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Sample records for incisor inclination positional

  1. Incisor inclination and perceived tooth colour changes.

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    Ciucchi, Philip; Kiliaridis, Stavros

    2017-10-01

    Social attractiveness is influenced by a variety of different smile-related factors. We evaluated whether the degree of upper central incisor proclination can result in tooth colour change. Forty young adult subjects (20-25 years) in good health with a complete sound dentition were selected. The subjects were seated in standardized light conditions with an above-directed light source. Their natural head position was stated as 0 degrees. To mimic the range of possible anterior torque movements they were asked to tilt their heads upward +15 degrees (upward tilting) and downward -15 degrees (downward tilting). Frontal macro photographs, parallel to the Frankfort plane of the patient's natural head position were taken at the three head angulations (+15, 0, and -15 degrees ). Photographs were analysed for colour differences at the centre of the incisor clinical crowns with a CIE L*a*b* colour model based software. A paired t-test was used to test for significance between each value for each inclination. Differences were found between the CIE L*a*b* colour values for: upward tilting, downward tilting, and -15 to +15 degrees (total tilting) except for b* values for downward tilting. As the inclination of the subject's head changed downward, the upper incisors were retroclined and the CIE L*a*b* values indicated a darker and less green but redder colour component. As the inclination of the subject's head changed upwards the upper incisors were proclined and the L*a*b* values indicated a lighter and less green and yellow but redder and bluer colour component. Proclination of upper incisors caused lighter tooth colour parameters compared to retroclined incisors and colour changes. Orthodontic change of upper incisor inclination may induce alterations on how tooth colour is perceived.

  2. A jig for measuring incisor inclination.

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    Shah, N; Spary, D J; Rock, W P

    2005-06-01

    The aim of this study was to design and construct a jig for measuring the inclination of the upper incisors to the maxillary plane and of the lower incisors to the mandibular plane. After several prototypes had been tested, the required properties for a successful jig were identified and a simple inexpensive device was produced. Measurements obtained when using the jig on 51 subjects were compared with cephalometric values by means of regression analysis. This revealed that measurements obtained using the jig against the upper and then the lower incisor crowns could be converted to cephalometric incisor angulations with 96 per cent accuracy to 10 degrees, by adding 23 and 3 degrees, respectively. The jig was accurate to 5 degrees on 69 per cent of occasions for the upper teeth. The 5 degrees accuracy with the lower incisors was only 27 per cent, although over a 6 degree range it improved to 78 per cent. For upper and lower tooth measurements combined, the jig was accurate to within 6 degrees on 75 per cent of occasions.

  3. Upper incisors' positions after extraction.

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    Werneck, Eduardo César; Mattos, Fernanda Silva; Cotrim-Ferreira, Flávio Augusto; Prado, Renata Falchete; Silva, Márcio Garcia; Araújo, Adriano Marotta

    2014-01-01

    The aim of this research was to verify the amount of horizontal and vertical movement and incisor inclination of upper incisors and correlate these with Edgewise and Alexander brackets use and the presence of overbite during anterior retraction in sliding mechanics. The sample was composed of 40 adult patients divided into 2 groups, treated with Edgewise and Alexander brackets (20 each) subdivided in 2 groups (10 each), according to the presence or absence of deep bite. Treatment consisted of 4 extraction cases with sliding mechanics with the 2 different brackets. Pre- and post-treatment cephalograms were measured and the values of interest submitted to descriptive statistical analysis, ANOVA at 5%, the Tukey test and Pearson's correlation. Upper incisor retraction was not related to the brackets used nor to the presence of deep bite, though lingual tipping was greater when Edgewise brackets were used and deep bite was absent. No statistically significant differences in upper incisor vertical movements were observed and no correlation was determined between upper incisor intrusion and lower incisor labial tipping in overbite correction or in upper incisor retraction and lower incisor labial tipping for overjet correction. Bracket prescription and its interaction with deep bite were significant and Edgewise brackets without deep bite showed the worst inclination control. It was concluded that bracket prescriptions are important to increase control of sliding mechanics.

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

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    Hassan, S.; Shaikh, A.; Fida, M.

    2015-01-01

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

  5. Incisor inclination determined by the light reflection zone on the tooth's surface.

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    Brezniak, Naphtali; Turgeman, Ronit; Redlich, Meir

    2010-01-01

    Maxillary incisors are the most prominent teeth, and their inclination plays an important role in esthetics. In orthodontics, the inclination of central incisors is usually determined by cephalometric analysis. This publication suggests an adjunctive clinical measure to determine this inclination. The objective of the study was to examine the correlation between the inclinations of maxillary incisors measured on a cephalometric lateral headfilm and the light reflection zone appearing on the buccal surface of the teeth on anterior intraoral photographs. Maxillary incisor inclination, divided into three levels-proclination, normal inclination, and retroclination-of 65 patients was determined by means of cephalometric analysis, using three angular measurements (maxillary incisor to sella-nasion, maxillary incisor to Frankfort horizontal, and maxillary incisor to nasion-point A). The anterior intraoral photographs of the 65 patients were divided into 3 groups according to the reflection zone on the maxillary central incisors as determined from the photographs: incisal, middle, and gingival. The correlation and agreement between the two parameters were evaluated by chi-square and kappa statistics. The light reflection zone on the tooth surface as it appears on intraoral photographs-incisal, middle, or gingival-correlated with statistical significance to the angular inclination of the teeth-proclination, normal inclination, and retroclination, respectively-as determined by means of cephalometric analysis (P light reflection zone viewed on the buccal surface of intraoral photographs. This method might be used as a new screening tool and further as an additional clinical tool for assessing treatment plans in orthodontics and other fields of dentistry.

  6. Coordinating bracket torque and incisor inclination : Part 3: Validity of bracket torque values in achieving norm inclinations.

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    Zimmer, Bernd; Sino, Hiba

    2018-03-19

    To analyze common values of bracket torque (Andrews, Roth, MBT, Ricketts) for their validity in achieving incisor inclinations that are considered normal by different cephalometric standards. Using the equations developed in part 1 (eU1 (BOP) = 90° - BT (U1) - TCA (U1) + α 1 - α 2 and eL1 (BOP) = 90° - BT (L1) - TCA (L1) + β 1 - β 2 ) (abbreviations see part 1) and the mean values (± SD) obtained as statistical measures in parts 1 and 2 of the study (α 1 and β 1 [1.7° ± 0.7°], α 2 [3.6° ± 0.3°], β 2 [3.2° ± 0.4°], TCA (U1) [24.6° ± 3.6°] and TCA (L1) [22.9° ± 4.3°]) expected (= theoretically anticipated) values were calculated for upper and lower incisors (U1 and L1) and compared to targeted (= cephalometric norm) values. For U1, there was no overlapping between the ranges of expected and targeted values, as the lowest targeted value of (58.3°; Ricketts) was higher than the highest expected value (56.5°; Andrews) relative to the bisected occlusal plane (BOP). Thus all of these torque systems will aim for flatter inclinations than prescribed by any of the norm values. Depending on target values, the various bracket systems fell short by 1.8-5.5° (Andrews), 6.8-10.5° (Roth), 11.8-15.5° (MBT), or 16.8-20.5° (Ricketts). For L1, there was good agreement of the MBT system with the Ricketts and Björk target values (Δ0.1° and Δ-0.8°, respectively), and both the Roth and Ricketts systems came close to the Bergen target value (both Δ2.3°). Depending on target values, the ranges of deviation for L1 were 6.3-13.2° for Andrews (Class II prescription), 2.3°-9.2° for Roth, -3.7 to -3.2° for MBT, and 2.3-9.2° for Ricketts. Common values of upper incisor bracket torque do not have acceptable validity in achieving normal incisor inclinations. A careful selection of lower bracket torque may provide satisfactory matching with some of the targeted norm values.

  7. Mandibular incisor position changes do not explain increase in keratinized gingiva height after periodontally accelerated osteogenic orthodontics

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    Donald J Ferguson

    2017-01-01

    Full Text Available Purpose: This study aimed to reexamine the relationship between mandibular incisor inclination, prominence and vertical changes in position, and keratinized gingival tissue (KT height changes labial to the mandibular incisors after orthodontic treatment with and without augmented corticotomy (Cort. Materials and Methods: Two orthodontically treated groups of 35 individuals each, with (Cort and without (conventional [Conv] alveolar decortication and augmentation bone grafting (periodontally accelerated osteogenic orthodontics [PAOO], were matched for sample size, gender, mandibular premolar extractions, pretreatment age, posttreatment observation period, and pretreatment KT height in this case–controlled retrospective study. Pre- and post-treatment lateral cephalometric radiographs were evaluated for mandibular incisor vertical, inclination, and prominence changes. Results: As reported previously (Wilcko 2015, KT height had significantly increased by 0.78 mm (P = 0.001 in the Cort group and decreased by 0.38 mm (P = 0.002 in Conv on an average of 1.5 years after completion of active orthodontic therapy. In this study, Cort mandibular incisors proclined and protruded significantly during therapy while Conv incisors did not. Changes in mandibular incisor inclination and prominence explained neither the decrease in keratinized gingiva height in Conv nor the KT height gain in Cort. Conclusions: In spite of mandibular incisor proclination and protrusion, orthodontic therapy combined with alveolar decortication and augmentation bone grafting resulted in a clinically significant increase in keratinized gingiva height 1.5 years' posttreatment.

  8. Analysis of the root position of the maxillary incisors in the alveolar bone using cone-beam computed tomography

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    Jung, Yun Hoa; Cho, Bong Hee [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Pusan National University, Yangsan (Korea, Republic of); Hwang, Jae Jun [Dept. of Oral and Maxillofacial Radiology, Yonsei University College of Dentistry, Seoul (Korea, Republic of)

    2017-09-15

    The purpose of this study was to measure the buccal bone thickness and angulation of the maxillary incisors and to analyze the correlation between these parameters and the root position in the alveolar bone using cone-beam computed tomography (CBCT). CBCT images of 398 maxillary central and lateral incisors from 199 patients were retrospectively reviewed. The root position in the alveolar bone was classified as buccal, middle, or palatal, and the buccal type was further classified into subtypes I, II, and III. In addition, the buccolingual inclination of the tooth and buccal bone thickness were evaluated. A majority of the maxillary incisors were positioned more buccally within the alveolar bone, and only 2 lateral incisors (0.5%) were positioned more palatally. The angulation of buccal subtype III was the greatest and that of the middle type was the lowest. Most of the maxillary incisors exhibited a thin facial bone wall, and the lateral incisors had a significantly thinner buccal bone than the central incisors. The buccal bone of buccal subtypes II and III was significantly thinner than that of buccal subtype I. A majority of the maxillary incisor roots were positioned close to the buccal cortical plate and had a thin buccal bone wall. Significant relationships were observed between the root position in the alveolar bone, the angulation of the tooth in the alveolar bone, and buccal bone thickness. CBCT analyses of the buccal bone and sagittal root position are recommended for the selection of the appropriate treatment approach.

  9. Influence of dental chair backrest inclination on the registration of the mandibular position.

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    Coelho, Mariana Freire; Cavalcanti, Bruno das Neves; Claro Neves, Ana Christina; Jóias, Renata Pilli; Rode, Sigmar de Mello

    2015-11-01

    Varying the inclination of the dental chair backrest might alter the distribution of occlusal contact points. The purpose of this study was to identify the influence of backrest inclination on the registration of the mandibular position. Ten participants aged between 18 and 30 years with a complete permanent dentition, uncompromised motor function, no tooth mobility, and no temporomandibular disorders were selected. To register interocclusal contacts, an autopolymerizing methylmethacrylate device was adapted to the maxillary anterior teeth and a composite resin increment was added to the mandibular central incisors. Contacts were registered with the following variations in the inclination of the dental chair backrest: 90 degrees, 120 degrees, and 180 degrees. A standardized digital photograph was made of each mark in each backrest position, and the images were superimposed to measure the distances in registration from 90 to 120 and from 90 to 180 degrees. Data were analyzed with the Student paired t test (α=.05). When the chair was inclined from the 90-degree to the 120-degree position, the mandible was repositioned posteriorly by a mean of 0.67 mm, but the difference was not statistically significant. When the chair was inclined from the 90-degree to the 180-degree position, however, the mandible was repositioned posteriorly by a statistically significant mean of 1.41 mm. Mandibular position is influenced by increasing inclination, and this influence was statistically significant at a 180-degree incline. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  10. Preplanning contemporary incisor positioning using inclinometer: A clinical and cephalometric study

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    Saurabh Birla

    2014-01-01

    Conclusion: Third-order measurements using inclinometer device can offer a simple way to get an objective and rapid vision of the incisors inclination and might be a helpful guideline to the choice of low or high torque brackets. Incisor inclination is strongly correlated with skeletal-sagittal data, but little with skeletal-vertical findings.

  11. Evaluation of the lower incisor inclination during alignment and leveling using superelastic NiTi archwires: a laboratory study

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    Carolina Baratieri

    2012-06-01

    Full Text Available OBJECTIVE: The aim of this laboratory study is to evaluate the influence of the shape and the length limitation of superelastic nickel-titanium (NiTi archwires on lower incisors inclination during alignment and leveling. METHODS: Metal teeth mounted on a typodont articulator device were used to simulate a malocclusion of the mandibular arch (-3.5 mm model discrepancy. Three different shapes (Standard, Accuform and Ideal of superelastic NiTi archwires (Sentalloy, GAC, USA were tested. Specimens were divided in two groups: Group I, with no limitation of the archwire length; and Group II, with distal limitation. Each group had thirty specimens divided into three subgroups differentiated by the archwire shape. All groups used round wires with diameters of 0.014-in, 0.016-in, 0.018-in and 0.020-in. The recording of all intervals was accomplished using standardized digital photographs with orthogonal norm in relation to median sagittal plane. The buccolingual inclination of the incisor was registered using photographs and software CorelDraw. RESULTS: The results were obtained using ANOVA and Tukey's test at a significant level of 5%. The inclination of the lower incisor increased in both groups and subgroups. The shape of the archwire had statistically significant influence only in Group I - Standard (11.76º, Ideal (5.88º and Accuform (1.93º. Analyzing the influence of the length limitation, despite the mean incisor tipping in Group II (3.91º had been smaller than Group I (6.52º, no statistically significant difference was found, except for Standard, 3.89º with limitation and 11.76º without limitation. The greatest incisor tipping occurred with the 0.014-in archwires.

  12. Mesiodistal inclination of the unerupted second premolar in the mandible of Japanese orthodontic patients with incisor agenesis.

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    Kure, Kenichi; Arai, Kazuhito

    2015-11-01

    To elucidate the mesiodistal inclination of the unerupted mandibular second premolar (MnP2) in cases of mandibular incisor (MnIc) agenesis and unilateral MnP2 agenesis. Twenty-two cases of unilateral MnP2 agenesis (MnP2 agenesis group) and a control group (control group A) of 22 cases without permanent tooth agenesis excluding third molars were selected. Thirty-six cases of MnIc agenesis (MnIc agenesis group) and another control group (control group B) of 36 subjects were also selected. Mesiodistal inclination of the unerupted MnP2 on the panoramic X-rays was measured according to the distal angle and premolar-molar angle using the methods of Shalish et al. and Baccetti et al., respectively. Differences in mean values of the angular measurements between agenesis groups and corresponding controls were investigated (unpaired t-test). In the MnP2 agenesis group, the mean distal angle decreased 12.3° and the mean premolar-molar angle increased 13.3° for the MnP2 compared with control group A (both P agenesis group, no significant differences in the means of those angles for the MnP2 were found when compared with control group B. In Japanese orthodontic patients, there is a relationship between unilateral MnP2 agenesis and the mesiodistal angulation of the unerupted MnP2. However, no significant relationship was observed between MnIc agenesis (which relationship is often seen in Asian populations) and the position of the unerupted MnP2. These results suggest that different genetic factors are involved in MnP2 agenesis and MnIc agenesis.

  13. Molar heights and incisor inclinations in adults with Class II and Class III skeletal open-bite malocclusions.

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    Arriola-Guillén, Luis Ernesto; Flores-Mir, Carlos

    2014-03-01

    The aim of this research was to compare maxillary and mandibular molar heights and incisor inclinations in patients with skeletal open-bite Class II, patients with skeletal open-bite Class III, and an untreated control group. Pretreatment lateral cephalograms of 70 orthodontic patients (34 men, 36 women) between 16 and 40 years of age were examined. The sample was divided into 3 groups according to facial growth pattern and overbite. The control group (n = 25) included normodivergent Class I subjects with adequate overbite; the skeletal open-bite Class II group (n = 25) and the skeletal open-bite Class III group (n = 20) included hyperdivergent Class II or Class III subjects with negative overbite. Measurements considered were ANB angle, palatal and mandibular plane angles, maxillary incisor palatal plane angulation, and mandibular incisor mandibular plane angulation, as well as the distance from the palatal or the mandibular plane to the mesial cusp of the molars. Multivariate analysis of covariance and multivariate analysis of variance tests were used to determine the differences between the groups, followed by the Tukey post-hoc test. Additionally, the Mann-Whitney U test and Kruskall-Wallis test were performed. Significant differences in molar height were found (P open-bite and control groups was found. Mandibular molar height was greater in the skeletal open-bite Class II group (P open-bite Class III group by approximately 6°. Mandibular incisor to mandibular plane angulation was 10° more lingual in the skeletal open-bite Class III group (P open-bite groups had greater molar heights than did the control group. The skeletal open-bite Class II group had more eruption of the mandibular molars. The maxillary incisors were more proclined and the mandibular incisors were more lingual in the skeletal open-bite Class III group. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  14. Coordinating bracket torque and incisor inclination : Part 2: Reproducibility and statistical measures of the torque coordination angle (TCA).

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    Sino, H; Zimmer, B; Schelper, I; Schenk-Kazan, S; Streibelt, F

    2018-03-09

    To determine the reproducibility and statistical measures of the torque coordination angle (TCA). A total of 107 final cephalograms and corresponding casts were included, all reflecting treatment outcomes that met high qualitative standards, one of them being a Peer Assessment Rating (PAR) score of ≤3. Based on these records, the TCA was measured as a parameter to identify differences related to tooth morphology and bracket position between the torque-relevant reference plane at the bracket base and the long axis of a tooth. All measurements were performed on upper and lower central incisors (U1 and L1). Several reproducibility assessments for the TCA measurements yielded good results, including objectivity at 1.26 ± 0.81° (U1) or 1.41 ± 1.18° (L1), examiner reliability at 1.30 ± 0.97° (U1) or 1.25 ± 0.82° (L1), and method reliability at 1.80 ± 1.13° (U1) or 1.53 ± 1.07° (L1). The statistical measures revealed a high degree of interindividual variability. With bracket placement 4.5 mm (U1) or 4.0 mm (L1) above the incisal edge, the differences between the maximum and minimum TCA values were similarly large in both jaws (21.0° for U1 or 20.0° for L1), given mean TCA values of 24.6 ± 3.6° (U1) or 22.9 ± 4.3° (L1). Moving the bracket placement from 3.5 to 5.5 mm (U1) or from 3.0 to 5.0 mm (L1) changed the mean TCA values by 4.5° (U1) or 3.2° (L1). The TCA is a suitable cephalometric parameter to identify differences related to tooth morphology and bracket placement. Given its high interindividual variability, the fixed torque value of a specific bracket system should not be expected to produce the same incisor inclinations across patients.

  15. Exploration of variations in positions of upper and Lower incisors, overjet, overbite, and irregularity Index in orthodontic patients with dissimilar depths of Curve of spee.

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    Kumari, Nita; Fida, Mubassar; Shaikh, Attiya

    2016-01-01

    The position and arrangement of teeth as well as the entire scheme of occlusion differs from one individual to the other .The purpose of this study was to examine differences in position and inclination of incisors, overjet, overbite and lower arch crowding in subjects with different depths of curve of Spee and to determine correlations between depth of curve of Spee and these variables. The sample comprised of 114 patients (55 females and 59 males) with fully erupted permanent second molars (age 12-25 years), having no history of previous orthodontic treatment, no craniofacial anomalies, and no missing permanent teeth. Study parameters were assessed by using pretreatment lateral cephalograms and dental casts of orthodontic patients. The entire sample was divided into three groups according to depth of curve of Spee (mild Spee=38, moderate Spee=38, severe Spee=38). Descriptive statistics were calculated. Differences between the Spee groups were assessed by analysis of variance. In addition, correlation coefficients were calculated between curve of Spee and other parameters. Statistically significant differences were found in upper incisor inclination (p=0.000), lower incisor inclination (p=0.003), Steiner's mandibular plane angle (p=0.000), overjet (p=0.001), overbite (p=0.000) and irregularity index (p=0.008) among the Spee groups. Moreover, statistically significant positive correlations were found between curve of Spee and overjet, overbite and irregularity index. Upper and lower incisor inclinations as well as mandibular plane angle were found to have statistically significant but negative correlations with curve of Spee. Overjet and overbite in severe Spee group are larger than in mild and moderate Spee groups. There is negative correlation between curve of Spee depth and inclinations of upper and lower incisors. There is positive correlation between curve of Spee depth and severity of lower anterior crowding and Steiner's mandibular plane angle.

  16. The relationship between the incisor position and lingual surface morphology in normal occlusion.

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    Hasegawa, Yuh; Ezura, Akira; Nomintsetseg, Batbayar

    2017-01-01

    This study aimed to investigate the relationship between the morphological characteristics of maxillary incisors and the anterior occlusion. The study materials comprised dental casts and lateral cephalograms of 26 modern Mongolian females with Angle Class I normal occlusion (mean age, 21 years 5 months). Computed tomography (CT) images of the dental casts were taken with an X-ray micro-CT system (SMX-100CT, Shimadzu, Kyoto Japan). The thickness of the marginal ridges and incisal edges, and the overjet and overbite, was measured on the three-dimensional images of the dental casts. On the lateral cephalogram, maxillary incisor to sella-nasion plane angle (U1 to SN angle), maxillary incisor to nasion-point A plane distance (U1 to NA distance), mandibular incisor to nasion-point B plane distance (L1 to NB distance), incisor mandibular plane angle, and interincisal angle were measured by tracing the left incisors of the maxilla and mandible. Spearman's single rank correlation coefficients were used to investigate any correlation between measurement items for each maxillary incisor. The thickness of the marginal ridges and incisal edges was positively correlated with the overbite. The thickness of the incisal edges was positively correlated with the irregularity index of the maxilla. There were significant negative correlations between overbite and U1 to SN angle, U1 to NA distance, and L1 to NB distance. Significant positive correlations were noted between the overbite and the overjet. In conclusion, there was no strong relationship between the morphological characteristics of maxillary incisors and the anterior occlusion.

  17. Vertical growth-related changes in the positions of palatal rugae and maxillary incisors.

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    Christou, Panagiotis; Kiliaridis, Stavros

    2008-01-01

    With 3-dimensional scanning, the image of 1 digital dental cast can be superimposed on another to observe growth or treatment changes; however, this requires stable references. The palatal rugae were considered reliable points for detecting dental changes on the cast's occlusal plane, but is this the case in the vertical plane? Our aims were to assess the long-term stability of the palatal rugae in the vertical dimension, relate them to possible maxillary incisor posteruptive movements, and validate them as references for the evaluation of longitudinal dental changes. Four-year longitudinal lateral cephalograms and dental casts of 10 adults and 13 adolescents were used. The median palatal contour of each cast and marks corresponding to each ruga were superimposed on the palate of the cephalograms. Changes in rugae positions during the observation period were measured with respect to the palatal plane. Vertical changes were greater for the first rugae (closest to the incisors), less for the second, and even less for the third (farthest from the incisors). The adolescents showed greater vertical changes in rugae position than the adults. There were no statistically significant differences in the anteroposterior changes between the groups. The maxillary central incisor and the first ruga had vertical displacements proportional to the increase of the subject's lower anterior facial height. We found vertical displacement of the maxillary incisor and the rugae during the 4 years of observation in adolescents and adults. The third ruga, the farthest from the incisors, can be used as a reliable reference to assess longitudinal dental changes mainly when growth changes are less prominent.

  18. Inclined head position improves dose distribution during hippocampal-sparing whole brain radiotherapy using VMAT

    International Nuclear Information System (INIS)

    Kim, Kyung Su; Seo, Suk-Jin; Lee, Jaegi; Kim, Eunji; Choi, Noorie; Seok, Jin-Yong; Hong, Joo Wan; Chung, Jin-Beom; Eom, Keun-Yong; Kim, Jae-Sung; Kim, In Ah

    2016-01-01

    Hippocampal-sparing whole brain radiotherapy (HS-WBRT) aims to preserve neurocognitive functions in patients undergoing brain radiotherapy (RT). Volumetric modulated arc therapy (VMAT) involves intensity-modulated RT using a coplanar arc. An inclined head position might improve dose distribution during HS-WBRT using VMAT. This study analyzed 8 patients receiving brain RT with inclined head positioning. A comparable set of CT images simulating a non-inclined head position was obtained by rotating the original CT set. HS-WBRT plans of coplanar VMAT for each CT set were generated with a prescribed dose of 30 Gy in 10 fractions. Maximum dose to the hippocampi was limited to 16 Gy; to the optic nerve, optic chiasm, and eyeballs this was confined to less than 37.5 Gy; for the lenses to 8 Gy. Dosimetric parameters of the two different plans of 8 patients were compared with paired t-test. Mean inclined head angle was 11.09 ± 0.73 . The homogeneity (HI) and conformity (CI) indexes demonstrated improved results, with an average 8.4 ± 10.0 % (p = 0.041) and 5.3 ± 3.9 % (p = 0.005) reduction, respectively, in the inclined vs. non-inclined position. The inclined head position had lower hippocampi D min (10.45 ± 0.36 Gy), D max (13.70 ± 0.25 Gy), and D mean (12.01 ± 0.38 Gy) values vs. the non-inclined head position (D min = 12.07 ± 1.07 Gy; D max = 15.70 ± 1.25 Gy; D mean = 13.91 ± 1.01 Gy), with 12.8 ± 8.9 % (p = 0.007), 12.2 ± 6.8 % (p = 0.003), and 13.2 ± 7.2 % (p = 0.002) reductions, respectively. Mean D max for the lenses was 6.34 ± 0.72 Gy and 7.60 ± 0.46 Gy, respectively, with a 16.3 ± 10.8 % reduction in the inclined position (p = 0.004). D max for the optic nerve and D mean for the eyeballs also decreased by 7.0 ± 5.9 % (p = 0.015) and 8.4 ± 7.2 % (p = 0.015), respectively. Inclining the head position to approximately 11 during HS-WBRT using VMAT improved dose distribution in the planning target volume and allowed lower doses to the hippocampi and

  19. A labially positioned mesiodens and its repositioning as a missing central incisor.

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    Ephraim, Rena; Dilna, N C; Sreedevi, S; Shubha, M

    2014-09-01

    Hyperdontia is an increased number of teeth within the dental arches. This is of particular interest to pediatric dentists who commonly make the initial diagnosis. Most often a large portion of these teeth is completely embedded or impacted within the jaws and can be viewed only radiographically. Hyperdontia can occur on virtually every tooth-bearing surface. However, the most frequent is the mesiodens, in the anterior maxillary region. Anterior maxillary teeth are one of the most important features contributing to aesthetics of an individual. Missing anterior teeth can cause undue psychological stress in children, during their growing years. Most of the literature available show that the mesiodens are situated on the palatal aspect of the permanent incisors. Their treatment frequently involves an early recognition, extraction through a traditional palatal technique and guiding the associated permanent tooth to its original position. The purpose of this article is to enlighten the clinician of the need of deviating from the traditional approach of early extraction in particular situations and to conserve the mesiodens if favorable as an alternative treatment to a malformed permanent tooth, which may fail to erupt. This report describes a successful multidisciplinary approach to treatment of a unerrupted, labially placed mesiodens in conjunction with a dilacerated and impacted permanent tooth, in a child with a missing left central incisor. Treatment consisted of localizing and confirming the placement of the mesiodens to be labial, surgically exposing the crown of the mesiodens through a labial surgical approach, orthodontically guiding it to the position of the missing central incisor, extracting the malformed permanent incisor, and restoring the mesiodens to the required anatomy with composites, to establish aesthetics and function of the affected region.

  20. Lateral incisor root resorption and active orthodontic treatment in the early mixed dentition.

    Science.gov (United States)

    Amlani, M S; Inocencio, F; Hatibovic-Kofman, S

    2007-12-01

    To evaluate the presence of root resorption in the lateral incisor after active orthodontic treatment in the early mixed dentition. Twenty-six children treated at the Children's Clinic of the Schulich School of Medicine and Dentistry at the University of Western Ontario were examined radiographically for lateral incisors root resorption before and after early active treatment to align upper incisors (2 x 4 appliance). In addition, canine inclinations to the midline and to the long axis of the lateral incisor as well as the most medial position of the canine crown were measured as potential risk factors for root resorption. 8% (4) of the lateral incisors exhibited root resorption and the mean crown-to-root ratio of these teeth was significantly higher than that for lateral incisors not exhibiting root resorption. Similarly, mean canine inclinations to the midline and to the long axis of the lateral incisor were also significantly higher for the root resorption group. No association could be found between the most medial position of the canine crown and root resorption in the lateral incisor. This study showed that active orthodontic treatment in the early mixed dentition does not increase the risk for root resorption in the lateral incisors as long as the clinician takes into consideration canine inclinations and their potential effect on root resorption. Limitations inherent to radiographic assessment are acknowledged.

  1. Influence of the vertical position of maxillary central incisors on the perception of smile esthetics among orthodontists and laypersons.

    Science.gov (United States)

    Machado, Andre Wilson; McComb, Ryan W; Moon, Won; Gandini, Luiz Gonzaga

    2013-12-01

    The purpose of this study was to determine the perception of smile esthetics among orthodontists and laypeople with respect to different upper central incisor vertical positions in a frontal smile analysis. A frontal close-up smile photo of an adult Caucasian woman was selected. The patient had healthy upper anterior dentition and had no history of orthodontic treatment. Images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. All images were assessed in three different views: full smile, gingival close-up excluding incisal edges, and incisal close-up excluding gingival margins. Images were randomly assembled in an album, which was given to 120 judges: 60 orthodontists and 60 laypersons. Each rater was asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were then statistically analyzed. The highest rated smiles showed two notable characteristics: the central-to-lateral incisal step was 1.5 mm; and the central incisor gingival margins matched the laterals, and both were 0.5 mm below the line of the canine gingival margins. The least attractive smile was the one with no step between the centrals and laterals, and with the central incisor gingival margins 1.0 mm above the canine gingival margins. The results of this study indicate that slightly extruded upper central incisors are more esthetically preferred than intruded. The upper central incisors are the key determinant in evaluating smile esthetics, and thus, the assessment of their ideal vertical positioning is an aspect of paramount importance. © 2013 Wiley Periodicals, Inc.

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

    Directory of Open Access Journals (Sweden)

    Mukesh Singhal

    2012-01-01

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

  3. Surgical and Orthodontic Management of Central Permanent Incisor Impacted in Ectopic Position: a Case Report

    OpenAIRE

    Truque Martínez, Óscar Gerardo; Universidad El Bosque; Longlax Triana, María Carolina; Universidad El Bosque; Bendahan Alvarez, Zita Carolina; Ramírez Rodríguez, Katherine

    2014-01-01

    The incidence of impacted incisor teeth is 4%. This article presents the case of a 9-year-old female patient who was referred to the postdoctoral pediatric dentistry clinic at the University El Bosque for extraction of an upper central incisor with a history of dentoalveolar trauma at age seven and surgical window to allow eruption of tooth 21. The retention of tooth 11 was confirmed through clinical examination, X-ray analysis, and computerized axial tomography scan. The treatment included p...

  4. Influence of patient head positioning on measured axial tooth inclination in panoramic radiography.

    Science.gov (United States)

    Hardy, Timothy C; Suri, Lokesh; Stark, Paul

    2009-06-01

    Panoramic radiographs are routinely used to assess the mesiodistal axial inclination of teeth (MDAI) in orthodontic treatment. These radiographs are sensitive to minor deviations from standard head position that result in image distortions. The aim of this study is to measure and quantify the changes in MDAI on panoramic radiograph resulting from changes in patient head position. The testing devise was a human skull with guide wires placed on the facial surface of the teeth and alveolar process along the long axis of each tooth. Panoramic radiographs were captured digitally with the orientation of the skull in Frankfurt horizontal plane parallel to the floor and with 1 degrees , 2 degrees , 5 degrees , 7 degrees , and 10 degrees both superior and inferior rotations. The mesiodistal tooth angulations were determined using MIPAC software (DentalEye and LEAD Technologies, Inc. 2005). The more distal the position of the tooth in the arch the greater the change in MDAI with a change in vertical head position. A maximum change of approximately 10 degrees was observed in MDAI of both the maxillary and mandibular molars with a corresponding superior head tilt of 10 degrees. The Mandibular anteriors displayed significant inconsistencies in MDAI with both superior and inferior head tilt. A superior head tilt produced a greater change in mesiodistal angulation than did an inferior head tilt. Accurately taken panoramic radiographs can serve as a convenient tool for evaluating the MDAI before, during and after orthodontic treatment. Additional radiographs are recommended for the mandibular anteriors.

  5. Positional changes of maxillary central incisors following orthodontic treatment using single-crown implants as fixed reference markers

    DEFF Research Database (Denmark)

    Brahem Ben, Elissa; Holm, Bente; Sonnesen, L

    2017-01-01

    . MATERIALS AND METHODS: Fifty-seven patients - thirty-seven with (test group) and twenty without pre-implant orthodontic treatment (control group) - were rehabilitated with 89 single-crown implants in the upper maxilla. Clinical and radiographic data, clinical photographs, and dental casts were collected......OBJECTIVES: This follow-up study (1) compares tooth displacement of central incisors in patients with and without pre-implant orthodontic treatment and (2) investigates whether sex, age, or orthodontic retention have an effect on tooth displacement after the insertion of single-crown implants...... during baseline examinations after prosthetic rehabilitation and at the final follow-up examination at least 5 years later. A total of 114 dental casts were digitalized and aligned using a software program to measure changes in the positions of the central incisors. RESULTS: After a follow-up period...

  6. Positional changes of maxillary central incisors following orthodontic treatment using single-crown implants as fixed reference markers.

    Science.gov (United States)

    Brahem, E B; Holm, B; Sonnesen, L; Worsaae, N; Gotfredsen, K

    2017-12-01

    This follow-up study (1) compares tooth displacement of central incisors in patients with and without pre-implant orthodontic treatment and (2) investigates whether sex, age, or orthodontic retention have an effect on tooth displacement after the insertion of single-crown implants. Fifty-seven patients - thirty-seven with (test group) and twenty without pre-implant orthodontic treatment (control group) - were rehabilitated with 89 single-crown implants in the upper maxilla. Clinical and radiographic data, clinical photographs, and dental casts were collected during baseline examinations after prosthetic rehabilitation and at the final follow-up examination at least 5 years later. A total of 114 dental casts were digitalized and aligned using a software program to measure changes in the positions of the central incisors. After a follow-up period of at least five years, 87% of the central incisors measured in the test group were displaced >0.25 mm vertically compared with 70% in the control group. Seventy-eight percent of the test group teeth had moved >0.25 mm horizontally compared with 55% in the control group. These differences were not significant, and there were no significant correlations with patient age or sex. The majority of patients had minor vertical (60%) or horizontal (67%) tooth displacement of the central incisors (0.25-0.75 mm) after a minimum follow-up period of 5 years. This study found no significant differences in tooth displacement comparing patients with and without pre-implant orthodontic treatment. No significant effect of sex, age, orthodontic retention, or implant location was observed on tooth displacement. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Experimental examination of the effects of televised motor vehicle commercials on risk-positive attitudes, emotions and risky driving inclinations.

    Science.gov (United States)

    Vingilis, Evelyn; Roseborough, James E W; Wiesenthal, David L; Vingilis-Jaremko, Larissa; Nuzzo, Valentina; Fischer, Peter; Mann, Robert E

    2015-02-01

    This study examined the short-term effects of risky driving motor vehicle television commercials on risk-positive attitudes, emotions and risky driving inclinations in video-simulated critical road traffic situations among males and females, within an experimental design. Participants were randomly assigned to one of three televised commercial advertising conditions embedded in a television show: a risky driving motor vehicle commercial condition, a non-risky driving motor vehicle commercial condition and a control non-motor vehicle commercial condition. Participants subsequently completed the Implicit Attitude Test (IAT) to measure risk-positive attitudes, Driver Thrill Seeking Scale (DTSS) to measure risk-positive emotions and the Vienna Risk-Taking Test - Traffic (WRBTV) to measure risky driving inclinations. ANOVA analyses indicated that type of commercial participants watched did not affect their performance on the IAT, DTSS or WRBTV. However, a main effect of heightened risk-positive emotions and risky driving inclinations was found for males. Despite public and governmental concern that risky driving motor vehicle commercials may increase the likelihood that people exposed to these commercials engage in risky driving, this experimental study found no immediate effect of brief exposure to a risky driving motor vehicle commercial on risk-positive attitudes, emotions or risky driving inclinations. Subsequent research should examine the effects of cumulative exposure to risky driving motor vehicle television commercials and print advertisements. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Barriers Inhibiting Inquiry-Based Science Teaching and Potential Solutions: Perceptions of Positively Inclined Early Adopters

    Science.gov (United States)

    Fitzgerald, Michael; Danaia, Lena; McKinnon, David H.

    2017-07-01

    In recent years, calls for the adoption of inquiry-based pedagogies in the science classroom have formed a part of the recommendations for large-scale high school science reforms. However, these pedagogies have been problematic to implement at scale. This research explores the perceptions of 34 positively inclined early-adopter teachers in relation to their implementation of inquiry-based pedagogies. The teachers were part of a large-scale Australian high school intervention project based around astronomy. In a series of semi-structured interviews, the teachers identified a number of common barriers that prevented them from implementing inquiry-based approaches. The most important barriers identified include the extreme time restrictions on all scales, the poverty of their common professional development experiences, their lack of good models and definitions for what inquiry-based teaching actually is, and the lack of good resources enabling the capacity for change. Implications for expectations of teachers and their professional learning during educational reform and curriculum change are discussed.

  9. The effect of inclined position on stone free rates in patients with lower caliceal stones during SWL session

    Directory of Open Access Journals (Sweden)

    Basri Cakiroglu

    2015-03-01

    Full Text Available Objective: To compare the outcomes of shock wave lithotripsy (SWL combined with inclined position and SWL alone in patients with lower pole calyx stones. Methods: Seven hundred forty patients who underwent SWL treatment for lower pole renal stones with a total diameter of 2 cm or less were prospectively randomized into two groups. They were comparable in terms of age, sex, and stone diameters. Patients with lower calyceal stones (4-20 mm were randomized to SWL (368 patients or SWL with simultaneous inclination (372 patients with 30o head down Trendelenburg position. Shock wave and session numbers were standardized according to stone size. Additional standardized shock waves were given to patients with stone fragments determined by kidney urinary bladder film and ultrasound at weeks 1, 4, 10. Results: The overall stone free rate (SFR was 73% (268/368 in patients with SWL alone and 81% (300/372 in SWL with inclination at the end of 12th week (p = 0.015. No significant adverse events were noted in both treatment groups. Conclusion: Simultaneous inclination of patients during SWL session increase SFR in lower caliceal stones significantly compared to SWL treatment alone.

  10. Where to position osteotomies in genioglossal advancement surgery based on locations of the mental foramen, canine, lateral incisor, central incisor, and genial tubercle.

    Science.gov (United States)

    Park, Joshua S; Lee, Christopher; Rogers, Jason M; Sun, Ho-Hyun; Liu, Yuan F; Elo, Jeffrey A; Inman, Jared C

    2017-09-01

    The study aimed to provide precise measurements of anterior mandibular structural anatomy and to explore potential osteotomies for genioglossal advancement. Cone beam computed tomography was used to analyze 33 randomly selected patients undergoing surgery for obstructive sleep apnea (OSA) between 2014 and 2016 at an academic surgical hospital. The locations of relevant mandibular structures were measured and statistical modeling was performed. Mean horizontal distances from midline to the mental foramina and the roots of the canine, lateral incisor, and central incisor were 22.11 ± 1.92, 13.56 ± 3.01, 6.19 ± 1.58, and 2.04 ± 0.87 mm, respectively. Mean vertical distances from the inferior border of the mandible were 15.15 ± 1.77, 17.11 ± 3.28, 20.48 ± 3.10, and 21.81 ± 3.49 mm, respectively. The superior border of the genial tubercle was 15.63 ± 2.75 mm, and the inferior border was 6.87 ± 3.29, from the inferior border of the mandible. The angle of decline of the best-fit line through the important structures was about 18° from the occlusion plane at the midline. A straight line estimating the mental foramen, canine, lateral incisor, and central incisor tooth roots crosses at a mean of 22.3-22.6 mm above the inferior border of the mandible at the midline and has an angle of decline of about 18°. Potential osteotomies made parallel to and below this line result in tradeoffs between maximizing capture of the genioglossus muscle attachment and risk of dental/neurovascular injury.

  11. Optical performance of inclined south-north axis three-positions tracked solar panels

    International Nuclear Information System (INIS)

    Zhong, Hao; Li, Guihua; Tang, Runsheng; Dong, Wenli

    2011-01-01

    In this work, the optical performance of solar panels with a new sun-tracking technique was theoretically investigated based on the proposed mathematical method and monthly horizontal radiation. The mechanism of the investigated sun-tracking is that the attitude angle of solar panels is daily adjusted three times at three fixed positions: eastward, southward, and westward in the morning, noon, and afternoon, respectively, by rotating solar panels about the inclined south-north axis (ISNA-3P sun-tracking). Calculation results showed that, for ISNA-3P tracked solar panels with a yearly fixed tilt-angle of the ISNA, the maximum annual collectible radiation on ISNA-3P tracked solar panels was about 93% of that on a solar panel with 2-axis sun-tracking; whereas for those with the ISNA being yearly adjusted four times at three fixed tilt-angles, it was about 96%. Results also indicated that the attempt to further increase the annual solar gain on ISNA-3P tracked solar panels by seasonally optimizing design of the sun-tracking system for maximizing solar gain in each of four seasons was not efficient, and thus not advisable in practical applications. Optimal parametric designs of such sun-tracking system for maximizing the annual solar gain on solar panels in different cases were also presented. -- Research highlights: → The paper presented a new sun-tracking technique (ISNA-3P) for possible applications in PV generating systems. → Algorithms to estimate daily collectible radiation on the fixed, 2-axis and ISNA-3P tracked solar panels were proposed based on solar geometry and monthly horizontal radiation. → A detailed theoretical study on the optical performance of such tracked solar panels in terms of R 3P-0 and R 3P-2 , the ratios of maximum annual solar gain to that on fixed and 2-axis tracked solar panels; optimal parameters affecting the optical performance of the systems were presented in the different cases. → Results showed that such sun-tracking system

  12. Twin Block appliance with acrylic capping does not have a significant inhibitory effect on lower incisor proclination

    NARCIS (Netherlands)

    van der Plas, Mark Cornelis; Janssen, Krista Ingeborg; Pandis, Nikolaos; Livas, Christos

    Objective: To investigate the effect of acrylic capping, treatment duration, overjet, and lower incisor inclination on the posttreatment tooth position in patients treated with 2 Twin Block (TB) appliance versions. Materials and Methods: Cephalograms of 56 patients with Class II malocclusion (21

  13. Análise da correlação entre a angulação (mesiodistal dos caninos e a inclinação (vestibulolingual dos incisivos Analysis of the correlation between mesiodistal angulation of canines and labiolingual inclination of incisors

    Directory of Open Access Journals (Sweden)

    Amanda Sayuri Cardoso Ohashi

    2011-06-01

    Full Text Available OBJETIVO: avaliar o nível de correlação entre a angulação dos caninos e a inclinação dos incisivos. MÉTODOS: a angulação mesiodistal dos caninos e a inclinação vestibulolingual dos incisivos foram obtidas em um programa digital gráfico (Imagetool®, a partir de fotografias padronizadas dos modelos de 60 pacientes. A inclinação dos incisivos foi, ainda, avaliada pela cefalometria lateral. RESULTADOS: o erro casual mostrou uma variação em torno de 2° nas medidas feitas nos modelos (1,8-2,5º, enquanto o erro sistemático, avaliado pela teste de correlação intraclasse, revelou uma excelente reprodutibilidade para ambos os métodos empregados (p0,05 e variou bastante na arcada inferior (r=0,14-0,50, dependendo da grandeza correlacionada. CONCLUSÃO: ratifica-se a introdução de mudanças na angulação dos caninos com o intuito de acompanhar as compensações observadas na inclinação dos incisivos, principalmente na arcada inferior.OBJECTIVE: To assess the degree of correlation between canine angulation and incisor inclination. METHODS: Mesiodistal angulation of canines and labiolingual inclination of incisors were obtained by means of digital graphics software (ImageTool® from standardized photographs of the casts of 60 patients. Incisor inclination was also assessed by lateral cephalometric radiographs. RESULTS: Random error showed a variation of around 2° in measurements made on the casts (1.8-2.5, while systematic error, measured by the intraclass correlation test, displayed excellent reproducibility for both methods used in this study (p0.05 and varied widely in the mandibular arch (r=0.14 to 0.50. CONCLUSIONS: The introduction of changes in the angulation of canines with the aim of monitoring compensations observed in incisor inclination is warranted, especially in the lower arch.

  14. If Science Teachers Are Positively Inclined Toward Inclusive Education, Why Is It So Difficult?

    Science.gov (United States)

    Spektor-Levy, Ornit; Yifrach, Merav

    2017-08-01

    This paper describes the unique challenges that students with learning disabilities (LD) experience in science studies and addresses the question of the extent to which science teachers are willing and prepared to teach in inclusive classrooms. We employed the theory of planned behavior (TPB), according to which behavioral intentions are a function of individuals' attitudes toward the behavior, their subjective norms, and their perceived control—i.e., their perception of the simplicity and benefits of performing the behavior. The study comprised 215 junior high school science teachers, who answered a TPB-based quantitative questionnaire. Semi-structured interviews were conducted to support and enrich the findings and conclusions. We found that teachers held positive attitudes and were willing to adapt their teaching methods (perceived control), which correlated and contributed to their behavioral intention. In terms of subjective norms, however, they felt a lack of support and ongoing guidance in providing the appropriate pedagogy to meet the needs of students with LD. We therefore recommend that educational policy makers and school management devote attention and resources to providing professional training and appropriate instructional materials and to establishing frameworks for meaningful cooperation between the science teachers and special education staff. This could ensure the efficient cooperation and coordination of all the involved parties and send a positive message of support to the science teachers who are the actual implementers of change.

  15. The kinematic relationship between sitting and standing posture and pelvic inclination and its significance to cup positioning in total hip arthroplasty.

    Science.gov (United States)

    Stephens, Andrew; Munir, Selin; Shah, Siddarth; Walter, William Lindsay

    2015-03-01

    The aim of this study is to describe the influence of sitting and standing posture on sagittal pelvic inclination in total hip replacement patients to assist with correct acetabular component positioning. Lateral radiographs of the pelvis and lumbar spine in sitting and standing positions were extracted. Pelvic tilt was measured using the vertical inclination of a line from the anterior superior iliac spine (ASIS) to pubic tubercle. Sacral inclination, Cobb angle of the lumbar spine and hip flexion were recorded. Sixty patients were identified with a mean age of 63. Men were more likely to flex the lumbar spine in sitting (p = 0.004); 80° of hip flexion is required for seated posture. Stiff hips required compensatory pelvic flexion and lumbar flexion in sitting. There is a linear relationship between hip flexion and pelvic tilt, hip flexion and lumbar lordosis. Pelvic orientation is determined by lumbar and hip stiffness. This impacts on acetabular version.

  16. Maxillary incisor retraction: evaluation of different mechanisms

    Directory of Open Access Journals (Sweden)

    Antônio Carlos de Oliveira Ruellas

    2013-04-01

    Full Text Available OBJECTIVE: To mechanically evaluate different systems used for incisors retraction. METHODS: Three different methods for incisors retraction using 0.019 x 0.025-in stainless steel wire were evaluated. The samples were divided into three groups: Group A (retraction arch with 7-mm high vertical hooks; Group G3 (elastic chain attached to the miniimplant and to the 3-mm stainless steel hook soldered to the retraction arch; Group G6 (elastic chain attached to the mini-implant and to the 6-mm stainless steel hook soldered to the retraction arch. A dental mannequin was used for evaluation in order to simulate the desired movements when the device was exposed to a heat source. The analysis of variance (ANOVA and the Tukey test were used (p < 0.05. RESULTS: The results demonstrated that Groups G3 and G6 exhibited less extrusion and less incisor inclination during the retraction phase (p < 0.05. With regard to incisor extrusion, statistically significant differences were observed between Groups A and G3, and between Groups A and G6 (p < 0.05. Regarding incisor inclination, statistically significant differences were observed between the three systems evaluated (p < 0.05. CONCLUSIONS: Arches with 6-mm vertical hooks allow the force to be applied on the center of resistance of the incisors, thus improving mechanical control when compared with the other two systems.

  17. Inclined planes

    CERN Document Server

    Rivera, Andrea

    2016-01-01

    From moving ramps to playground slides, inclined planes are at work all over in our world today. Learn all about them in five easy-to-read chapters. Vibrant, full-color photos, bolded glossary words, and a key stats section let readers zoom in even deeper. Aligned to Common Core Standards and correlated to state standards. Abdo Zoom is a division of ABDO.

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

    DEFF Research Database (Denmark)

    Peng, Min; Fei, Wei; Hosseini, Mandana

    2013-01-01

    The aims of the present study were to evaluate the influence of implant position on clinical crown length and marginal soft tissue dimensions at implant-supported single crowns of maxillary central incisors, and to validate the papilla index score (PIS). Twenty-five patients, who had lost one...... as controls. Paired sample t-testand Pearson´s correlation analysis were used to analyze implant position, dimension of crownand papilla fill.Cohen’s ¿ andSpearman correlation were used to validate the PIS.The implant-supported crown was statistically longer than the contra-lateral tooth......, and there was significant correlation between the oro-facial position of the implant and the crown length difference (r=.607, p=.001). The distalpapilla was significantly shorter than the mesialpapilla at implant-supported crowns (ptooth (p=.415...

  19. [Incisor repositioning: a new approach in orthodontics].

    Science.gov (United States)

    Dallel, Ines; Khemiri, Mourad; Fathallah, Safa; Ben Rejeb, Salwa; Tobji, Samir; Ben Amor, Adel

    2015-12-01

    Lower incisors axis has a "key" position in different cephalometric analysis. However, several critics are directed towards the cephalometric profile and cephalometric landmarks (point, line and angle). The published norms and the cephalometric standards recommended for the optimal positioning of incisors could only be used as general clinical guidelines. Incisor repositioning to achieve optimal facial aesthetics requires taking into consideration the hard and soft tissues of the face, the profile, the muscular dynamics as well as the facial growth. In this work, we propose a new approach of incisor repositioning taking into account the variability of periodontal, functional and aesthetic factors. © EDP Sciences, SFODF, 2015.

  20. Optimal parameters for final position of teeth in space closure in case of a missing upper lateral incisor.

    Science.gov (United States)

    Lombardo, Luca; D'Ercole, Antonio; Latini, Michele Carmelo; Siciliani, Giuseppe

    2014-11-27

    The aim of this study was to provide clinical indications for the correct management of appliances in space closure treatment of patients with agenesis of the upper lateral incisors. Virtual setup for space closure was performed in 30 patients with upper lateral incisor agenesis. Tip, torque and in-out values were measured and compared with those of previous authors. In the upper dentition, the tip values were comparable to those described by Andrews (Am J Orthod 62(3):296-309, 1972), except for at the first premolars, which require a greater tip, and the first molars, a lesser tip. The torque values showed no differences except for at the canines, where it was greater, and the in-out values were between those reported by Andrews and those by Watanabe et al. (The Shikwa Gakuho 96:209-222, 1996) (except for U3 and U4). The following prescriptions are advisable: tip 5°, torque 8° and in-out 2.5 for U1; tip 9°, torque 3° and in-out 3.25 for U3; tip 10°, torque -8° and in-out 3.75 for U4; and tip 5°, torque -8° and in-out 4 for U5. Andrews' prescription is suitable for the lower jaw, except for at L6. It is also advisable to execute selective grinding (1.33±0.5 mm) and extrusion (0.68±0.23 mm) on the upper canine during treatment, and the first premolar requires some intrusion (0.56±0.30 mm).

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

    DEFF Research Database (Denmark)

    Kjaer, I; Balslev-Olesen, M

    2012-01-01

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

  2. Macrodontic maxillary incisor in alagille syndrome

    Directory of Open Access Journals (Sweden)

    Mauro Cozzani

    2012-01-01

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

  3. Simplification of rat intubation on inclined metal plate.

    Science.gov (United States)

    Kastl, Sigrid; Kotschenreuther, U; Hille, B; Schmidt, J; Gepp, H; Hohenberger, W

    2004-12-01

    Small-animal intubation is often necessary during inhalation anesthesia to allow steady-state conditions for large operations and in vivo experiments in all fields of experimental surgery. In rats, placing an orotracheal tube is technically difficult primarily because of the small size of the subject and the lack of equipment specifically designed for this task. We describe a simple rat intubation technique in which the animal is suspended in dorsal recumbency on an inclined metal plate. The animal, anesthetized with ether, is fixed to a 70 degrees-inclined metal plate in a dorsal position by means of a Mersilene ribbon hooked around the upper incisors. This method of positioning the animal is the most important step in the intubation process and further facilitates the technique already described by other authors. A human otoscope was used as a laryngoscope, intubation was performed using the Seldinger technique, and a 14-gauge intravenous catheter served as an endotracheal tube. This inexpensive technique is quickly learned and can be used in any laboratory. Safe and reliable airway management can thus be achieved, permitting in vivo examinations and operations.

  4. Concomitant hypohyperdontia: simultaneous occurrence of a mesiodens and agenesis of a maxillary lateral incisor.

    Science.gov (United States)

    Segura, J J; Jiménez-Rubio, A

    1998-10-01

    A 13-year-old boy appeared for evaluation with a missing maxillary left lateral incisor. He also had an abnormally shaped tooth in the midline between his maxillary central incisors. This mesiodens had an incompletely developed root. The unusual association of these 2 anomalies is discussed as a possible transposition of the lateral incisor to the mesiodens position.

  5. The effects of impacted premaxillary supernumerary teeth on permanent incisors.

    Science.gov (United States)

    Jung, Yun-Hoa; Kim, Ji-Yeon; Cho, Bong-Hae

    2016-12-01

    The aim of this study was to examine the radiographic features associated with impacted premaxillary supernumerary teeth, to determine the relationship between their characteristics and their effects on permanent incisors, and to investigate the types of orthodontic treatment that patients received after the extraction of impacted supernumerary teeth. The clinical records and radiographs of 193 patients whose impacted premaxillary supernumerary teeth were removed were retrospectively reviewed, and 241 impacted supernumerary teeth were examined. Cone-beam computed tomographic images and panoramic radiographs were examined to determine the number, location, sagittal position, orientation, and morphology of the supernumerary teeth. Their effects on permanent incisors and the orthodontic treatment received by patients after the extraction of the supernumeraries were also investigated. Supernumerary teeth were most frequently observed in the central incisor region, in the palatal position, in the inverted orientation, and were most commonly conical in shape. The most common complication was median diastema, followed by displacement and delayed eruption of the adjacent incisors. Ten (71.4%) of the 14 odontomas showed delayed eruption of the adjacent incisors. Displacement of the incisors was more frequently observed in association with supernumerary teeth with tuberculate or supplemental shapes. Orthodontic traction was most frequently performed after the removal of odontomas. In 32 cases (13.3%), permanent incisors erupted after the orthodontic creation of sufficient space. Median diastema was most common complication. The delayed eruption of incisors was common in supernumerary teeth with a vertical orientation and an odontoma shape.

  6. The effects of impacted premaxillary supernumerary teeth on permanent incisors

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yun Hoa; Kim, Ji Yeon; Cho, Bong Hae [School of Dentistry, Pusan National University, Yangsan (Korea, Republic of)

    2016-12-15

    The aim of this study was to examine the radiographic features associated with impacted premaxillary supernumerary teeth, to determine the relationship between their characteristics and their effects on permanent incisors, and to investigate the types of orthodontic treatment that patients received after the extraction of impacted supernumerary teeth. The clinical records and radiographs of 193 patients whose impacted premaxillary supernumerary teeth were removed were retrospectively reviewed, and 241 impacted supernumerary teeth were examined. Cone-beam computed tomographic images and panoramic radiographs were examined to determine the number, location, sagittal position, orientation, and morphology of the supernumerary teeth. Their effects on permanent incisors and the orthodontic treatment received by patients after the extraction of the supernumeraries were also investigated. Supernumerary teeth were most frequently observed in the central incisor region, in the palatal position, in the inverted orientation, and were most commonly conical in shape. The most common complication was median diastema, followed by displacement and delayed eruption of the adjacent incisors. Ten (71.4%) of the 14 odontomas showed delayed eruption of the adjacent incisors. Displacement of the incisors was more frequently observed in association with supernumerary teeth with tuberculate or supplemental shapes. Orthodontic traction was most frequently performed after the removal of odontomas. In 32 cases (13.3%), permanent incisors erupted after the orthodontic creation of sufficient space. Median diastema was most common complication. The delayed eruption of incisors was common in supernumerary teeth with a vertical orientation and an odontoma shape.

  7. The effects of impacted premaxillary supernumerary teeth on permanent incisors

    International Nuclear Information System (INIS)

    Jung, Yun Hoa; Kim, Ji Yeon; Cho, Bong Hae

    2016-01-01

    The aim of this study was to examine the radiographic features associated with impacted premaxillary supernumerary teeth, to determine the relationship between their characteristics and their effects on permanent incisors, and to investigate the types of orthodontic treatment that patients received after the extraction of impacted supernumerary teeth. The clinical records and radiographs of 193 patients whose impacted premaxillary supernumerary teeth were removed were retrospectively reviewed, and 241 impacted supernumerary teeth were examined. Cone-beam computed tomographic images and panoramic radiographs were examined to determine the number, location, sagittal position, orientation, and morphology of the supernumerary teeth. Their effects on permanent incisors and the orthodontic treatment received by patients after the extraction of the supernumeraries were also investigated. Supernumerary teeth were most frequently observed in the central incisor region, in the palatal position, in the inverted orientation, and were most commonly conical in shape. The most common complication was median diastema, followed by displacement and delayed eruption of the adjacent incisors. Ten (71.4%) of the 14 odontomas showed delayed eruption of the adjacent incisors. Displacement of the incisors was more frequently observed in association with supernumerary teeth with tuberculate or supplemental shapes. Orthodontic traction was most frequently performed after the removal of odontomas. In 32 cases (13.3%), permanent incisors erupted after the orthodontic creation of sufficient space. Median diastema was most common complication. The delayed eruption of incisors was common in supernumerary teeth with a vertical orientation and an odontoma shape

  8. Chair time saving method for treatment of an impacted maxillary central incisor with 15-month follow-up

    Directory of Open Access Journals (Sweden)

    Saeed Noorollahian

    2018-01-01

    Full Text Available Maxillary permanent incisors have a major role in facial esthetics. Impaction of them has great adverse effect on smile and causes serious concerns in patient and parents. Physical barriers (e.g., overretained primary teeth, supernumerary teeth, and pathologic lesions, space problems, developmental abnormalities, altered eruption sequence, trauma, palatal clefts, and genetics can act as etiologic factors. Currently, the conventional technique to treatment of impacted teeth consists of a combined orthodontic and surgical approach, to guide the impacted teeth in a constant position and surrounded by normal hard and soft tissues. Treatment is challenging because of some limitations such as patient's age, cooperation, anchorage, and mechanotherapy possibilities. Hence, sophisticated treatment planning is crucial. A 9-year-old girl with horizontally impacted maxillary left central incisor treated with surgical exposure and closed orthodontic forced eruption with 2 × 4 partial setup fixed appliances. Force was applied with 0.014 inch nickel–titanium wire as elastic overlay and handmade ligated bracket. To save chair time in each appointment, the overlay was activated by twisting of ligature wire extensions around it. After 16-month treatment, impacted incisor emerged in oral cavity, with accepted alignment and inclination. Handmade ligated bracket with ligature wire extensions is useful for the treatment of impacted teeth. Due to easy activation of overlay in this method, chair time become short in each appointment.

  9. Measurement of defects on the wall by use of the inclination angle of laser slit beam and position tracking algorithm of camera

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Hwan; Yoon, Ji Sup; Jung, Jae Hoo; Hong, Dong Hee; Park, Gee Yong

    2001-01-01

    In this paper, a method of measuring the size of defects on the wall and restructuring the defect image is proposed based on the estimation algorithm of a camera orientation which uses the declination angle of the line slit beam. To reconstruct the image, an algorithm of estimating the horizontally inclined angle of CCD camera is presented. This algorithm adopts a 3-dimensional coordinate transformation of the image plane where both the LASER beam and the original image of the defects exist. The estimation equation is obtained by using the information of the beam projected on the wall and the parameters of this equation are experimentally obtained. With this algorithm, the original image of the defect can be reconstructed into the image which is obtained by a camera normal to the wall. From the result of a series of experiment shows that the measuring accuracy of the defect is within 0.5% error bound of real defect size under 30 degree of the horizontally inclined angle. Also, the accuracy is deteriorates with the error rate of 1% for every 10 degree increase of the horizontally inclined angle. The estimation error increases in the range of 30{approx}50 degree due to the existence of dead zone of defect depth, and defect length can not be measured due to the disappearance of image data above 70 degree. In case of under water condition, the measuring accuracy is also influenced due to the changed field of view of both the camera and the laser slit beam caused by the refraction rate in the water. The proposed algorithm provides the method of reconstructing the image taken at any arbitrary camera orientation into the image which is obtained by a camera normal to the wall and thus it enables the accurate measurement of the defect lengths only by using a single camera and a laser slit beam.

  10. Vehicle with inclinable caterpillars

    International Nuclear Information System (INIS)

    Carra, O.; Delevallee, A.

    1991-01-01

    Vehicle has a body with propulsion assemblies that drive caterpillar tracks. When a propulsion unit inclines about its articulation axis it is aided by an advance movement of the caterpillar track in the opposite direction of rotation [fr

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

    Directory of Open Access Journals (Sweden)

    Zohreh Hedayati

    2014-01-01

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

  12. Impact on perceived root resorption based on the amount of incisal inclination as determined from conventional panoramic radiography.

    Science.gov (United States)

    Tieu, Long Dao; Normando, David; Toogood, Roger; Flores-Mir, Carlos

    2015-10-01

    Our objective was to measure the impact on perceived root resorption based on the amount of anteroposterior incisal inclination as determined in vitro from conventional panoramic radiography. A rapid prototyping model was created to mimic different maxillary and mandibular incisal anteroposterior inclinations. Two titanium beads were placed on the incisors at the apical and incisal edges. Panoramic radiographs were obtained, with the incisors changing relative inclination by 10° increments. The length was measured from the midpoint of the bead on the incisal edge to the midpoint of the bead on the apical edge. By using a length of wire of known size, this value was compared in all images to correct for image magnification. Changes to mandibular incisor anteroposterior inclinations, as either a theoretical proclination or retroclination, resulted in an increase of "apparent" root resorption on a panoramic radiograph. When the maxillary incisors were significantly and severely retroclined, they appeared larger than expected. When the maxillary incisors were mildly retroclined, the length was roughly similar to the theoretical model. When the maxillary incisors were mildly proclined, they appeared shorter than expected. The foreshortening or forelengthening of incisor root lengths because of incisor inclination vs root resorption cannot be reliably evaluated from panoramic images. The proposed theoretical model helps to understand the direction of the changes produced by the magnification factor. More severe scenarios where either the maxillary or the mandibular teeth are outside the focal trough have not been fully evaluated. The clinical impact of these changes is likely to be questionable. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Mahesh Jain

    2014-01-01

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

  14. [Light reflection zone on the incisors' surface--a new parameter for smile esthetics evaluation].

    Science.gov (United States)

    Brezniak, N; Wasserstein, A; Shmuli, T

    2012-07-01

    The light reflection zone (LRZ) is a bright white dot or area that appears on the surface of the maxillary central incisors and/or the gingiva of the front teeth, visible in intra-oral and smile extra-oral photographs. Previously, a positive correlation between the location of the LRZ as observed in intra-oral frontal photographs and the inclination of the upper central incisors as measured on lateral headfims was found. The purpose of this study was to find whether this LRZ location can serve as a new parameter influencing the level of smile esthetics. Twelve pairs of facial photographs, including 10 of ordinary smiling persons and 2 of smiling models, were presented to 138 participants. The only difference between each pair was the location of the LRZ that was moved, compared to the original photograph, gingivally or incisally respectively, using Photoshop (Adobe). Each participant was asked to mark whether he/she noticed a difference between the 2 pictures, and if so, to score the nicer smile. Data analysis was carried out using Chi square test and Fisher's exact test (SPSS v17). The results showed that most of the participants did not recognize the differences between the pairs however, when differences were recognized, most of the participants pointed on the smile where the LRZ was located gingivally as the nicer one. This result was with statistical significance for the 2 models (p < 0.05), In conclusion, the LRZ is a new, yet unrecognized, parameter that can serve as a tool for the diagnosis of esthetic smile. The general population defines a nicer smile when the LRZ is located in the gingival area of the upper central incisors' surface rather than the incisal third. The LRZ should probably be studied not only in Orthodontics but also in other branches of dentistry.

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

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2015-10-01

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

  16. Molar Incisor Hypomineralization.

    Science.gov (United States)

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

    2016-07-01

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

  17. ["Molar-incisor hypomineralization"].

    Science.gov (United States)

    Kellerhoff, Nadja-Marina; Lussi, Adrian

    2004-01-01

    Hypocalcification of the enamel is the most common developmental disorder observed in teeth. The prevalence of this kind of hypomineralisation is about 10-19%. These molars are often referred to as cheese molars, because the lesions clinically resemble cheese in color and consistency. Other descriptions are: idiopathic enamel hypomineralisation in the permanent first molars, idiopathic enamel opacities in the permanent first molars, non fluoride enamel hypomineralisation in the permanent first molars, non-endemic mottling of enamel in the permanent first molars. Molar-Incisor Hypomineralisation is today the proposed expression for this disease. Occlusal surfaces of the first permanent molar are most commonly affected. The lesions are more frequent in the upper jaw than in the lower jaw. The incisors are affected to a lesser degree than the molars. Several aetiological factors can cause these defects. Some studies show a relation between intake of dioxins via mother's milk after prolonged breast feeding and developmental defects of the child's teeth. Because the ameloblasts are very sensitive to oxygen supply, complications involving oxygen shortages during birth or respiratory diseases such as asthma or bronchitis and pneumonia are discussed as further aetiological factors. Renal insufficiency, hypoparothyroidism, diarrhoea, malabsorption and malnutrition and high-fever diseases can be other reasons for the occurrence of these defects. Defective enamel can be a locus of lowered resistance for caries. Histologically there are areas of porosity of varying degrees. The affected teeth can be very sensitive to air, cold, warm and mechanical stimuli. Toothbrushing may create toothache in these teeth. We therefore suggest that these patients receive intensified prevention with fluoride varnish, a fissure sealing, GIZ, composits, stainless steel crowns or implants. In some cases an interdisciplinary approach with an orthodontist can result in the extraction of the molars

  18. Post-traumatic impaction of maxillary incisors: diagnosis and treatment.

    Science.gov (United States)

    Paoloni, Valeria; Pavoni, Chiara; Mucedero, Manuela; Bollero, Patrizio; Laganà, Giuseppina; Cozza, Paola

    2013-01-01

    To provide clinicians with useful information for immediate diagnosis and management of impacted maxillary incisors due to trauma. We present a case of post-traumatic impaction of a central right maxillary incisor in a young patient. The treatment plan consisted in the interceptive management (surgical and orthodontic), the valuation of the necessary space to move the impacted tooth in the normal position and the biomechanical approach for anchorage, avoiding prosthetic/implants replacement. THE THERAPY OF AN IMPACTED MAXILLARY INCISOR DUE TO TRAUMA REQUIRES A MULTIDISCIPLINARY APPROACH: orthodontic, surgical, endodontic and periodontal considerations are essential for successful treatment. SURGICAL EXPOSURE AND ORTHODONTIC TRACTION IS THE TREATMENT MOST OFTEN USED IN CASE OF POSTTRAUMATIC IMPACTED INCISOR: this technique in fact can lead to suitable results at the periodontal, occlusal and esthetics levels at an early stage and more definitively than with other treatment options.

  19. Orthodontic management of unfavorably impacted maxillary central incisor (sickle incisor

    Directory of Open Access Journals (Sweden)

    Abhisek Ghosh

    2014-01-01

    Full Text Available Impaction is an eruptive disturbance characterized by the inability of the teeth to reach from its place of formation to the place of its function. Maxillary central incisor impactions are usually rare as it is one of the first permanent teeth to erupt in the oral cavity. The etiologic factors include the presence of mesiodens, dilacerations of roots, odontomas, fibrous gingiva etc. Impaction of central incisor usually poses a functional as well as an esthetic problem. Treatment options might include surgical intervention or prosthetic rehabilitation, but the best modality would be its orthodontic management. Orthodontic disimpaction in such situations provides a solution to an otherwise long-term esthetic and functional problem. This case report provides a detailed descriptive overview on the orthodontic management of an unfavorably impacted maxillary central incisor (sickle incisor.

  20. A randomized clinical trial comparing mandibular incisor proclination produced by fixed labial appliances and clear aligners.

    Science.gov (United States)

    Hennessy, Joe; Garvey, Thérèse; Al-Awadhi, Ebrahim A

    2016-09-01

    To compare the mandibular incisor proclination produced by fixed labial appliances and third generation clear aligners. Patients underwent a course of orthodontic treatment using either fixed labial appliances or clear aligners (Invisalign). Mandibular incisor proclination was measured by comparing pretreatment and near-end treatment lateral cephalograms. Eligibility criteria included adult patients with mild mandibular incisor crowding (clear aligner group. Baseline characteristics were similar for both groups: Fixed appliance mean crowding was 2.1 ± 1.3 mm vs clear aligner mean crowding, 2.5 ± 1.3 mm; pretreatment mean mandibular incisor inclination for the fixed appliance group was 90.8 ± 5.4° vs 91.6 ± 6.4° for the clear aligner group. Fixed appliances produced 5.3 ± 4.3° of mandibular incisor proclination. Clear aligners proclined the mandibular incisors by 3.4 ± 3.2°. The difference between the two groups was not statistically significant (P > .05). There was no difference in the amount of mandibular incisor proclination produced by clear aligners and fixed labial appliances in mild crowding cases.

  1. The rat incisor in toxicologic pathology

    NARCIS (Netherlands)

    Kuijpers, M.H.M.; Kooij, A.J. van de; Slootweg, P.J.

    1996-01-01

    Microscopic examination of the incisors of rats and mice may reveal toxicologically significant changes. First, the incisor morphology reflects the nutritional status of the animal: fluctuations of mineral metabolism and vitamin availability are disclosed by the rodent incisors, because the incisors

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

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

    2015-01-01

    Introduction:Cleft lip and palate are craniofacial anomalies highly prevalent in the overall population. In oral clefts involving the alveolar ridge, variations of number, shape, size and position are observed in maxillary lateral incisors. The objective of this manuscript is to elucidate the embryonic origin of maxillary lateral incisors in order to understand the etiology of these variations.Contextualization: The hypothesis that orofacial clefts would split maxillary lateral incisor buds h...

  4. Six upper incisors: what's next?

    Science.gov (United States)

    Berneburg, Mirjam; Meller, Christian

    2016-01-01

    This case report describes our therapeutic approach taken in a girl with eruption disturbance of the upper anterior teeth. Two supernumerary teeth were involved, which required a combination of orthodontic and surgical treatment. The initial situation in the upper anterior segment was characterized by two supernumerary mesial incisors, ectopic eruption of the distally located lateral incisors, and crowded tooth buds in the canine areas. Key decisions had to be made as to whether any teeth needed to be extracted and, if so, regarding the timing and sites of extraction. Removing teeth too early would have preempted a complete assessment of tooth quality, whereas late extraction would have carried a risk of eruption disturbance. Once the distal lateral incisors had erupted, the supernumerary mesial incisors were extracted and the central incisors (initially located in between) mesialized with a bracket appliance. Following space closure and mesialization of the lateral incisors, a functional appliance was used. Tooth 13 was erupting, while tooth 23 was displaced and subsequently aligned as part of the final bracket treatment. To successfully treat eruption disturbances, a careful diagnostic workup is essential, including informative radiographs, personalized treatment planning, and correct decision-making as to whether teeth need to be extracted and regarding the timing and sites of extraction. Finally, the eruption of the canines should be monitored.

  5. Evaporation of inclined water droplets

    Science.gov (United States)

    Kim, Jin Young; Hwang, In Gyu; Weon, Byung Mook

    2017-01-01

    When a drop is placed on a flat substrate tilted at an inclined angle, it can be deformed by gravity and its initial contact angle divides into front and rear contact angles by inclination. Here we study on evaporation dynamics of a pure water droplet on a flat solid substrate by controlling substrate inclination and measuring mass and volume changes of an evaporating droplet with time. We find that complete evaporation time of an inclined droplet becomes longer as gravitational influence by inclination becomes stronger. The gravity itself does not change the evaporation dynamics directly, whereas the gravity-induced droplet deformation increases the difference between front and rear angles, which quickens the onset of depinning and consequently reduces the contact radius. This result makes the evaporation rate of an inclined droplet to be slow. This finding would be important to improve understanding on evaporation dynamics of inclined droplets. PMID:28205642

  6. Bidispersive-inclined convection

    Science.gov (United States)

    Mulone, Giuseppe; Straughan, Brian

    2016-01-01

    A model is presented for thermal convection in an inclined layer of porous material when the medium has a bidispersive structure. Thus, there are the usual macropores which are full of a fluid, but there are also a system of micropores full of the same fluid. The model we employ is a modification of the one proposed by Nield & Kuznetsov (2006 Int. J. Heat Mass Transf. 49, 3068–3074. (doi:10.1016/j.ijheatmasstransfer.2006.02.008)), although we consider a single temperature field only. PMID:27616934

  7. Effect of implant position, angulation, and attachment height on peri-implant bone stress associated with mandibular two-implant overdentures: a finite element analysis.

    Science.gov (United States)

    Hong, Hae Ryong; Pae, Ahran; Kim, Yooseok; Paek, Janghyun; Kim, Hyeong-Seob; Kwon, Kung-Rock

    2012-01-01

    The aim of this study was to analyze and compare the level and distribution of peri-implant bone stresses associated with mandibular two-implant overdentures with different implant positions. Mathematical models of mandibles and overdentures were designed using finite element analysis software. Two intraosseous implants and ball attachment systems were placed in the interforaminal region. The overdenture, which was supported by the two implants, was designed to withstand bilateral and unilateral vertical masticatory loads (total 100 N). In all, eight types of models, which differed according to assigned implant positions, height of attachments, and angulation, were tested: MI (model with implants positioned in the lateral incisor sites), MC (implants in canine sites), MP (implants in premolar sites), MI-Hi (greater height of attachments), MC-M (canine implants placed with mesial inclination), MC-D (canine implants placed with distal inclination), MC-B (canine implants placed with buccal inclination), and MC-L (canine implants placed with lingual inclination). Peri-implant bone stress levels associated with overdentures retained by lateral incisor implants resulted in the lowest stress levels and the highest efficiency in distributing peri-implant stress. MI-Hi showed increased stress levels and decreased efficiency in stress distribution. As the implants were inclined, stress levels increased and the efficiency of stress distribution decreased. Among the inclined models, MC-B showed the lowest stress level and best efficiency in stress distribution. The lowest stress and the best stability of implants in mandibular two-implant overdentures were obtained when implants were inserted in lateral incisor areas with shorter attachments and were placed parallel to the long axes of the teeth.

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

    Directory of Open Access Journals (Sweden)

    Guilherme dos Santos Trento

    2015-12-01

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

  9. Cone Beam Computed Tomography-based Evaluation of the Anterior Teeth Position Changes obtained by Passive Self-ligating Brackets.

    Science.gov (United States)

    Rhoden, Fernando K; Maltagliati, Liliana Á; de Castro Ferreira Conti, Ana C; Almeida-Pedrin, Renata R; Filho, Leopoldino C; de Almeida Cardoso, Maurício

    2016-08-01

    The objective of this study was to evaluate the anterior teeth position changes obtained by passive self-ligating brackets using cone beam computed tomography (CBCT). Twenty patients with a mean age of 16.5 years, class I malocclusion, constricted maxillary arch, and teeth crowding above 5 mm were enrolled in this study, and treated by passive orthodontic self-ligating brackets. A sequence of stainless steel thermoset wire was implemented with ending wire of 0.019" × 0.025". The CBCT and dental casts were obtained prior to the installation of orthodontic appliances (T1), and 30 days after rectangular steel wire 0.019" × 0.025" installation (T2). The measurements in CBCT were performed with the Anatomage software, and the dental casts were evaluated with a digital caliper rule with an accuracy of 0.01 mm. The CBCT data demonstrated mean buccal inclination of the upper and lower central incisors ranging from 6.55° to 7.24° respectively. The upper and lower lateral incisors ranged from 4.90° to 8.72° respectively. The lower canines showed an average increase of 3.88° in the buccal inclination and 1.96 mm in the transverse intercuspal distance. The upper canines showed a negative inclination with mean average of -0.36°, and an average increase of 0.82 mm in the transverse distance, with negative correlation with the initial crowding. Treatment with passive self-ligating brackets without obtaining spaces increases buccal inclination of the upper and lower incisors with no correlation with the amount of initial teeth crowding. The intercanine distance tends to a small increase showing different inclinations between the arches. When taking into account the self-ligating brackets, the amount of initial dental crowding is not a limitation factor that could increase the buccal inclination of the anterior teeth.

  10. The radiographic localization of unerupted maxillary incisors and supernumeraries

    International Nuclear Information System (INIS)

    Kim, Jae Duk; Lee, Chang Yul; You, Choong Hyun

    2003-01-01

    To evaluate the use of the vertical tube shift from a panoramic film and a periapical film to localize unerupted maxillary incisors and supernumeraries. The total of 103 displaced maxillary incisors or embedded supernumeraries were examined in this study. The vertical tube shift technique with panoramic and periapical radiography by normal projection taken and compared to localize the position of the embedded maxillary incisors or supernumeraries by a radiologist and 5 general dentists. The gold standard used for the radiographic comparisons was the true position of the embedded tooth as confirmed by horizontal tube shift technique using three periapical radiographs. The general dentist examiners were instructed on the use of the modified acronym 'SLDOBU' by the radiologist as it pertains to panoramic radiographs as the principle of vertical tube shift. All of the embedded maxillary incisors and supernumeraries were successfully located using the vertical tube shift from a panoramic and a maxillary anterior periapical radiograph by the radiologist and 5 general dentists. The use of a panoramic film with a periapical film combination for a vertical tube shift can be useful to localize unerupted maxillary incisors and supernumeraries.

  11. The radiographic localization of unerupted maxillary incisors and supernumeraries

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Duk; Lee, Chang Yul; You, Choong Hyun [Chosun University College of Medicine, Kwangju (Korea, Republic of)

    2003-12-15

    To evaluate the use of the vertical tube shift from a panoramic film and a periapical film to localize unerupted maxillary incisors and supernumeraries. The total of 103 displaced maxillary incisors or embedded supernumeraries were examined in this study. The vertical tube shift technique with panoramic and periapical radiography by normal projection taken and compared to localize the position of the embedded maxillary incisors or supernumeraries by a radiologist and 5 general dentists. The gold standard used for the radiographic comparisons was the true position of the embedded tooth as confirmed by horizontal tube shift technique using three periapical radiographs. The general dentist examiners were instructed on the use of the modified acronym 'SLDOBU' by the radiologist as it pertains to panoramic radiographs as the principle of vertical tube shift. All of the embedded maxillary incisors and supernumeraries were successfully located using the vertical tube shift from a panoramic and a maxillary anterior periapical radiograph by the radiologist and 5 general dentists. The use of a panoramic film with a periapical film combination for a vertical tube shift can be useful to localize unerupted maxillary incisors and supernumeraries.

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

    DEFF Research Database (Denmark)

    Kjaer, I; Balslev-Olesen, M

    2012-01-01

    of the cranium and face. It is not known whether the centrally located permanent incisor is always preceded by a centrally located primary incisor. The aim was to analyse whether a permanent single central incisor in SMMCI is always preceded by a primary single central incisor and to study extra- and intraoral...

  13. Rethinking incisor size and diet in anthropoids: diet, incisor wear and incisor breadth in the African apes.

    Science.gov (United States)

    McCollum, Melanie A

    2007-07-01

    In a seminal study Hylander (1975) concluded that the length of the incisor row in catarrhines considered frugivores is longer relative to body mass than in those classified as folivores. Assuming that large fruits require greater incisal processing than do leaves, stems, berries, and seeds, he argued that the larger incisors of frugivores increased their resistance to wear. The present analysis examines diet, incisor wear, and incisor crown breadth in cranial samples of western lowland gorillas and chimpanzees. Incisor wear rate was assessed on the basis of the extent of incisor crown reduction observed at sequential stages of first molar wear. Incisor metrics were obtained from the unworn teeth of juveniles. Results suggest that incisor wear is greater in the more folivorous western lowland gorillas than in more frugivorous chimpanzees. Moreover, incisor crown dimensions do not differ appreciably among African apes. These findings fail to support the hypothesis that slower wear rates are associated with broader incisor crowns, and raise new questions regarding the significance of incisor row length in anthropoids. (c) 2007 Wiley-Liss, Inc.

  14. Removable orthodontic appliance with nickel-titanium spring to reposition the upper incisors in an autistic patient.

    Science.gov (United States)

    Saito, Kan; Jang, Insan; Kubota, Kazumi; Hoshino, Tomonori; Hotokezaka, Hitoshi; Yoshida, Noriaki; Fujiwara, Taku

    2013-01-01

    A newly designed removable appliance with a shape-memory wire was used for the orthodontic treatment of the anterior teeth in an 11-year-old child who had autism and intellectual disability. The device was designed to reduce the lateral incisor crossbite and the central incisors' labial rotation. The child was treated for 1 year with this removable appliance. Tooth movement was analyzed using cephalograms and surface data were derived from study models. This device proved to be very durable. The lateral incisor crossbite was corrected, and the inclination of the upper central incisors and the interincisal angle were improved. This appliance exerts light and continuous orthodontic force, without requiring any adjustments of the spring wire. The appliance also facilitated orthodontic treatment in a child with intellectual disability in whom treatment with a standard orthodontic device would be unsuitable. ©2012 Special Care Dentistry Association and Wiley Periodicals, Inc.

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

    Science.gov (United States)

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

    2012-10-01

    Clinicians do not frequently see impacted dilacerated maxillary incisors in their patients. When they do, there are several diagnostic and management challenges for correcting root dilacerations. An unfavorable esthetic outcome might occur as a result of soft-tissue complications during surgical eruption procedures. We present 2 patients with an impacted and dilacerated maxillary central incisor. Computed tomography scans with 3-dimensional reformation were used to accurately assess the positions of the dilacerated teeth, the degree of dilaceration, and the stage of root formation. The therapy primarily involved 2-stage crown exposure surgery combined with orthodontic traction. An apicoectomy was performed on 1 dilacerated tooth; the other exhibited pulp vitality. This article highlights the periodontal surgical strategies for the esthetic management of inverted crowns. Through periodontal plastic surgery and interdisciplinary cooperation, the impacted dilacerated central incisors were properly aligned, and successful esthetic results were achieved. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  16. Mandibular incisor apicoectomy in a Canadian Beaver.

    Science.gov (United States)

    Steenkamp, Gerhard; Venter, Leon; Crossley, David; Buss, Peter

    2009-01-01

    A 52-month-old Canadian beaver was presented for treatment of lip trauma resulting from overgrowth of the right mandibular incisor tooth following earlier loss of the right maxillary incisor tooth. Extraction of the affected tooth was considered, but rejected due to the length of the embedded portion of rodent mandibular incisor teeth. The lip injury was managed by crown reduction (odontoplasty) of the overgrowing incisor tooth pending a more permanent treatment plan. A 2-cm apicoectomy of the right mandibular incisor tooth was performed to arrest growth of the tooth when the beaver was 82-months-old. The remainder of the tooth continued to erupt and was completely expelled during a 9-month period with one additional odontoplasty being required. The beaver continued to feed normally with just the left maxillary and mandibular incisor teeth until its death at 118-months, with odontoplasty performed twice on the remaining incisor teeth during the 30-months following exfoliation.

  17. Orthodontic, genetic, and periodontal considerations in the treatment of impacted maxillary central incisors: A study of twins.

    Science.gov (United States)

    Brand, A; Akhavan, M; Tong, H; Kook, Y A; Zernik, J H

    2000-01-01

    Treatment of twins each with one impacted maxillary central incisor and a mesiodens is described. Treatment included rapid expansion, extraction of the mesiodens, surgical exposure of the impacted central incisor, and its forced eruption. The impacted incisor was brought into functional position in one patient but was lost in the other because of insufficient root length and high mobility. Orthodontic, genetic, and periodontal considerations of these 2 cases are evaluated.

  18. Mandibular Symmetrical Bilateral Canine-Lateral Incisors Transposition: Its Early Diagnosis and Treatment Considerations

    Directory of Open Access Journals (Sweden)

    Yehoshua Shapira

    2016-01-01

    Full Text Available Bilateral mandibular tooth transposition is a relatively rare dental anomaly caused by distal migration of the mandibular lateral incisors and can be detected in the early mixed dentition by radiographic examination. Early diagnosis and interceptive intervention may reduce the risk of possible transposition between the mandibular canine and lateral incisor. This report illustrates the orthodontic management of bilateral mandibular canine-lateral incisor transposition. Correct positioning of the affected teeth was achieved on the left side while teeth on the right side were aligned in their transposed position. It demonstrates the outcome of good alignment of the teeth in the dental arch.

  19. Torque Control During Intrusion on Upper Central Incisor in Labial and Lingual bracket System - A 3D Finite Element Study.

    Science.gov (United States)

    Pol, Tejas R; Vandekar, Meghna; Patil, Anuradha; Desai, Sanjana; Shetty, Vikram; Hazarika, Saptarshi

    2018-01-01

    The aim of present study was to investigate the difference of torque control during intrusive force on upper central incisors with normal, under and high torque in lingual and labial orthodontic systems through 3D finite element analysis. Six 3D models of an upper right central incisor with different torque were designed in Solid Works 2006. Software ANSYS Version 16.0 was used to evaluate intrusive force on upper central incisor model . An intrusive force of 0.15 N was applied to the bracket slot in different torque models and the displacements along a path of nodes in the upper central incisor was assessed. On application of Intrusive force on under torqued upper central incisor in Labial system produce labial crown movement but in Lingual system caused lingual movement in the apical and incisal parts. The same intrusive force in normal-torqued central incisor led to a palatal movement in apical and labial displacement of incisal edge in Lingual system and a palatal displacement in apical area and a labial movement in the incisal edge in Labial systemin. In overtorqued upper central incisor, the labial crown displacement in Labial system is more than Lingual system. In labial and lingual system on application of the same forces in upper central incisor with different inclinations showed different responses. The magnitudes of torque Loss during intrusive loads in incisors with normal, under and over-torque were higher in Labial system than Lingual orthodontic appliances. Key words: FEM, lingual orthodontics, intrusion, torque control, labial bracket systems.

  20. Effects of mandibular advancement plus prohibition of lower incisor movement on mandibular growth in rats.

    Science.gov (United States)

    Taira, Koji; Iino, Shoichiro; Kubota, Takeshi; Fukunaga, Tomohiro; Miyawaki, Shouichi

    2009-11-01

    To test the hypothesis that mandibular advancement with the use of a fixed functional appliance combined with prohibition of labial movement of the lower incisors will have no effect on mandibular growth in growing rats. Fifteen 4-week-old male rats were divided into fixed, unfixed, and control groups (n = 5, each). Bite-jumping appliances were used in the fixed and unfixed groups. Sites of bone perforation and the lower incisors were connected with ligature wires in the fixed group. The ramus height, mandibular length, and inclination of lower incisors were examined for 4 weeks, and those values were compared among five intervals and three groups by through one-way analysis of variance models and the Bonferroni multiple comparison test for post hoc comparison. Increases in ramus height and mandibular length during the experimental period were 1.5 mm and 2.5 mm in the fixed group, 1 mm and 1.5 mm in the unfixed group, and 1.2 mm and 1.9 mm in the control group, respectively. Growth of ramus height and growth of mandibular length in the fixed group were greater than in the unfixed and control groups during the experimental period. The inclination of lower incisors in the unfixed group was increased 8.0 degrees throughout the experimental period, which differed from results obtained in the other groups. Mandibular growth was accelerated effectively before and during the pubertal period in rats by mandibular advancement with a fixed functional appliance combined with prohibition of labial movement of the lower incisor.

  1. Deontological and utilitarian inclinations in moral decision making: a process dissociation approach.

    Science.gov (United States)

    Conway, Paul; Gawronski, Bertram

    2013-02-01

    Dual-process theories of moral judgment suggest that responses to moral dilemmas are guided by two moral principles: the principle of deontology states that the morality of an action depends on the intrinsic nature of the action (e.g., harming others is wrong regardless of its consequences); the principle of utilitarianism implies that the morality of an action is determined by its consequences (e.g., harming others is acceptable if it increases the well-being of a greater number of people). Despite the proposed independence of the moral inclinations reflecting these principles, previous work has relied on operationalizations in which stronger inclinations of one kind imply weaker inclinations of the other kind. The current research applied Jacoby's (1991) process dissociation procedure to independently quantify the strength of deontological and utilitarian inclinations within individuals. Study 1 confirmed the usefulness of process dissociation for capturing individual differences in deontological and utilitarian inclinations, revealing positive correlations of both inclinations to moral identity. Moreover, deontological inclinations were uniquely related to empathic concern, perspective-taking, and religiosity, whereas utilitarian inclinations were uniquely related to need for cognition. Study 2 demonstrated that cognitive load selectively reduced utilitarian inclinations, with deontological inclinations being unaffected. In Study 3, a manipulation designed to enhance empathy increased deontological inclinations, with utilitarian inclinations being unaffected. These findings provide evidence for the independent contributions of deontological and utilitarian inclinations to moral judgments, resolving many theoretical ambiguities implied by previous research. (c) 2013 APA, all rights reserved.

  2. Stress field of a dislocating inclined fault

    Energy Technology Data Exchange (ETDEWEB)

    Huang, F.; Wang, T.

    1980-02-01

    Analytical expressions are derived for the stress field caused by a rectangular dislocating fault of an arbitrary dip in a semi-infinite elastic medium for the case of unequal Lame constants. The results of computations for the stress fields on the ground surface of an inclined strike-slip and an inclined dip-slip fault are represented by contour maps. The effects of Poisson Ratio of the medium, the dip angle, upper and lower boundaries of the faults on the stress field at surface have been discussed. As an application, the contour maps for shear stress and hydrostatic stress of near fields of the Tonghai (1970), Haicheng (1975) and Tangshan (1976) earthquakes have been calculated and compared with the spatial distributions of strong aftershocks of these earthquakes. It is found that most of the strong aftershocks are distributed in the regions of tensional stress, where the hydrostatic stress is positive.

  3. Stress field of a dislocating inclined fault

    Energy Technology Data Exchange (ETDEWEB)

    Huang, F.; Wang, T.

    1980-02-01

    In this paper, analytical expressions of the stress field given rise by a rectangular dislocating fault of an arbitrary dip in a semi-infinite elastic medium for the case of unequal Lame constants are derived. The results of computations for the stress fields on the ground surface of an inclined strike-slip and an inclined dip-slip fault are represented by contour maps. The effects of the Poisson Ratio of the medium, the dip angle, upper and lower boundaries of the faults on the stress field at the surface have been discussed. As an application, the contour maps for shear stress and hydrostatic stress of near fields of the Tonghai (1970), Haicheng, (1975) and Tangshan (1976) earthquakes have been calculated and compared with the spatial distributions of strong aftershocks of these earthquakes. It is found that most of the strong aftershocks are distributed in the regions of tensional stress where the hydrostatic stress is positive.

  4. Association between maxillary anterior supernumerary teeth and impacted incisors in mixed dentition.

    Science.gov (United States)

    He, Dongmei; Mei, Li; Wang, Yan; Li, Jialing; Li, Huang

    2017-08-01

    Few researchers have investigated the relationship between supernumerary teeth (ST) and impacted incisors. The authors investigated the relationship between ST and impacted incisors in the maxillary anterior area in the mixed dentition. Using cone-beam computed tomography, the authors diagnosed 417 ST among 294 patients (age range, 6-12 years; 220 boys and 74 girls). The number, morphology, growth orientation, and position of ST were recorded along with the presence of impacted incisors. The authors reported that 23.1% of patients having ST (n = 68; mean [standard deviation] age 8.5 [1.6] years) also had impacted incisors. Morphology (molariform and odontomelike), growth orientation (normal and no orientation), and position (coronal) of the ST were significantly associated with impacted incisors (P < .05 for all). An increase of 1 year in age was associated with a decreased risk of having ST accompanied by impacted incisors (odds ratio, 0.76; 95% confidence interval, 0.63 to 0.92). An increase of 1 ST more than doubled the risk of having an impacted incisor (odds ratio, 2.39; 95% confidence interval, 1.44 to 3.96). In this population, the number, morphology, growth orientation, and position of ST as well as the patient's age were associated with impacted incisors in the maxillary anterior area during the mixed dentition. The presence and morphology of ST should alert the clinician to the increased likelihood of having impacted incisors and the need for early diagnosis and appropriate treatment. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    1997-01-01

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

  6. Outcome of orthodontic space closure with a missing maxillary central incisor.

    Science.gov (United States)

    Czochrowska, Ewa M; Skaare, Anne B; Stenvik, Arild; Zachrisson, Björn U

    2003-06-01

    Orthodontic space closure is one of the treatment alternatives when a maxillary central incisor is missing. Because no systematic analysis of such treatment results is available, a sample of 20 consecutively treated patients was examined in a follow-up study. All patients had received orthodontic treatment with the objective of closing the space for the missing central incisor. Biologic features and the clinical appearance of the recontoured lateral incisor (test tooth) replacing the missing tooth were compared with the neighboring intact central incisor, which served as control tooth. The patients' opinions regarding the treatment and the result were recorded in a questionnaire. The position of the examined teeth and the appearance of the surrounding soft tissues were similar in the test and control teeth. However, in some patients (25%), certain aspects of the recontoured incisor crown (such as the width at the gingival margin) mismatched the appearance of the controls. A somewhat increased mobility and probing pocket depth on the mesial aspect was recorded for some test teeth. No obvious detrimental effects were observed on the radiographs. Most patients expressed satisfaction with the treatment result. It is concluded that orthodontic mesialization of the lateral incisor to replace a missing central incisor is a valid treatment modality, if the indications for such treatment are present and careful attention to detail in orthodontic and restorative treatment is exercised.

  7. [Incisors with a mind of their own

    NARCIS (Netherlands)

    Heumen, C.C.M. van; Termeer, D.; Oosterkamp, B.C.; Meijer, G.J.

    2014-01-01

    A 43-year-old man, known to have hypodontia, was bothered by his over-erupted central incisors. After the placement of implants and the accompanying crown- and bridgework, the central incisors appear to be increasingly over-erupted. The history shows that this phenomenon has already been seen in the

  8. Solitary median maxillary central incisor (SMMCI syndrome

    Directory of Open Access Journals (Sweden)

    Hall Roger K

    2006-04-01

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

  9. Pool Boiling CHF in Inclined Narrow Annuli

    International Nuclear Information System (INIS)

    Kang, Myeong Gie

    2010-01-01

    Pool boiling heat transfer has been studied extensively since it is frequently encountered in various heat transfer equipment. Recently, it has been widely investigated in nuclear power plants for application to the advanced light water reactors designs. Through the review on the published results it can be concluded that knowledge on the combined effects of the surface orientation and a confined space on pool boiling heat transfer is of great practical importance and also of great academic interest. Fujita et al. investigated pool boiling heat transfer, from boiling inception to the critical heat flux (CHF, q' CHF ), in a confined narrow space between heated and unheated parallel rectangular plates. They identified that both the confined space and the surface orientation changed heat transfer much. Kim and Suh changed the surface orientation angles of a downward heating rectangular channel having a narrow gap from the downward-facing position (180 .deg.) to the vertical position (90 .deg.). They observed that the CHF generally decreased as the inclination angle (θ ) increased. Yao and Chang studied pool boiling heat transfer in a confined heat transfer for vertical narrow annuli with closed bottoms. They observed that when the gap size ( s ) of the annulus was decreased the effect of space confinement to boiling heat transfer increased. The CHF was occurred at much lower value for the confined space comparing to the unconfined pool boiling. Pool boiling heat transfer in narrow horizontal annular crevices was studied by Hung and Yao. They concluded that the CHF decreased with decreasing gap size of the annuli and described the importance of the thin film evaporation to explain the lower CHF of narrow crevices. The effect of the inclination angle on the CHF on countercurrent boiling in an inclined uniformly heated tube with closed bottoms was also studied by Liu et al. They concluded that the CHF reduced with the inclination angle decrease. A study was carried out

  10. Uplift Capacity of Inclined Underreamed Piles Subjected to Vertical Load

    Science.gov (United States)

    Rahman, Md. Akilur; Sengupta, Siddhartha

    2017-12-01

    Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Inclined (batter) piles are used to support such structures, and to carry the horizontal and vertical loads resulted from the overturning moments. Though studies have been done with inclined piles having no underream bulb, little information is available in the literature about estimating the uplift capacity of inclined underreamed piles. In the present study laboratory experiments have been done with vertically loaded model piles having no underream as well as with one and two underreams. The piles were positioned at angle of inclination of θ = 0°, 10°, 20°, 30° (with vertical); and placed in locally available sand under vertical uplift load. Three different pile stem diameters (D = 20, 25, and 35 mm) were used. The corresponding pile length to stem diameter (l/D) ratio were 18, 14, and 10 respectively. Experiments had been conducted with two relative different densities (45 and 70%) of sand. The failure uplift loads were obtained in each case. It had been found that for inclined piles increase in number of underream bulbs from 0 to 2 was quite effective in resisting uplift loads corresponding to piles having l/D equals to 10. The percentage decreases in uplift capacity corresponding to increase in inclination angle were more pronounced for piles with double underreams.

  11. Biomechanical considerations in mandibular incisor extraction cases.

    Science.gov (United States)

    Rachala, Madhukar Reddy; Aileni, Kaladhar Reddy; Dasari, Arun Kumar; Sinojiya, Jay

    2015-01-01

    Mandibular incisor extraction can be regarded as a valuable treatment option in certain malocclusions to obtain excellence in orthodontic results in terms of function, aesthetics and stability. This treatment alternative is indicated in clinical situations like mild to moderate class III malocclusion, mild anterior mandibular tooth size excess, periodontally compromised teeth, ectopic eruption of mandibular incisor and minimal openbite tendencies. Unlike in premolar extraction cases, space closure in mandibular incisor extraction cases is unique in which the extraction space will be in the middle of the arch. The end result of space closure in these cases should be well aligned, upright, anterior teeth with parallel roots and the goal can be achieved with the bodily tooth movement through proper application of biomechanics. The purpose of this article is to explain the biomechanics of space closure in mandibular incisor extraction cases.

  12. Compound odontome with unerupted permanent incisor

    Directory of Open Access Journals (Sweden)

    Mahfujul Haq Khan

    2011-01-01

    Full Text Available Odontomas are mixed odontogenic tumors composed of both epithelial and mesenchymal dental hard tissues. They are usually asymptomatic and are often discovered during routine radiography. A case of odontoma in a 21 year old man is described who presented with delayed eruption of upper central and lateral incisor teeth. The odontome was surgically removed followed by re-implantation of preserved extracted lateral incisor and a porcelain crown. Ibrahim Med. Coll. J. 2011; 5(1: 29-31

  13. Molar incisor hypomineralization: current research evidences

    OpenAIRE

    Manikandan Ekambaram

    2016-01-01

    Molar-Incisor Hypomineralization (MIH) is a condition of systemic origin that involves one to four first permanent molar teeth and often associated with affected incisors. Although several associations to prenatal/perinatal childhood medical conditions have been reported, the etiology of MIH still remains unclear. The degree of enamel hypomineralization in the affected teeth can vary and the clinical problems associated with the teeth include increased susceptibility to caries, rapid wear, an...

  14. Three-dimensional anatomy of equine incisors: tooth length, enamel cover and age related changes.

    Science.gov (United States)

    Schrock, Patricia; Lüpke, Matthias; Seifert, Hermann; Staszyk, Carsten

    2013-12-09

    Equine incisors are subjected to continuous occlusal wear causing multiple, age related changes of the extragingival crown. It is assumed that the occlusal wear is compensated by continued tooth elongation at the apical ends of the teeth. In this study, μCT-datasets offered the opportunity to analyze the three-dimensional appearance of the extra- and intraalveolar parts of the enamel containing dental crown as well as of the enamel-free dental root. Multiple morphometric measurements elucidated age related, morphological changes within the intraalveolar part of the incisors. Equine incisors possess a unique enamel cover displaying large indentations on the mesial and distal sides. After eruption tooth elongation at the apical end outbalances occlusal wear for two to four years resulting in increasing incisor length in this period of time. Remarkably, this maximum length is maintained for about ten years, up to a tooth age of 13 to 15 years post eruption. Variances in the total length of individual teeth are related to different Triadan positions (central-, middle- and corner incisors) as well as to the upper and lower arcades. Equine incisors are able to fully compensate occlusal wear for a limited period of time. However, after this ability ceases, it is expected that a diminished intraalveolar tooth length will cause massive changes in periodontal biomechanics. The time point of these morphodynamic and biomechanical changes (13 to 15 years post eruption) occurs in coincidence with the onset of a recently described destructive disease of equine incisor (equine odontoclastic tooth resorption and hypercementosis) in aged horses. However, further biomechanical, cell biological and microbiological investigations are needed to elucidate a correlation between age related changes of incisor morphology and this disease.

  15. Three-dimensional anatomy of equine incisors: tooth length, enamel cover and age related changes

    Science.gov (United States)

    2013-01-01

    Background Equine incisors are subjected to continuous occlusal wear causing multiple, age related changes of the extragingival crown. It is assumed that the occlusal wear is compensated by continued tooth elongation at the apical ends of the teeth. In this study, μCT-datasets offered the opportunity to analyze the three-dimensional appearance of the extra- and intraalveolar parts of the enamel containing dental crown as well as of the enamel-free dental root. Multiple morphometric measurements elucidated age related, morphological changes within the intraalveolar part of the incisors. Results Equine incisors possess a unique enamel cover displaying large indentations on the mesial and distal sides. After eruption tooth elongation at the apical end outbalances occlusal wear for two to four years resulting in increasing incisor length in this period of time. Remarkably, this maximum length is maintained for about ten years, up to a tooth age of 13 to 15 years post eruption. Variances in the total length of individual teeth are related to different Triadan positions (central-, middle- and corner incisors) as well as to the upper and lower arcades. Conclusion Equine incisors are able to fully compensate occlusal wear for a limited period of time. However, after this ability ceases, it is expected that a diminished intraalveolar tooth length will cause massive changes in periodontal biomechanics. The time point of these morphodynamic and biomechanical changes (13 to 15 years post eruption) occurs in coincidence with the onset of a recently described destructive disease of equine incisor (equine odontoclastic tooth resorption and hypercementosis) in aged horses. However, further biomechanical, cell biological and microbiological investigations are needed to elucidate a correlation between age related changes of incisor morphology and this disease. PMID:24321365

  16. Dental fast track: prenatal enamel growth, incisor eruption, and weaning in human infants.

    Science.gov (United States)

    Mahoney, Patrick

    2015-03-01

    Correlation between the timing of permanent first molar eruption and weaning age in extant primates has provided a way to infer a life history event in fossil species, but recent debate has questioned whether the same link is present in human infants. Deciduous incisors erupt at an age when breast milk can be supplemented with additional foods (mixed feeding), and weaning is typically complete before permanent first molars erupt. Here, I use histological methods to calculate the prenatal rate by which enamel increases in thickness and height on human deciduous incisors, canines, and molars (n = 125). Growth trajectories for each tooth type are related to the trimesters and assessed against the eruption sequence and final crown height. Analyses show that central incisors initiate early in the second trimester with significantly faster secretion rates relative to canines and second molars, which initiate closer to birth. Even though initial extension rates were correlated with crown height and scaled with positive allometry within each tooth class, the relatively short incisors still increased in height at a significantly faster rate than the taller canines and molars. The incisor prenatal "fast track" produces a greater proportion of the crown before birth than all other tooth types. This growth mechanism likely facilitates early incisor eruption at a time when the mixed feeding of infants can be initiated as part of the weaning process. Findings provide a basis from which to explore new links between developmental trends along the tooth row and mixed feeding age in other primates. © 2014 Wiley Periodicals, Inc.

  17. Impacted maxillary central incisor: surgical exposure and orthodontic treatment.

    Science.gov (United States)

    Pinho, Teresa; Neves, Manuel; Alves, Célia

    2011-08-01

    This case report describes the treatment of a patient with a horizontally impacted maxillary central incisor, a canine in the same quadrant, and an inclusion tendency. Due to severe crowing in the maxilla and the Class II molar relationship on the impaction side, a 2-stage treatment plan was developed. In the first stage, the right first premolar and deciduous canine were extracted; this allowed enough space for the eruption of the maxillary right permanent canine. The second stage included surgical exposure and traction of the impacted central incisor with a fixed orthodontic appliance. An excisional uncovering technique was needed to expose the impacted incisor. After it erupted, an apically positioned partial-thickness flap was used to add keratinized attached gingiva in the area surrounding the crown, initially located in an area of unattached gingiva. The patient finished treatment with a normal and stable occlusion between the maxillary and mandibular arches and an adequate width of attached gingiva. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  18. Dental repercussions of maxillary lateral incisor agenesis.

    Science.gov (United States)

    Pinho, Teresa; Lemos, Carolina

    2012-12-01

    The aim of this study was to assess the influence of maxillary lateral incisor agenesis (MLIA) on the position of other teeth in the dental arch. The sample consisted of 147 individuals (66 males and 81 females) divided into two age groups: a growth phase group (A) comprising 43 individuals (18 males and 25 females, ages ranging from 9 to 16 years) and an adult group (B) (with females older than 14 and males older than 18 years) comprising 104 individuals (48 males and 56 females, ages ranging from 15 to 45 years). Within these groups, the individuals were then divided into three subsets: group 1 with MLIA, group 2 relatives of group 1 but without MLIA, and group 3 individuals from the general population (without agenesis and unrelated). Clinical evaluation of the maxillary dental midline and of the antero-posterior relationship between the upper and lower arches at the first permanent molars and canines was performed. Variables were compared by a chi-square test. There was a significant (P dental midline. MLIA was associated with a Class II malocclusion; this was more frequent on the same side as the agenesis.

  19. Unusual Case of Extraction of Maxillary Lateral Incisors and Mandibular Central Incisors

    Directory of Open Access Journals (Sweden)

    Rosa-María Yañez-Vico

    2017-01-01

    Full Text Available Introduction. This article’s purpose is to report a case where maxillary lateral incisors and mandibular central incisors are extracted and a canine substitution was performed as the best therapeutic option in order to obtain symmetry in a malocclusion with an upper lateral incisor with poor prognostic, solve moderate crowding, get enough space for the permanent dentition, and provide stability to the results. Case Report. An 11-year-old boy with straight profile with acute-to-normal nasolabial angle and protruded lips, mixed dentition, lower and upper severe crowding, and a bilateral molar angle Class I. The left maxillary lateral incisor failed endodontic treatment secondary to an intrusive traumatic lesion in the primary and permanent dentition. The treatment of choice was the extraction of both upper lateral incisors and both central lower incisors. The patient finished with molar and canine angle Class I and coincident midlines and was functionally stable; both lateral and protrusive jaw movements were effectively made by the first premolars and central incisors and canines without improper contacts of the rest of the teeth. Overbite of one-third and correct overjet were also achieved, and the esthetic outcome was satisfactory due to the composed material restorations of both the central and lateral incisors, as well as recontouring of the first maxillary premolars.

  20. Management of a rare case of impacted primary central incisors in a 3-year-old child

    Directory of Open Access Journals (Sweden)

    A Sharma

    2012-01-01

    Full Text Available Impaction of primary anterior teeth is very rare. A tooth that fails to erupt into normal functional position by the time it normally should is considered impacted. A rare case of impacted dilacerated maxillary primary incisors in a 3-year-old child is presented. The diagnostic position of impacted primary incisors was determined using conical beam computed tomography (CBCT to assist in surgical intervention with least surgical trauma to the tissues.

  1. Estudo da função muscular peribucal, do grau de inclinação vestíbulo-lingual e da discrepância de modelo dos incisivos inferiores permanentes em crianças respiradoras nasais e bucais com oclusão normal e má oclusão de Classe I A perioral muscles activity, buccal-lingual inclination and space discrepancy of the lower incisors study, in mouth or nasal breathing children with normal or Class I malocclusion

    Directory of Open Access Journals (Sweden)

    Sabine W. Vieira

    2005-02-01

    electromyographic tests, the quantitative assessment of the buccal-lingual inclination (FMIA and space discrepancy (DM of the permanent lower incisors. Obtained results were submitted to statistic methods and showed no significant statistical difference for the dental variables and for the majority of the electromyographic variables studied. In this way, the clinically assessed mouth breathing could not be associated to the oclusal features and muscular functions studied.

  2. Mandibular meslodens with agenesis of central incisors - A rare ...

    African Journals Online (AJOL)

    Mesiodens is commonly located in maxillary central incisor region and rarely in the mandible. Congenital absence of mandibular central incisor is uncommon. This is a report of a rare association of mandibular mesiodens with congenitally absent permanent central incisors. This is the first case report of such an association.

  3. The effect of anterior inclined plane treatment on the dentoskeletal of Class II division 1 patients

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    Emami Meibodi

    2007-09-01

    Full Text Available Most of Class II malocclusions are due to underdeveloped mandible with increased overjet and overbite. Lack of incisal contact results in the extrusion of the upper and lower anterior dentoalveolar complex, which helps to lock the mandible and prevent its normal growth and development, and this abnormality is exaggerated by soft tissue imbalance. The purpose of this study was to evaluate the skeletal and dental changes in patients treated with anterior inclined plane appliance in growing patients with moderate Class II Division 1 having deep overbite. In this study, 25 patients, including 15 girls and 10 boys, with a mean age of 9 ±1.2 years were selected; all of them presented with moderate Class II deep bite with increased overjet and normal or horizontal growth pattern. Pre- and post-treatment X-rays and photos for an average of 8 months were taken. The statistical assessment of the data suggested that there were no significant changes in the vertical skeletal parameters. The mandibular incisors were protruded, whereas the maxillary incisors were retruded. Overbite and overjet were also reduced. There was significant increase in the mandibular length. The results revealed that in mixed dentition patients, the inclined plane corrected Class II discrepancies mostly through dentoskeletal changes.

  4. Efeitos dos fios de nivelamento de níquel-titânio e de aço inoxidável na posição dos incisivos inferiores Effects of nickel-titanium and stainless steel leveling wires on the position of mandibular incisors

    Directory of Open Access Journals (Sweden)

    Ricardo Moresca

    2011-10-01

    Full Text Available OBJETIVO: estudar os efeitos do nivelamento realizado com fios de NiTi termoativado e de aço inoxidável, avaliando-se as possíveis alterações na posição dos incisivos inferiores, em casos com extrações, correlacionando com o tempo de tratamento. MÉTODOS: a amostra foi composta de 36 indivíduos, de ambos os sexos, leucodermas brasileiros, com idade média inicial de 15 anos e 5 meses, portadores de más oclusões de Classes I e II, distribuídos em dois grupos. No Grupo 1 (n=17, o nivelamento foi realizado com a sequência 1, utilizando-se três fios - 0,016" e 0,019"x0,025" de NiTi termoativado, e 0,019"x0,025" de aço inoxidável. No Grupo 2 (n=19, foi testada a sequência 2, na qual foram utilizados apenas fios de aço inoxidável (0,014"; 0,016"; 0,018"; 0,020" e 0,019"x0,025" com torque passivo nos incisivos inferiores. Os dados foram coletados utilizando-se o método cefalométrico computadorizado e comparados pelo teste t de Student com o nível de significância de 5%. RESULTADOS: no Grupo 1, os incisivos inferiores inclinaram-se para lingual, com movimento significativo apenas da coroa (1,6mm. No Grupo 2, os incisivos inferiores permaneceram estáveis. Não houve alteração vertical em nenhum dos grupos. CONCLUSÕES: a sequência 2 proporcionou um melhor controle dos incisivos inferiores, não alterando suas posições iniciais, enquanto a sequência 1 permitiu a expressão do torque da prescrição utilizada, levando a uma inclinação lingual desses dentes. O tempo de tratamento foi menor utilizando-se a sequência 1. As variações biomecânicas estudadas apresentaram vantagens e desvantagens que devem ser conhecidas e ponderadas pelo ortodontista no planejamento do caso.OBJECTIVE: To study the effects of the leveling phase performed with heat activated NiTi and stainless steel archwires evaluating the possible changes in lower incisors position in extraction cases, as well as its correlation with treatment time. METHODS

  5. Incisors as digging tools in molerats (Bathyergidae)

    African Journals Online (AJOL)

    1998-03-26

    Xa and Vb) at which the upper and lower incisors (lines a- ..... JARVIS. JU.M., BENNETT. N.C. 1991. Introducing the Alriean mole-rats (family Bathyergidae). In: The biology of the naked mole-rat: 66 - 96. (Eds) Sherman. R. W ..

  6. Deciduous molar hypomineralization and molar incisor hypomineralization

    NARCIS (Netherlands)

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

    2012-01-01

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

  7. Molar incisor hypomineralization, prevalence, and etiology.

    Science.gov (United States)

    Allazzam, Sulaiman Mohammed; Alaki, Sumer Madani; El Meligy, Omar Abdel Sadek

    2014-01-01

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

  8. Molar Incisor Hypomineralization, Prevalence, and Etiology

    Directory of Open Access Journals (Sweden)

    Sulaiman Mohammed Allazzam

    2014-01-01

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

  9. [Upper lateral incisor with 2 canals].

    Science.gov (United States)

    Fabra Campos, H

    1991-01-01

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

  10. Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization.

    Science.gov (United States)

    Negre-Barber, A; Montiel-Company, J M; Boronat-Catalá, M; Catalá-Pizarro, M; Almerich-Silla, J M

    2016-08-25

    Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of Paediatric Dentistry. 100 children (24.2%) presented MIH and 60 (14.5%) presented HSPM. Co-occurrence of the two defects was observed in 11.1% of the children examined. The positive predictive value was 76.7% (63.9-86.6) and the negative predictive value 84.7% (80.6-88.3). The positive likelihood ratio (S/1-E) was 10.3 (5.9-17.9) and the negative likelihood ratio (1-S/E) 0.57 (0.47-0.68). The odds ratio was 18.2 (9.39-35.48). It was concluded that while the presence of HSPM can be considered a predictor of MIH, indicating the need for monitoring and control, the absence of this defect in primary dentition does not rule out the appearance of MIH.

  11. Alveolar bone width preservation after decoronation of ankylosed anterior incisors.

    Science.gov (United States)

    Lin, Shaul; Schwarz-Arad, Dvorah; Ashkenazi, Malka

    2013-12-01

    The aim of the study was to assess the alteration of alveolar ridge dimensions after decoronation procedures in children and adolescents at least 1 year after surgery. Twelve children who underwent decoronation of ankylosed maxillary anterior incisors with at least 1 year after surgery follow-up were recalled for reevaluation. All decoronations were performed when the ankylosed teeth were submerged 1-1.5 mm. During the recall appointment, impressions of the upper arch were obtained. The bucco-palatal alveolar dimensions of the decoronated teeth were measured on the cast at the mid-mesiodistal distance from the missing tooth and were compared with the distance from the contralateral healthy incisor. Overall, 12 children (9 male and 3 female) were reevaluated up to 82 months after decoronation (mean, 49.58 ± 24 months). The mean age of the patients at the time of trauma was 9.83 ± 2.8 years. The average bucco-palatal dimension of the alveolar ridge at the mid-decoronation area was 9 ± 1 mm compared with 10.17 ± 0.9 mm at the contralateral homologous tooth (difference of 1.67 ± 1.12, P = .004). The findings show a positive statistical correlation between the duration of the follow-up period and the bucco-palatal dimension of the alveolar ridge (P = .027). Although decoronation of ankylosed young permanent incisors resulted in a decrease in the bucco-palatal dimension with time, it did not prevent additional alveolar growth that occurs with age in a developing child and thus may help maintain the alveolar bone ridge width, height, and continuity and assist in future rehabilitation with less invasive ridge augmentation procedures required for implant placement. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

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    Hiroko eOhmori

    2012-06-01

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

  13. Radiographic technique and brackets affect measurements of proximal enamel thickness on mandibular incisors

    NARCIS (Netherlands)

    Ang, Amy Giok Phing; Steegmans, Pauline Antoinette Josephine; Kerdijk, Wouter; Livas, Christos; Ren, Yijin

    2017-01-01

    Objective: To investigate the influence of radiographic film and tube positioning, the presence and the size of brackets on in vitro measurements of proximal enamel thickness of mandibular incisors on periapical radiographs aimed to aid planning of interproximal enamel reduction procedures in

  14. Towards red-edge positions less sensitive to canopy biophysical parameters for leaf chlorophyll estimation using properties optique spectrales des feuilles (PROSPECT) and scattering by arbitrarily inclined leaves (SAILH) simulated data

    NARCIS (Netherlands)

    Cho, M.A.; Skidmore, A.K.; Atzberger, C.

    2008-01-01

    Several methods for extracting the chlorophyll sensitive red-edge position (REP) from hyperspectral data are reported in literature. This study is a continuation of a recent paper published as 'A new technique for extracting the red edge position from hyperspectral data: the linear extrapolation

  15. [Sequence orthodontic treatment of impacted dilacerated maxillary central incisors].

    Science.gov (United States)

    Zheng, Yi; Pang, Xuannai; Nan, Lan; Mo, Shuixue

    2012-06-01

    To explore an effective orthodontic method for treating impacted dilacerated maxillary central incisors. 12 impacted teeth of 11 cases were chosen. The position of the impacted teeth and the relations with neighbour tissues were assessed by X-ray images, oral examination and plaster model, etc. The impacted teeth were induced to erupt with the closed-eruption technique and fixed orthodontic appliances, root canal therapy, apicoectomy and prosthetic treatment. 12 impacted teeth were moved into arches, and the occlusal relationship was normal. There were no root resorption or conglutination in those impacted teeth. The labial impacted teeth of nine cases had bigger labial crown torsion. The root apexes of four impacted teeth were palpable under mucosa of the labial sulcus and operated by root canal therapy and apicoectomy. One of them received prosthetic treatment. Others (five cases) hadn't accepted root canal therapy, and were observed temporarily. The effects of two palatal impacted teeth was stable. It was a good method to expand indication with sequence orthodontic treatment. The impacted dilacerated maxillary central incisors could be aligned with good esthetical and functional effect.

  16. First contact: understanding the relationship between hominoid incisor curvature and diet.

    Science.gov (United States)

    Deane, Andrew

    2009-03-01

    Accurately interpreting fossil primate dietary behaviour is necessary to fully understand a species' ecology and connection to its environment. Traditional methods developed to infer diet from hominoid teeth successfully group taxa into broad dietary categories (i.e., folivore, frugivore) but often fail to represent the range of dietary variability characteristic of living apes. This oversimplification is not only a consequence of poor resolution, but may also reflect the use of similar fallback resources by closely related taxa with dissimilar diets. This study demonstrates that additional dietary specificity can be achieved using a morphometric approach to hominoid incisor curvature. High-resolution polynomial curve fitting (HR-PCF) was used to quantify the incisor curvatures of closely related hominoid taxa that have dissimilar diets but similar morphological adaptations to specific keystone resources (e.g., Gorilla gorilla beringei vs. G. g. gorilla). Given the key role of incisors in food processing, it is reasonable to assume that these teeth will be at least partially influenced by the unique selective pressures imposed by the mechanical loading specific to individual diets. Results from this study identify a strong correlation between hominoid dietary proportions and incisor linear dimensions and curvature, indicating that more pronounced incisor curvature is positively correlated with higher levels of frugivory. Hard-object frugivores have the greatest mesiodistal and cervico-incisal curvature and dedicated folivores have the least curved incisors. Mixed folivore/frugivores are morphological intermediates between dedicated folivores and hard- and soft-object frugivores. Mesiodistal curvature varied only in the degree of curvature; however, cervico-incisal curvature was shown to differ qualitatively between more frugivorous and more folivorous taxa. In addition to identifying a greater range of dietary variability among hominoids, this study also

  17. Molar incisor hypomineralization: current research evidences

    Directory of Open Access Journals (Sweden)

    Manikandan Ekambaram

    2016-06-01

    Full Text Available Molar-Incisor Hypomineralization (MIH is a condition of systemic origin that involves one to four first permanent molar teeth and often associated with affected incisors. Although several associations to prenatal/perinatal childhood medical conditions have been reported, the etiology of MIH still remains unclear. The degree of enamel hypomineralization in the affected teeth can vary and the clinical problems associated with the teeth include increased susceptibility to caries, rapid wear, and post-eruptive enamel breakdown. Affected teeth are extremely challenging to treat as the enamel is porous, sensitive and treating clinicians might encounter great difficulty in achieving profound anaesthesia. The first part of thispresentation will give an update on prevalence, potential etiological factors, and management strategies of this condition. The second part of the presentation will cover a systematic review results on bonding strategies to hypomineralized enamel.

  18. Bilateral fusion of permanent maxillary incisors

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Hans

    2011-01-01

    Full Text Available Dental fusion is a rare developmental anomaly, which is included in the anomalies of tooth morphology or shape. Fusion can occur at the level of enamel or enamel and dentin, which results in the formation of a single tooth with enlarged clinical crown. Fusion is more common in deciduous dentition. Incisors are reported to be fused in primary and permanent dentition, but bilateral fusion is a rare occurrence. The prevalence of bilateral fusion in the permanent dentition is less frequent than unilateral fusion and is reported to be around 0.05%. The authors report a case of a 20-year-old male with bilateral fusion of maxillary central and lateral incisors. Multi-disciplinary treatment approach is essential to get the desired esthetic result. The best way to manage these difficult cases depends on a number of factors including the knowledge and technical skills of the practitioner.

  19. Management of Congenitally Missing Lateral Incisor

    Directory of Open Access Journals (Sweden)

    Nidhi Kedia

    2011-01-01

    Full Text Available Multiple treatment options are available to patients who have congenitally missing teeth. Management options for the treatment of missing teeth can include the following: (1 Orthodontic space closure and adjacent tooth substitution, (2 autotransplantation, (3 prosthetic replacement with resin-bonded fixed partial dentures, conventional fixed partial dentures and single-tooth implants. In this case report, treatment of a patient with congenitally missing maxillary right lateral incisor will be presented.

  20. Bilateral fusion of permanent maxillary incisors

    OpenAIRE

    Manoj Kumar Hans; Shashit Shetty; Hitesh Chopra

    2011-01-01

    Dental fusion is a rare developmental anomaly, which is included in the anomalies of tooth morphology or shape. Fusion can occur at the level of enamel or enamel and dentin, which results in the formation of a single tooth with enlarged clinical crown. Fusion is more common in deciduous dentition. Incisors are reported to be fused in primary and permanent dentition, but bilateral fusion is a rare occurrence. The prevalence of bilateral fusion in the permanent dentition is less frequent than u...

  1. Molar Incisor Hypomineralization, Prevalence, and Etiology

    OpenAIRE

    Allazzam, Sulaiman Mohammed; Alaki, Sumer Madani; El Meligy, Omar Abdel Sadek

    2014-01-01

    Aim. To evaluate the prevalence and possible etiological factors associated with molar incisor hypomineralization (MIH) among a group of children in Jeddah, Saudi Arabia. Methods. A group of 8-12-year-old children were recruited (n = 267) from the Pediatric Dental Clinics at the Faculty of Dentistry, King Abdulaziz University. Children had at least one first permanent molar (FPM), erupted or partially erupted. Demographic information, children's medical history, and pregnancy-related data wer...

  2. Morphological variation of the maxillary lateral incisor

    Directory of Open Access Journals (Sweden)

    Shintaro Kondo

    2014-11-01

    Full Text Available The maxillary lateral incisor is a variable tooth morphologically. This tooth frequently shows reduction in size, and also various alterations in shape, for example, peg-shaped, cone-shaped, barrel-shaped and canine-shaped. The lateral incisor variant can be analyzed by family studies and using twin models, and these approaches have shown that genetic, epigenetic and environmental factors can all contribute to variation in the trait. Discordance of the phenotype in monozygotic twin pairs could be explained by the following two hypotheses: (1 the embryological environment of monochorionic twin pairs who share the same placenta and chorionic membrane during the prenatal period may differ, (2 phenotypic variation may be caused by epigenetic influences. Possible developmental factors are discussed in this review. Recent studies suggest that Msx1, Pax9 and Axin2 genes predispose to lateral incisor agenesis. Tooth reduction and agenesis seem to represent inter-related complex multifactorial traits, influenced by a combination of gene expression and function, environmental interaction and developing timing. Thus, accumulation of large data banks of morphological data is needed to support and clarify ongoing molecular genetic studies of dental development.

  3. Entrepreneurial inclinations of women from rural areas

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    Marković-Savić Olivera S.

    2014-01-01

    Full Text Available Entrepreneurial inclinations of women from rural areas are shaped by the lack of business ideas and economic capital, which, in addition to financial resources, includes cultural capital in the form of knowledge and skills. The paper presents a part of a broader study on the social position of women from the rural areas of northern Kosovo and Metohija, conducted in 2013. The research was predominantly focused on entrepreneurial inclinations of rural women, and the findings suggest that private enterprise in the studied population is undeveloped as a result of two dominant reasons. The first reason is the situation which is unfavorable in terms of politics and security, and therefore, not conducive to investment security, together with the specificity in the form of complex administrative business conditions requiring compliance to parallel and mutually incompatible standards (of the Republic of Serbia and of the UNMIK administration. The second important reason for the lack of entrepreneurial initiatives is the lack of ownership of property and the means of production, since banks do not give loans without guarantees in the form of ownership of the mortgage, while other forms of financial incentives are unavailable. The respondents attended programs for acquiring new knowledge and skills only in a small number of cases, while showing the greatest susceptibility to education in traditional skills, such as training in agriculture and handicrafts, which are not the skills in line with the needs of the labor market. As the most important reasons that -prevent them from having their own business, the respondents -mentioned: the lack of ideas and the lack of financial resources. In this regard, they would find incentives in the form of grants most helpful to start their own business. The absence of funds and gender inequality form the basis for the lack of ownership of property and means of production. In addition to the shortage of financial

  4. Retention of permanent incisors by mesiodens: a family affair.

    Science.gov (United States)

    Gallas, M M; García, A

    2000-01-22

    The term mesiodens refers to a supernumerary tooth that is present in the midline of the maxilla between the two central incisors. One or two mesiodentes may be present. We present a rare case of two sisters, in both of whom a pair of mesiodentes caused the retention of permanent incisors. They were referred to our hospital with asymptomatic delayed eruption of upper incisors. This article is written to point out genetic factors as the possible origin of supernumerary teeth.

  5. Fused upper central incisors: management of two clinical cases

    OpenAIRE

    Sfasciotti, Gian Luca; Marini, Roberta; Bossù, Maurizio; Ierardo, Gaetano; Annibali, Susanna

    2012-01-01

    This paper reports the management of two clinical cases, in which the upper right central incisor was fused with a supernumerary tooth and the upper left central incisor was macrodontic. A radiographic examination revealed that the fused teeth had two separate roots. Hemisectioning of the fused teeth was performed, the supernumerary portion was extracted and the remaining part was reshaped to remove any sharp margins and to achieve a normal morphology. The macrodontic central incisors were no...

  6. Molar-incisor hypomineralization: Therapeutic challenge to paediatric dentistry practice

    OpenAIRE

    Stojković Branislava; Kostadinović Ljiljana; Igić Marija; Tričković-Janjić Olivera; Stojanović Simona; Janošević Predrag

    2017-01-01

    Introduction: Molar incisor hypomineralization indicates the appearance of enamel hypomineralization of systemic origin which occurs in 1-4 first permanent molars, which is often accompanied by changes on permanent incisors. Variations in clinical manifestation, together with commonly present asymmetry, are the reason for large variations in the needs for therapeutic treatment of these structural enamel defects. Case study: Two patients with diagnosed molar incisor hypomineralization are show...

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

    Directory of Open Access Journals (Sweden)

    Guilherme Thiesen

    2015-10-01

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

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

    Science.gov (United States)

    Thiesen, Guilherme

    2015-10-01

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

  9. Management of Traumatized Permanent Incisors. Revascularization and Delayed Replantation.

    Science.gov (United States)

    Gharechahi, Maryam; Shojaeian, Shiva

    2016-01-01

    This article reports a clinical case of a 9-year-old boy with a traumatic injury to the maxillary central incisors 24 hours after a fall in his schoolyard. The upper left central incisor was avulsed and was kept in saliva for four hours from the moment of trauma until its replantation. The right one was necrotized after one month. We describe successful revascularization treatment of right necrotic immature upper incisor and delayed replantation of left one. After 18 months, radiolucent lesions in the periapical areas of both maxillary central incisors had healed, and root apex development was noted with thickening of the walls in tooth #8.

  10. Locomotor Behavior of Chickens Anticipating Incline Walking

    Directory of Open Access Journals (Sweden)

    Chantal LeBlanc

    2018-01-01

    Full Text Available Keel bone damage (KBD is prevalent in hens raised for egg production, and ramps between different tiers in aviaries have potential to reduce the frequency of falls resulting in KBD. Effective use of ramps requires modulation of locomotion in anticipation of the incline. Inadequate adaptive locomotion may be one explanation why domestic layer hens (Gallus gallus domesticus exhibit high rates of KBD. To improve understanding of the capacity of hens to modulate their locomotion in anticipation of climbing, we measured the effects of incline angle upon the mechanics of the preparatory step before ascending a ramp. Because the energetic challenge of climbing increases with slope, we predicted that as angle of incline increased, birds during foot contact with the ground before starting to climb would increase their peak force and duration of contact and reduce variation in center of pressure (COP under their foot. We tested 20 female domestic chickens on ramp inclines at slopes of +0°, +40°, and +70° when birds were 17, 21, 26, 31, and 36 weeks of age. There were significantly higher vertical peak ground reaction forces in preparation at the steepest slope, and ground contact time increased significantly with each increase in ramp angle. Effects upon variation in COP were not apparent; likewise, effects of limb length, age, body mass were not significant. Our results reveal that domestic chickens are capable of modulating their locomotion in response to incline angle.

  11. Clinical evaluation of desensitizing treatment for incisor teeth affected by molar-incisor hypomineralization.

    Science.gov (United States)

    Ozgül, Betül Memiş; Saat, Sinem; Sönmez, Hayriye; Oz, Firdevs Tulga

    2013-01-01

    Sensitivity complaints are commonly observed in teeth affected by MIH (molar incisor hypomineralization). This study aimed to evaluate the hypersensitivity observed in MIH-affected teeth and the effect of desensitizing agents applied with and without ozone to incisors affected by MIH. The first part of the study included 120 teeth from 42 patients with MIH. These 42 patients included 33 children with 92 incisor teeth with a Vas score of > or = 30, and these 92 incisors were included in the second part of the study. The patients included in the second part were divided into three main groups and six subgroups. The main groups included the following: fluoride, CPP-ACP and CPP-ACP with fluoride. Each main group was divided into two subgroups: one with ozone use and one without ozone use. Girls exhibited significantly more sensitivity compared with boys (p 0.05). The results of this study revealed that gender is an important factor in the sensitivity of teeth with MLH. Desensitizing agents effectively reduced the hypersensitivity of teeth with MIH. CPP-ACP paste was found to be more effective, and ozone therapy prolonged the effect of CPP-ACP paste.

  12. Compound odontoma associated with impacted maxillary incisors.

    Science.gov (United States)

    Sreedharan, S; Krishnan, I S

    2012-01-01

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

  13. Compound odontoma associated with impacted maxillary incisors

    Directory of Open Access Journals (Sweden)

    S Sreedharan

    2012-01-01

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

  14. Three-dimensional volumetric display by inclined-plane scanning

    Science.gov (United States)

    Miyazaki, Daisuke; Eto, Takuma; Nishimura, Yasuhiro; Matsushita, Kenji

    2003-05-01

    A volumetric display system based on three-dimensional (3-D) scanning that uses an inclined two-dimensional (2-D) image is described. In the volumetric display system a 2-D display unit is placed obliquely in an imaging system into which a rotating mirror is inserted. When the mirror is rotated, the inclined 2-D image is moved laterally. A locus of the moving image can be observed by persistence of vision as a result of the high-speed rotation of the mirror. Inclined cross-sectional images of an object are displayed on the display unit in accordance with the position of the image plane to observe a 3-D image of the object by persistence of vision. Three-dimensional images formed by this display system satisfy all the criteria for stereoscopic vision. We constructed the volumetric display systems using a galvanometer mirror and a vector-scan display unit. In addition, we constructed a real-time 3-D measurement system based on a light section method. Measured 3-D images can be reconstructed in the 3-D display system in real time.

  15. Inclined nanoimprinting lithography for 3D nanopatterning

    International Nuclear Information System (INIS)

    Liu Zhan; Bucknall, David G; Allen, Mark G

    2011-01-01

    We report a non-conventional shear-force-driven nanofabrication approach, inclined nanoimprint lithography (INIL), for producing 3D nanostructures of varying heights on planar substrates in a single imprinting step. Such 3D nanostructures are fabricated by exploiting polymer anisotropic dewetting where the degree of anisotropy can be controlled by the magnitude of the inclination angle. The feature size is reduced from micron scale of the template to a resultant nanoscale pattern. The underlying INIL mechanism is investigated both experimentally and theoretically. The results indicate that the shear force generated at a non-zero inclination angle induced by the INIL apparatus essentially leads to asymmetry in the polymer flow direction ultimately resulting in 3D nanopatterns with different heights. INIL removes the requirements in conventional nanolithography of either utilizing 3D templates or using multiple lithographic steps. This technique enables various 3D nanoscale devices including angle-resolved photonic and plasmonic crystals to be fabricated.

  16. The influence of incline walking on joint mechanics.

    Science.gov (United States)

    Haggerty, Mason; Dickin, D Clark; Popp, Jennifer; Wang, Henry

    2014-04-01

    Walking is a popular form of exercise and is associated with many health benefits; however, frontal-plane knee joint loading brought about by a large internal knee-abduction moment and cyclic loading could lead to cartilage degeneration over time. Therefore, knee joint mechanics during an alternative walking exercise needs to be analyzed. The purpose of this study was to examine the lower-extremity joint mechanics in the frontal and sagittal planes during incline walking. Fifteen healthy males walked on a treadmill at five gradients (0%, 5%, 10%, 15%, and 20%) at 1.34m/s, and lower-extremity joint mechanics in the frontal and sagittal planes were quantified. The peak internal knee-abduction moment significantly decreased from the level walking condition at all gradients except 5%. Also, a negative relationship between the internal knee-abduction moment and the treadmill gradient was found to exist in 10% increments (0-10%, 5-15%, and 10-20%). The decrease in the internal knee-abduction moment during incline walking could have positive effects on knee joint health such as potentially reducing cartilage degeneration of the knee joint, reducing pain, and decreasing the rate of development of medial tibiofemoral osteoarthritis. This would be beneficial for a knee surgery patient, obese persons, and older adults who are using incline walking for rehabilitation and exercise protocols. Findings from the current study can provide guidance for the development of rehabilitation and exercise prescriptions incorporating incline walking. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Breakwaters with Vertical and Inclined Concrete Walls

    DEFF Research Database (Denmark)

    Burcharth, Hans Falk

    Following the PIANC PTC II working group on Analyses of Rubble Mound Breakwaters it was, in 1991, decided to form Working Group (WG) n° 28 on "Breakwaters with vertical and inclined concrete walls" The scope of the work was to achieve a better understanding of the overall safety aspects in the de......Following the PIANC PTC II working group on Analyses of Rubble Mound Breakwaters it was, in 1991, decided to form Working Group (WG) n° 28 on "Breakwaters with vertical and inclined concrete walls" The scope of the work was to achieve a better understanding of the overall safety aspects...

  18. Brain malformation in single median maxillary central incisor

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  19. Maxillary incisor root forms in orthodontic patients in Nairobi, Kenya ...

    African Journals Online (AJOL)

    Objective:To evaluate, radiographically, the root forms of maxillary incisors in a sample of patients seeking orthodontic treatment in Nairobi, Kenya. Design:A retrospective study of maxillary incisor root forms based on periapical radiographs. Setting: A private dental clinic in Nairobi, Kenya. Materials and Methods:The study ...

  20. Orthodontic intervention of an impacted upper left central incisor due ...

    African Journals Online (AJOL)

    A fixed orthodontic appliance was used to facilitate traction and correction of malalignement of the impacted upper left central incisor.Treatment outcome: Successful removal of the odontoma, full exposure of the crown of upper left central incisor and good alignment on the arch were achieved. Crowding on the upper and ...

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

    LENUS (Irish Health Repository)

    Daly, Dympna

    2009-04-01

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

  2. Measurement of the buccolingual inclination of teeth: manual technique vs 3-dimensional software.

    Science.gov (United States)

    Nouri, Mahtab; Abdi, Amir Hossein; Farzan, Arash; Mokhtarpour, Faraneh; Baghban, AliReza Akbarzadeh

    2014-10-01

    In this study, we aimed to measure the inclination of teeth on dental casts by a manual technique with the tooth inclination protractor (TIP; MBI, Newport, United Kingdom) and a newly designed 3-dimensional (3D) software program. The correlation of the 2 techniques was evaluated, and the reliability of each technique was assessed separately. This study was conducted on 36 dental casts of normal, well-aligned Class I occlusions; we assessed 432 teeth. All casts had a normal Class I occlusion. After determining the facial axis of the clinical crown and the facial axis points on the dental casts, we measured the inclinations of the incisors and posterior teeth up to the first molars in each dental arch relative to Andrews' occlusal plane and the posterior occlusal plane using the TIP. Moreover, the casts were scanned by a structured-light 3D scanner. The inclination of teeth relative to the occlusal plane was determined using the new software. To assess the reliability, measurements of all teeth from 15 casts were repeated twice by the 2 methods. Intraclass correlation coefficient and Dahlberg's formula were used for calculation of correlation and reliability. Overall, the 2 techniques were not significantly different in the measurements of the inclinations of the teeth in both jaws. The ranges of Dahlberg's formula were 3.1° to 5.8° for the maxilla and 3.3° to 5.9° for the mandible. The overall correlation of the 2 techniques according to the intraclass correlation coefficient was 0.91. For calculation of reliability, the intraclass correlation coefficients for the TIP and the 3D method were 0.73 and 0.82, respectively. The TIP and the 3D software showed a high correlation for measurement of the inclinations of maxillary and mandibular teeth relative to the occlusal plane. Also, the reproducibility of the measurements in each method was high. Copyright © 2014 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  3. Impacted incisors associated with supernumerary teeth treated with a modified Haas appliance.

    Science.gov (United States)

    Sant'Anna, Eduardo Franzotti; Marquezan, Mariana; Sant'Anna, Claudia Franzotti

    2012-12-01

    Tooth impaction involves factors such as lack of space in the alveolar process, trauma, ankylosis, and mechanical barriers such as abnormal frenum, supernumerary teeth, tumors, and local cysts. When impaction occurs in the anterior region, esthetics are compromised. This report describes the successful approach to treatment for a young boy who had 2 supernumerary teeth associated with impaction of the left central and lateral permanent incisors. Treatment consisted of extracting the supernumerary teeth and performing maxillary expansion with a modified Haas appliance to guide the left central incisor into its appropriate position. The teeth erupted spontaneously after maxillary expansion and an increase in space. A fixed edgewise appliance was placed incrementally to correct the maxillary anterior tooth positions and finish the treatment. Adequate esthetics and function were achieved. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  4. Effect of clear aligner therapy on the buccolingual inclination of mandibular canines and the intercanine distance.

    Science.gov (United States)

    Grünheid, Thorsten; Gaalaas, Sara; Hamdan, Hani; Larson, Brent E

    2016-01-01

    To compare the changes in buccolinugal inclination of mandibular canines and intercanine distance in patients treated with clear aligners to those treated with preadjusted edgewise appliances. The buccolingual inclination of mandibular canines and the intercanine distance were measured on pre- and posttreatment cone-beam computed tomograms of 30 patients who had been treated with clear aligners and 30 patients who had been treated with fixed preadjusted edgewise appliances. Differences between the aligner and fixed appliance groups and between pre- and posttreatment measurements were tested for statistical significance. In both groups, most of the mandibular canines had positive buccolingual inclinations (ie, their crowns were positioned lateral to their roots) both before and after treatment. While there was no difference between the groups pretreatment, the posttreatment buccolingual inclination was significantly greater in the aligner group. In the fixed appliance group, the canines became more upright with treatment, while the buccolingual inclination did not change significantly in the clear aligner group. The intercanine distance did not differ between the groups either before or after treatment. However, it increased significantly over the course of treatment in the aligner group, whereas it did not change significantly in the fixed appliance group. Orthodontic treatment with clear aligners tends to increase the mandibular intercanine distance with little change in inclination in contrast to treatment with fixed appliances, which leaves the intercanine distance unchanged but leads to more upright mandibular canines.

  5. Internally cooled V-shape inclined monochromator

    Czech Academy of Sciences Publication Activity Database

    Oberta, Peter; Áč, V.; Hrdý, Jaromír

    2008-01-01

    Roč. 15, - (2008), 8-11 ISSN 0909-0495 R&D Projects: GA AV ČR IAA100100716 Grant - others:VEGA(SK) 1/4134/07 Institutional research plan: CEZ:AV0Z10100522 Keywords : inclined monochromator * heat load * internal cooling Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.333, year: 2008

  6. A matter of chance, environment and inclination

    Indian Academy of Sciences (India)

    Lawrence

    Why did I opt for science subjects in school, and choose a career in science? Perhaps the best answer would be. 'Chance, Environment and Inclination'. Here I am, considered to be a professional woman scien- tist, working towards understanding the biology of the malaria parasite and the challenges put up by the same.

  7. Inclined test of nacelle wind lidar

    DEFF Research Database (Denmark)

    Courtney, Michael

    A nacelle wind lidar, placed at ground level, is tested by inclining the laser beams to bisect a measurement mast at a known distance and height. The horizontal wind speed reported by the lidar is compared to a reference cup anemometer mounted on the mast at the comparison height....

  8. Vehicle with inclinable caterpillar propulsion units

    International Nuclear Information System (INIS)

    Clar, G.

    1991-01-01

    This vehicle usable in hostile environment such nuclear industry has four propulsion units with a caterpillar track and two integrated motors: one for advancing the caterpillar track and the other for inclining the propulsion unit when overcoming obstacles. Each propulsion unit is easily replaceable because there are no mechanical parts in the body of the vehicle [fr

  9. Impacted permanent incisors associated with compound odontoma.

    Science.gov (United States)

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

    2015-01-12

    Odontomas are the most common odontogenic tumours of the maxillary bones, characterised by a slow growth and benign behaviour. They are usually small, asymptomatic and diagnosed after routine radiographic examination. The aim of this study was to report a case of a compound odontoma in the anterior maxilla of a 7-year-old girl, which was causing the impaction of the maxillary right central and lateral incisors, as well as the prolonged retention of the corresponding primary teeth. We also aimed to review the literature about these tumours, since they are not part of the dentist's day-to-day clinical practice. The clinical and radiographic features, the diagnosis and treatment of the case were discussed in this work. 2015 BMJ Publishing Group Ltd.

  10. Pulpal reactions in rat incisors to Caridex.

    Science.gov (United States)

    Wedenberg, C; Bornstein, R

    1990-12-01

    This study examined the in vivo effects of Caridex, a chemomechanical caries removal system, on rat pulpal tissue. Rat incisors were opened and the pulps exposed to Caridex or physiological saline and sealed with calcium hydroxide. After various time periods, teeth were extracted and examined by light microscopy. Histological evaluation revealed an almost identical response in both test and control teeth which consisted of a transient inflammatory reaction and a limited necrosis in adjacent pulp tissue. Within seven days, formation of hard tissue matrix was seen below the necrotic area and on pulpal walls. It was suggested that the high pH of Caridex may have contributed to the necrotizing effect of calcium hydroxide in adjacent pulp tissue and the formation of hard tissue matrix. Additionally, the solution is most probably bactericidal. The results suggest that the system can be used as a caries removal agent on humans without unfavourable side effects on the dental pulp.

  11. Diagnosis and treatment of molar incisor hypomineralization.

    Science.gov (United States)

    Mathu-Muju, Kavita; Wright, J Timothy

    2006-11-01

    Molar incisor hypomineralization (MIH) is a relatively common condition that varies in clinical severity and can result in early loss of the permanent 6-year molars. The etiology of MIH remains unclear, and the diagnosis can be confused with more generalized enamel defects such as those that occur in amelogenesis imperfecta. The management of MIH depends largely on the severity of the enamel defect. Degrees of hypomineralization can range from mild enamel opacities to enamel that readily abrades from the tooth as it emerges into the oral cavity. Usually, severely affected molars are extremely hypersensitive, prone to rapid caries development, and can be difficult to manage in young patients. The purpose of this article is to review approaches to diagnosing and treating MIH.

  12. Amoxicillin may cause molar incisor hypomineralization.

    Science.gov (United States)

    Laisi, S; Ess, A; Sahlberg, C; Arvio, P; Lukinmaa, P-L; Alaluusua, S

    2009-02-01

    The etiology of molar incisor hypomineralization (MIH) is unclear. Our hypothesis was that certain antibiotics cause MIH. We examined 141 schoolchildren for MIH and, from their medical files, recorded the use of antibiotics under the age of 4 yrs. MIH was found in 16.3% of children. MIH was more common among those children who had taken, during the first year of life, amoxicillin (OR=2.06; 95% CI, 1.01-4.17) or the rarely prescribed erythromycin (OR=4.14; 95% CI, 1.05-16.4), compared with children who had not received treatment. Mouse E18 teeth were cultured for 10 days with/without amoxicillin at concentrations of 100 microg/mL-4 mg/mL. Amoxicillin increased enamel but not dentin thickness. An altered pattern of amelogenesis may have interfered with mineralization. We conclude that the early use of amoxicillin is among the causative factors of MIH.

  13. STRATIFICATION TECHNIQUE IN MAXILLARY ANTERIOR INCISORS RESTORATION

    Directory of Open Access Journals (Sweden)

    Janet Kirilova

    2014-08-01

    Full Text Available Background: Because of their main characteristics: transparency, opalescence and color density, the tooth structures are extremely difficult to restore by means of completely inconspicuous restorations of the natural tooth tissue characteristics. The aim is to show successful aesthetic restoration of III Class dental lesions in upper incisors by means of high quality composites. Materials and method: A female patient visited the clinic being not satisfied with the esthetics of her front teeth. The intraoral examination showed previous restorations and carious lesions in 12, 11, 21, 22. After defining the tooth color a silicone key was made. The treatment was performed under anesthesia, the existing restorations were removed and the carious lesions in teeth 11, 12, 21, 22 were treated with restorations using Vanini edge preparation. The teeth were restored by means of stratification technique. After etching and rinsing, bonding was applied for 20 sec. and then polymerized. After fixing the silicone key enamel shade was applied and then dentine shades UD2, UD3, UD4 of 0.5mm thickness each. The polymerization was done layer by layer. Applied were 10 to 15 layers in total. The composite material was preheated in oven up to 55. Teeth 21 and 22 are restored with Enamel Plus HRi (Micerium. Results and Discussion: Excellent aesthetics is achieved with composite material. They have enamel and dentine shades and allow high quality aesthetics. The polishing is excellent in Enamel Plus HRi (Micerium which is typical for this type of composite. The result of the carious lesion treatment in this patient is real improvement of the dental appearance of her anterior incisors. Conclusion: Materials show excellent aesthetic results due to their characteristics and the stratification technique used.

  14. Maxillary lateral incisor agenesis; a retrospective cross-sectional study

    Directory of Open Access Journals (Sweden)

    Naji Ziad Arandi

    2018-04-01

    Full Text Available Objective: This study aims to estimate the prevalence of congenitally missing lateral incisors in a sample of 2662 dental patients in Palestine. Methods: A total of 2662 digital panoramic radiographs were retrospectively examined for the presence of congenitally missing permanent lateral incisors. The radiographs were obtained from the archival records of patients attending a local dental center at the city of Nablus in Palestine. Results: The prevalence of missing lateral incisors among the examined population (n = 2662 was found to be 1.91%. Unilateral agenesis accounted for 66.6% of the total cases that showed at least one missing lateral incisor. Around 79% of the unilateral cases were on the left side while 21% were on the right side. Bilateral agenesis accounted for 33.3% of 34 cases that had at least one congenitally missing permanent maxillary lateral incisor. Conclusion: The prevalence of missing maxillary lateral incisors in this study population was 1.91% which was within the range reported in different populations. Keywords: Tooth agenesis, Permanent maxillary lateral incisors, Retrospective, Prevalence

  15. Laser-Guided Autonomous Landing of a Quadrotor UAV on an Inclined Surface

    Science.gov (United States)

    Dougherty, John A.

    This thesis presents measurement, estimation, and control schemes to aid a quadrotor unmanned aerial vehicle (UAV) in landing on a flat, inclined surface without prior knowledge of the surface's inclination. The system uses a single CMOS camera and several inexpensive laser modules for onboard sensing to measure the distance to and orientation of a landing surface. A nonlinear least squares estimation scheme yields the altitude of the quadrotor and the normal vector defining the ground plane. This information is used to design a hybrid landing trajectory composed of a position tracking phase and an attitude tracking phase. A geometric nonlinear control system is used during each phase and ensures that the quadrotor's attitude is aligned to the inclination of the ground surface at touchdown. A quadrotor is developed from the ground up to test the in-flight measurement process and to execute landing trajectories on an inclined surface. Experimental results demonstrate the quadrotor's ability to accurately estimate altitude and ground plane orientation during flight, and numerical simulations of landing trajectories for various surface inclinations are validated by experimental results up to a maximum inclination of thirty degrees.

  16. Foreign body in a deciduous incisor: A radiological revelation

    Directory of Open Access Journals (Sweden)

    Lehl G

    2010-03-01

    Full Text Available A 6-year-old boy was brought to the dental department with a history of toothache in the anterior maxillary region. Intraoral examination revealed caries in the deciduous upper central and lateral incisor teeth. Radiological evaluation revealed the silhouette of a metallic paper clip in the pulp chamber of the deciduous right maxillary central incisor. The tooth was extracted as the permanent incisor was erupting below. Children often avoid informing their parents regarding such incidents due to fear of punishment.

  17. Fused upper central incisors: management of two clinical cases.

    Science.gov (United States)

    Sfasciotti, Gian Luca; Marini, Roberta; Bossù, Maurizio; Ierardo, Gaetano; Annibali, Susanna

    2011-03-01

    This paper reports the management of two clinical cases, in which the upper right central incisor was fused with a supernumerary tooth and the upper left central incisor was macrodontic. A radiographic examination revealed that the fused teeth had two separate roots. Hemisectioning of the fused teeth was performed, the supernumerary portion was extracted and the remaining part was reshaped to remove any sharp margins and to achieve a normal morphology. The macrodontic central incisors were not treated. At 12-months post-surgery there were no periodontal problems and no hypersensitivity. Orthodontic treatment was performed to appropriately align the maxillary teeth and to correct the malocclusion.

  18. [Central incisor and individualizing treatment of the smile due to orthodontics].

    Science.gov (United States)

    Rozencweig, Sophie; Muller, Christine

    2012-06-01

    The objectives of the orthodontic treatment that we provide are to re-establish functional occlusion and a harmonious facial appearance, taking the individual anatomic features of each patient into account as well the potential changes that will come with ageing. As a pre-treatment first step we analyze the position of the incisor teeth within the face. Next we pose several questions. Should we preserve a slight bi-maxillary protrusion or correct it? Should we decide to voluntarily maintain a slight supraclusion? When should we correct a gummy smile? What should we do about black holes? In this article we propose treatment approaches, illustrating them with clinical situations and focus on the critical role played by the central incisor in establishing smiles that are suitable for each patient, integrating them with the ageing patterns that we know the future will bring. © EDP Sciences, SFODF, 2012.

  19. Granular flow down a flexible inclined plane

    Directory of Open Access Journals (Sweden)

    Sonar Prasad

    2017-01-01

    Full Text Available Discrete and continuous systems are commonly studied individually, but seldom together. Indeed, granular flows are typically studied through flows over a rigid base. Here, we investigate the behaviour of granular flows over an inclined, flexible base. The flexible base is modeled as a rigid platform mounted on springs and has one degree of freedom. The base vibrations are introduced by the flow. We simulate such flows through a discrete element method and compare with experiments. We find that a flexible base increased the upper limit of the inclination up to which a steady flow is possible by at least 3 degrees. This stabilized zone may have important implications in applications such as conveyor belts and chutes.

  20. Granular flow down a flexible inclined plane

    Science.gov (United States)

    Sonar, Prasad; Sharma, Ishan; Singh, Jayant

    2017-06-01

    Discrete and continuous systems are commonly studied individually, but seldom together. Indeed, granular flows are typically studied through flows over a rigid base. Here, we investigate the behaviour of granular flows over an inclined, flexible base. The flexible base is modeled as a rigid platform mounted on springs and has one degree of freedom. The base vibrations are introduced by the flow. We simulate such flows through a discrete element method and compare with experiments. We find that a flexible base increased the upper limit of the inclination up to which a steady flow is possible by at least 3 degrees. This stabilized zone may have important implications in applications such as conveyor belts and chutes.

  1. Bubble streams rising beneath an inclined surface

    Science.gov (United States)

    Bird, James; Brasz, Frederik; Kim, Dayoung; Menesses, Mark; Belden, Jesse

    2017-11-01

    Bubbles released beneath a submerged inclined surface can tumble along the wall as they rise, dragging the surrounding fluid with them. This effect has recently regained attention as a method to mitigate biofouling in marine environment, such as a ship hull. It appears that the efficacy of this approach may be related to the velocity of the rising bubbles and the extent that they spread laterally as they rise. Yet, it is unclear how bubble stream rise velocity and lateral migration depend on bubble size, flow rate, and inclination angle. Here we perform systematic experiments to quantify these relationships for both individual bubble trajectories and ensemble average statistics. Research supported by the Office of Naval Research under Grant Number award N00014-16-1-3000.

  2. HIGH-INCLINATION ASTEROID FAMILIES V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the high-inclination asteroid families of Gil-Hutton (2006). A data set of 3652 high-inclination numbered asteroids was analyzed to search for...

  3. Non-dispersive traveling waves in inclined shallow water channels

    International Nuclear Information System (INIS)

    Didenkulova, Ira; Pelinovsky, Efim

    2009-01-01

    Existence of traveling waves propagating without internal reflection in inclined water channels of arbitrary slope is demonstrated. It is shown that traveling non-monochromatic waves exist in both linear and nonlinear shallow water theories in the case of a uniformly inclined channel with a parabolic cross-section. The properties of these waves are studied. It is shown that linear traveling waves should have a sign-variable shape. The amplitude of linear traveling waves in a channel satisfies the same Green's law, which is usually derived from the energy flux conservation for smoothly inhomogeneous media. Amplitudes of nonlinear traveling waves deviate from the linear Green's law, and the behavior of positive and negative amplitudes are different. Negative amplitude grows faster than positive amplitude in shallow water. The phase of nonlinear waves (travel time) is described well by the linear WKB approach. It is shown that nonlinear traveling waves of any amplitude always break near the shoreline if the boundary condition of the full absorption is applied.

  4. Tooth Wear Inclination in Great Ape Molars.

    Science.gov (United States)

    Knight-Sadler, Jordan; Fiorenza, Luca

    2017-01-01

    Primate dietary diversity is reflected in their dental morphology, with differences in size and shape of teeth. In particular, the tooth wear angle can provide insight into a species' ability to break down certain foods. To examine dietary and masticatory information, digitized polygon models of dental casts provide a basis for quantitative analysis of wear associated with tooth attrition. In this study, we analyze and compare the wear patterns of Pongo pygmaeus, Gorilla gorillagorilla and Pan troglodytes schweinfurthii lower molars, focusing on the degree of inclination of specific wear facets. The variation in wear angles appears to be indicative of jaw movements and the specific stresses imposed on food during mastication, reflecting thus the ecology of these species. Orangutans exhibit flatter wear angles, more typical of a diet consisting of hard and brittle foods, while gorillas show a wear pattern with a high degree of inclination, reflecting thus their more leafy diet. Chimpanzees, on the other hand, show intermediate inclinations, a pattern that could be related to their highly variable diet. This method is demonstrated to be a powerful tool for better understanding the relationship between food, mastication and tooth wear processes in living primates, and can be potentially used to reconstruct the diet of fossil species. © 2017 S. Karger AG, Basel.

  5. A jumping cylinder in an incline

    Science.gov (United States)

    Gomez, Raul W.; Hernandez, Jorge; Marquina, Vivianne

    2012-02-01

    The problem of a cylinder of mass m and radius r, with its center of mass out of the cylinder axis, rolling in an incline that makes an angle α respect to the horizontal is analyzed. The equation of motion is solved to obtain the site where the cylinder loses contact with the incline (jumps). Several simplifications are made: the analyzed system consists of an homogeneous disc with a one dimensional straight line of mass parallel to the disc axis at a distance d Styrofoam cylinder of radius r = 10.0 ± 0.05 cm, high h = 5.55 ± 0.05 cm and a mass m1 = 24.45 ± 0.05 g, to which a 9.50 ± 0.01 mm diameter and 5.10 ± 0.001 cm long brass road of mass m2 = 30.75 ± 0.05 g was imbibed parallel to the disc axis at a distance of 5.40 ± 0.05 cm from it. Then the disc rolls on a 3.20 m long wooden ramp inclined at 30 and 45 respect to the horizontal. To determine the jumping site, the movements were recorded with a high-speed video camera (Casio EX ZR100) at 400 frames per second. The experimental results agree well with the theoretical predictions.

  6. Precession of a Spinning Ball Rolling down an Inclined Plane

    Science.gov (United States)

    Cross, Rod

    2015-01-01

    A routine problem in an introductory physics course considers a rectangular block at rest on a plane inclined at angle a to the horizontal. In order for the block not to slide down the incline, the coefficient of sliding friction, µ, must be at least tan a. The situation is similar for the case of a ball rolling down an inclined plane. In order…

  7. Prevalence of isolated maxillary lateral incisor agenesis in Syrian adolescents.

    Science.gov (United States)

    Kabbani, Tamouh; Abdullah, Nagham; Rsheadat, Yasser; Hassan, Mohamed Ibrahim Abu

    2017-01-01

    This research is designed to obtain a better understanding and provide more insight of this phenomenon through evaluating the prevalence of congenital absence of maxillary lateral incisors in a Syrian population. The method involved clinical examination of 8000 school children with an equal number of males and females (age range 12-15 years) to identify students only affected by bilateral or unilateral congenital absence of maxillary lateral incisors. Agenesis was determined based on radiological evidence. The results of this study showed that the prevalence of isolated maxillary lateral incisors agenesis was 1.15%. In the sample studied, 66.3% of the patients were female and 33.7% were male (p agenesis in a Syrian population is within the average range with regard to other populations. A significant familial component to the etiology of maxillary lateral incisors agenesis was found.

  8. [Indirect bonded prosthesis. Use of an impacted central incisor].

    Science.gov (United States)

    Isaia, A M; Manfio, A P; Moraes, C J; Dutra, D A; Isaia, V G; Moncada, A C

    1990-01-01

    The authors presents a case about right central superior incisor impacted. After surgical remotion of the retain tooth, this was utilized like pontic in the confeccion of the indirect adhesive prosthesis for the patient.

  9. Unusual anatomy of maxillary central incisor with two roots

    Directory of Open Access Journals (Sweden)

    T S Ashwini Shivakumar

    2012-01-01

    Full Text Available Introduction: Knowledge of root canal morphology is essential for successful endodontic therapy. Failure to recognize unusual root canal anatomy may lead to unsuccessful endodontic treatment. Case Report: This case report describes the successful endodontic treatment of the maxillary central incisor with unusual anatomy of two roots and two root canals. A 23-year-old male patient was referred for dental consultation with discoloration of the maxillary right central incisor with periapical lesion, which revealed unusual anatomy of root on radiographic examination, and was confirmed upon exploration. Discussion: As described by Vertucci, the maxillary central incisor presents a single root and single root canal in 100% of the cases. However, few cases of maxillary central incisors with two canals were reported in the literature, most of which were associated with developmental anomalies like fusion, germination or dens invaginatus. Clinician should be aware of the unusual anatomical variations that should be detected by the different diagnostic resources available.

  10. Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization

    OpenAIRE

    Negre-Barber, A.; Montiel-Company, J. M.; Boronat-Catal?, M.; Catal?-Pizarro, M.; Almerich-Silla, J. M.

    2016-01-01

    Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Ka...

  11. The incidence of the dens invaginatus in the maxillary incisors

    International Nuclear Information System (INIS)

    Jin, Hae Yun; Lee, Sang Rae

    1980-01-01

    The purpose of this survey was to reveal a incidence of dens invaginatus in the maxillary incisor region. The material was 1671 sets of full mouth intraoral standard films, which was taken from the patients visiting for the routine check at the Infirmary of College of Dentistry, Kyung Hee University. The following results were obtained; 1. The incidence of dens invaginatus was 14.90 and that of slightly dilated dens invaginatus was 9.46%. 2. The incidence of dens invaginatus showed no difference between male and female. 3. Most of the dens invaginatus occurred in the maxillary lateral incisors (93.53%) and a few in the maxillary central incisors (6.46%) showed slight invagination. 4. Among the cases with dens invaginatus, over a half (53.41%) showed bilateral occurrence. 5. Comparatively rate cases, i. e. bilateral dens invaginatus of the maxillary central incisors, unilateral double dens invaginatus of the maxillary lateral incisor, and bilateral dens invaginatus of the maxillary lateral incisors, one side double and one side single, were reported.

  12. The incidence of the dens invaginatus in the maxillary incisors

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hae Yun; Lee, Sang Rae [Dept. of Dental Radiology, Division of Dentistry, Graduate School, Kyung Hee University, Seoul (Korea, Republic of)

    1980-11-15

    The purpose of this survey was to reveal a incidence of dens invaginatus in the maxillary incisor region. The material was 1671 sets of full mouth intraoral standard films, which was taken from the patients visiting for the routine check at the Infirmary of College of Dentistry, Kyung Hee University. The following results were obtained; 1. The incidence of dens invaginatus was 14.90 and that of slightly dilated dens invaginatus was 9.46%. 2. The incidence of dens invaginatus showed no difference between male and female. 3. Most of the dens invaginatus occurred in the maxillary lateral incisors (93.53%) and a few in the maxillary central incisors (6.46%) showed slight invagination. 4. Among the cases with dens invaginatus, over a half (53.41%) showed bilateral occurrence. 5. Comparatively rate cases, i. e. bilateral dens invaginatus of the maxillary central incisors, unilateral double dens invaginatus of the maxillary lateral incisor, and bilateral dens invaginatus of the maxillary lateral incisors, one side double and one side single, were reported.

  13. Effect of Fluoride and Simplified Adhesive Systems on the Bond Strength of Primary Molars and Incisors.

    Science.gov (United States)

    Firoozmand, Leily Macedo; Noleto, Lawanne Ellen Carvalho; Gomes, Isabella Azevedo; Bauer, José Roberto de Oliveira; Ferreira, Meire Coelho

    2015-01-01

    The aim of this study was evaluate in vitro the influence of simplified adhesive systems (etch-and-rinse and self-etching) and 1.23% acidulated phosphate fluoride (APF) on the microshear bond strength (μ-SBS) of composite resins on primary molars and incisors. Forty primary molars and forty incisors vestibular enamel was treated with either the self-etching Clearfil SE Bond (CSE, Kuraray) or etch-and-rinse Adper Single Bond 2 (SB2, 3M/ESPE) adhesive system. Each group was subdivided based on the prior treatment of the enamel with or without the topical application of 1.23% APF. Thereafter, matrices were positioned and filled with composite resin and light cured. After storage in distilled water at 37 ± 1°C for 24 h, the specimens were submitted to μ-SBS in a universal testing machine. Kruskal-Wallis and Mann-Whitney tests (p adhesive exerted no significant influence bond strength. In the inter-group analysis, however, significantly bond strength reduction was found for the incisors when CSE was employed with APF. Adhesive failure was the most common type of fracture. The bond strength was affected by the prior application of 1.23% APF and type of tooth.

  14. Deciduous molar hypomineralization and molar incisor hypomineralization.

    Science.gov (United States)

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

    2012-06-01

    This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life until young adulthood. This study focused on the relationship between Deciduous Molar Hypomineralization (DMH) and Molar Incisor Hypomineralization (MIH). First permanent molars develop during a period similar to that of second primary molars, with possible comparable risk factors for hypomineralization. Children with DMH have a greater risk of developing MIH. Clinical photographs of clean, moist teeth were taken with an intra-oral camera in 6,161 children (49.8% girls; mean age 74.3 mos, SD ± 5.8). First permanent molars and second primary molars were scored with respect to DMH or MIH. The prevalence of DMH and MIH was 9.0% and 8.7% at child level, and 4.0% and 5.4% at tooth level. The Odds Ratio for MIH based on DMH was 4.4 (95% CI, 3.1-6.4). The relationship between the occurrence of DMH and MIH suggests a shared cause and indicates that, clinically, DMH can be used as a predictor for MIH.

  15. Onset of molar incisor hypomineralization (MIH).

    Science.gov (United States)

    Fagrell, Tobias G; Salmon, Phil; Melin, Lisa; Norén, Jörgen G

    2013-01-01

    The etiological factors and timing of the onset of molar incisor hypomineralization (MIH) are still not clear. The aim of this study was to examine ground radial and sagittal sections from teeth diagnosed with MIH using light microscopy, polarized light microscopy and X-ray micro-computed tomography (XMCT) and to estimate the onset and timing of the MIH and to relate the hypomineralized enamel to the incremental lines. Thirteen extracted permanent first molars diagnosed MIH, were analyzed with light microscopy and XMCT. The hypomineralized areas were mainly located in the mesio-buccal cusps, starting at the enamel-dentin-junction and continuing towards the enamel surface. In a relative gray scale analysis the values decreased from the EDJ towards the enamel surface. The findings indicate that the ameloblasts in the hypomineralized enamel are capable of forming an enamel of normal thickness, but with a substantial reduction of their capacity for maturation of enamel. Chronologically, it is estimated that the timing of the disturbance is at a period during the first 6-7 months of age.

  16. Hydraulic shock waves in an inclined chute contraction

    Science.gov (United States)

    Jan, C.-D.; Chang, C.-J.

    2009-04-01

    A chute contraction is a common structure used in hydraulic engineering for typical reasons such as increase of bottom slope, transition from side channel intakes to tunnel spillways, reduction of chute width due to bridges, transition structures in flood diversion works, among others. One of the significant chute contractions in Taiwan is that used in the Yuanshantzu Flood Diversion Project of Keelung River. The diversion project is designed to divert flood water from upper Keelung River into East Sea with a capasity of 1,310 cubic meters per second for mitigating the flood damage of lower part of Keelung River basin in Northern Taiwan. An inclined chute contraction is used to connect Keelung River and a diversion turnel. The inlet and outlet works of the diversion project is located at Ruifang in the Taipei County of north Taiwan. The diameter of diversion tunnel is 12 meters and the total length of tunnel is 2,484 meters. The diversion project has been completed and successfully executed many times since 2004 to lower the water level of Keelung River in typhoon seasons for avioding flooding problems in the lower part of Keelung River basin. Flow in a chute contraction has complicated flow pattern due to the existence of shock waves in it. A simple and useful calculation procedure for the maximum height and its position of shock waves is essentially needed for the preliminary design stage of a chute contraction. Hydraulic shock waves in an inclined chute contraction were experimentally and numerically investigated in this study with the consideration of the effects of sidewall deflection angle, bottom inclination angle and Froude number of approaching flow. The flow pattern of hydraulic shock waves in a chute contraction was observed. The main issue of designing chute contraction is to estimate the height and position of maximum shock wave for the consideration of freeboards. Achieving this aim, the experimental data are adopted and analyzed for the shock angle

  17. Impact of slope inclination on salt accumulation

    Science.gov (United States)

    Nachshon, Uri

    2017-04-01

    Field measurements indicated on high variability in salt accumulation along natural and cultivated slopes, even for relatively homogeneous soil conditions. It was hypothesised that slope inclination has an impact on the location of salt accumulation along the slope. A set of laboratory experiments and numerical models were used to explore the impact of slope inclination on salt accumulation. It was shown, experimentally, that for conditions of saline water source at the lower boundary of the slope - salt accumulates in low concentrations and homogeneously along the entire slope, for moderate slopes. However, as inclination increases high salt concentrations were observed at the upper parts of the slope, leaving the lower parts of the slope relatively free of salt. The traditional flow and transport models did not predict the experimental observations as they indicated also for the moderate slopes on salt accumulation in the elevated parts of the slope, away of the saline water source. Consequently - a conceptual model was raised to explain the laboratory observations. It was suggested that the interactions between slope angle, evaporation rates, hydraulic conductivity of the medium and distribution of wetness along the slope affect the saline water flow path through the medium. This lead to preferential flow path close to the soil-atmosphere interface for the steep slopes, which leads to constant wash of the salts from the evaporation front upward towards the slope upper parts, whereas for the moderate slopes, flow path is below the soil-atmosphere interface, therefore salt that accumulates at the evaporation front is not being transported upward. Understanding of salt dynamics along slopes is important for agricultural and natural environments, as well as for civil engineering purposes. Better understanding of the salt transport processes along slopes will improve our ability to minimize and to cope with soil salinization processes. The laboratory experiments and

  18. Inclined solar chimney for power production

    Energy Technology Data Exchange (ETDEWEB)

    Panse, S.V., E-mail: sudhirpanse@yahoo.com [Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Jadhav, A.S.; Gudekar, A.S. [Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Joshi, J.B. [Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Homi Bhabha National Institute, Trombay, Mumbai 400 094 (India)

    2011-09-15

    Highlights: {yields} Solar energy harnessing using inclined face of high mountains as solar chimney. {yields} Solar chimneys with structural stability, ease of construction and lower cost. {yields} Mathematical model developed, using complete (mechanical and thermal) energy balance. {yields} Can harness wind power also, as wind velocities at mountain top add to power output. {yields} Air temperature and velocity increase, as air rises in inclined chimney. - Abstract: The present concept of solar chimney is a tall vertical chimney constructed at the center of a large area, which is the collector. This creates questions about stability and economic viability of the chimney and also demands elaborate engineering techniques for constructing a tall chimney. We suggest geometry of 'Inclined Solar Chimney' (ISC), which is constructed along the face of a high rising mountain, on which maximum solar insolation is incident throughout the year. The chimney and the collector get merged here. This makes the structure stable, cost effective and easy for construction. A mathematical model has been developed considering the total energy balance. It predicts the temperature and velocity and kinetic power of the emerging air draft for some chosen values of other parameters. The model also shows the proportion in which absorbed solar energy is divided into different forms, and hence predicts the dependence of kinetic of emerging air draft upon dimensions of the chimney and properties of materials used. Further, it is shown that external winds enhance the kinetic power of the emerging air. Thus ISC can also harness the wind energy, available at the top of the mountain.

  19. Agenesis of maxillary lateral incisors and associated dental anomalies.

    Science.gov (United States)

    Garib, Daniela Gamba; Alencar, Bárbara Maria; Lauris, José Roberto Pereira; Baccetti, Tiziano

    2010-06-01

    The objectives of this study were to evaluate the prevalence of dental anomalies in patients with agenesis of maxillary lateral incisors and to compare the findings with the prevalence of these anomalies in the general population. A sample of 126 patients, aged 7 to 35 years, with agenesis of at least 1 maxillary lateral incisor was selected. Panoramic and periapical radiographs and dental casts were used to analyze other associated dental anomalies, including agenesis of other permanent teeth, ectopia of unerupted permanent teeth, microdontia of maxillary lateral incisors, and supernumerary teeth. The occurrence of these anomalies was compared with prevalence data previously reported for the general population. Statistical testing was performed with the chi-square test (P <0.05) and the odds ratio. Patients with maxillary lateral incisor agenesis had a significantly increased prevalence rate of permanent tooth agenesis (18.2%), excluding the third molars. The occurrence of third-molar agenesis in a subgroup aged 14 years or older (n = 76) was 35.5%. The frequencies of maxillary second premolar agenesis (10.3%), mandibular second premolar agenesis (7.9%), microdontia of maxillary lateral incisors (38.8%), and distoangulation of mandibular second premolars (3.9%) were significantly increased in our sample compared with the general population. In a subgroup of patients aged 10 years or older (n = 115), the prevalence of palatally displaced canines was elevated (5.2%). The prevalences of mesioangulation of mandibular second molars and supernumerary teeth were not higher in the sample. Permanent tooth agenesis, maxillary lateral incisor microdontia, palatally displaced canines, and distoangulation of mandibular second premolars are frequently associated with maxillary lateral incisor agenesis, providing additional evidence of a genetic interrelationship in the causes of these dental anomalies. 2010 American Association of Orthodontists. Published by Mosby, Inc. All

  20. Dense, layered, inclined flows of spheres

    Science.gov (United States)

    Jenkins, James T.; Larcher, Michele

    2017-12-01

    We consider dense, inclined flows of spheres in which the particles translate in layers, whose existence may be promoted by the presence of a rigid base and/or sidewalls. We imagine that in such flows a sphere of a layer is forced up the back of a sphere of the layer below, lifting a column of spheres above it, and then falls down the front of the lower sphere, until it bumps against the preceding sphere of the lower layer. We calculate the forces and rate of momentum transfer associated with this process of rub, lift, fall, and bump and determine a relation between the ratio of shear stress to normal stress and the rate of strain that may be integrated to obtain the velocity profile. The fall of a sphere and that of the column above it results in a linear increase in the magnitude of the velocity fluctuations with distance from the base of the flow. We compare the predictions of the model with measured profiles of velocity and granular temperature in several different dense, inclined flows.

  1. Global burden of molar incisor hypomineralization.

    Science.gov (United States)

    Schwendicke, Falk; Elhennawy, Karim; Reda, Seif; Bekes, Katrin; Manton, David J; Krois, Joachim

    2018-01-01

    We aimed to systematically review and meta-analyze the global, super-regional, regional and national prevalence of molar-incisor-hypomineralization (MIH) and to determine the numbers of prevalent and incident cases on different spatial scales. The review was registered (PROSPERO CRD42017063842). Five electronic databases (Medline, EMBASE, LILACS, Web of Science, Google Scholar) were searched systematically. Observational studies on the prevalence of MIH were included and the prevalence on different spatial scales (global, super-regional, regional, national) synthesized using random-effects meta-analyses. The prevalence was then regressed on a large set of methodological, socioeconomic and environmental variables to estimate the global burden (incident and prevalent cases) of MIH. Of 2239 identified studies, 99 studies on 113,144 participants from 43 countries were included. The meta-analysis yielded a mean (95% CI) prevalence of 13.1% (11.8-14.5%), with significant differences between super-regions, regions and countries. The number of prevalent cases in 2015 was estimated at 878 (791-971) million people, while the number of incident cases in 2016 was 17.5 (15.8-19.4) million. Of these, 27.4% (23.5-31.7%) (in mean, 240 million prevalent and 4.8 million incident cases, respectively) were or will be in need of therapy due to pain, hypersensitivity or posteruptive breakdown. Heavily populated countries contribute significantly to the burden of prevalent cases, while growing countries like India, but also Pakistan or Indonesia rank first with respect to the number of incident cases. MIH is highly prevalent across the globe. Certain (mainly low- and middle income) countries shoulder the majority of this burden. Clinical significance The consistently high prevalence and the large proportion of cases in need of care should be considered by both clinicians in their daily practice and healthcare planners and policy makers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Critical heat flux during natural convective boiling in inclined tubes submerged in saturated liquids

    International Nuclear Information System (INIS)

    Liu Zhenhua; Yang Ronghua

    2005-01-01

    An experimental study was carried out to improve and expand understanding of boiling phenomena and the critical heat flux (CHF) during natural convective boiling in uniformly heated inclined tubes submerged in a pool of saturated liquids under atmospheric pressure. The test conditions were as follows: inter diameters of the test tubes ranged from 0.9 to 8.0 mm; heated lengths ranged from 100 to 400 mm, and inclination angles varied from 30 o to vertical position. The test fluids were water and R-11. The experimental results showed that the CHF decreases with the increasing ratio of the tube length to the tube diameter, and with the reducing of the inclination angle. A semi-theoretical correlation, which originally used for the CHF during natural convective boiling in vertical tubes, was modified to predict the CHF occurs in the inclined tubes. The modified correlation agreed reasonably well with the present experimental data and other CHF data for narrow inclined annular tubes

  3. Finite element analysis of equine incisor teeth. Part 2: investigation of stresses and strain energy densities in the periodontal ligament and surrounding bone during tooth movement.

    Science.gov (United States)

    Schrock, P; Lüpke, M; Seifert, H; Staszyk, C

    2013-12-01

    This study investigated the hypothetical contribution of biomechanical loading to the onset of equine odontoclastic tooth resorption and hypercementosis (EOTRH) and to elucidate the physiological age-related positional changes of the equine incisors. Based on high resolution micro-computed tomography (μCT) datasets, 3-dimensional models of entire incisor arcades and the canine teeth were constructed representing a young and an old incisor dentition. Special attention was paid to constructing an anatomically correct model of the periodontal ligament (PDL). Using previously determined Young's moduli for the equine incisor PDL, finite element (FE) analysis was performed. Resulting strains, stresses and strain energy densities (SEDs), as well as the resulting regions of tension and compression within the PDL and the surrounding bone were investigated during occlusion. The results showed a distinct distribution pattern of high stresses and corresponding SEDs in the PDL and bone. Due to the tooth movement, peaks of SEDs were obtained in the PDL as well as in the bone on the labial and palatal/lingual sides of the alveolar crest. At the root, highest SEDs were detected in the PDL on the palatal/lingual side slightly occlusal of the root tip. This distribution pattern of high SEDs within the PDL coincides with the position of initial resorptive lesions in EOTRH affected teeth. The position of high SEDs in the bone can explain the typical age-related alteration of shape and angulation of equine incisors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Visualization of the impact of water drops on a hot surface: effect of drop velocity and surface inclination

    Energy Technology Data Exchange (ETDEWEB)

    Celata, Gian Piero; Mariani, Andrea; Zummo, Giuseppe [ENEA, Institute of Thermal-Fluid Dynamics, S. Maria di Galeria (Rome) (Italy); Cumo, Maurizio [Universita di Roma ' ' La Sapienza' ' , Rome (Italy)

    2006-08-15

    The behaviour of one drop impinging on a hot surface by varying the surface temperature, the drop velocity and the position of the surface (horizontal and a inclined 45 ) both at a temperature below and above the Leidenfrost temperature has been experimentally evaluated, estimating the temperature at which the drop rebounds. A large influence on the drop velocity has been evidenced. The inclination of the surface decreases the critical value of the temperature above which the surface is not rewetted. (orig.)

  5. Relationship between the shape of the upper central incisors and the facial contour in dental students. Lima. Peru.

    Directory of Open Access Journals (Sweden)

    Miguel Cabello

    2015-06-01

    Full Text Available Determine the relationship between the shape of the face and the shape of the upper right central incisor according to “The law of harmony” proposed by Williams. Materials and methods: This was an observational, analytic and cross-sectional study. A sample of 124 subjects, male and female students between 17 and 28 years old, was selected for the research. Their facial biotype and the shape of their upper right central incisor were determined by means of direct and photographic methods. Height and facial width were clinically evaluated using the direct method, and the proximal contours of the incisors were evaluated using a Vernier digital caliper. Images were downloaded to a computer and analyzed by means of the photographic method using Adobe Photoshop 5.0. Results: The relationship between the shape of the face and the shape of the incisor was positive in 43.5% of the sample (p=0.006 in the direct method. In the photographic method, the relationship between the shape of the face and the shape of the incisor was positive in 41.1% of the sample (p=0.037. The most frequent facial biotype in the direct and photographic methods was the dolichofacial with 61.3% and 71% respectively. The most frequent shape of the tooth with the direct and photographic methods was the ovoid with 55.6% and 51.6% respectively. Conclusion: Results do not confirm “The law of harmony” proposed by Williams, therefore when choosing the most suitable anterior tooth, experience and criteria of the dentist as well as the opinion of the patient should be taken in account in order to achieve a good aesthetic result.

  6. Molar-incisor hypomineralization: Therapeutic challenge to paediatric dentistry practice

    Directory of Open Access Journals (Sweden)

    Stojković Branislava

    2017-01-01

    Full Text Available Introduction: Molar incisor hypomineralization indicates the appearance of enamel hypomineralization of systemic origin which occurs in 1-4 first permanent molars, which is often accompanied by changes on permanent incisors. Variations in clinical manifestation, together with commonly present asymmetry, are the reason for large variations in the needs for therapeutic treatment of these structural enamel defects. Case study: Two patients with diagnosed molar incisor hypomineralization are shown. The first patient, a six-year-old girl, with diagnosed mild clinical form, visited the dentist immediately after the eruption of the first permanent molars. Early diagnosis and timely application of preventive-profilactic measures, together with mild clinical form, are the reason for prevention of dental caries and further spreading of posteruptive enamel breakdown on affected first molars. Unlike the first one, the second patient, a 7,5-year-old girl had the diagnosis of moderate molar incisor hypomineralization. She developed dental caries on tooth 46 as well as complication in dental caries on tooth 36 which was extracted soon after the eruption. Conclusion: Early diagnosis and the severity of clinical appearance are the most important factors which determine therapeutic outcome of the treatment of molar incisor hypomineralization.

  7. On liquid films on an inclined plate

    KAUST Repository

    BENILOV, E. S.

    2010-08-18

    This paper examines two related problems from liquid-film theory. Firstly, a steady-state flow of a liquid film down a pre-wetted plate is considered, in which there is a precursor film in front of the main film. Assuming the former to be thin, a full asymptotic description of the problem is developed and simple analytical estimates for the extent and depth of the precursor film\\'s influence on the main film are provided. Secondly, the so-called drag-out problem is considered, where an inclined plate is withdrawn from a pool of liquid. Using a combination of numerical and asymptotic means, the parameter range where the classical Landau-Levich-Wilson solution is not unique is determined. © 2010 Cambridge University Press.

  8. Granular flow over inclined channels with constrictions

    Science.gov (United States)

    Tunuguntla, Deepak; Weinhart, Thomas; Thornton, Anthony; Bokhove, Onno

    2013-04-01

    Study of granular flows down inclined channels is essential in understanding the dynamics of natural grain flows like landslides and snow avalanches. As a stepping stone, dry granular flow over an inclined channel with a localised constriction is investigated using both continuum methods and particle simulations. Initially, depth-averaged equations of motion (Savage & Hutter 1989) containing an unknown friction law are considered. The shallow-layer model for granular flows is closed with a friction law obtained from particle simulations of steady flows (Weinhart et al. 2012) undertaken in the open source package Mercury DPM (Mercury 2010). The closed two-dimensional (2D) shallow-layer model is then width-averaged to obtain a novel one-dimensional (1D) model which is an extension of the one for water flows through contraction (Akers & Bokhove 2008). Different flow states are predicted by this novel one-dimensional theory. Flow regimes with distinct flow states are determined as a function of upstream channel Froude number, F, and channel width ratio, Bc. The latter being the ratio of the channel exit width and upstream channel width. Existence of multiple steady states is predicted in a certain regime of F - Bc parameter plane which is in agreement with experiments previously undertaken by (Akers & Bokhove 2008) and for granular flows (Vreman et al. 2007). Furthermore, the 1D model is verified by solving the 2D shallow granular equations using an open source discontinuous Galerkin finite element package hpGEM (Pesch et al. 2007). For supercritical flows i.e. F > 1 the 1D asymptotics holds although the two-dimensional oblique granular jumps largely vary across the converging channel. This computationally efficient closed 1D model is validated by comparing it to the computationally more expensiveaa three-dimensional particle simulations. Finally, we aim to present a quasi-steady particle simulation of inclined flow through two rectangular blocks separated by a gap

  9. Postretention mandibular incisor stability after premolar serial extractions.

    Science.gov (United States)

    Woodside, D G; Rossouw, P E; Shearer, D

    1999-09-01

    The purpose of this study was to evaluate the mandibular incisor alignment in serial extraction cases, using the longitudinal dental cast records of the Burlington Growth Center as a control sample. Various parameters were investigated and the statistical differences determined between the treated and untreated groups. The results were also compared with data from serial extraction groups that subsequently had orthodontic treatment. Untreated subjects and subjects treated only with serial extractions showed similar longitudinal changes. However, the extraction group that also received orthodontic treatment appeared to show more lower incisor crowding long-term. No predictors for stability of clinical significance could be determined. Mechanotherapy influences the craniofacial and dentoalveolar dimensions, which appear to cause more long-term lower incisor crowding.

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

    Directory of Open Access Journals (Sweden)

    Khalid H. Zawawi

    2014-01-01

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

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

    Science.gov (United States)

    Zawawi, Khalid H

    2014-01-01

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

  12. Orthodontic management of impacted central incisor: A clinical challenge

    Directory of Open Access Journals (Sweden)

    Amit Kumar Khera

    2017-01-01

    Full Text Available Multiple treatment options are available for patients who have impacted incisor. This paper shows a case in which orthodontic as well as surgical considerations in 10-year-old female child were presented in the management of impacted central incisor. The orthodontic treatment plan included three steps – creation of space, exposure of crown, and forced eruption. A unique and innovative technique for orthodontic traction (0.017 × 0.025 TMA wire with palatal extension was employed to move the maxillary incisor into arch, with minimum injury to neighboring soft tissue. After the successful management of impacted teeth, it is very important to periodically review the periodontal condition and stability.

  13. On the Etiology of Molar-Incisor Hypomineralization.

    Science.gov (United States)

    Vieira, Alexandre R; Kup, Elaine

    Molar-incisor hypomineralization (MIH) is a condition that is defined based on its peculiar clinical presentation. Reports on the etiology of the condition and possible risk factors are inconclusive and the original suggestion that MIH is an idiopathic condition is often cited. Our group was the first to suggest MIH has a genetic component that involves genetic variation in genes expressed during dental enamel formation. In this report, we provide a rationale to explain the preferential affection of molars and incisors. We suggest that MIH is a genetic condition based on its prevalence, which varies depending on the geographic location, and the evidence that on occasion second primary molars, permanent canines, and premolars can show signs of hypomineralization of enamel when molars and incisors are affected. © 2016 S. Karger AG, Basel.

  14. Inclined Buildings – Some Reasons and Solutions

    Science.gov (United States)

    Kijanka, Małgorzata; Kowalska, Magdalena

    2017-10-01

    To straighten a leaning building is never easy. There are no standard solutions. On the other hand, there are several, usually historical, leaning structures which have not been rectified, mostly because in the current shape they are a touristic attraction - the best example being the famous Leaning Tower of Pisa. This does not mean however that inclination of load bearing walls can be ignored. Even though in some cases the problem can be treated in terms of serviceability limit states (the deformation is only decreasing the comfort of ‘normal use’ of the building), in the other – it may be a signal of the forthcoming structural failure. The situation must always be treated individually – if the problem concerns a residential building, then cracks on the walls, not-opening doors or tilted ceilings, which often coincide with the leaning of the external walls, are always the reason of worry and such a building needs to be straightened. The reasons of the problem lie usually in uneven settlement of the ground, which in turn, may be caused by various problems, such as the presence of too soft, too weak, unconsolidated or expansive soils under the building, varying groundwater table, mining activity etc. Solving of the problem by just straightening the building is often not enough. To prevent further deformations a detailed analysis of the possible causes is necessary. Sometimes it may be helpful to review similar cases. The paper contains a general overview of selected inclined buildings: starting with the well-known historical examples and ending with individual houses from the Region of Silesia. Since the problem of instability mostly affects structures with critical height to width ratio, tall and narrow structures (towers) are dominating in the work. The aim of the study was to describe the reasons of the problems and present solutions that have been successfully applied and can be also useful to engineers and designers to prevent similar situations.

  15. Impinging Water Droplets on Inclined Glass Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Armijo, Kenneth Miguel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lance, Blake [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ho, Clifford K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    Multiphase computational models and tests of falling water droplets on inclined glass surfaces were developed to investigate the physics of impingement and potential of these droplets to self-clean glass surfaces for photovoltaic modules and heliostats. A multiphase volume-of-fluid model was developed in ANSYS Fluent to simulate the impinging droplets. The simulations considered different droplet sizes (1 mm and 3 mm), tilt angles (0°, 10°, and 45°), droplet velocities (1 m/s and 3 m/s), and wetting characteristics (wetting=47° contact angle and non-wetting = 93° contact angle). Results showed that the spread factor (maximum droplet diameter during impact divided by the initial droplet diameter) decreased with increasing inclination angle due to the reduced normal force on the surface. The hydrophilic surface yielded greater spread factors than the hydrophobic surface in all cases. With regard to impact forces, the greater surface tilt angles yielded lower normal forces, but higher shear forces. Experiments showed that the experimentally observed spread factor (maximum droplet diameter during impact divided by the initial droplet diameter) was significantly larger than the simulated spread factor. Observed spread factors were on the order of 5 - 6 for droplet velocities of ~3 m/s, whereas the simulated spread factors were on the order of 2. Droplets were observed to be mobile following impact only for the cases with 45° tilt angle, which matched the simulations. An interesting phenomenon that was observed was that shortly after being released from the nozzle, the water droplet oscillated (like a trampoline) due to the "snapback" caused by the surface tension of the water droplet being released from the nozzle. This oscillation impacted the velocity immediately after the release. Future work should evaluate the impact of parameters such as tilt angle and surface wettability on the impact of particle/soiling uptake and removal to investigate ways that

  16. Ectopic eruption of maxillary central incisor through abnormally thickened labial frenum: An unusual presentation

    Directory of Open Access Journals (Sweden)

    Neeraj Gugnani

    2017-01-01

    Full Text Available Ectopic eruption is a deviation from the normal eruption pattern, making the tooth erupt out of its normal position, and possibly causing resorption of adjacent primary teeth. A wide range of etiological factors may be responsible for ectopic eruption of the teeth, so their management depends on the correction of the established etiological factor. The present case report describes an unusual case of ectopically erupted central incisor encased within an abnormally thickened labial frenum, which was treated by orthodontic repositioning of the ectopically erupting tooth after frenectomy.

  17. Psychosocial Determinants of Romantic Inclination Among Indian Youth

    Directory of Open Access Journals (Sweden)

    D. Barani Ganth

    2017-10-01

    Full Text Available The present study was conducted with the aim of understanding the psychosocial determinants of romantic inclination among youth in India. We involved 779 student participants from a large central university in south India in the age range of 18-24 years. The participants filled measures on romantic inclination, personality, attachment style, interpersonal attraction, and social influence on romantic relationship in addition to a questionnaire on demographic information and relationship history. Analysis of the data revealed that males showed higher level of romantic inclination than females. Those who had current/past involvement in a romantic relationship (Lovers showed higher levels of romantic inclination than those who had never involved in a romantic relationship (Non-lovers. Parents’ type of marriage (Love/arranged, close fiends’ involvement in romantic relationship too had a discriminatory role in romantic inclination. Romantic inclination was significantly related to personality factors, attachment style, media and peer influences on romantic relationships and interpersonal attraction. Extraversion, openness to experience, agreeableness, media influence, peer influence, secure attachment and physical attraction emerged as significant predictors of romantic inclination in a regression model. Structural Equations Modeling (SEM indicated that personality, attachment style and interpersonal attraction had a significant influence on romantic inclination mediated by both media and peer influences. Romantic inclination in turn significantly predicted romantic relationship status.

  18. Impact of flow inclination on downwind turbine loads and power

    Science.gov (United States)

    Kress, C.; Chokani, N.; Abhari, R. S.; Hashimoto, T.; Watanabe, M.; Sano, T.; Saeki, M.

    2016-09-01

    Wind turbines frequently operate under situations of pronounced flow inclinations, such as in complex terrain. In the present work the performance and rotor thrust of downwind and upwind turbines in upward and downward flow inclinations are experimentally investigated. In an upward flow inclination of +13°, downwind turbines are shown to have a 29% larger power output than a corresponding upwind turbine, whereas the relative increase in rotor thrust is only 9%. Furthermore, it is also shown that the performance of downwind turbines is less sensitive to changes in the flow inclination, as the upstream nacelle on downwind turbines beneficially redirects and accelerates the flow around the nacelle into the rotor plane.

  19. The Gothic arch (needle point) tracing and condylar inclination.

    Science.gov (United States)

    el-Gheriani, A S; Winstanley, R B

    1987-11-01

    The records of 11 patients referred for treatment of TMJ disorders were used to compare condylar inclination found by drawing a tangent and by using a mathematic technique. Needle point tracing angles were also measured for the same patients and were compared with the condylar inclination. It can be concluded that (1) the mathematic technique outlined records a more accurate condylar angulation, and (2) there is a great variation in condylar inclination values between patients and between left and right sides of the same patient, and (3) there is no direct relationship between condylar inclination and the needle point tracing angle.

  20. Early Miocene catarrhine dietary behaviour: the influence of the Red Queen Effect on incisor shape and curvature.

    Science.gov (United States)

    Deane, Andrew S

    2009-03-01

    The early Miocene catarrhine fossil record of East Africa represents a diverse and extensive adaptive radiation. It is well accepted that these taxa encompass a dietary range similar to extant hominoids, in addition to some potentially novel dietary behaviour. There have been numerous attempts to infer diet for these taxa from patterns of dental allometry and incisor and molar microwear, however, morphometric analyses until now have been restricted to the post-canine dentition. It has already been demonstrated that given the key functional role of the incisors in pre-processing food items prior to mastication, there is a positive correlation between diet and incisal curvature (Deane, A.S., Kremer, E.P., Begun, D.R., 2005. A new approach to quantifying anatomical curvatures using High Resolution Polynomial Curve Fitting (HR-PCF). Am. J. Phys. Anthropol. 128(3), 630-638.; Deane, A.S., 2007. Inferring dietary behaviour for Miocene hominoids: A high-resolution morphometric approach to incisal crown curvature. Ph.D. Dissertation. The University of Toronto.). This study seeks to re-examine existing dietary hypotheses for large-bodied early Miocene fossil catarrhines by contrasting the incisal curvature for these taxa with comparative models derived from prior studies of the correlation between extant hominoid incisor curvature and feeding behaviour. Incisor curvature was quantified for 78 fossil incisors representing seven genera, and the results confirm that early Miocene fossil catarrhines represent a dietary continuum ranging from more folivorous (i.e., Rangwapithecus) to more frugivorous (i.e., Proconsul) diets, as well as novel dietary behaviours that are potentially similar to extant ceboids (i.e., Afropithecus). Additionally, early Miocene fossil catarrhine incisors are less curved than extant hominoid incisors, indicating a general pattern of increasing mesio-distal and labial curvature through time. This pattern of morphological shifting is consistent with the

  1. Multidisciplinary treatment of a fractured maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Neela

    2017-01-01

    Full Text Available Subgingivally fractured incisors are still a challenge to treat. Restoration of severely damaged teeth requires careful attention and comprehensive preplanned treatment. Here, a patient who had traumatic injury to the upper left central incisor which led to an oblique fracture involving enamel, dental and extending into the root below the gingival margin was saved from extraction by accelerated forced eruption of a root portion, allowing placement of crown, and eliminating the need for a fixed partial denture. A tooth otherwise would have gone for extraction routinely was thus saved and restored through a multidisciplinary approach by a combined orthodontic, periodontal and endodontic treatment.

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

    LENUS (Irish Health Repository)

    McNamara, T G

    1996-08-01

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

  3. Revealing the inclined circumstellar disk in the UX Ori system KK Ophiuchi

    Science.gov (United States)

    Kreplin, A.; Weigelt, G.; Kraus, S.; Grinin, V.; Hofmann, K.-H.; Kishimoto, M.; Schertl, D.; Tambovtseva, L.; Clausse, J.-M.; Massi, F.; Perraut, K.; Stee, Ph.

    2013-07-01

    We study the inner sub-AU region of the circumstellar environment of the UX Ori type star KK Oph with near-infrared VLTI/AMBER interferometry. We are particularly interested in the inclination of the star-disk system, and we will use this information to test the current standard picture for UX Ori stars. We recorded spectrally dispersed (R˜35) interferograms in the near-infrared H and K bands with the VLTI/AMBER instrument. The derived visibilities, closure phases and the SED of KK Oph were compared with two-dimensional geometric and radiative transfer models (RADMC). We obtained visibilities at four different position angles. Using two-dimensional geometric models, we derive an axis ratio ˜3.0 corresponding to an inclination of ˜70 degree. A fitted inclined ring model leads to a ring radius of 2.8 ± 0.2 mas, corresponding to 0.44 ± 0.03 AU at a distance of 160 pc, which is larger than the dust sublimation radius of ˜0.1 AU predicted for a dust sublimation temperature of 1500 K. Our derived two-dimensional RADMC model consists of a circumstellar disk with an inclination angle of ˜70 degree and an additional dust envelope. The finding of an ˜70 degree inclined disk around KK Oph is consistent with the prediction that UX Ori objects are seen under large inclination angles, and orbiting clouds in the line of sight cause the observed variability. Furthermore, our results suggest that the orbit of the companion KK Oph B and the disk plane are coplanar.

  4. Revealing the inclined circumstellar disk in the UX Orionis system KK Ophiuchi

    Science.gov (United States)

    Kreplin, A.; Weigelt, G.; Kraus, S.; Grinin, V.; Hofmann, K.-H.; Kishimoto, M.; Schertl, D.; Tambovtseva, L.; Clausse, J.-M.; Massi, F.; Perraut, K.; Stee, Ph.

    2013-03-01

    Aims: We study the inner sub-AU region of the circumstellar environment of the UX Ori-type star KK Oph with near-infrared VLTI/AMBER interferometry. We are particularly interested in the inclination of the star-disk system, and we use this information to test the current standard picture for UX Ori stars. Methods: We recorded spectrally dispersed (R ~ 35) interferograms in the near-infrared H and K bands with the VLTI/AMBER instrument. The derived visibilities, closure phases, and the spectral energy distribution of KK Oph were compared with two-dimensional geometric and radiative transfer models (RADMC). Results: We obtained visibilities at four different position angles. Using two-dimensional geometric models, we derive an axis ratio ~3.0 corresponding to an inclination of ~70°. A fitted inclined ring model leads to a ring radius of 2.8 ± 0.2 mas, corresponding to 0.44 ± 0.03 AU at a distance of 160 pc, which is larger than the dust sublimation radius of ~0.1 AU predicted for a dust sublimation temperature of 1500 K. Our derived two-dimensional RADMC model consists of a circumstellar disk with an inclination angle of ~70° and an additional dust envelope. Conclusions: The finding of an ~70° inclined disk around KK Oph is consistent with the prediction that UX Ori objects are seen under large inclination angles, and orbiting clouds in the line of sight cause the observed variability. Furthermore, our results suggest that the orbit of the companion KK Oph B and the disk plane are coplanar. Based on observations made with ESO telescopes at Paranal Observatory under program ID: 083.D-0224(C) and 088.C-0575(A).

  5. Simulation of Canopy Leaf Inclination Angle in Rice

    Directory of Open Access Journals (Sweden)

    Xiao-cui ZHANG

    2013-11-01

    Full Text Available A leaf inclination angle distribution model, which is applicable to simulate leaf inclination angle distribution in six heights of layered canopy at different growth stages, was established by component factors affecting plant type in rice. The accuracy of the simulation results was validated by measured values from a field experiment. The coefficient of determination (R2 and the root mean square error (RMSE between the simulated and measured values were 0.9472 and 3.93%, respectively. The simulation results showed that the distribution of leaf inclination angles differed among the three plant types. The leaf inclination angles were larger in the compact variety Liangyoupeijiu with erect leaves than in the loose variety Shanyou 63 with droopy leaves and the intermediate variety Liangyou Y06. The leaf inclination angles were distributed in the lower range in Shanyou 63, which matched up with field measurements. The distribution of leaf inclination angles in the same variety changed throughout the seven growth stages. The leaf inclination angles enlarged gradually from transplanting to booting. During the post-booting period, the leaf inclination angle increased in Shanyou 63 and Liangyou Y06, but changed little in Liangyoupeijiu. At every growth stage of each variety, canopy leaf inclination angle distribution on the six heights of canopy layers was variable. As canopy height increased, the layered leaf area index (LAI decreased in all the three plant types. However, while the leaf inclination angles showed little change in Liangyoupeijiu, they became larger in Shanyou 63 but smaller in Liangyou Y06. The simulation results used in the constructed model were very similar to the actual measurement values. The model provides a method for estimating canopy leaf inclination angle distribution in rice production.

  6. Soil-structure interaction on inclined soil layers

    International Nuclear Information System (INIS)

    Massa, G.; De Stefano, R.

    1983-01-01

    The case history presented deals with a Category I building having two-thirds of its base founded on a wedge of hard material. This wedge is underlain by an inclined layer of softer material, which also directly supports the remaining one-third of the foundation. The inclined layer is underlain by a third material, possessing large stiffness and extending to great depth. This case is analyzed with the methodology described below: - Determination of the static soil compliances by discretizing the foundation area into a number of strips and taking the soil profile as horizontally layered under each strip. Lumped parameter soil compliances for the whole foundation are obtained by weighting the contributions to stiffness in proportion to the area of each strip. - Definition of the degree of coupling between modes. The soil compliances defined in the previous step include coupling between the vertical and rocking modes and the horizontal and torsional modes through the positioning of the corresponding soil springs. The degree of coupling is checked through a static finite element analysis. - Frequency correction of the static soil compliances taking into account the inhomogeneity of the foundation conditions. The correction is based on obtaining dynamic stiffness coefficients for extreme configurations of the soil profile. - Assessment of the sliding potential of the structure under earthquake loading, considering eccentricities of the dynamic forces and non-uniform friction resistance over the foundation area, accounting for the frictional capacity of the different bearing materials. It is concluded that the simplified technique can provide accurate soil compliances, coupling and frequency corrections for soil-structure interaction on sloping layers, and an appropriate assessment of the sliding potential. (orig./HP)

  7. Shovel-shaped incisors in the Black Sea region population of Turkey

    Directory of Open Access Journals (Sweden)

    Emin Murat Canger

    2014-09-01

    Conclusion: The incidence of shovel-shaped incisors was 10.1% in our study group; SSI affected lateral incisors more than central incisors; the number of women reflecting SSI was higher than men; and the majority of individuals had Type II (semi-shovel severity.

  8. Effect of Incisor Angulation on Overjet and Overbite in Class II Camouflage Treatment. A typodont study.

    Science.gov (United States)

    Sangcharearn, Yasinee; Ho, Christopher

    2007-11-01

    To determine the amount of variation in overjet and overbite that may result from changes in upper and lower incisor angulations following upper first premolar extraction treatment in Class II malocclusions. Typodonts were set up to simulate a skeletal Class II occlusion treated with upper first premolar extractions. The upper incisor angulation was altered through a range from 100 degrees to 120 degrees to the palatal plane by 2 degrees increments. The overjet and overbite were measured with every 2 degrees of upper incisor angulation change. A regression analysis was performed on the experimental data, and the regression coefficients, slope, and intercept were estimated. Excessive proclination of the lower incisors will result in an abnormal overjet and overbite relationship for any magnitude of upper incisor angulation. A normal lower incisor angulation facilitates the attainment of an optimal occlusion. Excessive palatal root torque of the upper incisors will result in an increase in overjet and a consequent decrease in overbite. If the upper incisors are excessively retroclined, an edge-to-edge incisor relationship will result. Class II camouflage treatment with upper first premolar extractions requires correctly angulated incisors to achieve optimal buccal segment interdigitation and incisor relationship. Labial root torque and interproximal reduction of the lower anterior teeth should be considered when the lower incisors are excessively proclined.

  9. Self-filtering extremely inclined x-ray crystal monochromator

    Czech Academy of Sciences Publication Activity Database

    Hrdá, Jaromíra; Hrdý, Jaromír

    2011-01-01

    Roč. 44, č. 6 (2011), 1169-1172 ISSN 0021-8898 R&D Projects: GA MPO FR-TI1/412 Institutional research plan: CEZ:AV0Z10100522 Keywords : synchrotron radiation monochromator * x-ray crystal monochromator * inclined monochromator * inclined diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 5.152, year: 2011

  10. Shallow bias in Mediterranean paleomagnetic directions caused by inclination error

    NARCIS (Netherlands)

    Krijgsman, W.; Tauxe, Lisa

    2004-01-01

    A variety of paleomagnetic data from the Mediterranean region show a strong bias toward shallow inclinations. This pattern of shallow inclinations has been interpreted to be the result of (1) major northward terrane displacement, (2) large nondipole components in the Earth’s magnetic field, and

  11. Analysis of deformation due to inclined load in generalized ...

    African Journals Online (AJOL)

    The present investigation deals with study of deformation in homogeneous, isotropic thermodiffusion elastic half-space as a result of inclined load. The inclined load is assumed to be a linear combination of normal load and tangential load. The integral transform technique is used to solve the problem. As an application of ...

  12. 46 CFR 58.01-40 - Machinery, angles of inclination.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Machinery, angles of inclination. 58.01-40 Section 58.01-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-40 Machinery, angles of inclination. (a) Propulsion machinery and all auxiliary...

  13. Rationalization of incisor shape: experimental-numerical analysis.

    Science.gov (United States)

    Magne, P; Versluis, A; Douglas, W H

    1999-03-01

    Moving from the posterior segment in the anterior direction within the dental arch, the process of "incisivization" takes place. The occlusal table is gradually replaced by an incisal edge that has the function of cutting. This study considers these genetically controlled changes by using strain gauge measurements and finite element analyses to rationalize the clinical and biologic advantages of incisal form. A direct clinical link in the common esthetic procedure of anterior veneering is expected. Six maxillary incisors were mounted in a positioning device and equipped with 2 strain gauges bonded to the palatal surface: gauge 1 (G1) in the concavity and gauge 2 (G2) on the cingulum. A 50 N load was applied on the palatal side of the incisal edge, perpendicular to the long axis of the tooth. Displacement of the load tip and the palatal strain were recorded after successively removing one third, two thirds, and the total thickness of the facial enamel. The same experiment was reproduced with the finite element method (FEM). Four additional experimental designs were tested with the FEM by simulating the progressive thinning and elimination of palatal enamel and a thickened palatal lobe. Surface tangential stresses and local strain in the area corresponding to gauges 1 and 2 were calculated from the postprocessing files. The FEM was validated by experimental results considering both displacement of the load tip ( approximately 120 +/- 30 microm) and tangential surface strain at G1/G2. Recorded strains were always higher in the concavity when compared with the cingulum; high tensile strains were recorded at G1 after the total removal of the facial enamel. The entire facial surface was submitted to compressive forces. Subsequent compressive stresses were higher ( approximately 150 MPa) when facial enamel was thin or when the palatal enamel was removed. However, their absolute value never reached the elevated and potentially harmful tensile stresses measured in the

  14. Elastic Band Causing Exfoliation of the Upper Permanent Central Incisors

    Directory of Open Access Journals (Sweden)

    Monica Ghislaine Oliveira Alves

    2015-01-01

    Full Text Available Objective. This study reports a case in which elastic band use culminated in the loss of the incisors. Case Report. An 11-year-old white girl was seen complaining of pain, with purulent discharge and severe tooth mobility. The bone destruction detected radiographically in the region, despite its single location and absence in posterior quadrants of the maxilla and/or mandible, was similar to that observed in Langerhans cell disease. To our surprise, an elastic band involving the midportion of the roots of the two upper central incisors was found during biopsy. The debris was removed and a metal wire was placed in permanent maxillary right and left incisors. The patient was followed up, but no improvement in tooth mobility was observed. Bone loss increased, and internal resorption and root exposure occurred, which culminated in the extraction of permanent maxillary right and left incisors. Conclusion. The present case highlights the fact that professionals sometimes are confronted by anamnestic reports never seen before.

  15. Maxillary arch and combined incisor dimensions of Urhobos in ...

    African Journals Online (AJOL)

    The combined mesiodistal crown widths of the four maxillary permanent incisors, interpremolar and intermolar arch widths of the maxillary arch of one hundred study models (50 males and 50 females) were measured with digital Vernier Caliper. There were statistically significant gender differences in the combined ...

  16. Treatment of unerupted maxillary incisors — a case report | Umweni ...

    African Journals Online (AJOL)

    A case of unerupted maxillary left central incisor due to impedance from an odontome is presented. The problems associated with various modalities of management are highlighted in the light of current practical possibilities to achieve good aesthetics. Surgical removal of the impeding pathologic agent and orthodontic ...

  17. Factors associated with molar incisor hypomineralization in Thai children.

    Science.gov (United States)

    Pitiphat, Waranuch; Luangchaichaweng, Sarunporn; Pungchanchaikul, Patimaporn; Angwaravong, Onauma; Chansamak, Nusara

    2014-08-01

    Molar incisor hypomineralization (MIH) is a qualitative developmental enamel defect that affects one to four permanent first molars, with or without involvement of permanent incisors. Its etiology is of systemic origin, but is not well understood. Therefore, we conducted this cross-sectional study to examine pre-, peri-, and postnatal risk factors for MIH among children, 7-8 yr of age, in urban areas of Khon Kaen, Thailand. Molar incisor hypomineralization defects were diagnosed using the European Academy of Pediatric Dentistry criteria. Mothers or primary caregivers were interviewed on maternal medical history and habits during pregnancy, pregnancy and delivery complications, and the child's medical history. Molar incisor hypomineralization defects were observed in 78 (27.7%) of 282 children. Multiple logistic regression analysis showed a statistically significant association between the development of MIH and Cesarean section (adjusted OR = 2.0, 95% CI = 1.1-3.7), complications during vaginal delivery (adjusted OR = 4.5, 95% CI = 1.9-11.0), and severe/chronic illness when under 3 yr of age (adjusted OR = 2.9, 95% CI = 1.6-5.0). There was no association of preterm birth and low birth weight with MIH. The results suggest that Cesarean section, complications during vaginal delivery, and poor health during the first 3 yr of life are independent risk factors for MIH. © 2014 Eur J Oral Sci.

  18. Prevalence Of Molar Incisor Hypomineralisation In Six To Eight Year ...

    African Journals Online (AJOL)

    Objective: To determine the prevalence of molar incisor hypomineralization (MIH) and any associated causes of MIH in children from two rural divisions in Kenya. Design: Prospective cross-sectional study. Setting: Seventeen primary schools in Matungulu and Kangundo divisions of Machakos district in Kenya. Subjects: All ...

  19. Orthodontic management of an impacted maxillary central incisor ...

    African Journals Online (AJOL)

    The orthodontic management of an impacted maxillary central incisor with a talon cusp and dilacerated root in a 23-year-old female is reported. The patient presented complaining of an inability to smile because of the irregular arrangement of her front teeth. An oral examination revealed absence of the maxillary right ...

  20. Immediate maxillary lateral incisor implants with nonocclusal loading provisional crowns.

    Science.gov (United States)

    Peñarrocha, Miguel; Lamas, Joana; Peñarrocha, Maria; Garcia, Berta

    2008-01-01

    This clinical report series describes a treatment modality involving immediately placed dental implants in maxillary lateral incisor sites using noncemented immediate provisional crowns retained with calcinable copings (prosthetic complement used in preparing the metal for the definitive prosthesis). Ten implants were placed in eight patients for the replacement of maxillary lateral incisors: two immediate and eight corresponding to cases of agenesis. All were subjected to immediate rehabilitation with provisional acrylic resin crowns in nonocclusal loading. One implant failed 3 weeks after placement due to acute local trauma. The other nine remained functional within the mouth, with normal clinical and radiological characteristics after a minimum of 12-month follow-up. Immediate placement of implant fixed provisional restorations retained by friction in maxillary lateral incisors offers an esthetic solution, eliminates the need for a removable provisional restoration, and avoids implant failures associated with excess cement or screw loosening. Moreover, in the case of extractions, immediate placement and provisionalization of implants in maxillary lateral incisors can effectively optimize the peri-implant esthetic results by maintaining the existing hard and soft tissue architecture of the replaced tooth. As no cement or screws are required, and the provisional crowns are placed in nonocclusal loading, the risk of complications is minimized.

  1. Eruption of primary Incisors: prevalence of sequence reversal and ...

    African Journals Online (AJOL)

    Result: Nine (3.1 %) out of the 290 children assessed erupted the maxillary Incisors ahead of the mandibular counterparts and their mothers allowed the teeth to erupt normally. One hundred and fifty-seven (54.1 %) of the mothers agreed that the tooth should be allowed to grow normally as part of the series of the primary ...

  2. A Review Of 39 Cases Of Unerupted Maxillary Incisors | Sanu ...

    African Journals Online (AJOL)

    The presence of isolated odontomes was the most common cause of lack of eruption of the maxillary incisors with a prevalence of 20.5%. Other factors causing delayed eruption were odontomes with retained primary tooth (15.4%), presence of supernumerary teeth of especially the mesiodens type (15.4%), retained primary ...

  3. Class II malocclusion with accentuated occlusal plane inclination corrected with miniplate: a case report

    Science.gov (United States)

    Farret, Marcel Marchiori; Farret, Milton M. Benitez

    2016-01-01

    ABSTRACT Introduction: A canted occlusal plane presents an unesthetic element of the smile. The correction of this asymmetry has been typically considered difficult by orthodontists, as it requires complex mechanics and may sometimes even require orthognathic surgery. Objective: This paper outlines the case of a 29-year-old woman with Class II malocclusion, pronounced midline deviation and accentuated occlusal plane inclination caused by mandibular deciduous molar ankylosis. Methods: The patient was treated with a miniplate used to provide anchorage in order to intrude maxillary teeth and extrude mandibular teeth on one side, thus eliminating asymmetry. Class II was corrected on the left side by means of distalization, anchored in the miniplate as well. On the right side, maxillary first premolar was extracted and molar relationship was kept in Class II, while canines were moved to Class I relationship. The patient received implant-prosthetic rehabilitation for maxillary left lateral incisor and mandibular left second premolar. Results: At the end of treatment, Class II was corrected, midlines were matched and the canted occlusal plane was totally corrected, thereby improving smile function and esthetics. PMID:27409658

  4. Effect of the inclination of support in cervical and upper limb development

    Directory of Open Access Journals (Sweden)

    Ailime Perito Feiber Heck

    Full Text Available Introduction It is expected that a child will acquire control of posture (CP of the head and upper limbs in a gradual, sequential and organized way. However, there is still no consensus regarding the best position to achieve this; the evidence suggests that it is prone. Objective To investigate whether age and inclination of the supporting surface in the prone position influence the alignment of the head and upper limbs of children with typical motor development (TMD and atypical motor development (AMD. Methods The study included 29 children aged between one and three months divided according to the Alberta Infant Motor Scale (AIMS into groups with TMD (n = 18 and AMD (n = 11. The children were placed in the prone position with three angles of the support surface (0°, 25° and 45°. Kinematic analysis was conducted to evaluate the alignment angles of the head and upper limbs. Results Children with TMD had higher head alignment. There was no difference in the upper limbs’ alignment between the group with TMD and the group with AMD. In the third month of age compared with the first, increased head alignment and decreased upper limb alignment were found in both groups. The inclination of the supporting surface did not influence the alignment of the head and upper limbs. Conclusions Among the positions evaluated, the prone position without inclination of the supporting surface was more appropriate for weight discharge in the upper limbs, favoring the development of postural control of the child.

  5. Patterns of incisor-premolar agenesis combinations: A retrospective study.

    Science.gov (United States)

    Demiriz, Levent; Bodrumlu, Ebru Hazar; Kokturk, Furuzan

    2017-01-01

    Tooth agenesis is the most common dental anomaly which causes serious problems in humans. Many theories were asserted to explain the main etiologic factor of this anomaly, and genetic factors were considered as primary reasons. The aim of the present study was to evaluate the relationship between incisor and premolar tooth agenesis and to reveal a considerable data about combinations of incisor-premolar agenesis and their frequency. According to inclusion and exclusion criterion, archived panoramic radiographs of nonsyndromic 6535 patients (4077 females and 2058 males) ranging in age from 7 to 18 years old were retrospectively examined to find the presence of tooth agenesis. Panoramic radiographs showing at least one tooth agenesis were recorded, and the missing tooth or teeth excluding third molars were noted. Combinations of incisor-premolar tooth agenesis were listed, and the most affected teeth groups were noted. Collected data were statistically analyzed using Chi-square test or Fisher exact's Chi-square test. Three hundred and eight patients (4.7%) who had at least one tooth agenesis and 648 missing permanent tooth, excluding third molars, were detected. Although the sample size of females was bigger than males in all examined patients, tooth agenesis was detected significantly more in males than females (P = 0.021). Thirty-two patients (10.4%) had both incisor and premolar agenesis, and of all patients, twenty patients (6, 5%) were found to have both maxillary lateral incisor and mandibular second premolar agenesis. Combinations of tooth agenesis are an issue which has begun to take attention recently. The results of the present study may provide empirical data for further genetic studies.

  6. Patterns of incisor-premolar agenesis combinations: A retrospective study

    Directory of Open Access Journals (Sweden)

    Levent Demiriz

    2017-01-01

    Full Text Available Background: Tooth agenesis is the most common dental anomaly which causes serious problems in humans. Many theories were asserted to explain the main etiologic factor of this anomaly, and genetic factors were considered as primary reasons. Aims: The aim of the present study was to evaluate the relationship between incisor and premolar tooth agenesis and to reveal a considerable data about combinations of incisor-premolar agenesis and their frequency. Settings and Design: According to inclusion and exclusion criterion, archived panoramic radiographs of nonsyndromic 6535 patients (4077 females and 2058 males ranging in age from 7 to 18 years old were retrospectively examined to find the presence of tooth agenesis. Panoramic radiographs showing at least one tooth agenesis were recorded, and the missing tooth or teeth excluding third molars were noted. Methods: Combinations of incisor-premolar tooth agenesis were listed, and the most affected teeth groups were noted. Statistical Analysis Used: Collected data were statistically analyzed using Chi-square test or Fisher exact's Chi-square test. Results: Three hundred and eight patients (4.7% who had at least one tooth agenesis and 648 missing permanent tooth, excluding third molars, were detected. Although the sample size of females was bigger than males in all examined patients, tooth agenesis was detected significantly more in males than females (P = 0.021. Thirty-two patients (10.4% had both incisor and premolar agenesis, and of all patients, twenty patients (6, 5% were found to have both maxillary lateral incisor and mandibular second premolar agenesis. Conclusions: Combinations of tooth agenesis are an issue which has begun to take attention recently. The results of the present study may provide empirical data for further genetic studies.

  7. Managing molar-incisor hypomineralization: A systematic review.

    Science.gov (United States)

    Elhennawy, Karim; Schwendicke, Falk

    2016-12-01

    We systematically reviewed treatment modalities for MIH-affected molars and incisors. Trials on humans with ≥1 MIH molar/incisor reporting on various treatments were included. Two authors independently searched and extracted records. Sample-size-weighted annual failure rates were estimated where appropriate. The risk of bias was assessed using the Newcastle-Ottawa scale. Electronic databases (PubMed, Embase, Cochrane CENTRAL, Google Scholar) were screened, and hand searches and cross-referencing performed. Fourteen (mainly observational) studies were included. Ten trials (381 participants) investigated MIH-molars, four (139) MIH-incisors. For molars, remineralization, restorative or extraction therapies had been assessed. For restorative approaches, mean (SD) annual failure rates were highest for fissure sealants (12[6]%) and glass-ionomer restorations (12[2]%), and lowest for indirect restorations (1[3]%), preformed metal crowns (1.3 [2.1]%) and composite restorations (4[3]%). Ony study assessed extraction of molars in young patients (median age 8.2 years), the majority of them without malocclusions, but third molars in development. Spontaneous alignment of second molars was more frequent in the maxilla (55%) than the mandible (47%). For incisors, desensitizing agents successfully managed hypersensitivity. Micro-abrasion and composite veneers improved aesthetics. Few, mainly moderate to high-risk-studies investigated treatment of MIH. Remineralization or sealants seem suitable for MIH-molars with limited severity and/or hypersensitivity. For severe cases, restorations with composites or indirect restorations or preformed metal crowns seem suitable. Prior to tooth extraction as last resort factors like the presence of a general malocclusion, patients' age and the status of neighboring teeth should be considered. No recommendations can be given for MIH-incisors. Dentists need to consider the specific condition of each tooth and the needs and expectations of

  8. Avaliação da angulação e inclinação dos elementos dentários em pacientes adultos jovens portadores de fissura transforame incisivo bilateral Evaluation of tipping and inclination of teeth in young adults with complete bilateral cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Andréia Caixeta Reis

    2008-02-01

    permanent dentition, aged 12 to 27 years. The casts were prepared and the measurements were performed based on the method suggested by Andrews¹. The results achieved were the following: 1. Tipping - in the maxillary arch, positive values (positive tipping with a progressively increasing tendency were observed from the molars to the canines, and negative values for the incisors (counter-tipping. As regards the mandibular arch, decreasing positive values were found from the molars to the premolars and negative values were observed for the entire anterior region; 2. Inclination - negative values, corresponding to palatal or lingual inclination, were found for all teeth in the sample. It was concluded that the maxillary canines and incisors were the teeth most affected by the presence of the cleft; the mandibular arch kept more uniform values due to the middle influence from the cleft; the negative inclinations observed for the entire mandibular arch and the frequent anterior crowding suggest adaptation of the mandibular arch to compensate the maxillary atresia.

  9. Lateral incisor agenesis predicts maxillary hypoplasia and Le Fort I advancement surgery in cleft patients.

    Science.gov (United States)

    Lai, Li Han; Hui, Brian K; Nguyen, Phuong D; Yee, Kristen S; Martz, Martin G; Bradley, James P; Lee, Justine C

    2015-01-01

    Severe maxillary hypoplasia in cleft patients is caused by a combination of pathogenic and iatrogenic factors. In this work, the authors investigated anatomical deficiencies in dentition for predicting Le Fort I maxillary advancement surgery for severe maxillary hypoplasia in cleft patients. Cleft lip-cleft palate and cleft palate patients older than 14 years of age were reviewed for demographics, dental anomalies, and Le Fort I advancement. Chi-square tests, t tests, and multivariate logistic regression analyses were performed to delineate the contribution of quantity and position of dental agenesis to maxillary advancement surgery. In the 114 patients reviewed (mean age, 19.2 years), 64.0 percent were male patients, 71.9 percent had dental agenesis, and 59.6 percent required Le Fort I advancement. In patients who did not exhibit dental agenesis, 18.8 percent required Le Fort I advancement compared with 74.4 percent of patients with dental agenesis (p agenesis was at the lateral incisor position (p agenesis is an independent predictor for Le Fort I advancement surgery (OR, 4.4; 95 percent CI, 1.42 to 13.64; p = 0.01). Lateral incisor agenesis correlated to maxillary hypoplasia and independently predicted the need for Le Fort I advancement in cleft patients, potentially as an anatomical readout of intrinsic growth deficiency. Risk, III.

  10. Parental satisfaction with bonded resin composite strip crowns for primary incisors.

    Science.gov (United States)

    Kupietzky, Ari; Waggoner, William F

    2004-01-01

    The purpose of this study was to evaluate the parental satisfaction of bonded resin composite strip crowns for the treatment of maxillary anterior primary incisors and compare their satisfaction with the clinical evaluation and success of the crowns. This was a retrospective, clinical study of patients who had strip crowns (SC) placed on maxillary primary incisors, returned for at least 1 recall examination, and whose parents gave consent for them to participate in the study. Color photographs were used for evaluation by 2 independent pediatric dentists. Parental satisfaction regarding the esthetics of the crowns was evaluated by a questionnaire. One hundred and twelve restorations placed in 40 children were evaluated. The evaluations were performed after the crowns had been in place for an average of 18 months (range=6-25 months). Overall parental satisfaction with the treatment was excellent; however, satisfaction with regard to color received the lowest rating. No significant differences were found between dentist and parent evaluations of color, size, and overall appearance (Fisher exact test; P=.194,.776,.291, respectively). Parents rated their overall satisfaction as being positive regardless of their poor ratings of color, size, or overall appearance. However, a significant relationship was found between durability and overall satisfaction (P=.046). Parents who gave poor ratings to durability also rated their overall satisfaction as being poor. Parental satisfaction with bonded resin composite SCs for the treatment of primary incisors with large or multi-surface caries was excellent. Parents' dissatisfaction was most often related to color of the restorations. However, this did not affect their overall satisfaction with the crowns. The durability of restorations negatively affected the rating of overall satisfaction with the crown. Durability seems to be of more concern than excellent color match to this group of parents.

  11. Prevalence of molar incisor hypomineralization in the city of Buenos Aires.

    Science.gov (United States)

    Biondi, Ana M; Cortese, Silvina G; Martínez, Karina; Ortolani, Andrea M; Sebelli, Patricia M F; Ienco, Melisa; Paván, Verónica H; Mendel, Nancy; Bertolino, Mariana; Hecht, Pedro

    2011-01-01

    The prevalence of Molar Incisor Hypomineralization (MIH) still remains unknown in Argentina. The objectives of this work were to: estimate prevalence of MIH in a group of children seeking dental care in the city of Buenos Aires, analyze distribution according to year of birth and compare prevalence and severity of MIH in children with different access to health care services. A prospective, observational, transversal, descriptive study was designed, to be conducted on children seeking attention at Department of Comprehensive Children's Dentistry at the School of Dentistry of Buenos Aires University and at 3 pediatric dentistry offices attended by members of the team, located in Buenos Aires city (Kappa 0.933 0.911-0.952), from April to August 2010. The study included all children born between 1993 and 2003, whose 4 first molars and 8 permanent incisors had erupted. After prophylaxis and drying, the teeth were clinically evaluated and specially designed charts were used to record sex, year of birth, type of access to dental care, presence of MIH, number of affected incisors and molars, and maximum degree of severity for each tooth. The data obtained were analyzed using percentages, Fisher's Exact Test and Linear regression. 1098 children, mean age 11.3 years (11.08-11.39) were evaluated. Prevalence of MIH in this study was 15.9% (13.8-18.2). A highly significant positive correlation was obtained between MIH and year of birth (pprevalence was 24.40% (20.9-27.9) while in Group B it was 6.44% (4.31-8.56) (pprevalence and degree of severity of MIH.

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

    Science.gov (United States)

    2016-01-01

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

  13. ANISOTROPY-BASED INCLINATION CORRECTION FOR THE MOENAVE FORMATION AND WINGATE SANDSTONE: IMPLICATIONS FOR COLORADO PLATEAU ROTATION

    Directory of Open Access Journals (Sweden)

    Andrea eMcCall

    2014-07-01

    Full Text Available The ~ 201 Ma paleopole for North America at the Triassic-Jurassic boundary is observed in two widely different locations; one paleopole is determined from the Mesozoic rift basins in eastern North America and the other from the Colorado Plateau in the southwestern United States. A large discrepancy in paleopole positions from these two localities has been attributed to large amounts of clockwise vertical axis rotation of the Colorado Plateau (>10º combined with inclination shallowing of the paleomagnetism. The sedimentary inclinations of the eastern North American basins have been corrected for shallowing, but the Colorado Plateau inclinations have not. Simple vertical axis rotation of the Colorado Plateau is not enough to bring the two paleopoles into agreement. This study of the Moenave and Wingate Formations was conducted to correct Colorado Plateau inclinations using their high field isothermal remanent anisotropy. The Moenave Formation and laterally equivalent Wingate Sandstone, which span the Triassic-Jurassic boundary, were sampled in southern Utah and northern Arizona. Thermal demagnetization isolated a characteristic remanence carried by hematite from 20 sites. High field (5 T isothermal remanent anisotropy indicated shallowing of the characteristic remanence with an average flattening factor of f=0.69. An inclination-corrected paleopole for the Moenave and Wingate Formations is located at 62.5˚N 69.9˚E (α95=5.5˚ and is shifted northward by 2.9˚ with respect to the uncorrected paleopole. When the inclination corrected paleopole is rotated counterclockwise 9.7º about an Euler pole local to the Colorado Plateau, it is statistically indistinguishable from the inclination-corrected paleopole from the eastern North American rift basins. Rotation of the uncorrected paleopole does not bring it into statistical agreement with rift basin paleopole, therefore an inclination shallowing correction is necessary to support rotation of the

  14. Fluorescence intensity dependence on the propagation plane inclination

    International Nuclear Information System (INIS)

    Fernandez, J.E.; Rubio, Marcelo; Sanchez, H. J.

    1987-01-01

    An experimental confirmation of the fluorescence intensity behaviour with the inclination of the propagation plane (α angle) was carried out. A special angular sample-holder was developed and set up on our X-ray spectrometer. This sample-holder allows different positions of irradiation of the sample modifying the α angle until the maximum angle (α Μ ) is reached in the limit situation. In this work, this maximum angle was 86 deg and the incidence and take off angles were both 45 deg. The sample-holder and the collimation system were carefully lined up. The fluorescent spectra of three National Bureau of Standards (NBS) standard samples were taken for sixteen different α angle positions. The theoretical scheme for both enhanced fluorescent lines and nonenhanced fluorescent lines was confirmed, i.e. the invariance of the primary intensity with the α angle and the decline of the enhanced fluorescence intensities under the same conditions. This experimental confirmation agrees with theoretical prediction: the vanishing of the secondary fluorescence in the extreme case α = π/2. (Author) [es

  15. Atypical presentation of bilateral supplemental maxillary central incisors with unusual talon cusp

    Directory of Open Access Journals (Sweden)

    Sivakumar Nuvvula

    2011-01-01

    Full Text Available Delayed eruption of maxillary permanent central incisors in a child poses a distressing esthetic quandary to parents, by virtue of its location in the dental architecture. Well-aligned anterior teeth add confidence to smile and have enhanced self-esteem, which is critical even in early life. Impaction of the maxillary central incisors compared to third molars or the canines is less reported; bilateral supplemental maxillary central incisors related to impacted permanent maxillary central incisors are rare and one of the supplemental central incisors showing unusual talon is still infrequent. A case of impacted maxillary permanent central incisors related to supplemental maxillary central incisors, with one of them showing an unusual talon cusp, is presented.

  16. Treating Class II patients with removable plates and functional orthopedic appliances-the importance of anterior tooth inclination and direction of growth on treatment outcome.

    Science.gov (United States)

    Hönn, Mirjam; Schneider, Colette; Dietz, Klaus; Godt, Arnim; Göz, Gernot

    2006-07-01

    To determine the influence of physiological growth pattern and anterior tooth inclination on the outcome in Class II patients treated with removable orthodontic plates and functional orthodontic appliances. After recruiting 50 patients with an upper anterior proclination of 1-SN >or= 107 degrees for this retrospective study, another 50 patients with a retroclination of 1-SN appliances was initiated in mixed dentition. Pre- and post-treatment lateral cephalograms were evaluated for each patient. Dento-alveolar analysis showed that the inclination of the upper incisors changed in the direction of the clinical standard value independent of the craniofacial configuration, although full correction using removable orthodontic plates and functional orthodontic appliances was not always achieved. Similarly good treatment outcomes were achieved with regard to overjet and overbite. The lower incisors of all patients were in proclination after treatment. The ANB angle was reduced in both groups. Nevertheless, on average a skeletal Class II persisted in the Class II, Division 2 patients, while Class II, Division 1 patients with horizontal craniofacial configurations attained skeletal Class I. Treatment of Class II patients with removable appliances resulted in differences depending on anterior tooth inclination (Class II, Division 1 and II, Division 2) and craniofacial configuration. These differences must be taken into account during treatment planning. Complete treatment success with regard to sagittal jaw balance is very difficult to achieve with removable orthodontic plates (pre-treatment) and functional orthodontic appliances alone in Class II, Division 1 cases with a vertical craniofacial configuration and generally in Class II, Division 2 cases. A particularly favorable constellation for removable treatment is a Class II, Division 1 situation with a horizontal craniofacial configuration and retroclined or orthognathic mandibular anteriors.

  17. Inclined asymmetric librations in exterior resonances

    Science.gov (United States)

    Voyatzis, G.; Tsiganis, K.; Antoniadou, K. I.

    2018-04-01

    Librational motion in Celestial Mechanics is generally associated with the existence of stable resonant configurations and signified by the existence of stable periodic solutions and oscillation of critical (resonant) angles. When such an oscillation takes place around a value different than 0 or π , the libration is called asymmetric. In the context of the planar circular restricted three-body problem, asymmetric librations have been identified for the exterior mean motion resonances (MMRs) 1:2, 1:3, etc., as well as for co-orbital motion (1:1). In exterior MMRs the massless body is the outer one. In this paper, we study asymmetric librations in the three-dimensional space. We employ the computational approach of Markellos (Mon Not R Astron Soc 184:273-281, https://doi.org/10.1093/mnras/184.2.273, 1978) and compute families of asymmetric periodic orbits and their stability. Stable asymmetric periodic orbits are surrounded in phase space by domains of initial conditions which correspond to stable evolution and librating resonant angles. Our computations were focused on the spatial circular restricted three-body model of the Sun-Neptune-TNO system (TNO = trans-Neptunian object). We compare our results with numerical integrations of observed TNOs, which reveal that some of them perform 1:2 resonant, inclined asymmetric librations. For the stable 1:2 TNO librators, we find that their libration seems to be related to the vertically stable planar asymmetric orbits of our model, rather than the three-dimensional ones found in the present study.

  18. Development of locomotion over inclined surfaces in laying hens.

    Science.gov (United States)

    LeBlanc, C; Tobalske, B; Bowley, S; Harlander-Matauschek, A

    2018-03-01

    The purpose of the present study was to evaluate locomotor strategies during development in domestic chickens (Gallus gallus domesticus); we were motivated, in part, by current efforts to improve the design of housing systems for laying hens which aim to reduce injury and over-exertion. Using four strains of laying hens (Lohmann Brown, Lohmann LSL lite, Dekalb White and Hyline Brown) throughout this longitudinal study, we investigated their locomotor style and climbing capacity in relation to the degree (0 to 70°) of incline, age (2 to 36 weeks) and the surface substrate (sandpaper or wire grid). Chicks and adult fowl performed only walking behavior to climb inclines ⩽40° and performed a combination of wing-assisted incline running (WAIR) or aerial ascent on steeper inclines. Fewer birds used their wings to aid their hind limbs when climbing 50° inclines on wire grid surface compared with sandpaper. The steepness of angle achieved during WAIR and the tendency to fly instead of using WAIR increased with increasing age and experience. White-feathered strains performed more wing-associated locomotor behavior compared with brown-feathered strains. A subset of birds was never able to climb incline angles >40° even when using WAIR. Therefore, we suggest that inclines of up to 40° should be provided for hens in three-dimensional housing systems, which are easily negotiated (without wing use) by chicks and adult fowl.

  19. Natural Circulation Characteristics of a Symmetric Loop under Inclined Conditions

    Directory of Open Access Journals (Sweden)

    Xingtuan Yang

    2014-01-01

    Full Text Available Natural circulation is an important process for primary loops of some marine integrated reactors. The reactor works under inclined conditions when severe accidents happen to the ship. In this paper, to investigate the characteristics of natural circulation, experiments were conducted in a symmetric loop under the inclined angle of 0~45°. A CFD model was also set up to predict the behaviors of the loop beyond the experimental scope. Total circulation flow rate decreases with the increase of inclined angle. Meanwhile one circulation is depressed while the other is enhanced, and accordingly the disparity between the branch circulations arises and increases with the increase of inclined angle. Circulation only takes place in one branch circuit at large inclined angle. Also based on the CFD model, the influences of flow resistance distribution and loop configuration on natural circulation are predicted. The numerical results show that to design the loop with the configuration of big altitude difference and small width, it is favorable to reduce the influence of inclination; however too small loop width will cause severe reduction of circulation ability at large angle inclination.

  20. [Investigation of molar-incisor hypomineralization among children from 6 to 11 years in Lucheng district, Wenzhou city].

    Science.gov (United States)

    Li, Ling; Li, Jun

    2012-10-01

    To investigate and analyze the prevalence and severity of molar-incisor hypomineralization(MIH) among children from 6 to 11 years old in Lucheng district of Wenzhou city. Children aged 6 to 11 years (n=988) with all four-first permanent molars erupted were evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria. Examiners recorded the severity and position of each tooth diagnosed with MIH. SPSS 13.0 software package was used for analyze. Kruskal-Wallis test was used to determine the differences in the defect severity among different ages and the difference in the prevalence of MIH between the upper and lower molars or between the upper and lower incisors. Spearman test was used to test the association of the MIH-defect severity with the age of children. Molar-incisor hypomineralization was present in 25.5% of the 988 children, and the majority of the defects presented were mild. There were significant differences among the six age groups with the severity of MIH (P0.05). The severity of MIH increased along with the aging of children (rp=0.534). Despite the high prevalence of MIH, the severity of the defects was mild. The results indicate a positive association between the severity of MIH and the age of children.

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

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    Ritesh R Kalaskar

    2011-01-01

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

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

    Science.gov (United States)

    Kalaskar, Ritesh R; Kalaskar, Ashita R

    2011-01-01

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

  3. Molar incisor hypomineralization: prevalence, severity and clinical consequences in Brazilian children.

    Science.gov (United States)

    da Costa-Silva, Cristiane Maria; Jeremias, Fabiano; de Souza, Juliana Feltrin; Cordeiro, Rita de Cássia Loiola; Santos-Pinto, Lourdes; Zuanon, Angela Cristina Cilense

    2010-11-01

    The prevalence of molar incisor hypomineralization (MIH) varies considerably around the world; however, few studies have examined MIH in South American countries. To evaluate the prevalence, severity, and clinical consequences of MIH in Brazilian children residing in rural and urban areas of the municipality of Botelhos, Minas Gerais, Brazil. Children aged 6 to 12 years (n = 918) with all four-first permanent molars erupted had these teeth evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria. The examinations were conducted by two previously trained examiners, and the dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Molar incisor hypomineralization was present in 19.8% of the 918 children, with a higher prevalence in rural areas. The majority of the defects presented were demarcated opacities without post-eruptive structural loss, which has been considered as mild defects. Children with MIH had higher DMFT values. Despite the high prevalence of MIH, the severity of the defects was mild. The results indicate a positive association between MIH and the presence of dental caries. © 2010 The Authors. International Journal of Paediatric Dentistry © 2010 BSPD, IAPD and Blackwell Publishing Ltd.

  4. Direct restoration modalities of fractured central maxillary incisors: A multi-levels validated finite elements analysis with in vivo strain measurements.

    Science.gov (United States)

    Davide, Apicella; Raffaella, Aversa; Marco, Tatullo; Michele, Simeone; Syed, Jamaluddin; Massimo, Marrelli; Marco, Ferrari; Antonio, Apicella

    2015-12-01

    To quantify the influence of fracture geometry and restorative materials rigidity on the stress intensity and distribution of restored fractured central maxillary incisors (CMI) with particular investigation of the adhesive interfaces. Ancillary objectives are to present an innovative technology to measure the in vivo strain state of sound maxillary incisors and to present the collected data. A validation experimental biomechanics approach has been associated to finite element analysis. FEA models consisted of CMI, periodontal ligament and the corresponding alveolar bone process. Three models were created representing different orientation of the fracture planes. Three different angulations of the fracture plane in buccal-palatal direction were modeled: the fracture plane perpendicular to the long axis in the buccal-palatal direction (0°); the fracture plane inclined bucco-palatally in apical-coronal direction (-30°); the fracture plane inclined palatal-buccally in apical-coronal direction (+30°). First set of computing runs was performed for in vivo FE-model validation purposes. In the second part, a 50N force was applied on the buccal aspect of the CMI models. Ten patients were selected and subjected to the strain measurement of CMI under controlled loading conditions. The main differences were noticed in the middle and incisal thirds of incisors crowns, due to the presence of the incisal portion restoration. The stress intensity in -30° models is increased in the enamel structure close to the restoration, due to a thinning of the remaining natural tissues. The rigidity of the restoring material slightly reduces such phenomenon. -30° model exhibits the higher interfacial stress in the adhesive layer with respect to +30° and 0° models. The lower stress intensity was noticed in the 0° models, restoration material rigidity did not influenced the interfacial stress state in 0° models. On the contrary, material rigidity influenced the interfacial stress state

  5. Individuals with a vestibular-related disorder use a somatosensory-dominant strategy for postural orientation after inclined stance.

    Science.gov (United States)

    Chong, R; Berl, B; Cook, B; Turner, P; Walker, K

    2017-06-01

    The visual, somatosensory, and vestibular systems are critical for establishing a sensorimotor set for postural control and orientation. The goal of this study was to assess how individuals with a vestibular-related disorder keep their balance following prolonged stance on an inclined surface. We hypothesize that subjects will show greater reliance on the somatosensory system than age-matched controls as inferred by the presence of a forward postural lean aftereffect following the inclined stance (i.e., a positive response). The results revealed an underlying somatosensory-dominant strategy for postural control in the vestibular group: 100% of the subjects tested positive compared to 58% in the control group (P=.006). Individuals with a vestibular-related disorder use a somatosensory-dominant strategy for postural orientation following prolonged inclined stance. The implications for the management of this population are discussed. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Management of avulsed permanent maxillary central incisors during endotracheal intubation

    Directory of Open Access Journals (Sweden)

    Ritesh R Kalaskar

    2016-01-01

    Full Text Available Avulsion is serious injury that may encounter during endotracheal intubation and its management often presents a challenge. Replantation of the avulsed tooth can restore esthetic appearance and occlusal function shortly after the injury. The present article describes the management of air-dried maxillary permanent incisors that have been avulsed due to direct laryngoscopy during the induction of general anesthesia for tonsillectomy procedure. The replanted maxillary central incisors had maintained its function and esthetic for 1 year after replantation. Children in a mixed dentition phase are high-risk group children for traumatic dental injury during laryngoscopy; therefore, Anesthetic Departments should have local protocols to refer patients for dental treatment postoperatively in the event of trauma.

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

    Directory of Open Access Journals (Sweden)

    Rahul S Baldawa

    2011-01-01

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

  8. Molar incisor hypomineralization (MIH): clinical presentation, aetiology and management.

    Science.gov (United States)

    Weerheijm, K L

    2004-01-01

    In this paper, the current knowledge about Molar Incisor Hypomineralization (MIH) is presented. MIH is defined as hypomineralization of systemic origin of one to four permanent first molars frequently associated with affected incisors and these molars are related to major clinical problems in severe cases. At the moment, only limited data are available to describe the magnitude of the phenomenon. The prevalence of MIH in the different studies ranges from 3.6-25% and seems to differ in certain regions and birth cohorts. Several aetiological factors (for example, frequent childhood diseases) are mentioned as the cause of the defect. Children at risk should be monitored very carefully during the period of eruption of their first permanent molars. Treatment planning should consider the long-term prognosis of these teeth.

  9. Aqua/Aura Spring 2017 Inclination Adjust Maneuver Series

    Science.gov (United States)

    Noyes, Thomas; Stezelberger, Shane

    2017-01-01

    This will be presented at the International Earth Science Constellation Mission Operations Working Group meeting June 13-15, 2017 to discuss the AquaAura Spring 2017 Inclination Adjust Maneuver series.

  10. Brilliance and flux reduction in imperfect inclined crystals

    International Nuclear Information System (INIS)

    Lee, W.K.; Blasdell, R.C.; Fernandez, P.B.; Macrander, A.T.; Mills, D.M.

    1996-01-01

    The inclined crystal geometry has been suggested as a method of reducing the surface absorbed power density of high-heat-load monochromators for third-generation synchrotron radiation sources. Computer simulations have shown that if the crystals are perfectly aligned and have no strains then the diffraction properties of a pair of inclined crystals are very similar to a pair of conventional flat crystals with only subtle effects differentiating the two configurations. However, if the crystals are strained, these subtle differences in the behavior of inclined crystals can result in large beam divergences causing brilliance and flux losses. This manuscript elaborates on these issues and estimates potential brilliance and flux losses from strained inclined crystals at the APS

  11. Systems of pillarless working of adjacent, sloped and inclined seams

    Energy Technology Data Exchange (ETDEWEB)

    Batmanov, Yu.K.; Bakhtin, A.F.; Bulavka, E.I.

    1979-01-01

    An analysis is made (advantages and disadvantages) of existing and recommended (pillarless) systems of working adjacent, sloped, and inclined seams. The economic benefits, area and extent of those systems are indicated. 8 references, 4 figures.

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

    OpenAIRE

    Zawawi, Khalid H.

    2014-01-01

    Mandibular incisor extraction for orthodontic treatment is considered an unusual treatment option because of the limited number of patients that meet the criteria for such treatment. Accurate diagnosis and treatment planning is essential to achieve the desired results. Adult orthodontic patients are increasingly motivated by esthetic considerations and reject the idea of conventional fixed appliances. In recent years, Invisalign appliances have gained tremendous attention for orthodontic trea...

  13. Talon cusps in mandibular incisors: Report of eight rare cases

    Directory of Open Access Journals (Sweden)

    Shiu-yin Cho

    2014-01-01

    Full Text Available Talon cusps in mandibular anterior teeth are very rare. Talon cusps in mandibular anterior teeth associated with other anomalies are even rarer and that a bilateral case in the mandible has not been reported before. In this report, eight such rare cases of talon cusps in permanent mandibular incisors are presented. It includes a bilateral case that in the author′s knowledge is the first case reported in the English literatures.

  14. Psychosocial Determinants of Romantic Inclination Among Indian Youth

    OpenAIRE

    D. Barani Ganth; S. Kadhiravan

    2017-01-01

    The present study was conducted with the aim of understanding the psychosocial determinants of romantic inclination among youth in India. We involved 779 student participants from a large central university in south India in the age range of 18-24 years. The participants filled measures on romantic inclination, personality, attachment style, interpersonal attraction, and social influence on romantic relationship in addition to a questionnaire on demographic information and relationship histor...

  15. Molar incisor hypomineralization: review and recommendations for clinical management.

    Science.gov (United States)

    William, Vanessa; Messer, Louise B; Burrow, Michael F

    2006-01-01

    Molar incisor hypomineralization (MIH) describes the clinical picture of hypomineralization of systemic origin affecting one or more first permanent molars (FPMs) that are associated frequently with affected incisors. Etiological associations with systemic conditions or environmental insults during the child's first 3 years have been implicated. The complex care involved in treating affected children must address their behavior and anxiety, aiming to provide a durable restoration under pain-free conditions. The challenges include adequate anaesthesia, suitable cavity design, and choice of restorative materials. Restorations in hypomineralized molars appear to fail frequently; there is little evidence-based literature to facilitate clinical decisions on cavity design and material choice. A 6-step approach to management is described: (1) risk identification; (2) early diagnosis; (3) remineralization and desensitization; (4) prevention of caries and posteruption breakdown; (5) restorations and extractions; and (6) maintenance. The high prevalence of MIH indicates the need for research to clarify etiological factors and improve the durability of restorations in affected teeth. The purpose of this paper was to describe the diagnosis, prevalence, putative etiological factors, and features of hypomineralized enamel in molar incisor hypomineralization and to present a sequential approach to management.

  16. Replantation of permanent incisors in children using Emdogain.

    Science.gov (United States)

    Barrett, Edward J; Kenny, David J; Tenenbaum, Howard C; Sigal, Michael J; Johnston, Douglas H

    2005-10-01

    The aim of this study was to determine whether application of an enamel matrix protein derivative, Emdogain (Biora AB Malmo, Sweden) to the root surface of avulsed permanent incisors would improve postreplantation outcomes in a pediatric population. Between June 1999 and May 2002, 25 avulsed permanent maxillary incisors (22 centrals and three laterals) were treated with Emdogain and followed for up to 32 months, mean duration 20.6 months (range: 6.9-32.5 months). Mean patient age at the time of treatment was 12.0 years (range: 7.7-17.6 years) and mean extra-alveolar duration was 185 min (range: 100-300 min). At the end of their follow-up each of the replanted incisors demonstrated radiographic evidence of replacement root resorption and clinical evidence of ankylosis. None of the replanted teeth were affected by inflammatory root resorption and there was no evidence of infection. When compared with the control samples from Barrett and Kenny (Endod Dent Traumatol 1997;15:269-72.) and Andersson et al. (Endod Dent Traumatol 1989;5:38-47.) this sample treated with the Emdogain protocol demonstrated significantly less root resorption than either of the control samples (anova, P Emdogain protocol did not produce periodontal regeneration, it did eliminate inflammatory resorption and infection and led to significantly less root resorption compared with the two historical controls.

  17. Trunk muscle activity with different sitting postures and pelvic inclination.

    Science.gov (United States)

    Watanabe, Masahiro; Kaneoka, Koji; Wada, Yusuke; Matsui, Yasushi; Miyakawa, Shumpei

    2014-01-01

    Sitting posture may often place large burden on trunk muscles, while trunk muscle activities in the sitting posture have not been well clarified. In this study, a difference in trunk muscle activity between two kinds of sitting postures was evaluated, focusing on low back pain induced by posture holding. An experiment was conducted on the subjects sitting on a stable-seat and on an unstable-seat, with the pelvis inclined forward, backward, rightward, and leftward. With the pelvis inclined forward, rightward and leftward, muscle activities were significantly increased in a stable-seat sitting posture. In contrast, no significant increase in muscle activity was observed with the pelvis inclined in every direction in an unstable-seat sitting posture. With the pelvis inclined in the stable-seat sitting posture, muscle activities were imbalanced, while with the pelvis inclined in the unstable-seat sitting posture, muscle activities were not imbalanced. Thus, it is suggested that with the pelvis inclined to the maximum extent in the stable-seat sitting posture, low back pain may be induced by imbalanced muscle activities.

  18. Inclination evolution of protoplanetary discs around eccentric binaries

    Science.gov (United States)

    Zanazzi, J. J.; Lai, Dong

    2018-01-01

    It is usually thought that viscous torque works to align a circumbinary disc with the binary's orbital plane. However, recent numerical simulations suggest that the disc may evolve to a configuration perpendicular to the binary orbit ('polar alignment) if the binary is eccentric and the initial disc-binary inclination is sufficiently large. We carry out a theoretical study on the long-term evolution of inclined discs around eccentric binaries, calculating the disc warp profile and dissipative torque acting on the disc. For discs with aspect ratio H/r larger than the viscosity parameter α, bending wave propagation effectively makes the disc precess as a quasi-rigid body, while viscosity acts on the disc warp and twist to drive secular evolution of the disc-binary inclination. We derive a simple analytic criterion (in terms of the binary eccentricity and initial disc orientation) for the disc to evolve towards polar alignment with the eccentric binary. When the disc has a non-negligible angular momentum compared to the binary, the final 'polar alignment' inclination angle is reduced from 90°. For typical protoplanetary disc parameters, the time-scale of the inclination evolution is shorter than the disc lifetime, suggesting that highly inclined discs and planets may exist orbiting eccentric binaries.

  19. Thermo-economic performance of inclined solar water distillation systems

    Directory of Open Access Journals (Sweden)

    Agboola Phillips O.

    2015-01-01

    Full Text Available This study investigates the thermo-economic performance of different configurations of inclined solar water desalination for parameters such as daily production, efficiency, system cost and distilled water production cost. The four different configurations considered for this study are as follows; 1. Inclined solar water distillation with bare absorber plate (IISWD with daily production of 5.46 kg/m2 day and daily efficiency of 48.3%. 2. Inclined solar water distillation with wick on absorber plate (IISWDW with daily production of 6.41kg/m2 day and daily efficiency 50.3%. 3. Inclined solar water distillation with wire mesh on absorber plate (IISWDWM with daily production n of 3.03 kg/m2 day and daily efficiency 32.6%. 4. Inclined solar water distillation with bare absorber plate (ISWD. (Control System with daily production of 3.25 kg/m2 day and daily efficiency of 40.1%. The systems potable water cost price ranges from 0.03 $/L for IISWDW to 0.06$/L for IISWDWM System. All the systems are economically and technically feasible as a solar distillation system for potable water in Northern Cyprus. The price of potable water from water vendors/hawkers ranges from 0.11-0.16 $/L. It is more economically viable to have the rooftop inclined solar water desalination system than procuring potable water from vendors.`

  20. TRANSIT TIMING VARIATIONS FOR INCLINED AND RETROGRADE EXOPLANETARY SYSTEMS

    International Nuclear Information System (INIS)

    Payne, Matthew J.; Ford, Eric B.; Veras, Dimitri

    2010-01-01

    We perform numerical calculations of the expected transit timing variations (TTVs) induced on a hot-Jupiter by an Earth-mass perturber. Motivated by the recent discoveries of retrograde transiting planets, we concentrate on an investigation of the effect of varying relative planetary inclinations, up to and including completely retrograde systems. We find that planets in low-order (e.g., 2:1) mean-motion resonances (MMRs) retain approximately constant TTV amplitudes for 0 deg. 170 deg. Systems in higher order MMRs (e.g., 5:1) increase in TTV amplitude as inclinations increase toward 45 deg., becoming approximately constant for 45 deg. 135 deg. Planets away from resonance slowly decrease in TTV amplitude as inclinations increase from 0 deg. to 180 deg., whereas planets adjacent to resonances can exhibit a huge range of variability in TTV amplitude as a function of both eccentricity and inclination. For highly retrograde systems (135 deg. < i ≤ 180 deg.), TTV signals will be undetectable across almost the entirety of parameter space, with the exceptions occurring when the perturber has high eccentricity or is very close to an MMR. This high inclination decrease in TTV amplitude (on and away from resonance) is important for the analysis of the known retrograde and multi-planet transiting systems, as inclination effects need to be considered if TTVs are to be used to exclude the presence of any putative planetary companions: absence of evidence is not evidence of absence.

  1. Upper Incisor Changes Due to Modifying the Point of Application of Forces during Space Closure in MBT Technique

    Directory of Open Access Journals (Sweden)

    H. Ravanmehr

    2004-06-01

    Full Text Available Statement of Problem: A recent technique (MBT has been introduced for easy and efficient orthodontic treatment by means of straight wire fixed appliances. Although this technique has many advantages, in space closure stage causes up righting problem in upper incisors, which should be adjusted by applying additional torque in anterior region.Purpose: The purpose of this clinical trial was to determine whether there is a significant difference in final incisor inclination (torque of two groups one treated with MBT technique and the other by changing the point of application of the closing force (in anterior region.Materials and Methods: Twelve patients (8 girls, 4 boys with Cl I malocclusion and crowding, whom were candidate for first premolars extraction, were selected.For space closure, 6 anterior teeth (canine to canine in upper and lower jaws ligated and the applied force was from the hooks on canines to hooks on the first molars.After space closure the results compared with the results of a previous study which treatment plan was according to original MBT technique (anterior hooks soldered to arch wire. Forces applied randomly among quadrants by NiTi coil spring (American Orthodontics Co. or active tie backs with elastic modules (Dentaurum Co.Results: The results showed a statistically significant difference between final torques of two techniques (P=0.0001. Also, the rate of space closure with NiTi coils was significantly greater than active tie back (P=0.0001.Conclusion: Anchorage loss in two groups compared and the results indicated significantly lower anchorage loss in NiTi coil spring group (P=0.035.

  2. Evaluation of performance of veterinary in-clinic hematology analyzers.

    Science.gov (United States)

    Rishniw, Mark; Pion, Paul D

    2016-12-01

    A previous study provided information regarding the quality of in-clinic veterinary biochemistry testing. However, no similar studies for in-clinic veterinary hematology testing have been conducted. The objective of this study was to assess the quality of hematology testing in veterinary in-clinic laboratories using results obtained from testing 3 levels of canine EDTA blood samples. Clinicians prepared blood samples to achieve measurand concentrations within, below, and above their RIs and evaluated the samples in triplicate using their in-clinic analyzers. Quality was assessed by comparison of calculated total error with quality requirements, determination of sigma metrics, use of a quality goal index, and agreement between in-clinic and reference laboratory instruments. Suitability for statistical quality control was determined using adaptations from the computerized program, EZRules3. Evaluation of 10 veterinary in-clinic hematology analyzers showed that these instruments often fail to meet quality requirements. At least 60% of analyzers reasonably determined RBC, WBC, HCT, and HGB, when assessed by most quality goal criteria; platelets were less reliably measured, with 80% deemed suitable for low platelet counts, but only 30% for high platelet counts, and automated differential leukocyte counts were generally considered unsuitable for clinical use with fewer than 40% of analyzers meeting the least stringent quality goal requirements. Fewer than 50% of analyzers were able to meet requirements for statistical quality control for any measurand. These findings reflect the current status of in-clinic hematology analyzer performance and provide a basis for future evaluations of the quality of veterinary laboratory testing. © 2016 American Society for Veterinary Clinical Pathology.

  3. Structural equation modeling for alteration of occlusal plane inclination.

    Science.gov (United States)

    Shigeta, Yuko; Ogawa, Takumi; Nakamura, Yoshiharu; Ando, Eriko; Hirabayashi, Rio; Ikawa, Tomoko

    2015-07-01

    Occlusal plane inclination is important to maintain a normal opening closing/biting function. However, there can be several causes that lead to alterations of the occlusal plane. The purpose of this study was to observe variations of occlusal plane inclination in adult patients, and to uncover the factors affecting changes in occlusal plane inclination with aging. Subjects were 143 patients. A cephalometric image was taken of these patients. In this study, our inquiry points were age, 3 variables on intra-oral findings, and 7 variables on cephalometric analysis. To evaluate the possible causes that affect occlusal plane inclination, factor analysis was carried out, and each component was treated as factors, which were then statistically applied to a structural equation model. Statistical analysis was carried out through the SPSS 20.0 (SPSS Inc., Chicago, USA). In all patients, Camper-occlusal plane angle (COA) ranged from -25.7 to -4.9° (Mean±SD: -6.4±5.36). In the 60 patients who had no missing teeth, COA ranged from -11.6 to -4.9° (Mean±SD: -3.3±3.31). From the results of the structural analysis, it was suggested that the occlusal plane changes to counter-clockwise (on the right lateral cephalograms) with aging. In this study, variations of occlusal plane inclination in adult patients were observed, and the factors affecting changes in occlusal plane inclination with aging were investigated via factor analysis. From our results, it was suggested that the mandibular morphology change and loss of teeth with aging influence occlusal plane inclination. Copyright © 2015 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  4. COMPUTED TOMOGRAPHIC FEATURES OF INCISOR PSEUDO-ODONTOMAS IN PRAIRIE DOGS (CYNOMYS LUDOVICIANUS).

    Science.gov (United States)

    Pelizzone, Igor; Di Ianni, Francesco; Volta, Antonella; Gnudi, Giacomo; Manfredi, Sabrina; Bertocchi, Mara; Parmigiani, Enrico

    2017-05-01

    Maxillary incisor pseudo-odontomas are common in pet prairie dogs and can cause progressive respiratory obstruction, while mandibular pseudo-odontomas are rarely clinically significant. The aim of this retrospective cross-sectional study was to describe CT features of maxillary and mandibular incisor pseudo-odontomas vs. normal incisors in a group of pet prairie dogs. All pet prairie dogs with head CT scans acquired during the period of 2013-2015 were included. A veterinary radiologist who was aware of final diagnosis reviewed CT scans and recorded qualitative features of affected and normal incisors. Mean density values for the pulp cavity and palatal and buccal dentin were also recorded. A total of 16 prairie dogs were sampled (12 normal maxillary incisors, 20 confirmed maxillary incisor pseudo-odontomas, 20 normal mandibular incisors, 12 presumed mandibular incisor pseudo-odontomas). Maxillary incisors with confirmed pseudo-odontomas had a significantly hyperattenuating pulp and dentin in the reserve crown and apical zone, when compared to normal maxillary incisors. Pseudo-odontomas appeared as enlargements of the apical zone with a globular/multilobular hyperattenuating mass formation haphazardly arranged, encroaching on midline and growing caudally and ventrally. Presumed mandibular incisor pseudo-odontomas had similar CT characteristics. In 60% of prairie dogs with maxillary incisor pseudo-odontomas, the hard palate was deformed and the mass bulged into the oral cavity causing loss of the palatine bone. The common nasal meatus was partially or totally obliterated in 81.8% of prairie dogs with maxillary pseudo-odontomas. Findings supported the use of CT for characterizing extent of involvement and surgical planning in prairie dogs with pseudo-odontomas. © 2017 American College of Veterinary Radiology.

  5. Degree of severity of molar incisor hypomineralization and its relation to dental caries

    OpenAIRE

    Negre-Barber, A.; Montiel-Company, J. M.; Catalá-Pizarro, M.; Almerich-Silla, J. M.

    2018-01-01

    Molar incisor hypomineralization is a developmental defect of dental enamel associated with rapid caries progression. In order to discover whether molar incisor hypomineralization predisposes to dental caries, a cross-sectional cohort study was conducted in a sample of 414 children aged between eight and nine years. It was found that 24.2% of the children presented molar incisor hypomineralization. Of these, 72% had a mild form and 28% a severe form. Caries prevalence was greater among the ch...

  6. Treatment strategies for missing maxillary central incisor--an orthodontist's perspective.

    Science.gov (United States)

    Gautam, Rajaganesh; Nene, Purvaja; Mehta, Kunal; Nene, Salil; Hegde, Ashwith; Jaju, Rajbala

    2014-08-01

    The loss of maxillary central incisors at an early age has psychological, esthetic, and functional implications. Multiple treatment options are available for replacing missing central incisors. The management demands a multidisciplinary approach involving the orthodontist, prosthodontist, and periodontist. Treatment planning requires consideration of a variety of clinical and nonclinical factors. This clinical report attempts to demonstrate different strategies for the management of unilaterally and bilaterally missing central incisors. © 2014 by the American College of Prosthodontists.

  7. [Intruding upper incisors using mini-screw anchorage in patients with gummy smile].

    Science.gov (United States)

    Li, Yun-Yi; Zhou, Yan-Heng; Lin, Jiu-Xiang

    2009-08-01

    To evaluate the effectiveness of mini-screw anchorage on intruding upper incisors in patients with gummy smile. Sixteen female patients (mean age: 23.8 years) were involved in this study. The mini-screws were placed between upper lateral incisors and canines on both sides for intruding upper incisors together with fixed appliance. The cephalometric analysis was carried out. Totally 63 teeth in 16 patients were intruded successfully and the deep overbite was decreased by (2.74 +/- 2.00) mm (P gummy smile by intruding upper incisors with mini-screw implant.

  8. Validity of radiographic assessment of ankylosis; Evaluation of long-term reaction in 10 monkey incisors

    Energy Technology Data Exchange (ETDEWEB)

    Stenvik, A. (Oslo Univ. (Norway)); Beyer-Olsen, E.; Aabyholm, F.; Haanaes, H.R.; Gerner, N.W. (Rikshospitalet, Oslo (Norway))

    1990-01-01

    The accuracy and sensitivity of radiographic assessments of reactive processes in dental tissues were evaluated by comparison of radiographs and histologic sections. Experimental lesions inflicted on the roots of 10 monkey incisors had been observed by means of serially obtained radiographs over a period of 315 to 370 days. The material was used for evaluation of radiographic assessment of ankylosis. For comparative purposes, assessment of the experimental lesion penetrating to the pulp and periapical radiolucency was added. True and falsely positive or negative recordings formed the basis for calculation of the accuracy and sensitivity of the radiographic assessment. The sensitivity, or the obsevers ability to detect the actual changes, was high for pulp penetration, intermediate for inflammation, and low for ankylosis. 6 refs., 3 figs., 2 tabs.

  9. Instability timescale for the inclination instability in the solar system

    Science.gov (United States)

    Zderic, Alexander; Madigan, Ann-Marie; Fleisig, Jacob

    2018-04-01

    The gravitational influence of small bodies is often neglected in the study of solar system dynamics. However, this is not always an appropriate assumption. For example, mutual secular torques between low mass particles on eccentric orbits can result in a self-gravity instability (`inclination instability'; Madigan & McCourt 2016). During the instability, inclinations increase exponentially, eccentricities decrease (detachment), and orbits cluster in argument of perihelion. In the solar system, the orbits of the most distant objects show all three of these characteristics (high inclination: Volk & Malhotra (2017), detachment: Delsanti & Jewitt (2006), and argument of perihelion clustering: Trujillo & Sheppard (2014)). The inclination instability is a natural explanation for these phenomena.Unfortunately, full N-body simulations of the solar system are unfeasible (N ≈ O(1012)), and the behavior of the instability depends on N, prohibiting the direct application of lower N simulations. Here we present the instability timescale's functional dependence on N, allowing us to extrapolate our simulation results to that appropriate for the solar system. We show that ~5 MEarth of small icy bodies in the Sedna region is sufficient for the inclination instability to occur in the outer solar system.

  10. Influence of occlusal plane inclination and mandibular deviation on esthetics.

    Science.gov (United States)

    Corte, Cristiane Cherobini Dalla; Silveira, Bruno Lopes da; Marquezan, Mariana

    2015-10-01

    The aim of this study was to assess the degree of perception of occlusal plane inclination and mandibular deviation in facial esthetics, assessed by laypeople, dentists and orthodontists. A woman with 5.88° of inclination and 5.54 mm of mandibular deviation was selected and, based on her original photograph, four new images were created correcting the deviations and creating more symmetric faces and smiles. Examiners assessed the images by means of a questionnaire. Their opinions were compared by qualitative and quantitative analyses. A total of 45 laypeople, 27 dentists and 31 orthodontists filled out the questionnaires. All groups were able to perceive the asymmetry; however, orthodontists were more sensitive, identifying asymmetries as from 4.32° of occlusal plane inclination and 4.155 mm of mandibular deviation (pocclusal plane inclination and 5.54 mm of mandibular deviation (pOcclusal plane inclination and mandibular deviation were perceived by all groups, but orthodontists presented higher perception of deviations.

  11. Method to reduce variations of inclination angle of the acetabular component during mini-incision hip arthroplasty.

    Science.gov (United States)

    Nakamura, Shigeru; Matsuda, Kenta; Arai, Noriyuki; Kobayashi, Makoto; Wakimoto, Nobuhiro; Matsushita, Takashi

    2006-05-01

    To reduce variations of cup inclination after total hip arthroplasty using the mini-incision posterior approach, we introduced two techniques, one at a time. The first technique is measuring a pelvic tilt angle in the frontal plane in the initial lateral position in the operating room. The second technique is using a tilt-meter to adjust the direction of a cup holder. The purpose of this study was to evaluate the usefulness of these techniques. For 106 hips operated on, the cementless acetabular component was impacted using a cup holder targeting 45 degrees in inclination and 20 degrees in anteversion. These hips were divided into three consecutive groups. For the first group (30 hips), no radiograph in the lateral position was obtained, and the alignment frame of the cup holder was aligned parallel to the floor by eye measurement. For the second group (56 hips), we measured the pelvic tilt angle, and tilted the alignment frame by eye measurement. For the third group (20 hips), we measured the pelvic tilt angle and tilted the alignment frame using the tilt meter. Inclination and anteversion angles were measured on postoperative radiographs. The absolute value of the difference between the measured angle and the target angle was defined as the inclination error or anteversion error, respectively. The inclination error was more than 5 degrees for 33% in the first group, 20% in the second group, and 0% in the third group (P = 0.015, chi-squared test). There was a significant difference between the first group and the third group (P = 0.0039). For the anteversion error, there were no significant differences among the three groups. Adjustment using a tilt-meter after measuring a pelvic tilt angle is a useful method to reduce the rate of large inclination error.

  12. Distribution and characteristics of molar-incisor hypomineralization.

    Science.gov (United States)

    Janković, Svjetlana; Ivanović, Mirjana; Davidović, Bojana; Lecić, Jelena

    2014-08-01

    Developmental disorders of teeth are the problems that are becoming more present in pediatric dentistry, especially on first permanent molars and incisors. Molar Incisor Hypomineralization (MIH) is proposed term for this phenomenon. The aim of this study was to establish the MIH prevalence in children living in the Foca municipality (Bosnia and Herzegovina) as well as to assess characteristics and expression of hypomineralization within the tested population. A total of 141 children from the Foca municipality, 8 years of age, were included in this study. Criteria according to Weerhejm have been used for diagnosis of hypomineralization: demarcated opacity (DO), post-eruptive breakdown (PEB), atypical restoration (AR), extracted molars due to MIH (E-MIH) and unerupted tooth (UT). Level and the prominence of color changes have been determined for patients with DO, PEB and AR. MIH in this area was present in 12.8% of children. The prevalence of MIH changes expressed in percentages was as follows: DO was at 9.2%, PEB in 3.5%, AR in 5.6%, while E-MIH was 5.6%. A total of 9.9% of the examinees had mild, 5.6% moderate, and 7.8% severe form of MIH. White form of MIH defects was found in 9.9% of the examinees, white-yellow one in 5.6% and yellow-brown color in 3.5% of the examined children. These changes were more often present in the lower jaw (60.3%). In total, 6.4% of children had these changes present only on molars, while 6.4% of them both on molars and incisors simultaneously. A total of 12.8% of the examinees with MIH is not to be disregarded. With timely diagnosis, prevention and therapy complications could be avoided or mitigated.

  13. Distribution and characteristics of molar-incisor hypomineralization

    Directory of Open Access Journals (Sweden)

    Janković Svjetlana

    2014-01-01

    Full Text Available Background/Aim. Developmental disorders of teeth are the problems that are becoming more present in pediatric dentistry, especially on first permanent molars and incisors. Molar Incisor Hypomineralization (MIH is proposed term for this phenomenon. The aim of this study was to establish the MIH prevalence in children living in the Foča municipality (Bosnia and Herzegovina as well as to assess characteristics and expression of hypomineralization within the tested population. Methods. A total of 141 children from the Foča municipality, 8 years of age, were included in this study. Criteria according to Weerhejm have been used for diagnosis of hypomineralization: demarcated opacity (DO, post-eruptive breakdown (PEB, atypical restoration (AR, extracted molars due to MIH (E-MIH and unerupted tooth (UT. Level and the prominence of color changes have been determined for patients with DO, PEB and AR. Results. MIH in this area was present in 12.8% of children. The prevalence of MIH changes expressed in percentages was as follows: DO was at 9.2%, PEB in 3.5%, AR in 5.6%, while E-MIH was 5.6%. A total of 9.9% of the examinees had mild, 5.6% moderate, and 7.8% severe form of MIH. White form of MIH defects was found in 9.9% of the examinees, white-yellow one in 5.6% and yellow-brown color in 3.5% of the examined children. These changes were more often present in the lower jaw (60.3%. In total, 6.4% of children had these changes present only on molars, while 6.4% of them both on molars and incisors simultaneously. Conclusion. A total of 12.8% of the examinees with MIH is not to be disregarded. With timely diagnosis, prevention and therapy complications could be avoided or mitigated.

  14. Heat transfer coefficient in pool boiling for an electrically heated tube at various inclinations

    International Nuclear Information System (INIS)

    Fahmy, A.S.A.; Mariy, A.H.; Mahmoud, S.I.; Ibrahim, N.A.

    1987-01-01

    An experimental investigation is carried out study the behaviour of heat transfer in pool boiling from a vertical and inclined heated tube at atmospheric pressure. An imperial correlation joining the different parameters affecting the heat transfer coefficient in pool boiling for an electrically heated tube at various inclinations is developed. Two test sections (zircaloy-4 and stainless steel) of 16 n n outer diameter and 120 nm length are investigated. Four levels of heat flux are used for heating the two lest sections (e.g. 381, 518, 721 and 929 k.watt/n 2). The maximum surface temperature achieved is 146.5 degree c for both materials, and the maximum bulk temperature is 95 degree C. It is found that the average heat transfer coefficient is inversely proportional with heated length l, where it reaches a constant value in the horizontal position. The heat transfer coefficient curves at various inclinations with respect to the heated tube length pass around one point which is defined as limit length

  15. Bilateral Complete and Incomplete Fusion of Incisors and its Management.

    Science.gov (United States)

    Da Costa, Godwin Clovis; Chalakkal, Paul; De Souza, Neil; Gavhane, Sanket

    2017-01-01

    This case report highlights the management of a case of bilateral complete and incomplete fusion of maxillary incisors in a 10-year-old child. A mock-up was done on the diagnostic cast. Pretreatment esthetic evaluation was done using bis-acryl composite temporaries which were transferred intraorally from the diagnostic cast using a putty index. An incisal overlap veneer preparation was done, following which, an IPS e-max veneer was cemented. A digital mock-up was carried out using the Adobe Photoshop and Corel Draw softwares to aid in laboratorial fabrication of the veneer.

  16. Bilateral complete and incomplete fusion of incisors and its management

    Directory of Open Access Journals (Sweden)

    Godwin Clovis Da Costa

    2017-01-01

    Full Text Available This case report highlights the management of a case of bilateral complete and incomplete fusion of maxillary incisors in a 10-year-old child. A mock-up was done on the diagnostic cast. Pretreatment esthetic evaluation was done using bis-acryl composite temporaries which were transferred intraorally from the diagnostic cast using a putty index. An incisal overlap veneer preparation was done, following which, an IPS e-max veneer was cemented. A digital mock-up was carried out using the Adobe Photoshop and Corel Draw softwares to aid in laboratorial fabrication of the veneer.

  17. Droplet Depinning on Inclined Surfaces at High Reynolds Numbers

    Science.gov (United States)

    White, Edward; Singh, Natasha; Lee, Sungyon

    2017-11-01

    Contact angle hysteresis enables a sessile liquid drop to adhere to a solid surface when the surface is inclined, the drop is exposed to gas-phase flow, or the drop is exposed to both forcing modalities. Previous work by Schmucker and White (2012.DFD.M4.6) identified critical depinning Weber numbers for water drops subject to gravity- and wind-dominated forcing. This work extends the Schmucker and White data and finds the critical depinning Weber number obeys a two-slope linear model. Under pure wind forcing at Reynolds numbers above 1500 and with zero surface inclination, Wecrit = 8.0 . For non-zero inclinations, α, Wecrit decreases proportionally to A Bo sinα where A is the drop aspect ratio and Bo is its Bond number. The same relationship holds for α behavior. Supported by the National Science Foundation through Grant CBET-1605947.

  18. Natural Frequencies and Mode Shapes of Statically Deformed Inclined Risers

    KAUST Repository

    Alfosail, Feras

    2016-10-15

    We investigate numerically the linear vibrations of inclined risers using the Galerkin approach. The riser is modeled as an Euler-Bernoulli beam accounting for the nonlinear mid-plane stretching and self-weight. After solving for the initial deflection of the riser due to self-weight, we use a Galerkin expansion employing 15 axially loaded beam mode shapes to solve the eigenvalue problem of the riser around the static equilibrium configuration. This yields the riser natural frequencies and corresponding exact mode shapes for various values of inclination angles and tension. The obtained results are validated against a boundary-layer analytical solution and are found to be in good agreement. This constitutes a basis to study the nonlinear forced vibrations of inclined risers.

  19. Psychopathic Inclination Among Incarcerated Youth of Hazara Division Pakistan

    Directory of Open Access Journals (Sweden)

    Sher Dil

    2016-09-01

    Full Text Available Present study aimed at evaluating the psychopathic inclination among youth and finding the gender differences in psychopathy. An indigenously developed Psychopathy scale (Urdu has been used in this study. Alpha reliability of the scale was .90. The study was conducted on 100 males (50 criminals and 50 non-criminals and 100 females (26 criminals and 74 non-criminals using a convenient sampling technique from three districts of Hazara division: Haripur, Abbottabad, and Mansehra. Results confirmed that there is significant difference in psychopathic inclination of males and females; criminals differed significantly from the non-criminals. The study also paves way for further investigation in the field in Pakistan.

  20. Entrepreneurial Inclination Among Business Students: A Malaysian Study

    Directory of Open Access Journals (Sweden)

    Yet-Mee Lim

    2012-10-01

    Full Text Available Entrepreneurship has been the fundamental topics of discussion among the politicians, economists, and academics. Business creation is especially critical in developing countries to stimulate economic growth. The present study attempts to examine entrepreneurial inclination among students who are a potential source of entrepreneurs. The fi ndings of the present research study indicate that majority of our business students are not entrepreneurial-inclined. They do not seem to possess strong entrepreneurial characteristics and entrepreneurial skills, and they are not keen in starting a new business. The roles of higher institutes of education and the government in promoting entrepreneurship are discussed.

  1. Fluorescence intensity dependence on the propagation plane inclination

    International Nuclear Information System (INIS)

    Fernandez, J.E.; Rubio, Marcelo; Sanchez, H.J.

    1987-01-01

    A Monte Carlo simulation of the primary and secondary X-ray fluorescent emission from an homogeneous and infinite thickness sample, irradiated under different inclination of the propagation plane, is carried out. An agreement with the predictions based on Sherman equations depending on the inclination angle α was found. The invariance of the primary fluorescence with respect to α and the decrease until evanescence of the secondary fluorescence for a α → π/2 are confirmed. A discussion about the physical basis of this dependence is carried out. Similar results are expected for tertiary fluorescence. (Author) [es

  2. Orthodontic management of bilateral maxillary canine-first premolar transposition and bilateral agenesis of maxillary lateral incisors: a case report

    Directory of Open Access Journals (Sweden)

    Elena Di Palma

    2015-04-01

    Full Text Available INTRODUCTION: Maxillary canine-first premolar transposition (Mx.C.P1 is an uncommon dental positional anomaly that may create many orthodontic problems from both esthetic and functional points of view. OBJECTIVE: In this report we show the orthodontic management of a case of Mx.C.P1 associated with bilateral maxillary lateral incisor agenesis and unilateral mandibular second premolar agenesis METHODS: The patient was treated with a multibracket appliance and the extraction of the lower premolar. RESULTS: treatment was completed without the need for any prosthetic replacement.

  3. Clinical recommendations for management of mesiodens and unerupted permanent maxillary central incisors.

    Science.gov (United States)

    Ayers, E; Kennedy, D; Wiebe, C

    2014-12-01

    Un-erupted maxillary incisors may result secondary to supernumerary teeth. Despite the removal of such mesiodentes, orthodontic traction of a permanent un-erupted maxillary incisor may be required. The literature regarding the impacted maxillary central incisor(s) was reviewed and all pertinent publications on the subject assessed. The review specifically relative to mesiodentes, surgical exposure and orthodontic management was interpreted together with the clinical experience of a number of the authors' cases. From this analysis a set of recommendations was developed. (1) A sufficient arch space has to be ensured or orthodontically created for permanent maxillary central incisor(s). (2) Early surgical extraction of a mesiodens or mesiodentes (ideally before 7 years of age), with simultaneous closed surgical exposure of the permanent impacted maxillary incisor with bonding of an attachment with gold chain. (3) Re-evaluation after 2-3 months to assess for any natural eruption of the maxillary central incisor. (4) Application of orthodontic traction in the event of non-eruption. Early diagnosis of the presence of mesiodentes is imperative. Appropriate surgical and/or orthodontic traction is often indicated with regular post-surgical follow-up assessments.

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

    Directory of Open Access Journals (Sweden)

    Sergio Paduano

    2014-01-01

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

  5. Multidisciplinary Treatment of Severe Upper Incisor Root Resorption Secondary to Transposed Canine.

    Science.gov (United States)

    Korkmaz, Yasemin Nur; Yagci, Filiz

    2017-02-01

    Tooth transposition is a rare dental anomaly that could lead to undesirable side effects on other teeth. This case report aims to describe the multidisciplinary treatment of a patient with a severely resorbed permanent maxillary central incisor due to transposition with the permanent canine. A girl aged 13 years and 7 months with a chief complaint of a pink spot on her maxillary left incisor with a slightly erupted tooth above it was referred to our clinic. Her left maxillary canine was transposed to her left central incisor site. The left canine was impacted and had caused severe resorption of the left central incisor root. Her maxillary left canine was substituted for the central incisor after the compulsory extraction of her left central incisor. The canine was prosthetically restored after orthodontic treatment. The results were stable 1 year after treatment had been completed. Orthodontic treatment in coordination with other dental specialties like prosthodontics, periodontology and oral and maxillofacial surgery can provide functional and esthetic outcome in cases of severely transposed canines. This is a rare case of transposition that shows the significant root resorption on the maxillary central incisor due to the ectopic eruption of the canine. Canine substitution for the central incisor was chosen as a treatment plan instead of placing an implant. An esthetic smile and a functional occlusion were established at the end of the treatment. (J Esthet Restor Dent 29:5-12, 2017). © 2016 Wiley Periodicals, Inc.

  6. Intrusion of Lower Incisors in Deep Overbite Cases with Mini-screws.

    Science.gov (United States)

    Alaa-Eldin, Ahmed M; Salem, Ahmed S; Fouda, Maher A

    2016-01-01

    To evaluate the dentoskeletal effects of intrusion of the lower incisor teeth by mini-screws. Ten patients were selected from the outpatient clinic of the Department of Orthodontics, Faculty of Dentistry, Mansoura University with Angle's Class II division I malocclusions. Age ranged from 15 to 18 years (15.4 year mean) with deep overbite (more than 1/3 the crown height of the lower incisors covered) requiring intrusion of the lower incisors. After alignment of the first molars, the second premolars ,and canines without inclusion of the lower four incisors, the cuspids were retracted on 16x22 inch stainless steel wire. For each patient, two mini-screws were inserted for anchorage for the lower incisors segment intrusion between the lateral incisor and the cuspid--one in each side and connected to a utility arch wire. The mean of overbite correction was 4.2 mm (p<. 05, and lower incisors were intruded significantly by a mean of 3.55 mm (p<.05). The mandibular incisors were effectively intruded by using mini-screws as orthodontic anchorage with no significant counteractive movements in the molars.

  7. Diagnostic performance of increased overjet in Class II division 1 malocclusion and incisor trauma.

    Science.gov (United States)

    Baccetti, Tiziano; Giuntini, Veronica; Vangelisti, Andrea; Darendeliler, M Ali; Franchi, Lorenzo

    2010-01-01

    The objectives of this study were: 1) to evaluate the associations between an increased overjet (IO) and other dentoskeletal characteristics of Class II division 1 malocclusions in the mixed dentition; 2) to assess whether Class II division 1 malocclusions or rather an increased overjet per se is a risk factor for upper incisor trauma (UIT). A sample of 900 mixed dentition subjects, was observed by clinical inspection, analysis of dental casts, and lateral cephalograms. The diagnostic performance of IO (overjet ≥ 7 mm) was evaluated in relation to other Class II dentoskeletal features (Class II molar and canine relationships, and skeletal Class II relationships). Secondly, the diagnostic performance of IO and of the other Class II dentoskeletal components was tested with regard to the prevalence of UIT. Diagnostic performance was assessed by odds ratio and positive likelihood ratio. The diagnostic performance of IO with regard to the other dentoskeletal components of Class II malocclusions was not significant. The only Class II features associated significantly with an increased risk of UIT was IO. When used as an isolated occlusal feature, IO is not a valid diagnostic indicator for Class II division 1 malocclusions. An increased overjet per se, and not Class II malocclusions, appears to be a significant risk factor for UIT. These findings recommend discrimination between clinical conditions showing an isolated IO from comprehensive Class II malocclusions during diagnosis, analysis of treatment outcomes, and evaluation of the risk of upper incisor trauma. Copyright © 2010 Società Italiana di Ortodonzia SIDO. Published by Elsevier Srl. All rights reserved.

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

    Science.gov (United States)

    Pavuluri, Chaitanya; Nuvvula, Sivakumar

    2013-01-01

    Maxillary incisors are the most frequently injured teeth in the primary and permanent dentition. Stage of adolescence show a significant number of dental injuries as they engage in contact sports. Children with accident prone profile, i.e. class II division I or class I type II malocclusion are more prone for injuries because of the proclined maxillary incisors. Supernumerary teeth are those that are additional to the normal complement. They occur in single or multiple, unilateral or bilateral in either of the jaws. This paper reports the presence of an inverted supernumerary tooth in the right maxillary central incisor region with trauma involving both maxillary central incisors and also the management of the supernumerary tooth and traumatized teeth in a 14-year-old boy. How to cite this article: Pavuluri C, Nuvvula S. Management of Traumatic Injury to Maxillary Central Incisors associated with Inverted Mesiodens: A Case Report. Int J Clin Pediatr Dent 2013;6(1):30-32.

  9. Management of a Permanent Maxillary Lateral Incisor with Vital Pulp and Necrotic Dens Invaginatus Type III.

    Science.gov (United States)

    Soares, Thais Rodrigues Campos; Silva, Luciana Pereira da; Andrade Risso, Patrícia de; Maia, Lucianne Cople; Primo, Laura Guimarães

    2017-09-15

    This is a case report on the management of a vital lateral incisor with a radiolucent cervical area associated with the presence of necrotic pulp due to a dens invaginatus (DI) type III. A nine-year-old boy presented to a university pediatric dental clinic with dental trauma. The examination showed poor oral hygiene, an uncomplicated fracture in the permanent maxillary left central incisor, and a fistula near the permanent maxillary right lateral incisor. A radiograph showed that the right lateral incisor had incomplete root development and a type III DI. Although sensitive to thermal pulp testing, tracing of the fistula indicated that the radiolucent area was associated with the DI, extending laterally to the periodontal ligament. Endodontic treatment was performed only in the invagination, keeping the root canal of the lateral incisor vital. After two years of follow-up, complete root formation and injury repair associated with invagination were observed.

  10. Removable thermoplastic appliances modified by incisal cuts show altered biomechanical properties during tipping of a maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Phillipp Brockmeyer

    2017-08-01

    Full Text Available Abstract Background The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs, modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction. Methods Forty-five RTAs from three different materials (Biolon®, Erkodur®, Ideal Clear® of the same thickness (1 mm were used. Analysis was performed on a separated maxillary central incisor which was part of a resin model with a complete dentition. In 15 RTAs, of different material, a cut was inserted at the incisal edge of tooth 11. In 15 other appliances, the cut was extended to teeth 12 and 21. Fifteen aligners remained uncut. The experimental tooth was tipped starting from the zero position in 0.05° steps to a maximal deflection of ± 0.42° of the incisal edge in vestibular and palatal direction, after positioning the RTA onto the model. Results The horizontal (Fx and the vertical (Fz force components were decreased by approximately half with increasing cut size. Fz values changed during palatal tipping from a weak intrusive force, for aligners without cut, to an extrusive force with increasing cut size. Compared to both other materials used (Erkodur® and Ideal Clear®, the Biolon® aligners showed significantly higher Fx and Fz values (p < 0.0001, respectively. Conclusions RTAs modified by different sized incisal cuts show altered biomechanical properties and an inversion of the vertical force component, during tipping of a maxillary central incisor.

  11. Removable thermoplastic appliances modified by incisal cuts show altered biomechanical properties during tipping of a maxillary central incisor.

    Science.gov (United States)

    Brockmeyer, Phillipp; Kramer, Katharina; Böhrnsen, Florian; Gruber, Rudolf Matthias; Batschkus, Sarah; Rödig, Tina; Hahn, Wolfram

    2017-08-28

    The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs), modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction. Forty-five RTAs from three different materials (Biolon®, Erkodur®, Ideal Clear®) of the same thickness (1 mm) were used. Analysis was performed on a separated maxillary central incisor which was part of a resin model with a complete dentition. In 15 RTAs, of different material, a cut was inserted at the incisal edge of tooth 11. In 15 other appliances, the cut was extended to teeth 12 and 21. Fifteen aligners remained uncut. The experimental tooth was tipped starting from the zero position in 0.05° steps to a maximal deflection of ± 0.42° of the incisal edge in vestibular and palatal direction, after positioning the RTA onto the model. The horizontal (Fx) and the vertical (Fz) force components were decreased by approximately half with increasing cut size. Fz values changed during palatal tipping from a weak intrusive force, for aligners without cut, to an extrusive force with increasing cut size. Compared to both other materials used (Erkodur® and Ideal Clear®), the Biolon® aligners showed significantly higher Fx and Fz values (p < 0.0001, respectively). RTAs modified by different sized incisal cuts show altered biomechanical properties and an inversion of the vertical force component, during tipping of a maxillary central incisor.

  12. Aqua/Aura Inclination Adjust Maneuver Series Spring 2018 Planning

    Science.gov (United States)

    Trenholme, Elena; Boone, Spencer

    2017-01-01

    This will be presented at the International Earth Science Constellation Mission Operations Working Group meeting on December 6-8, 2017 to discuss the Aqua/Aura Spring 2018 Inclination Adjust Maneuver series planning. Presentation has been reviewed and approved by Eric Moyer, ESMO (Earth Science Mission Operations) Deputy Project Manager.

  13. MEASUREMENTS OF DUST EXTINCTION IN HIGHLY INCLINED SPIRAL GALAXIES

    NARCIS (Netherlands)

    JANSEN, RA; KNAPEN, JH; BECKMAN, JE; PELETIER, RF; HES, R

    1994-01-01

    We study the extinction properties of dust in the well-defined dust lanes of four highly inclined galaxies, using U-, B-, V-, R- and I-band CCD and J- and K'-band near-infrared array images. For three of these galaxies, we could use the symmetry of the underlying light profile to obtain absolute

  14. Motion on an Inclined Plane and the Nature of Science

    Science.gov (United States)

    Pendrill, Ann-Marie; Ekström, Peter; Hansson, Lena; Mars, Patrik; Ouattara, Lassana; Ryan, Ulrika

    2014-01-01

    Friction is an important phenomenon in everyday life. All children are familiar with playground slides, which may thus be a good starting point for investigating friction. Motion on an inclined plane is a standard physics example. This paper presents an investigation of friction by a group of 11-year olds. How did they plan their investigations?…

  15. Evidences of inclined transpression at the contact between ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 125; Issue 5. Evidences of inclined ... a right lateral strike-slip component. As a whole, it is suggested that Udayagiri group is thrusted over Vinjamuru group along a westerly dipping thrust plane with a right lateral strike-slip motion and simultaneous E–W contraction.

  16. Inclined Planes and Motion Detectors: A Study of Acceleration.

    Science.gov (United States)

    Tracy, Dyanne M.

    2001-01-01

    Presents an activity in which students work in cooperative groups and roll balls down inclined planes, collect data with the help of an electronic motion detector, and represent data with a graphing calculator to explore concepts such as mass, gravity, velocity, and acceleration. (Contains 12 references.) (Author/ASK)

  17. The effect of circular bridge piers with different inclination angles ...

    Indian Academy of Sciences (India)

    c Indian Academy of Sciences. The effect of circular bridge piers with different inclination angles toward downstream on scour. MOHAMMAD VAGHEFI1,∗, MASOUD GHODSIAN2 and. SAEID SALIMI3. 1Department of Civil Engineering, Persian Gulf University, Shahid Mahini Street, P.O. Box: 75169-13817,. Bushehr, Iran.

  18. The inter-relationships between angle of inclination, height and ...

    African Journals Online (AJOL)

    Experiments were conducted to investigate the dependence of number of sprouted teak (Tectona grandis Linn. F) stumps on the height above root collar and angle of inclination of planted teak stumps. The studies were aim-ed at developing suitable methods of converting teak seedlings into stumps and planting practices to ...

  19. Reconstruction of Galileo Galilei's Experiment: The Inclined Plane

    Science.gov (United States)

    Straulino, S.

    2008-01-01

    In the "Third Day" of the "Discourses and Mathematical Demonstrations Concerning Two New Sciences" Galileo Galilei describes the famous experiment of the inclined plane and uses it to bring an experimental confirmation to the laws of uniformly accelerated motion. We describe a reconstruction of the experiment and how the results can be used for…

  20. Optimization of PV array inclination in India using ANN estimator ...

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana; Volume 40; Issue 5. Optimization of PV array inclination in India using ANN estimator: Method comparison study ... Although different non-linear, empirical models have been proposed by different researchers in India, they have too many constraints and needs complex and rigorous computational ...

  1. A layered model for inclined pipe flow of settling slurry

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Václav; Krupička, Jan; Kesely, Mikoláš

    2018-01-01

    Roč. 333, June (2018), s. 317-326 ISSN 0032-5910 R&D Projects: GA ČR GA17-14271S Institutional support: RVO:67985874 Keywords : inclined pipe * settling slurry * pressure drop * flow stratification * laboratory loop Impact factor: 2.942, year: 2016

  2. Evidences of inclined transpression at the contact between ...

    Indian Academy of Sciences (India)

    zone may show different structures or dominance of certain type of structures, depending on whether that part is dominated by strike-slip, dip slip or compression. The present study finds evidences of inclined transpression at the contact between. Udayagiri and Vinjamuru group of NSB, which is the main focus of this paper.

  3. Dilaceration of Mandibular Central Incisor: a case report

    Directory of Open Access Journals (Sweden)

    Senem Yigit Ozer

    2011-01-01

    Full Text Available Dilaceration of teeth can ocur as a result of trauma to its primary predecessors. Crown dilaceration is more rare than root dilacerations. This report describes a rare case of crown dilaceration of the mandibular central incisor caused by trauma. Periapical radiography and cone beam computed tomography scans revealed a severe crown dilaceration in the labial direction. After conventional root canal treatment, a glass fiber-reinforced post was placed and the tooth was restored using the original crown which was removed from the root before root canal obturation. One year after the treatment, the tooth was clinically intact without mobility and there was no sensitivity during percussion. Radiographic examination revealed that the periodontal tissues were healthy and there was no sign of root resorption. It was concluded that correct diagnosis and prompt treatment help to achieve desirable esthetics and function for crown dilecaration.

  4. Dens invaginatus in a geminated maxillary lateral incisor

    Science.gov (United States)

    Pallivathukal, Renjith George; Misra, Alok; Nagraj, Sumanth Kumbargere; Donald, Preethy Mary

    2015-01-01

    Dens invaginatus (DI) and gemination are two developmental abnormalities that are well reported in the dental literature, but their coexistence in a single tooth is rare. Such situations worsen the risk factors associated with these anomalies, and the treatment plan should be customised as they possess altered morphology and anatomy. A 19-year-old girl came for evaluation of a cracked tooth in the front region of the upper jaw. The tooth showed clinical features of gemination and radiographic features of DI, and was diagnosed as DI in geminated maxillary lateral incisor. The differential diagnoses based on clinical appearance without radiographic investigation may warrant the treatment approach if these two abnormalities coexist in a single tooth. The report also highlights the importance of three-dimensional imaging in diagnosis and treatment planning of teeth with altered pulp canal anatomy. There are few reported cases in the literature detailing the treatment options for these two anomalies occurring in the same tooth. PMID:26002668

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

    Science.gov (United States)

    Gotler, M; Ratson, T

    2010-04-01

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

  6. Molar incisor hypomineralization in Hong Kong Chinese children.

    Science.gov (United States)

    Cho, Shiu-Yin; Ki, Yung; Chu, Vanessa

    2008-09-01

    Most prevalence studies on molar incisor hypomineralization (MIH) were carried out in European countries, and data from the East-Asian populations were lacking. This study aimed to investigate the prevalence of MIH in Hong Kong Chinese children. Since 2006, charting of teeth with MIH was included into the routine dental examination in a school dental clinic. The dental records of grade 6 primary school children who attended annual check-up in this clinic in 2006 were subsequently reviewed retrospectively. The records were selected for this study if the charting indicated that the children were affected by MIH. A total of 2635 records were reviewed and 73 cases of MIH were identified. The prevalence of MIH in this group of children was 2.8%. Their mean age was 12, and the male-to-female ratio was 1 : 1.2. The mean decayed, missing, or filled permanent teeth value of those affected was 1.5, which was higher than that of the general Hong Kong Chinese children aged 12 years old (0.8). A total of 192 teeth were affected. The most commonly affected teeth were permanent maxillary first molars, followed by mandibular first molars and maxillary central incisors. Dental fillings and fissure sealants were found in 52 (38%) and 65 (47%) permanent first molars with hypomineralization, respectively. Medical histories were unremarkable in 60 children, whereas early childhood diseases were reported in 13 cases. The prevalence of MIH in the permanent dentition of Hong Kong Chinese children was 2.8%. Children with MIH showed higher caries experience in the permanent dentition than the general population of similar age.

  7. Analysis of the golden proportion and width/height ratios of maxillary anterior dentition in patients with lateral incisor agenesis.

    Science.gov (United States)

    Pini, Núbia Pavesi; de-Marchi, Luciana Manzotti; Gribel, Bruno Frazão; Ubaldini, Adriana Lemos Mori; Pascotto, Renata Corrêa

    2012-12-01

      The purpose of this study was to assess the presence of the golden proportion (GP) in the facial view tooth-to-tooth width proportion of the six maxillary anterior teeth and to evaluate the width/height (W/H) ratios of the incisors of patients with maxillary lateral incisor (LI) agenesis treated either with implants or orthodontically (by moving canines into the position of the laterals, recontouring them, and placing composite restorations over the repositioned teeth).   Forty-eight patients with LI agenesis were divided into four experimental groups: unilateral recontouring group (N = 10), bilateral recontouring group (BRG, N = 18), unilateral implant group (UIG, N = 10), bilateral implant group (N = 10), and a control group (CG, N = 25) of patients without agenesis. GP ratios were determined on patients' dental casts placed over Levin's grids, whereas W/H ratios were measured directly on the casts and a millimeter ruler to determine these distances. Statistical analysis was performed with Shapiro-Wilk, Kruskal-Wallis, Mann-Whitney, Friedman, and Wilcoxon tests (p agenesis, regardless of the method of treatment. The mean W/H ratios of the laterals ranged between 0.75 and 0.90.   Although the GP may be a useful diagnostic guide, it was not observed in the majority of esthetic outcomes of patients treated with maxillary LI agenesis in this study. The assessment of the golden proportion and width/height ratio of upper anterior teeth in patients with upper lateral incisor agenesis treated with either implants or tooth re-contouring may assist dentists and patients in deciding the best treatment option based on the peculiarities of each case. © 2012 Wiley Periodicals, Inc.

  8. Natural convection in inclined hemispherical cavities with isothermal disk and dome faced downwards. Experimental and numerical study

    International Nuclear Information System (INIS)

    Baïri, A.; Monier-Vinard, E.; Laraqi, N.; Baïri, I.; Nguyen, M.N.; Dia, C.T.

    2014-01-01

    The objective of this work is to propose correlations of Nusselt–Rayleigh type for controlling the thermal state of electronic devices used in various engineering sectors such as thermoregulation of electronic devices, solar energy, aeronautics or safety and security. The assemblies are contained in hemispherical air-filled cavities whose disk is maintained isothermal and inclined at an angle varying between 90° (vertical position) and 180° (disk horizontal with isothermal dome oriented downwards). The numerical approach performed by means of the finite volume method for Rayleigh numbers varying between 10 4 and 5 × 10 8 is validated by measurements for various combinations of inclination angle and Rayleigh number. The results of this work show that the natural convective heat transfer are between 13% and 21% higher when the disk is maintained isothermal as compared to the case corresponding to imposed heat flux on the disk, for the same inclination angle and Rayleigh ranges. - Highlights: • Quantification of steady state natural convective heat transfer. • Nu–Ra correlations for large Ra range and Dirichlet-type boundary condition. • Hemispherical air-filled inclined enclosure with dome oriented downwards. • Thermal control of electronic devices for engineering applications. • Experimental and numerical approaches

  9. Association of agenesis of mandibular lateral incisors with other dental anomalies in a Japanese population.

    Science.gov (United States)

    Endo, Saori; Sanpei, Sugako; Takakuwa, Akiko; Takahashi, Keiko; Endo, Toshiya

    2013-01-01

    The purpose of this study was to explore the association of mandibular incisor agenesis with other dental anomalies in Japanese orthodontic patients. A total of 52 subjects with 1 or 2 congenitally missing permanent mandibular lateral incisors (group A) were selected and divided into group 1a (26 subjects with 1 lateral incisor missing) and group 2a (26 subjects with 2 lateral incisors missing). Fifty two sex-matched subjects without agenesis of the mandibular lateral incisor served as controls (group C). Radiographs, study models, and medical and dental records were used to identify anomalies of teeth. The prevalence rate of agenesis of teeth other than the mandibular lateral incisors and third molars was significantly increased in group A. Agenesis of the maxillary second premolars was significantly increased in groups 2a and A. Significantly increased prevalence rates of symmetrical tooth agenesis, with third molars excluded, and third molar agenesis were observed in group 1a and A. Japanese subjects with agenesis of 1 or 2 permanent mandibular lateral incisors have significantly increased prevalence rates of other permanent tooth agenesis and symmetrical tooth agenesis.

  10. Management of impacted incisors following surgery to remove obstacles to eruption: a prospective clinical trial.

    Science.gov (United States)

    Pavoni, Chiara; Franchi, Lorenzo; Laganà, Giuseppina; Baccetti, Tiziano; Cozza, Paola

    2013-01-01

    The purpose of this study was to assess the effectiveness of rapid maxillary expansion (RME) vs simply monitoring the eruption of permanent maxillary incisors following the surgical removal of obstacles to their eruption (supernumerary teeth, odontomas). Following surgical removal of the obstacles to incisor eruption (T1), 62 patients were randomly assigned to either the group to undergo RME (34 subjects; mean age 8 years, 11 months ± 11 months) or the group that was monitored without further treatment (28 subjects; mean age=9 years, 1 month ± 1 year). At T2 (1 year after T1), the prevalence rate of erupted incisors was recorded. Also, the time of eruption of the incisors and the amount of space loss were analyzed. At T2, eruption of impacted incisors occurred in approximately 82 percent of the RME group cases vs approximately 39 percent of the monitored group cases (chi-square=10.43, P<.001). Time of eruption was significantly faster in the RME group, and anterior space loss significantly smaller. Rapid maxillary expansion treatment following surgical removal of the obstacles to the eruption of permanent maxillary incisors appears to be an efficient interceptive approach leading to eruption of the incisors in four out of five cases within seven months.

  11. Lower incisor intrusion with intraoral transosseous stainless steel wire anchorage in rabbits.

    Science.gov (United States)

    Wu, Jian-chao; Huang, Ji-na; Lin, Xin-ping

    2010-06-01

    The purpose of this research was to investigate the potential use of intraoral transosseous stainless steel wires as anchorage for intrusion of the lower incisors using a rabbit model. Placement of intraoral transosseous stainless steel wires around incisors is similar to that of intraoral transosseous wiring of edentulous mandibular fractures. Ten male New Zealand rabbits, 9 +/- 1.5 months of age, average weight 1.8 +/- 0.3 kg, were used in this study. One lower incisor was intruded with a 50 g bilateral force using a coil spring for 10 weeks, while the other incisor served as the control. Clinical measurements of the distances between the occlusal edges of the incisors (EE) were performed weekly with a calliper. In addition to standard descriptive statistical calculations, a paired Student's t-test was used for comparison of the two groups. All surgical sites healed uneventfully after insertion of the wires. Significant differences were found in the change of EE between the experimental and control sides from 4 weeks onwards. Intrusion of the incisor, 4 +/- 0.58 mm, was seen on the test side, while EE on the control side remained unchanged. Within the limits of this animal study, it is concluded that the intraoral transosseous stainless steel wire anchorage system is a cost-effective method for intrusion of lower incisors when the use of other anchorage system is not possible.

  12. Degree of severity of molar incisor hypomineralization and its relation to dental caries.

    Science.gov (United States)

    Negre-Barber, A; Montiel-Company, J M; Catalá-Pizarro, M; Almerich-Silla, J M

    2018-01-19

    Molar incisor hypomineralization is a developmental defect of dental enamel associated with rapid caries progression. In order to discover whether molar incisor hypomineralization predisposes to dental caries, a cross-sectional cohort study was conducted in a sample of 414 children aged between eight and nine years. It was found that 24.2% of the children presented molar incisor hypomineralization. Of these, 72% had a mild form and 28% a severe form. Caries prevalence was greater among the children with severe form (60.7%) than in those with mild form (43.1%) or no molar incisor hypomineralization (45.5%). The caries indices were higher in out molar incisor hypomineralization (1.18) or with mild form (1.08). The tooth-surface caries ratio was significantly higher in surfaces with severe hypomineralization than in those with no hypomineralization or mild hypomineralization. A linear regression model showed that cariogenic food intake and the presence of severe molar incisor hypomineralization were significantly associated with DMFS. Consequently, an association was found to exist between dental caries and the presence of surfaces affected by severe molar incisor hypomineralization, which should be considered a risk factor within the multifactorial etiology of caries.

  13. Spectrum of 100-kyr glacial cycle: orbital inclination, not eccentricity.

    Science.gov (United States)

    Muller, R A; MacDonald, G J

    1997-08-05

    Spectral analysis of climate data shows a strong narrow peak with period approximately 100 kyr, attributed by the Milankovitch theory to changes in the eccentricity of the earth's orbit. The narrowness of the peak does suggest an astronomical origin; however the shape of the peak is incompatible with both linear and nonlinear models that attribute the cycle to eccentricity or (equivalently) to the envelope of the precession. In contrast, the orbital inclination parameter gives a good match to both the spectrum and bispectrum of the climate data. Extraterrestrial accretion from meteoroids or interplanetary dust is proposed as a mechanism that could link inclination to climate, and experimental tests are described that could prove or disprove this hypothesis.

  14. Entrepreneurial Inclination Among Business Students: A Malaysian Study

    Directory of Open Access Journals (Sweden)

    Yet-Mee Lim

    2012-11-01

    Full Text Available Normal 0 false false false IN X-NONE AR-SA MicrosoftInternetExplorer4 Entrepreneurship has been the fundamental topics of discussion among the politicians, economists, and academics. Business creation is especially critical in developing countries to stimulate economic growth. The present study attempts to examine entrepreneurial inclination among students who are a potential source of entrepreneurs. The fi ndings of the present research study indicate that majority of our business students are not entrepreneurial-inclined. They do not seem to possess strong entrepreneurial characteristics and entrepreneurial skills, and they are not keen in starting a new business. The roles of higher institutes of education and the government in promoting entrepreneurship are discussed.

  15. A new understanding of oral and dental disorders of the equine incisor and canine teeth.

    Science.gov (United States)

    Earley, Edward; Rawlinson, Jennifer T

    2013-08-01

    This article discusses the classification systems for dental fractures and how the assessment affects treatment options. Diagonal incisor malocclusion is discussed in relation to skull asymmetry and how this commonly relates to premolar and molar occlusion. Oral and radiographic assessment of incisive bone fracture and incisor avulsion is reviewed for determining treatment options. A summary of incisor and canine resorption and hypercementosis is presented. Clinical presentations, staging, and classifications of tooth resorption as well as canine odontoplasty are discussed. Excessive plaque and calculus formation on lower canines leading to periodontal disease and abscess is examined. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Advances in the treatment of diseased equine incisor and canine teeth.

    Science.gov (United States)

    Rawlinson, Jennifer T; Earley, Edward

    2013-08-01

    Dental therapies for equid incisor and canine teeth have modernized significantly over the last 2 decades. Basic principles in incisor reduction have become more conservative, and extraction procedures more exacting. Periodontal and endodontic treatments are described to save teeth that would have succumbed to extraction in the past. Pathologic impacts on treatment decisions for equine odontoclastic tooth resorption and hypercementosis are significant, and veterinarians and owners need to be aware of treatment options and outcomes. Easy access to equid incisor and canine teeth offers a variety of therapeutic options, and this article reviews some of the practical procedures available. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Endodontic Treatment of Type II Dens Invaginatus in a Maxillary Lateral Incisor: A Case Report

    Science.gov (United States)

    Helvacioglu-Yigit, Dilek; Aydemir, Seda

    2012-01-01

    Dens invaginatus is a developmental anomaly that results in an enamel-lined cavity intruding into the crown or root before the mineralization phase. It typically affects permanent maxillary lateral incisors, central incisors, and premolars. This paper describes the root canal treatment of Oehlers' type II dens invaginatus in maxillary left lateral incisors. A 16-year-old boy presented to the Faculty of Dentistry, University of Kocaeli, to receive his dental treatments. During the caries removal, the pulp was exposed then anendodontic treatment was initiated. Two canals, one of which represented the invagination, were instrumented, irrigated, and then obturated with a lateral condensation technique. PMID:23213576

  18. Endodontic Treatment of Type II Dens Invaginatus in a Maxillary Lateral Incisor: A Case Report

    Directory of Open Access Journals (Sweden)

    Dilek Helvacioglu-Yigit

    2012-01-01

    Full Text Available Dens invaginatus is a developmental anomaly that results in an enamel-lined cavity intruding into the crown or root before the mineralization phase. It typically affects permanent maxillary lateral incisors, central incisors, and premolars. This paper describes the root canal treatment of Oehlers’ type II dens invaginatus in maxillary left lateral incisors. A 16-year-old boy presented to the Faculty of Dentistry, University of Kocaeli, to receive his dental treatments. During the caries removal, the pulp was exposed then anendodontic treatment was initiated. Two canals, one of which represented the invagination, were instrumented, irrigated, and then obturated with a lateral condensation technique.

  19. Overjet and overbite analysis during the eruption of the upper permanent incisors.

    Science.gov (United States)

    Cuoghi, Osmar A; Sella, Rodrigo C; Mamede, Igo; de Macedo, Fernanda A; Miranda-Zamalloa, Yésselin M; de Mendonça, Marcos R

    2009-01-01

    ABSTRACT The purpose of this study was to analyze the overjet and overbite behavior during eruption of the upper permanent incisors. Fourth-eight plaster casts of 16 patients from ages 6-13 years were appraised longitudinally. It was found that the overjet remains constant, starting at the eruption of the upper permanent central incisors until eruption of the upper permanent canine teeth, while the overbite increases after eruption of the upper permanent lateral incisors and remains constant with the eruption of the canine teeth.

  20. A CLINICAL CASE OF LOSS OF THE UPPER LATERAL INCISORS AS A RESULT OF CANINES IMPACTION.

    Directory of Open Access Journals (Sweden)

    Hristina Arnautska

    2014-03-01

    Full Text Available The resorption of the lateral incisors after ectopic eruption of the permanent canines is one of the most common complications and may be detected in all cases of seriously altered route of eruption. The case presented is of a 10-year old boy with permanent dentition and extracted upper lateral incisors as a result of a severe degree of resorption of their roots due to improper eruption of the canines. This article aims at establishing that early detection and prompt preventive measures will lead to avoiding the critical complications arising out of the impacted canines and will preserve the morphological and functional integrity of the incisors and the dentition.

  1. Aqua/Aura Updated Inclination Adjust Maneuver Performance Prediction Model

    Science.gov (United States)

    Boone, Spencer

    2017-01-01

    This presentation will discuss the updated Inclination Adjust Maneuver (IAM) performance prediction model that was developed for Aqua and Aura following the 2017 IAM series. This updated model uses statistical regression methods to identify potential long-term trends in maneuver parameters, yielding improved predictions when re-planning past maneuvers. The presentation has been reviewed and approved by Eric Moyer, ESMO Deputy Project Manager.

  2. Graphs and matroids weighted in a bounded incline algebra.

    Science.gov (United States)

    Lu, Ling-Xia; Zhang, Bei

    2014-01-01

    Firstly, for a graph weighted in a bounded incline algebra (or called a dioid), a longest path problem (LPP, for short) is presented, which can be considered the uniform approach to the famous shortest path problem, the widest path problem, and the most reliable path problem. The solutions for LPP and related algorithms are given. Secondly, for a matroid weighted in a linear matroid, the maximum independent set problem is studied.

  3. Drop impact and rebound dynamics on an inclined superhydrophobic surface.

    Science.gov (United States)

    Yeong, Yong Han; Burton, James; Loth, Eric; Bayer, Ilker S

    2014-10-14

    Due to its potential in water-repelling applications, the impact and rebound dynamics of a water drop impinging perpendicular to a horizontal superhydrophobic surface have undergone extensive study. However, drops tend to strike a surface at an angle in applications. In such cases, the physics governing the effects of oblique impact are not well studied or understood. Therefore, the objective of this study was to conduct an experiment to investigate the impact and rebound dynamics of a drop at various liquid viscosities, in an isothermal environment, and on a nanocomposite superhydrophobic surface at normal and oblique impact conditions (tilted at 15°, 30°, 45°, and 60°). This study considered drops falling from various heights to create normal impact Weber numbers ranging from 6 to 110. In addition, drop viscosity was varied by decreasing the temperature for water drops and by utilizing water-glycerol mixtures, which have similar surface tension to water but higher viscosities. Results revealed that oblique and normal drop impact behaved similarly (in terms of maximum drop spread as well as rebound dynamics) at low normal Weber numbers. However, at higher Weber numbers, normal and oblique impact results diverged in terms of maximum spread, which could be related to asymmetry and more complex outcomes. These asymmetry effects became more pronounced as the inclination angle increased, to the point where they dominated the drop impact and rebound characteristics when the surface was inclined at 60°. The drop rebound characteristics on inclined surfaces could be classified into eight different outcomes driven primarily by normal Weber number and drop Ohnesorge numbers. However, it was found that these outcomes were also a function of the receding contact angle, whereby reduced receding angles yielded tail-like structures. Nevertheless, the contact times of the drops with the coating were found to be generally independent of surface inclination.

  4. Two Mechanisms of Sensorimotor Set Adaptation to Inclined Stance

    Directory of Open Access Journals (Sweden)

    Kyoung-Hyun Lee

    2017-10-01

    Full Text Available Orientation of posture relative to the environment depends on the contributions from the somatosensory, vestibular, and visual systems mixed in varying proportions to produce a sensorimotor set. Here, we probed the sensorimotor set composition using a postural adaptation task in which healthy adults stood on an inclined surface for 3 min. Upon returning to a horizontal surface, participants displayed a range of postural orientations – from an aftereffect that consisted of a large forward postural lean to an upright stance with little or no aftereffect. It has been hypothesized that the post-incline postural change depends on each individual’s sensorimotor set: whether the set was dominated by the somatosensory or vestibular system: Somatosensory dominance would cause the lean aftereffect whereas vestibular dominance should steer stance posture toward upright orientation. We investigated the individuals who displayed somatosensory dominance by manipulating their attention to spatial orientation. We introduced a distraction condition in which subjects concurrently performed a difficult arithmetic subtraction task. This manipulation altered the time course of their post-incline aftereffect. When not distracted, participants returned to upright stance within the 3-min period. However, they continued leaning forward when distracted. These results suggest that the mechanism of sensorimotor set adaptation to inclined stance comprises at least two components. The first component reflects the dominant contribution from the somatosensory system. Since the postural lean was observed among these subjects even when they were not distracted, it suggests that the aftereffect is difficult to overcome. The second component includes a covert attentional component which manifests as the dissipation of the aftereffect and the return of posture to upright orientation.

  5. Determination of angle of inclination for optimum power production ...

    African Journals Online (AJOL)

    This study evaluates the performance of the photovoltaic modules at different tilt angle (angle of inclination) from 5º to 90º. The solar panel of 45 Watts capacity was placed on the manual tracker between the hours of 7:00am and 6:15pm on the geographical location of latitude of 40 55' 58” North and longitude of 60 59' 55” ...

  6. Sagittal x-ray beam deviation at asymmetric inclined diffractors

    Czech Academy of Sciences Publication Activity Database

    Korytár, D.; Hrdý, Jaromír; Artemiev, Nikolai; Ferrari, C.; Freund, A.

    2001-01-01

    Roč. 8, - (2001), s. 1136-1139 ISSN 0909-0495 R&D Projects: GA MŠk OK 305; GA MPO PZ-CH/22 Institutional research plan: CEZ:AV0Z1010914 Keywords : x-ray optics * Si(111) W/grooved crystals * inclined diffraction * out-of-diffraction-plane beams * sagittal focusing Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.519, year: 2001

  7. Does Andrews facial analysis predict esthetic sagittal maxillary position?

    Science.gov (United States)

    Resnick, Cory M; Daniels, Kimberly M; Vlahos, Maryann

    2018-04-01

    Cephalometric analyses have limited utility in planning maxillary sagittal position for orthognathic surgery. In Six Elements of Orofacial Harmony, Andrews quantified maxillary position relative to forehead projection and angulation and proposed an ideal relationship. The purpose of this study was to investigate the ability of this technique to predict esthetic sagittal maxillary position. Survey study including a male and female with straight facial profiles, normal maxillary incisor angulations, and Angle's Class I. Maxillary position was modified on lateral photographs to create 5 images for each participant with incisor-goal anterior limit line (GALL) distances of -4, -2, 0, +2, and +4 mm. A series of health care professionals and laypeople were asked to rate each photo in order of attractiveness. A total of 100 complete responses were received. Incisor-GALL distances of +4 mm (41%) and +2 mm (40%) were most commonly considered "most esthetic" for the female volunteer (P < .001). For the male volunteer, there were 2 peak "most esthetic" responses: incisor-GALL distances of 0 mm (37%) and -4 mm (32%) (P < .001). Respondents considered maxillary incisor position 2 to 4 mm anterior to GALL most attractive in a woman and 0 to 4 mm posterior to GALL most esthetic in a man. Using these modified target distances, this analysis may be useful for orthognathic surgery planning. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Inclined Fiber Pullout from a Cementitious Matrix: A Numerical Study

    Directory of Open Access Journals (Sweden)

    Hui Zhang

    2016-09-01

    Full Text Available It is well known that fibers improve the performance of cementitious composites by acting as bridging ligaments in cracks. Such bridging behavior is often studied through fiber pullout tests. The relation between the pullout force vs. slip end displacement is characteristic of the fiber-matrix interface. However, such a relation varies significantly with the fiber inclination angle. In the current work, we establish a numerical model to simulate the entire pullout process by explicitly representing the fiber, matrix and the interface for arbitrary fiber orientations. Cohesive elements endorsed with mixed-mode fracture capacities are implemented to represent the bond-slip behavior at the interface. Contact elements with Coulomb’s friction are placed at the interface to simulate frictional contact. The bond-slip behavior is first calibrated through pull-out curves for fibers aligned with the loading direction, then validated against experimental results for steel fibers oriented at 30 ∘ and 60 ∘ . Parametric studies are then performed to explore the influences of both material properties (fiber yield strength, matrix tensile strength, interfacial bond and geometric factors (fiber diameter, embedment length and inclination angle on the overall pullout behavior, in particular on the maximum pullout load. The proposed methodology provides the necessary pull-out curves for a fiber oriented at a given angle for multi-scale models to study fracture in fiber-reinforced cementitious materials. The novelty lies in its capacity to capture the entire pullout process for a fiber with an arbitrary inclination angle.

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

    Science.gov (United States)

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

    2013-05-22

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

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

    Directory of Open Access Journals (Sweden)

    Bingah Fitri Melati

    2014-06-01

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

  11. Effects of posttreatment skeletal maturity measured with the cervical vertebral maturation method on incisor alignment relapse.

    Science.gov (United States)

    Fudalej, Piotr; Rothe, Laura E; Bollen, Anne-Marie

    2008-08-01

    Our aim was to test the hypothesis that relapse of incisor alignment is associated with skeletal maturity at the end of treatment, as assessed with the cervical vertebral maturation (CVM) method. This was a case-control study with information from the postretention database at the University of Washington. Mandibular incisor irregularity (II) at least 10 years out of retention (T3) was used to define the subjects (II >6 mm, relapse group) and the controls (II 0.05). Pretreatment II and postretention time were found to be correlated with long-term incisor stability (P = 0.007 and 0.034, respectively). Sex was not related to relapse (P = 0.33). Maturity of craniofacial structures at the end of treatment evaluated with the CVM method is not associated with long-term stability of incisor alignment.

  12. A boy with a cleft lip and palate, tritubercular incisors, and finger anomaly

    NARCIS (Netherlands)

    Hennekam, R. C.; van der Horst, C. M.

    1996-01-01

    A boy is described with a unilateral cleft lip and palate, maxillary tritubercular incisors, and unilateral radial torsion of his ringfinger. Family history was uninformative. We have been unable to find a similar case in the literature

  13. Orthodontic management of excessive incisor display of an adult bilateral cleft lip and palate patient

    Directory of Open Access Journals (Sweden)

    Om Prakash Kharbanda

    2016-01-01

    Full Text Available This report entails successful orthodontic treatment of a case of postsurgical malocclusion, short upper lip, and excessive incisor display in an adult patient with bilateral cleft lip and palate. The patient underwent cleft lip repair at an early age of 2 years followed by palatoplasty at the age of 6 years and alveoloplasty at an age of 26 years. He reported with irregular teeth, inability to close lips, excessive visibility of upper incisors associated with short upper lip and difficulty in speech. He was treated with maxillary arch expansion, arch alignment, and intrusion of the incisors followed by prosthetic replacement of the missing right and left lateral incisors. Subsequently, he underwent nose and lip revision surgery at the age of 32 years. The orthodontic procedures and prosthetic rehabilitation have resulted in a near normal dental occlusion with significant improvement in esthetics and psychosocial benefits to the individual. These benefits were further enhanced by nose and lip revision surgery.

  14. Innovative biomechanics for orthodontic correction of torsiversion of maxillary central incisor caused by twin mesiodens

    Directory of Open Access Journals (Sweden)

    Nitika Monga

    2014-01-01

    Full Text Available Mesiodens is the most common type of supernumerary teeth found in the premaxilla between the two central incisors. Early and proper diagnosis and appropriate treatment plan is critical in eluding the extent of treatment needed. This case report presents the successful orthodontic and esthetic management of an unusual case of Indian origin with twin mesiodens in the maxillary arch causing torsiversion and attrition of mandibular incisors due to occlusal trauma.

  15. Innovative biomechanics for orthodontic correction of torsiversion of maxillary central incisor caused by twin mesiodens.

    Science.gov (United States)

    Monga, Nitika; Kharbanda, Om Prakash; Duggal, Ritu

    2014-04-01

    Mesiodens is the most common type of supernumerary teeth found in the premaxilla between the two central incisors. Early and proper diagnosis and appropriate treatment plan is critical in eluding the extent of treatment needed. This case report presents the successful orthodontic and esthetic management of an unusual case of Indian origin with twin mesiodens in the maxillary arch causing torsiversion and attrition of mandibular incisors due to occlusal trauma.

  16. Influence of maxillary incisor edge asymmetries on the perception of smile esthetics among orthodontists and laypersons.

    Science.gov (United States)

    Machado, Andre Wilson; Moon, Won; Gandini, Luiz Gonzaga

    2013-05-01

    Our objective was to determine the perception of smile esthetics among orthodontists and laypeople with respect to asymmetries on the maxillary incisor edges in a frontal smile analysis. Two frontal close-up smile photos of 2 women, 1 white and 1 Afro-Brazilian, were selected for this study. Both smiles displayed healthy maxillary anterior dentitions. The images were digitally altered to create tooth wear on the maxillary left central and lateral incisors in 0.5-mm increments. The final images were randomly assembled into a photo album that was given to 120 judges, 60 orthodontists and 60 laypersons. Each rater was asked to evaluate the attractiveness of the images with visual analog scales. The data collected were statistically analyzed with 1-way analysis of variance with the Tukey post-hoc test and the unpaired Student t test. The most attractive smiles in both types of smiles were those without asymmetries and the 0.5-mm wear in the lateral incisor. In general, tooth wear was considered unattractive by both groups of raters following a pattern: the more tooth wear, the more unattractive the smile; tooth wear in the central incisor was considered more unattractive than in the lateral incisor. For both group of raters, 0.5 mm of wear in the central incisor was considered unattractive, whereas the thresholds for lateral incisor discrepancies were 0.5 mm for orthodontists and 1.0 mm for laypersons. The result of this study corroborates the clinical assumption that symmetry between the maxillary central incisors is a paramount goal for esthetic treatments. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  17. Assessment of association between molar incisor hypomineralization and hypomineralized second primary molar

    OpenAIRE

    Mittal, Rakesh; Chandak, Shweta; Chandwani, Manisha; Singh, Prabhat; Pimpale, Jitesh

    2016-01-01

    Background: The term molar incisor hypomineralization (MIH) has been described as a clinical entity of systemic origin affecting the enamel of one or all first permanent molars and also the incisors; less frequently the second primary molars have also been reported to develop hypomineralization of the enamel, along with MIH. Aim: To scrutinize the association between hypomineralized second primary molars (HSPMs) and MIH and their prevalence in schoolgoing pupils in Nagpur, Maharashtra, India ...

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

    OpenAIRE

    Mishra, Apurva; Pandey, Ramesh K

    2016-01-01

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

  19. Molar Incisor Hypomineralization: A Study of Prevalence and Etiology in a Group of Iranian Children

    OpenAIRE

    Ahmadi, Rahil; Ramazani, Nahid; Nourinasab, Rahmatollah

    2012-01-01

    Objective The aim of this study was to investigate the prevalence of molar incisor hypomineralization (MIH) and its relationship with systemic conditions in a group of Iranian children. Methods The study population comprised of 433 7-9 year olds, from four schools in Zahedan, Iran. Subjects were evaluated clinically by one examiner, and at a separate session, their mothers completed a coded medical history questionnaire. Hypo-mineralized molars and incisors were recorded based on DDE (develop...

  20. Frequency and severity of molar incisor hypomineralization (mih) in a group of mexican children, 2014

    OpenAIRE

    Murrieta Pruneda, José Francisco; Torres Vargas, Jessica; Sánchez Meza, Julieta del Carmen

    2016-01-01

    The frequency of incisor molar hypomineralization is variable, which may be present in up to 25% of the population. Objective. To establish frequency and severity of MIH in a group of Mexican children. Material and Methods. A cross-sectional study was carried out in a convenience sample composed by 433 children between 8 and 12 years old, of both sexes. The survey looked at the clinical examination of the permanent first molars and incisors considering the criteria set by the European Academy...

  1. Maxillary lateral incisor agenesis and its relationship to overall tooth size.

    Science.gov (United States)

    Wright, Jane; Bosio, Jose A; Chou, Jang-Ching; Jiang, Shuying S

    2016-02-01

    Agenesis of the maxillary lateral incisor has been linked to differences in the size of the remaining teeth. Thus, the mesiodistal space required for definitive esthetic restoration in patients with missing maxillary lateral incisors may be reduced. The purpose of this study was to determine whether a tooth size discrepancy exists in orthodontic patients with agenesis of one or both maxillary lateral incisors. Forty sets of dental casts from orthodontic patients (19 men and 21 women; mean 15.9 years of age; all of European origin) were collected. All casts had agenesis of one or both maxillary lateral incisors. Teeth were measured with a digital caliper at their greatest mesiodistal width and then compared with those of a control group matched for ethnicity, age, and sex. Four-factor ANOVA with repeated measures of 2 factors was used for statistical analysis (α=.05). Orthodontic patients with agenesis of one or both maxillary lateral incisors exhibited smaller than normal tooth size compared with the control group. The maxillary arch had a larger tooth size difference between the control and test groups than the mandibular arch (there was a significant Jaw × Group interaction [F=4.78, P=.032]). Agenesis of one or both maxillary lateral incisors is significantly associated with tooth size discrepancy, which may affect the space remaining for restoration of the remaining teeth. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  2. Maxillary incisors changes during space closure with conventional and skeletal anchorage methods: a systematic review.

    Science.gov (United States)

    Jayaratne, Yasas Shri Nalaka; Uribe, Flavio; Janakiraman, Nandakumar

    2017-01-01

    The objective of this systematic review was to compare the antero-posterior, vertical and angular changes of maxillary incisors with conventional anchorage control techniques and mini-implant based space closure methods. The electronic databases Pubmed, Scopus, ISI Web of knowledge, Cochrane Library and Open Grey were searched for potentially eligible studies using a set of predetermined keywords. Full texts meeting the inclusion criteria as well as their references were manually searched. The primary outcome data (linear, angular, and vertical maxillary incisor changes) and secondary outcome data (overbite changes, soft tissue changes, biomechanical factors, root resorption and treatment duration) were extracted from the selected articles and entered into spreadsheets based on the type of anchorage used. The methodological quality of each study was assessed. Six studies met the inclusion criteria. The amount of incisor retraction was greater with buccally placed mini-implants than conventional anchorage techniques. The incisor retraction with indirect anchorage from palatal mini-implants was less when compared with buccally placed mini-implants. Incisor intrusion occurred with buccal mini-implants, whereas extrusion was seen with conventional anchorage. Limited data on the biomechanical variables or adverse effects such as root resorption were reported in these studies. More RCT's that take in to account relevant biomechanical variables and employ three-dimensional quantification of tooth movements are required to provide information on incisor changes during space closure.

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

    Directory of Open Access Journals (Sweden)

    Amarlal Deepti

    2007-01-01

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

  4. Changes of mandibular incisor in Fgfr2 S252W mutant mice

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    Xia ZHOU

    2013-11-01

    Full Text Available Objective To compare the phenotypic differences of mandibular incisor between the wild-type mice and fibroblast growth factor receptor 2 (Fgfr2 gene S252W mutant mice, and explore the influence of gain-of-function mutation in Fgfr2 gene on mandibular incisors in mice. Methods The male EⅡa-Cre mice were mated with Fgfr2S252W-neo/+ females to obtain the Fgfr2 S252W mutant mice. On the 56th day after offspring's birth (P56, samples were taken for Micro-CT, HE staining and calcein double fluorescent labeling to observe the gross appearance, tissue morphology and mineral apposition rate of mandibular incisors, respectively. Results The newborn mutant mice showed short cranial deformity, which became more obvious on P56. Micro-CT showed a significant elongation and cross-bite deformity of mandibular incisors. HE staining showed that there were more ameloblasts and odontoblasts in the mutant mice, mostly with irregular appearance; epithelial diaphragm composed of inner and outer enamel epithelium shrank. Calcein double fluorescent labeling showed that the mineral apposition rate of dentin in mutant mice was significantly higher than that in controls. Conclusion Fgfr2 S252W mutation accelerates the growth of mandibular incisors in mice, resulting in the elongation and cross-bite deformity of mandibular incisors. DOI: 10.11855/j.issn.0577-7402.2013.10.005

  5. Deepbite correction with incisor intrusion in adults: a long-term cephalometric study.

    Science.gov (United States)

    Kale Varlık, Selin; Onur Alpakan, Ödül; Türköz, Çağrı

    2013-09-01

    The purpose of this study was to investigate the long-term stability of deep overbite correction with mandibular incisor intrusion with utility arches in adult patients. Pretreatment, posttreatment, and 5-years postretention lateral cephalograms of 31 patients (mean age, 26.8 years; range, 24.1-30.9 years) with Class II Division 1 malocclusion and deepbite, treated by maxillary first premolar extraction and mandibular incisor intrusion, were traced and measured. Significant decreases in overjet and overbite (6.4 ± 1.2 and 3.9 ± 0.7 mm, respectively), significant retroclination (17° ± 1.9°) and retraction (3.8 ± 1.1 mm) of the maxillary incisors, and significant increases in protrusion (0.8 ± 1.5 mm), proclination (0.6° ± 0.9°), and intrusion (2.6 ± 1.4 mm) of the mandibular incisors were observed at posttreatment. At postretention, there were statistically significant but clinically unimportant increases in overjet and overbite (0.4 ± 0.2 and 0.8 ± 0.4 mm, respectively) and extrusion of the mandibular incisors (0.8 ± 1.1 mm). Correction of deepbite in nongrowing patients by mandibular incisor intrusion with a utility arch can be considered effective and stable. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  6. MAXILLARY INCISORS CHANGES DURING SPACE CLOSURE WITH CONVENTIONAL AND SKELETAL ANCHORAGE METHODS: A SYSTEMATIC REVIEW

    Directory of Open Access Journals (Sweden)

    Yasas Shri Nalaka JAYARATNE

    2017-12-01

    Full Text Available Purpose: The objective of this systematic review was to compare the antero-posterior, vertical and angular changes of maxillary incisors with conventional anchorage control techniques and mini-implant based space closure methods. Materials and Methods: The electronic databases Pubmed, Scopus, ISI Web of knowledge, Cochrane Library and Open Grey were searched for potentially eligible studies using a set of predetermined keywords. Full texts meeting the inclusion criteria as well as their references were manually searched. The primary outcome data (linear, angular, and vertical maxillary incisor changes and secondary outcome data (overbite changes, soft tissue changes, biomechanical factors, root resorption and treatment duration were extracted from the selected articles and entered into spreadsheets based on the type of anchorage used. The methodological quality of each study was assessed. Results: Six studies met the inclusion criteria. The amount of incisor retraction was greater with buccally placed mini-implants than conventional anchorage techniques. The incisor retraction with indirect anchorage from palatal mini-implants was less when compared with buccally placed mini-implants. Incisor intrusion occurred with buccal mini-implants, whereas extrusion was seen with conventional anchorage. Limited data on the biomechanical variables or adverse effects such as root resorption were reported in these studies. Conclusion: More RCT’s that take in to account relevant biomechanical variables and employ three-dimensional quantification of tooth movements are required to provide information on incisor changes during space closure.

  7. Bilateral symmetry of anterior maxillary incisors: evaluation of a community-based population.

    Science.gov (United States)

    Ormianer, Z; Solodukhin, A L; Lauritano, D; Segal, P; Lavi, D; Carinci, F; Block, J

    2017-01-01

    The final outcome of dental treatment needs to be not only clinically sufficient, but also esthetically pleasing. Bilateral symmetry in the maxillary incisor teeth is of significant importance in esthetic dentistry. In restorative dentistry, symmetry refers to the appearance of balance around the dental midline. The purpose of this study was to measure and compare the maxillary incisor teeth dimensions from both sides of the dental midline, in order to asses if this symmetry occurs naturally. From the student community population at Tel Aviv University, 66 students between the ages of 20-35 (35 males, 31 females) were enrolled and gave consent. The inclusion criteria for this study were: upper maxillary incisors that have never undergone restorative or rehabilitative treatment, and no history of orthodontic treatment. Standardized digital photographs were taken, and the length and width of the maxillary central and lateral incisors were measured and proportions were calculated. SPSS was used to compare the measured differences between teeth on the left versus right of the midline. Tooth proportions were not significantly different between the left and right sides. Asymmetry was found only between the lengths of the maxillary lateral incisors (p=0.009); the width for these teeth was symmetrical. A significant statistical difference was not found on most parameters when evaluating symmetry of the upper incisors. Therefore, when treating the esthetically important anterior of the mouth, care must be taken to ensure bilateral symmetry to mirror the natural symmetry found in most patients.

  8. Localization of Impacted Maxillary Canines and Root Resorption of Neighbouring Lateral Incisor Using Cone Beam Computed Tomography

    Directory of Open Access Journals (Sweden)

    Elham Farokh-Gisour

    2016-08-01

    Full Text Available Canine impaction is one of the most prevalent impactions and it affects aesthetic and function of the oral cavity. Recent advances in 3D imaging has provided new facilities for precise localization of the impacted teeth and their effect on adjacent roots. The aim of this study was to assess the location of impacted canine and adjacent root resorption by CBCT in an Iranian adolescent population. In this retrospective, descriptive-analytic study, CBCT images of 25 orthodontic patients (seven had bilateral canine impaction and the bucco-lingual and vertical position of teeth and tooth location to the adjacent teeth were evaluated using CBCT. A total of 32 impacted canines were examined (24 females,8 males. Of these, 11 (34.4% were located buccally, 11 (34.4% mid-alveolar and 10 (31.1% palatally .in vertical position, 7 of the impacted canines (21.9% were coronal and 16 (50% in the cervical 2/3 and 8 teeth (25% were positioned in cervical one third and one of them (3.1% was positioned apically. Among 32 studied teeth, 6 (%8.8 of them did not cause incisor degeneration and 8 (%25 teeth cause mild degeneration and none of them caused intense incisor resorption. The average size of follicle was 3.6mm. According to the results, CBCT is a good tool for evaluation of impacted canine location and its effect on adjacent roots. Another important finding was the high prevalence of root resorption (90%, which implies immediate treatment of impacted canines.

  9. Comparison of interpupillary distance and combined mesiodistal width of maxillary central incisor teeth in two ethnic groups of Northeast India: An in vivo study.

    Science.gov (United States)

    Barman, Jogeswar; Serin, Sangma

    2018-01-01

    Anthropometric measurements of the face can be used as a guide in selecting proper sized anterior teeth. The aim of this study is to evaluate the relationship between the interpupillary distance (IPD) and the combined mesiodistal width of maxillary central incisors (MDW of MCIs) to establish their morphometric criterion and their significance in two ethnic groups of Northeast India. A total of 120 participants consisting of 60 indigenous students each from Assam and Meghalaya in the age group of 18-25 years were selected after taking their written consent. Standardized facial frontal photographs of all the participants were taken using a digital camera in such a manner that maxillary anterior teeth were visible. The photographs were uploaded onto the computer and saved in a file. Anthropometric measurements of IPD and combined MDW of MCIs in centimeters were made using both Adobe Photoshop ® 7.0 software program and manually using a digital vernier caliper on the developed photographs to a same size of 15 cm × 10 cm. Data obtained were tabulated and analyzed using Student "t"-test and Pearson correlation test. The present study reveals a positive correlation with a high degree of statistical significance between IPD and combined mesiodistal width of maxillary central incisors among all the samples irrespective of gender and ethnicity where P < 0.01. IPD can be used as a guide in determining the suitable mesiodistal dimension of the maxillary central incisors.

  10. Prevalence of Molar Incisor Hypomineralization in Mexican Children.

    Science.gov (United States)

    Gurrusquieta, Brenda Jaime; Núñez, Victor Manuel Mendoza; López, María Lilia Adriana Juárez

    To determine the prevalence of and factors associated with molar incisor hypomineralization (MIH) in schoolchildren aged 6-12 years. This study included 1156 schoolchildren aged 6-12 years, living in Mexico City. A previously standardised examiner (k = 0.79) applied the diagnostic criteria for MIH from the European Academy of Paediatric Dentistry. Children's parents completed a questionnaire about medical conditions in the perinatal period and the first 3 years of their children's lives. Descriptive measures were examined, multivariate logistic regression analysis was performed, and odds ratios (ORs) were calculated. The subjects were 582 (50.4%) females and 574 (49.6%) males, with an average age of 8.4 ± 1.6 years. The prevalence of MIH was 15.8%, and this condition was more prevalent in children aged 9-12 years than in those aged 6-8 years (18% vs. 13.7%, p prevalence of MIH in a group of Mexican schoolchildren was 15.8%. Medical conditions in the first years of life were more prevalent in children affected by MIH.

  11. The prevalence of molar incisor hypomineralization: evidence from 70 studies.

    Science.gov (United States)

    Zhao, Dongdong; Dong, Bao; Yu, Dandan; Ren, Qiongqiong; Sun, Yehuan

    2018-03-01

    A growing number of studies have investigated the prevalence of Molar Incisor Hypomineralization (MIH) around the world. The aim of this study was to systematically estimate the pooled prevalence of MIH. A comprehensive literature research was completed in English and Chinese databases. Random effect models were used to calculate the pooled prevalence. To address the heterogeneity, meta-regression, and sensitivity analyzes were conducted. Publication bias was estimated by trim and fill method. Seventy eligible studies were included. The pooled prevalence of MIH was 14.2% globally. In subgroup analysis, South America (18.0%, 95% CI: 13.8-22.2) and Spain (21.1%, 95% CI: 17.7-24.6) had the highest prevalence. There was no significant difference between males (14.3%, 95% CI: 12.0-16.6) and females (14.4%, 95% CI: 12.8-15.9). The prevalence of MIH among children 10 years of age or younger (15.1%, 95% CI: 12.1-18.2) was much higher than the prevalence of MIH among older children (12.1%, 95% CI: 8.0-16.3). Sample size explained 15.7% heterogeneity. MIH has a high incidence globally, especially among children <10 years old. It is, therefore, imperative to develop more appropriate dental healthcare strategies to care for these children and to identify the etiology of MIH to prevent it occurring. © 2017 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Prevalence of molar incisor hypomineralization (MIH) in Singaporean children.

    Science.gov (United States)

    Ng, Jing Jing; Eu, Oy Chu; Nair, Rahul; Hong, Catherine Hsu Ling

    2015-03-01

    There is a lack of data on molar incisor hypomineralization (MIH) in Asia, but this is not an indication that MIH is rare in the Asian population. Early identification of MIH is important as affected teeth frequently display post-eruptive enamel loss which would result in rapid caries progression. This objective of this study was to assess the prevalence of MIH in Singaporean children. Patients were recruited from 30 schools across Singapore. All children were examined by a single dentist, and the judgement criteria used were based on the 2003 European Academy of Paediatric Dentistry criteria. A total of 1083 children; average age of 7.7 ± 0.3 years were examined. One hundred and thirty-five children (12.5%) had MIH. A significantly higher proportion of children of the Malay ethnicity had MIH, compared to Chinese children (P = 0.02). Post-eruptive enamel breakdown and the presence of atypical restorations were correlated with increasing number of MIH teeth/child (Rho= 0.599, P < 0.001) and the cumulative enamel opacity colour score (Rho = 0.601, P < 0.001). Our findings suggest the role of ethnicity in MIH occurrence and that MIH severity may be influenced by the number of MIH teeth/child and the cumulative enamel opacity colour score. © 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Dens invaginatus in a geminated maxillary lateral incisor.

    Science.gov (United States)

    Pallivathukal, Renjith George; Misra, Alok; Nagraj, Sumanth Kumbargere; Donald, Preethy Mary

    2015-05-22

    Dens invaginatus (DI) and gemination are two developmental abnormalities that are well reported in the dental literature, but their coexistence in a single tooth is rare. Such situations worsen the risk factors associated with these anomalies, and the treatment plan should be customised as they possess altered morphology and anatomy. A 19-year-old girl came for evaluation of a cracked tooth in the front region of the upper jaw. The tooth showed clinical features of gemination and radiographic features of DI, and was diagnosed as DI in geminated maxillary lateral incisor. The differential diagnoses based on clinical appearance without radiographic investigation may warrant the treatment approach if these two abnormalities coexist in a single tooth. The report also highlights the importance of three-dimensional imaging in diagnosis and treatment planning of teeth with altered pulp canal anatomy. There are few reported cases in the literature detailing the treatment options for these two anomalies occurring in the same tooth. 2015 BMJ Publishing Group Ltd.

  14. Aetiology of molar-incisor hypomineralization: a critical review.

    Science.gov (United States)

    Crombie, Felicity; Manton, David; Kilpatrick, Nicola

    2009-03-01

    The objective of this study was to assess the strength of evidence for the aetiology of molar-incisor hypomineralization (MIH), often as approximated by demarcated defects. A systematic search of online medical databases was conducted with assessment of titles, abstracts, and finally full articles for selection purposes. The level and quality of evidence were then assessed for each article according to Australian national guidelines. Of 1123 articles identified by the database search, 53 were selected for review. These covered a variety of potential aetiological factors, some of which were grouped together for convenience. The level of evidence provided by the majority of papers was low and most did not specifically investigate MIH. There was moderate evidence that polychlorinated biphenyl/dioxin exposure is involved in the aetiology of MIH; weak evidence for the role of nutrition, birth and neonatal factors, and acute or chronic childhood illness/treatment; and very weak evidence to implicate fluoride or breastfeeding. There is currently insufficient evidence in the literature to establish aetiological factor/s relevant for MIH. Improvements in study design, as well as standardization of diagnostic and examination protocols, would improve the level and strength of evidence.

  15. Dental caries experience and Molar-Incisor Hypomineralization.

    Science.gov (United States)

    Jeremias, Fabiano; de Souza, Juliana Feltrin; Silva, Cristiane Maria da Costa; Cordeiro, Rita de Cássia Loiola; Zuanon, Angela Cristina Cilense; Santos-Pinto, Lourdes

    2013-01-01

    This cross-sectional study assessed the prevalence and severity of the enamel defects, known as Molar-Incisor Hypomineralization (MIH) and its relationship to dental caries. A sample of 1157 schoolchildren (population based), aged 6-12 years, of the Araraquara city-Brazil, was evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria by two trained examiners. The dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Data were analyzed using ANOVA and Chi-square tests (p < 0.05). The socioeconomic status was collected using a questionnaire answered by parents. The prevalence of MIH was 12.3%. Mild impairment was the most frequent diagnosis. DMFT of children with MIH was 0.89 (± 1.18), which are higher than those of the unaffected group (0.43 ± 1.01). An association was found between dental caries only in the permanent dentition of children with MIH (p = 0.0001). Family income was considered low in 85% of the families of children with MIH in the public system, while in private school it was 18% (p < 0.05). The prevalence of MIH in Araraquara was associated with greater caries experience in the permanent dentition.

  16. Molar incisor hypomineralization in HIV-infected children and adolescents.

    Science.gov (United States)

    Andrade, Natália Silva; Pontes, Alessandra Silva; de Sousa Paz, Hélvis Enri; de Moura, Marcoeli Silva; Moura, Lúcia de Fátima Almeida de Deus; Lima, Marina de Deus Mourade

    2017-01-01

    The objective was to determine the prevalence of molar incisor hypomineralization (MIH) among individuals between 7 and 15 years old infected or noninfected with human immunodeficiency virus (HIV). The study was conducted with 33 HIV-infected individuals (study group; SG) and 66 non-HIV-infected schoolchildren (control group; CG), paired by gender and age. Data collection was based on medical records (SG), a questionnaire for caregivers and oral examination for diagnosis of MIH (European Academy of Pediatric Dentistry criteria) and caries (DMFT index and ICDAS). Data were analyzed with Mann-Whitney, chi-square, and Fisher's exact tests and logistic regression. In SG, MIH (45.5%) and caries (87.9%) had higher prevalence. MIH was associated with use of protease inhibitors in SG (OR: 2.14; 95% CI: 1.21 to 3.77) and incubator need in CG (OR: 2.80; 95% CI: 1.71 to 9.10). HIV-infected patients had a higher prevalence of MIH and dental caries in the permanent dentition. © 2016 Special Care Dentistry Association and Wiley Periodicals, Inc.

  17. Sex Differences in Incline-Walking among Humans.

    Science.gov (United States)

    Wall-Scheffler, Cara M

    2015-12-01

    Previous research has shown that people tend to walk around the speed that minimizes energy consumption when traveling a given distance. It has further been shown that men and women have different speeds that minimize energy and that women will choose slower speeds when the activity itself is a high-rate activity (e.g. carrying a load). Here we investigate what men and women will do when given a high rate walking activity, namely walking on an inclined surface. Fourteen people (nine men and five women) walked at four speeds on a level treadmill and four speeds on an inclined treadmill while their metabolic rate, kinematics and core temperature were monitored. Following the data collection, participants were asked to identify their ‘preferred’ walking speed at each of the conditions. Cost of transport (CoT) curves were calculated for each individual, and the delta between the preferred and the ‘optimal’ speeds were calculated. People chose to walk at slightly slower speeds on the level; there was minimal change in the cost to walk at these slower speeds. Women walked at absolutely slower speeds on the incline than men (P=0.06) and had significantly larger speed deltas (P=0.02), thus choosing to walk at slower rate speeds. Women also showed a significant relationship between the rate of activity and core temperature, whereas men did not. This is consistent with other research showing that women choose behavioral strategies to minimize body temperature changes. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  18. Flame spread over inclined electrical wires with AC electric fields

    KAUST Repository

    Lim, Seung J.

    2017-07-21

    Flame spread over polyethylene-insulated electrical wires was studied experimentally with applied alternating current (AC) by varying the inclination angle (θ), applied voltage (VAC), and frequency (fAC). For the baseline case with no electric field applied, the flame spread rate and the flame width of downwardly spreading flames (DSFs) decreased from the horizontal case for −20° ≤ θ < 0° and maintained near constant values for −90° ≤ θ < −20°, while the flame spread rate increased appreciably as the inclination angle of upwardly spreading flames (USFs) increased. When an AC electric field was applied, the behavior of flame spread rate in DSFs (USFs) could be classified into two (three) sub-regimes characterized by various functional dependences on VAC, fAC, and θ. In nearly all cases of DSFs, a globular molten polyethylene formed ahead of the spreading flame edge, occasionally dripping onto the ground. In these cases, an effective flame spread rate was defined to represent the burning rate by measuring the mass loss due to dripping. This effective spread rate was independent of AC frequency, while it decreased linearly with voltage and was independent of the inclination angle. In DSFs, when excessively high voltage and frequency were applied, the dripping led to flame extinction during propagation and the extinction frequency correlated well with applied voltage. In USFs, when high voltage and frequency were applied, multiple globular molten PEs formed at several locations, leading to ejections of multiple small flame segments from the main flame, thereby reducing the flame spread rate, which could be attributed to the electrospray phenomenon.

  19. Articulator-related registration and analysis of sagittal condylar inclination

    OpenAIRE

    Čimić, Samir; Kraljević Šimunković, Sonja; Simonić Kocijan, Sunčana; Matijević, Jurica; Dulčić, Nikša; Ćatić, Amir

    2015-01-01

    The purpose of this investigation was to study sagittal condylar inclination values within a uniform sample (Angle class I occlusion) using ‘articulator-related registration’ and Camper’s plane as a reference plane. The study was performed on a sample of 58 Angle class I subjects (mean age 25.1, SD 3.1). Measurements were performed with an ultrasonic jaw tracking device with six degrees of freedom. After a paraocclusal tray was fixed in the mouth, each subject had to make three protrusive ...

  20. Mining adjacent inclined coal seams of varying thickness

    Energy Technology Data Exchange (ETDEWEB)

    Batmanov, Yu.K.; Bakhtin, A.F.; Bulavka, E.I.

    1980-01-01

    In the Donbass coal basin a large number of thin coal seams located near other thicker coal seams are left. It is suggested that coal output from the Donbass could be increased by 100% and cost of mining could be lowered by 0.4-1.1 roubles per 1 ton of coal if thinner coal seams were also mined. Mining methods in the Donbass are analyzed from the point of view of reducing the cost of mining and increasing coal production. Recommendations on methods of mining thin inclined coal seams are given. (6 refs.) (In Russian)

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Finite element analysis of inclined nozzle-plate junctions

    International Nuclear Information System (INIS)

    Dixit, K.B.; Seth, V.K.; Krishnan, A.; Ramamurthy, T.S.; Dattaguru, B.; Rao, A.K.

    1979-01-01

    Estimation of stress concentration at nozzle to plate or shell junctions is a significant problem in the stress analysis of nuclear reactors. The topic is a subject matter of extensive investigations and earlier considerable success has been reported on analysis for the cases when the nozzle is perpendicular to the plate or is radial to the shell. Analytical methods for the estimation of stress concentrations for the practical situations when the intersecting nozzle is inclined to the plate or is non-radial to the shell is rather scanty. Specific complications arise in dealing with the junction region when the nozzle with circular cross-section meets the non-circular cut-out on the plate or shell. In this paper a finite element analysis is developed for inclined nozzles and results are presented for nozzle-plate junctions. A method of analysis is developed with a view to achieving simultaneously accuracy of results and simplicity in the choice of elements and their connectivity. The circular nozzle is treated by axisymmetric conical shell elements. The nozzle portion in the region around the junction and the flat plate is dealt with by triangular flat shell elements. Special transition elements are developed for joining the flat shell elements with the axisymmetric elements under non-axisymmetric loading. A substructure method of analysis is adopted which achieves considerable economy in handling the structure and also conveniently combines the different types of elements in the structure. (orig.)

  3. An Experimental Investigation on Inclined Negatively Buoyant Jets

    Directory of Open Access Journals (Sweden)

    Raed Bashitialshaaer

    2012-09-01

    Full Text Available An experimental study was performed to investigate the behavior of inclined negatively buoyant jets. Such jets arise when brine is discharged from desalination plants. A turbulent jet with a specific salinity was discharged through a circular nozzle at an angle to the horizontal into a tank with fresh water and the spatial evolution of the jet was recorded. Four different initial jet parameters were changed, namely the nozzle diameter, the initial jet inclination, the jet density and the flow rate. Five geometric quantities describing the jet trajectory that are useful in the design of brine discharge systems were determined. Dimensional analysis demonstrated that the geometric jet quantities studied, if normalized with the jet exit diameter, could be related to the densimetric Froude number. Analysis of the collected data showed that this was the case for a Froude number less than 100, whereas for larger values of the Froude number the scatter in the data increased significantly. As has been observed in some previous investigations, the slope of the best-fit straight line through the data points was a function of the initial jet angle (θ, where the slope increased with θ for the maximum levels (Ym studied, but had a more complex behavior for horizontal distances.

  4. Geosynchronous inclined orbits for high-latitude communications

    Science.gov (United States)

    Fantino, E.; Flores, R. M.; Di Carlo, M.; Di Salvo, A.; Cabot, E.

    2017-11-01

    We present and discuss a solution to the growing demand for satellite telecommunication coverage in the high-latitude geographical regions (beyond 55°N), where the signal from geostationary satellites is limited or unavailable. We focus on the dynamical issues associated to the design, the coverage, the maintenance and the disposal of a set of orbits selected for the purpose. Specifically, we identify a group of highly inclined, moderately eccentric geosynchronous orbits derived from the Tundra orbit (geosynchronous, eccentric and critically inclined). Continuous coverage can be guaranteed by a constellation of three satellites in equally spaced planes and suitably phased. By means of a high-precision model of the terrestrial gravity field and the relevant environmental perturbations, we study the evolution of these orbits. The effects of the different perturbations on the ground track (which is more important for coverage than the orbital elements themselves) are isolated and analyzed. The physical model and the numerical setup are optimized with respect to computing time and accuracy. We show that, in order to maintain the ground track unchanged, the key parameters are the orbital period and the argument of perigee. Furthermore, corrections to the right ascension of the ascending node are needed in order to preserve the relative orientation of the orbital planes. A station-keeping strategy that minimizes propellant consumption is then devised, and comparisons are made between the cost of a solution based on impulsive maneuvers and one with continuous thrust. Finally, the issue of end-of-life disposal is discussed.

  5. Dissipative descent: rocking and rolling down an incline

    Science.gov (United States)

    Balmforth, N. J.; Bush, J. W. M.; Vener, D.; Young, W. R.

    We consider the dynamics of a hollow cylindrical shell that is filled with viscous fluid and another, nested solid cylinder, and allowed to roll down an inclined plane. A mathematical model is compared to simple experiments. Two types of behaviour are observed experimentally: on steeper slopes, the device accelerates; on shallower inclines, the cylinders rock and roll unsteadily downhill, with a speed that is constant on average. The theory also predicts runaway and unsteady rolling motions. For the rolling solutions, however, the inner cylinder cannot be suspended in the fluid by the motion of the outer cylinder, and instead falls inexorably toward the outer cylinder. Whilst only occurs after an infinite time, the system slows progressively as the gap between the cylinders narrows, owing to heightened viscous dissipation. Such a deceleration is not observed in the experiments, suggesting that some mechanism limits the approach to contact. Coating the surface of the inner cylinder with sandpaper of different grades changes the rolling speed, consistent with the notion that surface roughness is responsible for limiting the acceleration.

  6. Breakdown of air pockets in downwardly inclined sewerage pressure mains.

    Science.gov (United States)

    Lubbers, C L; Clemens, F H L R

    2006-01-01

    In the Netherlands, wastewater is collected in municipal areas and transported to centralised WWTPs by an extensive system of pressure mains. Over the last decades these pressure mains did not receive much attention in terms of monitoring of performance or maintenance. A recent inventory showed that half of the pressure mains show an increased pressure loss for no directly obvious reason. One of the many causes that account for the reduction of the flow capacity is the occurrence of free gas in the pipeline. During dry weather periods with low flow velocities, gas may accumulate at high points in the system. Once the velocity increases during storm weather flow, the air pockets may be broken down and transported to the end of the system. A research study is started focussing on the description of the gas-water phenomena in wastewater pressure mains with respect to transportation of gas. An experimental facility is constructed for the study of multi-phase flow. This paper describes the preliminary results of experiments on breakdown rates of gas pockets as a function of inclination angle and water flow rate. The results show an increasing breakdown rate with increasing inclination angle.

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

    OpenAIRE

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

    2015-01-01

    An 18-year-old female patient visited a university orthodontics department with a chief complaint of an unesthetic appearance of her teeth, including a protruded upper central incisor and unsatisfactory results from previous orthodontic treatment. Pretreatment records showed a Class II skeletal and dental relation with proclined upper and lower incisors, replacement of an absent upper left central incisor with the left upper cuspid, presence of the upper left deciduous cuspid, mild crowding, ...

  8. Determinants of permanent first incisor eruption in grazing Australian Angora goats.

    Science.gov (United States)

    McGregor, B A; Butler, K L

    2011-12-01

    To investigate the effects of live weight, sex and other factors on deciduous (first incisor) loss and permanent first incisor development in Angora goats. Goats were part of a pen study on the effects of energy intake in Angora does during pregnancy and lactation on kid growth and development. The design was three levels of nutrition in mid-pregnancy × two levels of postnatal nutrition in 17 randomised blocks. Conception times were calculated by using artificial insemination, with ultrasound examination 43 days after insemination. Does were fed different amounts of a formulated diet in their pens. After weaning, goats were grazed in sex groups. Deciduous first incisor loss and permanent first incisor development were recorded at 11 time points from 14 to 20 months of age. For each sex, the time for visible eruption and full development of permanent first incisor declined linearly with increased live weight by 5.9 and 5.4 days/kg live weight, respectively. The time to reach similar development stages for first permanent incisors eruption was 3 months longer for the lightest animals compared with the heaviest animals. Date of birth, birth weight, doe age, growth rates, mid-pregnancy and postnatal nutrition, parity, day of weaning and weaning weight had no detectable effect. The results explain much of the substantial range in reported first permanent incisor eruption dates for small ruminants and have application in ageing of goats, marketing of kids for meat, in the selection of animals for breeding flocks and in educational material. © 2011 The Authors. Australian Veterinary Journal © 2011 Australian Veterinary Association.

  9. Etiology of molar incisor hypomineralization - A systematic review.

    Science.gov (United States)

    Silva, Mihiri J; Scurrah, Katrina J; Craig, Jeffrey M; Manton, David J; Kilpatrick, Nicky

    2016-08-01

    Molar incisor hypomineralization (MIH) is a common developmental dental defect of permanent teeth, which can increase the risk of dental caries, infection and hospitalization. The etiology is currently unclear although prenatal or early childhood health factors are suspected. The aim of this systematic review was to assess the strength of evidence linking etiological factors with MIH. A systematic search was conducted using the Medline and Embase electronic databases for studies investigating environmental etiological factors of MIH. Two reviewers assessed the eligibility of studies. The level of evidence and bias was determined for all eligible studies according to Australian National Health and Medical Research Council guidelines for systematic reviews of etiology and the Newcastle-Ottawa Scale. From a total of 2254 studies identified through electronic and hand searching, 28 were eligible for inclusion. Twenty-five of these investigated MIH and three investigated a related condition in primary teeth, hypomineralized second primary molars (HSPM), and these were analysed separately. A limited number of studies reported significant associations between MIH and pre- and perinatal factors such as maternal illness and medication use in pregnancy, prematurity and birth complications. Early childhood illness was implicated as an etiological factor in MIH in several studies, in particular fever, asthma and pneumonia. The studies investigating HSPM revealed an association with maternal alcohol consumption, infantile fever and ethnicity. However, the validity of these findings is impaired by study design, lack of adjustment for confounders, lack of detail and consistency of exposures investigated and poor reporting. Childhood illness is likely to be associated with MIH. Further prospective studies of the etiology of MIH/HSPM are needed. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Conservative approach for the management of congenital bilateral agenesis of permanent mandibular incisors: case report and literature review.

    Science.gov (United States)

    Zarow, M; D'Arcangelo, C; D'Amario, M; Marzo, G

    2015-06-01

    Agenesis of mandibular incisors can lead to compromised dental and facial aesthetics and therefore requires appropriate treatment. When retained primary incisors are associated to this condition, a medium-term restoration may be provided before any definitive treatment to provide aesthetic relief to the young patient. The aim of this paper is to discuss the aesthetic management of a case with bilateral congenital agenesis of permanent incisors and retained primary incisors, which were successfully treated with direct composite restorations. This appears a viable technique that restores function and aesthetics with a very conservative approach.

  11. Approaching the brachistochrone using inclined planes—striving for shortest or equal travelling times

    Science.gov (United States)

    Theilmann, Florian

    2017-01-01

    The classical brachistochrone problem asks for the path on which a mobile point M just driven by its own gravity will travel in the shortest possible time between two given points A and B. The resulting curve, the cycloid, will also be the tautochrone curve, i.e. the travelling time of the mobile point will not depend on its starting position. We discuss three similar problems of increasing complexity that restrict the motion to inclined planes. Without using calculus we derive the respective optimal geometry and compare the theoretical values to measured travelling times. The observed discrepancies are quantitatively modelled by including angular motion and friction. We also investigate the correspondence between the original problem and our setups. The topic provides a conceptually simple yet non-trivial problem setting inviting for problem based learning and complex learning activities such as planing suitable experiments or modelling the relevant kinematics.

  12. Experimental investigation of thermal conductivity coefficient and heat exchange between fluidized bed and inclined exchange surface

    Directory of Open Access Journals (Sweden)

    B. Stojanovic

    2009-06-01

    Full Text Available The paper presents experimental research of thermal conductivity coefficients of the siliceous sand bed fluidized by air and an experimental investigation of the particle size influence on the heat transfer coefficient between fluidized bed and inclined exchange surfaces. The measurements were performed for the specific fluidization velocity and sand particle diameters d p=0.3, 0.5, 0.9 mm. The industrial use of fluidized beds has been increasing rapidly in the past 20 years owing to their useful characteristics. One of the outstanding characteristics of a fluidized bed is that it tends to maintain a uniform temperature even with nonuniform heat release. On the basis of experimental research, the influence of the process's operational parameters on the obtained values of the bed's thermal conductivity has been analyzed. The results show direct dependence of thermal conductivity on the intensity of mixing, the degree of fluidization, and the size of particles. In the axial direction, the coefficients that have been treated have values a whole order higher than in the radial direction. Comparison of experimental research results with experimental results of other authors shows good agreement and the same tendency of thermal conductivity change. It is well known in the literature that the value of the heat transfer coefficient is the highest in the horizontal and the smallest in the vertical position of the heat exchange surface. Variation of heat transfer, depending on inclination angle is not examined in detail. The difference between the values of the relative heat transfer coefficient between vertical and horizontal heater position for all particle sizes reduces by approximately 15% with the increase of fluidization rate.

  13. Improvement in greenhouse solar drying using inclined north wall reflection

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, V.P. [Department of Mechanical Engineering, Punjab Agricultural University, Ludhiana 141004, Punjab (India); Arora, Sadhna [Department of Processing and Food Engineering, Punjab Agricultural University, Ludhiana 141004, Punjab (India)

    2009-09-15

    A conventional greenhouse solar dryer of 6 m{sup 2} x 4 m{sup 2} floor area (east-west orientation) was improved for faster drying using inclined north wall reflection (INWR) under natural as well as forced convection mode. To increase the solar radiation availability onto the product (to be dried) during extreme summer months, a temporary inclined wall covered with aluminized reflector sheet (of 50 {mu}m thickness and reflectance 0.93) was raised inside the greenhouse just in front of the vertical transparent north wall. By doing so, product fully received the reflected beam radiation (which otherwise leaves through the north wall) in addition to the direct total solar radiation available on the horizontal surface during different hours of drying. The increment in total solar radiation input enhanced the drying rate of the product by increasing the inside air and crop temperature of the dryer. Inclination angle of the reflective north wall with vertical ({beta}) was optimized for various selective widths of the tray W (1.5, 2, 2.5 and 3 m) and for different realistic heights of existing vertical north wall (h) at 25 N, 30 N and 35 N latitudes (hot climatic zones). Experimental performance of the improved dryer was tested during the month of May 2008 at Ludhiana (30.56 N) climatic conditions, India by drying bitter gourd (Momordica charantia Linn) slices. Results showed that by using INWR under natural convection mode of drying, greenhouse air and crop temperature increased by 1-6.7 C and 1-4 C, respectively, during different drying hours as compared to, when INWR was not used and saved 13.13% of the total drying time. By using INWR under forced convection mode of drying, greenhouse air and crop temperature increased by 1-4.5 C and 1-3 C, respectively, during different drying hours as compared to, when INWR was not used and saved 16.67% of the total drying time. (author)

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

    Science.gov (United States)

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

    2013-07-01

    To assess the prevalence of lateral incisor agenesis impacted canines and supernumerary teeth in a young adult male population. The panoramic radiographs of 1745 military students (mean age: 18.6 ± 0.52 years) who attended the Center of Aviation Medicine of the Armed Forces of Greece during the period 1997-2011 were initially analyzed for lateral incisor agenesis by two observers. After exclusion of the known orthodontic cases, a subgroup of 1636 examinees (mean age: 18.6 ± 0.44 years) was evaluated for canine impaction and supernumerary teeth. Twenty-eight missing lateral incisors were observed in 22 military students, indicating an incidence of 1.3% in the investigated population. No lateral incisor agenesis was detected in the mandibular arch. A prevalence rate of 0.8% was determined for canine impaction in the sample of young adults. The majority of impacted teeth (86.7%) were diagnosed in the maxillary arch. Thirty-five supernumerary teeth were observed in 24 examinees (prevalence rate: 1.5%). The ratio of supernumerary teeth located in the maxilla versus the mandible was 2.2:1. The most common type of supernumerary tooth was the upper distomolar. The prevalence of lateral incisor agenesis, canine impaction, and supernumerary teeth ranged from 0.8 to 1.5% in the sample of male Greek military students.

  15. Molar incisor hypomineralization: proportion and severity in primary public school children in Graz, Austria.

    Science.gov (United States)

    Buchgraber, Barbara; Kqiku, Lumnije; Ebeleseder, Kurt A

    2018-03-01

    The aim of this study was to determine the proportion and severity of molar incisor hypomineralization (MIH) in primary school children in Graz (southeast of Austria). In 1111 children aged 6 to 12 years (mean age 9.0 ± 1.2), a wet examination of all teeth was performed by three trained examiners using a dental chair, optimal illumination, a dental mirror, and a dental explorer. All teeth with MIH lesions were registered so that different definitions of MIH were applicable. According to the European Academy of Pediatric Dentistry criteria that were considered valid at the time of the investigation, MIH was diagnosed when at least one first primary molar (FPM) was affected. MIH was present in 78 children (7.0%). In 64 children (5.8%), at least one molar and one incisor were affected (so-called M + IH). Additionally, in 9 children, only incisors were affected. In 7 affected children, teeth other than FPMs and incisors had MIH lesions. Almost an equal number of males (38) and females (40) were affected. The upper and lower molars were equally affected. The upper incisors were more frequently affected than the lower ones. Demarcated enamel opacities were the predominant types of defects. The proportion of MIH was 7.0% in Graz, which is similar to other comparable trials. This study has proven that MIH is an existing dental problem in Graz.

  16. Strength Calculation of Inclined Sections of Reinforced Concrete Elements under Transverse Bending

    Science.gov (United States)

    Filatov, V. B.

    2017-11-01

    The authors propose a design model to determine the strength of inclined sections of bent reinforced concrete elements without shear reinforcement for the action of transverse force taking into account the aggregate interlock forces in the inclined crack. The calculated dependences to find out the components of forces acting in an inclined section are presented. The calculated dependences are obtained from the consideration of equilibrium conditions of the block over the inclined crack. A comparative analysis of the experimental values of the failure loads of the inclined section and the theoretical values obtained for the proposed dependencies and normative calculation methods is performed. It is shown that the proposed design model makes it possible to take into account the effect the longitudinal reinforcement percentage has on the inclined section strength, the element cross section height without the introduction of empirical coefficients which contributes to an increase in the structural safety of design solutions including the safety of high-strength concrete elements.

  17. Sensing and Positioning on Inclines and Deep Environments with Retrieval (SPIDER), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — To enable future robotic exploration systems to have greater mobility, sensing, sampling, and communication capabilities on difficult terrain such as craters,...

  18. The effect of crank position and backrest inclination on shoulder load and mechanical efficiency during handcycling

    NARCIS (Netherlands)

    Arnet, U.; van Drongelen, S.; Schlussel, M.; Lay, V.; van der Woude, L.H.V.; Veeger, H.E.J.

    2014-01-01

    Handbikes come in different models and setups, but only limited knowledge is available on the handbike-user interface. The aim of this study was to identify optimal handbike setups, assuming that in such a setup mechanical efficiency is high, while shoulder load is low. Thirteen subjects with a

  19. The effect of crank position and backrest inclination on shoulder load and mechanical efficiency during handcycling

    NARCIS (Netherlands)

    Arnet, U.; van Drongelen, S.; Schluessel, M.; Lay, V.; van der Woude, L. H. V.; Veeger, H. E. J.

    Handbikes come in different models and setups, but only limited knowledge is available on the handbike-user interface. The aim of this study was to identify optimal handbike setups, assuming that in such a setup mechanical efficiency is high, while shoulder load is low. Thirteen subjects with a

  20. Unique operations for a highly inclined, elliptical, geosynchronous satellite

    Science.gov (United States)

    Anglin, Patrick T.; Briskman, Robert D.

    2004-08-01

    The first space segment devoted to a Digital Audio Radio Service (DARS) for the Continental United States (CONUS) was established when the last satellite of a three satellite constellation (Flight Models FM-1, FM-2 and FM-3) was launched in November 2000. Each satellite is in a highly inclined, elliptical, geosynchronous orbit that is separated by 120° in Right Angle of the Ascending Node (RAAN) from the other two satellites' orbits. This results in an 8 h phasing in ground track between each satellite. These distinct orbits provide superior look angles and signal availability to mobile receivers in the northern third of the United States when compared to geostationary satellites. However, this unique orbital constellation results in some particular performance and operational differences from geostationary orbit satellites. Some of these are: Earth Sensor noise, maneuver implementation and power management. Descriptions and performance improvements of these orbit specific operations are detailed herein.

  1. Friction and drag forces on spheres propagating down inclined planes

    Science.gov (United States)

    Tee, Yi Hui; Longmire, Ellen

    2017-11-01

    When a submerged sphere propagates along an inclined wall at terminal velocity, it experiences gravity, drag, lift, and friction forces. In the related equations of motion, the drag, lift and friction coefficients are unknown. Experiments are conducted to determine the friction and drag coefficients of the sphere over a range of Reynolds numbers. Through high speed imaging, translational and rotational velocities of spheres propagating along a glass plate are determined in liquids with several viscosities. The onset of sliding motion is identified by computing the dimensionless rotation rate of the sphere. Using drag and lift coefficients for Re friction coefficients are calculated for several materials. The friction coefficients are then employed to estimate the drag coefficient for 350 frictional force over this Re range. Supported by NSF (CBET-1510154).

  2. Simulation of Solar Radiation Incident on Horizontal and Inclined Surfaces

    Directory of Open Access Journals (Sweden)

    MA Basunia

    2012-12-01

    Full Text Available A computer model was developed to simulate the hourly, daily and monthly average of daily solar radiation on horizontal and inclined surfaces. The measured hourly and daily solar radiation was compared with simulated radiation, and favourable agreement was observed for the measured and predicted values on clear days. The measured and simulated monthly averages of total (diffuse and beam daily solar radiation were compared and a reasonable agreement was observed for a number of stations in Japan. The simulation showed that during the rice harvesting season, September to October, there is a daily average of 14.7 MJ/m2 of solar irradiation on a horizontal surface in Matsuyama, Japan. There is a similar amount of solar radiation on a horizontal surface during the major rice harvesting season, November to December, in Bangladesh. This radiation can be effectively utilized for drying rough rice and other farm crops.

  3. Inclined nanoimprinting lithography-based 3D nanofabrication

    Science.gov (United States)

    Liu, Zhan; Bucknall, David G.; Allen, Mark G.

    2011-06-01

    We report a 'top-down' 3D nanofabrication approach combining non-conventional inclined nanoimprint lithography (INIL) with reactive ion etching (RIE), contact molding and 3D metal nanotransfer printing (nTP). This integration of processes enables the production and conformal transfer of 3D polymer nanostructures of varying heights to a variety of other materials including a silicon-based substrate, a silicone stamp and a metal gold (Au) thin film. The process demonstrates the potential of reduced fabrication cost and complexity compared to existing methods. Various 3D nanostructures in technologically useful materials have been fabricated, including symmetric and asymmetric nanolines, nanocircles and nanosquares. Such 3D nanostructures have potential applications such as angle-resolved photonic crystals, plasmonic crystals and biomimicking anisotropic surfaces. This integrated INIL-based strategy shows great promise for 3D nanofabrication in the fields of photonics, plasmonics and surface tribology.

  4. Segregation in inclined flows of binary mixtures of spheres

    Directory of Open Access Journals (Sweden)

    Larcher Michele

    2017-01-01

    Full Text Available We outline the equations that govern the evolution of segregation of a binary mixture of spheres in flows down inclines. These equations result from the mass and momentum balances of a kinetic theory for dense flows of inelastic spheres that interact through collisions. The theory employed for segregation is appropriate for particles with relatively small differences in size and mass. The flow of the mixture is assumed to reach a fully developed state much more rapidly than does the concentrations of the two species. We illustrate the predictions of the theory for a mixture of spheres of the same diameter but different masses and for spheres of different diameters but nearly the same mass. We show the evolution of the profiles of the concentration fractions of the two types of spheres and the profiles in the final, steady state. The latter compare favourably with those obtained in discrete-element numerical simulations.

  5. Method and apparatus for logging inclined earth boreholes

    International Nuclear Information System (INIS)

    Youmans, A.H.

    1981-01-01

    An improved technique is provided for comparing the velocity of an elongated well logging instrument traversing an inclined earth borehole with the playout velocity of the well logging cable at the earth's surface to control both the cable hoist drum rotation and the rate of movement of the subsurface instrument and thus insure cable playout is in equilibrium with the logging instrument movement. Method and apparatus are described for detecting any reduction in movement of the logging instrument through the borehole and for reducing the velocity of the logging cable playout in response thereto by reducing drum rotation. Further, when the velocity of cable playout slows to a preselected value, a monitoring circuit generates control signals which actuate a means of power attached to or integral with the logging instrument which, upon initiation, apply a force to move the logging instrument upward or downward within the borehole

  6. Deformation Analysis of Fixed Bearing Inclined Plane Thrust Bearing

    Directory of Open Access Journals (Sweden)

    LI Yong--hai

    2017-02-01

    Full Text Available According to the theory of lubrication,Numerical simulation of the deformation of the thrust bearing of the fixed inclined plane was carried out,by finite element numerical analysis method and using the ANSYS software. The mathematical model of the oil film shape control equations about of the deformation and bearing is established. Analytical result showed that the force caused the tile surface generating concave deformation,and convex deformation increased with the height and the size of the load and bearing;Tile surface temperature generated convex deformation and increased with the height and the size of the temperature of bearing bush;The actual deformation of the tile surface is the superposition of the force and the thermal deformation. This conclusion can provide reference for the design and the application of thrust bearing,to reduce the tile surface,which is not conducive to the carrying capacity of the concave deformation.

  7. Transient flow and heat transfer phenomena in inclined wavy films

    Energy Technology Data Exchange (ETDEWEB)

    Serifi, Katerina; Bontozoglou, Vasilis [Department of Mechanical and Industrial Engineering, University of Thessaly, 38334, Volos (Greece); Malamataris, Nikolaos A. [Department of Mechanical Engineering, Technological Educational Institution of Western Macedonia, 50100, Kila Kozani (Greece)

    2004-08-01

    A finite-element numerical scheme is used to study rigorously the flow of an inclined liquid film and the heat transfer from the constant-temperature wall. Regular inlet disturbances are predicted to evolve into periodic or solitary waves depending on the frequency of the forcing. At very low disturbance frequencies parasitic crests appear and the regularity of the wave-train is lost. The effect of a solitary wave-train on heat transfer from the wall is studied, and it is predicted that a stationary temperature distribution develops with periodic flux variation that follows the waves. The thinning of the substrate between successive humps combines with the effect of convection at the crest and tail of the solitary humps to produce heat transfer enhancement significantly above the conduction limit. (authors)

  8. Inclined transpression in the Neka Valley, eastern Alborz, Iran

    Science.gov (United States)

    Nabavi, Seyed Tohid; Díaz-Azpiroz, Manuel; Talbot, Christopher J.

    2017-07-01

    Three major nappes in the Neka Valley in the eastern Alborz Mountains of Iran allow the Cimmerian to present convergence following the oblique collision between Iran and the southern margin of Eurasia. This work reports the identification of an inclined transpression zone recognized by field investigations and strain analyses of the geometries of formations and detailed mesoscopic structural analyses of multiple faults, folds and a cleavage. The main structures encountered include refolded recumbent asymmetric fold nappes, highly curved fold hinges, in a transpression zone that dips 37° to the NW between boundaries thrusts striking from N050° to N060°. The β angle (the angle between the zone boundary and direction of horizontal far-field shortening) is about 80°. The north-west and south-east boundaries of this zone coincide with the Haji-abad thrust and the Shah-Kuh thrust, respectively. Fold axes generally trend NE-SW and step to both right and left as a result of strike-slip components of fault displacements. Strain analyses using Fry's method on macroscopic ooids and fusulina deformed into oblate ellipsoids indicate that the natural strain varies between 2.1 and 3.14. The estimated angle between the maximum instantaneous strain axis (ISAmax) and the transpression zone boundary ( θ') is between 6° and 20°. The estimated oblique convergence angle ( α), therefore, ranges between 31° and 43°. The average kinematic vorticity number ( W k ) is 0.6, in a zone of sinistral pure shear-dominated inclined triclinic transpression. These results support the applicability of kinematic models of triclinic transpression to natural brittle-ductile shear zones.

  9. Sexual dimorphism and regional variation in human frontal bone inclination measured via digital 3D models.

    Science.gov (United States)

    Petaros, Anja; Garvin, Heather M; Sholts, Sabrina B; Schlager, Stefan; Wärmländer, Sebastian K T S

    2017-11-01

    The frontal bone is one of the most sexually dimorphic elements of the human skull, due to features such as the glabella, frontal eminences, and frontal inclination. While glabella is frequently evaluated in procedures to estimate sex in unknown human skeletal remains, frontal inclination has received less attention. In this study we present a straightforward, quick, and reproducible method for measuring frontal inclination angles from glabella and supraglabella. Using a sample of 413 human crania from four different populations (U.S. Whites, U.S. Blacks, Portuguese, and Chinese), we test the usefulness of the inclination angles for sex estimation and compare their performance to traditional methods of frontal inclination assessment. Accuracy rates in the range 75-81% were achieved for the U.S. White, U.S. Black, and Portuguese groups. For Chinese the overall accuracy was lower, i.e. 66%. Although some regional variation was observed, a cut-off value of 78.2° for glabellar inclination angles separates female and male crania from all studied populations with good accuracy. As inclination angles measured from glabella captures two sexually dimorphic features (i.e. glabellar prominence and frontal inclination) in a single measure, the observed clear male/female difference is not unexpected. Being continuous variables, inclination angles are suitable for use in statistical methods for sex estimations. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Family-Based Genetic Association for Molar-Incisor Hypomineralization.

    Science.gov (United States)

    Jeremias, Fabiano; Pierri, Ricardo A G; Souza, Juliana F; Fragelli, Camila Maria B; Restrepo, Manuel; Finoti, Livia S; Bussaneli, Diego G; Cordeiro, Rita C L; Secolin, Rodrigo; Maurer-Morelli, Claudia V; Scarel-Caminaga, Raquel M; Santos-Pinto, Lourdes

    2016-01-01

    Despite some evidence of genetic and environmental factors on molar-incisor hypomineralization (MIH), its aetiology remains unclear. This family-based genetic association study aimed more comprehensively to investigate the genetic carriage potentially involved in MIH development. DNA was obtained from buccal cells of 391 individuals who were birth family members of 101 Brazilian nuclear families. Sixty-three single nucleotide polymorphisms (SNPs) were investigated in 21 candidate genes related to amelogenesis using the TaqMan™ OpenArray™ Genotyping platform. All SNPs were genotyped in 165 birth family members unaffected by MIH, 96 with unknown MIH status and 130 affected individuals (50.7% with severe MIH). Association analysis was performed by the transmission/disequilibrium test (TDT), and statistical results were corrected using the false discovery rate. Significant results were obtained for SNPs rs7821494 (FAM83H gene, OR = 3.7; 95% CI = 1.75-7.78), rs34367704 (AMBN gene, OR = 2.7; 95% CI = 1.16-6.58), rs3789334 (BMP2 gene, OR = 2.9; 95% CI = 1.34-6.35), rs6099486 (BMP7 gene, OR = 2.2; 95% CI = 1.14-4.38), rs762642 (BMP4 gene, OR = 2.3; 95% CI = 1.38-3.65), rs7664896 (ENAM gene, OR = 2.1; 95% CI = 1.19-3.51), rs1711399 (MMP20 gene, OR = 0.4; 95% CI = 0.20-0.72), rs1711423 (MMP20 gene, OR = 2.1; 95% CI = 1.18-3.61), rs2278163 (DLX3 gene, OR = 2.8; 95% CI = 1.26-6.41), rs6996321 (FGFR1 gene, OR = 2.7; 95% CI = 1.20-5.88), and rs5979395 (AMELX gene, OR = 11.7; 95% CI = 1.63-84.74). Through this family-based association study, we concluded that variations in genes related to amelogenesis were associated with the susceptibility to develop MIH. This result is in agreement with the multifactorial idea of the MIH aetiology, but further studies are necessary to investigate more thoroughly the factors that could influence MIH. © 2016 S. Karger AG, Basel.

  11. Fusion of a primary mandibular lateral incisor and canine: A rarity

    Directory of Open Access Journals (Sweden)

    Treville Pereira

    2017-01-01

    Full Text Available Fusion is a developmental anomaly of dental hard tissues characterized by the union of two adjacent teeth. It may be complete with the formation of an abnormally large tooth or incomplete with the union of crowns or roots only. The exact cause is still unknown. This report describes a case of unilateral fusion of the primary lateral incisor and canine in a 6-year-old female patient who accompanied her parents for dental treatment and later had a checkup herself during one of the visits to the dental clinic. Medical history was noncontributory while there was no family history of dental anomalies. An intraoral examination revealed that mandibular right primary lateral incisor was fused to the primary canine. The permanent central incisors were erupting lingually. The intraoral periapical radiograph showed a bifid pulp chamber with a normal-sized root canal. Since the tooth was noncarious, a preventive approach with a periodic follow-up was planned.

  12. Dental anomalies in an orthodontic patient population with maxillary lateral incisor agenesis.

    Science.gov (United States)

    Citak, Mehmet; Cakici, Elif Bahar; Benkli, Yasin Atakan; Cakici, Fatih; Bektas, Bircan; Buyuk, Suleyman Kutalmış

    2016-01-01

    The purpose of this study was to evaluate the prevalence of dental anomalies in a subpopulation of orthodontic patients with agenesis of maxillary lateral incisors (MLI). The material of the present study included the records of the 1964 orthodontic patients. Panoramic radiographs and dental casts were used to analyze other associated eight dental anomalies, including agenesis of other teeth, dens invaginatus, dens evaginatus, peg shaped MLI, taurodontism, pulp stone, root dilaceration and maxillary canine impaction. Out of the 1964 patients examined, 90 were found to have agenesis of MLI, representing a prevalence of 4.6%. The most commonly found associated-anomalies were agenesis of other teeth (23.3%), peg-shaped MLIs (15.6%), taurodontism (42.2%), and dilacerated teeth (18.9%). Permanent tooth agenesis, taurodontism, peg-shaped maxillary lateral incisor, and root dilacerations are frequently associated with maxillary lateral incisor agenesis.

  13. Prevalence of maxillary lateral incisor agenesis and associated skeletal characteristics in an orthodontic patient population.

    Science.gov (United States)

    Bassiouny, Dalia S; Afify, Ahmed R; Baeshen, Hosam A; Birkhed, Dowen; Zawawi, Khalid H

    2016-08-01

    This study was aimed to investigate the prevalence of maxillary lateral incisor agenesis and associated skeletal characteristics in an orthodontic patient population. The records of the 1066 patients seeking orthodontic treatment were screened for maxillary lateral incisor agenesis (MLIA). The following data were recorded for each subject: age; gender; unilateral or bilateral agenesis of MLI and side. The lateral cephalogram of each subject with MLIA was digitally traced. The data were compared to age-matched control orthodontic patients with skeletal Class I. The prevalence of maxillary lateral incisor agenesis was 4.9% (52 patients) in which 63.5% were females. There was a significant difference between MLIA patients and controls in sagittal relationships (ANB, Wits, AB plane, angle of convexity and Co-A/Co-Gn differential analyses) p agenesis showed a significant tendency for skeletal Class III compared with the Class I control. This could be attributed to maxillary hypoplasia/retrognathia.

  14. Dental anomalies in an orthodontic patient population with maxillary lateral incisor agenesis

    Directory of Open Access Journals (Sweden)

    Mehmet Citak

    Full Text Available ABSTRACT Introduction: The purpose of this study was to evaluate the prevalence of dental anomalies in a subpopulation of orthodontic patients with agenesis of maxillary lateral incisors (MLI. Methods: The material of the present study included the records of the 1964 orthodontic patients. Panoramic radiographs and dental casts were used to analyze other associated eight dental anomalies, including agenesis of other teeth, dens invaginatus, dens evaginatus, peg shaped MLI, taurodontism, pulp stone, root dilaceration and maxillary canine impaction. Results: Out of the 1964 patients examined, 90 were found to have agenesis of MLI, representing a prevalence of 4.6%. The most commonly found associated-anomalies were agenesis of other teeth (23.3%, peg-shaped MLIs (15.6%, taurodontism (42.2%, and dilacerated teeth (18.9%. Conclusion: Permanent tooth agenesis, taurodontism, peg-shaped maxillary lateral incisor, and root dilacerations are frequently associated with maxillary lateral incisor agenesis.

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

    Directory of Open Access Journals (Sweden)

    Arezoo Jahanbin

    2014-06-01

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

  16. Multidisciplinary approach for the aesthetic treatment of maxillary lateral incisors agenesis: thinking about implants?

    Science.gov (United States)

    de Avila, Érica Dorigatti; de Molon, Rafael Scaf; de Assis Mollo, Francisco; de Barros, Luiz Antonio Borelli; Capelozza Filho, Leopoldino; de Almeida Cardoso, Mauricio; Cirelli, Joni Augusto

    2012-11-01

    Missing maxillary lateral incisors create an esthetic problem with specific orthodontic and prosthetic considerations. Implants are commonly used to replace congenitally missing lateral incisors in adolescent orthodontic patients. However, an interdisciplinary approach should be observed during the diagnosis, prognosis, and treatment plan to provide a result with good predictability and meet the esthetic and functional expectations of the patient. The present study describes a case of a young patient with tooth agenesis of maxillary lateral incisors, which was conducted with an integrated planning. After 5-year follow-up of 2 fixed implant-supported prostheses, clinical and radiographic examination showed the treatment to be successful. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Dens invaginatus with necrotic pulp in a right maxillary lateral incisor with preserved vitality.

    Science.gov (United States)

    Alessandro, Lanza; Fabrizio, Di Francesco; Gennaro, De Marco; Dario, Di Stasio; Eugenio, Guidetti; Letizia, Perillo; Luigi, Femiano; Felice, Femiano

    2018-01-01

    Dens invaginatus (DI) is a dental malformation occurring in several morphologic types. Consequently, treatment of teeth affected by DI can get complicated because of the complex root canal anatomy. The aim is to describe how to manage a rare report of a DI with necrotic pulp held within the vital pulp of a maxillary lateral incisor. Oral fistula was found on the buccal mucosa of the apex of the vital maxillary lateral incisor with a DI having necrotic pulp. Endodontic treatment of the maxillary lateral incisor and of the tract canal of DI was realized. Clinical disappearance of oral sinus tract was observed after 10 days. On the contrary, the disappearance of radiolucent area occurred after 6 months. A proper and prompt diagnosis is necessary to carry out effective prevention protocols or prevent consequences generating nonrecoverable endo-perio diseases.

  18. UNUSUAL CASE OF A MAXILLARY FIRST INCISOR WITH TWO ROOT CANALS.

    Directory of Open Access Journals (Sweden)

    Janet Kirilova

    2014-07-01

    Full Text Available Introduction: Maxillary central incisors usually have one root with one root canal. The cases with two root canals are extremely rare. Purpose: The aim was to present an unusual case of a maxillary first incisor with two root canals and the methods of treatment. Material and methods: The 48-year old patient had a painful swelling above the first maxillary incisor. The diagnosis was Periodontitis chronica granulomatosa diffusa exacerbata. After exploration of the pulp chamber, the inspection with an operating microscope was found two root canals. The lesion was covered to periapical and the part of marginal periodontium. The decision was taken of combined endodontic and surgery treatment. Results and discussion: After 7-year follow-up, there was a healing of the lesions and no recurrence. Conclusions: The combined endodontic and surgery treatment was successful choice for preservation of the tooth.

  19. The Use of Cone Beam Computed Tomography (CBCT to Determine Supernumerary and Impacted Teeth Position in Pediatric Patients: A Case Report

    Directory of Open Access Journals (Sweden)

    Hossein Nematolahi

    2013-03-01

    Full Text Available A case of a compound odontoma which caused delayed eruption of right maxillary central incisor in a ten year old girl is presented with clinical and radiographic findings. The patient presented with complaint of a hard painless swelling in the right anterior region of the maxilla and absence of right maxillary central incisor. After clinical examination, periapical and occlusal radiographs of the mentioned region were taken. Impacted maxillary right central incisor was seen malformed shape on the intraoral radiographs. After taking a cone beam computed tomography (CBCT a compound odontoma associated with the labial aspect of impacted maxillary right central incisor was diagnosed and then removed by simple local excision under local anesthesia. The removal of the odontoma was followed by forced eruption of the impacted central incisor. After three months the tooth returned to its original position.

  20. Unusual Transalveolar and Transmuco-Gingival Root Avulsion of a Fractured Primary Central Incisor: A Case with an 8-Year Follow-Up

    OpenAIRE

    Ferr?s-Amat, E.; D?az-Mart?nez, C.; Herrera-Mart?nez, S.; Maura-Solivellas, I.; Ferr?s-Padr?, E.

    2015-01-01

    The purpose of this unique case report is to describe a very unusual dentoalveolar fracture associated with avulsion of the near-complete root. A 3-year-old male patient came for consultation after a dentoalveolar trauma with a “fragment that looks like canine” found in his mouth by his mother. This boy suffered root fracture of the upper primary central right incisor, accompanied by transalveolar and transmuco-gingival avulsion of the tooth root fragment, leaving the crown in its position in...

  1. Comparative analysis of the stress distribution in five anatomical types of maxillary central incisor.

    Science.gov (United States)

    Sun, Lei; Wu, Xifeng; Li, Yang; Lin, Zhenyan; Xu, Duoling; Lin, Xuan; Gao, Yongbo

    2017-07-20

    The maxillary central incisor is one of the most important anatomical indicators in esthetics, and stress distribution may vary among its five anatomical views (labial, palatal, mesial, distal, and incisal). To compare stress distribution among the five anatomical views of the maxillary central incisor under loading force at five angles and to observe and analyze the stress distribution in the dentin and periodontal ligament. We established three-dimensional finite element models of the five different views, which simulated the bite force with a static load force at 0∘, 30∘, 45∘, 60∘, and 90∘. The stress and displacement values for the cementoenamel junction (CEJ)-apical labial, palatal, mesial, and distal and the equivalent stress values on the periodontal ligament of the maxillary central incisor were calculated. As the angle increased, the equivalent stress on the periodontal ligament, overall tooth displacement, equivalent stress, and displacement over the four views increased. The peaks of equivalent stress over the four views appeared within 0.8-17 mm below the CEJ, although all equivalent stress values decreased while approaching the peak. Within 1-19 mm below the CEJ, the equivalent stress over the M1 and P1 views of the maxillary central incisor decreased substantially. The peaks of the equivalent stress over the M1 and P1 views of the maxillary central incisor and their stress distribution were lower than those of the other three types. Our findings provided theoretical data on the biomechanics of this esthetically important tooth, which may be useful during implantation of missing maxillary central incisors.

  2. In Vivo Color Relationships Between the Maxillary Central Incisors and Canines as a Function of Age.

    Science.gov (United States)

    Falcone, Marie Elena; Kelly, J Robert; Rungruanganut, Patchanee

    2016-01-01

    It has long been taught that the hue of a patient can be taken from the canine and applied to other anterior teeth at a lower chroma. This concept does not appear to derive from published work. This study examined color relationships between in vivo maxillary central incisors and canines as a function of age. The L*a*b* values and VITA Classical shades of the maxillary central incisor and canine of 62 subjects were determined using a handheld spectrophotometer. Linear regression analysis and t tests were used to describe the relationships of the L*a*b* values of these teeth within each patient and as a function of age. Linear regression demonstrated a significant decrease in ΔE with age (P = .056). Patient age was greater when ΔE (central-canine) > 3.3 (average age = 38.8 years) than when ΔE < 3.3 (average age = 58.8 years) (t test; P = .19). ΔC decreases significantly with age (P < .001). ΔH demonstrated a trend to decrease as a function of age (P = .2). ΔL remained the same over time (P = .21). Changes with age were due to central incisor differences, while the canine remained constant. ΔE (incisor-canine) significantly decreases with age; mostly due to ΔC. The majority of changes for all three color coordinates are due to alterations in the central incisor. The majority of the patients in this study were found to have a different shade family (VITA Classical) for the central incisor and canine.

  3. The nose shape as a predictor of maxillary central and lateral incisor width.

    Science.gov (United States)

    Sülün, Tonguç; Ergin, Ugur; Tuncer, Necat

    2005-09-01

    One of the primary aspects of complete denture prosthodontics is determining the correct proportion for the maxillary central incisor width to the lateral incisor width. It has been suggested that the anatomy of the patient's nose is a reliable guide for deciding this ratio. The aim of this study was to test the hypothesis about the relationship between the shape of the nose and the proportion of the central incisor width (CIW) to the lateral incisor width (LIW). The CIW and LIW from a total of 138 subjects (73 males, 65 females) were measured intraorally. The interalar width (IAW) and the width of the root of the nose (WRN) were measured on standard photographs of the subjects. Spearman's rho test was used to analyze the correlation between the proportions of the CIW to the LIW and the IAW to the WRN. The Mann-Whitney Utest was applied to test for any possible gender differences. The IAW, the WRN, and the nose angle (NA) were statistically significantly wider in male subjects than in female subjects. The correlation between IAW/WRN, NA, and CIW/LIW was statistically significant only in female subjects. In the general population, the only statistically significant relationship was between CIW/LIW on the left side and IAW/WRN. Within the results of the IAW, WRN, and NA measurements, we suggest that males have wider, more triangular-shaped noses than females. The proportion of IAW to WRN seems to be a reliable guide for deciding the proportion of the maxillary central incisor width to the lateral incisor.

  4. Multiple supernumerary teeth associated with an impacted maxillary central incisor: Surgical and orthodontic management

    Directory of Open Access Journals (Sweden)

    Ramakrishna Yeluri

    2012-01-01

    Full Text Available Various anomalies in the size, shape, number, structure and eruption of the teeth are often observed clinical conditions. Supernumerary teeth can be found in almost any region of the dental arch, and most of the times they are asymptomatic, and are routinely found during radiographic evaluation. The most common cause of impacted maxillary incisors is the presence of the supernumerary teeth. This paper describes a case of multiple supernumerary teeth associated with an impacted permanent maxillary central incisor in an 11-year old child along with its surgical and orthodontic management.

  5. Multiple supernumerary teeth associated with an impacted maxillary central incisor: Surgical and orthodontic management.

    Science.gov (United States)

    Yeluri, Ramakrishna; Hegde, Manjunath; Baliga, Sudhindra; Munshi, Autar Krishen

    2012-04-01

    Various anomalies in the size, shape, number, structure and eruption of the teeth are often observed clinical conditions. Supernumerary teeth can be found in almost any region of the dental arch, and most of the times they are asymptomatic, and are routinely found during radiographic evaluation. The most common cause of impacted maxillary incisors is the presence of the supernumerary teeth. This paper describes a case of multiple supernumerary teeth associated with an impacted permanent maxillary central incisor in an 11-year old child along with its surgical and orthodontic management.

  6. Modified Quad Helix for Correction of Severely Rotated Incisors in Cleft Cases

    Directory of Open Access Journals (Sweden)

    Aneesha Ashok Shetty

    2014-01-01

    Full Text Available Clefts of the lip, alveolus and/or palate are often associated with several dental anomalies, the most common of which are severely rotated maxillary incisors. Patients with such congenital deformities seek orthodontic treatment as early as possible, for an esthetic as well as psychosocial benefit. Here, a new clinical technique is demonstrated for correction of a severely rotated maxillary central incisor which can be carried out in the mixed dentition phase itself, by modifying a commonly used palatal expansion appliance: the quad helix.

  7. Dentigerous cyst associated with a maxillary permanent lateral incisor: Case report and literature review

    Directory of Open Access Journals (Sweden)

    B K Ramnarayan

    2008-01-01

    Full Text Available Trauma to deciduous teeth can have severe consequences. Dentigerous cysts are common developmental odontogenic cysts of the jaws. They are associated with the crown of an unerupted/impacted or developing tooth. Reported cases most commonly involve mandibular third molars and maxillary canines. They rarely involve the incisors. The condition occurs predominantly in the second and third decades of life. We report a case of dentigerous cyst involving the permanent maxillary lateral incisor, which developed as a consequence to trauma to the deciduous predecessor. The pathogenesis and clinical and radiologic features are discussed.

  8. Endodontic treatment of a periradicular lesion on an invaginated type III mandibular lateral incisor

    Directory of Open Access Journals (Sweden)

    Carvalho-Sousa B

    2009-01-01

    Full Text Available Dens invaginatus (DI, commonly known as dens in dente, is a developmental malformation of teeth that most commonly affects permanent maxillary incisor teeth. DI can present in a variety of forms, knowledge of which can usefully help in endodontic diagnosis and treatment. This article reports on an unusual case of DI type III with a periradicular lesion in a mandibular lateral incisor. Non-surgical endodontic treatment was performed and resolution of the periradicular lesion was observed at 1 year follow-up. Clinical considerations and treatment are discussed and reported.

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

    Science.gov (United States)

    Machado, Gislana Braga

    2015-01-01

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

  10. Treatment of Class II subdivision malocclusion with congenitally missing upper lateral incisors: A case report

    Directory of Open Access Journals (Sweden)

    Siddharth Mehta

    2014-01-01

    Full Text Available Orthodontic treatment for patients with unilateral or bilateral congenitally missing lateral incisor poses a challenge mainly with regard to treatment planning. The use of a diagnostic setup is one of the most important aids in the decision-making process. Two alternatives, orthodontic space closure or space opening for prosthetic replacement exist. The present case report shows use of the microimplant for unilateral upper molar distalization and space closure in a Class-II division 1 subdivision malocclusion case with bilateral congenitally missing upper lateral incisors.

  11. Rehabilitation of molar-incisor hypomineralization (MIH) complicated with localized tooth surface loss: a case report.

    Science.gov (United States)

    Lam, Walter Y H; Ho, Edward H T; Pow, Edmond H N

    2014-05-01

    Molar-incisor hypomineralization (MIH) is a developmental enamel hypomineralized condition characteristically involving the first permanent molars and sometimes also the incisors. The affected teeth are predisposed to tooth surface loss (TSL) which may not only compromise the esthetics and function but also endanger the pulp and longevity of the teeth. This report describes the management of a patient with MIH complicated with localized TSL and lack of occlusal clearance due to dentoalveolar compensation. The atypical TSL pattern involved all anterior teeth and required the placement of Dahl appliances on both arches.

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

    Directory of Open Access Journals (Sweden)

    Gislana Braga Machado

    2015-06-01

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

  13. Delayed eruption of maxillary permanent central incisors as a consequence of mesiodens: a surgical re-treatment approach.

    Science.gov (United States)

    Moraes, Renata Simões; Farinhas, João Alfredo; Gleiser, Rogerio; Primo, Laura Guimarães

    2004-01-01

    The presence of mesiodens can cause some clinical problems. This paper reports a case of delayed eruption of permanent central incisors in a nine-year-old male as a consequence of a mesiodens and three surgical approaches prior to the eruption of incisors, which occurred after the third surgery when the crown was exposed and submitted to a gentle luxation.

  14. Dental Items of Interest: The Case of Delphic Sibyl by Michelangelo: Solitary Median Maxillary Central Incisor or Mesiodens.

    Science.gov (United States)

    Perciaccante, Antonio; Coralli, Alessia

    2015-01-01

    A case of an anomaly in the maxillary dental arch on "Delphic Sibyl," a fresco by Michelangelo is reported. An accurate analysis of this fresco shows a single incisor tooth is present precisely in the midline. We hypothesize that it may be a case of solitary median maxillary central incisor (SMMCI) and discuss the differential diagnosis with another similar anomaly--the mesiodens.

  15. 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....

  16. Autotransplantation of a Supernumerary Tooth to Replace a Misaligned Incisor with Abnormal Dimensions and Morphology: 2-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    R. Ebru Tirali

    2013-01-01

    Full Text Available Autotransplantation is a viable treatment option to restore esthetics and function impaired by abnormally shaped teeth when a suitable donors tooth is available. This paper describes the autotransplantation and 2-year follow-up of a supernumerary maxillary incisor as a replacement to a misaligned maxillary incisor with abnormal crown morphology and size. The supernumerary incisor was immediately autotransplanted into the extraction site of the large incisor and was stabilized with a bonded semirigid splint for 2 weeks. Fixed orthodontic therapy was initiated 3 months after autotransplantation. Ideal alignment of the incisors was accomplished after 6 months along with radiographic evidence of apical closure and osseous/periodontal regeneration. In autogenous tooth transplantation, a successful clinical outcome can be achieved if the cases are selected and treated properly.

  17. Gender differences in the form of maxillary central incisors analyzed using AutoCAD software.

    Science.gov (United States)

    Brunetto, Juliana; Becker, Mirian Marly; Volpato, Claudia A Maziero

    2011-08-01

    Female teeth are considered more rounded and male teeth more quadrangular. Although lacking in scientific support, this theory helps in selecting the mold of artificial teeth for dentures. Parameters that are more reliable are sought to determine gender differences in tooth form. The purpose of this study was to assess possible differences between genders in terms of tooth form: oval, triangular, or quadrangular. The sample comprised 433 subjects with a mean age of 15 years selected from a population of Brazilian high school students. The maxillary right central incisor (MCI) of each subject was photographed. The images were adjusted to standardize the long axis of the tooth in the vertical position. The AutoCAD computer program was used to analyze graphically the geometric form of the tooth. According to analysis results, form was classified as oval, triangular, or quadrangular. Intraexaminer consistency was analyzed by using linear correlation coefficient and Bland Altman analysis. The relationship between gender and tooth form was analyzed by chi-square and linear regression (α=.05). In women, the form was 57.73% (n=127) oval, 23.54% (n=52) triangular, and 18.64% (n=41) quadrangular; while in men, the form was 54.93% (n=117) oval, 36.15% (n=77) triangular, and 8.92% (n=19) quadrangular (P<.001). The oval form was the most prevalent in both genders. However, the triangular form was more common in men than in women, and the quadrangular form more frequent in women than in men. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  18. Numerical simulation and structural optimization of the inclined oil/water separator.

    Directory of Open Access Journals (Sweden)

    Liqiong Chen

    Full Text Available Improving the separation efficiency of the inclined oil/water separator, a new type of gravity separation equipment, is of great importance. In order to obtain a comprehensive understanding of the internal flow field of the separation process of oil and water within this separator, a numerical simulation based on Euler multiphase flow analysis and the realizable k-ε two equation turbulence model was executed using Fluent software. The optimal value ranges of the separator's various structural parameters used in the numerical simulation were selected through orthogonal array experiments. A field experiment on the separator was conducted with optimized structural parameters in order to validate the reliability of the numerical simulation results. The research results indicated that the horizontal position of the dispenser, the hole number, and the diameter had significant effects on the oil/water separation efficiency, and that the longitudinal position of the dispenser and the position of the weir plate had insignificant effects on the oil/water separation efficiency. The optimal structural parameters obtained through the orthogonal array experiments resulted in an oil/water separation efficiency of up to 95%, which was 4.996% greater than that realized by the original structural parameters.

  19. New inclination changing eclipsing binaries in the Magellanic Clouds

    Science.gov (United States)

    Juryšek, J.; Zasche, P.; Wolf, M.; Vraštil, J.; Vokrouhlický, D.; Skarka, M.; Liška, J.; Janík, J.; Zejda, M.; Kurfürst, P.; Paunzen, E.

    2018-01-01

    Context. Multiple stellar systems are unique laboratories for astrophysics. Analysis of their orbital dynamics, if well characterized from their observations, may reveal invaluable information about the physical properties of the participating stars. Unfortunately, there are only a few known and well described multiple systems, this is even more so for systems located outside the Milky Way galaxy. A particularly interesting situation occurs when the inner binary in a compact triple system is eclipsing. This is because the stellar interaction, typically resulting in precession of orbital planes, may be observable as a variation of depth of the eclipses on a long timescale. Aims: We aim to present a novel method to determine compact triples using publicly available photometric data from large surveys. Here we apply it to eclipsing binaries (EBs) in Magellanic Clouds from OGLE III database. Our tool consists of identifying the cases where the orbital plane of EB evolves in accord with expectations from the interaction with a third star. Methods: We analyzed light curves (LCs) of 26121 LMC and 6138 SMC EBs with the goal to identify those for which the orbital inclination varies in time. Archival LCs of the selected systems, when complemented by our own observations with Danish 1.54-m telescope, were thoroughly analyzed using the PHOEBE program. This provided physical parameters of components of each system. Time dependence of the EB's inclination was described using the theory of orbital-plane precession. By observing the parameter-dependence of the precession rate, we were able to constrain the third companion mass and its orbital period around EB. Results: We identified 58 candidates of new compact triples in Magellanic Clouds. This is the largest published sample of such systems so far. Eight of them were analyzed thoroughly and physical parameters of inner binary were determined together with an estimation of basic characteristics of the third star. Prior to our

  20. Aerodynamics of wing-assisted incline running in birds.

    Science.gov (United States)

    Tobalske, Bret W; Dial, Kenneth P

    2007-05-01

    Wing-assisted incline running (WAIR) is a form of locomotion in which a bird flaps its wings to aid its hindlimbs in climbing a slope. WAIR is used for escape in ground birds, and the ontogeny of this behavior in precocial birds has been suggested to represent a model analogous to transitional adaptive states during the evolution of powered avian flight. To begin to reveal the aerodynamics of flap-running, we used digital particle image velocimetry (DPIV) and measured air velocity, vorticity, circulation and added mass in the wake of chukar partridge Alectoris chukar as they engaged in WAIR (incline 65-85 degrees; N=7 birds) and ascending flight (85 degrees, N=2). To estimate lift and impulse, we coupled our DPIV data with three-dimensional wing kinematics from a companion study. The ontogeny of lift production was evaluated using three age classes: baby birds incapable of flight [6-8 days post hatching (d.p.h.)] and volant juveniles (25-28 days) and adults (45+ days). All three age classes of birds, including baby birds with partially emerged, symmetrical wing feathers, generated circulation with their wings and exhibited a wake structure that consisted of discrete vortex rings shed once per downstroke. Impulse of the vortex rings during WAIR was directed 45+/-5 degrees relative to horizontal and 21+/-4 degrees relative to the substrate. Absolute values of circulation in vortex cores and induced velocity increased with increasing age. Normalized circulation was similar among all ages in WAIR but 67% greater in adults during flight compared with flap-running. Estimated lift during WAIR was 6.6% of body weight in babies and between 63 and 86% of body weight in juveniles and adults. During flight, average lift was 110% of body weight. Our results reveal for the first time that lift from the wings, rather than wing inertia or profile drag, is primarily responsible for accelerating the body toward the substrate during WAIR, and that partially developed wings, not yet

  1. Percentiles relative to maxillary permanent canine inclination by age: a radiologic study.

    Science.gov (United States)

    Alessandri Bonetti, Giulio; Zanarini, Matteo; Danesi, Margherita; Parenti, Serena Incerti; Gatto, Maria Rosaria

    2009-10-01

    Few studies have investigated developmental norms for maxillary permanent canine eruption. In this observational cross-sectional study, we aimed to provide an age-related description of the percentiles relative to canine inclination in a large sample of nonorthodontic patients. Associations between inclination and sector were also analyzed. Canine inclination and sector location were measured on 1020 panoramic radiographs obtained from subjects of white ancestry aged between 8 and 11 years not seeking orthodontic treatment. The total sample comprised 2037 canines. Canine inclination increases between 8 and 9 years and decreases between 9 and 11 years. The greatest value for each percentile is at 9 years. A linear model should be hypothesized for differences in canine inclination between 2 successive ages in correspondence to each percentile. The proportion of sector 2 canines decreases and that of sector 1 increases with age. In the same age group, the inclination generally decreases as the sector decreases. Percentiles by age show the average canine inclination in a certain population. Further studies are required to verify whether percentiles can be a diagnostic aid for determining normal canine inclination at a given age and for quantifying the risk of canine impaction or adjacent root resorption.

  2. How do the substrate reaction forces acting on a gecko's limbs respond to inclines?

    Science.gov (United States)

    Wang, Zhouyi; Dai, Zhendong; Li, Wei; Ji, Aihong; Wang, Wenbao

    2015-02-01

    Locomotion is an essential character of animals, and excellent moving ability results from the delicate sensing of the substrate reaction forces (SRF) acting on body and modulating the behavior to adapt the motion requirement. The inclined substrates present in habitats pose a number of functional challenges to locomotion. In order to effectively overcome these challenges, climbing geckos execute complex and accurate movements that involve both the front and hind limbs. Few studies have examined gecko's SRF on steeper inclines of greater than 90°. To reveal how the SRFs acting on the front and hind limbs respond to angle incline changes, we obtained detailed measurements of the three-dimensional SRFs acting on the individual limbs of the tokay gecko while it climbed on an inclined angle of 0-180°. The fore-aft forces acting on the front and hind limbs show opposite trends on inverted inclines of greater than 120°, indicating propulsion mechanism changes in response to inclines. When the incline angles change, the forces exerted in the normal and fore-aft directions by gecko's front and hind limbs are reassigned to take full advantage of limbs' different roles in overcoming resistance and in propelling locomotion. This also ensures that weight acts in the angle range between the forces generated by the front and hind limbs. The change in the distribution of SRF with a change in the incline angle is directly linked to the favorable trade-off between locomotive maneuverability and stability.

  3. Variation of the Friction Coefficient for a Cylinder Rolling down an Inclined Board

    Science.gov (United States)

    Yan, Zixiang; Xia, Heming; Lan, Yueheng; Xiao, Jinghua

    2018-01-01

    A cylinder rolling down an inclined board is a commonly seen and interesting object to study and it is also easy to experiment with and model. Following what has become a popular practice, we use smartphones to measure the angular acceleration of a cylinder rolling down a plane of different inclining angles. The friction force deviates from the…

  4. The effect of surfactants on upward air-water pipe flow at various inclinations

    NARCIS (Netherlands)

    van Nimwegen, A.T.; Portela, L.; Henkes, R.A.W.M.

    2016-01-01

    In this work, we extend our previous efforts on the effect of surfactants on air-water flow in a vertical pipe by also considering pipe inclinations between 20° (with respect to horizontal) and vertical. For air-water flow, independent of the inclination, there is a regular annular flow at large

  5. Comparison of normal permanent and primary dentition sagittal tooth-crown inclinations of Japanese females.

    Science.gov (United States)

    Inada, Emi; Saitoh, Issei; Hayasaki, Haruaki; Iwase, Yoko; Kubota, Naoko; Takemoto, Yoshihiko; Yamasaki, Youichi

    2012-01-01

    The purpose of this study was to clarify the characteristics of permanent and primary tooth-crown inclinations. Landmark points from cephalograms and dental casts of two groups; 23 women (mean 20.3 +/- 3.3 years) and 11 girls (mean 5.2 +/- 0.1 years) were digitized, and the coordinates were integrated and transformed to a standardized plane. The 3-dimensional crown inclinations were projected on the sagittal plane, and the angles between the tooth vectors and the FH plane were calculated. An independent-group t-test was used to test for group differences of each tooth inclination, and correlation coefficients were generated for the inclination angles among the permanent and primary teeth. Most maxillary tooth-crown inclinations showed significant age-related differences, while only the second premolar and primary second molar differed significantly in the mandible. The maxillary molars were parallel to the corresponding mandibular molars and correlated with each other, but the primary molars were not. Significant correlations were found between inclinations of most permanent teeth, but not the primary teeth. Maxillary tooth-crown inclinations change during growth, but tooth-crown inclinations of the mandibular teeth do not.

  6. Space Station Freedom assembly and operation at a 51.6 degree inclination orbit

    Science.gov (United States)

    Troutman, Patrick A.; Brewer, Laura M.; Heck, Michael L.; Kumar, Renjith R.

    1993-01-01

    This study examines the implications of assembling and operating Space Station Freedom at a 51.6 degree inclination orbit utilizing an enhanced lift Space Shuttle. Freedom assembly is currently baselined at a 220 nautical mile high, 28.5 degree inclination orbit. Some of the reasons for increasing the orbital inclination are (1) increased ground coverage for Earth observations, (2) greater accessibility from Russian and other international launch sites, and (3) increased number of Assured Crew Return Vehicle (ACRV) landing sites. Previous studies have looked at assembling Freedom at a higher inclination using both medium and heavy lift expendable launch vehicles (such as Shuttle-C and Energia). The study assumes that the shuttle is used exclusively for delivering the station to orbit and that it can gain additional payload capability from design changes such as a lighter external tank that somewhat offsets the performance decrease that occurs when the shuttle is launched to a 51.6 degree inclination orbit.

  7. Efficient light trapping in silicon inclined nanohole arrays for photovoltaic applications

    Science.gov (United States)

    Deng, Can; Tan, Xinyu; Jiang, Lihua; Tu, Yiteng; Ye, Mao; Yi, Yasha

    2018-01-01

    Structural design with high light absorption is the key challenge for thin film solar cells because of its poor absorption. In this paper, the light-trapping performance of silicon inclined nanohole arrays is systematically studied. The finite difference time domain method is used to calculate the optical absorption of different inclination angles in different periods and diameters. The results indicate that the inclined nanoholes with inclination angles between 5° and 45° demonstrate greater light-trapping ability than their counterparts of the vertical nanoholes, and they also show that by choosing the optimal parameters for the inclined nanoholes, a 31.2 mA/cm2 short circuit photocurrent density could be achieved, which is 10.25% higher than the best vertical nanohole system and 105.26% higher than bare silicon with a thickness of 2330 nm. The design principle proposed in this work gives a guideline for choosing reasonable parameters in the application of solar cells.

  8. Experimental Study of Natural Convection Cooling of Vertical Cylinders with Inclined Plate Fins

    Directory of Open Access Journals (Sweden)

    Jong Bum Lee

    2016-05-01

    Full Text Available In this paper, natural convection from vertical cylinders with inclined plate fins is investigated experimentally for use in cooling electronic equipment. Extensive experimental investigations are performed for various inclination angles, fin numbers, and base temperatures. From the experimental data, a correlation for estimating the Nusselt number is proposed. The correlation is applicable when the Rayleigh number, inclination angle, and fin number are in the ranges 100,000–600,000, 30°–90°, and 9–36, respectively. Using the correlation, a contour map depicting the thermal resistance as a function of the fin number and fin thickness is presented. Finally, the optimal thermal resistances of cylinders with inclined plate fins and conventional radial plate fins are compared. It is found that that the optimal thermal resistance of the cylinder with inclined fins is 30% lower than that of the cylinder with radial plate fins.

  9. Numerical Analysis of Aerodynamic Characteristics of the Finned Surfaces with Cross-inclined Fins

    Directory of Open Access Journals (Sweden)

    Lagutin A. E.

    2016-12-01

    Full Text Available This paper presents results of numerical research and analyses air-side hydraulic performance of tube bundles with cross inclined fins. The numerical simulation of the fin-tube heat exchanger was performed using the Comsol Femlab software. The results of modeling show the influence of fin inclination angle and tube pitch on hydraulic characteristics of finned surfaces. A series of numerical tests were carried out for tube bundles with different inclination angles (γ =900, 850, 650, 60, the fin pitch u=4 mm. The results indicate that tube bundles with cross inclined fins can significantly enhance the average integral value of the air flow rate in channel between fins in comparison with conventional straight fins. Aerodynamic processes on both sides of modificated channel between inclined fins were analyzed. The verification procedures for received results of numerical modeling with experimental data were performed.

  10. Stability of film boiling on inclined plates and spheres

    Science.gov (United States)

    Aursand, Eskil; Hammer, Morten; Munkejord, Svend Tollak; Müller, Bernhard; Ytrehus, Tor

    2017-11-01

    In film boiling, a continuous sub-millimeter vapor film forms between a liquid and a heated surface, insulating the two from each other. While quite accurate steady state solutions are readily obtained, the intermediate Reynolds numbers can make transient analysis challenging. The present work is a theoretical study of film boiling instabilities. We study the formation of travelling waves that are a combination of Kelvin-Helmholtz and the Rayleigh-Taylor instabilities. In particular, we study how the nature of this process depends on the Reynolds number, the Bond number, and the inclination of the submerged heated plate. In addition we extend the analysis to the case of a submerged heated sphere. Modelling of the transient dynamics of such films is important for answering practical questions such as how instabilities affect the overall heat transfer, and whether they can lead to complete film boiling collapse (Leidenfrost point). This work has been financed under the MAROFF program. We acknowledge the Research Council of Norway (244076/O80) and The Gas Technology Centre NTNU-SINTEF (GTS) for support.

  11. Articular Eminence Inclination in Medieval and Contemporary Croatian Population

    Science.gov (United States)

    Kranjčić, Josip; Šlaus, Mario; Vodanović, Marin; Peršić, Sanja; Vojvodić, Denis

    2016-12-01

    Articular eminence inclination (AEI) of the temporomandibular joint leads the mandible in its movements. Therefore, the aim of the present study was to determine AEI values in medieval (MP) and recent (RP) Croatian population. The study was carried out on two groups of specimens: first group with 30 MP human dry skulls, while the other, serving as control group consisted of 137 dry skulls. The AEI was measured on lateral digital skull images as the angle between the best fi t line drawn along the posterior wall of the articular eminence and the Frankfurt horizontal plane. No statistically significant (p>0.05) differences between the left and right side AEI were found between MP skulls and RP skulls. The mean value of MP AEI was 45.5˚, with a range of 20.9˚-64˚. The mean RP AEI value was steeper (61.99˚), with a range of 30˚-94˚. Difference between the mean MP and RP AEI values was statistically significant (pmedieval time, and consequently different masticatory loads and forces.

  12. Evaluation of primary stability of inclined orthodontic mini-implants.

    Science.gov (United States)

    Inaba, Mizuki

    2009-09-01

    The aim of this study was to investigate the initial stability of mini-implants when placed slanting or perpendicular to the bone surface, and to examine the effects of differences in tractional direction. Titanium mini-implants were inserted into rabbit nasal bones, slanting (60 degrees , 120 degrees ) or perpendicular (90 degrees ) to the bone surface. These implants were then loaded with a force of approximately 2 N, using a NiTi coil spring. The mobilities on the traction and non-traction sides were assessed using the Periotest device immediately after placement and after traction for two weeks. Then, the tissues with the mini-implants were resected, and the contact between the bone and the implant was examined by electron microscopy. There was a tendency for the mobilities of the mini-implants at 60 degrees and 120 degrees to be smaller than those at 90 degrees when measured before and after traction. The bone-implant contact lengths at 60 degrees were significantly longer than those at 90 degrees . There was no significant difference in the bone-implant contact ratio among the different angles. Correlations were evident between implant mobility and contact length or contact ratio. It is concluded that in clinical practice, implants inclined to the bone surface tend to have better primary stability.

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

    Science.gov (United States)

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

    2012-01-01

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

  14. Association between the facial type and morphology of the upper central incisor in normal occlusion subjects.

    Science.gov (United States)

    Paranhos, Luiz Renato; Zaroni, Miller; Carli, João Paulo de; Okamoto, Roberta; Zogheib, Lucas Villaça; Torres, Fernando César

    2014-01-01

    The purpose of this study was to verify the association between the facial type and the morphology of the upper central incisor, to potentially provide a guide for artificial tooth selection in esthetic and prosthetic rehabilitation. The sample consisted of 51 lateral teleradiographs (lateral cephalometric radiographs) and cast models of subjects with a naturally optimal occlusion and at least four of the six keys of Andrews, for optimal occlusion. The facial type was defined by two cephalometric measurements (SN.Gn and SN.GoGn) and classified into dolichofacial, meso- facial and brachyfacial after digitizing the radiographs. The incisor morphology was classified into quadrangular, oval and triangular after 3D digitizing the models and evaluation of the images by 12 dentists. The evaluation between the examiners was performed by Kappa test. In order to test the differences between the variables, it was used a chi-square test (5%). No significant difference (p morphology of the upper central incisor, considering the methodology and population included in the present study. Using the facial type as a way to select the morphology of the upper central incisor proved to be inadequate in this study.

  15. Incidence of two canals in extracted mandibular incisors teeth of Saudi Arabian samples

    Directory of Open Access Journals (Sweden)

    Khalid S Al-Fouzan

    2012-01-01

    Full Text Available Aim: The purpose of this in vitro study is to provide clinical data on the presence of the second canal in mandibular incisor teeth of Saudi Arabian Samples. Materials and Methods: Eighty extracted human mandibular incisors were collected from Saudi patients. The teeth were accessed by small round bur then placed in 5.25% sodium hypochlorite for 24 hours to dissolve the organic debris. Indian ink was injected inside the root canal systems under negative pressure. The teeth were decalcified in 5% nitric acid for three days then dehydrated in different concentrations of ethyl alcohol. Following the decalcification process, the teeth were cleared in methyl salicylate and evaluated according to Vertucci′s classification. Result: Fifty six of both mandibular central and lateral incisor teeth (70% had type I canal configuration (one main canal and one main apical foramen, while the remaining 30% of the sample (24 teeth had a type III canal configuration (two separate canals and merged into one canal before exiting the tooth through single apical foramen. Conclusion : The incidence of two canals in mandibular incisor teeth is about one third of the examined Saudi Arabian samples with no difference between the centrals and laterals. The clinician should deal with these teeth as if they have two canals unless it is proved otherwise.

  16. Dentists' and parents' perceptions of health, esthetics, and treatment of maxillary primary incisors.

    Science.gov (United States)

    Woo, Dawn; Sheller, Barbara; Williams, Bryan; Mancl, Lloyd; Grembowski, David

    2005-01-01

    Dentists' and parents' assessment of primary maxillary incisors regarding attractiveness, perceived health, and treatment preferences were investigated in this study. Sample groups of 103 general dentists, 67 pediatric dentists, 97 parents of children in low-income families and 112 parents of children in high-income families completed questionnaires presenting color photographs and radiographs of maxillary incisors. Questions addressed treatment need, health beliefs, and demographics. All groups recognized grossly carious teeth and carious teeth with visible sinus tracts as unhealthy and unattractive. All agreed that grossly carious teeth warranted extraction (dentists = 92%, parents = 73%). For carious teeth with sinus tracts, dentists favored extraction and restorations while parents favored fluoride application. Dentists rated a dark incisor as healthy and not requiring treatment. Parents rated a dark incisor as neutral for attractiveness and health, but favored extraction or restoration. All groups found anterior steel crowns esthetically unacceptable. Trust of the dentist, pain for the child, and dentist skill was important for parents in treatment plan acceptance. A dentist's inexperience in pediatrics may result in a failure to diagnose or recognize the significance of some conditions. Proper parental education can better inform parents on dental conditions requiring prompt professional attention. Although parents today are more involved in clinical decision-making, they still rely on the dentist's expertise and advice.

  17. A new type of dental anomaly: molar-incisor malformation (MIM).

    Science.gov (United States)

    Lee, Hyo-Seol; Kim, Soo-Hyun; Kim, Seong-Oh; Lee, Jae-Ho; Choi, Hyung-Jun; Jung, Han-Sung; Song, Je Seon

    2014-07-01

    A molar-incisor malformation (MIM) is a newly discovered type of dental anomaly of the permanent first molars, deciduous second molars, and permanent maxillary central incisors. MIM anomalies of the permanent first molars and deciduous second molars may include normal crowns with a constricted cervical region and thin, narrow, and short roots, whereas the affected maxillary central incisors may exhibit a hypoplastic enamel notch near the cervical third of the clinical crown. Although the etiology of MIM remains to be determined, it is thought to be attributable to an epigenetic factor linked to brain- and central nervous system-related systemic diseases at around age 1 to 2 years. MIM teeth are associated with clinical problems such as impaction, early exfoliation, space loss, spontaneous pain, periapical abscess, and poor incisor esthetics. Children with MIM teeth should be observed closely with respect to their medical history, and dentists should formulate a wider-ranging treatment plan. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Multiple crown size variables of the upper incisors in patients with supernumerary teeth compared with controls

    NARCIS (Netherlands)

    Khalaf, K.; Smith, R. N.; Elcock, C.; Brook, A. H.

    2009-01-01

    Aims: As part of ongoing studies of the aetiology of dental anomalies the aims of this study were to identify multiple components of tooth size of the upper permanent incisors in 34 patients with supernumerary teeth and to compare them with those in a control group to determine whether the presence

  19. A Teething Problem: Artefactual X-Ray Appearances of Odontoid Fracture due to Superimposed Incisor

    Directory of Open Access Journals (Sweden)

    Matthew Crocker

    2012-01-01

    Full Text Available We report a case of artefactual C2 fracture caused by a superimposed incisor tooth in a seven-year-old boy. CT refuted the diagnosis. Trauma clinicians should be aware of this entity to guide correct interpretation of trauma X-rays.

  20. acquired incisor malocclusion in an adult rabbit buck. a case report

    African Journals Online (AJOL)

    Administrator

    osteodystrophy, tooth root or gum infections, trauma or other conditions that can distort the alignment of the teeth (Brown, 2001). Although dental malocclusion involving the incisor have long been reported in the United Kingdom and elsewhere (Brown, 2001), there is paucity of information on its occurrence in Nigeria.

  1. Interim Restorative Approach for the Management of Congenitally Missing Permanent Mandibular Incisors: Presentation of Three Cases

    Directory of Open Access Journals (Sweden)

    Prashanth Prakash

    2011-01-01

    Full Text Available Congenital missing of mandibular permanent incisors with retained primary incisors may jeopardize the esthetic appearance and psychological development of children, especially during the years of transition into adolescence. The retained primary teeth are necessary for the maintenance and normal development of alveolar bone, which in turn is essential for future definitive rehabilitation. In such situations, an interim restoration may be provided before any definitive treatment is given to comfort the young patient during this transition period. Interim restorations may include resin-modified additions to the existing teeth as well as more sophisticated restorations such as resin-retained bridge and removable partial dentures. However, this restoration differs for different clinical situations based on various factors such as age and patient compliance, and also consideration has to be given for the growth changes of the child. The aim of this present paper is to discuss the esthetic management of three cases with bilateral agenesis of permanent mandibular incisors and retained primary incisors with composite interim restoration.

  2. “Maxillary lateral incisor partial anodontia sequence”: a clinical entity with epigenetic origin

    Science.gov (United States)

    Consolaro, Alberto; Cardoso, Maurício Almeida; Consolaro, Renata Bianco

    2017-01-01

    ABSTRACT The relationship between maxillary lateral incisor anodontia and the palatal displacement of unerupted maxillary canines cannot be considered as a multiple tooth abnormality with defined genetic etiology in order to be regarded as a “syndrome”. Neither were the involved genes identified and located in the human genome, nor was it presumed on which chromosome the responsible gene would be located. The palatal maxillary canine displacement in cases of partial anodontia of the maxillary lateral incisor is potentially associated with environmental changes caused by its absence in its place of formation and eruption, which would characterize an epigenetic etiology. The lack of the maxillary lateral incisor in the canine region means removing one of the reference guides for the eruptive trajectory of the maxillary canine, which would therefore, not erupt and /or impact on the palate. Consequently, and in sequence, it would lead to malocclusion, maxillary atresia, transposition, prolonged retention of the deciduous canine and resorption in the neighboring teeth. Thus, we can say that we are dealing with a set of anomalies and multiple sequential changes known as sequential development anomalies or, simply, sequence. Once the epigenetics and sequential condition is accepted for this clinical picture, it could be called “Maxillary Lateral Incisor Partial Anodontia Sequence.” PMID:29364376

  3. Incisor morphology as an aid in the systematics of the South African ...

    African Journals Online (AJOL)

    T.J. Robinson. Present address: Division of Cytogenetics, Department of. Pediatrics, University of Texas Medical Branch, Galveston, Texas. 77550 U.S.A.. Received 16 March 1986; accepted 21 May 1986. The enamel folding responsible for the notched appearance of the labial or outer surface of the principal upper incisor.

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

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    Gupta Rakhi

    2007-01-01

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

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

    Science.gov (United States)

    Mishra, Apurva; Pandey, Ramesh K

    2016-01-01

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

  6. Unerupted maxillary central incisors: a case report and review of the ...

    African Journals Online (AJOL)

    The management involved clinical, radiographic and orthodontic assessment. A diagnosis of hyperplastic gingivae preventing ... Early removal of causative factors leads to better prognosis This mixed dentition anomaly of tooth eruption was conservatively managed by paedodontists. Keywords: Unerupted maxillary incisors, ...

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

    Directory of Open Access Journals (Sweden)

    Dolrudee Jumlongras

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

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

    Science.gov (United States)

    Gupta, Rakhi; Sivapathasundharam, B; Einstein, A

    2007-01-01

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

  9. Lip-to-incisor relationship and postorthodontic long-term stability of cover-bite treatment.

    NARCIS (Netherlands)

    Lapatki, B.G.; Baustert, D.; Schulte-Monting, J.; Frucht, S.; Jonas, I.E.

    2006-01-01

    OBJECTIVE: To investigate the impact of a persisting high lip line and other potential relapse-inducing factors on long-term stability of orthodontic correction of retroinclined maxillary central incisors. MATERIALS AND METHODS: Thirty-one cover-bite ("Deckbiss") patients with retroinclined

  10. Acquired incisor malocclusion in an adult rabbit buck. A case report ...

    African Journals Online (AJOL)

    A diagnosis of acquired incisor malocclusion was made based on the history, physical examination of the rabbit and postmortem examination of the skull. To the best of our knowledge, this appears to be the first reported case of this condition in Nigeria. It is suggested that the condition may be more common among rabbits ...

  11. Botulinum neurotoxin type A in the masseter muscle: effects on incisor eruption in rabbits.

    Science.gov (United States)

    Navarrete, Alfonso L; Rafferty, Katherine L; Liu, Zi Jun; Ye, Wenmin; Greenlee, Geoffrey M; Herring, Susan W

    2013-04-01

    Botulinum neurotoxins are responsible for the paralytic food poisoning, botulism. Commercial formulations such as botulinum neurotoxin type A are increasingly used for various conditions, including cosmetic recontouring of the lower face by injection of the large masseter muscles. The paralysis of a major muscle of mastication lowers occlusal force and thus might affect tooth eruption. The purpose of this study was to investigate the effects of unilateral masseter muscle injection of botulinum neurotoxin type A on the rate of eruption of incisors in a rabbit model. We hypothesized that the teeth would overerupt in an underloaded environment. Forty rabbits were injected with either botulinum neurotoxin type A or saline solution in 1 masseter muscle. Mastication and muscle force production were monitored, and incisor eruption rate was assessed by caliper measurement of grooved teeth. The injection of saline solution had no effect. The masseter muscle injected with botulinum neurotoxin type A showed a dramatic loss of force 3 weeks after injection despite apparently normal mastication. Incisor eruption rate was significantly decreased for the botulinum neurotoxin type A group, an effect attributed to decreased attrition. This study has implications for orthodontics. Although findings from ever-growing rabbit incisors cannot be extrapolated to human teeth, it is clear that botulinum neurotoxin type A caused a decrease in bite force that could influence dental eruption. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  12. A comparison of mandibular incisor proclination when using clear aligners and fixed labial orthodontic brackets

    OpenAIRE

    Hennessy, Joe

    2015-01-01

    The objective of this ‘2-arm parallel' clinical trial was to compare the mandibular incisor proclination produced by fixed labial appliances and 3rd generation clear aligners. TARA (Trinity’s Access to Research Archive) has a robust takedown policy. Please contact us if you have any concerns:

  13. Excess NF-kB induces ectopic odontogenesis in embryonic incisor epithelium

    Czech Academy of Sciences Publication Activity Database

    Blackburn, J.; Kawasaki, K.; Porntaveetus, T.; Kawasaki, M.; Otsuka-Tanaka, Y.; Miake, Y.; Ota, M. S.; Watanabe, M.; Hishinuma, M.; Nomoto, T.; Oommen, S.; Ghafoor, S.; Harada, F.; Nozawa-Inoue, K.; Maeda, T.; Peterková, Renata; Lesot, H.; Inoue, J.; Akiyama, T.; Schmidt-Ulrich, R.; Liu, B.; Hu, Y.; Page, A.; Ramírez, Á.; Sharpe, P. T.; Ohazama, A.

    2015-01-01

    Roč. 94, č. 1 (2015), s. 121-128 ISSN 0022-0345 R&D Projects: GA ČR GB14-37368G Institutional support: RVO:68378041 Keywords : incisor * tooth development Subject RIV: EA - Cell Biology Impact factor: 4.602, year: 2015

  14. Epidemiologic study of molar-incisor hypomineralization in 8-year-old Spanish children.

    Science.gov (United States)

    Garcia-Margarit, Miriam; Catalá-Pizarro, Monserrat; Montiel-Company, José María; Almerich-Silla, José Manuel

    2014-01-01

    To find the prevalence of molar-incisor hypomineralization (MIH) in a random sample of Spanish children, and to investigate the gender influence, distribution of defects, the treatment need associated and the relation between this disorder and dental caries. A cross-sectional study was carried out to determine MIH and caries prevalence in a randomly selected sample of 840 children from the 8-year-old population of the Valencia region of Spain. The examinations were carried out in the children's schools by one examiner who had previously been calibrated with the MIH diagnostic criteria of the European Academy of Paediatric Dentistry (EAPD). The percentage of children with MIH was 21.8% (95% CI 19.1-24.7), with a mean 3.5 teeth affected (2.4 molars and 1.1 incisors) been the maxillary molars the most affected. No gender differences were found. Of those with MIH, 56.8% presented lesions in both molars and incisors Children with MIH needed significantly more urgent and non-urgent treatment than those without MIH (chi-squared test P-value Molar-incisor hypomineralization prevalence is high in the child population of this region and equally affects boys and girls. The condition increases significantly the need of treatment of affected children. A significant association with dental caries was observed. © 2013 John Wiley & Sons Ltd, BSPD and IAPD.

  15. Treatment of an avulsed maxillary permanent central incisor by autotransplantation of a primary canine tooth.

    Science.gov (United States)

    Sönmez, D; Dalci, K; Tunç, E Sen

    2008-07-01

    To present a case in which an avulsed permanent maxillary central incisor was replaced by autotransplantation of a primary canine tooth. The present case describes transplantation of a primary canine tooth into the space left by an avulsed permanent maxillary central incisor after a delay of several days. After root canal treatment, the primary canine tooth was extracted and placed into the prepared socket. To provide better adaptation of the donor tooth, the recipient alveolar site was remodeled using surgical burs. Semi-rigid splinting was maintained for 15 days. The crown of the primary canine was reshaped with composite resin and with an interim prosthesis, preventing movement of the lateral incisor tooth into the space of the transplanted canine. After 24-month follow-up the autotransplanted primary canine showed ankylosis but the tooth was in an acceptable state. The use of permanent tooth autotransplantation has been well documented. However a literature search revealed only one case report on the autotransplantation of primary teeth. Long term results of primary tooth autotransplantation are scarce but the procedure in this case report could be considered as a temporary space maintainer for the treatment of a patient with a lost permanent incisor under 10 years of age. Success of primary tooth autotransplantation may be affected by several factors, such as case selection, extra oral time, surgical and endodontic procedures.

  16. Management of coronal fracture of traumatized central incisor: Report of two cases

    Directory of Open Access Journals (Sweden)

    Saad Mohammad Hassan Al-Zubaidi

    2017-01-01

    Full Text Available Two cases of traumatized permanent maxillary central incisors with complicated crown fractures of young patients are reported. Partial pulpotomy by Cvek technique was performed using mineral trioxide aggregate filling material. The tooth fragment was reattached to the tooth structure with composite resin. Follow-up revealed normal pulpal response, complete apical closer, and dentin bridge formation.

  17. Mandibular Symphyseal/Parasymphyseal Fracture with Incisor Tooth Loss: Preventing Lower Arch Constriction.

    Science.gov (United States)

    Rahpeyma, Amin; Khajehahmadi, Saeedeh; Abdollahpour, Somayeh

    2016-03-01

    Mandibular fractures are the second most common fractures of the face after the nasal bone. Mandibular symphyseal/parasymphyseal fracture comprises 15.6 to 29.3% of mandibular fractures. Tooth loss in the fracture line is a known phenomenon, but space loss has not been evaluated comprehensively in the literature. In a retrospective study, patients with mandibular symphyseal/parasymphyseal fractures, who had been treated from 2012 to 2013 in Mashhad University, Iran, Emdadi Hospital, were recalled. Patients with mandibular incisor tooth/teeth loss were included in the study. Space loss, the technique used to replace the lost tooth/teeth, upper and lower dental midline relationship, combination fracture or fractures in other facial skeleton, and type of treatment were evaluated. Of 98 patients with mandibular symphyseal/parasymphyseal fractures, 22.5% had incisor tooth/teeth loss. In this group, 73% had space loss. Only four patients had replaced the lost tooth/teeth. Dental midlines did not match each other in patients whose feature was evaluated. Open reduction and internal fixation with miniplates were used in symphyseal/parasymphyseal fractures except one. Space loss after mandibular symphyseal/parasymphyseal fracture with incisor tooth loss is a common error. The most important factor to prevent complications related to space loss following mandibular symphyseal/parasymphyseal fracture accompanying incisor tooth loss is space preservation.

  18. Fracture resistance of reattached incisor fragments with mini fibre-reinforced composite anchors.

    NARCIS (Netherlands)

    Fennis, W.M.M.; Kreulen, C.M.; Wolke, J.G.C.; Fokkinga, W.A.; Machado, C.; Creugers, N.H.J.

    2009-01-01

    OBJECTIVES: Fractured coronal fragments of incisors can be adhered to the remaining tooth with resin composite, but are prone to failure. This study explores whether mini fibre-reinforced composite (FRC) anchors increase fracture resistance of reattached fragments. METHODS: Forty-five extracted

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

    LENUS (Irish Health Repository)

    Stewart, C

    2009-01-01

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

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

    Science.gov (United States)

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

    2010-09-01

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

  1. A clinical study of formocresol pulpotomy versus root canal therapy of vital primary incisors.

    Science.gov (United States)

    Aminabadi, Naser Asl; Farahani, Ramin Mostofi Zadeh; Gajan, Esrafil Balayi

    2008-01-01

    Pulpotomy of primary incisors is a serious challenge due to the lack of a distinct boundary between the coronal and the radicular pulp and the inaccuracy of the clinical indication criteria. The aim of the present study is the clinical and radiographic evaluation of pulpotomy versus root canal therapy (RCT) of vital primary incisors. A total of 100 incisors in 50 patients (female: 27, male: 23) aged 3-4 years were allocated to formocresol pulpotomy (45 teeth) and RCT (46 teeth) using zinc oxide-eugenol. The radiographic and clinical evaluation of treatment outcomes was performed at 12 and 24 months post-operatively. A history of spontaneous pain, missing restorations, recurrent caries, mobility and percussion sensitivity, parulis or fistula, erythema, and swelling were recorded. Data analysis was performed based on two sample proportional test. The clinical success rate was 86.9% for pulpotomy and 95.6% for RCT (P > 0.05). The radiographic assessment exhibited no pathologic signs in 76.08% of pulpotomy group and 91.3% of RCT group and the difference was statistically significant (P < 0.05). The most common pathologic finding was periodontal widening followed by external/internal root resorption. Periapical radiolucency and fistula in pulpotomized teeth was significantly higher than in RCT-treated teeth (P < 0.05) It may be concluded that the root canal therapy of vital primary incisors may be efficiently substituted for the pulpotomy of these teeth.

  2. Distribution and structure of dental enamel in incisors of Tabby mice

    Czech Academy of Sciences Publication Activity Database

    Risnes, S.; Peterková, Renata; Lesot, H.

    2005-01-01

    Roč. 50, - (2005), s. 181-184 ISSN 0003-9969 R&D Projects: GA MŠk(CZ) OC B23.002; GA ČR GA304/02/0448 Institutional research plan: CEZ:AV0Z5039906 Keywords : enamel * incisor * mouse Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.288, year: 2005

  3. Changes in root lengths of maxillary incisors during orthodontic retention period

    Directory of Open Access Journals (Sweden)

    Ravanmehr H

    2006-01-01

    Full Text Available Background and Aim: External apical root resorption is a common iatrogenic consequence of orthodontic treatment. Much controversy exists in the literature about changes in root lengths at post treatment periods. Although many practitioners believe that resorption becomes stable after active treatment, quantitative data are scarce. The purpose of this study was to determine quantitative changes in root lengths of maxillary incisors during fixed orthodontic post treatment period, and to assess if it is influenced by gender and factors related to active treatment. Materials and Methods: This was a case cross over study, performed on 80 patients (52 females and 28 males aged between 13 and 22 years. At debonding stage and beginning of retention phase of fixed orthodontic treatment, Hawley type retainer was fabricated for maxillary arch. Periapical radiographs of maxillary incisors using standard parallel technique were obtained immediately after debonding, and 3 and 7 months later. Crown and root lengths of maxillary incisors were measured using computer program. Changes in root lengths were calculated considering correction factors. Also associations between some factors and the change in root lengths during post treatment periods were assessed. These included gender, type of treatment plan (non extraction/extraction, technique (standard edgewise/straight-wire edgewise and duration of active treatment (less than 2 years/2 years and more. T-test and 4-way ANOVA were used for statistical analysis with P0.05 as the limit of significance. Results: No significant relation was found between apical root resorption of maxillary central incisors and time elapsed after treatment. Significant relation was observed between apical root resorption of maxillary lateral incisors and the length of post treatment period. No significant relation was found between root length changes of maxillary incisors during post treatment period and gender, type of treatment

  4. A new 2 D bracket positioning gauge

    Directory of Open Access Journals (Sweden)

    Bhuwan Saklecha

    2017-01-01

    Full Text Available Bracket positioning is the basic premise of pre-adjusted system, which allows the teeth to be placed with a straight wire into an occlusal contact with an excellent mesiodistal inclination (tip and excellent faciolingual inclination (torque. Improper bracket placement may lead to poorly placed teeth and necessitate bracket repositioning and archwire adjustments. This can lead to an increased treatment time or poor occlusion. Therefore, a bracket positioning gauge has been designed using both the planes and evaluated for its accuracy in bonding of brackets. It was found that the gauge not only helped in the placement of brackets accurately, but also reduced chairside time.

  5. Distribution of Molar Incisor Hypomineralization in Malaysian Children Attending University Dental Clinic.

    Science.gov (United States)

    Hussein, A S; Faisal, M; Haron, M; Ghanim, A M; Abu-Hassan, M I

    2015-01-01

    Molar-Incisor Hypomineralization (MIH) is a condition of hypomineralized enamel of systemic origin affecting first permanent molars and frequently permanent incisors. It is considered a global problem and data from South-East Asian countries, including Malaysia are lacking. Hence the aim of this study were to investigate the distribution and severity of MIH in a group of children aged 7-12 year olds attending pediatric dental clinic at Faculty of Dentistry, Universiti Teknologi MARA (UiTM), Malaysia. Hundred and fifty four children age 7-12 year-old with mean age of 9.14 ±1.682 had their first permanent molars and permanent incisors were examined at Faculty of Dentistry, UiTM using European Academy of Paediatric Dentistry 2003 (EAPD) criteria for diagnosis of MIH. Children at least one first permanent molar affected were considered as having MIH. Data were recorded and statistically analysed using descriptive analysis and Chi square test. Twenty six of the total examined children (n=154) had MIH (16.9%). There was no statistical difference between males and females in the prevalence of MIH. However, a statistical significant difference was found by age groups. The first permanent molars were more frequently affected (58%) as compared to permanent incisors. Mandibular molars were to have the highest rate of MIH (15.5%). The right and left sides were equally affected. Mild defects were the most frequent lesion type (96.6%). This study revealed that MIH is a common condition (16.9%). Molars were more frequently affected than incisors with mild defects were the most common lesion status. Further studies on this defect amongst Malaysian children are worthwhile.

  6. Turbulent mixed convection in vertical and inclined flat channels with aiding flows

    Energy Technology Data Exchange (ETDEWEB)

    Poskas, P.; Vilemas, J.; Adomaitis, J.E.; Bartkus, G.

    1995-09-01

    This paper presents an experimental study of turbulent mixed convection heat transfer for aiding flows in a vertical ({phi}=90{degrees}), inclined ({phi}=60{degrees},30{degrees}), and horizontal ({phi}=0{degrees}) flat channels with symmetrical heating and a ratio of height h to width b of about 1:10 and with length about 4 m (x/2h about 44). The study covered Re from 4x10{sup 3} to 5x10{sup 4} and Gr{sub q} from 5x10{sup 7}to 3x10{sup 10}. For the upper wall, a region of impaired heat transfer was found for all angular positions (from vertical to horizontal) and for bottom wall the augmentation of heat transfer in comparison to forced convection was revealed in the region of {phi}=0{degrees}-60{degrees}. Different characteristic buoyancy parameters were found for regions of impaired and enhanced heat transfer. General relations are suggested to predict the heat transfer for fully-developed-flow conditions and different angular positions.

  7. Radiographic evaluation in clinical practice of the types and stage of incisor tooth resorption and hypercementosis in horses.

    Science.gov (United States)

    Henry, T J; Puchalski, S M; Arzi, B; Kass, P H; Verstraete, F J M

    2017-07-01

    There are several reports of incisor tooth resorption and hypercementosis in horses but, to date, studies have been limited in case numbers and to advanced lesions. Tooth resorption in other species is a radiographic diagnosis of types of resorption that are often identified before clinical signs. Our goal was to evaluate radiographically incisor tooth resorption in a large population of horses, utilising interpretation criteria from canine and human dentistry. To document and classify incisor tooth resorption and hypercementosis. Retrospective descriptive case series. Horses presented for routine dental care >5 years old were included only if owners were unaware of incisor pathology. Radiographs (three views) were obtained of the incisor teeth and incisor teeth resorption was classified according to the radiographic criteria described for man and dogs. Hypercementosis and its location were recorded. Tooth resorption was detected in 149 of 169 (88.2%) horses and 951 of 1952 (48.7%) of incisor teeth. The classification system used was applicable in 926 (97.2%) of 951 affected teeth. Hypercementosis was detected in 34 (20.1%) horses and 148 (7.6%) teeth. As horses increased in age, resorption and hypercementosis was more frequent; no significant differences were found among sex or breed categories. All horses with hypercementosis had resorption, but only 23.4% of horses with resorption had hypercementosis. Advanced (stage ≥3) resorption was detected in 159 (8.1%) teeth and 54 (32.0%) horses in an otherwise clinically healthy population. Certain horses' anatomy precluded isolation of the mandibular third incisor teeth from the canine teeth due to superimposition. Incisor tooth resorption, in particular external replacement resorption and external inflammatory resorption, is common in horses. Hypercementosis is consistently associated with resorption, but the inverse association is inconsistent. © 2016 EVJ Ltd.

  8. Revealing strong bias in common measures of galaxy properties using new inclination-independent structures

    Science.gov (United States)

    Devour, Brian M.; Bell, Eric F.

    2017-06-01

    Accurate measurement of galaxy structures is a prerequisite for quantitative investigation of galaxy properties or evolution. Yet, the impact of galaxy inclination and dust on commonly used metrics of galaxy structure is poorly quantified. We use infrared data sets to select inclination-independent samples of disc and flattened elliptical galaxies. These samples show strong variation in Sérsic index, concentration and half-light radii with inclination. We develop novel inclination-independent galaxy structures by collapsing the light distribution in the near-infrared on to the major axis, yielding inclination-independent 'linear' measures of size and concentration. With these new metrics we select a sample of Milky Way analogue galaxies with similar stellar masses, star formation rates, sizes and concentrations. Optical luminosities, light distributions and spectral properties are all found to vary strongly with inclination: When inclining to edge-on, r-band luminosities dim by >1 magnitude, sizes decrease by a factor of 2, 'dust-corrected' estimates of star formation rate drop threefold, metallicities decrease by 0.1 dex and edge-on galaxies are half as likely to be classified as star forming. These systematic effects should be accounted for in analyses of galaxy properties.

  9. Influence of Cusp Inclination and Type of Retention on Fracture Load of Implant-Supported Crowns.

    Science.gov (United States)

    Rocha, Cibele Oliveira de Melo; Longhini, Diogo; Pereira, Rodrigo de Paula; Arioli, João Neudenir

    2017-01-01

    There are few informations about the influence of cusp inclination on the fracture strength of implant-supported crowns. The study aimed to evaluate the influence of cusp inclination and retention type on fracture load in implant-supported metal-ceramic single crowns. Sixty crowns were made, classified as cemented and screw-retained with screw access hole (SAH) sealed or not. Standard (33°) and reduced (20°) cusp inclinations were tested for each group (n=10). To support crowns of a mandibular second molar, analogs of external hexagon implants 5.0 were used. The fracture load was measured in a universal testing machine EMIC DL2000 (10 kN load cell; 0.5 mm/min). Two-way ANOVA (retention and cusp inclination) followed by post hoc Tukey's honest significant difference test was used for the statistical analyses (a=0.05). Crowns with reduced cusp inclination exhibited significantly higher fracture load (pcrowns with standard cusp inclination. Cemented crowns showed significantly higher fracture load (pcrowns. The interaction among these factors was not significant (p>0.05) for the fracture load. The sealing of SAH did not influence the fracture load of screw-retained crowns (p>0.05). In conclusion, fracture load of implant-supported metal-ceramic crowns was influenced by retention and cusp inclination, and there was no influence of the sealing of SAH.

  10. Treating domestic sewage by Integrated Inclined-Plate-Membrane bio-reactor

    Science.gov (United States)

    Song, Li Ming; Wang, Zi; Chen, Lei; Zhong, Min; Dong, Zhan Feng

    2017-12-01

    Membrane fouling shorten the service life of the membrane and increases aeration rate for membrane surface cleaning. Two membrane bio-reactors, one for working and another for comparing, were set up to evaluate the feasibility of alleviating membrane fouling and improving wastewater treatment efficiency by integrating inclined-plate precipitation and membrane separation. The result show that: (1) Inclined-plate in reactor had a good effect on pollutant removal of membrane bioreactor. The main role of inclined-plate is dividing reactor space and accelerating precipitation. (2) Working reactor have better performance in COD, TN and TP removal, which can attribute to that working reactor (integrated inclined-plate-Membrane bioreactor) takes both advantages of membrane separation and biological treatment. When influent COD, TP and TN concentration is 163-248 mg/L, 2.08-2.81 mg/L and 24.38-30.49 mg/L in working reactor, effluent concentration is 27-35 mg/L, 0.53-0.59 mg/L and 11.28-11.56 mg/L, respectively. (3) Membrane fouling was well alleviated in integrated inclined-plate-Membrane bioreactor, and membrane normal service time is significantly longer than that in comparing reactor, which can attribute to accelerating precipitation of inclined-plate. In summary, integrated inclined-plate-Membrane bioreactor is a promising technology to alleviating membrane fouling and improving wastewater treatment efficiency, having good performance and bright future in application.

  11. Generation of inclined protoplanetary discs and misaligned planets through mass accretion - I. Coplanar secondary discs

    Science.gov (United States)

    Xiang-Gruess, M.; Kroupa, P.

    2017-10-01

    We study the three-dimensional (3D) evolution of a viscous protoplanetary disc that accretes gas material from a second protoplanetary disc during a close encounter in an embedded star cluster. The aim is to investigate the capability of the mass accretion scenario to generate strongly inclined gaseous discs that could later form misaligned planets. We use smoothed particle hydrodynamics to study mass transfer and disc inclination for passing stars and circumstellar discs with different masses. We explore different orbital configurations to find the parameter space that allows significant disc inclination generation. Thies et al. suggested that significant disc inclination and disc or planetary system shrinkage can generally be produced by the accretion of external gas material with a different angular momentum. We found that this condition can be fulfilled for a large range of gas mass and angular momentum. For all encounters, mass accretion from the secondary disc increases with decreasing mass of the secondary proto-star. Thus, higher disc inclinations can be attained for lower secondary stellar masses. Variations of the secondary disc's orientation relative to the orbital plane can alter the disc evolution significantly. The results taken together show that mass accretion can change the 3D disc orientation significantly resulting in strongly inclined discs. In combination with the gravitational interaction between the two star-disc systems, this scenario is relevant for explaining the formation of highly inclined discs that could later form misaligned planets.

  12. The effect of an inclined landing surface on biomechanical variables during a jumping task.

    Science.gov (United States)

    Hagins, Marshall; Pappas, Evangelos; Kremenic, Ian; Orishimo, Karl F; Rundle, Andrew

    2007-11-01

    Professional dancers sustain a high number of injuries. Epidemiological studies have suggested that performing on inclined "raked" stages increases the likelihood of injury. However, no studies have examined if biomechanical differences exist between inclined and flat surfaces during functional tasks, such as landing from a jump. Such differences may provide a biomechanical rationale for differences in injury risk for raked stages. Eight professional dancers performed drop jumps from a 40cm platform on flat and inclined surfaces while forces, lower extremity kinematics, and electromyographic activity were collected in a controlled laboratory environment. Dancers landed on the laterally inclined surface with significantly higher knee valgus (4 degrees ), peak knee flexion (9 degrees ), and medial-lateral ground reaction force (GRF) (13.4% body weight) compared to the flat condition. The posterior GRF was higher in the anterior inclined condition compared to the flat condition. In the anterior inclined condition, subjects landed with 1.4 degrees higher knee valgus, 4 degrees more plantarflexion at initial contact, and 3 degrees less dorsiflexion at the end of landing. Biomechanical variables that have been suggested to contribute to injury in previous studies are increased in the inclined floor conditions. These findings provide a preliminary biomechanical rationale for differences in injury rates found in observational studies of raked stages.

  13. Effects of an inclined walking surface and balance abilities on spatiotemporal gait parameters of older adults.

    Science.gov (United States)

    Ferraro, Richard A; Pinto-Zipp, Genevieve; Simpkins, Susan; Clark, MaryAnn

    2013-01-01

    To date, few studies have investigated how walking patterns on inclines change in healthy older adults. The purpose of the study was to examine the effects of an inclined walking surface and balance abilities on various spatiotemporal gait parameters of healthy older adults. Seventy-eight self-reported independent community ambulators (mean age, 77.8 years; SD, 4.8) participated in this study. After completing the Berg Balance Scale and Dynamic Gait Index (DGI), all participants were asked to walk on the GaitRite on level and inclined surfaces (10° slope). Dependent t tests were used to determine statistical significance between level and inclined surfaces for cadence, step length, velocity, and gait stability ratio (GSR). GSR is a measure of the degree of adaptation an individual makes to increase stability during gait derived from a ratio of cadence/velocity. A 2 2 analysis of variance was performed to determine differences in means among the higher-risk participants (as determined by the Berg Balance Scale and Dynamic Gait Index) comparing their level and incline walking patterns. The level of significance was set at P 0.05. During incline walking a significant decrease occurred in mean step length, 63.1(8.8) cm, P 0.001, mean cadence, 111.6 (8.9) step/min, P 0.01 and mean normalized velocity, 1.4 (0.23), P 0.001. However, mean GSR increased on inclines, 1.62 (0.22) steps/m, P 0.004. Main effects were evident for both walking surface and fall risk for all gait parameters tested. Healthy older adults adopt a more stable gait pattern on inclines decreasing velocity and spending more time in the double support despite the increased physiological demands to perform this task. Clear changes were evident between level and incline surfaces regardless of fall risk as defined by 2 different objective balance measures [corrected].

  14. Comparison of the buccolingual inclination in alveolar bone and tooth using dental CBCT

    International Nuclear Information System (INIS)

    Kim, Sung Eun; Kim, Jin Soo; Kim, Jae Duk

    2008-01-01

    It is important to determine the bucco-lingual inclination of implants on radiographs before the implant surgery. The purpose of this study was to compare the buccolingual inclination in alveolar bone and the tooth with dental cone beam CT and to prepare the standard for the buccolingual inclination of implant. Axial, panoramic, and buccolingually sectioned images of 80 implant cases with stent including straight marker using CB Mercuray TM (Hitachi, Japan) were evaluated. The comparison of the buccolingual inclination of remained alveolar bone with the tooth and the marker on buccolingually sectioned views was performed statistically. The average buccolingual inclination of remained alveolar bone and tooth was 82.8 ± 4.6 .deg. C and 85.8 ± 4.7 .deg. C (p 0.05, r=0.12) at the 2nd premolar area in upper jaw. The average buccolingual inclination of remained alveolar bone and tooth was 81.3 ± 8.3 .deg. C and 87.5 ± 6.3 .deg. C (p>0.05, r=0.85) at the lower 2nd premolar area and 94.3 ± 6.6 .deg. C and 93.3 ± 7.2 .deg. C respectively (p>0.05, r=0.91) at the 1st molar area in lower jaw. The inclinations of markers were very different from those of remained bone at the most of areas except the upper 2nd premolar area (r=0.79). We recommend dental CBCT analysis for determining the buccolingual inclination of dental implant, because of significant difference, in average, between the buccolingual inclination of remained alveolar bone and tooth.

  15. Non-Surgical Retreatment of Maxillary Lateral Incisor with Unusual Anatomy: A Case Report and Mini Review

    Science.gov (United States)

    Shubbar, Ashraf; Bolhari, Behnam; Fakhari, Nooshin; Alemi, Parvin; Nosrat, Ali

    2017-01-01

    Knowledge about internal anatomy plays a crucial role in the success of the root canal treatment. Many studies on internal anatomy have repeatedly reported that maxillary lateral incisors have only one canal. The primary aim of this article was to describe successful non-surgical retreatment of a permanent maxillary lateral incisor with two root canals and open apices. The treatment was carried out using dental operating microscope and the canals were obturated with mineral trioxide aggregate (MTA) as an apical plug. A review of literature was also conducted to evaluate the anatomical variations of maxillary lateral incisors. PMID:28808470

  16. A Rare Bilateral Presentation of Multiple Dens Invaginatus, Shovel-Shaped Incisor and Talon Cusp With Mesiodens.

    Science.gov (United States)

    Hegde, S; Jain, M; Shubha, A B

    2014-01-01

    The aim of this paper is to describe a unique and unusual case of concomitant appearance of morphological dental anomalies in the maxillary anterior region, along with its management in a patient with no systemic abnormality. This case report describes the clinical and radiographic features of talon cusp, dens invaginatus, shovel-shaped incisors and a supernumerary tooth occurring in a single patient, which is a rare presentation. All 4 permanent maxillary incisors had dens invaginatus, the permanent maxillary canines showed the presence of talon cusps, the permanent maxillary central incisors were shovel-shaped and an erupted mesiodens was also observed. Treatment included restorative, surgical and orthodontic approaches.

  17. Natural Convection in an Inclined Porous Cavity with Spatial Sidewall Temperature Variations

    Directory of Open Access Journals (Sweden)

    M. S. Selamat

    2012-01-01

    Full Text Available The natural convection in an inclined porous square cavity is investigated numerically. The left wall is assumed to have spatial sinusoidal temperature variations about a constant mean value, while the right wall is cooled. The horizontal walls are considered adiabatic. A finite difference method is used to solve numerically the nondimensional governing equations. The effects of the inclination angle of the cavity, the amplitude and wave numbers of the heated sidewall temperature variation on the natural convection in the cavity are studied. The maximum average Nusselt number occurs at different wave number. It also found that the inclination could influence the Nusselt number.

  18. Effect of wall inclination on natural convection in a porous trapezoidal cavity

    Science.gov (United States)

    Cheong, H. T.; Sivasankaran, S.; Siri, Z.

    2014-07-01

    The present study investigates numerically the effect of wall inclination of a trapezoidal cavity on natural convective flow and heat transfer. The cavity is filled with porous medium. Sinusoidal temperature is applied on the inclined wall and the opposite wall is maintained at a constant temperature. The top and bottom walls are adiabatic. The Darcy model is adopted for porous medium. The governing equations are solved using the finite difference method with various values of wall inclination and Rayleigh number. The heat transfer of the square cavity is found to be higher than that of trapezoidal and triangular cavities.

  19. The metabolic cost of walking on an incline in the Peacock (Pavo cristatus)

    OpenAIRE

    Wilkinson, Holly; Thavarajah, Nathan; Codd, Jonathan

    2015-01-01

    Altering speed and moving on a gradient can affect an animal’s posture and gait, which in turn can change the energetic requirements of terrestrial locomotion. Here, the energetic and kinematic effects of locomoting on an incline were investigated in the Indian peacock, Pavo cristatus. The mass-specific metabolic rate of the Indian peacock was elevated on an incline, but this change was not dependent on the angle ascended and the cost of lifting remained similar between the two inclines (+5 a...

  20. The Effect of the Angle of Inclination on the Efficiency in a Medium-Temperature Flat Plate Solar Collector

    Directory of Open Access Journals (Sweden)

    Orlando Montoya-Marquez

    2017-01-01

    Full Text Available In this experimental work, the effects of the inclination angle β and the (Ti − Ta/G on the efficiency and the UL-value were investigated on a medium-temperature flat plate solar collector. The experiments were based on steady-state energy balance, by heat flow calorimetry at indoor conditions and considering the standard American National Standard Institute/American Society of Heating Refrigerating and Air Conditioning Engineers (ANSI/ASHRAE 93-2010. The solar radiation was emulated by the Joule effect using a proportional integral derivative (PID control considering two conditions of the absorber temperature, Case 1: (To − Ti > 0, and Case 2: (To − Ti = 0. The inclination angles were 0°–90° and the (Ti − Ta/G were 0.044–0.083 m2·°C/W and 0.124–0.235 for Case 1 and Case 2, respectively. The variations of β and (Ti − Ta/G cause efficiency changes up to 0.37–0.45 (21.6% and 0.31–0.45 (45.0%, respectively, for Case 1. Also, the UL(β reached changes up to 10.1–12.0 W/m2·°C (19.2% and 8.4–12.0 W/m2·°C (41.7%, respectively, for Case 1. The most significant changes of UL(β/UL(90° vs. β were 8.0% at the horizontal position for Case 1, while for Case 2, the maximum change was 1.8% only. Therefore, the changes of the inclination angle cause significant variations of the convective flow patterns within the collector, which leads to considerable variation of the collector efficiency and its UL value.

  1. Inclination shallowing in the Eocene Linzizong sediments from Tibet: correction, possible causes and implications for reconstructing the India-Asia collision

    NARCIS (Netherlands)

    Huang, W.; Dupont-Nivet, G.; Lippert, P.C.; Hinsbergen, D.J.J. van; Hallot, E.

    2013-01-01

    A systematic bias towards low palaeomagnetic inclination recorded in clastic sediments, that is, inclination shallowing, has been recognized and studied for decades. Identification, understanding and correction of this inclination shallowing are critical for palaeogeographic

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

    Directory of Open Access Journals (Sweden)

    Anísio Bueno de Carvalho

    2012-12-01

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

  3. Beam Shear Design According to Eurocode 2 - Limitations for the Concrete Strut Inclinations

    DEFF Research Database (Denmark)

    Hagsten, Lars German; Hestbech, Lars; Fisker, Jakob

    2011-01-01

    and are presented. These beams are all designed to fail in shear and the shear reinforcement is designed for different values of the concrete strut inclinations (cot θ varies from 1.5 to 3.4). These tests indicate a clear connection between the values of the concrete strut inclinations and crack width in the SLS......The beam shear design method adopted in Eurocode 2 is based on a lower bound plastic solution. This method is combined with limitations on the concrete strut inclination, θ. These limitations are introduced to ensure acceptable crack width in the SLS. 7 full scale beams have been tested....... In cases where larger crack widths (w > 0.4 mm) can be accepted, larger values of the concrete strut inclinations can be chosen. This will lead to less shear reinforcements. The results are also compared with analytical analysis based on energy methods. At the SLS the beams are expected to be cracked...

  4. Muscular activity of lower limb muscles associated with working on inclined surfaces.

    Science.gov (United States)

    Lu, Ming-Lun; Kincl, Laurel; Lowe, Brian; Succop, Paul; Bhattacharya, Amit

    2015-01-01

    This study investigated the effects of visual cues, muscular fatigue, task performance and experience of working on inclined surfaces on activity of postural muscles in the lower limbs associated with maintaining balance on three inclined surfaces - 0°, 14° and 26°. Normalised electromyographic (NEMG) data were collected in 44 professional roofers bilaterally from the rectus femoris, biceps femoris, tibialii anterior and gastrocnemii medial muscle groups. The 50th and 95th percentile NEMG amplitudes were used as EMG variables. Results showed that inclination angle and task performance caused a significant increase in the NEMG amplitudes of all postural muscles. Visual cues were significantly associated with a decrease in the 95th percentile EMG amplitude for the right gastrocnemius medial and tibialis anterior. Fatigue was related to a significant decrease in the NEMG amplitude for the rectus femoris. Experience of working on inclined surfaces did not have a significant effect on the NEMG amplitude.

  5. Revascularization of an impacted, immature dilacerated permanent maxillary central incisor associated with odontoma and a supernumerary tooth

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2013-01-01

    Full Text Available To intentionally replant an impacted immature permanent maxillary central incisor in the mixed dentition period followed by revascularization in order to achieve apical root closure. A 9-year-old boy presented with retained maxillary left primary incisors. Radiographic evaluation revealed the presence of a supernumerary tooth and an odontoma associated with an impacted permanent maxillary left central incisor, having root dilaceration. Treatment included surgical removal of mesiodens and odontoma. The impacted dilacerated permanent central incisor was removed and intentionally replanted, followed by revascularization of pulp. During the follow-up, root end closure with narrowing of canal space was observed, patient has been asymptomatic and the tooth remains vital. Revascularization of the immature reimplanted tooth showed continued root development and thickening of the lateral dentinal walls through deposition of new hard tissue and narrowing of the canal space.

  6. Mollenhauer Aligning Auxiliary for Bodily Alignment of Blocked-out Lateral Incisors in Preadjusted Edgewise Appliance Therapy

    Directory of Open Access Journals (Sweden)

    Sreekrishnan B Nair

    2014-01-01

    Conclusion: Mollenhauer aligning auxiliary can be effectively used for the bodily alignment of lingually placed lateral incisors in preadjusted edgewise appliance therapy as an alternative to torquing with rectangular wires.

  7. [A three dimensional finite element study on stress distribution in maxillary central incisor restored with fiber post].

    Science.gov (United States)

    Kang, Cheng-rong; Wei, Su-hua; Zhang, Mei-chao; Zhang, Xin-chun

    2008-08-01

    To study the stress changes of maxillary central incisor restored with or without fiber post using three dimensional finite element method, and analysis the role of fiber post in determining the stress distribution in dentin. Three dimensional finite element models of maxillary central incisor with various remaining tooth structure were established by spiral CT, Mimics software and ANSYS software. Test samples were restored with all-ceramic crown and fiber post all-ceramic crown, respectively. The von Mises stress and maximal tensile stress of dentin were recorded. The stress level in dentin of maxillary central incisor restored with fiber post all-ceramic crown was smaller than that restored with all-ceramic crown, the stress distribution of both were similar. The apply of fiber post can reduce the stress level in dentin of maxillary central incisor and decrease the risk of tooth breakage, but not change the stress pattern.

  8. Essentiality of early diagnosis of molar incisor hypomineralization in children and review of its clinical presentation, etiology and management.

    Science.gov (United States)

    Garg, Nishita; Jain, Abhay Kumar; Saha, Sonali; Singh, Jaspal

    2012-09-01

    Molar incisor hypomineralization (MIH) is a common developmental condition resulting in enamel defects in first permanent molars and permanent incisors. It presents at eruption of these teeth. One to four molars, and often also the incisors, could be affected. Since first recognized, the condition has been puzzling and interpreted as a distinct phenomenon unlike other enamel disturbances. Early diagnosis is essential since, rapid breakdown of tooth structure may occur, giving rise to acute symptoms and complicated treatment. The purpose of this article is to review MIH and illustrate its diagnosis and clinical management in young children. How to cite this article: Garg N, Jain AK, Saha S, Singh J. Essentiality of Early Diagnosis of Molar Incisor Hypomineralization in Children and Review of its Clinical Presentation, Etiology and Management. Int J Clin Pediatr Dent 2012;5(3):190-196.

  9. Duration for Apical Barrier Formation in Necrotic Immature Permanent Incisors Treated With Calcium Hydroxide Apexification Using Ultrasonic or Hand Filing

    Directory of Open Access Journals (Sweden)

    Li-Wan Lee

    2010-08-01

    Conclusion: Ultrasonic filing with 0.2% chlorhexidine as an irrigant is effective for disinfection of the root canal and can shorten the duration for apical barrier formation in necrotic permanent incisors treated with calcium hydroxide apexification.

  10. Unusual Transalveolar and Transmuco-Gingival Root Avulsion of a Fractured Primary Central Incisor: A Case with an 8-Year Follow-Up

    Science.gov (United States)

    Ferrés-Amat, E.; Díaz-Martínez, C.; Herrera-Martínez, S.; Maura-Solivellas, I.; Ferrés-Padró, E.

    2015-01-01

    The purpose of this unique case report is to describe a very unusual dentoalveolar fracture associated with avulsion of the near-complete root. A 3-year-old male patient came for consultation after a dentoalveolar trauma with a “fragment that looks like canine” found in his mouth by his mother. This boy suffered root fracture of the upper primary central right incisor, accompanied by transalveolar and transmuco-gingival avulsion of the tooth root fragment, leaving the crown in its position in the dental arch. Clinical and radiological examinations were performed in order to follow up the case: 15 days, one month, and three months after trauma, the crown had a slight mobility without other clinical or radiological signs. After six months, the upper primary central right incisor's crown was exfoliated. Open bite due to the persistence of the pacifier habit favored the crown retention in the mouth. This case emphasizes the importance of primary diagnosis and follow-up of trauma cases. To the best of our knowledge, this kind of dental injury has not been previously described in the literature nor in the current Dental Trauma guidelines for the management of traumatic dental injuries in the primary dentition. PMID:25793129

  11. Lateral dynamic flight stability of a model hoverfly in normal and inclined stroke-plane hovering

    International Nuclear Information System (INIS)

    Xu, Na; Sun, Mao

    2014-01-01

    Many insects hover with their wings beating in a horizontal plane (‘normal hovering’), while some insects, e.g., hoverflies and dragonflies, hover with inclined stroke-planes. Here, we investigate the lateral dynamic flight stability of a hovering model hoverfly. The aerodynamic derivatives are computed using the method of computational fluid dynamics, and the equations of motion are solved by the techniques of eigenvalue and eigenvector analysis. The following is shown: The flight of the insect is unstable at normal hovering (stroke-plane angle equals 0) and the instability becomes weaker as the stroke-plane angle increases; the flight becomes stable at a relatively large stroke-plane angle (larger than about 24°). As previously shown, the instability at normal hovering is due to a positive roll-moment/side-velocity derivative produced by the ‘changing-LEV-axial-velocity’ effect. When the stroke-plane angle increases, the wings bend toward the back of the body, and the ‘changing-LEV-axial-velocity’ effect decreases; in addition, another effect, called the ‘changing-relative-velocity’ effect (the ‘lateral wind’, which is due to the side motion of the insect, changes the relative velocity of its wings), becomes increasingly stronger. This causes the roll-moment/side-velocity derivative to first decrease and then become negative, resulting in the above change in stability as a function of the stroke-plane angle. (paper)

  12. Natural Convection in an Inclined Porous Cavity with Spatial Sidewall Temperature Variations

    OpenAIRE

    Selamat, M. S.; Roslan, R.; Hashim, I.

    2012-01-01

    The natural convection in an inclined porous square cavity is investigated numerically. The left wall is assumed to have spatial sinusoidal temperature variations about a constant mean value, while the right wall is cooled. The horizontal walls are considered adiabatic. A finite difference method is used to solve numerically the nondimensional governing equations. The effects of the inclination angle of the cavity, the amplitude and wave numbers of the heated sidewall temperature variation o...

  13. The effect of speleothem surface slope on the remanent magnetic inclination

    Science.gov (United States)

    Ponte, J. M.; Font, E.; Veiga-Pires, C.; Hillaire-Marcel, C.; Ghaleb, B.

    2017-06-01

    Speleothems are of interest for high-resolution reconstruction of the Earth's magnetic field. However, little is known about the influence of speleothem morphologies on their natural remanent magnetization (NRM) record. Here we report on a high-resolution paleomagnetic study of a dome-shaped speleothem of middle Holocene age from southern Portugal, with special attention to the anisotropy of magnetic susceptibility (AMS) and anisotropy of anhysteretic remanent magnetization (AARM). To assess the potential influence of the slope of the speleothem surface on the recorded remanent magnetization, we compare magnetic directions and AMS and AARM fabrics from subhorizontal to gradually subvertical calcite growth layers collected in a transversal cross section of the speleothem. A linear correlation is observed between magnetic inclinations, calcite laminae slope, and AARM k1 inclination. The AMS fabric is mostly controlled by calcite crystals, with direction of the minimum axes (k3) perpendicular to laminae growth. Magnetic inclinations recorded in inclined and vertical calcite growth layers are underestimated when compared to a global paleosecular variation (PSV) model. After extrapolating magnetic inclinations to the horizontal, the corrected data better fit the PSV model but are still lower than the predicted magnetic inclinations, suggesting that inclination shallowing affects the entire speleothem. We suggest that speleothem morphology exerts a critical role on the magnetic inclination recording, which is controlled by the Earth's magnetic field but also influenced by particle rolling along the sloping surfaces. These observations open new avenues for reconstructing high-resolution paleomagnetic secular variation records from speleothems and provide new insights into their NRM acquisition mechanisms.

  14. Prevalence of molar incisor hypomineralization in school children aged 8-12 years in Chennai

    Directory of Open Access Journals (Sweden)

    Savitha Deepthi Yannam

    2016-01-01

    Full Text Available Objective: To investigate the prevalence and severity of molar incisor hypomineralization (MIH. Materials and Methods: A sample of 2,864 students aged 8-12 years were selected from government and private schools in Chennai. MIH was diagnosed clinically based on the diagnostic criteria established by the European Academy of Pediatric Dentistry (EAPD 2003. Results: A total of 277 children (9.7% had MIH. There was statistically significant difference in prevalence related to age but there was no statistical difference in prevalence with respect to gender. Conclusion: Prevalence of MIH was 9.7% in the child population residing in Chennai. Males and females were equally affected. The rate of occurrence and severity of MIH are more in the right mandibular first molar. The severity of MIH is more in molars compared to incisors (P < 0.001 and is more in government schools compared to private schools (P = 0.002.

  15. Prevalence of molar incisor hypomineralization in school children aged 8-12 years in Chennai.

    Science.gov (United States)

    Yannam, Savitha Deepthi; Amarlal, Deepti; Rekha, Chamarthi Vishnu

    2016-01-01

    To investigate the prevalence and severity of molar incisor hypomineralization (MIH). A sample of 2,864 students aged 8-12 years were selected from government and private schools in Chennai. MIH was diagnosed clinically based on the diagnostic criteria established by the European Academy of Pediatric Dentistry (EAPD) 2003. A total of 277 children (9.7%) had MIH. There was statistically significant difference in prevalence related to age but there was no statistical difference in prevalence with respect to gender. Prevalence of MIH was 9.7% in the child population residing in Chennai. Males and females were equally affected. The rate of occurrence and severity of MIH are more in the right mandibular first molar. The severity of MIH is more in molars compared to incisors (P < 0.001) and is more in government schools compared to private schools (P = 0.002).

  16. A Case of Successful Retreatment of a Maxillary Lateral Incisor with a Supernumerary Root

    Directory of Open Access Journals (Sweden)

    Mohsen Aminsobhani

    2016-03-01

    Full Text Available Knowledge about the morphology of the root canal system is a pre-requisite for achieving a successful outcome in root canal treatment. In this report, a patient with a maxillary lateral incisor which had previously undergone orthograde endodontic retreatment for two times is discussed. The tooth had been misdiagnosed with a palatal groove or a root fracture, its prognosis had been determined to be poor and extraction was advised by a practitioner. During our evaluation, an unrecognized supernumerary root and root canal were detected and the tooth was maintained successfully with orthograde endodontic retreatment. The use of cone beam computed tomography (CBCT and magnification were of significance in the treatment process of this case.Key words: Tooth, Supernumerary; Incisor; Maxilla; Root Canal Therapy

  17. Molar incisor hypomineralization: considerations about treatment in a controlled longitudinal case.

    Science.gov (United States)

    de Oliveira, Daniela Cristina; Favretto, Carla Oliveira; Cunha, Robson Frederico

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Daniela Cristina de Oliveira

    2015-01-01

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

  19. Dental caries, malocclusion and fractured incisors in children from a pastoral community in Kenya.

    Science.gov (United States)

    Ng'ang'a, P M; Karongo, P K; Chindia, M L; Valderhaug, J

    1993-03-01

    The prevalence of dental caries, malocclusion and fractured incisors was investigated in 245 children from a pastoral community in Kenya. Forty-eight per cent of them were found to be caries-free. The overall mean DMFT was 1.9 (s.d. 2.7). Among those with caries, the mean DMFT was 3.0 (s.d. 2.0). Fifty-eight per cent of the children had malocclusion. Overall, 84% of the sample had Angle's Class I, 11% Class II and 5% Class III molar relation. The prevalence of fractured incisors was 15%. Most of the fractures were in the maxilla and involved enamel only. Minimal treatment had been carried out on the children.

  20. Accelerated decompensation of mandibular incisors in surgical skeletal class III patients by using augmented corticotomy: a preliminary study.

    Science.gov (United States)

    Ahn, Hyo-Won; Lee, Dong-Yeol; Park, Young-Guk; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald

    2012-08-01

    Our objectives were to evaluate the amount of decompensation of the mandibular incisors and the change of periodontal support around them after corticotomy with bone augmentation before orthognathic surgery. Before orthognathic surgery for 15 skeletal Class III patients, orthodontic treatment was combined with corticotomy and bone augmentation labially to the anterior mandibular roots. Lateral cephalograms were taken before orthodontic treatment and before surgery (completion of preoperative orthodontic treatment). The amounts of mandibular incisor proclination, alveolar bone thickness, and periodontal support (gingival margin levels and augmentation pattern) were evaluated. Significant proclination of the mandibular incisors was shown after decompensation (P <0.001; incisor mandibular plane angle, 10.45°; incisor symphyseal plane angle, 10.74°). The incisor edge moved labially by 3.47 mm. The alveolar bone thickness increased by 1.56 mm at the root apex and 1.98 mm at the level of B-point (P <0.001). There was no gingival recession irrespective of the degree of proclination of the mandibular incisiors. Two types of bone augmentation pattern were evident. One was characterized by alveolar bone proclination proportional to the labial tipping of the mandibular incisors. Buccal alveolar bone at the cervical area was well maintained (60%, 9 subjects). The other showed greater increases in alveolar thickness at B-point than at the cervical area (40%, 6 subjects). The augmented corticotomy provided effective decompensation of the mandibular incisors in skeletal Class III patients while maintaining labial bone thickness and with no periodontal side effects. This technique reduces or eliminates the risk of moving the roots through the labial plate during decompensation with the associated risk of gingival recession. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.