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1.
Niger J Clin Pract ; 23(8): 1120-1126, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32788490

RESUMO

Background: Dental arch dimensions are important considerations in orthodontic treatment planning and monitoring. Objective: This study aimed to compare the dental arch dimensions in wind and non-wind instrument players (WIP and non-WIP). Methods: This was a cross-sectional study which compared a group of 50 male subjects aged 18-45 years that had been playing wind instruments for a minimum of 2 years with a control group matched for age in the same environment. The arch dimensions were assessed for both groups by measuring their dental casts using a digital caliper. Data was analyzed using statistical Software Package for Social Sciences (SPSS Inc, Chicago, IL) version 17. Statistical significance level was set at P < 0.05. Results: The mean number of years of playing wind instrument among the WIP was 9.26 ± 6.21 years. All the maxillary arch dimensions were larger in the WIP group except for the palatal depth while the mandibular arch parameters in the non-WIP group were larger than the WIP group except the mandibular arch length. The differences were not statistically significant (P > 0.05). The mean maxillary inter-canine width (37.48 ± 1.12 mm), inter-molar width (57.27 ± 1.99 mm), arch length (29.80 ± 2.2.09 mm), and palatal depth (22.21 ± 2.33 mm) for class B instrument (Saxophone and clarinet) players were larger than either the class A instrument (Trumpet and trombone) players or the non-WIP group. These differences were not statistically significant (P > 0.05). Conclusions: Playing a wind instrument as well as the type of instrument played, duration, and frequency of play did not significantly affect dental arch dimensions.


Assuntos
Arco Dental/anatomia & histologia , Oclusão Dentária , Música , Adolescente , Adulto , Cefalometria , Estudos Transversais , Dente Canino , Feminino , Humanos , Masculino , Maxila , Pessoa de Meia-Idade , Ortodontia , Adulto Jovem
2.
Am J Orthod Dentofacial Orthop ; 157(5): 619-630, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32354435

RESUMO

INTRODUCTION: This study aimed to examine the role of dentofacial morphology in discriminating semi-isolated indigenous groups. These populations present a similar pattern of dietary habits. Studies in human genetics have reported a large intertribal genetic distance and low intratribal variation. METHODS: This study was conducted following the Strengthening the Reporting of Observational Studies in Epidemiology guidelines. Face dimensions were measured through facial photogrammetry, and dental arches and tooth size were evaluated using plaster models. A total of 98 subjects in the permanent dentition and belonging to 4 indigenous groups were analyzed: Arara-Iriri (n = 20), Arara-Laranjal (n = 33), Assurini (n = 25), and Xicrin-Kayapó (n = 20). The random and systematic errors were verified using the Dahlberg formula and the intraclass correlation coefficient (ICC), respectively. In order to evaluate the discrimination of the variables to identify the indigenous groups, a discriminant analysis was performed (P <0.05). RESULTS: A small causal error (Dahlberg, 0.13-1.81) and excellent replicability (ICC, 0.75-0.99) for face dimensions as well as for models (Dahlberg, 0.10-0.68; ICC, 0.94-0.99) were observed. The discriminant analysis allowed the identification of 4 populations by facial and dental arch dimensions and tooth size. Dentofacial biometry revealed an accuracy of 98% for females and 100% for males, which confirms a high intragroup homogeneity and considerable intergroup heterogeneity for dentofacial features. CONCLUSIONS: Biometric measurements of the human face added with tooth size and dental arch dimensions are very useful to identify remote indigenous populations with high accuracy. Supported by previous studies in human genetics, these findings reinforce the role of genetic variation in the determination of dentofacial features.


Assuntos
Biometria , Grupos Populacionais , Arco Dental/anatomia & histologia , Face/anatomia & histologia , Feminino , Humanos , Índios Sul-Americanos , Masculino , Fotogrametria
3.
BMC Oral Health ; 20(1): 97, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264943

RESUMO

BACKGROUNDS: Intraoral scanner (IOS) accuracy is commonly evaluated using full-arch surface comparison, which fails to take into consideration the starting position of the scanning (scan origin). Previously a novel method was developed, which takes into account the scan origin and calculates the deviation of predefined identical points between references and test models. This method may reveal the error caused by stitching individual images during intraoral scan. This study aimed to validate the novel method by comparing the trueness of seven IOSs (Element 1, Element 2, Emerald, Omnicam, Planscan, Trios 3, CS 3600) to a physical impression digitized by laboratory scanner which lacks linear stitching problems. METHODS: Digital test models of a dentate human cadaver maxilla were made by IOSs and by laboratory scanner after polyvinylsiloxane impression. All scans started on the occlusal surface of the tooth #15 (universal notation, scan origin) and finished at tooth #2. The reference model and test models were superimposed at the scan origin in GOM Inspect software. Deviations were measured between identical points on three different axes, and the complex 3D deviation was calculated. The effect of scanners, tooth, and axis was statistically analyzed by the generalized linear mixed model. RESULTS: The deviation gradually increased as the distance from scan origin increased for the IOSs but not for the physical impression. The highest deviation occurred mostly at the apico-coronal axis for the IOSs. The mean deviation of the physical impression (53 ± 2 µm) was not significantly different from the Trios 3 (156 ± 8 µm) and CS 3600 (365 ± 29 µm), but it was significantly lower than the values of Element 1 (531 ± 26 µm), Element 2 (246 ± 11 µm), Emerald (317 ± 13 µm), Omnicam (174 ± 11 µm), Planscan (903 ± 49 µm). CONCLUSIONS: The physical impression was superior compared to the IOSs on dentate full-arch of human cadaver. The novel method could reveal the stitching error of IOSs, which may partly be caused by the difficulties in depth measurement.


Assuntos
Arco Dental , Técnica de Moldagem Odontológica/instrumentação , Maxila/diagnóstico por imagem , Desenho Assistido por Computador , Arco Dental/anatomia & histologia , Modelos Dentários , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional
4.
Homo ; 71(1): 19-28, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31939990

RESUMO

Background: Sex determination is the first step in personal identification in the forensic field. This study aimed to evaluate sexual dimorphism by using palatal rugae pattern and odontometrics, construct an Egyptian equation for sex determination using the discriminant function analysis. Participants and methods: The study sample included 200 participants of both sexes. Maxillary arch impressions were taken with alginate impression material using stainless steel impression tray. Identification and measurements were done to study the palatal rugae pattern, dental arch dimensions, and maxillary canine. Results: There was a highly statistically significant difference between males and females with higher male values regarding the total palatal rugae number, wavy rugae number, primary rugae number, arch length, width, maxillary canine right width, maxillary canine left width, intercanine distance, and maxillary canine right index while there was a highly statistically significant difference with higher female value regarding the straight rugae numbers. Four Egyptian equations were constructed using discriminant function analysis to determine the sex of an unidentified person. Conclusions: Palatal rugae pattern, dental arch dimensions, and maxillary canine index can be considered as useful tools for sex determination in the forensic field.


Assuntos
Odontometria/métodos , Análise para Determinação do Sexo/métodos , Adulto , Dente Canino/anatomia & histologia , Arco Dental/anatomia & histologia , Análise Discriminante , Egito , Feminino , Humanos , Masculino , Palato/anatomia & histologia , Projetos Piloto , Adulto Jovem
5.
Eur J Orthod ; 42(1): 30-35, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31586178

RESUMO

OBJECTIVES: The present study validated data that had been reported to the Swedish Quality Registry for Cleft Lip and Palate (CLP) under new requirements from 2016, when use of the 5-year-old (5YO) and the Modified Huddart and Bodenham (MHB) indices for rating occlusion in children born with unilateral CLP (UCLP) was introduced. MATERIALS AND METHODS: The sample included blinded study casts (n = 97) and photos (n = 4) of 5-year-old children who had been born with UCLP in 2009-2011 and were enrolled at one of six cleft centres in Sweden. Fourteen orthodontists from the centres assessed the patients (n = 101) using the 5YO and the MHB indices. Median 5YO and MHB scores of the 14 assessments were compared with original registry data (n = 61). Each centre devised code keys to protect the identities of their patients in the registry. RESULTS: Interrater agreement among the 14 orthodontists was good for the 5YO index (quadratic-weighted kappa: 0.72-0.92) and the MHB index (intraclass correlation coefficient: 0.991-0.994). Comparisons of median 5YOs for each identifiable child with their registry data (n = 61) found total agreement for 70.5 per cent. Comparisons between median MHBs and registry data showed very good or good agreement in 93.4 per cent of the cases. LIMITATIONS: Two teams lost their code keys, which reduced the sample to 61 patients. CONCLUSIONS: The dentoalveolar outcome data in the CLP registry was trustworthy. There was good agreement among the Swedish cleft teams assessing the 5YO and MHB indices in children born with UCLP at age 5 years.


Assuntos
Fenda Labial , Fissura Palatina , Arco Dental , Sistema de Registros , Pré-Escolar , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Arco Dental/anatomia & histologia , Arco Dental/cirurgia , Humanos , Reprodutibilidade dos Testes , Suécia , Resultado do Tratamento
6.
Eur J Orthod ; 42(1): 1-7, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31579909

RESUMO

BACKGROUND AND TRIAL DESIGN: The Scandcleft intercentre study evaluates the outcomes of four surgical protocols for treatment of children with unilateral cleft lip and palate (UCLP). Originally 10 cleft centres in Denmark, Finland, Norway, Sweden, and the UK participated in a set of three randomized trials of primary surgery. Three groups of centres (Trials 1, 2, and 3) tested their traditional local surgical protocols (Arms B, C, and D) against a common protocol (Arm A). OBJECTIVES: To evaluate dental arch relationships at age 8 years after four different protocols of primary surgery for UCLP. These results are secondary outcomes of the overall trial. METHODS: Study models of 411 children (270 boys, 141 girls) with non-syndromic UCLP at a mean age of 8.1 (range 7.0-10.0) years were available. Dental arch relationships were analysed using the GOSLON Yardstick by a blinded panel of 11 orthodontists. To assess reliability, Kappa statistics were calculated. The trials were tested statistically with t-tests. RESULTS: Comparisons within each trial showed no statistically significant differences in the mean 8-year index scores or their distributions between the common protocol and the local team protocol. The mean index scores were Trial 1: Arm A 3.03, Arm B 2.82, Trial 2: Arm A 2.78, Arm C 2.64, and Trial 3: Arm A 3.06, Arm D 3.08. Comparisons between the trials detected a significantly (P < 0.005) better mean index score Trial 2 Arm C than in Trial 3 Arm D. The intra- and inter-rater reliabilities were acceptable. CONCLUSION: The results of these three trials do not provide evidence that one surgical protocol is better than the others. TRIAL REGISTRATION: ISRCTN29932826.


Assuntos
Fenda Labial , Fissura Palatina , Arco Dental , Criança , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Arco Dental/anatomia & histologia , Arco Dental/cirurgia , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Resultado do Tratamento
7.
Angle Orthod ; 90(1): 23-30, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31368778

RESUMO

OBJECTIVES: To investigate the efficiency and movement pattern of upper arch expansion using Invisalign aligners. The correlation between the amount of designed expansion and the efficiency of bodily expansion was evaluated, as were the initial molar torque and efficiency of bodily expansion. MATERIALS AND METHODS: Twenty Chinese adult patients who underwent arch expansion with Invisalign aligners were included in this study. Records of pretreatment (T0 stage) and immediately after completing the expansion phase (T1 stage) were collected, including digital models and cone-beam computed tomography. Dolphin 3D, Geomagic Studio 12.0, and Meazure software were employed to measure data and calculate differences between the expected and actual outcomes. RESULTS: There were significant differences between the expected and actual expansion amounts (P< .05). The average expansion efficiencies of the upper canine crown, first premolar crown, second premolar crown, and first molar crown were 79.75 ± 15.23%, 76.1 ± 18.32%, 73.27 ± 19.91%, and 68.31 ± 24.41%, respectively. The average efficiency of bodily expansion movement for the maxillary first molar was 36.35 ± 29.32%. Negative correlations were found between preset expansion amounts and the efficiency of bodily expansion movement (P < .05), and between initial maxillary first molar torque and efficiency of bodily expansion movement (P < .05). CONCLUSIONS: Aligners could increase the arch width, but expansion was achieved by tipping movement. The evaluation of initial position and preset of sufficient root-buccal torque of posterior teeth were necessary due to the lower efficiency of bodily buccal expansion by the Invisalign system.


Assuntos
Arco Dental , Aparelhos Ortodônticos Removíveis , Técnicas de Movimentação Dentária , Adulto , Arco Dental/anatomia & histologia , Humanos , Maxila , Dente Molar , Resultado do Tratamento
8.
Angle Orthod ; 90(2): 233-238, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31469593

RESUMO

OBJECTIVE: The objective of this study was to compare the effects on upper dental arch size and shape after maxillary expansion with Hyrax, Quad-helix, and a differential opening expander in bilateral cleft lip and palate (BCLP) patients. MATERIALS AND METHODS: Seventy-five BCLP patients were divided into three groups: Hyrax (H), Quad-helix (QH), and Expander with differential opening (EDO). Digital models were obtained before (T1) and after 6 months (T2) of maxillary expansion. Twelve landmarks were placed by one investigator on T1 and T2 dental models of each group, and x,y coordinates for each landmark were collected. For dental arch size analysis, centroid size of each dental arch at T1 and T2 was calculated from raw coordinates and was used as the measure of size. Procrustes Analysis was performed for dental arch shape analysis. Analysis of variance was used to compare the groups for size and shape differences (P < .05). RESULTS: There were no significant dental arch size differences among the expanders at T1 or T2. Differences in arch shape were found between all groups at T2. Intragroup arch shape showed a significant variation for the QH and EDO groups. while it remained stable in the H group. CONCLUSIONS: Both the QH and the EDO create dental arch shape changes with greater intercanine than intermolar increase. The H does not change the dental arch shape.


Assuntos
Fenda Labial , Fissura Palatina , Arco Dental , Técnica de Expansão Palatina , Arco Dental/anatomia & histologia , Humanos , Maxila
9.
Int. j. odontostomatol. (Print) ; 14(3): 393-399, 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1114913

RESUMO

El examen de modelos es una de las múltiples herramientas diagnósticas que posee la ortodoncia y ortopedia dentomáxilofacial. Los valores con que se construyó su norma estadística están basados en poblaciones específicas y no reflejan las diferencias morfológicas existentes en el complejo cráneofacial entre las distintas etnias. El propósito de esta investigación fue identificar las longitudes transversales y sagitales de los maxilares de la población adulta mestiza chilena con oclusión normal y compararlas con el índice de Korkhaus basado en una población adulta caucásica alemana. Se reclutaron 20 estudiantes de pregrado de la Facultad de Odontología de la Universidad de Valparaíso con oclusión normal. Se registraron ambas arcadas dentarias con yeso y se aplicó el índice de Korkhaus: se midió la longitud interpremolar, la longitud intermolar, la longitud anterior superior y la longitud anterior inferior. La comparación entre los valores de la muestra y los valores referenciales del índice de Korkhaus fue hecha con la prueba de rangos de Wilcoxon mediante el software estadístico STATA 15.0 y se consideraron significativos valores de p<0,05. Se encontró una diferencia estadísticamente significativa en el valor de la longitud anterior superior (p-0,013); para la longitud interpremolar (p-0,9552) la longitud intermolar (p-0,8223) y la longitud anterior inferior (p-0,0452) no se hallaron diferencias. La mayor magnitud de la longitud anterior superior de la arcada dentaria respecto a la población adulta caucásica alemana se debe al rasgo de protrusión dentaria presente en la población mestiza chilena, lo cual no altera las características de una oclusión normal.


The model exam is one of many diagnostic tools in orthodontics and dentomaxillofacial orthopedics. The values on which the statistical norm were constructed, are based on specific populations and they do not reflect the morphological differences in the craniofacial complex between the different ethnic groups. The purpose of this study was to identify the transverse and sagittal maxillary and mandibular lengths of the Chilean mestizo adult population with normal occlusion, and compare them with the Korkhaus index based on a German Caucasian adult population. For this study 20 undergraduate students with normal occlusion were recruited from the Faculty of Dentistry of the University of Valparaíso. Both upper and lower dental casts were obtained from each student, and Korkhaus index was applied: the interpremolar length, intermolar length, upper anterior length and lower anterior length were measured. Comparison between the values of the sample and the reference values of the Korkhaus index was made with the Wilcoxon range test using the STATA 15.0 statistical software and significant values of p <0.05 were considered. A statistically significant difference was found in the value of the upper anterior length (p-0.013); for the interpremolar length (p-0.9552) the intermolar length (p-0.8223) and the lower anterior length (p-0.0452) no differences were found. The greater magnitude of the dental arch upper anterior length compared to the German Caucasian adult population is due to dental protrusion present in the Chilean mestizo population, which does not affect the normal occlusion characteristics.


Assuntos
Humanos , Arco Dental/anatomia & histologia , Valores de Referência , Grupos Étnicos , Chile , Estudos Transversais , Modelos Dentários , Arcada Osseodentária/anatomia & histologia
10.
Sci Rep ; 9(1): 18526, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811230

RESUMO

This study aimed to investigate changes in types of dental arch form during adolescence and explore adolescent changes in size and form of dental arch. Hong Kong Chinese were recruited and digital dental arch models were obtained at ages 12, 15, and 18 years. Geometric morphometrics was used to investigate adolescent changes of dental arch form. There were 225 participants from whom digital models at all three age periods were available. Three types of dental arch form were identified through clustering. Significant changes (p < 0.001) in types of dental arch form were noted during age 12-18 years. During age 12-18 years, significant changes in centroid size and form of dental arch were observed (p < 0.001). No significant changes were observed during 15-18 years. Adolescent changes of dental arch form occur primarily during age 12-15 years, whereas dental arch form was relatively stable during age 15-18 years.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Arco Dental/crescimento & desenvolvimento , Adolescente , Fatores Etários , Cefalometria/estatística & dados numéricos , Criança , Arco Dental/anatomia & histologia , Feminino , Hong Kong , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos
11.
Am J Orthod Dentofacial Orthop ; 156(6): 870-877, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31784021

RESUMO

INTRODUCTION: This study aimed to evaluate the ability of dental clinicians to predict posttreatment dental arch forms in patients with malocclusion with the aid of 3D imaging and digital software in comparison with a conventional method. METHODS: Pretreatment and posttreatment dental plaster casts of 100 patients (200 maxillary models and 200 mandibular models) were selected. Three orthodontists selected the best-fitted archwires among 5 commercially available preformed nickel-titanium archwires using 2 methods. In the conventional method, they fit the archwires to pretreatment casts, and in the digital method, they fit the scanned wire to a 3D digital model, using Ortho-Aid, a locally developed 3D software, using clinical bracket points as reference for wire fitness. The predicted posttreatment archwire in each method was compared with the best-fit archwire on the actual posttreatment model of each patient in both methods, and the level of agreement was calculated. The interobserver agreement between the 3 orthodontists in each method was evaluated using intraclass correlation coefficient and the Dahlberg formula. RESULTS: Orthodontists predicted the final treatment outcome in 50% of cases using the conventional method and 58% using the digital method. However, the range of method error was significantly higher in the conventional method (0.425-3.853 mm for the conventional vs 0.451-0.584 mm for the digital). CONCLUSIONS: Although the clinicians' ability to predict the final dental arch form after orthodontic treatment and the agreement between clinicians increased by the use of digital equipment, orthodontists can predict the final arch form in about 60% of patients.


Assuntos
Arco Dental , Imageamento Tridimensional , Fios Ortodônticos , Ortodontia Corretiva , Ligas Dentárias , Arco Dental/anatomia & histologia , Arco Dental/diagnóstico por imagem , Modelos Dentários , Previsões , Humanos , Mandíbula , Software
12.
Niger J Clin Pract ; 22(10): 1448-1456, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31607738

RESUMO

Objective: The purpose of this study was to investigate a relationship between gingival tissue biotypes and arch form with Schneiderian membrane thickness, using limited cone beam computed tomography. Materials and Methods: A total of 90 subjects were selected. For each subject three parameters were assessed - gingival biotype - clinically by Probe transparency method as thin or thick and coded as 0 and 1, respectively, gingival thickness and Schneiderian membrane thickness in mm, arch form as square, oval, or tapered (radiographically by cone beam computed tomography images). Central incisors and first molars were assessed for gingival biotype and gingival thickness and Schneiderian membrane thickness was determined at 16. Numerical data were estimated for normal distribution. Analysis of Variance test was followed by Tukey honestly significant difference test and Pearson's correlation coefficient test for analysis. Results: Thin gingival biotype was found associated with the central incisors and thick gingival biotype with molars. Limited cone beam computed tomography scans evaluation revealed highest prevalence of square arch form followed by oval, and tapered. The average thickness of the Schneiderian membrane was 1.18 ± 0.43 mm on left side and 1.09 ± 0.41 mm on right side with a range of 0.50 - 2.00 mm. Mean Schneiderian membrane thickness was more in case of thick gingival biotype and with square arc form both on right and left sides. Conclusions: The Schneiderian membrane thickness was positively and highly associated with gingival biotype. The gingival biotype and arch form had significant effect on Schneiderian membrane thickness and can provide valuable clinical information on Schneiderian membrane thickness preoperatively for implant placement and sinus lift procedures.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Implantes Dentários , Gengiva/diagnóstico por imagem , Mucosa Nasal/diagnóstico por imagem , Arco Dental/anatomia & histologia , Arco Dental/diagnóstico por imagem , Feminino , Gengiva/anatomia & histologia , Humanos , Masculino , Dente Molar , Adulto Jovem
13.
Homo ; 70(3): 185-192, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31486821

RESUMO

The aim was to analyze the changes in mandibular dental arch shape during adolescence and assess its relation to late mandibular incisor crowding. Longitudinal study included 68 orthodontically untreated subjects (49% female) and analyzed their data for the ages of 12, 15, 18 and 21 years. Measurements included anterior arch depth, intercanine, interpremolar/anterior and intermolar/posterior width, Little's Irregularity and Bolton's index and the ratio between anterior arch depth and width. Males had significantly greater posterior widths than females at any age (p < 0.05). The anterior arch depth continuously decreased (p < 0.05), while width increased after the age of 18 years. Mandibular incisor crowding increased during all investigated periods (p < 0.05). The increase of intercanine width at 12-21 years of age reduced the risk for mandibular incisor crowding in the same period by 74% (OR: 0.265: 95% CI 0.076-0.931; p = 0.045). The shape of mandibular dental arch continues to change during adolescence becoming more squared while mandibular incisor crowding increases. The increase in mandibular intercanine width reduces the risk of crowding.


Assuntos
Arco Dental , Incisivo , Má Oclusão/patologia , Adolescente , Adulto , Antropologia Física , Criança , Arco Dental/anatomia & histologia , Arco Dental/crescimento & desenvolvimento , Arco Dental/patologia , Feminino , Humanos , Incisivo/anatomia & histologia , Incisivo/patologia , Estudos Longitudinais , Masculino , Odontometria , Adulto Jovem
14.
Okajimas Folia Anat Jpn ; 96(1): 31-46, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31462623

RESUMO

Dental arch length, bilateral intermolar distance, morphology of the anterior teeth, and bilateral intercanine distance have been reported as factors influencing the determination of dental arch form. However, studies evaluating the factors that influence the determination of the above-mentioned components are limited. Therefore, to verify these points, the present study aimed to examine factors influencing the determination of dental arch form using statistical methods.Data obtained from sample dental casts were analyzed using principal component and cluster analyses. By principal component analysis, 23 sets of information were summarized into three components for the maxilla and four for the mandible. As a result of cluster analysis using principal component scores, the maxillary and mandibular dental arches were classified into four forms, respectively.Dental arch length is an important indicator of dental arch size and is influenced by the bilateral interincisor distance of the maxilla and mandible, and the mesiodistal crown width of the incisors and premolars. In the mandible, canine width also affects dental arch length. Dental arch width also influences the determination of dental arch form. However, the distance between the anterior teeth and the distance between the molars are independent and have no effect on each other.


Assuntos
Arco Dental/anatomia & histologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
15.
Am J Orthod Dentofacial Orthop ; 156(1): 94-103, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31256848

RESUMO

INTRODUCTION: Self-ligating appliances are purposed to expand the arches, but evidence on stability of the result is lacking. We measured the width of maxillary and mandibular arches and torque changes after treatment with the use of passive self-ligating appliances and assessed stability at the 2-year follow-up. METHODS: Maxillary and mandibular 3-dimensional (3D) models from 32 subjects (mean initial age 14.9 ± 0.9 years), consecutively treated with the use of self-ligating appliances, were obtained before, immediately after, and 2 years after treatment. Dental arches were examined with the use of 3D software to evaluate differences in transverse arch dimensions and torque values. RESULTS: An incremental increase of arch widths was recorded, especially regarding maxillary and mandibular premolars. The increase in the transverse diameters was associated with a significant positive torque gain. No significant changes in arch perimeter and depth were recorded. In the retention period, slight significant changes in transverse diameters were recorded, and a transverse diameter constriction detected. Torque values remained almost unchanged in the follow-up period. CONCLUSIONS: Transverse arch dimensions, along with torque values, increased significantly after treatment with the use of a passive self-ligating appliance. In the 2 years following treatment, a tendency to transverse diameter restriction, especially for the maxillary and mandibular premolars, was observed.


Assuntos
Arco Dental/anatomia & histologia , Má Oclusão/terapia , Aparelhos Ortodônticos , Técnica de Expansão Palatina , Técnicas de Movimentação Dentária/métodos , Torque , Adolescente , Adulto , Análise de Variância , Dente Pré-Molar , Desenho Assistido por Computador , Técnica de Fundição Odontológica , Modelos Dentários , Feminino , Seguimentos , Humanos , Imageamento Tridimensional/métodos , Masculino , Má Oclusão/patologia , Mandíbula , Maxila , Níquel , Desenho de Aparelho Ortodôntico , Técnica de Expansão Palatina/instrumentação , Software , Titânio , Coroa do Dente/anatomia & histologia , Técnicas de Movimentação Dentária/instrumentação , Resultado do Tratamento , Adulto Jovem
16.
Eur. j. anat ; 23(4): 273-277, jul. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-183001

RESUMO

A thorough knowledge of external dental root morphology is fundamental for having successful endodontic, orthodontic and surgical treatments in dentistry. The aim of this anatomical study was to determine the incidence of tooth dilacerations in Kerman, a province in the Southeastern Islamic Republic of Iran. A cross-sectional study was performed on a total of 3150 teeth from 800 PA radiographs; 100 radiographs from each 8 anatomic divisions of the dental arch, within a Kerman population. The numbers of radiographs were equal between 2 genders; 400 from females and 400 from males. Radiographs were studied by 3 specialists in this field in order to determine and record the prevalence and distribution of dilacerations in different teeth of this population. Amongst the total of 3150 teeth from 800 radiographs, 52 teeth (1.65%) showed dilacerations. The prevalence of this anomaly was 7.5% in males and 5% in females, and the distribution was almost equal between different teeth of the maxilla (2%-4%); meanwhile in the mandible, the maximum prevalence was in third molars (14%) and the rate was nil in anterior teeth (Spss and Excel softwares, IBM). The prevalence of tooth dilacerations was almost equal between genders in the Kerman population that was studied. The findings indicated that the presence of dilacerated roots was more prevalent in females in the mandibular arch, while this anomaly was more prevalent in males in the maxillary arch. Interestingly, none of the mandibular incisor teeth displayed this anomaly


No disponible


Assuntos
Humanos , Masculino , Feminino , Dentição Permanente , Arco Dental/anatomia & histologia , Arco Dental/anormalidades , Mandíbula/anatomia & histologia , Maxila/anormalidades , Irã (Geográfico) , Arco Dental/diagnóstico por imagem
17.
Georgian Med News ; (287): 111-114, 2019 Feb.
Artigo em Russo | MEDLINE | ID: mdl-30958300

RESUMO

Nowadays new efficient methods of dental correction and modern methods of abnormal bite correction are suggested. In this regard, seems to be important to study the existence of individual anatomical variability range of the maxilla and its structures. The research has been conducted on 100 bone samples of integral and fragmented skulls from the collections of anatomy department of Kharkiv National Medical University. In the conditions of research, detailed osteometry of the maxilla has been took place. Therefore, measurements have been included: length (from the posterior margin of the front incisive alveoli to the posterior margin of the hard palate); width (between the inner margins of the second molars alveoli); length (perimeter) of the dental arch. The length of the maxillary alveolar arch gradually increases from brachycephalic to mesocephalic and dolichocephalic of both genders. The width of the upper alveolar arch reaches the maximum values in brachycephalic type, an intermediate place is occupied by mesocephalic, dolichocephalic type of the skull corresponds to the minimal range. In adulthood have been found the prevalence of right-sided asymmetry of the external margin of the upper alveolar arch and hence the similar localization of the maxilla teeth row, due to the right-sided mastication type or its predominance throughout the life. According to received data, there are three main forms of upper alveolar arch in adulthood: expanded-arch, which differs by deployed curvature around the perimeter and typical for brachycephalic; medium-arch with the presence of different length along the perimeter in mesocephalic; narrow-arch with the predominance of longitudinal perimeters in dolichocephalic type. Maxillary dental arch lies along the lower edge of the teeth, starting from the frontal incisors. Alveolar arch passes through the alveolar crest (lower edge of the gums). Basal arch is going on the tops of the teeth roots, otherwise known as apical arch. Given that, the crowns of the upper jaw teeth are always inclined vestibulary and roots of teeth - orally. Their ratio to the maxilla expressed that the widest perimeter has dental arch, middle position - alveolar arch and the smallest one is apical. The last one withstands the maximal masticatory pressure and hence beginning of the maxillary buttresses at this level.


Assuntos
Arco Dental/anatomia & histologia , Maxila/anatomia & histologia , Dente Molar/crescimento & desenvolvimento , Oclusão Dentária , Feminino , Humanos , Masculino , Desenvolvimento Maxilofacial , Raiz Dentária
18.
BMC Oral Health ; 19(1): 66, 2019 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-31029133

RESUMO

BACKGROUND: Studies focusing on accuracy of intraoral digital models in the palatal region are scarce. The present study aimed to investigate the influence of different scanning sequences on palatal trueness and to assess deviation and distribution character of trueness in palate. METHODS: Overall, 35 participants accepted three types of procedures to acquire upper digital models. Indirect models digitalised from plaster models were considered as the reference. Two direct digital models were acquired using TRIOS 3 POD intraoral scanners, namely Groups Tr1 and Tr2, wherein intraoral scanning differed in terms of palatal scanning sequences. Based on a modified dental-level superimposition method, 3D measurements of trueness in palate and palatal vault region (PVR) for palatal stable regional superimposition in Groups Tr1 and Tr2, respectively, were performed. Absolute deviations were measured for trueness, while signed deviations were analysed for shape distortion. Colour-coded maps were used for quantitative analysis of deviation distribution pattern. Paired t test was used to analyse differences in palatal trueness between different scanning sequences. One-way repeated-measures analysis of variance and Bonferroni test were used to compare trueness measurements among different superimposition methods. Intraclass correlation coefficient (ICC) was used to verify reproducibility of the proposed method. RESULTS: Palatal trueness in Group Tr1 (118.59 ± 37.67 µm) was slightly less accurate than that (108.25 ± 33.83 µm) in Group Tr2 (p = 0.012 < 0.05). Trueness of PVR in Groups Tr1 (127.35 ± 54.11 µm) and Tr2 (118.17 ± 49.52 µm) did not differ significantly (p = 0.149). Moreover, no significant difference was noted in distortion of the palatal region and PVR in Groups Tr1 and Tr2 (p = 0.582 and 0.615, respectively). A similar pattern of palatal trueness was noted in a majority of participants (22/35). For 3D palatal trueness measurement, there were different applications for different superimposition methods. ICC for the proposed method was > 0.90. CONCLUSIONS: Scanning sequences can affect palatal trueness. Palatal scanning should be initiated at the palatal side of the posterior teeth where the initial scan begins. For 3D PVR superimposition, distal boundary of the selected region should be adjusted mesially whilst referring to intraoral digital models. TRIAL REGISTRATION: The trial has been registered (registration No: R000039467 , Trial ID: UMIN000034617, date of registration: 2018/10/24'retrospectively registered').


Assuntos
Arco Dental/anatomia & histologia , Arco Dental/diagnóstico por imagem , Materiais para Moldagem Odontológica , Técnica de Moldagem Odontológica , Planejamento de Prótese Dentária/métodos , Processamento de Imagem Assistida por Computador/instrumentação , Palato/anatomia & histologia , Desenho Assistido por Computador , Modelos Dentários , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
19.
Int Orthod ; 17(2): 312-323, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31023588

RESUMO

INTRODUCTION: Discrepancy of the upper dental midline to the facial midline plays an important role in smile aesthetic assessment. This study presents different reference points to quantify the deviation of upper dental midline to the facial midline in 2D frontal photographs. The aim was to find the most accurate, precise, and practical reference points to measure dental midline discrepancy in 2D photographs. METHODOLOGY: A modified headset with a protractor was developed in order to achieve photographs in nine standardised head positions. Six reference points were used to detect the facial midline in the 2D photographs (eyebrows "EB", inner-canthus of the eyes "ICE", alae of the nose "AN", columella "C", nasolabial folds "NLF", and the philtrum "PH"). The deviation of the maxillary dental midline from the facial midline was measured and compared with clinical measurements. STATISTICAL ANALYSIS: Standard deviations (SD), Root Mean Square Error (RMSE), Method of Moments' Estimator (MME), 2-way repeated measures ANOVA, and multi-level linear model were used to estimate the true errors. RESULTS: The different reference points responded significantly differently to changes in head position and all showed measurement errors, which increased with greater head rotation. Alae of the nose showed the least measurement error and the greatest precision in all head positions. CONCLUSION: The alae of the nose are the recommended reference points to identify the facial midline in order to quantify dental midline deviation from frontal photographs.


Assuntos
Pontos de Referência Anatômicos , Face/anatomia & histologia , Face/diagnóstico por imagem , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Fotografia Dentária/métodos , Arco Dental/anatomia & histologia , Arco Dental/diagnóstico por imagem , Estética Dentária , Assimetria Facial/diagnóstico por imagem , Humanos , Incisivo/anatomia & histologia , Lábio , Má Oclusão/diagnóstico por imagem , Má Oclusão/patologia , Nariz/anatomia & histologia , Fotografia Dentária/instrumentação , Sorriso , Anormalidades Dentárias/diagnóstico por imagem
20.
Sci Rep ; 9(1): 3101, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816230

RESUMO

This study aimed to define the width and length of the dental arch in 12-year-old Vietnamese children, and to elucidate differences between genders and among ethnic groups. A cross-sectional study was conducted in 4565 12 years-old children from the 4 major ethnic groups in Vietnam (Kinh, Muong, Thai, and Tay), with a healthy and full set of 28 permanent teeth that had never had any orthodontic treatment and with no reconstructive materials at the measured points. The mean variables in all subjects were 36.39 mm for upper inter-canine width; 46.88 mm for upper inter-first molar width; 59.43 mm for upper inter-second molar width; 10.41 mm for upper anterior length; 32.15 mm for upper posterior length 1; 45.52 mm for upper posterior length 2; 28.31 mm for lower inter-canine width; 41.63 mm for lower inter-first molar width; 54.57 mm for lower inter-second molar width (LM2W); 7.06 mm for lower anterior length (LAL); 26.87 mm for lower posterior length 1 (LP1L); and 41.29 mm for lower posterior length 2. Significant differences in these parameters between genders were found in all ethnic groups, except for LAL in the Kinh and Thai groups, and LP1L in the Tay group. Significant ethnic differences were also found in almost all parameters except LM2W in both males and females. Taken together, the representative sizes of dental arches of 12-year-old Vietnamese children have been defined. Our data indicate that there are some variations in dental arch dimensions among ethnic groups and between genders.


Assuntos
Arco Dental/anatomia & histologia , Dente/anatomia & histologia , Criança , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Odontometria , Vietnã/epidemiologia , Vietnã/etnologia
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