, Bolivarian Republic of Venezuela, from January to November, 2008, to determine the risks associated with this condition. In the series it was found that the dental decay (36,27 % and early extractions (31,37 % were the most prevalent risks in 8-9 year-old children. The most affected teeth group was the posterior one (55,48 %, and the tooth most commonly lost by early extractions was the second temporal molar (42,76 %.

[Reconstruction and measurement of a digital dental model using grating projection and reverse engineering].

Science.gov (United States)

Zhenzhen, Wang; Yi, Lu; Jun, Song; Jun, Chen; Qin, Zhou

2015-02-01

This work lays the foundation for establishing a digital model database with normal occlusion. A digital dental cast is acquired through grating projection, and model features are measured through reverse engineering. The grating projection system controlled by a computer was projected onto the surface of a normal dental model. Three-dimensional contour data were obtained through multi-angle shooting. A three-dimensional model was constructed, and the model features were analyzed by using reverse engineering. The digital model was compared with the plaster model to determine the accuracy of the measurement system. The structure of three-dimensional reconstruction model was clear. The digital models of two measurements exhibited no significant difference (P > 0.05). When digital and plaster models were measured, we found that the crown length and arch width were not statistically different (P > 0.05), whereas the difference between the crown width and arch length was statistically significant (P model by using the grating projection technique and reverse engineering can be used for dental model measurement in clinic al and scientific research and can provide a scientific method for establishing a digital model database with normal occlusion.

Implant-retained dentures for full-arch rehabilitation: a case report comparing fixed and removable restorations.

Science.gov (United States)

Zafiropoulos, Gregory-George; Hoffman, Oliver

2011-01-01

Dental implants as abutments for full-arch restorations are a well-documented treatment modality. This report presents a case in which the patient was treated initially with fixed restorations supported by either implants or natural teeth and subsequently treated with a removable implant/telescopic crown-supported overdenture. Advantages and disadvantages of each approach are described and discussed. While the fixed restoration resulted in a functionally satisfactory treatment outcome, the patient was displeased with the esthetic appearance. The main concern was the unnaturally long tooth shape necessary to compensate for the insufficient alveolar ridge height. Replacement of the existing restoration with an implant-supported removable overdenture led to a functionally and esthetically acceptable result. When deciding whether to use a fixed or removable implant-supported full-arch restoration, a multitude of factors must be considered. Due to the possible need for additional surgical steps to enhance the esthetic appearance surrounding fixed restorations, removable implant-supported partial dentures often are the better choice.

Methodical Design of Software Architecture Using an Architecture Design Assistant (ArchE)

Science.gov (United States)

2005-04-01

PA 15213-3890 Methodical Design of Software Architecture Using an Architecture Design Assistant (ArchE) Felix Bachmann and Mark Klein Software...DATES COVERED 00-00-2005 to 00-00-2005 4. TITLE AND SUBTITLE Methodical Design of Software Architecture Using an Architecture Design Assistant...important for architecture design – quality requirements and constraints are most important Here’s some evidence: If the only concern is

Accuracy of complete-arch dental impressions: a new method of measuring trueness and precision

OpenAIRE

Ender, Andreas; Mehl, Albert

2013-01-01

STATEMENT OF PROBLEM: A new approach to both 3-dimensional (3D) trueness and precision is necessary to assess the accuracy of intraoral digital impressions and compare them to conventionally acquired impressions. PURPOSE: The purpose of this in vitro study was to evaluate whether a new reference scanner is capable of measuring conventional and digital intraoral complete-arch impressions for 3D accuracy. MATERIAL AND METHODS: A steel reference dentate model was fabricated and measured with a...

Avaliação do espaço adicional requerido no perímetro do arco inferior para o nivelamento da curva de Spee Assessment of the additional lower arch perimeter needed for leveling the curve of Spee

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Marcio José da Silva Campos

2009-08-01

Full Text Available OBJETIVO: determinar o perímetro de arco adicional necessário para o nivelamento da curva de Spee através de uma técnica laboratorial em modelos de estudo. MÉTODOS: foram utilizados 70 modelos inferiores nos quais se mediu a profundidade da curva de Spee e o perímetro do arco (de segundo molar a segundo molar. Nos mesmos modelos, após a simulação do nivelamento da curva de Spee, o perímetro de arco foi novamente avaliado, mantendo sua forma e comprimento. RESULTADOS: foi confirmada a correlação entre a profundidade da curva de Spee e o perímetro de arco adicional, sendo deduzida a fórmula [Paa = 0,21 CSmax - 0,04]. CONCLUSÃO: a técnica proposta permitiu, através da avaliação do perímetro de arco com curva de Spee nivelada, a determinação do espaço disponível para o alinhamento dentário.AIM: To determine the additional arch perimeter needed for leveling the curve of Spee by means of a laboratory technique using dental casts. METHODS: Seventy lower dental models were used for measuring the depth of the curve of Spee and assessing the arch perimeter from second molar to second molar. In these dental casts, after simulation of leveling the curve of Spee, arch perimeter was reevaluated, after maintaining its form and length. RESULTS: The correlation between the depth of the curve of Spee and the additional arch perimeter was ratified, as can be shown by the formula [Paa = 0,21 CSmax - 0,04]. CONCLUSION: The proposed technique allowed, through the assessment of the arch perimeter with the leveled curve of Spee, the determination of the space available for tooth alignment.

Highly Tunable Electrothermally Actuated Arch Resonator

KAUST Repository

Hajjaj, Amal Z.

2016-12-05

This paper demonstrates experimentally, theoretically, and numerically a wide-range tunability of electrothermally actuated MEMS arch beams. The beams are made of silicon and are intentionally fabricated with some curvature as in-plane shallow arches. Analytical results based on the Galerkin discretization of the Euler Bernoulli beam theory are generated and compared to the experimental data and results of a multi-physics finite-element model. A good agreement is found among all the results. The electrothermal voltage is applied between the anchors of the clamped-clamped MEMS arch beam, generating a current that passes through the MEMS arch beam and controls its axial stress caused by thermal expansion. When the electrothermal voltage increases, the compressive stress increases inside the arch beam. This leads to increase in its curvature, thereby increases the resonance frequencies of the structure. We show here that the first resonance frequency can increase up to twice its initial value. We show also that after some electro-thermal voltage load, the third resonance frequency starts to become more sensitive to the axial thermal stress, while the first resonance frequency becomes less sensitive. These results can be used as guidelines to utilize arches as wide-range tunable resonators.

Applications of Nanomaterials in Dental Science: A Review.

Science.gov (United States)

Sharan, Jitendra; Singh, Shivani; Lale, Shantanu V; Mishra, Monu; Koul, Veena; Kharbanda, P

2017-04-01

Nanotechnology has revolutionized health care industry in a large scale and its applications are a boon to modern medicine and dental science. It is expected to pervade and further revolutionize the art and science of dentistry and may well have important applications spanning all the aspects of oral diseases, diagnosis, prevention and treatment. Materials science in dentistry has embraced the technology to produce nanomaterials that are being used in caries inhibitors, antimicrobial resins, hard tissue remineralizing agents, targeted drug delivery, scaffolds, bio-membranes, nanocrystalline hydroxyl apatite, restorative cements, adhesion promoters and boosters, bioactive glass, tissue conditioners, reinforced methacrylate resins, root canal disinfectants, friction free orthodontic arch wires and nano composites life. These upcoming technologies have potential to bring about significant benefits in the form of improvement in dental science and to society. The present review presents the latest recent developments in this interdisciplinary field bridging nanotechnology and dental science.

Electrothermally Tunable Arch Resonator

KAUST Repository

Hajjaj, Amal Z.

2017-03-18

This paper demonstrates experimentally, theoretically, and numerically a wide-range tunability of electrothermally actuated microelectromechanical arch beams. The beams are made of silicon and are intentionally fabricated with some curvature as in-plane shallow arches. An electrothermal voltage is applied between the anchors of the beam generating a current that controls the axial stress caused by thermal expansion. When the electrothermal voltage increases, the compressive stress increases inside the arch beam. This leads to an increase in its curvature, thereby increasing its resonance frequencies. We show here that the first resonance frequency can increase monotonically up to twice its initial value. We show also that after some electrothermal voltage load, the third resonance frequency starts to become more sensitive to the axial thermal stress, while the first resonance frequency becomes less sensitive. These results can be used as guidelines to utilize arches as wide-range tunable resonators. Analytical results based on the nonlinear Euler Bernoulli beam theory are generated and compared with the experimental data and the results of a multi-physics finite-element model. A good agreement is found among all the results. [2016-0291

Standardizing foot-type classification using arch index values.

Science.gov (United States)

Wong, Christopher Kevin; Weil, Rich; de Boer, Emily

2012-01-01

The lack of a reliable classification standard for foot type makes drawing conclusions from existing research and clinical decisions difficult, since different foot types may move and respond to treatment differently. The purpose of this study was to determine interrater agreement for foot-type classification based on photo-box-derived arch index values. For this correlational study with two raters, a sample of 11 healthy volunteers with normal to obese body mass indices was recruited from both a community weight-loss programme and a programme in physical therapy. Arch index was calculated using AutoCAD software from footprint photographs obtained via mirrored photo-box. Classification as high-arched, normal, or low-arched foot type was based on arch index values. Reliability of the arch index was determined with intra-class correlations; agreement on foot-type classification was determined using quadratic weighted kappa (κw). Average arch index was 0.215 for one tester and 0.219 for the second tester, with an overall range of 0.017 to 0.370. Both testers classified 6 feet as low-arched, 9 feet as normal, and 7 feet as high-arched. Interrater reliability for the arch index was ICC=0.90; interrater agreement for foot-type classification was κw=0.923. Classification of foot type based on arch index values derived from plantar footprint photographs obtained via mirrored photo-box showed excellent reliability in people with varying BMI. Foot-type classification may help clinicians and researchers subdivide sample populations to better differentiate mobility, gait, or treatment effects among foot types.

Standardizing Foot-Type Classification Using Arch Index Values

Science.gov (United States)

Weil, Rich; de Boer, Emily

2012-01-01

ABSTRACT Purpose: The lack of a reliable classification standard for foot type makes drawing conclusions from existing research and clinical decisions difficult, since different foot types may move and respond to treatment differently. The purpose of this study was to determine interrater agreement for foot-type classification based on photo-box-derived arch index values. Method: For this correlational study with two raters, a sample of 11 healthy volunteers with normal to obese body mass indices was recruited from both a community weight-loss programme and a programme in physical therapy. Arch index was calculated using AutoCAD software from footprint photographs obtained via mirrored photo-box. Classification as high-arched, normal, or low-arched foot type was based on arch index values. Reliability of the arch index was determined with intra-class correlations; agreement on foot-type classification was determined using quadratic weighted kappa (κw). Results: Average arch index was 0.215 for one tester and 0.219 for the second tester, with an overall range of 0.017 to 0.370. Both testers classified 6 feet as low-arched, 9 feet as normal, and 7 feet as high-arched. Interrater reliability for the arch index was ICC=0.90; interrater agreement for foot-type classification was κw=0.923. Conclusions: Classification of foot type based on arch index values derived from plantar footprint photographs obtained via mirrored photo-box showed excellent reliability in people with varying BMI. Foot-type classification may help clinicians and researchers subdivide sample populations to better differentiate mobility, gait, or treatment effects among foot types. PMID:23729964

Assembly and lifting of Pearl-Chain arches

DEFF Research Database (Denmark)

Halding, Philip Skov; Hertz, Kristian Dahl; Viebæk, N.E.

2015-01-01

Pearl-Chain arches were invented at the Technical University of Denmark in cooporation with the company Abeo A/S. The system uses specially designed, pre-fabricated concrete elements that are post-tensioned together into an arch shape, which is then lifted into place. The arches can be used both ...

The Relationship between Sugar-Containing Methadone and Dental Caries: A Systematic Review

Science.gov (United States)

Tripathee, Sheela; Akbar, Tahira; Richards, Derek; Themessl-Huber, Markus; Freeman, Ruth

2013-01-01

Objectives: To review the evidence of a relationship between sugar-containing methadone and dental caries. Data sources: A systematic search of Cochrane Library, PubMed, PsychINFO, EMBASE, MEDLINE, Current Controlled Trials, WHO, OHRN, SIGLE and ERIC databases was conducted from January 1978 up to June 2010. Study selection: Articles were assessed…

Assessment of complete unilateral cleft lip and palate treatment outcome using EUROCRAN index and associated factors.

Science.gov (United States)

Arshad, Anas Imran; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli

2017-09-01

Assessment of treatment outcome is the only non-invasive approach to identify the effects of cleft lip and palate repair and modify management accordingly. Here the aim is to assess the outcome of complete unilateral cleft lip and palate (CUCLP) patients using EUROCRAN index and to check whether there are any factors associated with the treatment outcome. It is a retrospective cross sectional study. Dental models were collected from archives of two cleft referral centers in Pakistan. Five blinded examiners scored 101 models twice at two week interval. The primary outcome was mean EUROCRAN scores based on dental arch relationships and palatal surface morphology. A mean(SD) score of 2.72 (0.76) and 2.20 (0.73) was determined based on dental arch relationships and palatal surface morphology, respectively. According to the final logistic regression model, modified Millard technique (cheiloplasty) and Veau-Wardill-Kilners' method (palatoplasty) had higher odds of producing unfavorable treatment outcome. Present study determined a fair and a fair to poor treatment outcome based on dental arch relationships and palatal surface morphology, respectively. Our study suggests a significant association between treatment outcome and primary surgical techniques for lip and palate. These findings could warrant a modification of management protocols to ensure improvement in future cleft outcomes. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of dental technician disparities on the 3-dimensional accuracy of definitive casts.

Science.gov (United States)

Emir, Faruk; Piskin, Bulent; Sipahi, Cumhur

2017-03-01

Studies that evaluated the effect of dental technician disparities on the accuracy of presectioned and postsectioned definitive casts are lacking. The purpose of this in vitro study was to evaluate the accuracy of presectioned and postsectioned definitive casts fabricated by different dental technicians by using a 3-dimensional computer-aided measurement method. An arch-shaped metal master model consisting of 5 abutments resembling prepared mandibular incisors, canines, and first molars and with a 6-degree total angle of convergence was designed and fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM) technology. Complete arch impressions were made (N=110) from the master model, using polyvinyl siloxane (PVS) and delivered to 11 dental technicians. Each technician fabricated 10 definitive casts with dental stone, and the obtained casts were numbered. All casts were sectioned, and removable dies were obtained. The master model and the presectioned and postsectioned definitive casts were digitized with an extraoral scanner, and the virtual master model and virtual presectioned and postsectioned definitive casts were obtained. All definitive casts were compared with the master model by using computer-aided measurements, and the 3-dimensional accuracy of the definitive casts was determined with best fit alignment and represented in color-coded maps. Differences were analyzed using univariate analyses of variance, and the Tukey honest significant differences post hoc tests were used for multiple comparisons (α=.05). The accuracy of presectioned and postsectioned definitive casts was significantly affected by dental technician disparities (Ptechnician differences. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Effective dose comparison between protocols stitched and usual protocols in dental cone beam CT for complete arcade

International Nuclear Information System (INIS)

Soares, M. R.; Maia, A. F.; Batista, W. O. G.; Lara, P. A.

2014-08-01

To visualization a complete dental radiology dental lives together with two separate proposals: [1] protocols diameter encompassing the entire arch (single) or [2] protocol with multiple fields of view (Fov) which together encompass the entire arch (stitched Fov s). The objective of this study is to evaluate effective dose values in examination protocols for all dental arcade available in different outfits with these two options. For this, a female anthropomorphic phantom manufactured by Radiology Support Devices twenty six thermoluminescent dosimeters inserted in relevant bodies and positions was used. Irradiate the simulator in the clinical conditions. The protocols were averaged and compared: [a] 14.0 cm x 8.5 cm and [b] 8.5 cm x 8.5 cm (Gendex Tomography GXCB 500), [c] protocol stitched for jaw combination of three volumes of 5.0 cm x 3.7 cm (Kodak 9000 3D scanner) [d] protocol stitched Fov s 5.0 cm x 8.0 cm (Planmeca Pro Max 3D) and [e] single technical Fov 14 cm x 8 cm (i-CAT Classical). Our results for the effective dose were: a range between 43.1 and 111.1 micro Sv for technical single Fov and 44.5 and 236.2 for technical stitched Fov s. The protocol presented the highest estimated effective dose was [d] and showed that lowest index was registered [a]. These results demonstrate that the protocol stitched Fov generated in Kodak 9000 3D machine applied the upper dental arch has practically equal value effective dose obtained by protocol extended diameter of, [a], which evaluates in a single image upper and lower arcade. It also demonstrates that the protocol [d] gives an estimate of five times higher than the protocol [a]. Thus, we conclude that in practical terms the protocol [c] stitched Fov s, not presents dosimetric advantages over other protocols. (Author)

Effective dose comparison between protocols stitched and usual protocols in dental cone beam CT for complete arcade

Energy Technology Data Exchange (ETDEWEB)

Soares, M. R.; Maia, A. F. [Universidade Federal de Sergipe, Departamento de Fisica, Cidade Universitaria Prof. Jose Aloisio de Campos, Marechal Rondon s/n, Jardim Rosa Elze, 49-100000 Sao Cristovao, Sergipe (Brazil); Batista, W. O. G. [Instituto Federal da Bahia, Rua Emidio dos Santos s/n, Barbalho, Salvador, 40301015 Bahia (Brazil); Lara, P. A., E-mail: wilsonottobatista@gmail.com [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

2014-08-15

To visualization a complete dental radiology dental lives together with two separate proposals: [1] protocols diameter encompassing the entire arch (single) or [2] protocol with multiple fields of view (Fov) which together encompass the entire arch (stitched Fov s). The objective of this study is to evaluate effective dose values in examination protocols for all dental arcade available in different outfits with these two options. For this, a female anthropomorphic phantom manufactured by Radiology Support Devices twenty six thermoluminescent dosimeters inserted in relevant bodies and positions was used. Irradiate the simulator in the clinical conditions. The protocols were averaged and compared: [a] 14.0 cm x 8.5 cm and [b] 8.5 cm x 8.5 cm (Gendex Tomography GXCB 500), [c] protocol stitched for jaw combination of three volumes of 5.0 cm x 3.7 cm (Kodak 9000 3D scanner) [d] protocol stitched Fov s 5.0 cm x 8.0 cm (Planmeca Pro Max 3D) and [e] single technical Fov 14 cm x 8 cm (i-CAT Classical). Our results for the effective dose were: a range between 43.1 and 111.1 micro Sv for technical single Fov and 44.5 and 236.2 for technical stitched Fov s. The protocol presented the highest estimated effective dose was [d] and showed that lowest index was registered [a]. These results demonstrate that the protocol stitched Fov generated in Kodak 9000 3D machine applied the upper dental arch has practically equal value effective dose obtained by protocol extended diameter of, [a], which evaluates in a single image upper and lower arcade. It also demonstrates that the protocol [d] gives an estimate of five times higher than the protocol [a]. Thus, we conclude that in practical terms the protocol [c] stitched Fov s, not presents dosimetric advantages over other protocols. (Author)

Occlusion and Temporomandibular Function among Subjects with Mandibular Distal Extension Removable Partial Dentures

Science.gov (United States)

Creugers, N. H. J.; Witter, D. J.; Van 't Spijker, A.; Gerritsen, A. E.; Kreulen, C. M.

2010-01-01

Objective. To quantify effects on occlusion and temporomandibular function of mandibular distal extension removable partial dentures in shortened dental arches. Methods. Subjects wearing mandibular extension removable partial dentures (n = 25) were compared with subjects with shortened dental arches without extension (n = 74) and with subjects who had worn a mandibular extension removable partial denture in the past (n = 19). Subjects with complete dentitions (n = 72) were controls. Data were collected at baseline and at 3-, 6-, and 9-year observations. Results. Occlusal activity in terms of reported awareness of bruxism and occlusal tooth wear of lower anterior teeth did not differ significantly between the groups. In contrast, occlusal tooth wear of premolars in shortened dental arches with or without extension dentures was significantly higher than in the controls. Differences amongst groups with respect to signs and symptoms related to temporomandibular disorders were not found. Occlusal support of the dentures did not influence anterior spatial relationship. Occlusal contacts of the denture teeth decreased from 70% for second premolars via 50% for first molars, to 30% for second molars. Conclusions. Mandibular distal extension removable partial dentures in moderate shortened dental arches had no effects on occlusion and temporomandibular function. PMID:20671961

Some insights for a relationship marketing model integrating SERVQUAL and customer loyalty in dental clinics

OpenAIRE

Vargas Perez, Ana Maria; Grijalvo Martin, Maria Mercedes; Mercado Idoeta, Carmelo

2012-01-01

The demand of new services, the emergence of new business models, insufficient innovation, underestimation of customer loyalty and reluctance to adopt new management are evidence of the deficiencies and the lack of research about the relations between patients and dental clinics. In this article we propose the structure of a model of Relationship Marketing (RM) in the dental clinic that integrates information from SERVQUAL, Customer Loyalty (CL) and activities of RM and combines the vision of...

Relationship between Risk Behavior for Eating Disorders and Dental Caries and Dental Erosion.

Science.gov (United States)

Brandt, Lorenna Mendes Temóteo; Fernandes, Liege Helena Freitas; Aragão, Amanda Silva; Aguiar, Yêska Paola Costa; Auad, Sheyla Márcia; de Castro, Ricardo Dias; Cavalcanti, Sérgio D'Ávila Lins Bezerra; Cavalcanti, Alessandro Leite

2017-01-01

The aim of this study was to evaluate whether there is an association between risk behavior for eating disorders (EDs) and dental erosion and caries. A controlled cross-sectional study was conducted in Brazil, involving 850 randomly selected female adolescents. After evaluating risk behavior for eating disorders through the Bulimic Investigatory Test of Edinburgh, 12 adolescents were identified with severe risk behavior for EDs and matched to 48 adolescents without such risk. Dental examinations, anthropometric measurements, and eating habits and oral hygiene were performed. Adolescents with high severity eating disorder condition were not more likely to show dental caries ( p = 0.329; OR = 2.2, 95% CI: 0.35-13.72) or dental erosion ( p = 0.590; OR = 2.33; 95% CI: 0.56-9.70). Adolescents with high body mass index (BMI) were five times more likely to have high severity eating disorder condition ( p = 0.031; OR = 5.1; 95% CI: 1.61-23.07). Therefore, high severity risk behavior for EDs was not significantly associated with dental caries and dental erosion. However, high BMI was a risk factor for developing eating disorders and should be an alert for individuals with this condition.

Anatomic variations of the branches of the aortic arch in a Peruvian population.

Science.gov (United States)

Huapaya, Julio Arturo; Chávez-Trujillo, Kristhy; Trelles, Miguel; Dueñas Carbajal, Roy; Ferrandiz Espadin, Renato

2015-07-31

Previous publications from two countries in South America found one anatomical variation not previously reported in the rest of the world, which in turn give some clues with regard to a racial difference. The objective of the present study is to describe variations in the anatomical distribution of the branches of the aortic arch in a Peruvian population. To describe variations in the anatomical distribution of the branches of the aortic arch in a Peruvian population. A descriptive study of patients who underwent a tomography angiography of the aorta was performed. We analyzed the reports that showed the description of the variations of the branches of the aortic arch based on the eight types currently described in the literature. From 361 analyzed reports, 282 patients (78.12%) had a normal aortic arch configuration (type I; aortic arch gives rise to the brachiocephalic trunk, left common carotid and left subclavian arteries); followed by type II (left common carotid artery as a branch of the aorta) with 41 patients (11.36%); and type IX (common ostium for the brachiocephalic trunk and the left common carotid artery) with 25 patients (6.93%). The latter and two other types are new variations. Aortic Arch Type I, Type II and Type IX were the most frequent variations in this Peruvian study. Additionally, we also found two more new types that have not been previously described in the literature. Further investigation regarding these variations is needed in order to assess a racial factor in South America and possible relationships with clinical or surgical events.

Agreement in the determination of preformed wire shape templates on plaster models and customized digital arch form diagrams on digital models.

Science.gov (United States)

Camardella, Leonardo Tavares; Sá, Maiara da Silva Bezerra; Guimarães, Luciana Campos; Vilella, Beatriz de Souza; Vilella, Oswaldo de Vasconcellos

2018-03-01

The aim of this study was to verify the accuracy of preformed wire shape templates on plaster models and those of customized digital arch form diagrams on digital models. Twenty pairs of dental plaster models were randomly selected from the archives of the Department of Orthodontics of Federal Fluminense University, Niterói, Rio de Janeiro, Brazil. All plaster model samples were scanned in a plaster model scanner to create the respective digital models. Three examiners defined the arch form on the mandibular arch of these models by selecting the ideal preformed wire shape template on each plaster model or by making a customized digital arch form on the digital models using a digital arch form customization tool. These 2 arch forms were superimposed by the best-fit method. The greatest differences in the 6 regions on the superimposed arches were evaluated. Each examiner presented a descriptive analysis with the means, standard deviation, and minimum and maximum intervals of the differences on the superimpositions. Intraclass correlation coefficient and paired t tests were used to evaluate the accuracy of the superimpositions. Among the 6 regions analyzed in the superimpositions, the largest differences in the anterior and premolar regions were considered clinically insignificant, whereas the largest differences in the right molar region, especially the second molar area, were considered clinically significant by all 3 examiners. The intraclass correlation coefficients showed a weak correlation in the premolar region and moderate correlations in the anterior and molar regions. The paired t test showed statistically significant differences in the left anterior and premolar regions. The superimpositions between the arch forms on plaster and digital models were considered accurate, and the differences were not clinically significant, with the exception of the second molar area. Despite the favorable results, the requirement of correcting some software problems may

Semi-parametric estimation for ARCH models

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Raed Alzghool

2018-03-01

Full Text Available In this paper, we conduct semi-parametric estimation for autoregressive conditional heteroscedasticity (ARCH model with Quasi likelihood (QL and Asymptotic Quasi-likelihood (AQL estimation methods. The QL approach relaxes the distributional assumptions of ARCH processes. The AQL technique is obtained from the QL method when the process conditional variance is unknown. We present an application of the methods to a daily exchange rate series. Keywords: ARCH model, Quasi likelihood (QL, Asymptotic Quasi-likelihood (AQL, Martingale difference, Kernel estimator

Dental Calculus Arrest of Dental Caries.

Science.gov (United States)

Keyes, Paul H; Rams, Thomas E

An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. These observations further document the potential protective effects of dental calculus mineralization against dental caries.

Dental Calculus Arrest of Dental Caries

Science.gov (United States)

Keyes, Paul H.; Rams, Thomas E.

2016-01-01

Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

Relationship between Child and Parental Dental Anxiety with Child's Psychological Functioning and Behavior during the Administration of Local Anesthesia.

Science.gov (United States)

Boka, Vasiliki; Arapostathis, Konstantinos; Kotsanos, Nikolaos; Karagiannis, Vassilis; van Loveren, Cor; Veerkamp, Jaap

2016-01-01

The aims of this study were to determine: 1) the relationship between children's psychological functioning, dental anxiety and cooperative behavior before and during local anesthesia, 2) the relationship of parental dental anxiety with all the above child characteristics. There was a convenient sample of 100 children (4-12 years). Child dental anxiety and psychological functioning were measured using the "Children's Fear Survey Schedule" (CFSS-DS) and the "Strengths and Difficulties Questionnaire" (SDQ) respectively. Parental dental anxiety was measured using the "Modified Dental Anxiety Scale" (MDAS). All questionnaires were completed by parents. Before and during local anesthesia, the child behavior was scored by one experienced examiner, using the Venham scale. Non-parametric tests and correlations (Mann-Whitney, Spearman's rho) were used for the analysis. The mean SDQ score was 10±5.6 for boys (n=60) and 8.3±4.8 for girls (n=40) (p=0.038), but there was no correlation with children's age. The mean CFSS-DS score was 33.1±11.86 and there was no correlation with age or gender. Children with higher levels in the pro-social subscale of the SDQ had significantly less anxiety and better behavior before local anesthesia. Higher mean CFSS-DS scores were significantly associated with uncooperative behavior during local anesthesia (p=0.04). There was no correlation between parents' and their children's dental anxiety, psychological functioning and behavior. 46% of the children had previous dental experience in the last 6 months. As time since the last dental treatment increased, an improvement was found in children's behavior during local anesthesia. Child psychological functioning was related to dental anxiety and behavior during dental appointment involving local anesthesia.

Maxillary arch rehabilitation using implant-supported computer-assisted design-computer-assisted manufacturing-milled titanium framework

Directory of Open Access Journals (Sweden)

Tulika S Khanna

2017-01-01

Full Text Available Esthetic and functional rehabilitation of completely edentulous maxillary arch with fixed implant supported prosthesis is a challenging task. Newer technologies such as computer assisted design computer assisted manufacturing (CAD CAM and cone beam conventional tomography play an important role in achieving predictable results. Full mouth porcelain fused to metal (PFM individual crowns on CAD CAM milled titanium framework provides positive esthetic and functional outcome. This is a case report of rehabilitation of partially edentulous maxillary arch patient. Staged rehabilitation of this patient was planned. In the first stage, root canal treatment of key abutment teeth was done, nonsalvageable teeth were removed, and immediate interim overdenture was provided. In the second stage, five Nobel Biocare dental implants were placed. After integration impressions were made, CAD CAM milled titanium bar was fabricated. Individual PFM crowns were made and cemented. This method gives better esthetic compared to acrylic fused to metal hybrid prosthesis with the advantage of retrievability just like screw retained prosthesis. Hence, this technique is good for rehabilitation of patients with high esthetic demands.

Nonlinear Dynamics of Electrostatically Actuated MEMS Arches

KAUST Repository

Al Hennawi, Qais M.

2015-05-01

In this thesis, we present theoretical and experimental investigation into the nonlinear statics and dynamics of clamped-clamped in-plane MEMS arches when excited by an electrostatic force. Theoretically, we first solve the equation of motion using a multi- mode Galarkin Reduced Order Model (ROM). We investigate the static response of the arch experimentally where we show several jumps due to the snap-through instability. Experimentally, a case study of in-plane silicon micromachined arch is studied and its mechanical behavior is measured using optical techniques. We develop an algorithm to extract various parameters that are needed to model the arch, such as the induced axial force, the modulus of elasticity, and the initially induced initial rise. After that, we excite the arch by a DC electrostatic force superimposed to an AC harmonic load. A softening spring behavior is observed when the excitation is close to the first resonance frequency due to the quadratic nonlinearity coming from the arch geometry and the electrostatic force. Also, a hardening spring behavior is observed when the excitation is close to the third (second symmetric) resonance frequency due to the cubic nonlinearity coming from mid-plane stretching. Then, we excite the arch by an electric load of two AC frequency components, where we report a combination resonance of the summed type. Agreement is reported among the theoretical and experimental work.

Tracheal compression due to an elongated aortic arch in patients with congenital heart disease: evaluation using multidetector-row CT

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Noriko; Hayabuchi, Yasunobu; Inoue, Miki; Sakata, Miho; Nabo, Manal Mohamed Helmy; Nakagawa, Ryuji; Saijo, Takahiko; Kagami, Shoji [University of Tokushima, Department of Pediatrics, Tokushima (Japan)

2009-10-15

The airway can become obstructed as a result of compression by an elongated aortic arch. In this study we evaluated tracheal compression using multidetector-row CT in patients with congenital heart disease and an elongated aortic arch. The trachea was measured at the level of the aortic arch in 205 children and young adults and then the severity of tracheal compression was determined by measuring the tracheal diameter ratio (short axis diameter/long axis diameter). Patients were divided as follows: group I (normal aortic arch; n=166), group II (transversely running aortic arch; n=22), and group III (elongated aortic arch; n=17). From the viewpoint of the relationship of the great arteries, group II had D-malposition, and group III had L-malposition. Age, height, weight and body surface area were significantly correlated with the short and long axis diameter in group I. There was a negative correlation between tracheal diameter ratio and the physical size parameters. The tracheal diameter ratio in group III was 0.50{+-}0.13, which was significantly lower than in groups I and II (P<0.01 and 0.05, respectively). Even apparently asymptomatic patients with an elongated aortic arch can have tracheal compression. An elongated aortic arch may be a useful predictor of tracheal compression. (orig.)

Highly tunable NEMS shallow arches

KAUST Repository

Kazmi, Syed N. R.

2017-11-30

We report highly tunable nanoelectromechanical systems NEMS shallow arches under dc excitation voltages. Silicon based in-plane doubly clamped bridges, slightly curved as shallow arches, are fabricated using standard electron beam lithography and surface nanomachining of a highly conductive device layer on a silicon-on-insulator wafer. By designing the structures to have gap to thickness ratio of more than four, the mid-plane stretching of the nano arches is maximized such that an increase in the dc bias voltage will result into continuous increase in the resonance frequency of the resonators to wide ranges. This is confirmed analytically based on a nonlinear beam model. The experimental results are found to be in good agreement with that of the results from developed analytical model. A maximum tunability of 108.14% for a 180 nm thick arch with an initially designed gap of 1 μm between the beam and the driving/sensing electrodes is achieved. Furthermore, a tunable narrow bandpass filter is demonstrated, which opens up opportunities for designing such structures as filtering elements in high frequency ranges.

Mycotic Aneurysm of the Aortic Arch

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Ji Hye Seo

2014-08-01

Full Text Available A mycotic aneurysm of the thoracic aorta is rare. We report a case of mycotic aneurysm that developed in the aortic arch. An 86-year-old man was admitted with fever and general weakness. Blood culture yielded methicillin-resistant Staphylococcus aureus. Chest X-ray showed an enlarged aortic arch, and computed tomography scan revealed an aneurysm in the aortic arch. The patient was treated only with antibiotics and not surgically. The size of the aneurysm increased rapidly, resulting in bronchial obstruction and superimposed pneumonia. The patient died of respiratory failure.

An epidemiological study of malocclusion and occlusal traits related to different stages of dental development

Directory of Open Access Journals (Sweden)

Lejla Redžepagić Vražalica

2017-04-01

Full Text Available Abstract Introduction: Various types of malocclusions present one of the most common dental problems of today’s population. Planning the implementation of orthodontic therapy, especially preventive and interceptive measures is one of many activities of public sector health, and it requires information regarding the prevalence of malocclusion in different parts of our country. Aim: The aim of this study was to determine the prevalence of malocclusion of preschool and school children in the city of Sarajevo. Materials and methods: This study was comprised of 373 children out of which 200 preschool and school children were included in the final sample according to the inclusion and exclusion criteria for participation. 100 children were five-year-olds with complete deciduous dentition, and 100 children were 14-year-olds with permanent dentition. The examined variables in the study were: dental status and existence of caries, overjet, depth of overbite, a presence of premature contacts, a presence of diastemas, crowding of teeth in the dental arch (for 14-year-olds and rotation of teeth in the dental arch (for 14-year-olds. Results: The prevalence of malocclusion was 58% in the group of preschool children and 83% in the group of school children. Conclusion: Results of this study demonstrate a need for the implementation of preventive and interceptive orthodontic methods in primary health care, which would reduce the need for expensive and long term orthodontic therapy.

Fragile X syndrome: panoramic radiographic evaluation of dental anomalies, dental mineralization stage, and mandibular angle

Directory of Open Access Journals (Sweden)

Aida Sabbagh-Haddad

Full Text Available ABSTRACT Fragile X syndrome (FXS is a disorder linked to the chromosome X long arm (Xq27.3, which is identified by a constriction named fragile site. It determines various changes, such as behavioral or emotional problems, learning difficulties, and intellectual disabilities. Craniofacial abnormalities such as elongated and narrow face, prominent forehead, broad nose, large and prominent ear pavilions, strabismus, and myopia are frequent characteristics. Regarding the oral aspects, deep and high-arched palate, mandibular prognathism, and malocclusion are also observed. Objective: The purpose of this study was to evaluate the dental radiographic characteristics as described in 40 records of patients with panoramic radiography. Material and Methods: The patients were in the range of 6–17 years old, and were divided into two groups (20 subjects who were compatible with the normality standard and 20 individuals diagnosed with the FXS, which were matched for gender and age. Analysis of the panoramic radiographic examination involved the evaluation of dental mineralization stage, mandibular angle size, and presence of dental anomalies in both deciduous and permanent dentitions. Results: The results of radiographic evaluation demonstrated that the chronology of tooth eruption of all third and second lower molars is anticipated in individuals with FXS (p<0.05. In this group, supernumerary deciduous teeth (2.83%, giroversion of permanent teeth (2.31%, and partial anodontia (1.82% were the most frequent dental anomalies. In addition, an increase was observed in the mandibular angle size in the FXS group (p<0.05. Conclusion: We conclude that knowledge of dental radiographic changes is of great importance for dental surgeons to plan the treatment of these individuals.

The relationship between radiological features and clinical manifestation and dental expenses of keratocystic odontogenic tumor

International Nuclear Information System (INIS)

Min, Jung Hyun; Huh, Kyung Heo; Heo, Min Suk; Choi, Soon Chul; Lee, Sam Sun; Bae, Kwang Hak; Choi, Jin Woo

2013-01-01

This study was performed to identify correlations between keratocystic odontogenic tumor (KCOT) data from CT sections, and data on the KCOT clinical manifestation and resulting dental expenses. Following local Institutional Review Board (IRB) approval, a seven-years of retrospective study was performed regarding patients with KCOTs treated at the Seoul National University Dental Hospital. A total of 180 KCOT were included in this study. The following information was collected: age, gender, location and size of the lesion, radiological features, surgical treatment provided and dental expenses. There was no significant association between the size of the KCOT and age, gender, and presenting preoperative symptoms. In both jaws, it was unusual to find KCOTs under 10 mm. The correlation between the number of teeth removed and the size of the KCOT in the tooth bearing area was statistically significant in the mandible, whereas in the maxilla, no significant relationship was found. Dental expenses compared with the size of the KCOT were found to be significant in both jaws. The size of KCOT was associated with a significant increase in dental expenses for both jaws and the number of teeth removed from the mandible. These findings emphasize the importance of routine examinations and early detection of lesions, which in turn helps preserving anatomical structures and reducing dental expenses.

The relationship between radiological features and clinical manifestation and dental expenses of keratocystic odontogenic tumor

Energy Technology Data Exchange (ETDEWEB)

Min, Jung Hyun; Huh, Kyung Heo; Heo, Min Suk; Choi, Soon Chul; Lee, Sam Sun; Bae, Kwang Hak [Dept. of School of Dentistry, Seoul National University, Seoul (Korea, Republic of); Choi, Jin Woo [Dept. of Oral and Maxillofacial Radiology, Dankook University College of Dentistry, Cheonan (Korea, Republic of)

2013-06-15

This study was performed to identify correlations between keratocystic odontogenic tumor (KCOT) data from CT sections, and data on the KCOT clinical manifestation and resulting dental expenses. Following local Institutional Review Board (IRB) approval, a seven-years of retrospective study was performed regarding patients with KCOTs treated at the Seoul National University Dental Hospital. A total of 180 KCOT were included in this study. The following information was collected: age, gender, location and size of the lesion, radiological features, surgical treatment provided and dental expenses. There was no significant association between the size of the KCOT and age, gender, and presenting preoperative symptoms. In both jaws, it was unusual to find KCOTs under 10 mm. The correlation between the number of teeth removed and the size of the KCOT in the tooth bearing area was statistically significant in the mandible, whereas in the maxilla, no significant relationship was found. Dental expenses compared with the size of the KCOT were found to be significant in both jaws. The size of KCOT was associated with a significant increase in dental expenses for both jaws and the number of teeth removed from the mandible. These findings emphasize the importance of routine examinations and early detection of lesions, which in turn helps preserving anatomical structures and reducing dental expenses.

On dental caries and dental erosion in Swedish young adults.

Science.gov (United States)

Isaksson, Helén

2013-01-01

All children in Sweden are entitled to regular, free dental care up to 20 years of age. While dental caries generally continues to decline, still there is a pronounced skewness in caries prevalence. Furthermore, the reported increase in dental erosion in young adults is cause for concern. The aim was to study the prevalence of dental caries and dental erosion in a cohort of Swedish 20 year-olds, with special reference to the influence of previous caries experience and lifestyle as well as parental, socioeconomic and psychosocial factors. The study was prospective, longitudinal and cross-sectional in design and based on registration of caries lesions, dental erosion, body adiposity status, saliva sampling, interviews, and questionnaires at 20 years of age. Data were available for the same cohort at 1, 3, 6 and 15 years of age. 499 subjects (74 percent of the original cohort) were included. Five individuals were subsequently excluded, leaving a final sample of 494. 74 percent of the subjects had initial and/or manifest caries lesions and/or restorations. The mean number of DimFS was 5.8 and the mean number of DmFS on occlusal surfaces of molars was 1.1. There was a strong relationship between caries activity at 3 and 6 years of age and approximal caries prevalence in premolars and molars at 20 years of age. Overweight/obese individuals had significantly higher caries prevalence than normal weight individuals. Parental, socioeconomic and psychosocial factors during infancy were related to approximal caries at age 20. Dental erosion was found in 75 percent of the individuals: 18 percent of these had extensive erosion. There was a significant association between caries and dental erosion. A relationship was found between dental erosion and lifestyle factors and overweight/obesity. There is a strong relationship between caries prevalence at age 20 and caries experience in early childhood. Young adults show a high prevalence of dental erosion, but the severity is

Relationship between Learning Style and Academic Status of Babol Dental Students

Science.gov (United States)

Nasiri, Zahra; Gharekhani, Samane; Ghasempour, Maryam

2016-01-01

Introduction Identifying and employing students’ learning styles could play an important role in selecting appropriate teaching methods in order to improve education. The aim of this study was to determine the relationship between the students’ final exam scores and the learning style preferences of dental students at Babol University of Medical Sciences. Methods This cross-sectional study was conducted on 88 dental students studying in their fourth, fifth, and sixth years using the visual–aural–reading/writing–kinesthetic (VARK) learning styles’ questionnaire. The data were analyzed with IBM SPSS, version 21, using the chi-squared test and the t-test. Results Of the 88 participants who responded to the questionnaire, 87 preferred multimodal learning styles. There was no significant difference between the mean of the final exam scores in students who did and did not prefer the aural learning style (p = 0.86), the reading/writing learning style (p = 0.20), and the kinesthetic learning style (p = 0.32). In addition, there was no significant difference between the scores on the final clinical course among the students who had different preferences for learning style. However, there was a significant difference between the mean of the final exam scores in students with and without visual learning style preference (p = 0.03), with the former having higher mean scores. There was no significant relationship between preferred learning styles and gender (p > 0.05). Conclusion The majority of dental students preferred multimodal learning styles, and there was a significant difference between the mean of the final exam scores for students with and without a preference for the visual learning style. In addition, there were no differences in the preferred learning styles between male and female students. PMID:27382442

Mechanism Research of Arch Dam Abutment Forces during Overload

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Yu Xia

2015-01-01

Full Text Available This paper presents research on the abutment forces of a double-curvature arch dam during overload based on numerical calculation results obtained through finite element method by Ansys. Results show that, with an increase in elevation, the abutment forces and bending moment of the arch dam increase first and then decrease from the bottom to the top of the dam. Abutment forces and bending moment reach their maximum at the middle or middle-down portion of the dam. The distributions of abutment forces and moment do not change during overload. The magnitude of each arch layer’s forces and moment increases linearly during overload. This result indicates that each arch layer transmits bearing loads to the rocks of the left and right banks steadily. This research explains the operating mechanism of an arch dam under normal and overload conditions. It provides a simple method to calculate the distribution of forces Fx and Fy and a new method to calculate the overload factor of an arch dam through the estimation of arch layers based on the redistribution characteristic of arch abutment forces.

[Outcomes of endovascular repairing aortic arch disease hybrid with supra-arch debranching procedures].

Science.gov (United States)

Wang, Mian; Chang, Guangqi; Yin, Henghui; Yao, Chen; Wang, Jinsong; Wang, Shenming

2015-11-01

To summarize the experience of endovascular repairing aortic arch disease hybrid with supra-arch debranching procedures. It was a retrospective study. From January 2002 to December 2014, 42 high risk patients with aortic arch disease were treated by supra-arch debranching hybrid with subsequent endovascular repair in the First Affiliated Hospital of Sun Yat-sen University. There were 39 male and 3 female patients with a mean age of (53±13) years (ranging from 34 to 80 years). Of the 42 patients, 7 were thoracic aortic aneurysm, 20 were Stanford type B aortic dissection and 15 were Stanford type A aortic dissection. After the supra-aortic debranching technique, simultaneous (n=16) or staged (n=26, mean interval (7±3) days) endovascular repair were performed. Fisher exact test was used to compare the in-hospital mortality of ascending aorta based debranching and non-ascending aorta based debranching. Technical success rate was 81.0% (34/42). The overall 30-day complication rate was 31.0% (13/42), including 3 cerebral stroke (7.1%), 8 endoleak (19.0%, including 6 type I endoleak and 2 type II endoleak), 1 circulatory failure, 1 aorto-tracheal fistula. The 30-day mortality was 9.5% (4/42), 2 died of cerebral stroke, 1 died of circulatory failure, 1 died of aorto-tracheal fistula. The in-hospital mortality of ascending aorta based debranching group was obviously higher than that of the non-ascending aorta based debranching group (4/16 vs. 0, P=0.02). The median time of follow-up was 64.8 (2 to 156.9) months. CT scanning was performed at 1, 3 months after surgery and annually thereafter. The overall survival rate was 76.6%. During the follow-up period, there was 4 deaths, and 2 of them were aortic artery related (5.3%). There were 4 de novo complications during the follow-up period, 1 stroke attributed to bypass occlusion was cured by medical treatment, 2 pseudoaneurysm was successfully treated with open surgery, 1 stent-graft induced new distal entry tear was

Implant-Supported PMMA Monolithic Full-Arch Rehabilitation with Surgical Computer-Planned Guide and Immediate Provisional: A Case Report with One Year Follow-Up

Directory of Open Access Journals (Sweden)

Vincenzo Luca Zizzari

2018-01-01

Full Text Available The aim of this case report is to describe the surgical and prosthetic procedures to achieve maxillary and mandibular implant-supported PMMA monolithic full-arch rehabilitation (PMFR with surgical computer-planned guide and immediate provisional. In such cases, the correct planning of dental implants’ position, length, and diameter and the prosthetic phases via computer-aided design are very important to achieve good aesthetic and functional long-lasting results.

Implant-Supported PMMA Monolithic Full-Arch Rehabilitation with Surgical Computer-Planned Guide and Immediate Provisional: A Case Report with One Year Follow-Up

OpenAIRE

Zizzari, Vincenzo Luca; Tacconelli, Gianmarco

2018-01-01

The aim of this case report is to describe the surgical and prosthetic procedures to achieve maxillary and mandibular implant-supported PMMA monolithic full-arch rehabilitation (PMFR) with surgical computer-planned guide and immediate provisional. In such cases, the correct planning of dental implants’ position, length, and diameter and the prosthetic phases via computer-aided design are very important to achieve good aesthetic and functional long-lasting results.

Frequency and Type of Prosthetic Complications Associated with Interim, Immediately Loaded Full-Arch Prostheses: A 2-Year Retrospective Chart Review.

Science.gov (United States)

Drago, Carl

2016-08-01

The purpose of this report was to retrospectively evaluate implant and immediate full-arch prosthesis survival rates over a 24-month period; patients were consecutively treated with immediate occlusal loading. Dental arch, gender, and implant orientation (vertical vs. tilted) were also noted. All Brånemark System implants (Nobel Active) and interim, all-acrylic resin prostheses placed in patients following an All-on-Four™ protocol, in a single private practice were assessed by retrospective patient chart review. The amount of space provided surgically for implant restorative components and prostheses was determined from measurements of the vertical heights of the interim prostheses in the right/left anterior and posterior segments. These measurements were made in the laboratory. Interim prosthetic repairs (type, frequency, length of time from insertion) were analyzed by type, arch, gender, and implant orientation. Implant survival and insertion torque values were also measured. Inclusion criteria consisted of all Brånemark System implants placed with the All-on-Four protocol from September 1, 2011, until August 31, 2013. Specific dietary instructions were given for the first 7 days immediately postoperatively and for the weeks prior to insertion of the definitive prostheses. One hundred twenty-nine patients, comprising 191 arches (766 implants) from September 1, 2011, until August 31, 2013, were included in the study. One patient experienced implant failure yielding an overall implant survival rate (SR) of 99.5% (762 of 766). Four hundred twenty-six of 430 maxillary implants and 336 of 336 mandibular implants survived for SRs of 99.1% and 100%, respectively. Regarding implant orientation, 415 of 417 tilted implants (SR 99.5%) and 343 of 345 (CSR 95.6%) vertical implants were noted to be clinically stable. Interim, all-acrylic resin prostheses were in place for a mean of 199.2 days; mandibular prostheses were in place for an average of 195.4 days; maxillary

An Investigation into the Relationship between Owner Knowledge, Diet, and Dental Disease in Guinea Pigs (Cavia porcellus

Directory of Open Access Journals (Sweden)

Rosemary Norman

2016-11-01

Full Text Available Recent studies have highlighted a high prevalence of dental disease in domestic guinea pigs, yet the aetiology of this multi-factorial disease is still unclear. Factors that have been associated with dental disease include feeding a diet that is high in energy but low in fibre, feeding an insufficiently abrasive diet, a lack of dietary calcium, and genetics. As many of these factors relate to the husbandry requirements of guinea pigs, owner awareness of dietary requirements is of the utmost importance. An online questionnaire was created based on previous research into the husbandry and feeding of rabbits. Guinea pig owners were asked to answer questions on the clinical history of their animals and their diet and management. In total, 150 surveys were completed for 344 guinea pigs, where owners of multiple animals could complete the survey for individuals. According to the owners, 6.7% of guinea pigs had been clinically diagnosed with dental disease, but 16.6% had signs consistent with dental disease. The specific clinical signs of having difficulty eating (Exp(B = 33.927, Nagelkerke R 2 = 0.301, p < 0.05 and producing fewer or smaller faecal droppings (Exp(B = 13.733, Nagelkerke R 2 = 0.149, p < 0.05 were predictive for the presence of dental disease. Having access to an outside environment, including the use of runs on both concrete and grass, was significantly related to not displaying clinical signs of dental disease (Exp(B = 1.894, Nagelkerke R 2 = 0.021, p < 0.05. There was no significant relationship between owner knowledge, guinea pig diet, and dental disease in the study population. This study highlights the importance of access to the outdoors for the health and welfare of guinea pigs in addition to the need for owners to be alert to key clinical signs. A relationship between diet and dental disease was not identified in this study; however, the underlying aetiological causes of this condition require further investigation.

Utilização da distração osteogênica mediana sagital para tratamento da atresia mandibular Mid-sagital mandibular distraction osteogenesis for treatment of lower arch crowding

Directory of Open Access Journals (Sweden)

Luiz Guilherme Martins Maia

2007-06-01

Full Text Available OBJETIVO: relatar o tratamento de uma paciente com apinhamento severo decorrente de uma atresia maxilomandibular, tratada por meio da Distração Osteogênica da Sínfise Mandibular (DOSM. RESULTADOS: neste caso, observamos bom engrenamento dentário, diminuição do corredor bucal escuro, correção do apinhamento, boa forma de arcos e boa estética facial, num período de tempo bastante satisfatório, sem trazer dano ao tecido periodontal adjacente. CONCLUSÃO: pacientes com arcos atrésicos e apinhamento dentário podem ser beneficiados com a DOSM que, quando bem indicada, surge como uma nova forma de tratamento para casos limítrofes de apinhamento dentário, nos quais as alternativas convencionais oferecem limitações, tais como o achatamento do perfil facial, o aumento do corredor bucal e a instabilidade.OBJECTIVE: To report the treatment of a patient with severe dental crowding resulting from a maxillary mandibular atresia, treated by the osteogenic extraction of the mandible symphysis (DOSM. RESULTS: In this case there was good dental engagement, a reduction of the dark oral aisle, a correction of the crowding, good dental arch form and good facial esthetics, in a very satisfactory period of time without causing damage to the adjacent periodontal tissues. CONCLUSION: Patients with atresia arches and dental crowding can be benefited by a DOSM that when well indicated, appears as a new form of treatment in cases of maximum borderline dental crowding, in which the conventional alternatives have limitations such as flattening of the facial profile, increase in the oral aisle and instability.

Glossary to ARCH (GARCH)

DEFF Research Database (Denmark)

Bollerslev, Tim

The literature on modeling and forecasting time-varying volatility is ripe with acronyms and abbreviations used to describe the many different parametric models that have been put forth since the original linear ARCH model introduced in the seminal Nobel Prize winning paper by Engle (1982......).  The present paper provides an easy-to-use encyclopedic reference guide to this long list of ARCH acronyms.  In addition to the acronyms associated with specific parametric models, I have also included descriptions of various abbreviations associated with more general statistical procedures and ideas...

[Treatment of adult bimaxillary arch protrusion with micro-implant anchorage].

Science.gov (United States)

Chen, Cheng; Zhang, Xiao-Rong

2015-02-01

In this study, micro-implants were used in 15 adult patients with mild and moderate bimaxillary arch protrusion or crowding. Cephalometric analysis was used to analyze hard and soft-tissues change before and after treatment, with the aim to investigate the effects of treatment on adult bimaxillary arch protrusion with micro-implant anchorage. Fifteen adult patients with mild and moderate bimaxillary arch protrusion were selected in this study. Micro-implants were inserted into the zygomaticoalveolar ridge of maxilla and the external oblique line of mandible. A NiTi coil spring was attached to the micro-implant to drag the whole upper and lower dentition for distal movement. Cephalometrics were taken before and after treatment, and the changes of soft and hard-tissue profile were studied. SPSS13.0 software package was used to analyze the data. (1)Sixty micro-implants remained stable.(2)SNA, SNB had no significant changes (P>0.05), and the relationship between the maxilla and the mandible did not change significantly. U1/NA, U1-NA, L1/NB, L1-NB and U1/L1 changes in hard tissue had significant difference in cephalometric measurement (PMicro-implant can provide not only excellent skeletal anchorage but also a novel way to distalize the whole dentition efficiently.

Dentoalveolar mandibular changes with self-ligating versus conventional bracket systems: A CBCT and dental cast study

Science.gov (United States)

de Almeida, Marcio Rodrigues; Futagami, Cristina; Conti, Ana Cláudia de Castro Ferreira; Oltramari-Navarro, Paula Vanessa Pedron; Navarro, Ricardo de Lima

2015-01-01

OBJECTIVE: The aim of the present study was to compare dentoalveolar changes in mandibular arch, regarding transversal measures and buccal bone thickness, in patients undergoing the initial phase of orthodontic treatment with self-ligating or conventional bracket systems. METHODS: A sample of 25 patients requiring orthodontic treatment was assessed based on the bracket type. Group 1 comprised 13 patients bonded with 0.022-in self-ligating brackets (SLB). Group 2 included 12 patients bonded with 0.022-in conventional brackets (CLB). Cone-beam computed tomography (CBCT) scans and a 3D program (Dolphin) assessed changes in transversal width of buccal bone (TWBB) and buccal bone thickness (BBT) before (T1) and 7 months after treatment onset (T2). Measurements on dental casts were performed using a digital caliper. Differences between and within groups were analyzed by Student's t-test; Pearson correlation coefficient was also calculated. RESULTS: Significant mandibular expansion was observed for both groups; however, no significant differences were found between groups. There was significant decrease in mandibular buccal bone thickness and transversal width of buccal bone in both groups. There was no significant correlation between buccal bone thickness and dental arch expansion. CONCLUSIONS: There were no significant differences between self-ligating brackets and conventional brackets systems regarding mandibular arch expansion and changes in buccal bone thickness or transversal width of buccal bone. PMID:26154456

Young adult patient with two palatally maxillary impacted canines and forced traction on rigid arches of stabilization. Case report.

Science.gov (United States)

Mucedero, M; Pezzuto, C; Rozzi, M; Ricchiuti, M R; Cozza, P

2016-01-01

Young adult patient treated for impaction of two maxillary canines. C.S., 15 years, female. Diagnostic evaluation by clinical and radiographic examinations shows permanent dentition with persistence of 5.3 and 6.3, impaction of 1.3 and 2.3, dento-skeletal Cl I malocclusion, normodivergence of bone bases. Analysis of TC dentalscan confirms the palatal impaction of 1.3 and 2.3. The treatment plan provided an orthodontic-surgical approach for adequate space management in dental arch, evaluation of eruption movements, choice of anchorage device, surgical exposure and application of the brackets. Deciduous canines have been extracted and an edgewise appliance with rigid rectangular full thickness archwires has been used to align the arches and to obtain maximum anchorage during the forced traction. The surgical phase, for exposure of 1.3 and 2.3 respectively, performed an open technique by excisional uncovering and a close technique by a repositioned flap. The case has been finalized for the achievement of the right occlusal keys. The possibility to choose the surgical technique depending on the intraosseous position of impacted teeth in association to the edgewise therapy with full thickness arches allows to realize an effectiveness surgical-orthodontic approach for the forced traction of impacted teeth in a favourable position.

Occlusion and Temporomandibular Function among Subjects with Mandibular Distal Extension Removable Partial Dentures

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N. H. J. Creugers

2010-01-01

Full Text Available Objective. To quantify effects on occlusion and temporomandibular function of mandibular distal extension removable partial dentures in shortened dental arches. Methods. Subjects wearing mandibular extension removable partial dentures (n=25 were compared with subjects with shortened dental arches without extension (n=74 and with subjects who had worn a mandibular extension removable partial denture in the past (n=19. Subjects with complete dentitions (n=72 were controls. Data were collected at baseline and at 3-, 6-, and 9-year observations. Results. Occlusal activity in terms of reported awareness of bruxism and occlusal tooth wear of lower anterior teeth did not differ significantly between the groups. In contrast, occlusal tooth wear of premolars in shortened dental arches with or without extension dentures was significantly higher than in the controls. Differences amongst groups with respect to signs and symptoms related to temporomandibular disorders were not found. Occlusal support of the dentures did not influence anterior spatial relationship. Occlusal contacts of the denture teeth decreased from 70% for second premolars via 50% for first molars, to 30% for second molars. Conclusions. Mandibular distal extension removable partial dentures in moderate shortened dental arches had no effects on occlusion and temporomandibular function.

The value of the Gothic arch tracing in the positioning of denture teeth.

Science.gov (United States)

el-Gheriani, A S; Winstanley, R B

1988-07-01

Twenty-five subjects of three nationalities carried out Gothic arch tracings. Measurements between the side arms were compared with the upper intercuspid distances measured in the same subjects. A relationship was found which may be of value in the setting up of anterior maxillary denture teeth.

Early functional outcome of two surgical protocols used in the repair ...

African Journals Online (AJOL)

treatment protocols for primary management of patients with complete unilateral cleft ... Pediatric Surgery Unit, Zagazig University, Faculty of Medicine, Zagazig, Egypt. Tel: +0553655220 ..... Dental arch relationships. Cleft Palate. Craniofac J ...

Progressive changes in arch width from primary to early mixed dentition period: a longitudinal study.

Science.gov (United States)

Sangwan, S; Chawla, H S; Goyal, A; Gauba, K; Mohanty, U

2011-01-01

The present study was conducted to evaluate, on a longitudinal basis, the changes in intercanine and intermolar widths form the primary to the early mixed dentition periods. A total of 38 children aged 4-5 years, with normal occlusion without any proximal caries or any dental anomalies, were selected. The impressions were recorded and casts were prepared. Intercanine and intermolar widths were measured on these dental casts with the help of a digital vernier calliper. After 3 years follow-up, the impressions were recorded again and dental casts were prepared. Intercanine and intermolar widths were measured again at this stage and were compared with the baseline data using the paired t-test and the chi square test. There is a significant increase in the intercanine (3.93 + 1.70 mm) and intermolar width (1.49 + 1.77 mm) during the transition period from primary to early mixed dentition in both the arches and both the sexes. The gender-wise comparison showed a greater increase in males than in females, but this was not statistically significant. A thorough knowledge of growth changes during various stages of the mixed dentition period are important for a pediatric dentist to make an accurate diagnosis and treatment planning during preventive and interceptive orthodontics.

Prevalence of dental anomalies in deciduous dentition and its association with succedaneous dentition: A cross-sectional study of 4180 South Indian children.

Science.gov (United States)

Shilpa, G; Gokhale, Niraj; Mallineni, Sreekanth Kumar; Nuvvula, Sivakumar

2017-01-01

The objective of this study was to estimate the prevalence of dental anomalies in primary dentition of Indian population. This cross-sectional study was conducted on 4180 children in the age of 2-6 years. Anomalies were classified based on Kreiborg criteria. The term "double tooth" was used to avoid misinterpretation between gemination. and fusion. Patients having radiographs were also examined for associated dental anomalies in permanent dentition. The occurrence and gender prevalence were evaluated using descriptive statistics. About 95. (2.27%) children exhibited at least one dental anomaly. Thirty.seven children showed 51 missing teeth. (0.88%), mostly in lower right incisors with a statistically significant difference between arches. (P = 0.0056) Nine children. (0.21%) had supernumerary teeth commonly in the right maxilla. Two cases of oligodontia. (0.04%) and talon cusps. (0.04%) and one case of triple tooth. (0.02%) were observed. Forty children. (0.95%) had 43 double teeth mostly in the right mandible with a statistically significant difference between the arches. (P = 0.0105). No significant difference was observed based on gender and arch, but they were statistically significant between the right and left sides. (P = 0.018). Among the children with radiographs available, 45% showed anomalies in the succedaneous dentition. The prevalence rates of children with double tooth, hypodontia, and hyperdontia in our study are 0.95%, 0.88%, and 0.21%, respectively. The overall prevalence rate of anomalies among boys was higher than girls.

Fragile X syndrome: panoramic radiographic evaluation of dental anomalies, dental mineralization stage, and mandibular angle

Science.gov (United States)

Sabbagh-Haddad, Aida; Haddad, Denise Sabbagh; Michel-Crosato, Edgard; Arita, Emiko Saito

2016-01-01

ABSTRACT Fragile X syndrome (FXS) is a disorder linked to the chromosome X long arm (Xq27.3), which is identified by a constriction named fragile site. It determines various changes, such as behavioral or emotional problems, learning difficulties, and intellectual disabilities. Craniofacial abnormalities such as elongated and narrow face, prominent forehead, broad nose, large and prominent ear pavilions, strabismus, and myopia are frequent characteristics. Regarding the oral aspects, deep and high-arched palate, mandibular prognathism, and malocclusion are also observed. Objective: The purpose of this study was to evaluate the dental radiographic characteristics as described in 40 records of patients with panoramic radiography. Material and Methods: The patients were in the range of 6–17 years old, and were divided into two groups (20 subjects who were compatible with the normality standard and 20 individuals diagnosed with the FXS), which were matched for gender and age. Analysis of the panoramic radiographic examination involved the evaluation of dental mineralization stage, mandibular angle size, and presence of dental anomalies in both deciduous and permanent dentitions. Results: The results of radiographic evaluation demonstrated that the chronology of tooth eruption of all third and second lower molars is anticipated in individuals with FXS (pdental anomalies. In addition, an increase was observed in the mandibular angle size in the FXS group (pdental radiographic changes is of great importance for dental surgeons to plan the treatment of these individuals. PMID:27812623

The relationship between parenting, family interaction and childhood dental caries: a case-control study

NARCIS (Netherlands)

de Jong-Lenters, M.; Duijster, D.; Bruist, M.A.; Thijssen, J.; de Ruiter, C.

2014-01-01

The aim of this case-control study was to explore the relationship between parenting practices, parent-child interaction and childhood dental caries, using a sample of 5-8-year old children from the Netherlands. Cases were defined as children with four or more decayed, missing or filled teeth and

The relationship between parenting, family interaction and childhood dental caries: A case-control study

NARCIS (Netherlands)

Jong-Lenters, M. de; Duijster, D.; Bruist, M.A.; Thijssen, J.; Ruiter, C. de

2014-01-01

The aim of this case-control study was to explore the relationship between parenting practices, parent-child interaction and childhood dental caries, using a sample of 5-8-year old children from the Netherlands. Cases were defined as children with four or more decayed, missing or filled teeth and

Comparison of Arch Width Changes Following Orthodontic ...

African Journals Online (AJOL)

2015-11-21

Nov 21, 2015 ... Materials and Methods: The study was conducted with pre- and post-treatment digital models from ... or posterior arch width following orthodontic treatment ..... premolar extraction cases show significant arch width increases in ...

Class II young adult treatment with Twin Force Bite corrector: 10-year follow-up

Directory of Open Access Journals (Sweden)

Ozge Uslu-Akcam

2017-01-01

Full Text Available One of the most preferred compliance free fixed functional appliances in nongrowing patients is Twin Force Bite corrector (TFBC. The aim of this case report is to evaluate the effectiveness of TFBC in the treatment of an adult Class II case. A 16-year 1-month-old boy having skeletal and dental Class II relationship was selected. Roth 0.018 × 0.025 inch slots brackets were attached; a fixed lingual arch in the mandibular dental arch and a Nance appliance in the maxillary dental arch were used to increase anchorage. The TFBC therapy used for sagittal activation and stimulation of forward mandibular growth lasted for 3 months. The post-TFBC treatment lasted 6 months and the total treatment time was 9 months. Treatment of a young adult Class II malocclusion with TFBC resulted in a Class I molar occlusion, an ideal overjet, overbite, and incisor angulation in a short time and maintained in the 10-year follow-up.

Automatic teeth axes calculation for well-aligned teeth using cost profile analysis along teeth center arch.

Science.gov (United States)

Kim, Gyehyun; Lee, Jeongjin; Seo, Jinwook; Lee, Wooshik; Shin, Yeong-Gil; Kim, Bohyoung

2012-04-01

In dental implantology and virtual dental surgery planning using computed tomography (CT) images, the examination of the axes of neighboring and/or biting teeth is important to improve the performance of the masticatory system as well as the aesthetic beauty. However, due to its high connectivity to neighboring teeth and jawbones, a tooth and/or its axis is very elusive to automatically identify in dental CT images. This paper presents a novel method of automatically calculating individual teeth axes. The planes separating the individual teeth are automatically calculated using cost profile analysis along the teeth center arch. In this calculation, a novel plane cost function, which considers the intensity and the gradient, is proposed to favor the teeth separation planes crossing the teeth interstice and suppress the possible inappropriately detected separation planes crossing the soft pulp. The soft pulp and dentine of each individually separated tooth are then segmented by a fast marching method with two newly proposed speed functions considering their own specific anatomical characteristics. The axis of each tooth is finally calculated using principal component analysis on the segmented soft pulp and dentine. In experimental results using 20 clinical datasets, the average angle and minimum distance differences between the teeth axes manually specified by two dentists and automatically calculated by the proposed method were 1.94° ± 0.61° and 1.13 ± 0.56 mm, respectively. The proposed method identified the individual teeth axes accurately, demonstrating that it can give dentists substantial assistance during dental surgery such as dental implant placement and orthognathic surgery.

Integration of Digital Dental Casts in Cone-Beam Computed Tomography Scans

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Rangel, Frits A.; Maal, Thomas J. J.; Bergé, Stefaan J.; Kuijpers-Jagtman, Anne Marie

2012-01-01

Cone-beam computed tomography (CBCT) is widely used in maxillofacial surgery. The CBCT image of the dental arches, however, is of insufficient quality to use in digital planning of orthognathic surgery. Several authors have described methods to integrate digital dental casts into CBCT scans, but all reported methods have drawbacks. The aim of this feasibility study is to present a new simplified method to integrate digital dental casts into CBCT scans. In a patient scheduled for orthognathic surgery, titanium markers were glued to the gingiva. Next, a CBCT scan and dental impressions were made. During the impression-taking procedure, the titanium markers were transferred to the impression. The impressions were scanned, and all CBCT datasets were exported in DICOM format. The two datasets were matched, and the dentition derived from the scanned impressions was transferred to the CBCT of the patient. After matching the two datasets, the average distance between the corresponding markers was 0.1 mm. This novel method allows for the integration of digital dental casts into CBCT scans, overcoming problems such as unwanted extra radiation exposure, distortion of soft tissues due to the use of bite jigs, and time-consuming digital data handling. PMID:23050159

Clarifying the anatomy of the fifth arch artery

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Saurabh Kumar Gupta

2016-01-01

Full Text Available The artery allegedly forming in the fifth pharyngeal arch has increasingly been implicated as responsible for various vascular malformations in patients with congenitally malformed hearts. Observations from studies on developing embryos, however, have failed to provide support to substantiate several of these inferences such that the very existence of the fifth arch artery remains debatable. To the best of our knowledge, in only a solitary human embryo has a vascular channel been found that truly resembled the artery of the fifth arch. Despite the meager evidence to support its existence, the fifth arch artery has been invoked to explain the morphogenesis of double-barreled aorta, some unusual forms of aortopulmonary communications, and abnormalities of the brachiocephalic arteries. In most of these instances, the interpretations have proved fallible when examined in the light of existing knowledge of cardiac development. In our opinion, there are more plausible alternative explanations for the majority of these descriptions. Double-barreled aorta is more likely to result from retention of the recently identified dorsal collateral channels while abnormalities of brachiocephalic arteries are better explained on the basis of extensive remodeling of aortic arches during fetal development. Some examples of aortopulmonary communications, nonetheless, may well represent persistence of the developing artery of the fifth pharyngeal arch. We here present one such case - a patient with tetralogy of Fallot and pulmonary atresia, in whom the fifth arch artery provided a necessary communication between the ascending aorta and the pulmonary arteries. In this light, we discuss the features we consider to be essential before attaching the tag of "fifth arch artery" to a candidate vascular channel.

The Evaluation of Relationship between Self-efficacy in Research and Research Performance of Dental Student, of Yazd Dental College in 2014

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AR Davari

2015-09-01

Full Text Available Introduction: Achieve to maximum progress and improvement, just depends on addressing targeted research investment and investment of researchers and students. So, the present study was accomplished by the aim of evaluation of the relationship between self-efficacy in research and research performance of dental student of Yazd Dental College in 2014.   Methods: In this cross-sectional study, all interns and assistants in Yazd Dental School were participated. The required data were collected by using the Self-efficacy in Research and Research Performance questionnaire plus demographic variables (age, sex and duration of using denture. The data were analyzed by SPSS ver.16 using ANOVA, T-test and Pearson's correlation coefficient.   Results: In the present study, 80 students with the mean age 27.30±4.67 years were participated. Twenty-two students (27.5% were males and 58 (72.5% were females. The overall mean of self-efficacy in research was 159.79 ± 27.69. And the mean of research performance was 11.02 ± 16.37. The results showed that there was a significant and positive relationship between the overall scale of self-efficacy and research (p-value=0.004,r= .03. Based on the age, there was no significant difference in the mean score of self-efficacy in research in all aspects but in the areas of skills and expertise   (p>0.05. There was a significant difference in the mean score of research performance in terms of the age(p-value=0.023. There was no statistical significant between the overall mean score and the score of seven parts of self-efficacy in research and research performance in the terms of sex (P>0.05.   Conclusions: Regarding the association of self-efficacy in research with research performance of dental students, it can be stated that awareness of the level of self efficacy in research can lead to better planning for improving the research performance.

Nonstationary ARCH and GARCH with t-distributed Innovations

DEFF Research Database (Denmark)

Pedersen, Rasmus Søndergaard; Rahbek, Anders

Consistency and asymptotic normality are established for the maximum likelihood estimators in the nonstationary ARCH and GARCH models with general t-distributed innovations. The results hold for joint estimation of (G)ARCH effects and the degrees of freedom parameter parametrizing the t-distribut......Consistency and asymptotic normality are established for the maximum likelihood estimators in the nonstationary ARCH and GARCH models with general t-distributed innovations. The results hold for joint estimation of (G)ARCH effects and the degrees of freedom parameter parametrizing the t......-distribution. With T denoting sample size, classic square-root T-convergence is shown to hold with closed form expressions for the multivariate covariances....

[Analysis of the interaction of genotypic and paratypic factors in the development of maxillo-dental anomalies in ontogeny].

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Lil'in, E T; Persin, L S; Titov, V I; Danilina, O A

1996-09-01

Component analysis of total phenotypic variance was used to analyze data on 80 pairs of twins aged 3 to 18 years, examined in the Stupino outpatient dental clinic, Moscow oblast. Genotypic and environmental factors are shown to play different roles in the development of abnormalities of teeth, dental arches, and occlusion at different ontogenetic periods of deciduous, mixed, and permanent dentition. Periods when paratypic factors prevailed were revealed. This made it possible to identity periods when prophylaxis and orthodontic treatment are the most advisable.

Relationship between procrastination and academic performance among a group of undergraduate dental students in India.

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Lakshminarayan, Nagesh; Potdar, Shrudha; Reddy, Siddana Goud

2013-04-01

Procrastination, generally defined as a voluntary, irrational delay of behavior, is a prevalent phenomenon among college students throughout the world and occurs at alarmingly high rates. For this study, a survey was conducted of 209 second-, third-, and fourth-year undergraduate dental students of Bapuji Dental College and Hospital, Davangere, India, to identify the relationship between their level of procrastination and academic performance. A sixteen-item questionnaire was used to assess the level of procrastination among these students. Data related to their academic performance were also collected. Spearman's correlation coefficient test was used to assess the relationship between procrastination and academic performance. It showed a negative correlation of -0.63 with a significance level of pprocrastination scores performed below average in their academics. In addition, analysis with the Mann-Whitney U test found a significant difference in procrastination scores between the two gender groups (pprocrastination and vice versa.

Determination of metal ions released by stainless steel arch bar into bio-fluids

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Lori A. Joseph

2009-04-01

Full Text Available The amounts of cobalt, iron, manganese, nickel and chromium ions released from new and reused stainless steel arch bar used for maxillomandibular fixation was determined in Hank’s solutions of different hydrogen and chloride ions concentrations, whole blood serum and phosphate buffered saline (PBS in vitro, over a six-week immersion time at 37 oC, by atomic absorption spectrophotometry. The corrosion levels of the wires due to effects of media and incubation times in the bio-fluids were compared by Duncan’s two-way ANOVA (P less than 0.05. Pearson’s correlation was used in establishing relationship in the amounts of metal ions released by new and reused arch bars. The study indicated that the reused wires released more ions than new ones at all time points. The variation of pH and chloride ions of the bio-fluids had a significant effect on the amount of Ni, Mn and Cr ions released. Ageing prior use of arch bars significantly increased Ni ions released into the bio-fluids.

Evaluation of accuracy of complete-arch multiple-unit abutment-level dental implant impressions using different impression and splinting materials.

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Buzayan, Muaiyed; Baig, Mirza Rustum; Yunus, Norsiah

2013-01-01

This in vitro study evaluated the accuracy of multiple-unit dental implant casts obtained from splinted or nonsplinted direct impression techniques using various splinting materials by comparing the casts to the reference models. The effect of two different impression materials on the accuracy of the implant casts was also evaluated for abutment-level impressions. A reference model with six internal-connection implant replicas placed in the completely edentulous mandibular arch and connected to multi-base abutments was fabricated from heat-curing acrylic resin. Forty impressions of the reference model were made, 20 each with polyether (PE) and polyvinylsiloxane (PVS) impression materials using the open tray technique. The PE and PVS groups were further subdivided into four subgroups of five each on the bases of splinting type: no splinting, bite registration PE, bite registration addition silicone, or autopolymerizing acrylic resin. The positional accuracy of the implant replica heads was measured on the poured casts using a coordinate measuring machine to assess linear differences in interimplant distances in all three axes. The collected data (linear and three-dimensional [3D] displacement values) were compared with the measurements calculated on the reference resin model and analyzed with nonparametric tests (Kruskal-Wallis and Mann-Whitney). No significant differences were found between the various splinting groups for both PE and PVS impression materials in terms of linear and 3D distortions. However, small but significant differences were found between the two impression materials (PVS, 91 μm; PE, 103 μm) in terms of 3D discrepancies, irrespective of the splinting technique employed. Casts obtained from both impression materials exhibited differences from the reference model. The impression material influenced impression inaccuracy more than the splinting material for multiple-unit abutment-level impressions.

Characterizing saccular aortic arch aneurysms from the geometry-flow dynamics relationship.

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Natsume, Kayoko; Shiiya, Norihiko; Takehara, Yasuo; Sugiyama, Masataka; Satoh, Hiroshi; Yamashita, Katsushi; Washiyama, Naoki

2017-06-01

Low wall shear stress (WSS) has been reported to be associated with accelerated atherosclerosis, aneurysm growth, or rupture. We evaluated the geometry of aortic arch aneurysms and their relationship with WSS by using the 4-dimensional flow magnetic resonance imaging to better characterize the saccular aneurysms. We analyzed the geometry in 100 patients using multiplanar reconstruction of computed tomography. We evaluated WSS and vortex flow using 4-dimensional flow magnetic resonance imaging in 16 of them, which were compared with 8 age-matched control subjects and eight healthy young volunteers. Eighty-two patients had a saccular aneurysm, and 18 had a fusiform aneurysm. External diameter/aneurysm length ratio and sac depth/neck width ratio of the fusiform aneurysms were constant at 0.76 ± 0.18 and 0.23 ± 0.09, whereas those of saccular aneurysms, especially those involving the outer curvature, were higher and more variable. Vortex flow was always present in the aneurysms, resulting in low WSS. When the sac depth/neck width ratio was less than 0.8, peak WSS correlated inversely with luminal diameter even in the saccular aneurysms. When this ratio exceeded 0.8, which was the case only with the saccular aneurysms, such correlation no longer existed and WSS was invariably low. Fusiform aneurysms elongate as they dilate, and WSS is lower as the diameter is larger. Saccular aneurysms dilate without proportionate elongation, and they, especially those occupying the inner curvature, have higher and variable sac depth/neck width ratio. When this ratio exceeds 0.8, WSS is low regardless of diameter, which may explain their malignant clinical behavior. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Relationship between the psychosocial impact of dental aesthetics and perfectionism and self-esteem.

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Venete, Alina; Trillo-Lumbreras, Eva; Prado-Gascó, Vicente-Javier; Bellot-Arcís, Carlos; Almerich-Silla, José-Manuel; Montiel-Company, José-María

2017-12-01

Awareness of the influence of personality traits such as self-esteem and perfectionism on the aesthetic self-image can help clinicians to improve their patients' satisfaction and quality of life. The main objective of this study was to examine the relationship between self-esteem, perfectionism and the psychosocial impact of dental aesthetics, and their association with gender. A descriptive-analytical cross-sectional study was conducted in a sample of 301 students of the Faculty of Medicine and Dentistry of the University of Valencia, aged between 18 and 30 years. Each participant was asked to complete a survey comprising three questionnaires: PIDAQ (Psychosocial Impact of Dental Aesthetics Questionnaire), MPS (Multidimensional Perfectionism Scale) and RSS (Rosenberg Self-esteem Scale). The response rate was 79%. The mean age was 20.8 years; 226 were women (75 %) and 75 were men (25 %). A negative correlation (Pearson = -0.387) was found between the total PIDAQ score and self-esteem. The correlation with perfectionism was found to be positive (Pearson = 0.281). On comparing the questionnaire and subscale scores by gender, the only statistically significant differences were in perfectionism (men 97.4, women 89.1) and self-confidence (men 22.1, women 23.5). The students most affected by poor dental aesthetics had lower self-esteem and higher levels of perfectionism. The men presented higher levels of perfectionism than the women, while the latter displayed greater self-confidence in their dental aesthetics. Clinicians should pay greater attention to these traits and to their implications for treating these patients. Key words: Psychosocial impact of dental aesthetics questionnaire, multidimensional perfectionism scale, rosenberg self-esteem scale, students.

Arch translocation and the intra-arch elephant-trunk technique with collared graft for extended chronic dissecting aortic aneurysm

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Ikenaga Shigeru

2013-01-01

Full Text Available Abstract Management of extensive, chronic, dissecting aortic aneurysms after prior repair of the ascending aorta presents a technical challenge for surgeons. A symptomatic 64-year-old patient was admitted for elective surgical repair of an aortic annular dilatation, causing severe aortic regurgitation, and a Crawford type II extended thoracoabdominal aneurysm, 4 years after he underwent primary repair of an acute aortic dissection. The aorta was diffusely dilated, and there were no sites beyond the distal aortic arch where anastomosis could be performed. We successfully performed total aortic replacement with a 2-stage strategy, using an arch translocation technique and an intra-arch elephant-trunk technique.

Occlusal considerations for dental implant restorations.

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Bergmann, Ranier H

2014-01-01

When placed, dental implants are put into an ever-changing oral environment in which teeth can continue to migrate. Yet, the implants themselves are ankylosed. This can lead to occlusal instability. Teeth may continue to erupt, leaving the implants in infraocclusion. Teeth may move mesially away from an implant, requiring modification to close an open contact point. Friction in the connection between teeth and implants can lead to intrusion of teeth and damage to the periodontal attachment apparatus. Implant occlusion with shallow incisal guidance minimizes lateral and tipping forces. Cross-arch stabilization allows the best distribution of occlusal forces. The choice of restorative materials influences long-term occlusal stability.

Is there a prospect for hybrid aortic arch surgery?

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Bashir, Mohamad; Harky, Amer; Bilal, Haris

2018-05-16

The surge of endovascular repair of aortic aneurysm in current modern aortic surgery practice has been the key for surgical management of elective cases of thoracic aortic aneurysms. This has paved way for the combined hybrid approach to be amongst the armamentarium for the management of aortic arch disease. The pivotal understanding of the aortic arch natural history coupled with device technology advancement allowed surgeons insight into delivery of hybrid surgery with acceptable morbidity and mortality results. This review article provides current insights into hybrid technique of aortic arch aneurysm repair and the evidences behind its applicability to arch surgery. It is aimed to highlight the challenges encountered for this innovative approach and correlate its challenges to those that are met by the conventional open aortic arch repair.

Effect of Obesity on Arch Index in Young Adults

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Sneha Sameer Ganu

2013-01-01

Full Text Available Background: Excessive increases in weight bearing forces caused by obesity may negatively affect the lower limbs and feet but minimal research has examined the long-term loading effects of obesity on the musculoskeletal system, particularly in reference to the feet. Objectives: The purpose of the study was to investigate the effect of obesity on medial longitudinal arch of foot in young adults. Method: 60 subjects, 30 obese & 30 non obese were assessed for height & weight using standard technique. Radiographic images under static condition were used for calculating the arch index. Result: The arch index of obese subjects was significantly lower than the non obese subjects & there is a negative correlation between the BMI & the arch index. Conclusion: These results suggests that obesity lowers the medial longitudinal arch of foot.

Spectrum of Dental Phenotypes in Nonsyndromic Orofacial Clefting.

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Howe, B J; Cooper, M E; Vieira, A R; Weinberg, S M; Resick, J M; Nidey, N L; Wehby, G L; Marazita, M L; Moreno Uribe, L M

2015-07-01

Children with oral clefts show a wide range of dental anomalies, adding complexity to understanding the phenotypic spectrum of orofacial clefting. The evidence is mixed, however, on whether the prevalence of dental anomalies is elevated in unaffected relatives and is mostly based on small samples. In the largest international cohort to date of children with nonsyndromic clefts, their relatives, and controls, this study characterizes the spectrum of cleft-related dental anomalies and evaluates whether families with clefting have a significantly higher risk for such anomalies compared with the general population. A total of 3,811 individuals were included: 660 cases with clefts, 1,922 unaffected relatives, and 1,229 controls. Dental anomalies were identified from in-person dental exams or intraoral photographs, and case-control differences were tested using χ(2) statistics. Cases had higher rates of dental anomalies in the maxillary arch than did controls for primary (21% vs. 4%, P = 3 × 10(-8)) and permanent dentitions (51% vs. 8%, P = 4 × 10(-62)) but not in the mandible. Dental anomalies were more prevalent in cleft lip with cleft palate than other cleft types. More anomalies were seen in the ipsilateral side of the cleft. Agenesis and tooth displacements were the most common dental anomalies found in case probands for primary and permanent dentitions. Compared with controls, unaffected siblings (10% vs. 2%, P = 0.003) and parents (13% vs. 7%, P = 0.001) showed a trend for increased anomalies of the maxillary permanent dentition. Yet, these differences were nonsignificant after multiple-testing correction, suggesting genetic heterogeneity in some families carrying susceptibility to both overt clefts and dental anomalies. Collectively, the findings suggest that most affected families do not have higher genetic risk for dental anomalies than the general population and that the higher prevalence of anomalies in cases is primarily a physical consequence of the

Evaluation of Maxillary Interpremolar, Molar Width by DRNA Indices and Arch Dimension, Arch Form in Maratha Population

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Nitin Dungarwal

2013-01-01

Conclusion: Significant correlation was found between the sum of maxillary incisors and interpremolar width but not with the intermolar width while sum of mandibular incisors showed significant correlation with the interpremolar and intermolar arch width. There is no single arch form unique to any of the ethnic groups. A new formula is proposed to determine the premolar and molar index.

Track-Bridge Longitudinal Interaction of Continuous Welded Rails on Arch Bridge

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Rong Chen

2013-01-01

Full Text Available Taking arch bridges, including deck, half-through, and through arch bridges (short for DAB, HTAB, and TAB as examples, mechanics analysis models of longitudinal interaction between continuously welded rails (short for CWRs and arch bridges are established. Based on the finite element method (FEM, the longitudinal interaction calculation software of CWR on arch bridges has been developed. Focusing on an HTAB, the tension, compression, and deflection conditions are calculated and analyzed. The results show that the mechanics analysis models of three types of arch bridges can truly reflect the real state of the structure; the calculation software can be used for systematic research of the CWR on arch bridge; as for HTAB, temperature difference of arch rib has a small effect on rail tension/compression, and arch bridge can be simplified as a continuous beam for rail tension/compression additional force calculation; in calculation of deflection conditions of HTAB, it is suggested that train loads are arranged on half span and full span and take the direction of load entering bridge into account. Additionally, the deflection additional force variation of CFST basket handle arch bridge is different from that of ordinary bridge.

Bovine aortic arch: A novel association with thoracic aortic dilation

International Nuclear Information System (INIS)

Malone, C.D.; Urbania, T.H.; Crook, S.E.S.; Hope, M.D.

2012-01-01

Aim: To investigate whether there is a link between bovine arch and thoracic aortic aneurysm. Materials and methods: Computed tomography (CT) and magnetic resonance imaging (MRI) images of the thorax of 191 patients with dilated thoracic aortas and 391 consecutive, unselected patients as controls were retrospectively reviewed. Bovine arch was considered present if either a shared origin of the left common carotid and innominate arteries or an origin of the left common carotid from the innominate artery was identified. A chi-square test was used to evaluate the significance of differences between subgroups. Results: A trend towards increased prevalence of bovine arch was seen in patients with dilated aortas (26.2%) compared to controls (20.5%, p = 0.12). The association was statistically significant in patients over 70 years old (31.9%, p = 0.019) and when dilation involved the aortic arch (47.6%, p = 0.003). Conclusions: An association between bovine arch and aortic dilation is seen in older patients, and when dilation involves the aortic arch. Bovine arch should be considered a potential risk factor for thoracic aortic aneurysm.

Coexistence of bilateral first and second branchial arch anomalies

Science.gov (United States)

Thakur, J S; Shekar, Vidya; Saluja, Manika; Mohindroo, N K

2013-01-01

Branchial arch anomalies are one of the most common congenital anomalies that are usually unilateral and bilateral presentation is rare. The simultaneous presence of bilateral second branchial arch anomalies along with bilateral first arch anomalies is extremely rare, with only three such cases reported in the literature. We present two non-syndromic cases of coexisting bilateral first and second arch anomalies. Developmental anomalies of the branchial apparatus account for 17% of all paediatric cervical masses and are the most common type of congenital cervical mass. They usually present in the paediatric age group. About 96–97% of these anomalies are unilateral. Bilateral presentation is seen in 2–3% having a strong familial association. Congenital syndromes also have been associated with first and second branchial arch anomalies. Thorough clinical examination and investigations should be done to rule out these syndromes. PMID:23580675

Arch-Axis Coefficient Optimization of Long-Span Deck-Type Concrete-Filled Steel Tubular Arch Bridge

Science.gov (United States)

Liu, Q. J.; Wan, S.; Liu, H. C.

2017-11-01

This paper is based on Nanpuxi super major bridge which is under construction and starts from Wencheng Zhejiang province to Taishun highway. A finite element model of the whole bridge is constructed using Midas Civil finite element software. The most adverse load combination in the specification is taken into consideration to determine the method of calculating the arch-axis coefficient of long-span deck-type concrete-filled steel tubular arch bridge. By doing this, this paper aims at providing references for similar engineering projects.

Progressive changes in arch width from primary to early mixed dentition period: A longitudinal study

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S Sangwan

2011-01-01

Full Text Available Objective: The present study was conducted to evaluate, on a longitudinal basis, the changes in intercanine and intermolar widths form the primary to the early mixed dentition periods. Materials and Methods: A total of 38 children aged 4-5 years, with normal occlusion without any proximal caries or any dental anomalies, were selected. The impressions were recorded and casts were prepared. Intercanine and intermolar widths were measured on these dental casts with the help of a digital vernier calliper. After 3 years follow-up, the impressions were recorded again and dental casts were prepared. Intercanine and intermolar widths were measured again at this stage and were compared with the baseline data using the paired t-test and the chi square test. Results: There is a significant increase in the intercanine (3.93 + 1.70 mm and intermolar width (1.49 + 1.77 mm during the transition period from primary to early mixed dentition in both the arches and both the sexes. The gender-wise comparison showed a greater increase in males than in females, but this was not statistically significant. Conclusion: A thorough knowledge of growth changes during various stages of the mixed dentition period are important for a pediatric dentist to make an accurate diagnosis and treatment planning during preventive and interceptive orthodontics.

Double aortic arch

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Surgery can be done to fix double aortic arch. The surgeon ties off the smaller branch and separates it from the larger branch. Then the surgeon closes the ends of the aorta with stitches. This relieves pressure on the esophagus and windpipe.

Monitoring system of arch bridge for safety network management

Science.gov (United States)

Joo, Bong Chul; Yoo, Young Jun; Lee, Chin Hyung; Park, Ki Tae; Hwang, Yoon Koog

2010-03-01

Korea has constructed the safety management network monitoring test systems for the civil infrastructure since 2006 which includes airport structure, irrigation structure, railroad structure, road structure, and underground structure. Bridges among the road structure include the various superstructure types which are Steel box girder bridge, suspension bridge, PSC-box-girder bridge, and arch bridge. This paper shows the process of constructing the real-time monitoring system for the arch bridge and the measured result by the system. The arch type among various superstructure types has not only the structural efficiency but the visual beauty, because the arch type superstructure makes full use of the feature of curve. The main measuring points of arch bridges composited by curved members make a difference to compare with the system of girder bridges composited by straight members. This paper also shows the method to construct the monitoring system that considers the characteristic of the arch bridge. The system now includes strain gauges and thermometers, and it will include various sensor types such as CCTV, accelerometers and so on additionally. For the long term and accuracy monitoring, the latest optical sensors and equipments are applied to the system.

Developmental feature of the lumbosacral vertebral arch in childhood

International Nuclear Information System (INIS)

Yoshifuji, Kazuhisa; Morota, Nobuhito; Ihara, Satoshi

2007-01-01

We investigated a developmental feature of the lumbosacral vertebral arch in childhood that has rarely been reported previously. Sixty-seven patients underwent functional posterior rhizotomy from September 2000 to June 2006 at National Center for Child Health and Development. Sixty of these patients, who had no deformity in their lumbosacral spine, were included in this study and their Computed Tomography (CT) images were analyzed retrospectively. There were 36 boys and 24 girls, aged from 2-12 years. The rate and mean number of non-union vertebral arches between L1 and S3 were 78.3% (95% CI, 65.8-87.9%) and 1.7 (standard deviation (SD), 1.3). The non-union arch was most frequently found at the S1 level, and was more significantly observed in the younger age group (2-5 years of age). The S4 and S5 arches, which often remained open as the sacral hiatus, were constantly open in childhood. This study demonstrates that the vertebral arches of the lumbosacral spine in normal development are often not fused during childhood. It is important to differentiate normal non-union arches from pathological spina bifida. (author)

Relationship between psychological well-being and perceptions of stress among undergraduate dental students in Bengaluru city: A cross-sectional study

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M Anushri

2014-01-01

Full Text Available Introduction: The dental profession has been considered a stressful occupation. The origins of this stress may also lie in the process of dental education. The perception of stress is frequently influenced by one′s personal system of beliefs and attitudes. Aim: The aim was to assess the relationship between psychological well-being and perception of stress among undergraduate dental students in Bangalore city. Materials and Methods: A cross-sectional questionnaire survey was conducted among 800 1-4 th year dental students. Information on demographics, social background, and health behaviors were collected. The psychological general well-being (PGWB index and the dental environment stress (DES questionnaire were used to measure PGWB and perceptions of stress, respectively. Multiple intergroup comparisons were carried out using ANOVA. Correlation analysis was done to find out relationship between PGWB and DES. Regression analysis to find out the strongest predictor of PGWB. P <0.05 was considered as statistically significant. Results: There was no significant difference in PGWB among different year of study. Female students had significantly lower PGWB scores and higher DES scores than male students. The stress differed among different year of study with highest stress in final year students in all domains except for clinical/preclinical training, which was highest among 1 st year students. Correlational analysis showed a negative relationship between PGWB and DES score. Stepwise multiple regression analysis revealed that "workload," "patient treatment," "performance pressure" and "others" domains of stress were significant predictors of PGWB. Conclusion: This study revealed that the perception of stress is influenced by gender and health behaviors which in turn affect PGWB.

Child dental anxiety, parental rearing style and dental history reported by parents

NARCIS (Netherlands)

Krikken, J.B.; van Wijk, A.J.; ten Cate, J.M.; Veerkamp, J.S.

2013-01-01

AIM: To examine the relationship between self-reported parental rearing style, parent's assessment of their child's dental anxiety and the dental history of children. MATERIALS AND METHODS: Parents of primary school children were asked to complete questionnaires about their parenting style, using

Transition from failing dentition to full-arch fixed implant-supported prosthesis with a staged approach using removable partial dentures: a case series.

Science.gov (United States)

Cortes, Arthur Rodriguez Gonzalez; Cortes, Djalma Nogueira; No-Cortes, Juliana; Arita, Emiko Saito

2014-06-01

The present retrospective case series is aimed at evaluating a staged approach using a removable partial denture (RPD) as an interim prosthesis in treatment to correct a failing dentition until such time as a full-arch fixed implant-supported prosthesis may be inserted. Eight patients, who had undergone maxillary full-arch rehabilitation with dental implants due to poor prognosis of their dentitions, were analyzed. All treatment included initial periodontal therapy and a strategic order of extraction of hopeless teeth. An RPD supported by selected teeth rehabilitated the compromised arch during implant osseointegration. These remaining teeth were extracted prior to definitive prosthesis delivery. Advantages and drawbacks of this technique were also recorded for the cases presented. Among the advantages provided by the staged approach are simplicity of fabrication, low cost, and ease of insertion. Additionally, RPD tooth support prevented contact between the interim prosthesis and healing abutments, promoting implant osseointegration. The main drawbacks were interference with speech and limited esthetic results. Implant survival rate was 100% within a follow-up of at least 1 year. The use of RPDs as interim prostheses allowed for the accomplishment of the analyzed rehabilitation treatments. It is a simple treatment alternative for patients with a low smile line. © 2013 by the American College of Prosthodontists.

Apert Syndrome: Report of a Case with Emphasis on Oral Manifestations

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B. Vadiati Saberi

2011-06-01

Full Text Available To report the oral findings, including dental anomalies, ectopic eruption of the maxillary permanent first molars and periodontal disease and soft tissue alterations, in a subject with Apert syndrome. Clinical and radiographic examination of a patient with Apert syndrome,aged 21 years old, not previously submitted for orthodontic or orthognathic treatment.Dental anomalies were present in a patient. Intraoral evaluation revealed poor oral hygienewith varying degrees of periodontal involvement, an arched swelling (pseudo cleft configuration,class III malocclusion, anterior open bite, posterior crossbite, supernumerary teeth, ectopic eruption and creamy white enamel opacities, an excessively large appearingtongue and a v-shaped maxillary arch. The occurrence of typical lateral palatal swellings agrees with the literature. The high prevalence of dental anomalies and ectopic eruption may suggest a possible etiologic relationship with the syndrome.

A protocol for classifying normal- and flat-arched foot posture for research studies using clinical and radiographic measurements

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Menz Hylton B

2009-07-01

Full Text Available Abstract Background There are several clinical and radiological methods available to classify foot posture in research, however there is no clear strategy for selecting the most appropriate measurements. Therefore, the aim of this study was to develop a foot screening protocol to distinguish between participants with normal- and flat-arched feet who would then subsequently be recruited into a series of laboratory-based gait studies. Methods The foot posture of ninety-one asymptomatic young adults was assessed using two clinical measurements (normalised navicular height and arch index and four radiological measurements taken from antero-posterior and lateral x-rays (talus-second metatarsal angle, talo-navicular coverage angle, calcaneal inclination angle and calcaneal-first metatarsal angle. Normative foot posture values were taken from the literature and used to recruit participants with normal-arched feet. Data from these participants were subsequently used to define the boundary between normal- and flat-arched feet. This information was then used to recruit participants with flat-arched feet. The relationship between the clinical and radiographic measures of foot posture was also explored. Results Thirty-two participants were recruited to the normal-arched study, 31 qualified for the flat-arched study and 28 participants were classified as having neither normal- or flat-arched feet and were not suitable for either study. The values obtained from the two clinical and four radiological measurements established two clearly defined foot posture groups. Correlations among clinical and radiological measures were significant (p r = 0.24 to 0.70. Interestingly, the clinical measures were more strongly associated with the radiographic angles obtained from the lateral view. Conclusion This foot screening protocol provides a coherent strategy for researchers planning to recruit participants with normal- and flat-arched feet. However, further research is

A survey of U.S. prosthodontists and dental schools on the current materials and methods for final impressions for complete denture prosthodontics.

Science.gov (United States)

Petrie, Cynthia S; Walker, Mary P; Williams, Karen

2005-12-01

The purpose of this study was to survey members of The American College of Prosthodontists (ACP) to evaluate current materials and methods for final impressions for complete denture prosthodontics in the United States. In addition, those methods were compared with methods and materials taught in U.S. dental schools via a second survey sent to the chairpersons of prosthodontic/restorative departments. An anonymous questionnaire was mailed to all 1762 active ACP members in the United States in 2003. A slightly modified questionnaire was also distributed to chairpersons of prosthodontic/restorative departments in the 54 U.S. dental schools. Data analysis was performed via frequency distribution and chi-square statistics. Nine hundred and forty-five questionnaires were returned by members of the ACP (54% return rate) and 42 questionnaires were returned by the U.S. dental schools (78% return rate). The majority of the reporting prosthodontists (88%) and dental schools (98%) use a border-molded custom tray for final impressions for complete denture prosthodontics. The most popular material for border molding was plastic modeling compound (67% of reporting ACP members, and 95% of the responding dental schools). Variability of the materials used for final impressions was observed, with the most popular materials being polyvinylsiloxane for the ACP members (36%) and polysulfide for the dental schools (64%). Statistically significant differences were found in the materials used for border molding by prosthodontists based on the time elapsed since completion of prosthodontic training. No differences were found in the materials used for impression of edentulous arches based on years of experience. Geographic location did not influence the materials and methods used by prosthodontists for complete denture final impressions. There was variability of the materials and techniques used for final impressions by ACP members and dental schools; however, overall there was an agreement

Mechanics Evolution Characteristics Analysis of Pressure-arch in Fully-mechanized Mining Field

Directory of Open Access Journals (Sweden)

S.R. Wang

2014-09-01

Full Text Available Based on a practical engineering, the three-dimension computational model was built using FLAC3D under the fullymechanized mining condition. Considering four variation factors, such as the distance of mining advancing, the strength of the surrounding rock, the speed of mining advancing and the dip angle of the coal seam, the mechanics evolution characteristics of the pressure-arch were analyzed. The result showed that for the horizontal seam, the geometric shape of the pressure-arch varied from flat arch to round arch gradually and the height and thickness of the pressure-arch also increased; the maximum principal stress in the skewback also increased with the working face advancing. With the strength of the surrounding rock from soft to hard, the arch thickness reduced, and the arch loading decreased. To improve the mining speed can do some contributions to the stability of the pressure-arch in the mining field. With the increase of dip angle of the seam, the pressure-arch displayed an asymmetric shape, the vault was tilted and moved to the upward direction. At the same time, the thickness of the pressure-arch increased, and the stress concentration in the skewback tended to be further intensified.

Outcomes of single-stage total arch replacement via clamshell incision

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Ishizaka Toru

2011-09-01

Full Text Available Abstract Background Treatment of complex aortic pathologies involving the transverse arch with extensive involvement of the descending aorta remains a surgical challenge. Since clamshell incision provides superior exposure of the entire thoracic aorta, we evaluated the use of this technique for single-stage total arch replacement by arch vessel reconstruction. Methods The arch-first technique combined with clamshell incision was used in 38 cases of aneurysm and aortic disease in 2008 and 2009. Extensive total arch replacement was used with clamshell incision for reconstruction of arch vessels under deep hypothermic circulatory arrest. Results Overall 30-day mortality was 13%. The mean operating time was approximately 8 hours. Deep hypothermia resulted in mean CPB time exceeding 4.5 hours and mean duration of circulatory arrest was 25 minutes. The overall postoperative temporary and permanent neurologic dysfunction rates were 3% and 3% for elective and 3% and 0% for emergency surgery, respectively. All patients except the five who died in hospital were discharged without nursing care after an average post-operative hospital stay of 35 days. Conclusions The arch-first technique, combined with clamshell incision, provides expeditious replacement of the thoracic aorta with an acceptable duration of hypothermic circulatory arrest and minimizes the risk of retrograde atheroembolism by using antegrade perfusion.

Accuracy of a reformulated fast-set vinyl polysiloxane impression material using dual-arch trays.

Science.gov (United States)

Kang, Alex H; Johnson, Glen H; Lepe, Xavier; Wataha, John C

2009-05-01

A common technique used for making crown impressions involves use of a vinyl polysiloxane impression material in combination with a dual-arch tray. A leading dental manufacturer has reformulated its vinyl polysiloxane (VPS) impression line, but the accuracy of the new material has not been verified. The purpose of this study was to assess the accuracy of reformulated VPS impression materials using the single-step dual-arch impression technique. Dual-arch impressions were made on a typodont containing a master stainless steel standard crown preparation die, from which gypsum working dies were formed, recovered, and measured. The impression materials evaluated were Imprint 3 Penta Putty with Quick Step Regular Body (IP-0); Imprint 3 Penta Quick Step Heavy Body with Quick Step Light Body (IP-1); Aquasil Ultra Rigid Fast Set with LV Fast Set (AQ-1); and Aquasil Ultra Heavy Fast Set with XLV Fast Set (AQ-2) (n=10). All impressions were disinfected with CaviCide spray for 10 minutes prior to pouring with type IV gypsum. Buccolingual (BL), mesiodistal (MD), and occlusogingival (OG) dimensions were measured and compared to the master die using an optical measuring microscope. Linear dimensional change was also assessed for IP-0 and AQ-1 at 1 and 24 hours based on ANSI/ADA Specification No. 19. Single-factor ANOVA with Dunnett's T3 multiple comparisons was used to compare BL, MD, and OG changes, with hypothesis testing at alpha=.05. A repeated-measures ANOVA was used to compare linear dimensional changes. There were statistical differences among the 4 impression systems for 3 of 4 dimensions of the master die. IP-0 working dies were significantly larger in MD and OG-L dimensions but significantly smaller in the BL dimension. IP-1 working dies were significantly smaller in the BL dimension compared to the master die. With the exception of IP-0, differences detected were small and clinically insignificant. No significant differences were observed for linear dimensional change

Super-light pearl-chain arch vaults

DEFF Research Database (Denmark)

Hertz, Kristian Dahl; Halding, Philip Skov

2014-01-01

Arch vaults are known as optimal and impressive structures, but due to their curved shapes they are extremely costly to produce in countries, where the cost of labor is high. By means of super-light pearl-chain technology arch vaults can be constructed from equal plane prefabricated elements, which...... that it is also applicable as basic elements for super-light pearl-chain vaults. Machines and software have been developed for automatic mass production of the elements, and the first factory has started production in Denmark in 2014 delivering SL-deck elements for a variety of building projects. This means...... is known from curved voluminous elements. The paper describes the first full-scale test of an arch vault made of SL-deck elements demonstrating the principle, documenting the load-bearing capacity, and solving a number of details needed in order to create vaults in practice. Considerations and plans...

Panoramic dental radiography image intensification employing minification techniques

International Nuclear Information System (INIS)

Cushman, R.H.

1981-01-01

Panoramic dental x-ray machine wherein an x-ray source-camera assembly orbits a seated patient is described. A slot in the camera assembly collimates the x-rays which are continuously generated by the x-ray source, which x-rays are converted to light images of the patient's dental arch structure by only a single intensifying screen which remains stationary. This screen comprises about 1/40 the area of conventional intensifying screens and is made thicker for providing improved detection efficiency. A fiber optic minifying lens reduces the size of the image from the screen while proportionately increasing the light intensity of the image, thus making it possible to provide useable film images at reduced x-ray exposures due to non-linear film exposure versus optical density characteristics. The resultant minified, light-intensified image may now be recorded on 35 mm roll film, for example, as opposed to standard radiographic film of 5'' X 12'' size, or 12.70 cm X 30.48 cm

Plastic collapse load of crown-hinged steel circular arches : a theoretical method

NARCIS (Netherlands)

Spoorenberg, R.C.; Snijder, H.H.; Hoenderkamp, J.C.D.

2013-01-01

For construction purposes and to avoid detrimental influences of foundation settlements arches are not always made from a single arch-rib but are built by connecting two curvilinear elements at the crown with a hinge. These arches are also known as crown-hinged arches. This paper presents an

Agenesis of the posterior arch of the atlas

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Torriani Martin

2002-01-01

Full Text Available PURPOSE: To illustrate the radiological findings and review the current literature concerning a rare congenital abnormality of the posterior arch of the atlas. CASE REPORT: An adult female without neurological symptoms presented with an absent posterior arch of the atlas, examined with plain films and helical computerized tomography. Complete agenesis of the posterior arch of the atlas is a rare entity that can be easily identified by means of plain films. Although it is generally asymptomatic, atlantoaxial instability and neurological deficits may occur because of structural instability. Computerized tomography provides a means of assessing the extent of this abnormality and can help evaluate the integrity of neural structures. Although considered to be rare entities, defects of the posterior arch of the atlas may be discovered as incidental asymptomatic findings in routine cervical radiographs. Familiarity with this abnormality may aid medical professionals in the correct management of these cases.

Impact of Removable Partial Dental Prostheses on the Oral Health-Related Quality of Life of a South African Cohort with Varied Distributions of Missing Posterior Teeth.

Science.gov (United States)

Khan, Sadika; Chikte, Usuf; Omar, Ridwaan

2017-10-25

To determine the impact of removable partial dental prostheses on satisfying the daily functioning and quality of life (QoL) of adult patients with different distributions of missing posterior teeth. A cross-sectional interventional study was carried out on 80 patients having variously distributed posteriorly shortened and interrupted arches. Treatment comprised provision of partial dentures by senior dental students, supervised by senior clinical teachers who had knowledge of the potential benefits of the shortened dental arch (SDA) concept. The Oral Impacts on Daily Performance Index was completed before and 6 months after prosthetic treatment across groups comprising Kennedy Classes I, II, and III arches. Analysis included descriptive statistics and associations and comparisons between variables. Mean age of patients was 57.4 years (SD = 13.1), many were retired (72.2%), and a majority were females (60%). Most patients lived in urban areas (95%), and were largely unemployed (63.3%). At pretreatment, only 31.3% of patients reported having good dental health and satisfaction with their current oral state, while 82.5% said they had a great need for treatment. The negative oral impacts that were most frequently experienced were those of eating (67.5%), smiling (50%), and being emotionally disturbed (63.8%). Post-treatment, 76.3% indicated good oral health and satisfaction with no significant differences between the 3 Kennedy groups. Any further negative impacts were reported mostly for Kennedy Classes I and II. Overall, significant reductions of negative impacts were observed following treatment with dentures, across the 3 Kennedy groups, with respect to improved function, satisfaction, and oral health-related QoL. The findings confirm the reliance by partially dentate patients in all 3 Kennedy groups on dentures for improved oral health, although the possible benefits of the SDA concept as an alternative treatment option was not specifically explored. © 2017 by

A case of complete double aortic arch visualized by transthoracic echocardiography.

Science.gov (United States)

Saito, Naka; Kato, Shingo; Saito, Noritaka; Nakachi, Tatsuya; Fukui, Kazuki; Iwasawa, Tae; Kosuge, Masami; Kimura, Kazuo

2017-08-01

A case of double aortic arch that was well visualized using transthoracic echocardiography is reported. A 38-year-old man underwent transthoracic echocardiography for the evaluation of dyspnea. A suprasternal view of transthoracic echocardiography showed the ascending aorta bifurcate to left and right aortic arches, with blood flow from the ascending aorta to bilateral aortic arches. The diagnosis of right side-dominant double aortic arch was made, and the patient's symptom was conceivably related to compression of the trachea due to a vascular ring. This report indicates the potential usefulness of transthoracic echocardiography for noninvasive detection of double aortic arch in adults. © 2017, Wiley Periodicals, Inc.

The arches of the Sanctuary of Loyola. The relationship between the Roman project and Spanish building techniques

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Iacopo Benincampi

2015-12-01

Full Text Available The ascent to the throne of Spain in 1714 by Philip V of Bourbon ended the War of the Spanish Succession, and opened a new period of peace and prosperity that is reflected mainly in the building sites sponsored by the Crown, including also the factory of the Sanctuary of Loyola, which restarted the construction under the leadership of Sebastian Lecuna, who was in charge of raising the circular church. However, the complexity of the project, edited by Carlo Fontana and sent from Rome in 1686, and the changes already made in the plant imposed a careful preliminary reflection which resulted in 1719 in a consultation which was attended by the former director of the factory, Martin de Zaldua, the theoretical Benedictine Pedro Martinez de Cardeña and the Salamanca Cathedral master mayor Joaquin de Churriguera. The masters were contacted to express their opinion about the construction of the vaults of the nave ring, the decoration and especially on the most suitable form to be assigned to the arches of the church, a subject of great interest cause of their uniqueness and complexity. In this sense, the loss of the original drawings do not allow a proper understanding neither of the proposals submitted or the final solution adopted but, nevertheless, a careful study of archival records and the reconstruction of the stereotomic geometry underlies these arches now has led to new contributions, which are useful to a greater general understanding of the factory. Keywords: Loyola, Stereotomy, Carlo Fontana, Sebastian Lecuna, arches

Comparative study on the mechanical mechanism of confined concrete supporting arches in underground engineering.

Science.gov (United States)

Lv, Zhijin; Qin, Qian; Jiang, Bei; Luan, Yingcheng; Yu, Hengchang

2018-01-01

In order to solve the supporting problem in underground engineering with high stress, square steel confined concrete (SQCC) supporting method is adopted to enhance the control on surrounding rocks, and the control effect is remarkable. The commonly used cross section shapes of confined concrete arch are square and circular. At present, designers have no consensus on which kind is more proper. To search for the answer, this paper makes an analysis on the mechanical properties of the two shapes of the cross-sections. A full-scale indoor comparative test was carried out on the commonly used straight-wall semi-circular SQCC arch and circular steel confined concrete arch (CCC arch). This test is based on self-developed full-scale test system for confined concrete arch. Our research, combining with the numerical analysis, shows: (1) SQCC arch is consistent with CCC arch in the deformation and failure mode. The largest damages parts are at the legs of both of them. (2) The SQCC arch's bearing capability is 1286.9 kN, and the CCC arch's ultimate bearing capability is 1072.4kN. Thus, the SQCC arch's bearing capability is 1.2 times that of the CCC arch. (3) The arches are subjected to combined compression and bending, bending moment is the main reason for the arch failure. The section moment of inertia of SQCC arch is 1.26 times of that of CCC arch, and the former is better than the latter in bending performance. The ultimate bearing capacity is positively correlated with the size of the moment of inertia. Based on the above research, the engineering suggestions are as follows: (1) To improve the bearing capacity of the arch, the cross-sectional shape of the chamber should be optimized and the arch bearing mode changed accordingly. (2) The key damaged positions, such as the arch leg, should be reinforced, optimizing the state of force on the arch. SQCC arches should be used for supporting in underground engineering, which is under stronger influence of the bending moment and

[To bite or to scan? Dental impressions with alginate, PVS or -intra-oral scanning; processing time and patient comfort. A pilotstudy].

Science.gov (United States)

Darroudi, M; Ariens, Z P A; Zinsmeister, V Z; Breuning, K H

2017-02-01

In recent years technology has enabled dental professionals to make digital dental models using intra-oral scanners. In a study involving 10 test cases, a comparison was made between the digital impression technique and 2 -conventional impression techniques, using alginate and Polivinyl Syloxane™. With the 3 different techniques, dental impressions were made of the lower and upper arches; the processing time required for each and the differences in patient comfort were recorded. The individuals in the test cases experienced no difference in comfort between the alginate and the digital impression. The impression technique involving Polivinyl Syloxane™ was experienced as less comfortable. The digital impression technique appeared to be the most time consuming.

Relationship Between Carotid Artery Calcification Detected in Dental Panoramic Images and Hypertension and Myocardial Infarction

International Nuclear Information System (INIS)

Moshfeghi, Mahkameh; Taheri, Jamileh Beigom; Bahemmat, Nika; Evazzadeh, Mohammad Ebrahim; Hadian, Hoora

2014-01-01

Carotid artery calcification may be related to cerebrovascular accident, which may result in death or physical and mental disabilities in survivors. Our purpose is to study the association of carotid artery calcification (CAC) on dental panoramic radiographs and two risk factors of cerebrovascular accident (CVA) including hypertension and myocardial infarction (MI). Panoramic images of 200 patients that were all women above 50 years of age (a population suffering from vascular diseases) were investigated. All panoramic images were provided under similar conditions in terms of the type of panoramic radiograph equipment, type of applied films and the automatic film processor. Then, the patients answered questions about MI history and taking antihypertensive drugs. We also measured the blood pressure of patients in two separate surveys. Data analysis was performed by SPSS statistical program. We used Exact Fisher test and Chi-Square test at a significant level of less than 0.05 to study the effect of these variables on the occurrence of carotid artery calcification. Among 200 studied samples, 22 of the patients (11%) had carotid artery calcification on the dental panoramic radiograph. In total, 52 patients (26%) had hypertension and four people (2%) had a history of MI. Eleven individuals among patients suffering from hypertension (21.2%) and three individuals among patients with a history of MI (75%) demonstrated CAC on dental panoramic images . The relationship between CAC found on dental panoramic radiographs and two CVA risk factors--hypertension and MI-- was significant. Therefore, it seems that detection of CAC on panoramic images of dental patients must be considered by dentists

Does dental caries affect dental development in children and adolescents?

Science.gov (United States)

Dhamo, Brunilda; Elezi, Besiana; Kragt, Lea; Wolvius, Eppo B; Ongkosuwito, Edwin M

2018-01-01

Although a link between dietary changes, caries, and dental development has been observed, the literature provides little insight about this relationship. The aim of our study was to investigate the association between dental caries and dental development in a clinical sample of Albanian children and adolescents. In total, 118 children and adolescents, born between 1995 and 2004 and aged 6–15 years, were included. Dental caries in the deciduous dentition was assessed using the Decayed, Filled Teeth (dft) index and dental caries in the permanent dentition was assessed using the Decayed, Missing, Filled Teeth (DMFT) index. Dental development during the permanent dentition was determined using the Demirjian method. Linear and ordinal regression models were applied to analyze the associations of dental caries with dental age and developmental stages of each left mandibular tooth. Dental caries in the deciduous dentition, estimated as a median dft of 2.0 (90% range, 0.0–9.1), was significantly associated with lower dental age (β = -0.21; 90% CI: -0.29, -0.12) and with delayed development of the canine, both premolars, and the second molar. Untreated dental caries (dt) was associated with lower dental age (β = -0.19; 90% CI: -0.28, -0.10). Dental caries in the permanent dentition, estimated as a median DMFT of 1.0 (90% range, 0.0–8.0), was not significantly associated with dental age (β = 0.05; 90% CI: -0.04, 0.14). However, the DMFT was associated with the advanced stages of development of both premolars and the second molar. The untreated dental caries in the deciduous dentition delays the development of permanent teeth. PMID:29659350

Posttreatment quantification of patient experiences with full-arch implant treatment using a modification of the OHIP-14 questionnaire.

Science.gov (United States)

Babbush, Charles A

2012-06-01

Patient well-being is always the goal of rehabilitation of edentulism; however, evaluations of treatment success often overlook the patient's subjective feelings about comfort, function, speech, social image, social inhibitions, psychological discomfort, and/or disabilities. The purpose of this study was to assess these patient responses using an oral health questionnaire. To assess such feelings, a self-administered 20-question multiple-choice patient-reported Edentulous Patient Impact Questionnaire was developed, based upon the previously validated Oral Health Impact Profile patient-assessment tool. Responses were solicited from randomly selected patients treated with an implant-supported, fixed, immediately loaded full arch prosthesis. The questionnaires were completed by 250 patients. Of the respondents, 95% described themselves as being either extremely satisfied (74%) or satisfied (21%) with their new teeth, and 98% said they would definitely recommend similar treatment (88%) or consider recommending it (10%) to a friend or colleague. Based upon an oral health impact survey completed by 250 patients treated with full-arch implant-supported, immediately loaded fixed dental prostheses, it appears that patient satisfaction is high and that treated patients would generally be willing to recommend this treatment to others.

Level-ARCH Short Rate Models with Regime Switching

DEFF Research Database (Denmark)

Christiansen, Charlotte

This paper introduces regime switching volatility into level- ARCH models for the short rates of the US, the UK, and Germany. Once regime switching and level effects are included there are no gains from including ARCH effects. It is of secondary importance exactly how the regime switching is spec...

A comparison of foot kinematics in people with normal- and flat-arched feet using the Oxford Foot Model.

Science.gov (United States)

Levinger, Pazit; Murley, George S; Barton, Christian J; Cotchett, Matthew P; McSweeney, Simone R; Menz, Hylton B

2010-10-01

Foot posture is thought to influence predisposition to overuse injuries of the lower limb. Although the mechanisms underlying this proposed relationship are unclear, it is thought that altered foot kinematics may play a role. Therefore, this study was designed to investigate differences in foot motion between people with normal- and flat-arched feet using the Oxford Foot Model (OFM). Foot posture in 19 participants was documented as normal-arched (n=10) or flat-arched (n=9) using a foot screening protocol incorporating measurements from weightbearing antero-posterior and lateral foot radiographs. Differences between the groups in triplanar motion of the tibia, rearfoot and forefoot during walking were evaluated using a three-dimensional motion analysis system incorporating a multi-segment foot model (OFM). Participants with flat-arched feet demonstrated greater peak forefoot plantar-flexion (-13.7° ± 5.6° vs -6.5° ± 3.7°; p=0.004), forefoot abduction (-12.9° ± 6.9° vs -1.8° ± 6.3°; p=0.002), and rearfoot internal rotation (10.6° ± 7.5° vs -0.2°± 9.9°; p=0.018) compared to those with normal-arched feet. Additionally, participants with flat-arched feet demonstrated decreased peak forefoot adduction (-7.0° ± 9.2° vs 5.6° ± 7.3°; p=0.004) and a trend towards increased rearfoot eversion (-5.8° ± 4.4° vs -2.5° ± 2.6°; p=0.06). These findings support the notion that flat-arched feet have altered motion associated with greater pronation during gait; factors that may increase the risk of overuse injury. Copyright © 2010 Elsevier B.V. All rights reserved.

Previous toothache, dental visits and caries presence among ...

African Journals Online (AJOL)

Background: Dental pain is an ache or soreness within or around a tooth. It has a wide range of etiology, the commonest being dental caries. Dental pain is one of the main reasons for seeking dental care. Objectives: To assess the relationship between experiences of toothache, dental visits and caries experience among ...

Perception of Nepalese dental hygiene and dentistry students towards the dental hygienists profession.

Science.gov (United States)

Knevel, Rjm; Gussy, M G; Farmer, J; Karimi, L

2017-08-01

This study investigates student and stakeholder perceptions of the role of the dental hygienist in Nepal. The impact of these perceptions on the professionalization of dental hygienists is described whilst exploring the consequences for oral health workforce planning. Dentistry and dental hygiene students from one dental college in Nepal were asked to complete an anonymous questionnaire; 171 students returned the questionnaire containing a mix of forced response and open-ended items. Quantitative data were analysed using SPSS ® 22. These data were complemented with qualitative information from survey open questions and from semi-structured interviews with key informants from several relevant organizations. Qualitative data were manually analysed and coded. Data were triangulated to contextualize quantitative data. A high level of positive regard for the role of the dental hygienist in Nepal was evident amongst dentistry and dental hygiene students in this college. Both groups believe that the dental hygienist can play a major role in raising oral health awareness in Nepal. The scope of practice of the dental hygienist was unclear with issues surrounding the scope of practice and reports of illegal practice by dental hygienists. Significant differences (P dental hygiene and dentistry students in relation to their opinion regarding independent practice and the need of supervision by a dentist. Supervision of the dental hygienist by dentists and issues surrounding the scope of practice are polarizing the relationship between dentists, dental hygienists and the relevant professional organizations. This could hinder cooperation between these oral health professionals and might lead to underutilization of the dental hygienist. To improve the understanding about the roles of each oral health professional, establishing functional relationships and intraprofessional education involving dentistry and dental hygiene students needs to be introduced. This will benefit the

The relationship of forensic odontology with various dental specialties in the articles published in the Journal of Forensic odonto-stomatology from 2005 to 2012.

Science.gov (United States)

Shamim, Thorakkal

2015-01-01

There is a paucity of information about the relationship of forensic odontology with various dental specialties in the articles published in the Journal of Forensic Odonto-Stomatology. This study aimed to find the relationship of forensic odontology with various dental specialties in the articles published in the Journal of Forensic Odonto-Stomatology from 2005 to 2012 over an 8-year period. Bibliometric analysis was performed using web-based search during December 2013. Out of the total 97 published articles, the maximum number of published articles were related to oral medicine and radiology (20) and community dentistry (20), followed by orthodontics (18), prosthodontics (15), and oral pathology and microbiology (8), pedodontics (7), oral and maxillofacial surgery (4) and conservative dentistry and endodontics (3). Among the articles published in Journal of Forensic Odonto-Stomatology, mass disasters (10) and bite mark analysis (10), followed by sexual dimorphism (8) and dental fraud and malpractice (8), followed by craniofacial superimposition (6) and identification (6) form the major attraction of the contributors. This paper has tried to evaluate the new working classification proposed for forensic odontology based on its relationship with other dental specialties.

In vivo Study of the Accuracy of Dual-arch Impressions.

Science.gov (United States)

de Lima, Luciana Martinelli Santayana; Borges, Gilberto Antonio; Junior, Luiz Henrique Burnett; Spohr, Ana Maria

2014-06-01

This study evaluated in vivo the accuracy of metal (Smart®) and plastic (Triple Tray®) dual-arch trays used with vinyl polysiloxane (Flexitime®), in the putty/wash viscosity, as well as polyether (Impregum Soft®) in the regular viscosity. In one patient, an implant-level transfer was screwed on an implant in the mandibular right first molar, serving as a pattern. Ten impressions were made with each tray and impression material. The impressions were poured with Type IV gypsum. The width and height of the pattern and casts were measured in a profile projector (Nikon). The results were submitted to Student's t-test for one sample (α = 0.05). For the width distance, the plastic dual-arch trays with vinyl polysiloxane (4.513 mm) and with polyether (4.531 mm) were statistically wider than the pattern (4.489 mm). The metal dual-arch tray with vinyl polysiloxane (4.504 mm) and with polyether (4.500 mm) did not differ statistically from the pattern. For the height distance, only the metal dual-arch tray with polyether (2.253 mm) differed statistically from the pattern (2.310 mm). The metal dual-arch tray with vinyl polysiloxane, in the putty/wash viscosities, reproduced casts with less distortion in comparison with the same technique with the plastic dual-arch tray. The plastic or metal dual-arch trays with polyether reproduced cast with greater distortion. How to cite the article: Santayana de Lima LM, Borges GA, Burnett LH Jr, Spohr AM. In vivo study of the accuracy of dual-arch impressions. J Int Oral Health 2014;6(3):50-5.

The effect of impression volume and double-arch trays on the registration of maximum intercuspation.

Science.gov (United States)

Hahn, Sara M; Millstein, Philip L; Kinnunen, Taru H; Wright, Robert F

2009-12-01

The type of double-arch trays used may affect occlusion. The purpose of this study was to determine what effect, if any, double-arch tray design and impression material volume had on the registration of maximum intercuspation (MI). Quadrant impressions were made on articulated fracture-resistant dental casts mounted in maximum intercuspation occlusion. Three types of sideless double-arch impression trays were used: First Bite with nylon webbing, Sultan's 3-Way with double crosshatch webbing, and Premium's 3-in-1 Tray with single crosshatch webbing. Vinyl polysiloxane impression material (Aquasil Ultra Rigid Fast Set) was distributed at 2 different volumes (5.4 ml and 8.3 ml), and 60 impressions were made (n=10). A weight of 1.2 kg was placed on the upper arm of an Artex articulator, ensuring complete closure. The impressions were allowed to polymerize for 5 minutes. After polymerization, specimens were placed on a light box, and a camera set at a fixed distance was used to capture the light transmission that was projected through the impression material. The camera transferred the information to an image analysis program (ImageJ). This system allowed the different amounts of light projected through the impression to be translated into a gray scale value (GSV), which was assigned a thickness value, in millimeters, of a specified occlusal contact area. To assess reliability of the experimental design, 10 control impressions were made by directly applying impression material onto the typodont. These were analyzed in the same manner as the impressions made with trays. A 2-way ANOVA comparing volume by tray type was used (alpha=.05). This was followed by a Tukey HSD test. There was no main effect for volume of impression material (P=.71). Tray type was significantly different (Precord making.

HSPG-deficient zebrafish uncovers dental aspect of multiple osteochondromas.

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Malgorzata I Wiweger

Full Text Available Multiple Osteochondromas (MO; previously known as multiple hereditary exostosis is an autosomal dominant genetic condition that is characterized by the formation of cartilaginous bone tumours (osteochondromas at multiple sites in the skeleton, secondary bursa formation and impingement of nerves, tendons and vessels, bone curving, and short stature. MO is also known to be associated with arthritis, general pain, scarring and occasional malignant transformation of osteochondroma into secondary peripheral chondrosarcoma. MO patients present additional complains but the relevance of those in relation to the syndromal background needs validation. Mutations in two enzymes that are required during heparan sulphate synthesis (EXT1 or EXT2 are known to cause MO. Previously, we have used zebrafish which harbour mutations in ext2 as a model for MO and shown that ext2⁻/⁻ fish have skeletal defects that resemble those seen in osteochondromas. Here we analyse dental defects present in ext2⁻/⁻ fish. Histological analysis reveals that ext2⁻/⁻ fish have very severe defects associated with the formation and the morphology of teeth. At 5 days post fertilization 100% of ext2⁻/⁻ fish have a single tooth at the end of the 5(th pharyngeal arch, whereas wild-type fish develop three teeth, located in the middle of the pharyngeal arch. ext2⁻/⁻ teeth have abnormal morphology (they were shorter and thicker than in the WT and patchy ossification at the tooth base. Deformities such as split crowns and enamel lesions were found in 20% of ext2⁺/⁻ adults. The tooth morphology in ext2⁻/⁻ was partially rescued by FGF8 administered locally (bead implants. Our findings from zebrafish model were validated in a dental survey that was conducted with assistance of the MHE Research Foundation. The presence of the malformed and/or displaced teeth with abnormal enamel was declared by half of the respondents indicating that MO might indeed be also associated

The vicious cycle of dental fear: exploring the interplay between oral health, service utilization and dental fear

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Spencer A John

2007-01-01

Full Text Available Abstract Background Based on the hypothesis that a vicious cycle of dental fear exists, whereby the consequences of fear tend to maintain that fear, the relationship between dental fear, self-reported oral health status and the use of dental services was explored. Methods The study used a telephone interview survey with interviews predominantly conducted in 2002. A random sample of 6,112 Australian residents aged 16 years and over was selected from 13 strata across all States and Territories. Data were weighted across strata and by age and sex to obtain unbiased population estimates. Results People with higher dental fear visited the dentist less often and indicated a longer expected time before visiting a dentist in the future. Higher dental fear was associated with greater perceived need for dental treatment, increased social impact of oral ill-health and worse self-rated oral health. Visiting patterns associated with higher dental fear were more likely to be symptom driven with dental visits more likely to be for a problem or for the relief of pain. All the relationships assumed by a vicious cycle of dental fear were significant. In all, 29.2% of people who were very afraid of going to the dentist had delayed dental visiting, poor oral health and symptom-driven treatment seeking compared to 11.6% of people with no dental fear. Conclusion Results are consistent with a hypothesised vicious cycle of dental fear whereby people with high dental fear are more likely to delay treatment, leading to more extensive dental problems and symptomatic visiting patterns which feed back into the maintenance or exacerbation of existing dental fear.

Deformation Monitoring of Geomechanical Model Test and Its Application in Overall Stability Analysis of a High Arch Dam

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Baoquan Yang

2015-01-01

Full Text Available Geomechanical model testing is an important method for studying the overall stability of high arch dams. The main task of a geomechanical model test is deformation monitoring. Currently, many types of deformation instruments are used for deformation monitoring of dam models, which provide valuable information on the deformation characteristics of the prototype dams. However, further investigation is required for assessing the overall stability of high arch dams through analyzing deformation monitoring data. First, a relationship for assessing the stability of dams is established based on the comprehensive model test method. Second, a stability evaluation system is presented based on the deformation monitoring data, together with the relationships between the deformation and overloading coefficient. Finally, the comprehensive model test method is applied to study the overall stability of the Jinping-I high arch dam. A three-dimensional destructive test of the geomechanical model dam is conducted under reinforced foundation conditions. The deformation characteristics and failure mechanisms of the dam abutments and foundation were investigated. The test results indicate that the stability safety factors of the dam abutments and foundation range from 5.2 to 6.0. These research results provide an important scientific insight into the design, construction, and operation stages of this project.

The relationship between study skill and academic achievement in dental students of Tehran University of Medical Sciences

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Shirazian Shiva

2015-12-01

Full Text Available Background and Aims: The purpose of the present study was to investigate the relationship between study skills and academic performance of dental students in Tehran University of Medical Sciences. Materials and Methods: 195 dental students at dental faculty of Tehran University of Medical Sciences in 2013 participated in this descriptive-analytical study. Data were collected using Congos´ Study Skills Inventory including six subscales. Grade Point Average (GPA indicated their academic performance. Data were analyzed using ANOVA and Tukey test. Results: The mean score of students’ study skills were 108 out of 200 with standard deviation of 22.06±0.7. Note taking had a significant correlation with GPA (P=0.015. Conclusion: Since no significant correlation between study skills and academic performance of the students was observed, it seems that there are other dynamics involved in their academic performance which have to be examined.

True tracheal bronchus: Classification and anatomical relationship on multi-detector computed tomography

International Nuclear Information System (INIS)

Kim, Hyun Jeong; Kim, Young Tong; Jou, Sung Shick; Lee, Woong Hee

2017-01-01

To propose the imaging classification of true tracheal bronchus (TTB) on multi-detector computed tomography (MDCT), and to evaluate its anatomical relationship with surrounding structures. This study included 44 patients who were diagnosed with TTB on MDCT for 6 years. We classified TTB into five types, based on the existence of the right upper lobe bronchus originating from the right main bronchus and the number of segmental bronchi of TTB. We analyzed the site of origin and the running direction of TTB based on its anatomical relationship with surrounding structures and some ancillary findings. The imaging classification of TTB included Type I (47.7%), Type II (13.6%), Type III (11.4%), Type IV (25.0%), and Type V (2.0%). According to the site of origin of TTB, below the aortic arch (52.3%) and at the level of the aortic arch (43.1%) were the two main sites of origin, whereas the frequency of the site of origin above the azygos arch, at the level of the azygos arch, and below the azygos arch was 27.3%, 38.6%, and 34.1%, respectively. Considering both aortic and azygos arches, below the aortic arch and below the azygos arch were the most common sites of origin (27.3%). With respect to the running direction of TTB, in all cases, TTB passed below the azygos arch to the right upper lobe. There was no statistically significant (p > 0.05) difference in age or sex between types of TTB. Ancillary findings included tracheal stenosis (n = 2), narrowing of the right main bronchus (n = 2), luminal narrowing of TTB and bronchiectasis at the distal portion (n = 1), and a highly located azygos arch above the aortic arch (n = 2). The proposed imaging classification of TTB and its anatomical relationship with surrounding structures will improve our understanding of various imaging features and embryological development of TTB. Radiologists should pay careful attention to evaluation of the airway including the trachea on thoracic imaging

True tracheal bronchus: Classification and anatomical relationship on multi-detector computed tomography

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Jeong; Kim, Young Tong; Jou, Sung Shick; Lee, Woong Hee [Dept. of Radiology, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan (Korea, Republic of)

2017-04-15

To propose the imaging classification of true tracheal bronchus (TTB) on multi-detector computed tomography (MDCT), and to evaluate its anatomical relationship with surrounding structures. This study included 44 patients who were diagnosed with TTB on MDCT for 6 years. We classified TTB into five types, based on the existence of the right upper lobe bronchus originating from the right main bronchus and the number of segmental bronchi of TTB. We analyzed the site of origin and the running direction of TTB based on its anatomical relationship with surrounding structures and some ancillary findings. The imaging classification of TTB included Type I (47.7%), Type II (13.6%), Type III (11.4%), Type IV (25.0%), and Type V (2.0%). According to the site of origin of TTB, below the aortic arch (52.3%) and at the level of the aortic arch (43.1%) were the two main sites of origin, whereas the frequency of the site of origin above the azygos arch, at the level of the azygos arch, and below the azygos arch was 27.3%, 38.6%, and 34.1%, respectively. Considering both aortic and azygos arches, below the aortic arch and below the azygos arch were the most common sites of origin (27.3%). With respect to the running direction of TTB, in all cases, TTB passed below the azygos arch to the right upper lobe. There was no statistically significant (p > 0.05) difference in age or sex between types of TTB. Ancillary findings included tracheal stenosis (n = 2), narrowing of the right main bronchus (n = 2), luminal narrowing of TTB and bronchiectasis at the distal portion (n = 1), and a highly located azygos arch above the aortic arch (n = 2). The proposed imaging classification of TTB and its anatomical relationship with surrounding structures will improve our understanding of various imaging features and embryological development of TTB. Radiologists should pay careful attention to evaluation of the airway including the trachea on thoracic imaging.

Child dental anxiety, parental rearing style and dental history reported by parents.

Science.gov (United States)

Krikken, J B; Vanwijk, A J; Tencate, J M; Veerkamp, J S

2013-12-01

To examine the relationship between self-reported parental rearing style, parent's assessment of their child's dental anxiety and the dental history of children. Parents of primary school children were asked to complete questionnaires about their parenting style, using four different questionnaires. Parents also completed the Child Fear Survey Schedule Dental Subscale (CFSS-DS) on behalf of their child and a questionnaire about the dental history of their child. 454 interview forms were available for analysis. Minor associations were found between dental anxiety and parenting style. Anxious parents were more permissive and less restrictive in their parenting style. Parents of children who did not visit their dentist for regular check-ups reported more laxness and less restrictiveness. Children who had a cavity at the time of investigation, children who had suffered from toothache in the past and children who did not have a nice and friendly dentist reported more dental anxiety. No clear associations between parenting style and dental anxiety were found. Known causes of dental anxiety were confirmed.

First Branchial Arch Fistula: A Rarity and a Surgical Challenge.

Science.gov (United States)

Rajkumar, J S; Ganesh, Deepa; Anirudh, J R; Akbar, S; Joshi, Niraj

2016-06-01

Although 2(nd) Branchial arch fistulae (from incomplete closure of Cervical sinus of His) are well known, 1(st) arch fistulae are much rarer (branchial arch fistula of the type II Arnot classification, which presented with two external openings of more than 20 years duration. Patient had a successful resection of all the concerned fistulous tract. Review of literature and the surgical challenges of the procedure are presented herewith.

Decoronation followed by dental implants placement: fundamentals, applications and explanations

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Consolaro, Alberto; Ribeiro, Paulo Domingos; Cardoso, Maurício A.; Miranda, Dario A. Oliveira; Salfatis, Monica

2018-01-01

ABSTRACT Dental arches areas with teeth presenting dentoalveolar ankylosis and replacement root resorption can be considered as presenting normal bone, in full physiological remodeling process; and osseointegrated implants can be successfully placed. Bone remodeling will promote osseointegration, regardless of presenting ankylosis and/or replacement root resorption. After 1 to 10 years, all dental tissues will have been replaced by bone. The site, angulation and ideal positioning in the space to place the implant should be dictated exclusively by the clinical convenience, associated with previous planning. One of the advantages of decoronation followed by dental implants placement in ankylosed teeth with replacement resorption is the maintenance of bone volume in the region, both vertical and horizontal. If possible, the buccal part of the root, even if thin, should be preserved in the preparation of the cavity for the implant, as this will maintain gingival tissues looking fully normal for long periods. In the selection of cases for decoronation, the absence of microbial contamination in the region - represented by chronic periapical lesions, presence of fistula, old unconsolidated root fractures and active advanced periodontal disease - is important. Such situations are contraindications to decoronation. However, the occurrence of dentoalveolar ankylosis and replacement resorption without contamination should neither change the planning for implant installation, nor the criteria for choosing the type and brand of dental implant to be used. Failure to decoronate and use dental implants has never been reported. PMID:29791693

Dental health status and treatment needs of transport workers of a northern Indian city: A cross-sectional study

Science.gov (United States)

Gambhir, Ramandeep S.; Sogi, Girish M.; Veeresha, Koratagere Lingappa; Sohi, Ramandeep K.; Randhawa, Amaninder; Kakar, Heena

2013-01-01

Aim: To assess the dental health status and treatment needs of transport workers working in Chandigarh Transport Undertaking (C.T.U.) buses, Chandigarh. Materials and Methods: A cross-sectional study was conducted on all the available C.T.U. workers at all three bus depots. The data were recorded on a modified W.H.O. format (1997). A total of 1008 subjects constituted the final sample size. Results: The mean age of the subjects was 45.3 ± 7.8 years, and 97% (978) were males. Prevalence of dental caries was 63.4% and mean DMFT was 5.02. 47.6% of subjects needed some prosthesis in the maxillary arch while 53.3% needed some prosthesis in the mandibular arch. Regarding highest CPI (Community Periodontal Index) score, 8.13% of the subjects had healthy periodontium while maximum subjects (73.2%) had a score 2 (Calculus). Conclusion: Mean DMFT (Decayed, Missing and Filled Teeth) was satisfactory. Prosthetic need of the subjects was high with only a few subjects possessing prosthesis. Advanced periodontal disease (CPI score, 4) affected small number of subjects with maximum subjects (73%) having a CPI score of 2. PMID:24082750

The Evaluation of Relationship between Spirometric Disorders and Methyl methacrylate in Dental Laboratories Personnel

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E. Nadi

2010-04-01

Full Text Available Introduction & Objective: Methyl methacrylate (MMA, as a monomer of acrylic resin that has a wide variety of usages in denture fabrication, is considered as an air pollution indicator in the laboratories. Occupational exposure to these compound vapors can cause respiratory hypersensitivity, occupational asthma, eye and skin irritation and Allergic Contact Dermatitis (ACD. Therefore control of MMA exposure may promote the personnel’s health. The aim of this study was to determine the relationship between spirometric disorders and methyl methacrylate in dental laboratories personnel.. Materials & Methods: In this case control study, exposure of time-weighted average (TWA and short-term exposure level (STEL were measured with MMA vapors in 39 randomly selected male employee (case group in 25 denture fabrication laboratories in Hamadan city. The air samples were collected by sorbent tubes containing chromosorb (XAD2( and analyzed by gas chromatograph equipped with FID detector based on NIOSH method. In addition 30 men whitout occupational exposure to air pollutants (control group were selected to compare the variation of spirometric parameters. Spirometric parameters of the case and control groups such as FVC, FEV1, FEV1/FVC and FEF25-75 were measured by Vitalograph spirometer (model: 2120 on ATS method, after the standard questionnaire of respiratory diseases had been completed during an interview and medical examination..Results: The mean of MMA concentration was 132.87 ± 220.67 ppm for STEL and 1.95 ± 3.59 ppm for TWA.The relationship between MMA concentration in the STEL and TWA exposures was significant (P<0.05 and the relationship between MMA concentration and ventilation was significant just for STEL. In this study no relationship between MMA concentration and spirometric parameters in both STEL and TWA exposures was found. Also there was no significant difference between spirometric parameters of the case group and normal values of the

[Study on the relationship between ER Rsa I gene polymorphism and children's dental fluorosis].

Science.gov (United States)

Ba, Yue; Li, Hai-Xia; Yin, Gong-Ju; Wu, Wei-Hua; Yu, Bo; Cheng, Xue-Min; Cui, Liu-Xin

2009-09-01

To explore the distribution of ER Rsa I genotype in children who lived in the areas with or without high fluoride, and evaluate the relationship between ER Rsa I gene polymorphism and children's dental fluorosis. Children aged 8 to 12 years, born and raised in high fluoride areas and control areas in two counties of Henan Province were recruited. The Rsa I marker of ER gene was genotyped in 237 children composed of both dental fluorosis cases and controls by PCR-RFLP procedure. Urine fluoride was detected with fluoride ion selective electrode method. The frequency distribution of ER Rsa I genotype was rr 60.81% (45/74), Rr 27.02% (20/74), RR 12.16% (9/74) in children with fluorosis; rr 73.91% (51/69), Rr 20.29% (14/69), RR 5.80% (4/69) in children without fluorosis from high fluoride areas, and rr 63.83% (60/94), Rr 34.04% (32/94), RR 2.13% (2/94) in the children without fluorosis from control areas respectively. There were no significant differences in the three groups (P>0.05), but children carrying allele R of ER Rsa I had a significantly increased risk of dental fluorosis (OR=1.821, 95% CI: 1.013-3.274) compared to children carrying the allele r in endemic fluorosis areas. Although no significant difference was found in ER Rsa I genotype between cases and non-dental fluorosis in endemic fluorosis areas, children carrying R allele of ER Rsa I had a higher risk compared to children carrying r allele, and the further study is needed.

Contrast-enhanced magnetic resonance angiography of persistent fifth aortic arch in children

International Nuclear Information System (INIS)

Zhong, Yumin; Zhu, Ming; Sun, Aimin; Li, Yuhua; Jaffe, Richard B.; Gao, Wei

2007-01-01

Cine angiography and echocardiography have been utilized to diagnose congenital aortic arch anomalies. However, the visualization of great vessels by echocardiography is limited, while cine angiography requires cardiac catheterization with ionizing radiation. Contrast-enhanced magnetic resonance angiography (MRA) is a noninvasive modality suitable for visualization of congenital aortic arch anomalies. To evaluate the utility of contrast-enhanced MRA in the diagnosis of persistent fifth aortic arch, a rare congenital aortic arch anomaly, and to compare the diagnostic accuracy of MRA with that of echocardiography and cine angiography. In four pediatric patients, contrast-enhanced MRA studies were performed for diagnosing persistent fifth aortic arch. The findings of MRA were compared with echocardiographic findings and confirmed by cine angiography and operation. Transthoracic surface echocardiography noted an aberrant vessel arising from the ascending aorta in two of four patients; the etiology of this vessel was uncertain. In the other two patients a diagnosis of coarctation was made. Of the four patients, only one was diagnosed with interruption of the aortic arch. Contrast-enhanced MRA clarified uncertain echocardiographic findings, enabling the correct diagnosis of persistent fifth aortic arch with fourth aortic arch interruption in all four patients. Contrast-enhanced MRA is a safe, accurate, and fast imaging technique for the evaluation of persistent fifth aortic arch and may obviate the need for conventional cine angiography. Cardiac catheterization may be reserved for some types of complicated congenital heart disease and for obtaining hemodynamic information. (orig.)

Dental pain and dental treatment of young children attending the general dental service.

Science.gov (United States)

Milsom, K M; Tickle, M; Blinkhorn, A S

2002-03-09

The objective was to examine the relationship between dental pain (and its sequelae), and the extent of restorative care provided for primary molars, amongst children who regularly attend a general dental practitioner. A retrospective review of the clinical case notes of 677 children with caries who attended 50 general dental practitioners on a regular basis. Analyses were performed at the subject level. Logistic regression models were fitted for the dependent variables whether or not pain, a dental extraction for pain or sepsis and a course of antibiotics was recorded, after taking into account the proportion of carious teeth that were restored, the total number of carious teeth, the age caries was first recorded, gender and the clustering of the subjects within dental practices. Almost half of the children in the study (48%) were recorded as having at least one episode of pain. Total decay experience in the primary molars was a significant predictor of pain, extraction due to pain or sepsis and prescription of antibiotics. There was no significant association between the proportion of carious teeth restored and each of the three dependent variables. For those children who regularly attend their general dental practitioner and who have decay in their primary molars, dental pain is a common finding. Total decay experience in primary molars is the principal predictor of pain, extraction due to pain and the need for antibiotics, whilst the level of restorative care in the primary dentition is less important. In order to reduce the incidence of dental pain in young children, effective methods of preventing caries at the individual and public health levels need to be expanded.

Is the South African exchange rate volatile? Application of the arch framework.

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Thato Julius Mokoma

2015-04-01

Full Text Available This study applies the autoregressive conditional heteroscedasticity (ARCH model to forecast exchange rate volatility in South Africa for the period 1990Q1 to 2014Q2. The ARCH (1 and ARCH (2 models were constructed using four variables; namely, exchange rate, gross domestic product, inflation and interest rates. Upon addressing the issue of stationarity, the models were fitted and the ARCH (1 model was found to be fit. This model revealed a high volatility of exchange rate compared to the ARCH (2 model. Prior to forecasting, the selected model was subjected to a battery of diagnostics tests and was found to be stable and well specified. The forecasts from the ARCH (1 model proved that in the near future, exchange rate will not be highly volatile though SA will experience depreciation in its currency.

Dental Workforce Availability and Dental Services Utilization in Appalachia: A Geospatial Analysis

Science.gov (United States)

Feng, Xue; Sambamoorthi, Usha; Wiener, R. Constance

2016-01-01

Objectives There is considerable variation in dental services utilization across Appalachian counties, and a plausible explanation is that individuals in some geographical areas do not utilize dental care due to dental workforce shortage. We conducted an ecological study on dental workforce availability and dental services utilization in Appalachia. Methods We derived county-level (n = 364) data on demographic, socio-economic characteristics and dental services utilization in Appalachia from the 2010 Behavioral Risk Factor Surveillance System (BRFSS) using person-level data. We obtained county-level dental workforce availability and physician-to-population ratio estimates from Area Health Resource File, and linked them to the county-level BRFSS data. The dependent variable was the proportion using dental services within the last year in each county (ranging from 16.6% to 91.0%). We described the association between dental workforce availability and dental services utilization using ordinary least squares regression and spatial regression techniques. Spatial analyses consisted of bivariate Local Indicators of Spatial Association (LISA) and geographically weighted regression (GWR). Results Bivariate LISA showed that counties in the central and southern Appalachian regions had significant (p dental workforce availability, low percent dental services utilization). GWR revealed considerable local variations in the association between dental utilization and dental workforce availability. In the multivariate GWR models, 8.5% (t-statistics >1.96) and 13.45% (t-statistics >1.96) of counties showed positive and statistically significant relationships between the dental services utilization and workforce availability of dentists and dental hygienists, respectively. Conclusions Dental workforce availability was associated with dental services utilization in the Appalachian region; however, this association was not statistically significant in all counties. The findings suggest

Prenuptial dental extractions in Acadian women: first report of a cultural tradition.

Science.gov (United States)

Gordon, Sara C; Kaste, Linda M; Barasch, Andrei; Safford, Monika M; Foong, W Choong; ElGeneidy, Adry

2011-12-01

Prenuptial tooth extractions, extractions of all teeth in at least one dental arch before marriage, are not identified in the dental literature. Driven by a professional encounter, the purpose of this study was to confirm the existence of this practice among Acadian women. An 8-item survey instrument with space for comments was mailed to 182 dentists from traditionally Acadian regions of Canada. The survey was provided in English and French. Ninety dentists responded (50.3%); 8 of them (9%) had been asked to perform prenuptial extractions, and an additional 9 volunteered awareness of this practice. Awareness and requests were associated with dental practice in a county with a ≥20% French-speaking population. Prenuptial extractions in this population have been confirmed by the current cohort of dentists. The potential public health, clinical, and systemic health research implications for women who are edentulous for most of their adult life merit further study. Additionally, it is important to determine if interventions are needed to curtail cultural expectations of such practices.

Structural properties and out-of-plane stability of roller bent steel arches

NARCIS (Netherlands)

Spoorenberg, R.C.

2011-01-01

In contemporary architecture the use of steel arches has seen a significant increase. They are applied in buildings and large span bridges, combining structural design with architectural merits. For arches lacking lateral support (or freestanding arches) the out-of-plane structural stability

Asymptotics of the QMLE for General ARCH(q) Models

DEFF Research Database (Denmark)

Kristensen, Dennis; Rahbek, Anders Christian

2009-01-01

-ARCH -- are derived. Strong consistency is established under the assumptions that the ARCH process is geometrically ergodic, the conditional variance function has a finite log-moment, and finite second moment of the rescaled error. Asymptotic normality of the estimator is established under the additional assumption...

Comparative analysis of the construction solution variants for flat arch coverings of buildings

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Ibragimov Aleksandr Mayorovich

2014-03-01

Full Text Available Arch structures of long span buildings’ coverings are more beneficial in respect to material expenses, than beam and frame systems. Constructive schemes of roof frameworks of arch coverings are diverse, which means their operation under loading differs much. The authors offer a number of construction solutions for flat arch coverings of long span buildings. The comparative analysis of these construction solutions is presented. The operation of radial link arch is observed. The arch consists of discontinuous top chord and radial bowstring under the single load (uniformly distributed and concentrated in nods with different spans and rises. The problem of radial link arch optimization is solved in dependence with arising forces and rise. The optimal camber of arch was found. In further works the authors plan to analyze spans more than 36 meters and solve the problem in case of asymmetrical loadings.

Jaw muscle pain and its effect on gothic arch tracings.

Science.gov (United States)

Obrez, A; Stohler, C S

1996-04-01

Perceived changes in occlusion and decreased range of motion are often expressed by patients with masticatory muscle pain. The adverse loading of craniomandibular tissues that results from an inadequate maxillomandibular relationship in combination with the coexisting dysfunction is widely regarded as the cause of pain. This study was designed to test whether pain can cause significant changes in position of the mandible and therefore form the basis for any perceived changes in the maxillomandibular relationship. A second objective was to determine whether pain can cause changes in the mandibular range of motion. Five subjects who rated pain intensity on a visual analog scale were used in a single-blind, randomized, repeated-measures study design. Tonic muscle pain was induced by infusion of 5% hypertonic saline solution into the central portion of the superficial masseter muscle. Isotonic saline solution was used as a control, with subjects blinded to the type of substance given. The effect of pain on the position of the apex of the gothic arch tracing, the direction of the lateral mandibular border movements, and the mandibular range of motion was studied in a horizontal plane with minimal occlusal separation. Pain significantly affected the position of the apex of the gothic arch tracing in anterior (F = 11.46, p = 0.03) and transverse (F = 35.0, p = 0.004) directions. Similarly, pain affected the orientation of the mandibular lateral border movements (F = 12.44, p = 0.02) and their magnitude (F = 14.97, p = 0.01). All pain-induced effects proved to be reversible. The observed effect of pain can explain the perceived change of bite that is frequently noted by patients with orofacial pain. This study provided evidence of an alternative causal relationship between pain and changes in occlusal relationship and questions occlusal therapy as treatment, directed toward the elimination of the underlying cause in patients with masticatory muscle pain.

Lateral testing of glued laminated timber tudor arch

Science.gov (United States)

Douglas R. Rammer; Philip Line

2016-01-01

Glued laminated timber Tudor arches have been in wide use in the United States since the 1930s, but detailed knowledge related to seismic design in modern U.S. building codes is lacking. FEMA P-695 (P-695) is a methodology to determine seismic performance factors for a seismic force resisting system. A limited P-695 study for glued laminated timber arch structures...

Twin - Arch technique. Revival of the "edgewise -Technique"?

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Jacob Karp

2012-01-01

The SNB – Bracket brings a new dimension into the orthodontic world which is most apparent in extraction cases. Its Teflon – like material has a very low friction coefficient thus, reducing the treatment time considerably. Through the use of low dimensioned arch wires, the Twin – Arch Technique becomes a Light – wire system and simultaneously provides good anchorage and torque control.

[Fabrication and accuracy research on 3D printing dental model based on cone beam computed tomography digital modeling].

Science.gov (United States)

Zhang, Hui-Rong; Yin, Le-Feng; Liu, Yan-Li; Yan, Li-Yi; Wang, Ning; Liu, Gang; An, Xiao-Li; Liu, Bin

2018-04-01

The aim of this study is to build a digital dental model with cone beam computed tomography (CBCT), to fabricate a virtual model via 3D printing, and to determine the accuracy of 3D printing dental model by comparing the result with a traditional dental cast. CBCT of orthodontic patients was obtained to build a digital dental model by using Mimics 10.01 and Geomagic studio software. The 3D virtual models were fabricated via fused deposition modeling technique (FDM). The 3D virtual models were compared with the traditional cast models by using a Vernier caliper. The measurements used for comparison included the width of each tooth, the length and width of the maxillary and mandibular arches, and the length of the posterior dental crest. 3D printing models had higher accuracy compared with the traditional cast models. The results of the paired t-test of all data showed that no statistically significant difference was observed between the two groups (P>0.05). Dental digital models built with CBCT realize the digital storage of patients' dental condition. The virtual dental model fabricated via 3D printing avoids traditional impression and simplifies the clinical examination process. The 3D printing dental models produced via FDM show a high degree of accuracy. Thus, these models are appropriate for clinical practice.

Dental Care Utilization for Examination and Regional Deprivation

Science.gov (United States)

Kim, Cheol-Sin; Han, Sun-Young; Lee, Seung Eun; Kang, Jeong-Hee; Kim, Chul-Woung

2015-01-01

Objectives: Receiving proper dental care plays a significant role in maintaining good oral health. We investigated the relationship between regional deprivation and dental care utilization. Methods: Multilevel logistic regression was used to identify the relationship between the regional deprivation level and dental care utilization purpose, adjusting for individual-level variables, in adults aged 19+ in the 2008 Korean Community Health Survey (n=220 258). Results: Among Korean adults, 12.8% used dental care to undergo examination and 21.0% visited a dentist for other reasons. In the final model, regional deprivation level was associated with significant variations in dental care utilization for examination (pdental care utilization for other reasons in the final model. Conclusions: This study’s findings suggest that policy interventions should be considered to reduce regional variations in rates of dental care utilization for examination. PMID:26265665

Discussion on construction project of lining arch reinforcing stone arch bridge%内衬拱加固石拱桥施工方案探讨

Institute of Scientific and Technical Information of China (English)

乔钧

2012-01-01

分析了石拱桥的常见病害及其原因，总结了石拱桥的加固技术，结合一个工程实例，对内衬拱加固石拱桥的有效施工方案进行了详细阐述，并证明了该加固方案的有效性。%This paper analysed the common diseases and its reasons of stone arch bridge, summed up the reinforcement technology of stone arch bridge, combining with an engineering example, elaborated in detail the effective construction scheme of lining arch reinforcing stone arch bridge, and proved the effectiveness of this reinforcement scheme.

Accuracy of a new elastomeric impression material for complete-arch dental implant impressions.

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Baig, Mirza R; Buzayan, Muaiyed M; Yunus, Norsiah

2018-05-01

The aim of the present study was to assess the accuracy of multi-unit dental implant casts obtained from two elastomeric impression materials, vinyl polyether silicone (VPES) and polyether (PE), and to test the effect of splinting of impression copings on the accuracy of implant casts. Forty direct impressions of a mandibular reference model fitted with six dental implants and multibase abutments were made using VPES and PE, and implant casts were poured (N = 20). The VPES and PE groups were split into four subgroups of five each, based on splinting type: (a) no splinting; (b) bite registration polyether; (c) bite registration addition silicone; and (d) autopolymerizing acrylic resin. The accuracy of implant-abutment replica positions was calculated on the experimental casts, in terms of interimplant distances in the x, y, and z-axes, using a coordinate measuring machine; values were compared with those measured on the reference model. Data were analyzed using non-parametrical Kruskal-Wallis and Mann-Whitney tests at α = .05. The differences between the two impression materials, VPES and PE, regardless of splinting type, were not statistically significant (P>.05). Non-splinting and splinting groups were also not significantly different for both PE and VPES (P>.05). The accuracy of VPES impression material seemed comparable with PE for multi-implant abutment-level impressions. Splinting had no effect on the accuracy of implant impressions. © 2018 John Wiley & Sons Australia, Ltd.

Optimal graft diameter and location reduce postoperative complications after total arch replacement with long elephant trunk for arch aneurysm.

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Kondoh, Haruhiko; Funatsu, Toshihiro; Toda, Koich; Kainuma, Satoshi; Kuki, Satoru; Taniguchi, Kazuhiro

2011-08-01

Total arch replacement with an elephant trunk is a standard treatment for arch aneurysm, but serious complications, such as paraplegia and peripheral embolization caused by flapping of the elephant trunk, remain. Moreover, dilation of the descending aorta and retrograde flow into the peri-graft space at the distal elephant trunk are frequent problems. We hypothesized that optimal graft diameter and location would reduce complications after total arch replacement with a long elephant trunk by achieving complete thrombosis and minimal dilation of the descending aorta around the elephant trunk. We treated 65 patients with arch aneurysm by total arch replacement with a long elephant trunk anastomosed at the base of the innominate artery. The graft diameter was undersized (10%-20% of the distal aorta's diameter). Elephant trunk length was determined by preoperative computed tomography to locate the distal end at Th6 to Th8. Thrombosis around the elephant trunk, diameter of the descending aorta, and distance between the descending aorta and the graft near the distal end of the elephant trunk were evaluated using computed tomography. The distal end of the elephant trunk was located at Th 8 ± 1. There were no operative deaths, 3 patients (5%) died in the hospital, and 3 patients (5%) experienced spinal cord injury, including 1 in whom permanent paraplegia developed. Computed tomography revealed complete thrombosis around the elephant trunk in 58 patients (89%). The descending aorta did not dilate further, and distance between the descending aorta and the graft progressively decreased. Optimal graft diameter and location minimized postoperative complications, with complete thrombosis and no dilation of the descending aorta around the long elephant trunk in most patients. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

NASA ARCH- A FILE ARCHIVAL SYSTEM FOR THE DEC VAX

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Scott, P. J.

1994-01-01

The function of the NASA ARCH system is to provide a permanent storage area for files that are infrequently accessed. The NASA ARCH routines were designed to provide a simple mechanism by which users can easily store and retrieve files. The user treats NASA ARCH as the interface to a black box where files are stored. There are only five NASA ARCH user commands, even though NASA ARCH employs standard VMS directives and the VAX BACKUP utility. Special care is taken to provide the security needed to insure file integrity over a period of years. The archived files may exist in any of three storage areas: a temporary buffer, the main buffer, and a magnetic tape library. When the main buffer fills up, it is transferred to permanent magnetic tape storage and deleted from disk. Files may be restored from any of the three storage areas. A single file, multiple files, or entire directories can be stored and retrieved. archived entities hold the same name, extension, version number, and VMS file protection scheme as they had in the user's account prior to archival. NASA ARCH is capable of handling up to 7 directory levels. Wildcards are supported. User commands include TEMPCOPY, DISKCOPY, DELETE, RESTORE, and DIRECTORY. The DIRECTORY command searches a directory of savesets covering all three archival areas, listing matches according to area, date, filename, or other criteria supplied by the user. The system manager commands include 1) ARCHIVE- to transfer the main buffer to duplicate magnetic tapes, 2) REPORTto determine when the main buffer is full enough to archive, 3) INCREMENT- to back up the partially filled main buffer, and 4) FULLBACKUP- to back up the entire main buffer. On-line help files are provided for all NASA ARCH commands. NASA ARCH is written in DEC VAX DCL for interactive execution and has been implemented on a DEC VAX computer operating under VMS 4.X. This program was developed in 1985.

A theoretical method for calculating the collapse load of steel circular arches

NARCIS (Netherlands)

Spoorenberg, R.C.; Snijder, H.H.; Hoenderkamp, J.C.D.

2012-01-01

Arches are frequently used in large span structures like bridges and roofs. Although these structural elements may be prone to various instability phenomena, stocky arches or slender arches with sufficient lateral bracing fail due to plastic collapse instead of in-plane buckling or out-of-plane

Relationship between dental caries and metabolic syndrome among 13 998 middle-aged urban Chinese.

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Cao, Xia; Wang, Dongliang; Zhou, Jiansong; Yuan, Hong; Chen, Zhiheng

2017-04-01

The association between dental caries and metabolic syndrome (MetS) is inconsistent. The aim of the present study was to assess the relationship between dental caries and MetS and its components in a middle-aged Chinese population. A cross-sectional analysis was performed of 13 998 participants aged 45-65 years undergoing a health check during 2013-14. An index variable of decayed, missing, and filled teeth (DMFT) was calculated. Logistic regression was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) after adjustment for sex, age, education level, dietary habits, alcohol use, smoking, physical activity, and periodontitis. Of the 13 998 participants, 6164 had dental caries and 7834 did not; 3571 had MetS, whereas 10 427 did not. Participants with severe caries showed a higher prevalence of MetS, abdominal obesity, elevated blood pressure, dyslipidemia, and hyperglycemia than those with mild or no caries (all P dental caries and those with two or more DMFT were 1.12 (95 % CI 1.14-1.74) and 1.09 (95 % CI, 0.89-1.21), respectively (P trend  caries were associated with MetS among subjects with hyperglycemia (OR 1.14 [95%CI, 0.98-1.34]; P caries and abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol, and elevated blood pressure (adjusted ORs [95 % CIs] 0.98 [0.82-1.16], 1.01 [0.85-1.19], 0.84 [0.70-1.00], and 0.96 [0.86-1.13], respectively; all P > 0.05). Dental caries were associated with MetS among middle-aged Chinese in the present study. © 2016 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Dental erosion caused by gastroesophageal reflux disease: a case report.

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Cengiz, Seda; Cengiz, M Inanç; Saraç, Y Sinasi

2009-07-22

Chronic regurgitation of gastric acids in patients with gastroesophageal reflux disease may cause dental erosion, which can lead in combination with attrition or bruxism to extensive loss of coronal tooth tissue. This clinical report describes treatment of severe tooth wear of a gastroesophageal reflux disease patient who is 54-year-old Turkish male patient. After his medical treatment, severe tooth wear, bruxism and decreased vertical dimensions were determined. The vertical dimension was re-established and maxillary and mandibular anterior and posterior teeth were prepared for metal-ceramic restorations. Metal-ceramic fixed partial dentures were fabricated as full mouth restorations for both maxillary and mandibular arches because of splinting all teeth. And then maxillary stabilization splint was fabricated for his bruxism history. Significant loss of coronal tooth structure must taken into consideration. Gastroesophageal reflux disease by itself or in combination with attrition, abrasion or bruxism may be responsible for the loss. An extensive diagnostic evaluation is essential for the medical and dental effects of the problem.

CREATIVITY METHODS IN TEACHING THE ARCH-DESIGN STUDIO

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EIGBEONAN Andrew B.

2013-07-01

Full Text Available The aim of this paper is to search and find methods of fostering creativity or ideas relating to creativity in teaching the arch-design studio. Teaching creativity through its methods will be making the students grounded in designing with creativity ideas and therefore we can have professionals that design and build with satisfaction, safety and complementary. It means we can have real buildings and places that satisfy our clients, the society and in harmony with the environment. Although there are similarities in the curricula of training architects all over the world, but educators go about it in their own convenient and suitable ways and styles. The ideas of creativity have been part of architecture from the onset, but are not deligently applied and also not formally incorporated in the curricula of training. The topic is also very relevant and timely as arch-educators and other stakeholders are of the opinion that something has to be done to improve the ways and methods of training architects, especially the teaching of the arch-design studio with regards to creativity. Through exploration of literature and interviews (physical and telephone call this paper finds methods of stimulating creativity ideas in the teaching of arch-design studio. Some of the methods of motivating creativity found in teaching the arch-design studio are: analogy, metaphors, biomimicry, brainstorming, attribute listing, mental map, TRIZ, restrictions, charrette, browsing, excursions, focus groups, other peoples viewpoints, using crazy ideas, using experts, visualizing a goal, working with dreams and images and giving students design tools such as drawings CAD and model making.

Burnout, depression and suicidal ideation in dental and dental hygiene students.

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Deeb, George R; Braun, Sarah; Carrico, Caroline; Kinser, Patricia; Laskin, Daniel; Golob Deeb, Janina

2018-02-01

The aim of this study was to assess the relationship between burnout, depressive symptoms and suicidal ideation in dental and dental hygiene students and to evaluate the influence of gender, programme type and year of study. Third- and fourth-year dental (DS) and first- and second-year hygiene students (DHS) completed the Patient Health Questionnaire (PHQ-9) and an abbreviated Maslach Burnout Inventory online as measures of depressive symptoms/suicidality and burnout, respectively. The statistical analyses included summary statistics and tests for intergroup comparisons (chi-square) to evaluate the influence of gender, programme type (DHS or DS) and year of study. Correlations between depression, suicidality and burnout were also conducted. A total of 32 dental hygiene and 119 dental students participated. 40% of the dental and 38% of the hygiene students met criteria for burnout. No differences were found between years or between programmes. Nine per cent of both dental and hygiene students were above the cut-off for moderate depressive symptoms, but there were no statistical differences between the third- and fourth-year dental and the first- and second-year hygiene students. Six per cent of the dental and 9% of the dental hygiene students were above the cut-off for clinically significant suicidal ideation, but there were no statistical differences between dental and hygiene students. There were no differences noted in the dental students based on gender for any of the measures. Depression was significantly associated with all three subscales of burnout. Suicidal ideation was only significantly related to the lack of personal accomplishment subscale of burnout. These findings suggest the need for introducing preventive measures for such affective states in dental and dental hygiene training programmes. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Strengthening Masonry Arches with Lime-Based Mortar Composite

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Valerio Alecci

2017-06-01

Full Text Available In recent decades, many strengthening interventions on masonry elements were performed by using fiber reinforced polymers (FRPs. These advanced materials proved to be effective to increase the load-carrying capacity of masonry elements and to improve their structural behavior, avoiding the most critical failure modes. Despite the advantages of this technique compared to more traditional methods, FRP systems have disadvantages related to their low resistance to high temperatures, impossibility of application on wet surfaces, low permeability, and poor compatibility with masonry supports. Therefore, composite materials made of a fiber textile embedded in an inorganic matrix were recently proposed as alternatives to FRPs for strengthening historic masonry constructions. These composite materials are easier to install, have higher resistance to high temperatures, and permit higher vapor permeability than FRPs. The inorganic matrix is frequently a cement-based mortar, and the composite materials made of a fiber textile embedded in a cement-based mortar are usually identified as FRCM (fabric reinforced cementitious matrix composites. More recently, the use of natural lime mortar as an inorganic matrix has been proposed as an alternative to cement-based mortars when historic compatibility with the substrate is strictly required, as in case of restoration of historic buildings. In this paper, the effectiveness of a fabric made of basalt fibers embedded in lime mortar matrix (Basalt-FRLM for the strengthening of masonry arches is investigated. An experimental investigation was performed on 1:2 scaled brick masonry arches strengthened at the extrados with a layer of Basalt-FRLM and tested under vertical load. The results obtained are compared with previous results obtained by the authors by testing masonry arches strengthened at their extrados with FRCM and FRP composites. This investigation highlights the effectiveness of Basalt-FRLM in increasing load

Reliability and Correlation of Static and Dynamic Foot Arch Measurement in a Healthy Pediatric Population.

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Scholz, Timo; Zech, Astrid; Wegscheider, Karl; Lezius, Susanne; Braumann, Klaus-Michael; Sehner, Susanne; Hollander, Karsten

2017-09-01

Measurement of the medial longitudinal foot arch in children is a controversial topic, as there are many different methods without a definite standard procedure. The purpose of this study was to 1) investigate intraday and interrater reliability regarding dynamic arch index and static arch height, 2) explore the correlation between both arch indices, and 3) examine the variation of the medial longitudinal arch at two different times of the day. Eighty-six children (mean ± SD age, 8.9 ± 1.9 years) participated in the study. Dynamic footprint data were captured with a pedobarographic platform. For static arch measurements, a specially constructed caliper was used to assess heel-to-toe length and dorsum height. A mixed model was established to determine reliability and variation. Reliability was found to be excellent for the static arch height index in sitting (intraday, 0.90; interrater, 0.80) and standing positions (0.88 and 0.85) and for the dynamic arch index (both 1.00). There was poor correlation between static and dynamic assessment of the medial longitudinal arch (standing dynamic arch index, r = -0.138; sitting dynamic arch index, r = -0.070). Static measurements were found to be significantly influenced by the time of day (P body mass index (P mind. For clinical purposes, static and dynamic arch data should be interpreted separately.

Accuracy and efficiency of full-arch digitalization and 3D printing: A comparison between desktop model scanners, an intraoral scanner, a CBCT model scan, and stereolithographic 3D printing.

Science.gov (United States)

Wesemann, Christian; Muallah, Jonas; Mah, James; Bumann, Axel

2017-01-01

The primary objective of this study was to compare the accuracy and time efficiency of an indirect and direct digitalization workflow with that of a three-dimensional (3D) printer in order to identify the most suitable method for orthodontic use. A master model was measured with a coordinate measuring instrument. The distances measured were the intercanine width, the intermolar width, and the dental arch length. Sixty-four scans were taken with each of the desktop scanners R900 and R700 (3Shape), the intraoral scanner TRIOS Color Pod (3Shape), and the Promax 3D Mid cone beam computed tomography (CBCT) unit (Planmeca). All scans were measured with measuring software. One scan was selected and printed 37 times on the D35 stereolithographic 3D printer (Innovation MediTech). The printed models were measured again using the coordinate measuring instrument. The most accurate results were obtained by the R900. The R700 and the TRIOS intraoral scanner showed comparable results. CBCT-3D-rendering with the Promax 3D Mid CBCT unit revealed significantly higher accuracy with regard to dental casts than dental impressions. 3D printing offered a significantly higher level of deviation than digitalization with desktop scanners or an intraoral scanner. The chairside time required for digital impressions was 27% longer than for conventional impressions. Conventional impressions, model casting, and optional digitization with desktop scanners remains the recommended workflow process. For orthodontic demands, intraoral scanners are a useful alternative for full-arch scans. For prosthodontic use, the scanning scope should be less than one quadrant and three additional teeth.

Complex branchial fistula: a variant arch anomaly.

Science.gov (United States)

De Caluwé, D; Hayes, R; McDermott, M; Corbally, M T

2001-07-01

A 5-year-old boy presented with an infected left-sided branchial fistula. Despite antibiotic treatment and repeated excision of the fistula, purulent discharge from the wound persisted. Three-dimensional computed tomography (3D CT) reconstruction greatly facilitated the diagnosis and management of this case by showing the course of the fistulous tract. The complexity of the tract suggests that this represents a variant arch anomaly because it contains features of first, second, third, and fourth arch remnants. Copyright 2001 by W.B. Saunders Company.

Children's experiences of dental anxiety.

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Morgan, Annie G; Rodd, Helen D; Porritt, Jenny M; Baker, Sarah R; Creswell, Cathy; Newton, Tim; Williams, Chris; Marshman, Zoe

2017-03-01

Dental anxiety is common among children. Although there is a wealth of research investigating childhood dental anxiety, little consideration has been given to the child's perspective. This qualitative study sought to explore with children their own experiences of dental anxiety using a cognitive behavioural therapy assessment model. Face-to-face, semi-structured interviews were conducted with dentally anxious children aged 11-16 years. The Five Areas model was used to inform the topic guide and analysis. Data were analysed using a framework approach. In total, 13 children were interviewed. Participants described their experiences of dental anxiety across multiple dimensions (situational factors and altered thoughts, feelings, physical symptoms, and behaviours). Participants placed considerable value on communication by dental professionals, with poor communication having a negative influence on dental anxiety and the dentist-patient relationship. This study confirms the Five Areas model as an applicable theoretical model for the assessment of childhood dental anxiety. Children provided insights about their own dental anxiety experiences that have not previously been described. © 2016 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

FEATURES OF DESIGN OF TIED-ARCH BRIDGES WITH FLEXIBLE INCLINED SUSPENSION HANGERS

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V. O. Samosvat

2017-10-01

Full Text Available Purpose. Investigation and analysis of the hanger arrangement and the structural stability of a Network arch bridge – a tied-arch bridge with inclined hangers that cross each other at least twice. It is also necessary to make a comparative analysis with other types of hanger arrangements. Methodology. The authors in their research investigated a large number of parameters to determine their influence in the force distribution in the arch. Eventually they determined optimal values for all parameters. These optimal values allowed developing a design guide that leads to optimal arch design. When solving this problem, the authors used three-dimensional finite element models and the objective was to determine the most suitable solution for a road bridge, with a span of 100 meters, consisting of two inclined steel arches, located on a road with two traffic lanes, subjected to medium traffic. The virtual prototype of the model is performed by finite element simulator Midas Civil. Findings. In this study, for the bridge deck, a concrete tie appears to be the best solution considering the structural behavior of network arches, but economic advantages caused by easier erection may lead to steel or a composite bridge deck as better alternatives. Design requirements and local conditions of each particular bridge project will decide the most economic deck design.Originality. To ensure passenger comfort and the stability and continuity of the track, deformations of bridges are constricted. A network arch is a stiff structure with small deflections and therefore suitable to comply with such demands even for high speed railway traffic.
A network arch bridge with a concrete tie usually saves more than half the steel required for tied arches with vertical hangers and concrete ties. Practical value. Following the study design advice given in this article leads to savings of about 60 % of structural steel compared with conventional tied arch bridges with

New Insight into the Toughening Mechanisms of Seashell: From Arch Shape to Multilayer Structure

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Quan Yuan

2016-01-01

Full Text Available A seashell is a closed three-dimensional curved surface formed by two symmetrical open shells. Three-point bending is performed on a pure aragonite straight beam (PASB model and a multilayer structure curved beam (MSCB model to elucidate the structure-property relationships of seashells. The integrity of the PASB is broken because of the introduction of a soft layer, but this drawback is compensated by the peculiar arch shape and the internal multilayer structure. The effective modulus, stiffness, and fracture energy of MSCB increase with an increase in volume fraction, aspect ratio of aragonite platelet, overlap ratio of hard layers, and ratio of the elastic modulus of the hard layer to the shear modulus of the soft layer. New design disciplines drawn from the MSCB model are peculiar arch shape, internal multilayer structure of larger volume fraction, and aspect ratio of hard layers and nanoscaled soft layers.

Preliminary Study of In Vivo Formed Dental Plaque Using Confocal Microscopy and Scanning Electron Microscopy

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KA. Al-Salihi

2009-12-01

Full Text Available Objective: Confocal laser scanning microscopy (CLSM is relatively a new light microscopical imaging technique with a wide range of applications in biological sciences. The primary value of CLSM for the biologist is its ability to provide optical sections from athree-dimensional specimen. The present study was designed to assess the thickness and content of in vivo accumulated dental plaque using CLSM and scanning electron microscopy (SEM.Materials and Methods: Acroflat lower arch splints (acrylic appliance were worn by five participants for three days without any disturbance. The formed plaques were assessed using CLSM combined with vital fluorescence technique and SEM.Results: In this study accumulated dental plaque revealed varied plaque microflora vitality and thickness according to participant’s oral hygiene. The thickness of plaque smears ranged from 40.32 to 140.72 μm and 65.00 to 128.88 μm for live (vital and dead accumulated microorganisms, respectively. Meanwhile, the thickness of plaque on the appliance ranged from 101 μm to 653 μm. CLSM revealed both dead and vital bacteria on the surface of the dental plaque. In addition, SEM revealed layers of various bacterial aggregations in all dental plaques.Conclusion: This study offers a potent non-invasive tool to evaluate and assess the dental plaque biofilm, which is a very important factor in the development of dental caries.

Relationship between Dental Anxiety and Health Locus of Control among Physiotherapy Students

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Pooja Agarwal

2013-01-01

Materials & Method: A total of 152 students participated in the study. Dental anxiety was assessed using the 5 item Modified Dental Anxiety Scale (MDAS and Locus of Control was assessed using the 18 item Multidimensional Health Locus of Control (MHLC scale. Results: A Statistically significant positive correlation was found between the internal dimension of MHLC and dental anxiety. Conclusions: HLC was found to play an important role in predicting the dental anxiety among physiotherapy students.

Tracheal Compression Caused by a Mediastinal Hematoma After Interrupted Aortic Arch Surgery.

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Hua, Qingwang; Lin, Zhiyong; Hu, Xingti; Zhao, Qifeng

2017-08-03

Congenital abnormalities of the aortic arch include interrupted aortic arch (IAA), coarctation of the aorta (CoA), and double aortic arch (DAA). Aortic arch repair is difficult and postoperative complications are common. However, postoperative tracheobronchial stenosis with respiratory insufficiency is an uncommon complication and is usually caused by increased aortic anastomotic tension. We report here a case of tracheal compression by a mediastinal hematoma following IAA surgery. The patient underwent a repeat operation to remove the hematoma and was successfully weaned off the ventilator.In cases of tracheobronchial stenosis after aortic arch surgery, airway compression by increased aortic anastomotic tension is usually the first diagnosis considered by clinicians. Other causes, such as mediastinal hematomas, are often ignored. However, the severity of symptoms with mediastinal hematomas makes this an important entity.

Histoire tertiaire de l'Arche de Brahmaputra ; son rôle dans la prospection des hydrocarbures du Haut Assam (Inde (résumé Tertiary History of Brahmaputra Arch. Its Role in Hydrocarbon Prospects of Upper Assam, India (Abstract

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Murty K. N.

2006-10-01

Full Text Available On analyse l'histoire tertiaire de la plate-forme du Haut Assam (Inde et on discute les facteurs géologiques responsables du caractère pétrolier de cette importante province ainsi que ses relations avec la ceinture mobile de Naga au Sud-Est et avec l'avant-fosse himalayenne au Nord-Ouest. A cette intention, on a préparé des cartes paléologiques pour différentes formations dans la vallée supérieure de l'Assam, basées sur de nombreux puits et levers géophysiques. A partir de ces cartes, on a construit une série de coupes paléogéologiques pour illustrer l'évolution structurale de la plate-forme du haut Assam. Cette étude montre que la structure régionale de la haute vallée de l'Assam est en subsurface une arche large - l'Arche de Brahrnaputra - parallèle à, et juste au sud de la rivière Brahmaputra, formée par un double basculernent opposé : un ancien talus vers le Sud-Est durant le Paléogène et l'autre tourné vers le Nord-Ouest pendant le Mio-Pliocène. On peut identifier deux phases de migration des hydrocarbures. L'étude permet l'affirmation d'objectifs futurs en Haut Assam. Cette arche a une histoire géologique voisine de celle de l'arche de Bend du centre-nord du Texas et de l'arche de Hunton-Seminole-Ozark en Oklahoma où de riches gisements ont été trouvés dans presque tous les terrains impliqués dans le bombement. The Tertiary history of Upper Assam shelf, India is analysed. The geological factors responsible for making this an important petroleum province and ifs relationship with the Nago mobile belt in the south-east and the Himalayan fore deep in the north-vvest ore discussed. Sub-crop maps of différent geological formations in Upper Assam Valley based on a number of drilled wells and various geophysical surveys ore prepared for this purpose. From these maps, a series of palaeogeological sections are constructed to illustrate the structural evolution of the Upper Assam shelf. The study reveals thot the

The relationship between childhood weight, dental caries and eating practices in children aged 4-8 years in Australia, 2004-2008.

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Hooley, M; Skouteris, H; Millar, L

2012-12-01

The association between overweight/obesity and dental caries in children is contentious with studies variously reporting positive or negative associations between the two conditions. Since 1995, Australia has experienced a rise in the prevalence of both conditions in its children. This study investigated the association between child weight, diet and dental problems in a nationally representative sample. Data from 4149 children (51.5% male) participating in the Longitudinal Study of Australian Children (LSAC) were used. The LSAC is a longitudinal study collecting data from a large representative cohort of Australian children; data from the first three waves were included with children aged 4-5 years, 6-7 years, and 8-9 years. Multivariate cross-sectional and prospective analyses were conducted to determine the relationships between child weight, diet and dental problems. Overweight/obesity was associated with sweet drink consumption and dental problems associated with consumption of fatty foods and sweet drinks. Underweight was associated with dental problems cross-sectionally, but both underweight and overweight at age 6-7 years predicted dental problems at age 8-9 years. Dental caries and body weight are influenced by diet. Overweight children may be consuming less fatty food but appear to be consuming more sweet drinks than normal-weight children, which can lead to both increased weight and dental caries. Dietary interventions designed to reduce the development of dental caries may also reduce the development and maintenance of overweight. © 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.

Personality and psychological factors: Effects on dental beliefs

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Siddhi Hathiwala

2015-01-01

Full Text Available Background: Dental treatment can be highly unpleasant for anxious patients. Despite all advancements, dental anxiety continues to upset the dentist-patient relationship. The psychological factors like individual personality and familial and peer influence may alter the dental beliefs of a patient. Aim: A cross-sectional questionnaire study was conducted among young adolescents to investigate the relationship among various psychological factors and the dental beliefs of an individual. Materials and Methods: A self-administered questionnaire was distributed among higher secondary school children, aged 15−17 years in Udupi district. The dental anxiety of the participants was measured using Modified Dental Beliefs scale and the personality traits were assessed using the Ten-Item Personality Inventory. Pearson′s correlation and chi-square analysis were performed among these scales. Independent t-test was performed to compare dental anxiety scores with different socio-demographic and psychological characteristics. Results: In all 198 students, with a mean age of 16.6 years, completed the questionnaire. A majority of the participants had lower MDBS scores. The personality traits like Emotional Stability and Openness to New Experiences showed a negative correlation with the Dental Belief scores. Apart from these, the experience at first dental visit and peer support also affected the dental beliefs of the adolescents. Conclusion: Various psychological traits of adolescents influence their dental anxiety.

Factors affecting use of word-of-mouth by dental patients.

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Jung, Yun-Sook; Yang, Hae-Young; Choi, Youn-Hee; Kim, Eun-Kyong; Jeong, Seong-Hwa; Cho, Min-Jeong; Nam, Soon-Hyeun; Song, Keun-Bae

2018-03-23

Word-of-mouth (WOM) refers to communication among consumers, which greatly influences the marketing strategies of dental clinics. This study aimed to explore factors that affect use of WOM by dental patients and to analyse their pathways. The participants were 520 outpatients from four private dental clinics. Data were obtained from a survey using self-reported questionnaires, which included questions regarding seven latent variables: five exogenous variables, including medical service quality (physical environment, customer service, patient relationship quality) and individual characteristic variables (opinion leader tendency, social hub tendency); and two endogenous variables (intention to recommend, WOM experience). Statistical analysis was performed using structural equation modelling. Significant associations were found in the pathways between relationship quality and intention to recommend, intention to recommend and WOM, and opinion leader tendency and WOM (P < 0.001). Higher patient relationship quality and higher intention to recommend were related to positive WOM, as was higher opinion leader tendency. Improving patient relationship quality can promote positive WOM for dental clinics. Strategies are needed to promote a positive perception of dental clinics by effectively responding to the views of patients with strong opinion leader tendencies. © 2018 FDI World Dental Federation.

Recurrent neck infection with branchial arch fistula in children.

Science.gov (United States)

Madana, J; Yolmo, Deeke; Kalaiarasi, R; Gopalakrishnan, S; Saxena, S K; Krishnapriya, S

2011-09-01

Acute suppurative neck infections associated with third or fourth branchial arch fistulas are frequently recurrent. Third and fourth branchial arch anomalies are much less common than those of second arch and usually present with left thyroid lobe inflammation. The authors present their experience with 15 cases of pyriform sinus fistulae (PSF) of third branchial arch origin and 3 cases of fourth arch origin, all of which presented as recurrent neck infection mainly on the left side. A retrospective review of 18 cases of third and fourth arch fistulae treated at JIPMER from 2005 to 2010. This study includes 18 patients with PSF diagnosed by the existence of fistulous tract radiologically and intraoperatively with pathological correlation. Neck exploration with excision of tract and left hemithyroidectomy was performed in all cases. The patients consisted of 7 males and 11 females, and the ages ranged from 3 to 15 years. All of them presented with recurrent episodes of neck infection. Investigations performed include computed tomography (CT) fistulography, barium swallow and ultrasound which were useful in delineating pyriform sinus fistulous tract preoperatively. All cases were on the left side and the fistula was identified by barium swallow in 14 cases (80%), while intraoperative and pathologic confirmation of the tract was possible in all cases (100%). Neck exploration with an emphasis on complete exposure of the recurrent laryngeal nerve and exposure of the pyriform sinus opening to facilitate complete fistulous tract excision with left hemithyroidectomy was successful in all patients. A follow up period of 1-3 years showed no recurrence. Recurrent neck infection in a child should alert the physician to the possibility of an underlying pyriform sinus fistula of branchial origin and CT fistulography should be performed after the resolution of the neck infection to delineate the tract anatomically. Crown Copyright © 2011. Published by Elsevier Ireland Ltd. All

Initial arch wires for tooth alignment during orthodontic treatment with fixed appliances.

Science.gov (United States)

Jian, Fan; Lai, Wenli; Furness, Susan; McIntyre, Grant T; Millett, Declan T; Hickman, Joy; Wang, Yan

2013-04-30

Initial arch wires are the first arch wires to be inserted into the fixed appliance at the beginning of orthodontic treatment and are used mainly for the alignment of teeth by correcting crowding and rotations. With a number of different types of orthodontic arch wires available for initial tooth alignment, it is important to understand which wire is most efficient, as well as which wires cause the least amount of root resorption and pain during the initial aligning stage of treatment. This is an update of the review 'Initial arch wires for alignment of crooked teeth with fixed orthodontic braces' first published in the Cochrane Database of Systematic Reviews 2010, Issue 4. To assess the effects of initial arch wires for alignment of teeth with fixed orthodontic braces in relation to alignment speed, root resorption and pain intensity. We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 2 August 2012), CENTRAL (The Cochrane Library 2012, Issue 7), MEDLINE via OVID (1950 to 2 August 2012) and EMBASE via OVID (1980 to 2 August 2012). We also searched the reference lists of relevant articles. There was no restriction with regard to publication status or language of publication. We contacted all authors of included studies to identify additional studies. We included randomised controlled trials (RCTs) of initial arch wires to align teeth with fixed orthodontic braces. Only studies involving participants with upper and/or lower full arch fixed orthodontic appliances were included. Two review authors were responsible for study selection, validity assessment and data extraction. All disagreements were resolved by discussion amongst the review team. Corresponding authors of included studies were contacted to obtain missing information. Nine RCTs with 571 participants were included in this review. All trials were at high risk of bias and a number of methodological limitations were identified. All trials had at least one

Evaluation of arch form between Vietnamese and North American Caucasians using 3-dimensional virtual models.

Science.gov (United States)

Trang, Vu Thi Thu; Park, Jae Hyun; Bayome, Mohamed; Shastry, Shruti; Mellion, Alex; Kook, Yoon-Ah

2015-01-01

The purpose of this study was to investigate the three-dimensional (3D) morphologic differences in the mandibular arch of Vietnamese and North American White subjects. The sample included 113 Vietnamese subjects (41 Class I, 37 Class II and 35 Class III) and 96 White subjects (29 Class I, 30 Class II and 37 Class III). The samples were regrouped according to arch form types (tapered, ovoid, and square) to compare the frequency distribution of the three arch forms between ethnic groups in each angle classification. The facial axis point of each tooth was digitized on 3D virtual models. Four linear and two ratio variables were measured. In comparing arch dimensions, the intercanine and intermolar widths were wider in Vietnamese than in Whites (p Vietnamese group, the square arch form was the most frequent followed by tapered and ovoid arch forms. The arch forms of Whites were narrower than Vietnamese. In North American Whites, the distribution of the arch form types showed similar frequency. In Vietnamese, the square arch form was more frequent.

Study on Dental Treatment with YAG Laser (1st Report): Temperature of Dental Tissue Irradiated with Laser Beam

OpenAIRE

上田, 隆司; 山田, 啓司; 古本, 達明

2000-01-01

The flash temperature of a dental hard tissue irradiated with pulsed Nd:YAG laser is measured using a two-color pyrometer with an optical fiber. This pyrometer consists of a chalcogenide optical fiber and a laminated infrared detector. The influence of the laser power on the temperature of the dental tissue is investigated, and the relationship between the laser power and the removal volume of the dental tissue is obtained. In order to examine the thermal damage on the dental tissue, hardness...

Optical silencing of C. elegans cells with arch proton pump.

Directory of Open Access Journals (Sweden)

Ayako Okazaki

Full Text Available BACKGROUND: Optogenetic techniques using light-driven ion channels or ion pumps for controlling excitable cells have greatly facilitated the investigation of nervous systems in vivo. A model organism, C. elegans, with its small transparent body and well-characterized neural circuits, is especially suitable for optogenetic analyses. METHODOLOGY/PRINCIPAL FINDINGS: We describe the application of archaerhodopsin-3 (Arch, a recently reported optical neuronal silencer, to C. elegans. Arch::GFP expressed either in all neurons or body wall muscles of the entire body by means of transgenes were localized, at least partially, to the cell membrane without adverse effects, and caused locomotory paralysis of worms when illuminated by green light (550 nm. Pan-neuronal expression of Arch endowed worms with quick and sustained responsiveness to such light. Worms reliably responded to repeated periods of illumination and non-illumination, and remained paralyzed under continuous illumination for 30 seconds. Worms expressing Arch in different subsets of motor neurons exhibited distinct defects in the locomotory behavior under green light: selective silencing of A-type motor neurons affected backward movement while silencing of B-type motor neurons affected forward movement more severely. Our experiments using a heat-shock-mediated induction system also indicate that Arch becomes fully functional only 12 hours after induction and remains functional for more than 24 hour. CONCLUSIONS/SGNIFICANCE: Arch can be used for silencing neurons and muscles, and may be a useful alternative to currently widely used halorhodopsin (NpHR in optogenetic studies of C. elegans.

Dental caries experience, rather than toothbrushing, influences the incidence of dental caries in young Japanese adults.

Science.gov (United States)

Sonoda, C; Ebisawa, M; Nakashima, H; Sakurai, Y

2017-06-01

A dose-response relationship between toothbrushing frequency and the incidence of dental caries has not been confirmed. Furthermore, no longitudinal study about this relationship has considered dental caries experience at baseline, which is an important factor influencing the frequency of future caries. To elucidate the association between the incidence of dental caries and toothbrushing frequency after adjusting for dental caries experience at baseline in a Japanese population. The 92 recruits of the Japan Maritime Self-Defense Force in Kure, Japan, in 2011 were followed up for 3 years. They underwent oral examination at the annual checkups and answered questions about toothbrushing frequency. The multiple logistic regression analysis was used to analyze the incidence of dental caries and to identify independent effects of toothbrushing frequency and dental caries experience at baseline. Furthermore, the relative importance of the incidence of dental caries was investigated among other independent variables using the partial adjusted R² score. Logistic regression analysis showed that toothbrushing frequency alone did not influence the increment in decayed, missing, and filled teeth (DMFT). However, DMFT at baseline alone was associated with the increment in DMFT (crude odds ratio, OR, 1.20, 95% confidence interval, CI, 1.08,1.33). In the fully adjusted model, only DMFT at baseline was associated with the increment in DMFT (adjusted OR 1.23, 95%CI 1.09,1.38). After three years, the incidence of dental caries in young adult Japanese males was influenced by DMFT at baseline, rather than toothbrushing frequency. Copyright© 2017 Dennis Barber Ltd.

Health promotion and dental caries.

Science.gov (United States)

Maltz, Marisa; Jardim, Juliana Jobim; Alves, Luana Severo

2010-01-01

The central idea of the Brazilian health system is to prevent the establishment of disease or detect it as early as possible. Prevention and treatment of dental caries are related to behavioral factors, including dietary and oral hygiene habits, which are related to many chronic diseases. Dental health promotion therefore should be fully integrated into broadly based health-promoting strategies and actions such as food and health policies, and general hygiene (including oral hygiene), among others. For decades, a linear relationship between sugar consumption and caries has been observed. Recent data has indicated that this relationship is not as strong as it used to be before the widespread use of fluoride. However, diet is still a key factor acting in the carious process. Oral hygiene is a major aspect when it comes to caries, since dental biofilm is its etiological factor. Oral hygiene procedures are effective in controlling dental caries, especially if plaque removal is performed adequately and associated with fluoride. An alternative to a more efficient biofilm control in occlusal areas is the use of dental sealants, which are only indicated for caries-active individuals. If a cavity is formed as a consequence of the metabolic activity of the biofilm, a restorative material or a sealant can be placed to block access of the biofilm to the oral environment in order to prevent caries progress. The prevention of dental caries based on common risk-factor strategies (diet and hygiene) should be supplemented by more disease-specific policies such as rational use of fluoride, and evidence-based dental health care.

Health promotion and dental caries

Directory of Open Access Journals (Sweden)

Marisa Maltz

2010-01-01

Full Text Available The central idea of the Brazilian health system is to prevent the establishment of disease or detect it as early as possible. Prevention and treatment of dental caries are related to behavioral factors, including dietary and oral hygiene habits, which are related to many chronic diseases. Dental health promotion therefore should be fully integrated into broadly based health-promoting strategies and actions such as food and health policies, and general hygiene (including oral hygiene, among others. For decades, a linear relationship between sugar consumption and caries has been observed. Recent data has indicated that this relationship is not as strong as it used to be before the widespread use of fluoride. However, diet is still a key factor acting in the carious process. Oral hygiene is a major aspect when it comes to caries, since dental biofilm is its etiological factor. Oral hygiene procedures are effective in controlling dental caries, especially if plaque removal is performed adequately and associated with fluoride. An alternative to a more efficient biofilm control in occlusal areas is the use of dental sealants, which are only indicated for caries-active individuals. If a cavity is formed as a consequence of the metabolic activity of the biofilm, a restorative material or a sealant can be placed to block access of the biofilm to the oral environment in order to prevent caries progress. The prevention of dental caries based on common risk-factor strategies (diet and hygiene should be supplemented by more disease-specific policies such as rational use of fluoride, and evidence-based dental health care.

Hybrid treatment of aortic arch disease

Science.gov (United States)

Metzger, Patrick Bastos; Rossi, Fabio Henrique; Moreira, Samuel Martins; Issa, Mario; Izukawa, Nilo Mitsuru; Dinkhuysen, Jarbas J.; Spina Neto, Domingos; Kambara, Antônio Massamitsu

2014-01-01

Introduction The management of thoracic aortic disease involving the ascending aorta, aortic arch and descending thoracic aorta are technically challenging and is an area in constant development and innovation. Objective To analyze early and midterm results of hybrid treatment of arch aortic disease. Methods Retrospective study of procedures performed from January 2010 to December 2012. The end points were the technical success, therapeutic success, morbidity and mortality, neurologic outcomes, the rate of endoleaks and reinterventions. Results A total of 95 patients treated for thoracic aortic diseases in this period, 18 underwent hybrid treatment and entered in this study. The average ages were 62.3 years. The male was present in 66.7%. The technical and therapeutic success was 94.5% e 83.3%. The perioperative mortality rate of 11.1%. There is any death during one-year follow- up. The reoperation rates were 16.6% due 2 cases of endoleak Ia and one case of endoleak II. There is any occlusion of anatomic or extra anatomic bypass during follow up. Conclusion In our study, the hybrid treatment of aortic arch disease proved to be a feasible alternative of conventional surgery. The therapeutic success rates and re- interventions obtained demonstrate the necessity of thorough clinical follow-up of these patients in a long time. PMID:25714205

Structural behaviour of masonry arch with no-horizontal springing settlement

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P. Zampieri

2018-01-01

Full Text Available This paper presents a calculation procedure for assessing the structural integrity of a masonry arch with non-horizontal springing settlement. By applying the Principle of Virtual Work (PVW to the deformed arch system, the procedure proposed herein details the reaction forces and thrust lines for each step of imposed settlement of the support. The procedure can also be used estimate the final displacement that causes complete failure of arch structural capacity. The results of the analysis procedure were compared against those obtained by experimental testing so as to validate the proposed calculation method

Technical improvement of arch setting machine for roadway drive. Kusshin kirihayo sewakuki no hensen

Energy Technology Data Exchange (ETDEWEB)

Fujino, T [Taiheiyo Coal Mining Co. Ltd., Tokyo (Japan)

1991-09-25

The following contents are described for a new type arch setting machine introduced to the Taiheiyo Coal Mining Co. (1) The excavation of drift in this coal mine is carried out by the excavating system combining the excavating machine (CM) and the transporter (SC) and the supporting method where arch type steel beams are used as the supporting material is used. (2) In order to automatize the arch setting work, this machine which combined the both functions of the arch lifter (developed in 1983) and the arch setting manipulator (ASM, developed in 1990). (3) This machine has the total weight of 1,500kg, is mounted on CM, and consists of the running part, the arm part, the boom part, and the end saucer part of steel arches. Further, simple fitting or removing can be made and the coal falling down is prevented by holding the coal wall during the arch setting work. (4) When this machine and the ASM were compared for the arch setting time in the working site, the former required about the half time period of the latter. 5 figs., 1 tab.

Ductal Stent Implantation in Tetralogy of Fallot with Aortic Arch Abnormality

Science.gov (United States)

Ergul, Yakup; Saygi, Murat; Ozyilmaz, Isa; Guzeltas, Alper; Odemis, Ender

2015-01-01

Stenting of patent ductus arteriosus is an alternative to palliative cardiac surgery in newborns with duct-dependent or decreased pulmonary circulation; however, the use of this technique in patients with an aortic arch abnormality presents a challenge. Tetralogy of Fallot is a congenital heart defect that is frequently associated with anomalies of the aortic arch and its branches. The association is even more common in patients with chromosome 22q11 deletion. We present the case of an 18-day-old male infant who had cyanosis and a heart murmur. After an initial echocardiographic evaluation, the patient was diagnosed with tetralogy of Fallot and right-sided aortic arch. The pulmonary annulus and the main pulmonary artery and its branches were slightly hypoplastic; the ductus arteriosus was small. Conventional and computed tomographic angiograms revealed a double aortic arch and an aberrant left subclavian artery. The right aortic arch branched into the subclavian arteries and continued into the descending aorta, whereas the left aortic arch branched into the common carotid arteries and ended with the patent ductus arteriosus. After evaluation of the ductal anatomy, we implanted a 3.5 × 15-mm coronary stent in the duct. Follow-up injections showed augmented pulmonary flow and an increase in oxygen saturation from 65% to 94%. The patient was also found to have chromosome 22q11 deletion. PMID:26175649

Full-scale load tests of Pearl-Chain arches

DEFF Research Database (Denmark)

Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

2017-01-01

-Decks: First an investigation of the system’s elastic response (maximum load of 648kN), and second a demonstration of its collapse mechanism and ultimate capacity (maximum load of 970kN). The full-scale test showed formation of plastic hinges and clear warning signs are observed at 84% of the failure load......A full-scale load test is made of two Pearl-Chain (PC) concrete arches in order to evaluate the structural response and assess the design safety. Pearl-Chain structures and Pearl-Chain arches are invented and patented at the Technical University of Denmark. PC-Arches consist of specially designed....... The ultimate, experimental load capacity is 14% higher than the calculated mainly due to the assumed static system used for the calculation. In addition to the full-scale test bridge the first ever permanent PC-Bridge is erected in Denmark in 2015....

In-Plane MEMS Shallow Arch Beam for Mechanical Memory

KAUST Repository

Hafiz, Md Abdullah Al; Kosuru, Lakshmoji; Ramini, Abdallah; Chappanda, Karumbaiah N.; Younis, Mohammad I.

2016-01-01

We demonstrate a memory device based on the nonlinear dynamics of an in-plane microelectromechanical systems (MEMS) clamped–clamped beam resonator, which is deliberately fabricated as a shallow arch. The arch beam is made of silicon, and is electrostatically actuated. The concept relies on the inherent quadratic nonlinearity originating from the arch curvature, which results in a softening behavior that creates hysteresis and co-existing states of motion. Since it is independent of the electrostatic force, this nonlinearity gives more flexibility in the operating conditions and allows for lower actuation voltages. Experimental results are generated through electrical characterization setup. Results are shown demonstrating the switching between the two vibrational states with the change of the direct current (DC) bias voltage, thereby proving the memory concept.

In-Plane MEMS Shallow Arch Beam for Mechanical Memory

KAUST Repository

Hafiz, Md Abdullah Al

2016-10-18

We demonstrate a memory device based on the nonlinear dynamics of an in-plane microelectromechanical systems (MEMS) clamped–clamped beam resonator, which is deliberately fabricated as a shallow arch. The arch beam is made of silicon, and is electrostatically actuated. The concept relies on the inherent quadratic nonlinearity originating from the arch curvature, which results in a softening behavior that creates hysteresis and co-existing states of motion. Since it is independent of the electrostatic force, this nonlinearity gives more flexibility in the operating conditions and allows for lower actuation voltages. Experimental results are generated through electrical characterization setup. Results are shown demonstrating the switching between the two vibrational states with the change of the direct current (DC) bias voltage, thereby proving the memory concept.

Regional cerebral perfusion for surgical correction of neonatal aortic arch obstruction.

Science.gov (United States)

Zhang, Hui; Cheng, Pei; Hou, Jia; Li, Lei; Liu, Hu; Liu, Ruifang; Ji, Bingyang; Luo, Yi

2009-05-01

One-stage repair of aortic arch obstruction and associated cardiac anomalies is a surgical challenge in infants.The purpose of the present study is to review the current outcome using regional cerebral perfusion (RCP) during a procedure correcting interrupted aortic arch (IAA) and also isolated aortic coarctation (CoA) and CoA combined with hypoplastic aortic arch (CoA-HyAA) in our center. Between January 2007 and July 2008, 24 infant patients with interrupted aortic arch (IAA) (n=3), isolated aortic coarctation (iCoA) (n=9) and aortic coarctation with hypoplastic aortic arch (CoA-HyAA) (n=12) underwent one-stage surgical correction in our hospital. End-to-end anastomosis was employed in 12 infants (IAA n=3 and iCoA n=9); for the other 12 patients with CoA-HyAA, an end-to-end extended anastomosis was used in 8 cases, end-to-side anastomosis in 2 cases, and composite heterologous pericardial patch in 2 cases. RCP with 40 mL/kg/min through the innominate artery during aortic arch reconstruction was employed for all pediatric patients. One single-dose histidine-ketoglutarate-tryptophan (HTK) solution was used for myocardial protection during CPB. Cardiopulmonary bypass time and aortic cross-clamp time were 165.6+/-32.4 min and 81.7+/-30.0 min, respectively. The mean regional cerebral perfusion time was 31.0+/-10.6 min; lowest nasopharyngeal temperature was 19.1+/-1.1 degrees C. Operative mortality rate in both groups was 8.3%. Mean follow-up was 10.5+/-4.8 months. There was no late mortality or postoperative neurologic, renal or hepatic complications. All patients are asymptomatic and are developing normally. One-stage total arch repair using the RCP technique is an excellent method that may minimize neurologic and renal complications. Our surgical strategy for arch anomaly has a low rate of residual and recurrent coarctation when performed in these infants.

Transverse effect of Haas and Hyrax appliances on the upper dental arch in patients with unilateral complete cleft lip and palate: A comparative study

Science.gov (United States)

Façanha, Anna Júlia de Oliveira; Lara, Tulio Silva; Garib, Daniela Gamba; da Silva Filho, Omar Gabriel

2014-01-01

Objective The aim of the present study was to evaluate the transverse effect of rapid maxillary expansion in patients with unilateral complete cleft lip and palate while comparing the Haas and Hyrax appliances. Methods The sample consisted of 48 patients divided into two groups: Group I - 25 patients treated with modified Haas appliance (mean age: 10 years 8 months); and Group II - 23 patients treated with Hyrax appliance (mean age: 10 years 6 months). Casts were taken during pre-expansion and after removal of the appliance at the end of the retention period. The models were scanned with the aid of the 3 Shape R700 3D scanner. Initial and final transverse distances were measured at cusp tips and cervical-palatal points of maxillary teeth by using the Ortho AnalyzerTM 3D software. Results The mean expansion obtained between cusp tips and cervical-palatal points for inter-canine width was 4.80 mm and 4.35 mm with the Haas appliance and 5.91 mm and 5.91 mm with the Hyrax appliance. As for first premolars or first deciduous molars, the values obtained were 6.46 mm and 5.90 mm in the Haas group and 7.11 mm and 6.65 mm in the Hyrax group. With regard to first molars, values were 6.11 mm and 5.24 mm in the Haas group and 7.55 mm and 6.31 mm in the Hyrax group. Conclusion Rapid maxillary expansion significantly increased the transverse dimensions of the upper dental arch in patients with cleft palate, with no significant differences between the Hass and Hyrax expanders. PMID:24945513

Transverse effect of Haas and Hyrax appliances on the upper dental arch in patients with unilateral complete cleft lip and palate: A comparative study

Directory of Open Access Journals (Sweden)

Anna Júlia de Oliveira Façanha

2014-04-01

Full Text Available Objective: The aim of the present study was to evaluate the transverse effect of rapid maxillary expansion in patients with unilateral complete cleft lip and palate while comparing the Haas and Hyrax appliances. Methods: The sample consisted of 48 patients divided into two groups: Group I - 25 patients treated with modified Haas appliance (mean age: 10 years 8 months; and Group II - 23 patients treated with Hyrax appliance (mean age: 10 years 6 months. Casts were taken during pre-expansion and after removal of the appliance at the end of the retention period. The models were scanned with the aid of the 3 Shape R700 3D scanner. Initial and final transverse distances were measured at cusp tips and cervical-palatal points of maxillary teeth by using the Ortho Analyzer(tm 3D software. Results: The mean expansion obtained between cusp tips and cervical-palatal points for inter-canine width was 4.80 mm and 4.35 mm with the Haas appliance and 5.91 mm and 5.91 mm with the Hyrax appliance. As for first premolars or first deciduous molars, the values obtained were 6.46 mm and 5.90 mm in the Haas group and 7.11 mm and 6.65 mm in the Hyrax group. With regard to first molars, values were 6.11 mm and 5.24 mm in the Haas group and 7.55 mm and 6.31 mm in the Hyrax group. Conclusion: Rapid maxillary expansion significantly increased the transverse dimensions of the upper dental arch in patients with cleft palate, with no significant differences between the Hass and Hyrax expanders.

A Preliminary Study of Staff Meetings as Viewed by Dental Hygienists

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Patrick Anderson

2011-12-01

Full Text Available Staff meetings in general dental practices represent what is be-lieved to be a key management strategy to build teams and to enhance efficiency and effec-tiveness. However, very little research has been done regarding staff meetings in dental offices. This study examined staff meetings from the viewpoint of dental hygienists who grow in unique careers in that they work largely independently of the dentist and yet typically within a dental practice while providing patient care and education. One-hundred-six dental hygienists completed a survey about staff meetings in dental offices. Key findings include: only approximately 43% of dental offices conduct morning huddles to get the day off to a smooth and organized start, 72% of dental practices conduct longer staff meetings with largely positive outcomes, including increasing practice efficiency and productivity, few practices (12% hold specific meetings only for the hygiene-department (and probably thereby miss some opportunities for practice im-provement, the most important variable by far to hygienists' job satisfaction is respect from the owner-dentist, and there exists an important and synergistic relationship among job sa-tisfaction, relationships with other staff and relationship with the owner-dentist.

Assessment of the influence of jogging on the shape of female foot arches.

Science.gov (United States)

Maslon, Agata; Golec, Joanna; Szczygiel, Elzbieta; Czechowska, Dorota; Golec, Boguslaw

2017-12-23

Both walking and its faster, running, consist of cyclical subsequent phases of swing and support; however, they differ in their time proportions as well as magnitude of acting forces. There is a lack of studies concerning the long-term consequences of repeated jogging cycles on the function of feet and, above all, on their permanent impact on the shape of foot arches. The objective of this study was to answer the question whether regular jogging changes the shape of the transverse and medial longitudinal arches of the feet. The research material consisted of 96 women with an average age of 26.57, and included 50 actively jogging women, and 46 of non-joggers. The study was performed with the use of EMED-SF force platform. The plantar surface of the foot was divided into 10 regions according to Cavanagh, for which peak pressure and contact time were established. Two indicators were defined: metatarsal bone pressure distribution pattern acc. to Kantali, and longitudinal arch index acc. to Cavanagh. The data obtained revealed more frequent occurrence of the greatest pressure under the centrally located metatarsal heads (lack of functional foot transverse arch) among the female joggers, compared with the non-joggers. Moreover, the findings indicate the higher frequency of medial longitudinal foot arch flattening among female runners, with a great deal of consistency between both feet, whereas results for the control group show asymmetrical medial arch shapes with right foot propensity to normal arch shape and left foot tendency for excessive arch. The observed differences in feet arch shapes between female joggers and non-joggers indicate the influence of jogging on feet functional adaptations.

Cervical vertebral and dental maturity in Turkish subjects.

Science.gov (United States)

Başaran, Güvenç; Ozer, Törün; Hamamci, Nihal

2007-04-01

The aim of this study was to investigate the relationships between the stages of calcification of teeth and the cervical vertebral maturity stages in Turkish subjects. A retrospective cross-sectional study was designed. The final study population consisted of 590 Turkish subjects. Statistical analysis of the data was performed with computer software. Spearman rank order correlation coefficients were used to assess the relationship between cervical vertebral and dental maturation. For a better understanding of the relationship between cervical vertebral maturation indexes and dental age, percentage distributions of the studied teeth were also calculated. Strict correlations were found between dental and cervical vertebral maturation of Turkish subjects. For males, the sequence from lowest to the highest was third molar, central incisor, canine, first premolar, second premolar, first molar, and second molar. For females, the sequence from lowest to the highest was third molar, canine, second premolar, first premolar, central incisor, first molar, and second molar. Dental maturation stages can be used as a reliable indicator of facial growth.

Highly tunable NEMS shallow arches

KAUST Repository

Kazmi, Syed N. R.; Hajjaj, Amal Z.; Da Costa, Pedro M. F. J.; Younis, Mohammad I.

2017-01-01

and surface nanomachining of a highly conductive device layer on a silicon-on-insulator wafer. By designing the structures to have gap to thickness ratio of more than four, the mid-plane stretching of the nano arches is maximized such that an increase

Electrostatically Tunable Nanomechanical Shallow Arches

KAUST Repository

Kazmi, Syed N. R.; Hajjaj, Amal Z.; Da Costa, Pedro M. F. J.; Younis, Mohammad I.

2017-01-01

-beam lithography and surface nanomachining of a highly conductive device layer on a silicon-on-insulator (SOI) wafer. The experimental results show good agreement with the analytical results with a maximum tunability of 108.14% for 180 nm thick arch with a

Selective cerebro-myocardial perfusion in complex congenital aortic arch pathology: a novel technique.

Science.gov (United States)

De Rita, Fabrizio; Lucchese, Gianluca; Barozzi, Luca; Menon, Tiziano; Faggian, Giuseppe; Mazzucco, Alessandro; Luciani, Giovanni Battista

2011-11-01

Simultaneous cerebro-myocardial perfusion has been described in neonatal and infant arch surgery, suggesting a reduction in cardiac morbidity. Here reported is a novel technique for selective cerebral perfusion combined with controlled and independent myocardial perfusion during surgery for complex or recurrent aortic arch lesions. From April 2008 to April 2011, 10 patients with arch pathology underwent surgery (two hypoplastic left heart syndrome [HLHS], four recurrent arch obstruction, two aortic arch hypoplasia + ventricular septal defect [VSD], one single ventricle + transposition of the great arteries + arch hypoplasia, one interrupted aortic arch type B + VSD). Median age was 63 days (6 days-36 years) and median weight 4.0 kg (1.6-52). Via midline sternotomy, an arterial cannula (6 or 8 Fr for infants) was directly inserted into the innominate artery or through a polytetrafluoroethylene (PTFE) graft (for neonates cerebro-myocardial perfusion was 39 ± 18 min (17-69). Weaning from cardiopulmonary bypass was achieved without inotropic support in three and with low dose in seven patients. One patient required veno-arterial extracorporeal membrane oxygenation. Four patients, body weight cerebro-myocardial perfusion is feasible in patients with complex or recurrent aortic arch disease, starting from premature newborn less than 2.0 kg of body weight to adults. The technique is as safe as previously reported methods of cerebro-myocardial perfusion and possibly more versatile. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Reduction of Zygomatic Arch Isolated Fracture Using Ultra Sound and Needle Marking.

Science.gov (United States)

Kim, Jun Sik; Park, Young Ji; Lee, Yoon Jung; Kim, Nam Gyun; Lee, Kyung Suk

2016-12-01

Zygomatic arch is a bony arch constituting the lateral midface, which consists of 25% of all midface fractures. There are a number of ways to evaluate the extent of zygomatic arch fracture. Some authors have reported successful treatment outcomes using ultrasound (U/S). To add to the previous methods, we have considered ways to accurately display the location of the fracture line while using U/S with 23 gauge needle marking. We introduce our method, which provided satisfactory results for reduction using a portable U/S, and it can evaluate the fracture line simultaneously when reduction of an isolated zygomatic arch fracture is necessary, and needle marking, which can easily point out the fracture line on U/S. We studied 21 patients with an isolated zygomatic arch fracture who underwent closed reduction using U/S and needle marking between 2013 and 2015. We achieved satisfactory results in all our cases with respect to reduction by using the Dingman elevator after performing a temporal approach incision, while confirming relative positioning between needle marking and zygomatic fracture at the same time, after insertion of a 23 gauge needle in the skin above the zygomatic arch fracture line parallel to it. We treated 21 patients with an isolated zygomatic arch fracture using U/S and the needle marking method, which provided satisfactory results because the extent of reduction of the fracture could be evaluated in real-time during the operation and exposure to radiation was reduced.

ARCH Models Efficiency Evaluation in Prediction and Poultry Price Process Formation

Directory of Open Access Journals (Sweden)

Behzad Fakari Sardehae

2016-09-01

Full Text Available Introduction: Poultry is an important commodity for household consumption. In recent years, price fluctuation for this commodity has caused an uncertain condition for consumers and poultry prices over the past two years has changed a lot. This has caused many changes and uncertainty in a purchase decision. Analysis of changes and volatility modeling can be a great help to predict the poultry prices and great facilities in creating appropriate policies in future. The prices of staples such as poultry consumption basket is highly variable because much of the protein is necessary for daily energy are supplied in this way to households. So when the price of chicken which has been changed over the past two years and has always been in the press and media attention, has been selected in this study. Fluctuations in price of chicken have caused a surge in consumer expectations and contributed in volatility of chicken price. Materials and Methods: In this study ARCH models have been used for daily price of poultry of Iran’s market and this was investigated for2012-13and2013-14.BecauseARCH models can model the impact of heterogeneous variance over time in time series data then the variance of time series, which is limited in time, has no time limit. Many time series are more complex than a linear patterns, thus, non-linear models are of particular importance in Economic Sciences and Econometrics. Accordingly, Engle presented that ARCH model can model the heterogeneous variance components of the error term. That is a disturbing element and modeling can help to examine and explore the relationship between the components can be found disturbing. Basically, these models fit the data to a cluster and periodic oscillations with high volatility and low volatility associated with the period. In this study, we used several different models like ARCH, GARCH, IGARCH, and TGARCH. The distribution of the error term of the model also followt-student distribution

Mediation and moderation effect of the big five personality traits on the relationship between self-perceived malocclusion and psychosocial impact of dental esthetics.

Science.gov (United States)

Spalj, Stjepan; Novsak, Alenka; Bilobrk, Philipp; Katic, Visnja; Zrinski, Magda Trinajstic; Pavlic, Andrej

2016-05-01

To explore the mediation and moderation effects of personality traits on the relationship between self-perceived malocclusion and the psychosocial impact of dental esthetics. The sample included 252 subjects (62% female) aged 12-39 years. Self-perceived malocclusion was estimated using the 10-point scale Aesthetic Component of the Index of Orthodontic Treatment Need. The Psychosocial Impact of Dental Aesthetics Questionnaire was used to assess the psychological impact and the Big Five Inventory for personality traits. Moderation and mediation effects were evaluated with Pearson correlations and stepwise regression analysis, respectively. Self-perceived malocclusion ranged from 1 to 8 and was the most significant predictor of psychosocial impact of dental esthetics, whose unique contribution accounted for 11%-36.4% of variability, while age and sex accounted for 1.2%-2.5%. Personality traits had no mediating effect on this relationship. The moderating effect of agreeableness was present in the relationship between self-perceived degree of malocclusion and Social Impact (SI), Psychological Impact (PI), and Aesthetic Concern (AC) (ΔR2  =  0.035, 0.020, and 0.013, respectively; P personality traits. Adolescents and young adults with lower agreeableness and conscientiousness seem to be less affected by the increased severity of self-perceived malocclusion, as demonstrated in reporting some psychosocial impacts.

Effects of pelvic rotation and needle angle on pubic arch interference during transperineal prostate implants

International Nuclear Information System (INIS)

Tincher, Sandra A.; Kim, Robert Y.; Ezekiel, Mark P.; Zinsli, Tom; Fiveash, John B.; Raben, David A.; Bueschen, Anton J.; Urban, Donald A.

2000-01-01

Purpose: Pubic arch interference due to an enlarged prostate gland or a narrow pubic arch is often a limiting factor in adequate prostate coverage during transperineal brachytherapy. The purpose of this study was to evaluate the effects of both pelvic rotation and needle angles on pubic arch interference using CT-based 3-D information. Methods and Materials: Seven patients had CT imaging in both supine and lithotomy positions and 3-D treatment planning was performed with three needle angles (20 downward, 0, 20 upward). The pubic arch interference was then measured and comparisons were made for each needle trajectory and pelvic position. Results: Increasing pelvic rotation from supine to lithotomy position shows less pubic arch interference. Directing the needle tip upward shows less pubic arch interference in both supine and lithotomy positions when compared to needle tips directed downward. Conclusions: Both pelvic position and needle angles are important factors influencing pubic arch interference. Preplanning CT-based 3-D information may assist for individualized treatment planning in patients with a significant bony interference, thus avoiding pubic arch interference during implantation

The relationship between the flexible flatfoot and plantar fasciitis: ultrasonographic evaluation.

Science.gov (United States)

Huang, Yu-Chi; Wang, Lin-Yi; Wang, Her-Cherng; Chang, Kai-Lan; Leong, Chau-Peng

2004-06-01

The purpose of this study was to investigate the relationship between flexible flatfoot and plantar fasciitis. Twenty-three subjects with flexible flatfoot and 23 subjects with normal arched feet were enrolled. Footprint analysis was used to evaluate the foot conditions in both groups to calculate the individual arch index. We compared the sonographic images of plantar fascia in the flexible flatfoot group with the normal arch group using high-frequency ultrasound. The analysis results indicated that the thickening of the plantar fascia in the flexible flatfoot group was significantly different from the normal arch group. In the flexible flatfoot group, 10 of 23 patients (43.4%) had plantar fasciitis, but only two subjects (8.7%) in the normal arch group had plantar fasciitis. There was a higher incidence of plantar fasciitis in the flexible flatfoot group than the normal arch control group in this study.

Dental x-ray validation study: comparison of information from patient interviews and dental charts

International Nuclear Information System (INIS)

Preston-Martin, S.; Bernstein, L.; Maldonado, A.A.; Henderson, B.E.; White, S.C.

1985-01-01

Information was collected from dentists of a subset of participants in a case-control interview study conducted in Los Angeles County, California, in August 1980-August 1981 to evaluate the relationship of dental x-rays to tumors of the parotid gland. Complete dental charts were available from 142 dentists of 84 cases and from 130 dentists of 79 control. Analysis of data from these interview chart comparisons indicates that recall appears to be unbiased since the measures of agreement between interview and dental chart data are similar for cases and controls. The authors further conclude that interview data alone may be used for case-control comparisons of dental x-ray exposure and would, because of unbiased misclassification, tend to underestimate the relative risks. 12 references, 3 tables

The application of data measurement before the pedicle vertebral arch fixed operation with spiral CT

International Nuclear Information System (INIS)

Yang Zenian; Luo Zhongyao; Chen Yong'an

2003-01-01

Objective: Authors carry out volume scans and 3D surface reconstruction. Then authors get the precise data of pedicle of vertebral arch, entering nail angle on horizontal direction, entering nail screw length, and the smallest horizontal diameter and entering nails' distance on pedicle of vertebral arch before the pedicle vertebral arch fixed operation. Method: Select the axial image of the widest pedicle of vertebral arch and it SSD image, measure the entering nail distance on the pedicle of vertebral arch, TSA, entering nail screw length, and the smallest horizontal diameter of the pedicle of vertebral arch. Result: The method helps to prepare the length, size and location of the nail and TSA for the pedicle of vertebral arch fixed operation, increase the operation success rate. Conclusion: This is a simple and reliable method to prepare the precise data of the nail length and size, TSA for the operation

Multi-detector row computed tomographic evaluation of a rare type of complete vascular ring: Double aortic arch with atretic left arch distal to the origin of left subclavian artery

Energy Technology Data Exchange (ETDEWEB)

Hung, Ying Ying; Fu, Ching Yun; Wei, Hao Ji; Tsai, I Chen; Chen, Clayton Chi Chang [Taichung Veterans General Hospital, Taichung (China)

2013-10-15

Double aortic arch with an atretic left arch distal to the origin of left subclavian artery was diagnosed with multi-detector row computed tomography (MDCT) in two children with dysphagia. This rare type of complete vascular ring is clinically important because it may be confused with right aortic arch in mirror imaging. Anatomic details of this rare type of complete vascular ring demonstrated on MDCT facilitated appropriate surgical treatment.

The distribution of cervical vertebrae anomalies among dental malocclusions

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Hasan Kamak

2015-01-01

Full Text Available Aims: The aims of our study were to investigate the distribution of cervical vertebrae anomalies (CVAs among dental Angle Class I, II, and III malocclusions in Turkish population and whether a correlation between CVA and dental malocclusion. Materials and Methods: The study was performed on lateral cephalometric radiographs which were taken at the Department of Orthodontics, Faculty of Dentistry, Kirikkale University. The final sample of 318 orthodontic patients was included in the study. Dental malocclusions were performed according to Angle classification. CVAs were categorized: (1 fusion and (2 posterior arch deficiency (PAD. The Chi-square test was used to the analysis of the potential differences among dental malocclusions. Results: The final sample of 318 patients was examined. CVA was observed in 42 individuals (of 26 [8.17%] had fusion and 16 [5.03%] had PAD, with a frequency of 13.2%. Of the 26 fusion defect, 8 (30.7% had Angle Class I, 8 (30.7% had Angle Class II, and 10 (38.4% had Angle Class III malocclusion. Of the 16 PAD, 8 (50% had Angle Class I, 8 (50% had Angle Class II but no patients with Angle Class III malocclusion was observed. The distribution of dental malocclusions regarding CVA was not statistically significant (P = 0.076. Of these 42 individuals with CVA, 52.3% (15 fusions and 7 PAD were females and 47.7% (11 fusions and 9 PAD were males. Conclusion: In our study, the prevalence of fusion and PAD were found 8.1% and 5.0% in Turkish population, respectively. Besides, no statistically significant correlation between CVA and Angle Class I, II, and III malocclusions were found. Our findings support the studies showing no gender dimorphism.

Occlusion and Temporomandibular Function among Subjects with Mandibular Distal Extension Removable Partial Dentures.

NARCIS (Netherlands)

Creugers, N.H.J.; Witter, D.J.; Spijker, A. van 't; Gerritsen, A.E.; Kreulen, C.M.

2010-01-01

Objective. To quantify effects on occlusion and temporomandibular function of mandibular distal extension removable partial dentures in shortened dental arches. Methods. Subjects wearing mandibular extension removable partial dentures (n = 25) were compared with subjects with shortened dental arches

The surgical importance of an axillary arch in sentinel node biopsy.

LENUS (Irish Health Repository)

Ridgway, P F

2011-03-01

When Carl Langer described the aberrant axillary arch in 1846 its relevance in sentinel node biopsy (SNB) surgery could not have been contemplated. The authors define an incidence and elucidate relevance of the arch in SNB of the axilla.

Abnormal innominate vein and right aortic arch, an uncommon association that should be taken into account

International Nuclear Information System (INIS)

Catala, J.; Martin, C.

2000-01-01

A case of abnormal innominate vein associated with right aortic arch and aberrant left subclavian artery is presented. It was an incidental finding during the radiological study of an 8-year old boy suspected of having tuberculosis. The authors review the different etiological theories, radiological features and diagnostic impact of this uncommon venous malformation, as well as its relationship to other cardiovascular anomalies. (Author) 9 refs

The relationship between dental status, food selection, nutrient intake, nutritional status, and body mass index in older people

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Wagner Marcenes

2003-05-01

Full Text Available This paper reviewed the findings from a national survey in Great Britain which assessed whether dental status affected older people's food selection, nutrient intake, and nutritional status. The survey analyzed national random samples of free-living and institution subjects for dental examination, interview, and four-day food diary as well as blood and urine tests In the free-living sample, intakes of non-starch polysaccharides, protein, calcium, non-heme iron, niacin, and vitamin C were significantly lower in edentulous as compared to dentate subjects. People with 21 or more teeth consumed more of most nutrients, particularly non-starch polysaccharides. This relationship in intake was not apparent in the hematological analysis. Plasma ascorbate and retinol were the only analytes significantly associated with dental status. Having 21 or more teeth increased the likelihood of having an acceptable body mass index (BMI. Thus, maintaining a natural and functional dentition defined as having more than twenty teeth into old age plays an important role in having a healthy diet rich in fruits and vegetables, a satisfactory nutritional status, and an acceptable BMI.

Metallic artifacts caused by dental metal prostheses on PET images. A PET/CT phantom study using different PET/CT scanners

International Nuclear Information System (INIS)

Shimamoto, Hiroaki; Kakimoto, Naoya; Murakami, Shumei; Furukawa, Souhei; Fujino, Kouichi; Hamada, Seiki; Shimosegawa, Eku; Hatazawa, Jun

2009-01-01

The objective of this study was to investigate the effects of computed tomography (CT) artifacts caused by dental metal prostheses on positron emission tomography (PET) images. A dental arch cast was fixed in a cylindrical water-bath phantom. A spherical phantom positioned in the vicinity of the dental arch cast was used to simulate a tumor. To simulate the tumor imaging, the ratio of the 18 F-fluoro-deoxy-glucose radioactivity concentration of the spherical phantom to that of the water-bath phantom was set at 2.5. A dental bridge composed of a gold-silver-palladium alloy on the right mandibular side was prepared. A spherical phantom was set in the white artifact area on the CT images (site A), in a slightly remote area from the white artifact (site B), and in a black artifact area (site C). A PET/CT scan was performed with and without the metal bridge at each simulated tumor site, and the artifactual influence was evaluated on the axial attenuation-corrected (AC) PET images, in which the simulated tumor produced the strongest accumulation. Measurements were performed using three types of PET/CT scanners (scanners 1 and 2 with CT-based attenuation correction, and 3 with Cesium-137 ( 137 Cs)-based attenuation correction). The influence of the metal bridge was evaluated using the change rate of the SUVmean with and without the metal bridge. At site A, an overestimation was shown (scanner 1: +5.0% and scanner 2: +2.5%), while scanner 3 showed an underestimation of -31.8%. At site B, an overestimation was shown (scanner 1: +2.1% and scanner 2: +2.0%), while scanner 3 showed an underestimation of -2.6%. However, at site C, an underestimation was shown (scanner 1: -25.0%, scanner 2: -32.4%, and scanner 3: -8.4%). When CT is used for attenuation correction in patients with dental metal prostheses, an underestimation of radioactivity of accumulated tracer is anticipated in the dark streak artifact area on the CT images. In this study, the dark streak artifacts of the CT

Parascapular mass revealing primary tuberculosis of the posterior arch

Science.gov (United States)

Arbault, Anais; Ornetti, Paul; Chevallier, Olivier; Avril, Julien; Pottecher, Pierre

2016-01-01

We report the case of a parascapular abscess revealing primary tuberculosis of the posterior arch in a 31-year-old man. Sectional imaging is essential in order to detect the different lesions of this atypical spinal tuberculosis as osteolysis of the posterior arch extendible to vertebral body, osteocondensation, epidural extension which is common in this location, and high specificity of a zygapophysial, costo-vertebral or transverse arthritis. PMID:27709081

Contemporary results of surgical repair of recurrent aortic arch obstruction.

Science.gov (United States)

Mery, Carlos M; Khan, Muhammad S; Guzmán-Pruneda, Francisco A; Verm, Raymond; Umakanthan, Ramanan; Watrin, Carmen H; Adachi, Iki; Heinle, Jeffrey S; McKenzie, E Dean; Fraser, Charles D

2014-07-01

There is a paucity of data on the current outcomes of surgical intervention for recurrent aortic arch obstruction (RAAO) after initial aortic arch repair in children. The goal of this study is to report the long-term results in these patients. All patients undergoing surgical intervention for RAAO at Texas Children's Hospital from 1995 to 2012 were included. The cohort was divided into four groups based on initial procedure: (1) simple coarctation repair, (2) Norwood procedure, (3) complex congenital heart disease, and (4) interrupted aortic arch. A total of 48 patients age 9 months (range, 22 days to 36 years) underwent 49 procedures for RAAO. All patients had an anatomic repair consisting of either patch aortoplasty (n=27, 55%), aortic arch advancement (n=8, 16%), sliding arch aortoplasty (n=6, 12%), placement of an interposition graft (n=2, 17%), reconstruction with donor allograft (n=4, 8%), extended end-to-end anastomosis (n=1, 2%), or redo Norwood-type reconstruction (n=1, 2%). Most procedures (n=46, 94%) were performed through a median sternotomy using cardiopulmonary bypass. At a median follow-up of 6.1 years (range, 9 days to 17 years), only 2 patients required surgical or catheter-based intervention for RAAO. Hypertension was present in 10% of patients at last follow-up. There were no neurologic or renal complications. There was 1 perioperative death after an aortic arch advancement in group 1. Four other patients have died during follow-up, none of the deaths related to RAAO. Anatomic repair of RAAO is a safe procedure associated with low morbidity and mortality, and low long-term reintervention rates. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Acute Aortic Arch Perforation During Transcatheter Aortic Valve Replacement in Bicuspid Aortic Stenosis and a Gothic Aortic Arch.

Science.gov (United States)

Millan-Iturbe, Oscar; Sawaya, Fadi J; Bieliauskas, Gintautas; Chow, Danny H F; De Backer, Ole; Søndergaard, Lars

2017-09-01

Transcatheter aortic valve replacement (TAVR) has evolved from a novel technology to an established therapy for high/intermediate-risk patients with severe symptomatic aortic stenosis (AS). Although TAVR is used to treat bicuspid severe AS, the large randomized trials typically excluded bicuspid AS because of its unique anatomic features. This case report describes an acute aortic perforation during delivery of a transcatheter heart valve to treat a severe bicuspid AS with a "gothic aortic arch"; more careful evaluation of the preprocedural multislice computed tomographic scan would have unveiled a sharply angulated aortic arch. This life-threatening complication was successfully treated by thoracic endovascular aortic repair. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Dental esthetics--instrument for recreating a new facial esthetic to the elderly patient.

Science.gov (United States)

Scutariu, Mihaela Monica; Forna, Norina

2014-01-01

The major objective of this paper consists in underlining the wide range of possibilities in assessing the elderly patient; it relies on clinical examination in order to exclusively improve the patient's physiognomic aspect. In this context it has been organized a study which included 64 elderly patients aged between 60 and 90 years of age (median age 75), which presented themselves at the Clinical Service of Dental Semiology and Gerontostomatology between 2011-2012; they requested the restoration of the functions affected by odontal coronary lesions, periodontal disorders or edentations more or less expanded, malocclusions, malrelations of the mandible to the skull and unsuccessful or deteriorated dental or prosthetic treatments. The restoration of dental arches has been performed relying on common sense and power of discernment, respecting both facial features and expression by redimensioning the lower part of the face, repositioning the mandible and using gnatoprosthetic devices. Solving the problems elderly patients confront themselves with and the success of the treatment has been possible only after a correct assessment of the involutive phenomena that influence the oral cavity, after understanding the local and general factors that predispose to oral disorders as well as the differences between various techniques and materials.

The Response of Clamped Shallow Sandwich Arches with Metallic Foam Cores to Projectile Impact Loading

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Yanping Fan

Full Text Available Abstract The dynamic response and energy absorption capabilities of clamped shallow sandwich arches with aluminum foam core were numerically investigated by impacting the arches at mid-span with metallic foam projectiles. The typical deformation modes, deflection response, and core compression of sandwich arches obtained from the tests were used to validate the computation model. The resistance to impact loading was quantified by the permanent transverse deflection at mid-span of the arches as a function of projectile momentum. The sandwich arches have a higher shock resistance than the monolithic arches of equal mass, and shock resistance could be significantly enhanced by optimizing geometrical configurations. Meanwhile, decreasing the face-sheet thickness and curvature radius could enhance the energy absorption capability of the sandwich arches. Finite element calculations indicated that the ratio of loading time to structural response time ranged from 0.1 to 0.4. The projectile momentum, which was solely used to quantify the structural response of sandwich arches, was insufficient. These findings could provide guidance in conducting further theoretical studies and producing the optimal design of metallic sandwich structures subjected to impact loading.

Is obesity associated to dental caries in Brazilian schoolchildren?

Science.gov (United States)

Fernández, María Raquel; Goettems, Marília Leão; Demarco, Flávio Fernando; Corrêa, Marcos Britto

2017-11-06

This cross-sectional study aimed to determine the association between dental caries and weight status, and between dental caries and physical activity in Brazilian schoolchildren aged 8 to 12 years. A multi-stage sample of children enrolled in 20 private and public schools in 2010 in Pelotas, Southern Brazil, were invited to participate in the study. Socioeconomic data were collected from parents, and data regarding children characteristics were collected from children using a questionnaire and anthropometric measures. The Body Mass Index was obtained, and children were classified as overweight/obese considering age and sex. Dental examinations were performed to assess the presence of gingival inflammation, dental caries prevalence (DMFT≥1) and dental caries experience (mean DMFT). Multivariate Poisson Regression was used to assess factors associated with dental caries prevalence and experience. A total of 1,210 children were included in the study. Dental caries prevalence was 32.4% (95% CI 29.7-35.2), while the mean DMFT was 0.64 (± SD 1.00). Children who practiced less than 300 minutes per week of physical activity and overweigh/obese children had lower prevalence of dental caries, while children with obesity or overweight presented lower dental caries experience. Obesity/overweight and physical activity level presented an inverse relationship with dental caries. Longitudinal studies investigating the complexity of this relationship are required.

Initial arch wires for alignment of crooked teeth with fixed orthodontic braces.

LENUS (Irish Health Repository)

Wang, Yan

2010-01-01

The initial arch wire is the first arch wire to be inserted into the fixed appliance at the beginning of orthodontic treatment and is used mainly for correcting crowding and rotations of teeth. With a number of orthodontic arch wires available for initial tooth alignment, it is important to understand which wire is most efficient, as well as which wires cause the least amount of root resorption and pain during the initial aligning stage of treatment.

Relation of Gothic arch apex to dentist-assisted centric relation.

Science.gov (United States)

Myers, M; Dziejma, R; Goldberg, J; Ross, R; Sharry, J

1980-07-01

These data suggest that the widely held belief that thumb pressure can position the mandible consistently more posterior than the position indicated by the Gothic arch apex is unfounded. Furthermore, this study provides no evidence to support the contention that the dentist-assisted jaw relation is more reproducible than the relation indicated by the Gothic arch apex.

The relationship between panoramic indices and dental implant failure

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Cho, Hyun Jung; Yi, Won Jin; Heo, Min Suk; Lee, Jin Koo; Lee, Sam Sun; Choi, Soon Chul [Seoul National University College of Medicine, Seoul (Korea, Republic of); An, Chang Hyeon [Kyungpook National University College of Medicine, Taegu (Korea, Republic of)

2004-03-15

Several panoramic indices have been suggested to assess bone quality from the morphology and width of mandibular cortex on panoramic radiography. The purpose of this study was to compare dental implant failure group with control group in panoramic mandibular index (PMI), mandibular cortical index (MCI), and gonion index (GI) and to determine the effect of these panoramic indices on dental implant failure. A case-control study was designed. Test group (n = 42) consisted of the patients who had their implants extracted because of peri-implantitis. Control group (n = 139) consisted of the patients who retained their implants over one year without any pathologic changes and had been followed up periodically. They had dental implants installed in their mandibles without bone augmentation surgery from 1991 to 2001. The following measures were collected for each patients: 1) PMI, MCI, and GI were measured twice at one-week interval on preoperative panoramic views; and 2) age, sex, implant length, implant type, installed location, occluding dentition state, and complication were investigated from the chart record. The PMI showed moderate level of repeatability. The intra-observer agreement of MCI and GI were good. There was statistically significant difference in PMI between two groups. There were significant different patterns of distribution of MCI and GI between two groups. Among the panoramic indices, PMI and MCI showed significant correlation with dental implant failure. Panoramic indices can be used as reference data in estimating bone quality of edentulous patients who are to have implants installed in their mandibles.

The relationship between panoramic indices and dental implant failure

International Nuclear Information System (INIS)

Cho, Hyun Jung; Yi, Won Jin; Heo, Min Suk; Lee, Jin Koo; Lee, Sam Sun; Choi, Soon Chul; An, Chang Hyeon

2004-01-01

Several panoramic indices have been suggested to assess bone quality from the morphology and width of mandibular cortex on panoramic radiography. The purpose of this study was to compare dental implant failure group with control group in panoramic mandibular index (PMI), mandibular cortical index (MCI), and gonion index (GI) and to determine the effect of these panoramic indices on dental implant failure. A case-control study was designed. Test group (n = 42) consisted of the patients who had their implants extracted because of peri-implantitis. Control group (n = 139) consisted of the patients who retained their implants over one year without any pathologic changes and had been followed up periodically. They had dental implants installed in their mandibles without bone augmentation surgery from 1991 to 2001. The following measures were collected for each patients: 1) PMI, MCI, and GI were measured twice at one-week interval on preoperative panoramic views; and 2) age, sex, implant length, implant type, installed location, occluding dentition state, and complication were investigated from the chart record. The PMI showed moderate level of repeatability. The intra-observer agreement of MCI and GI were good. There was statistically significant difference in PMI between two groups. There were significant different patterns of distribution of MCI and GI between two groups. Among the panoramic indices, PMI and MCI showed significant correlation with dental implant failure. Panoramic indices can be used as reference data in estimating bone quality of edentulous patients who are to have implants installed in their mandibles.

Evaluation of dental erosion prevalence and contributing factors in patients referring to yazd dental school in 2012-2013

Directory of Open Access Journals (Sweden)

Farnaz Farahat

2016-03-01

Full Text Available Background and Aims: Dental erosion refers to the loss of tooth structure by being scratched chemically without bacterial involvement which needs to care about due to its prevalence and treatment problems. This study was designed with the aim of evaluation of the frequency of dental erosion and its causing factors in patients referring to yazd dental school in 2012-2013. Materials and Methods: In this cross-sectional study, 400 patients referring to yazd dental school were randomly selected. All of their teeth were evaluated in three surfaces (buccal, lingual and occlusal. The BEWE score was used for classification the extent of damages. Also, patients were given a questionnaire that included patient demographic information and questions to investigate the causes of dental erosion. Data were analyzed using SPSS version 17 and Mann-Whiney, Fisher exact, and Chi-square tests. Results: In this study, 138 men and 261 women were participated with the mean age of 33.26±10.83. 84 persons (21.1% had erosion. There was a direct and significant relationship between the dental erosion and patient's age (P >0.001. Also, there was a direct relationship between the dental erosion and reflux and consumption of lemon and pickle, beverages, soft beer and juice (P>0.001. Conclusion: Consumption of lemon and pickle, beverages, soft beer and juice increases the risk of erosion. Considering the prevalence of dental erosion in about 21% of patients, it is necessary to pay more attention to the knowledge of the causes of erosion and reduction strategies of it.

The effects of initial rise and axial loads on MEMS arches

KAUST Repository

Tella, Sherif Adekunle

2017-04-07

Arch microbeams have been utilized and proposed for many uses over the past few years due to their large tunability and bistability. However, recent experimental data have shown different mechanical behavior of arches when subjected to axial loads. This paper aims to investigate in depth the influence of the competing effects of initial rise and axial loads on the mechanical behavior of micromachined arches; mainly their static deflection and resonant frequencies. Based on analytical solutions, the static response and eigenvalue problems are analyzed for various values of initial rises and axial loads. Universal curves showing the variation of the first three resonance frequencies of the arch are generated for various values of initial rise under both tensile and compressive axial loads. This study shows that increasing the tensile or compressive axial loads for different values of initial rise may lead to either increase in the stiffness of the beam or initial decrease in the stiffness, which later increases as the axial load is increased depending on the dominant effect of the initial rise of the arch and the axial load. The obtained universal curves represent useful design tools to predict the tunability of arches under axial loads for various values of initial rises. The use of the universal curves is demonstrated with an experimental case study. Analytical formulation is developed to predict the point of minimum where the trend of the resonance frequency versus axial loads changes qualitatively due to the competing effects of axial loads and initial curvature.

Obesity and dental decay: inference on the role of dietary sugar.

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J Max Goodson

Full Text Available OBJECTIVE: To evaluate the relationship of children's obesity and dental decay. METHODS: We measured parameters related to obesity and dental decay in 8,275 4(th and 5(th grade Kuwaiti children (average age = 11.36 years in a cross-sectional study. First to determine body weight, height, age for computation of BMI . Second, to determine numbers of teeth, numbers of fillings and numbers of untreated decayed teeth to determine extent and severity of dental disease. From these measurements, we computed measures of dental decay in children from four body weight categories; obese, overweight, normal healthy weight and underweight children. RESULTS: The percentage of children with decayed or filled teeth varied inversely with the body weight category. The percentage of decayed or filled teeth decreased from 15.61% (n=193 in underweight children, to 13.03% (n=4,094 in normal healthy weight children, to 9.73% (n=1,786 in overweight children to 7.87% (n=2,202 in obese children. Differences between all groups were statistically significant. Male children in this population had more dental decay than female children but the reduction of tooth decay as a function of BMI was greater in male children. CONCLUSIONS: The finding of an inverse obesity-dental decay relationship contradicts the obesity-sugar and the obesity-dental decay relationship hypotheses. Sugar is well recognized as necessary and sufficient for dental decay. Sugar is also hypothesized to be a leading co-factor in obesity. If the later hypothesis is true, one would expect dental decay to increase with obesity. This was not found. The reasons for this inverse relationship are not currently clear.

Study on real working performance and overload safety factor of high arch dam

Institute of Scientific and Technical Information of China (English)

2008-01-01

Considering the fact that high arch dams have problems such as complicated stress,high cost,and hazards after being damaged,this paper intends to study the effects of load,material strength,and safety analysis method on dam safety and working performance of arch dams.In this article,the effects of temperature,self weight exaction way and water loading on structure response are first discussed,and a more reasonable way of considering is then put forward.By taking into consideration the mechanical property of materials and comparing the effects of different yield criteria on overloading safety of high arch dams,this paper concludes that brittle characteristics of concrete should be fully considered when conducting safety assessment for high arch dams to avoid overestimating the bearing capacity of the dams.By comparing several typical projects,this paper works out a safety assessment system of multiple safety and relevant engineering analogical analysis methods,which is closer to the actual situation,and thus is able to assess the response of high arch dam structure in a more comprehensive way,elicit the safety coefficients in different situations,and provide a new way of considering the safety assessment of high arch dams.

Dental implants for severely atrophied jaws due to ectodermal dysplasia

Directory of Open Access Journals (Sweden)

Preetha Balaji

2015-01-01

Full Text Available The aim was to present the successful esthetical and functional rehabilitation of partial anodontia in a case of severe ectodermal dysplasia with complete atrophy of the jaws. A 17-year-old male with Class III malocclusion with partial anodontia sought dental implant treatment. His expectation was that of Class I occlusion. The challenge in the case was to match the expectation, reality, and the clinical possibilities. Ridge augmentation was performed with a combination of rib graft and recombinant human bone morphogenetic protein-2. Simultaneously, 6 implants (Nobel Biocare™ - Tapered Groovy were placed in maxillary arch and 10 in the mandible. Simultaneous placement ensured faster and better osseointegration though a mild compromise of the primary stability was observed initially. After adequate healing, Customized Zirconia Procera™ system was used to build the framework. Zirconia crown was cemented to the framework. Radiological and clinical evidence of osseointegration was observed in all 16 dental implants. Successful conversion of Class III to Class I occlusion was achieved with the combination of preprosthetic alveolar ridge augmentation, Procera™ Implant Bridge system. Abnormal angulations and or placement of dental implants would result in failure of the implant. Hence conversion of Class III to Class I occlusion needs complete and complex treatment planning so that the entire masticatory apparatus is sufficiently remodeled. Planning should consider the resultant vectors that would otherwise result in failure of framework or compromise the secondary stability of the dental implant during function. A successful case of rehabilitation of complex partial anodontia is presented.

Dental care of patients after surgical therapy of inborn oro-facial clefts 3D technologies in diagnostics and therapy of cleft patients

OpenAIRE

Kašparová, Magdaléna

2015-01-01

Patients with orofacial defects, inborn or acquired, isolated or in combination with other handicaps in syndroms, suffer from various problems including psychological problems. Morphological changes within these handicaps burden not only the patients themselves, but also their families. Among the main problems are difficulties with feeding, speech or breathing. Anomalies in number or position of deciduous and permanent teeth, development of jaws and dental arches are often present. Multidisci...

Effective way to reconstruct arch bridges using concrete walls and transverse strands

Science.gov (United States)

Klusáček, Ladislav; Pěkník, Robin; Nečas, Radim

2017-09-01

There are more than 500 masonry arch bridges in the Czech Road system and about 2500 in the Czech Railway system. Many of them are cracked in the longitudinal (span) direction. The barrel vaults are separated by the cracks into partial masonry arches without load bearing connection in transverse direction. These constructions are about 150 years old and they are also too narrow for the current road system. This paper presents a strengthening method for masonry arch bridges using transverse post-tensioning. This method is very useful not only for strengthening in the transverse direction, but widening of masonry arches can be taken as secondary effect especially in case of road bridges. Several bridges were successfully repaired with the use of this system which seems to be effective and reliable.

Prosthetic status and prosthetic need among the patients attending various dental institutes of ahmedabad and gandhinagar district, gujarat.

Science.gov (United States)

Shah, Vrinda R; Shah, Darshana N; Parmar, Chaitanya H

2012-09-01

The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment form (1997). Prosthetic status and prosthetic treatment need was recorded. Out of 510, any type of Edentulousness was 322 (63 %). Among them, 254 (49.8 %) were partially edentulous while 68 (13.3 %) were completely edentulous. Only 69 (13 %) were having any prosthesis in upper arch while only 80 (16 %) were having any prosthesis in lower arch. Need for any type of prosthesis in upper and lower arch was 55 and 60 % in males and females, respectively. In lower social class group need of prosthesis in upper and lower arch was 62 and 63 %, respectively. It was found that prosthetic status and prosthetic treatment need increased with increase in age. Steps should be taken to overcome this disparity and more emphasis should be given to meet the felt need of the people through government and non government organizations to improve the oral health. The unmet prosthetic treatment need should be met to rehabilitate needy people so that their disability may be limited.

Cost of skid roads for arch logging in West Virginia

Science.gov (United States)

George R., Jr. Trimble; Carl R. Barr

1960-01-01

In the mountain hardwood country of the northern Appalachians, tree-length skidding with tractor and arch has proved to be economical logging. One essential part of this type of logging is that tree-length logs are winched to the skid roads: tractor and arch do not run around through the woods. Winching distance is commonly 200 to 300 feet; and occasionally an extra...

ŁPw Steel Arch Support – Designing and Test Results

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Marek Rotkegel

2013-01-01

Full Text Available Increasingly difficult geological-mining conditions make it necessary to seek new and effective ways of securing roadways. The new types of support must meet very high strength requirements and must have very high load-bearing capacities. These two conditions were taken into consideration when an ŁPw type steel arch support was designed. High strength of the arches was obtained through using steel of improved mechanical parameters, while high load-bearing parameters were obtained through shaping elements of the support arches. The works were conducted within the framework of the targeted research project no. 6ZR8 2008 C/07012 undertaken by Huta Łabędy SA, Institute for Ferrous Metallurgy and Central Mining Institute between 2010 and 2012.

Hypomineralized second primary molars: prevalence, defect characteristics and relationship with dental caries in Melbourne preschool children.

Science.gov (United States)

Owen, M L; Ghanim, A; Elsby, D; Manton, D J

2018-03-01

Dental caries and enamel defects (DDE) are prevalent amongst children. The presence of DDE, especially enamel hypomineralization, may increase caries experience. The reported prevalence of hypomineralized second primary molars (HSPM) is 2.7-21.8%, although the occurrence in Australian children remains unknown. These HSPM represent a potential predictive factor for molar-incisor hypomineralization (MIH). In total, 623 children aged 3-5 years from 30 randomly selected kindergartens participated. The HSPM were recorded using an index combining the European Academy of Paediatric Dentistry MIH Judgment Criteria and modified DDE Index. Caries was recorded using International Caries Detection and Assessment System criteria. In total, 144 HSPM were observed in 88 of the 623 (14.1%) children, a tooth-level prevalence of 5.8%. The prevalence of dentinal carious lesions was 13.2%, and caries prevalence (d 2-6 mft > 0) was 36.4%. Cavitated carious lesions affected 30.7% of HSPM. The relationship between an increase in HSPM lesion extent and increasing number of HSPM per child was statistically significant. A positive association between HSPM severity and extent at tooth level existed (P < 0.05). There was a positive relationship between the extent of HSPM and carious lesion severity (P < 0.05). In this population, children with HSPM did not have overall greater caries experience. © 2017 Australian Dental Association.

High fear of intra-oral injections: prevalence and relationship to dental fear and dental avoidance among 10- to 16-yr-old children.

Science.gov (United States)

Berge, Karin G; Agdal, Maren L; Vika, Margrethe; Skeie, Marit S

2016-12-01

The present study aimed to: (i) estimate the prevalence of self-reported high fear of intra-oral injections, high blood-injury fear, and injection fear; (ii) explore the overlap between high fear of intra-oral injections and high fear of dental treatment; and (iii) evaluate the possible consequence of high fear of intra-oral injections in terms of avoidance of dental care. The sample included 1,441 subjects, 10- to 16-yr of age, attending elementary schools in a county of Norway. Data were collected using questionnaires that were completed in classrooms. The survey instruments used were the Intra-Oral Injection Fear-scale, the Children's Fear Survey Schedule-Dental Subscale, the Injection Phobia scale for children, and the Mutilation Questionnaire for children. In total, 13.9% of the children reported high intra-oral injection fear. A strong association was found between fear of intra-oral injections and dental fear. When an intra-oral injection was needed, 10.6% would avoid dental treatment. In multiple regression analysis, high intra-oral injection fear was found to be associated with avoidance of dental treatment (OR = 6.52; 95% CI: 3.99-10.67). It was concluded that high fear of intra-oral injections was prevalent and might lead to avoidance of necessary dental treatment. Hence, intra-oral injection fear should be addressed before treatment of dental fear. © 2016 Eur J Oral Sci.

Confronting shibboleths of dental education.

Science.gov (United States)

Masella, Richard S

2005-10-01

Shibboleths are common expressions presented as indisputable truths. When used in educational discussions, they reflect "motherhood and apple pie" viewpoints and tend to bring debate to a halt. Use of shibboleths may precede a desired imposition of "locksteps" in educational programming and are easily perceived as paternalistic by recipients. Nine shibboleths are presented as common beliefs of dental faculty and administrators. Evidence contradicting the veracity of the "obvious truths" is offered. The traditional "splendid isolation" of dentistry contributes to parochialism and belief in false shibboleths. Sound principles of higher and health professions education, student learning, and dental practice apply to dental education as to all health disciplines. Student passivity in dental education is not the best preparation for proficiency in dental practice. The master teacher possesses a repertoire of methodologies specific to meeting defined educational objectives. Active learning experiences bear close resemblances to professional duties and responsibilities and internally motivate future doctors of dental medicine. The difficulty in achieving curricular change leads to curricular entrenchment. Dentistry and dental education should not trade their ethical high ground for the relatively low ethical standards of the business world. Principles of professional ethics should govern relationships between dentists, whether within the dental school workplace or in practice. Suggestions are made on how to confront shibboleths in dental school settings.

Recurrent Pneumonia due to Double Aortic Arch

Directory of Open Access Journals (Sweden)

I. Sedighi

2012-04-01

Full Text Available Introduction: Pneumonia is one of the most common infections during childhood. In children with recurrent bacterial pneumonia complete evaluation for underlying factors is necessary. The most common underlying diseases include: antibody deficiencies , cystic fibrosis , tracheoesophageal fistula and increased pulmonary blood flow. Vascular ring and its pressure effect is a less common cause of stridor and recurrent pneumonia. Congenital abnormalities in aortic arch and main branches which form vascular ring around esophagus and trachea with variable pressure effect cause respiratory symptoms such as stridor , wheezing and recurrent pneumoniaCase Report: A 2 year old boy was admitted in our hospital with respiratory distress and cough . Chest x-Ray demonstrated right lobar pneumonia. He had history of stridor and wheezing from neonatal period and hospitalization due to pneumonia for four times. The patient received appropriate antibiotics. Despite fever and respiratory distress improvement, wheezing continued. Review of his medical documents showed fixed pressure effect on posterior aspect of esophagus in barium swallow. In CT angiography we confirmed double aortic arch.Conclusion: Double aortic arch is one of the causes of persistant respiratory symptom and recurrent pneumonia in children for which fluoroscopic barium swallow is the first non-invasive diagnostic method.(Sci J Hamadan Univ Med Sci 2012;19(1:70-74

Class III camouflage using skeletal anchorage and Pendex appliance.

Science.gov (United States)

Miguel, José Augusto M; Zanardi, Gustavo

2011-01-01

This case report describes the orthodontic treatment for a young female, aged 18 years 4 months, with a Class III malocclusion on the right side, with a combination of a posterior and anterior crossbite. Two rigid orthodontic mini-implants were placed in the retromolar region in order to move the entire lower arch distally with nickel-titanium coil springs. In addition, a Pendex appliance was used to create space and to improve the arch form and the transverse relationship. The active treatment period was 17 months. Normal overjet and overbite were obtained, and facial balance was improved. Although the cephalometric superimposition has demonstrated the effects of dental compensation, the final dental and facial results were satisfactory and stable after the second year in retention. Copyright © 2011 Società Italiana di Ortodonzia SIDO. Published by Elsevier Srl. All rights reserved.

Highly Tunable Electrothermally Actuated Arch Resonator

KAUST Repository

Hajjaj, Amal Z.; Ramini, Abdallah; Alcheikh, Nouha; Younis, Mohammad I.

2016-01-01

that after some electro-thermal voltage load, the third resonance frequency starts to become more sensitive to the axial thermal stress, while the first resonance frequency becomes less sensitive. These results can be used as guidelines to utilize arches

How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

Directory of Open Access Journals (Sweden)

Andreas Habertheuer

2015-01-01

Full Text Available Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP and retrograde cerebral perfusion (RCP. Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data.

How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

Science.gov (United States)

Habertheuer, Andreas; Wiedemann, Dominik; Kocher, Alfred; Laufer, Guenther; Vallabhajosyula, Prashanth

2015-01-01

Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA) or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP) and retrograde cerebral perfusion (RCP). Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data. PMID:26713319

[A case of the Hallermann-Streiff syndrome].

Science.gov (United States)

Higashi, M; Hara, M; Michimata, H; Nishimura, K; Kurihara, Y

1990-01-01

The Hallermann-Streiff Syndrome has been characterized and established according to 7 positive and 5 negative signs, which were described by François. We encountered an 11 year, 5 months old boy who had 7 positive symptoms of this syndrome in our clinic. In this study, we reported on this typical patient focusing on his dental view. 1) Prolonged retention of the primary teeth which involved microdontia were noted. Congenitally missing teeth were also seen. 2) The occlusal relationship indicated open bite, and also the mandibular function was impaired. 3) The measurements of the length and width of the dental arch were smaller than that of a normal subject, and the dental arch of the maxilla was V-shaped. 4) According to X-ray cephalometric analysis, (a) the dental calculus and the alveolar bone absorption were very evident. (b) abnormal morphologic of the glenoid fossa, mandibulars condyle and the neck of mandibula were seen. These conditions were very evident on the left side. 5) The growth obstade of the maxilla and mandibla and the left shift of the mandible were found. 6) According to histological study, enamel hypoplasia was noted.

Anomalous Origin of the Left Vertebral Artery from the Aortic Arch.

Science.gov (United States)

Einstein, Evan H; Song, Linda H; Villela, Natalia L A; Fasani-Feldberg, Gregory B; Jacobs, Jonathan L; Kim, Dolly O; Nathawat, Akshay; Patel, Devika; Bender, Roger B; Peters, Daniel F

2016-04-01

Anatomic anomalies of the aortic arch have implications for clinical practice if their significance is understood. Our case study involves a cadaveric finding of the left vertebral artery originating directly from the aortic arch. Although this anatomical variation has been documented, the prevalence of this anomaly may be generally underestimated. After noting this anomaly, we analyzed 27 cases and found that four female cadavers had the left vertebral artery originating from the aortic arch rather than the left subclavian artery. With a prevalence rate of 14.8%, it would seem that this anomaly is more significant than previously thought, which could have implications for surgical practice.

A new method of stabilizing zygomatic complex and arch fractures. a ...

African Journals Online (AJOL)

Background: Antral packing cannot support fractures of the zygomatic arch properly because of the position, therefore the aim of this report was to document a new method by which both the zygomatic bone and arch can be stabilized. Method and Materials: Iodine soaked gauze was placed in the subzygomatic space ...

Variations of the aortic arch - a study on the most common branching patterns

International Nuclear Information System (INIS)

Muller, Marguerite; Schmitz, Bernd L; Schick, Melanie; Schloetzer, Wiebke; Pauls, Sandra; Roehrer, Stefan; Kapapa, Thomas

2011-01-01

Background: Anatomical variants of the aortic arch and its branching patterns often appear as an incidental finding during routine computed tomography (CT) scanning. These variations can be of relevance when performing angiography or endovascular interventions and may cause symptoms such as dysphagia. Purpose: To analyze common anatomical variations found within the arteries originating from the aortic arch in patients using contrast CT imaging techniques. Material and Methods: A total of 2033 contrast CT scans were analyzed. To obtain a truly representative sample, cases were chosen from different hospital departments without previous knowledge of the patient history. Results: The total percentage of variations within the analyzed patients was 13.3%. In 8.0% a truncus bicaroticus was found. 4.2% of the patients showed a left vertebral artery originating directly from the aortic arch, mostly proximal, and in 1 case distal to the left subclavian artery. In 1.0% we found an aberrant right subclavian artery. We also found a single case of a right descending aortic arch. Conclusion: Variations of the aortic arch and its branching are frequently found, mostly as an incidental finding during routine diagnostic scanning. A contrast-enhanced CT scan is a good method with which to study the aortic arch and its associated branching pattern

Variations of the aortic arch - a study on the most common branching patterns