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1.
Am J Orthod Dentofacial Orthop ; 164(5): 612-613, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37914435
2.
J Orthod ; 50(4): 439-448, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37148164

RESUMEN

INTRODUCTION: Artificial intelligence (AI) technology has transformed the way healthcare functions in the present scenario. In orthodontics, expert systems and machine learning have aided clinicians in making complex, multifactorial decisions. One such scenario is an extraction decision in a borderline case. OBJECTIVE: The present in silico study was planned with the intention of building an AI model for extraction decisions in borderline orthodontic cases. DESIGN: An observational analytical study. SETTING: Department of Orthodontics, Hitkarini Dental College and Hospital, Madhya Pradesh Medical University, Jabalpur, India. METHODS: An artificial neural network (ANN) model for extraction or non-extraction decisions in borderline orthodontic cases was constructed based on a supervised learning algorithm using the Python (version 3.9) Sci-Kit Learn library and feed-forward backpropagation method. Based on 40 borderline orthodontic cases, 20 experienced clinicians were asked to recommend extraction or non-extraction treatment. The decision of the orthodontist and the diagnostic records, including the selected extraoral and intra-oral features, model analysis and cephalometric analysis parameters, constituted the training dataset of AI. The built-in model was then tested using a testing dataset of 20 borderline cases. After running the model on the testing dataset, the accuracy, F1 score, precision and recall were calculated. RESULTS: The present AI model showed an accuracy of 97.97% for extraction and non-extraction decision-making. The receiver operating curve (ROC) and cumulative accuracy profile showed a near-perfect model with precision, recall and F1 values of 0.80, 0.84 and 0.82 for non-extraction decisions and 0.90, 0.87 and 0.88 for extraction decisions. LIMITATION: As the present study was preliminary in nature, the dataset included was too small and population-specific. CONCLUSION: The present AI model gave accurate results in decision-making capabilities related to extraction and non-extraction treatment modalities in borderline orthodontic cases of the present population.


Asunto(s)
Inteligencia Artificial , Ortodoncia , Humanos , Algoritmos , Redes Neurales de la Computación , Ortodoncistas
3.
Am J Orthod Dentofacial Orthop ; 164(2): 253-264, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36959013

RESUMEN

INTRODUCTION: Treating a Class III malocclusion is often challenging for orthodontists. Bone-anchored maxillary protraction (BAMP) is known for achieving a significant maxillary protraction. The study aimed to evaluate the stress distribution and displacement of craniofacial bones as a reaction to the forces of BAMP, along with rapid maxillary expander and the posterior bite plane, in growing patients with skeletal Class III malocclusion using a finite element method. METHODS: An finite element model was constructed from the spiral computed tomographic images of a skull from an 11-year-old growing patient with skeletal Class III malocclusion along with BAMP, rapid maxillary expander, and the posterior bite plane. The created model had 105,189 nodes and 481,066 elements. After assigning the appropriate material properties and the boundary condition, 800 g of transverse force per side and a Class III intraoral elastic 250 g of force per side were applied to the model, and after the postprocessing, the results were obtained in the form of color bands. RESULTS: The maxilla and the attached structures were displaced and expanded transversely. The maxilla was displaced anteriorly by 0.692 mm, and the mandible was displaced backward by 0.204 mm in the sagittal direction. The anterior region of the maxilla and mandible, dentition, and nasal bone were rotated counterclockwise. Displacement in an upward direction was greatest at the symphysis region of the mandible. The stresses experienced by most of the bones were tensile, with the maxilla and maxillary dentition experiencing the maximum. CONCLUSIONS: Favorable changes were appreciated with maxillary forward and mandibular backward displacement, with appreciable tensile stresses in all the bones.


Asunto(s)
Maloclusión de Angle Clase III , Maxilar , Humanos , Niño , Maxilar/diagnóstico por imagen , Análisis de Elementos Finitos , Técnica de Expansión Palatina , Cráneo , Maloclusión de Angle Clase III/diagnóstico por imagen , Maloclusión de Angle Clase III/terapia , Cefalometría/métodos
4.
Arch Oral Biol ; 146: 105606, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36577312

RESUMEN

OBJECTIVES: cortical bone thickness confines the position of teeth and thus can be a limiting factor for orthodontic tooth movement. The study is aimed to correlate the cortical bone thickness of the maxilla and mandible with that of different face types, viz; dolichofacial, brachyfacial, and mesofacial. METHODS: Forty CT scans were analysed for the face types and were grouped into dolichofacial (13), brachyfacial (13) and mesofacial (14) face types. The scans were measured for the right and left side buccal and lingual cortical bone thickness at the central incisor, first and second molar regions on both the maxilla and mandible. Other parameters like basal cortical bone thickness, height, and width of cortical bone were also measured. To determine the correlation and difference between the different parameters, the obtained data was subjected to the correlation coefficient, t test, and ANOVA statistical analysis. RESULTS: Maxillary buccal cortical bone thickness of central incisors was found to be highly correlated to facial index with a correlation coefficient of - 0.833 * *. Mandibular buccal bone thickness correlated with face type and cortical bone thickness at the central incisor, first, and second molars by-0.531 * *, - 0.474 * *, and - 0.589 * *, respectively. There was a significant difference between the right and left side cortical bone thickness (p < 0.05) and also for all the parameters amongst the different face types (p < 0.05). CONCLUSION: There exists a definite correlation between the face type and the certain anatomical measurements of cortical bone morphology. Dolichofacial face types show thin buccal cortical bone, which implies the limitation of orthodontic tooth movement in these types of individuals.


Asunto(s)
Maxilar , Diente , Humanos , Maxilar/diagnóstico por imagen , Maxilar/anatomía & histología , Mandíbula/diagnóstico por imagen , Mandíbula/anatomía & histología , Tomografía Computarizada por Rayos X , Hueso Cortical/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos
5.
Int Orthod ; 17(3): 451-460, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31302004

RESUMEN

OBJECTIVE: To evaluate and compare the stress and displacement pattern between conventional and micro-implant supported retraction in lingual orthodontic system. MATERIALS AND METHODS: A finite element model of the maxilla, teeth, periodontal ligament, lingual-orthodontic appliance and a micro-implant complex was constructed using ANSYS 12.1 software. Two sizes of micro-implants, 6mm and 8mm, were constructed producing a simulated model of 99,190 nodes and 32,4364 elements. A retraction force of 200g was applied from an anterior retraction hook to the molar tube in the conventional model and from the micro-implants in the implant supported model. The initial displacement and stress patterns in the X-Y-Z axes were obtained using Hyper-view software. RESULTS: The maximum von Mises stresses in the 6mm, 8mm and conventional model were 22.164 Megapascals (MPa), 28.603MPa and 16.491MPa respectively. The bucco-lingual displacement of the maxillary anteriors was greater in the 8mm implant model with 23×10-3mm lingual displacement observed. The least lingual displacement of 11×10-3mm was noted for the conventional model while a slightly higher moderate reading of 15×10-3mm was seen in the 6mm micro-implant supported model. The maximum displacement of the periodontal ligament was noted in the 8mm micro-implant model. CONCLUSION: Within the limitations of this research, the 8mm micro-implant model displayed high initial stresses and greater initial displacement of the anterior teeth in the X-Y-Z coordinates in comparison to conventional retraction method.


Asunto(s)
Implantes Dentales , Dentición , Análisis de Elementos Finitos , Maxilar , Métodos de Anclaje en Ortodoncia/instrumentación , Aparatos Ortodóncicos , Estrés Mecánico , Técnicas de Movimiento Dental/métodos , Humanos , Modelos Dentales , Métodos de Anclaje en Ortodoncia/métodos , Diseño de Aparato Ortodóncico , Soportes Ortodóncicos , Alambres para Ortodoncia , Ligamento Periodontal , Acero Inoxidable , Corona del Diente , Técnicas de Movimiento Dental/instrumentación
6.
Int Orthod ; 16(1): 31-41, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29478935

RESUMEN

AIM: The study was aimed to assess the effect of different pH and immersion time on the amount of nickel release from simulated orthodontic appliance of 3M Unitek company. MATERIAL AND METHOD: Nickel ion release was evaluated after subjecting the brackets to the simulated artificial oral environment. In this study, 90 stainless steel brackets of 3M Unitek Company were tested by immersing them in artificial saliva of pH 4.2, pH 6.5 and pH 7.6 for a time interval of 1hour, 1 week and 1 month (T1 - 1h, T2 - 7 days, T3 - 30 days) respectively. The data was subjected for the one-way ANOVA and the post-hoc test for the statistical comparison. RESULTS: Means of 2.99±0.77, 9.53±4.26 and 12.65±2 .52 ppb (parts per billion by volume) of nickel were released for 4.2 pH at a time interval of 1hour, 7 days and 1 month respectively. Means of 5.37±2.26, 10.94±1.51 and 16.92±1.69 ppb of nickel were released for 6.5 pH at a time interval of 1hour, 7 days and 1 month respectively. A mean of 2.13±0.92, 0.74±0.54 and 18.83±1.02 ppb of nickel was released for 7.6 pH at a time interval of 1 hr, 7 days and 1 month respectively. CONCLUSION: pH of the artificial saliva significantly affected the amount of nickel release. Acidic pH was found to increase the amount of nickel release in the artificial saliva. Time duration of bracket immersion significantly affected the amount of nickel release.


Asunto(s)
Ensayo de Materiales , Níquel/química , Soportes Ortodóncicos , Humanos , Concentración de Iones de Hidrógeno , Alambres para Ortodoncia , Saliva Artificial
7.
Braz. j. oral sci ; 16: e17015, jan.-dez. 2017. tab
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-884111

RESUMEN

Objective: Comparison of the prevalence of usage of tobacco products and its effect on the periodontal health parameters of the mining laborers and the general population of Udaipur city, India. Materials and methods: the cross sectional study was performed on the sample of 980 adults including 500 mining employees and 480 subjects from the general population. The presence or absence of the tobacco products usage was noted. The ADA type III examination using the community periodontal probe was done. The data obtained was subjected to chi-square and Cramer' v statistical analysis. Results: 79.40% of the mining-employees and 61.67% of the general population used different tobacco products, the difference noted was statistically significant (p=0.000). The most common periodontal condition amongst the mining employees and the general population was the presence of calculus (39% and 35.63% respectively) followed by the 4-5mm periodontal probing depth (29.20% and 26.04% respectively). The difference spotted was significant (p=0.018). There was statistically significant difference between the tobacco users and non- users for the different periodontal conditions (p=0.000). Conclusion: the tobacco product usage was high in mining employees group. There was a positive correlation between the usage of tobacco products and the periodontal health parameters (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Minería , Salud Bucal , Índice Periodontal , Periodoncio , Nicotiana
8.
Prog Orthod ; 18(1): 3, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28092094

RESUMEN

BACKGROUND: The study aimed to evaluate and compare the stress distribution and 3-dimensional displacements along the craniofacial sutures in between the Rapid maxillary Expansion (RME) and Implant supported RME (I-RME). METHODS: Finite element model of the skull and the implants were created using ANSYS software. The finite element model thus built composed of 537692 elements and 115694 nodes in RME model & 543078 elements and 117948 nodes with implants model. The forces were applied on the palatal surface of the posterior teeth to cause 5mm of transverse displacement on either side of the palatal halves, making it a total of 10mm. The stresses and the displacement values were obtained and interpreted. RESULTS: Varying pattern of stress and the displacements with both positive and negative values were seen. The maximum displacement was seen in the case of plain RME model and that too at Pterygomaxillary suture and Mid-palatal suture in descending order. In the case of I-RME maximum displacement was seen at Zygomaticomaxillary suture followed by Pterygomaxillary suture. The displacements produced in all the three planes of space for the plain RME model were greater in comparison to the Implant Supported RME model. And the stresses remained high for all the sutures in case of an I-RME. CONCLUSIONS: There is a definite difference in the stress and the displacement pattern produced by RME and I-RME model and each can be used according to the need of the patient. The stresses generated in case of conventional RME were considerably less than that of the I-RME for all the sutures.


Asunto(s)
Implantes Dentales , Análisis del Estrés Dental , Técnica de Expansión Palatina , Suturas Craneales/patología , Suturas Craneales/fisiopatología , Implantes Dentales/efectos adversos , Análisis del Estrés Dental/métodos , Análisis de Elementos Finitos , Humanos , Maloclusión de Angle Clase III/terapia , Técnica de Expansión Palatina/efectos adversos , Cráneo/patología , Cráneo/fisiopatología , Estrés Mecánico
9.
Turk J Orthod ; 30(3): 73-77, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30112496

RESUMEN

OBJECTIVE: The study aimed to estimate the need of orthodontic treatment in 7-16-year-old school children in Udaipur city, India. METHODS: This cross sectional study enrolled 1029 subjects (661 males and 368 females) belonging to Udaipur city, Rajasthan, India. Subjects who had not undergone orthodontic treatment were randomly selected. The need for orthodontic treatment was assessed using the Dental Health Component of the Index of Orthodontic Treatment Need (IOTN) by the same calibrated examiner. Collected data were quantitatively analyzed, and the difference pertaining to prevalence between males and females was measured using the chi-square test. RESULTS: A Grade 1 IOTN score was observed in 48.4% of the population. Grade 2 was observed in 22.9% of the population. A significant difference was noted for the prevalence of Grades 1, 2, and 3 between male and female children, with male children showing greater prevalence of malocclusion grades. Grades 4 and 5, which were noted less frequently, did not show a significant difference with respect to sex. CONCLUSION: A higher percentage of the sample required moderate orthodontic treatment. This necessitates proper education and motivation to undergo orthodontic treatment.

10.
J Clin Diagn Res ; 10(9): ZC80-ZC84, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27790586

RESUMEN

INTRODUCTION: The lateral cephalometric skeletal discrepancy indicators play a major role in diagnosing and preparing a case for orthognathic surgeries and the dentofacial corrections. AIM: The study was aimed to check the reliability and the predictability of different anterio-posterior skeletal discrepancy indicators in different age groups and to derive the most reliable indicator for the orthodontic diagnosis. MATERIALS AND METHODS: A cross-sectional study was conducted on a sample of 100 subjects including 29 adolescent (15 males and 14 females) and 71 adult (41 males and 30 females) subjects with the mean age of 19.05 ± 5.78 years. All the subjects had Angle's Class I molar relationship. The lateral cephalograms of the sample were taken under the standard setting and hand tracing of the cephalometric radiographs using a sharp 4H pencil were made on acetate tracing paper. The anterio-posterior cephalometric indicators like ß-angle, Wits appraisal (mm), Sella- Nasion plane to Point A and Point B distance (SN-AB mm) and Maxillo-Mandibular plane angle bisector to Point A and Point B distance (MM-AB mm) were measured. Intra-examiner reliability of tracings was evaluated using Intra Class Correlation (ICC) test. Mann Whitney U-test was applied for comparison of parameters between different malocclusion groups. Concurrent validity of various parameters was calculated using Cohen's kappa. A p-value <0.05 was considered statistically significant. RESULTS: The comparison of intra-examiner reliability of tracings in Angle's Class I adolescent group showed, MM-AB to have an almost perfect agreement followed by Wits. Intra-examiner reliability of tracings in Angle's Class I adult group showed moderate agreement for Wits and MM-AB showed almost perfect agreement and all the parameters showed statistically significant ICC. Comparison of parameters between adolescent and adult, Angle's Class I malocclusion group showed significant difference between adolescent and adult group for the Wits and SN-AB parameter. CONCLUSION: The final outcome of the present study revealed that, the MM-AB is highly reliable in the reproducibility and also highly valid parameter for checking antero-posterior discrepancies and ANB angle was least reliable for diagnosing the antero-posterior skeletal discrepancies.

11.
Acta Inform Med ; 23(5): 285-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26635436

RESUMEN

OBJECTIVES: The study was aimed to evaluate the pharyngeal airway linear measurements of untreated skeletal class II subjects with normal facial vertical pattern in prognathic maxilla with orthognathic mandible and orthognathic maxilla with retrognathic mandible. MATERIALS AND METHOD: the sample comprised of lateral Cephalograms of two groups (30 each) of class II malocclusion variants. Group 1 comprised of class II malocclusion with prognathic maxilla and orthognathic mandible, whereas group 2 comprised of class II malocclusion with orthognathic maxilla and retrognathic mandible. Each group was traced for the linear measurements of the pharyngeal airway like the oropharynx, nasopharynx and soft palate. The obtained data was subjected to independent t test and the Mann Whitney test to check the difference between the two groups and within the groups respectively. RESULTS: there was significant difference between all the linear measurements at the soft palate region and the distance between the tip of soft palate to its counter point on the pharyngeal wall in oropharynx region (p-ppm). CONCLUSION: the pharyngeal airway for class II malocclusion with various combination in an average growth pattern adult showed significant difference. The present results suggested, that the pharyngeal airway space might be the etiological factor for different sagittal growth pattern of the jaws and probable usage of different growth modification appliance can influence the pharyngeal airway.

12.
Dental Press J Orthod ; 20(2): 76-82, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25992991

RESUMEN

OBJECTIVE: This article aims to analyze the difference in stresses generated in the bracket-cement-tooth system by means of a peel load in single and double-mesh bracket bases using a three-dimensional finite element computer model. MATERIAL AND METHODS: A three-dimensional finite element model of the bracket-cement-tooth system was constructed and consisted of 40,536 bonds and 49,201 finite elements using a commercial mesh generating programmer (ANSYS 7.0). Both single and double-mesh bracket bases were modified by varying the diameter from 100-400 µm progressively, and the spacing between the mesh wires was kept at 300 µm for each diameter of wire. A peel load was applied on the model to study the stresses generated in different layers. RESULTS: In case of double-mesh bracket base, there was reduction in stress generation at the enamel in comparison to single-mesh bracket base. There was no difference in stress generated at the bracket layer between single and double-mesh bracket bases. At the impregnated wire mesh (IWM), layer stresses increased as the wire diameter of the mesh increased. CONCLUSION: Results show that bracket design modification can improve bonding abilities and simultaneously reduce enamel damage while debonding. These facts may be used in bringing about the new innovative bracket designs for clinical use.


Asunto(s)
Recubrimiento Dental Adhesivo , Análisis de Elementos Finitos , Diseño de Aparato Ortodóncico , Soportes Ortodóncicos , Diente Premolar/anatomía & histología , Diseño Asistido por Computadora , Cementos Dentales/química , Esmalte Dental/anatomía & histología , Humanos , Imagenología Tridimensional/métodos , Estrés Mecánico , Tomografía Computarizada por Rayos X/métodos , Interfaz Usuario-Computador
13.
Acta Inform Med ; 23(1): 44-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25870491

RESUMEN

OBJECTIVE: The aim of the study is to detect gender-wise difference in the skeletal asymmetry in the esthetically pleasing faces. MATERIALS AND METHODS: a cross sectional study was conducted on 25 females and 25 males of age 18 -25 years using the posterior-anterior cephalograms. The selected part of grummon's frontal analysis for analyzing the vertical skeletal asymmetries, mandibular morphology, transverse asymmetry and mandibular deviation was used. The obtained data was subjected to independent student's't' test for comparing the difference between males and females. RESULTS: there was statistically significant difference between the males and females for the measurements like Gonion-Menton length for the mandibular morphology and for the transverse parameters like zygomatico frontal suture length, jular length and antegonial notch length. There was no significant difference for the sidedness of asymmetry for the males and females. CONCLUSION: frontal facial asymmetry showed sexual dimorphism with males showing greater asymmetric values than the females. The asymmetry showed right sided prominence for both the males and females. This knowledge can be utilized for planning facial reconstruction and remodeling surgeries.

14.
Dental press j. orthod. (Impr.) ; 20(2): 76-82, Mar-Apr/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-745850

RESUMEN

OBJECTIVE: This article aims to analyze the difference in stresses generated in the bracket-cement-tooth system by means of a peel load in single and double-mesh bracket bases using a three-dimensional finite element computer model. MATERIAL AND METHODS: A three-dimensional finite element model of the bracket-cement-tooth system was constructed and consisted of 40,536 bonds and 49,201 finite elements using a commercial mesh generating programmer (ANSYS 7.0). Both single and double-mesh bracket bases were modified by varying the diameter from 100-400 µm progressively, and the spacing between the mesh wires was kept at 300 µm for each diameter of wire. A peel load was applied on the model to study the stresses generated in different layers. RESULTS: In case of double-mesh bracket base, there was reduction in stress generation at the enamel in comparison to single-mesh bracket base. There was no difference in stress generated at the bracket layer between single and double-mesh bracket bases. At the impregnated wire mesh (IWM), layer stresses increased as the wire diameter of the mesh increased. CONCLUSION: Results show that bracket design modification can improve bonding abilities and simultaneously reduce enamel damage while debonding. These facts may be used in bringing about the new innovative bracket designs for clinical use. .


OBJETIVO: o objetivo do presente artigo é analisar a diferença entre as tensões geradas na interface braquete-cemento-dente por meio do teste peel load em bases de braquete de malha simples e dupla e do método de elementos finitos tridimensional. MÉTODOS: foi construído um modelo de elementos finitos do sistema composto pela interface braquete-cemento-dente. Esse modelo consistiu de 40.536 nós e 49.201 elementos finitos. A análise foi feita com a ajuda do programa ANSYS 7.0. Tanto a base de braquete de malha única quanto a de malha dupla sofreram modificações no diâmetro, que variou de 100 a 400µm, progressivamente. O espaço entre os fios das malhas foi mantido a 300µm para o diâmetro de cada fio. O teste peel load foi aplicado ao modelo para investigar as tensões geradas nas diferentes camadas. RESULTADOS: quando comparadas às bases de braquetes de malha simples, as bases de braquetes de malha dupla geraram menos tensão no esmalte dentário. Não foram detectadas diferenças entre as tensões geradas na superfície dos braquetes com bases de malha simples e dupla. Na malha de fios impregnados (MFI), houve um aumento na tensão com o aumento do diâmetro dos fios que compõem a malha. CONCLUSÃO: os resultados revelam que as modificações no desenho do braquete podem aumentar a colagem e, ao mesmo tempo, minimizar os danos causados no esmalte durante o processo de descolagem. Esses fatos podem ser utilizados no desenvolvimento de desenhos de braquetes inovadores, destinados à utilização clínica. .


Asunto(s)
Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Colorrectales/prevención & control , Detección Precoz del Cáncer/métodos , Sistemas Recordatorios , Montana
15.
Int J Orthod Milwaukee ; 25(1): 31-3, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24812739

RESUMEN

Segmental T loop is the most popular frictionless mechanics so far. This biomechanically sound system was designed for the Burstone's canine bracket, which can be extra inventory for the clinicians who want to practice the segmental T loop routinely. The present manuscript provides the alternate to Burstones canine bracket for the retraction of the anterior segment.


Asunto(s)
Diseño de Aparato Ortodóncico , Alambres para Ortodoncia , Técnicas de Movimiento Dental/instrumentación , Fenómenos Biomecánicos , Diente Canino/patología , Femenino , Humanos , Maloclusión Clase II de Angle/terapia , Soportes Ortodóncicos , Cierre del Espacio Ortodóncico/instrumentación , Adulto Joven
16.
Oral Health Dent Manag ; 12(1): 17-23, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23474577

RESUMEN

AIMS: The aims of the study were: to assess the prevalence of traumatic injuries to the teeth of 4- to 6-year-old children living in Gulbarga City, India, to determine prevalence of such dental traumatic injuries at the ages of 4, 5, and 6 years and to compare the prevalence of these injuries between male and female children. METHODS: A cross-sectional survey was performed. It consisted of a clinical examination of upper and lower deciduous anterior teeth by one examiner and an interview using a questionnaire with a sample of 1500 children aged 4 to 6 years who attended kindergarten and primary schools in Gulbarga city. Garcia-Godoy's (1981) classification was used to classify the traumatic injuries. Intra-examiner consistency was assessed by kappa values on tooth-by-tooth basis. The chisquare test was used to analyse any gender and age differences. RESULTS: The prevalence of traumatic dental injuries was 76.13%, of which crown fracture with enamel involvement of teeth was the most prevalent, followed by crown fracture with both enamel and dentine involvement. Significant and highly significant differences were found between boys and girls for discoloration of teeth (P<0.05), crown fracture involving enamel (P<0.001) and crown fracture involving both enamel and dentine (P<0.001). The prevalence of traumatic dental injuries in the 5-year-old children was higher than that in the 4- and 6-year-olds. The commonest cause of injury was due to a fall (60%) and in 40% of cases of traumatic injury, they occurred in a field/playground. CONCLUSIONS: The prevalence of traumatic injuries to the anterior teeth of the 4- to 6-year-olds who took part in this study was very high. There is a need to run educational programmes to increase parents' awareness of the risks of dental trauma.


Asunto(s)
Diente Canino/lesiones , Incisivo/lesiones , Fracturas de los Dientes/epidemiología , Diente Primario/lesiones , Accidentes por Caídas/estadística & datos numéricos , Factores de Edad , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Esmalte Dental/lesiones , Pulpa Dental/lesiones , Dentina/lesiones , Femenino , Humanos , India/epidemiología , Masculino , Juego e Implementos de Juego/lesiones , Prevalencia , Factores Sexuales , Corona del Diente/lesiones , Decoloración de Dientes/epidemiología , Movilidad Dentaria/epidemiología
17.
Orthodontics (Chic.) ; 13(1): e66-75, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22567656

RESUMEN

AIM: To analyze the influence of bracket base mesh geometry on the stresses generated in the tooth-cement-bracket continuum by a shear/peel load case and to compare the stress generated by three different loads (masticatory, peel, and twisting) on the bracket mesh base by employing a three-dimensional (3D) finite element computer model. METHODS: A validated 3D finite element model of the bracket-cement-tooth system was constructed consisting of 40,536 nodes and 49,201 finite elements. RESULTS: An increase in the diameter of the bracket mesh base wire resulted in a decrease in the stress at the enamel and cement. Increase in wire spacing (200 to 500 mm) increased the stresses in the enamel and cement at all wire diameters, but within the impregnated wire mesh, the major stress decreased with the increase in the wire spacing. Peel load produced comparatively less stress on enamel than masticatory and twisting force. CONCLUSION: Alteration in mesh spacing and wire diameter influences the magnitude and distribution of stresses within the bracket-cement-tooth continuum. Peel load and twisting load are best to debond the bracket since they produced minimal stress on the enamel, which is suggestive of lower chances of enamel damage.


Asunto(s)
Cementos Dentales , Soportes Ortodóncicos , Simulación por Computador , Recubrimiento Dental Adhesivo , Cementos Dentales/química , Análisis de Elementos Finitos , Humanos , Estrés Mecánico , Resistencia a la Tracción
18.
Dent Res J (Isfahan) ; 9(5): 619-23, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23559929

RESUMEN

BACKGROUND: To assess the prevalence of malocclusion and to determine the different occlusal characteristics in primary dentition of 4 to 6 years old children in India. MATERIALS AND METHODS: The target population comprised 4 to 6 years old children attending different nursery, kindergarten and primary schools of Bagalkot city. Stratified cluster random sampling procedure was executed to collect the representative sample. Each subject was assessed for various occlusal characteristics. RESULTS: Occlusal characteristic found were flush terminal plane (52.5%), class I canine relationship (84%), maxillary developmental spaces (35.4%), primate spaces in maxilla (47.6%), mandibular crowding (4.6%), mandibular midline shift (5.6%), anterior multiple tooth crossbite (1.3%), scissors bite (0.6%), anterior open bite (1%), over bite of 0-2 mm (81.6%) and overjet of 0-2 mm (84.5%). The age wise difference for the occlusal characteristics was statistically significant. CONCLUSIONS: The data revealed that most of the children had malocclusion. This highlights the importance of identifying children who are in need of orthodontic treatment for dental health or aesthetic reasons.

19.
Oral Health Prev Dent ; 9(1): 17-27, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21594203

RESUMEN

PURPOSE: To record, determine and discuss the gender influence on the overall prevalence of occlusal characteristics of primary dentition of 4- to 6-year-old children of Bagalkot City, India. MATERIALS AND METHODS: A total of 1000 children (583 boys and 417 girls) 4 to 6 years old were evaluated clinically for primary molars, primary canines, developmental spaces, measurements of overjet and overbite, crowding, anterior or posterior cross bite, midline discrepancies, lateral profile, as well as assessment of the presence of lip incompetency. A stratified cluster random sampling procedure was executed to collect the representative sample. RESULTS: Highly significant differences between males and females were observed for the prevalence of flush terminal plane molar relationship, class I and II canine relationship, overjet and overbite of 0 to 2 mm, and for both convex and straight profile. A significant difference was seen for the occurrence of mesial step and asymmetric molar relationship, presence of developmental and primate spaces, shift in maxillary dental midline, presence of both single tooth anterior and bilateral posterior cross bite, overjet of 2 to 4 mm and convex profile. CONCLUSIONS: The data revealed that most of the children had a malocclusion and that there was a significant difference between male and female occlusal characteristics. This highlights the importance of identifying children who are in need of orthodontic treatment for dental health or aesthetic reasons. The study also indicated that the prevalence of most of the occlusal characteristics were comparable with other communities, but there existed substantial differences in prevalence of some traits.


Asunto(s)
Maloclusión/epidemiología , Distribución de Chi-Cuadrado , Niño , Preescolar , Análisis por Conglomerados , Estudios Transversales , Diastema , Femenino , Humanos , Masculino , Mordida Abierta/epidemiología , Sobremordida/epidemiología , Prevalencia , Factores Sexuales , Diente Primario
20.
Aust Orthod J ; 24(2): 91-5, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19113072

RESUMEN

AIMS: To assess the attractiveness of dentofacial midline discrepancies during smiling, and to determine if the ratings were influenced by the gender of the judges. METHODS: Twenty non-dental undergraduate students (10 males, mean age: 33.5 years; 10 females, mean age: 31.2 years) and 20 orthodontists (10 males, mean age: 36.6 years; 10 females, mean age: 34.3 years) assessed frontal photographs of the same smiling adult female with coincident midlines, and images of the same person with the upper dental midline shifted 2 mm and 4 mm to the right and left of the facial midline. The judges scored the attractiveness of the smile using 5-point scale. RESULTS: Both the students and the orthodontists considered that the images were less attractive as the dentofacial midline discrepancy increased. More orthodontists than undergraduate students, and more female orthodontists than male orthodontists, considered a 4 mm discrepancy between the dental and facial midlines as unattractive. CONCLUSION: Dental to facial midline discrepancies reduce dentofacial attractiveness. Discrepancies of 2 mm or more are likely to be noticed by both orthodontists and non-dental university students. Orthodontic treatment objectives should include correction of the dental midline discrepancies to within 2 mm of the facial midline.


Asunto(s)
Estética Dental/psicología , Sonrisa , Adulto , Femenino , Percepción de Forma , Humanos , Masculino , Maloclusión/psicología , Ortodoncia , Fotografía Dental , Factores Sexuales
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