A influência do tratamento ortopédico nas estruturas faciais de indivíduos com má oclusão de Classe II, 1ª Divisão: um estudo comparativo

The purpose of this investigation was to comparatively evaluate the cephalometric changes in soft and hard tissues related to treatment of Class II, division 1 malocclusion with activator-headgear and Bionator appliances. Twenty-four individuals formed the activator-headgear group and twenty-five comprised the Bionator group, while other twenty-four presenting the same malocclusion did not receive any intervention and served as controls. Lateral headfilms were taken at the beginning and at the end of the observation period and were digitized with computerized cephalometrics; cephalometric analysis was performed and the results were submitted to statistical test. According to the methodology employed, our findings suggested that both appliances do not significantly alter the growth path, and also they were not able to modify the posterior inferior height and the sagittal and vertical position of the upper lip. The lower lip and the soft menton were only slightly modified by the orthopedic appliances, but the mentolabial sulcus showed a significant decrease in deepness compared to the control group. Of statistical significance, only the anterior inferior hard and soft facial heights and the lower lip height increased more in the treated groups.Esta pesquisa teve por objetivo avaliar, comparativamente, as alterações cefalométricas tegumentares e esqueléticas, decorrentes do tratamento das más oclusões de classe II, 1a divisão, com o ativador combinado com a ancoragem extrabucal e com o bionator. O grupo tratado com o ativador combinado com a ancoragem extrabucal foi composto por 24 indivíduos e o grupo tratado com o bionator compreendeu 25 pacientes, enquanto que outros 24 indivíduos compuseram o grupo controle, apresentando a mesma má oclusão, porém sem terem sido submetidos a nenhuma terapia ortodôntica. Obteve-se telerradiografias laterais de todos os indivíduos no início e final do período de observação que foram digitalizadas e seus traçados cefalométricos computadorizados realizados e submetidos ao teste estatístico. De acordo com a metodologia empregada, os resultados sugerem que ambos os aparelhos não foram capazes de alterar, significaticamente, o padrão de crescimento facial assim como a altura facial posterior inferior e o posicionamento sagital e vertical do lábio superior. Os aparelhos ortopédicos alteraram ligeiramente o lábio inferior e o mento tegumentar, porém o sulco mentolabial foi signifivativamente reduzido nos grupos tratados em comparação com o grupo controle. As alturas faciais esquelética e tegumentar, bem como a altura do lábio inferior foram significativamente aumentadas com a terapia ortopédica, alcançando diferença estatística em relação ao grupo controle

Análise retrospectiva dos resultados dos tratamentos ortodônticos e sua relação com a estabilidade pós-contenção

OBJECTIVE: The present study was designed to retrospectively evaluate Class I malocclusion cases treated with extraction of the four first premolars, aiming to establish the relationship between the quality of orthodontic treatment outcomes and the long-term occlusal stability. MATERIAL AND METHODS: The sample comprised 94 patients of both genders, presenting Class I malocclusion, treated with extractions of the four first premolars and Edgewise mechanics. All the patients selected were whites, being 50 males and 44 females. The mean pretreatment age was 13.46 years (s.d. 1.8). The mean treatment time was 2.09 years (s.d. 0.58), the mean retention time was 1.63 years (s.d. 0.73) and the mean time of postretention evaluation was 5.31 years (s.d. 1.61). The dental casts were measured at pretreatment (T1), posttreatment (T2) and postretention (T3), by the PAR index and by the Little irregularity index, and the correction due to treatment (T1-2) and the change at the postretention period (T3-2) were calculated. The descriptive statistics was performed and the Pearson correlation coefficient was applied for the PAR and the Little indices in the total sample, among the times evaluated. RESULTS: The mean PAR reduction due to treatment was 78.54%, and 66.6%, at the postretention stage related to pretreatment stage. Significant correlations were found for the PAR index at the times evaluated, except between T1 and T2 and between T1-2 and T3. In other words, the higher the treatment correction (T1-2), the lower the posttreatment PAR index (PAR T2) will be, and the higher will be the PAR change at the postretention period (PAR T3-2). Also, the higher the posttreatment PAR score (PAR T2), the higher will be the postretention PAR score (PAR T3). CONCLUSION: It was concluded that the quality of orthodontic treatment outcomes is not related to the long-term occlusal stability.OBJETIVO: O presente estudo objetivou analisar retrospectivamente casos com má oclusão de Classe I tratados com extrações dos quatro primeiros pré-molares, visando estabelecer a relação da qualidade dos resultados dos tratamentos ortodônticos e a estabilidade em longo prazo. MATERIAL E MÉTODOS: A amostra consistiu de 94 pacientes de ambos os gêneros, apresentando má oclusão de Classe I, tratados com extrações dos quatro primeiros pré-molares e mecânica Edgewise. Todos os pacientes selecionados eram leucodermas, sendo 50 do gênero masculino e 44 do feminino. A idade inicial média foi de 13.46 anos (d.p. 1.8). O tempo de tratamento médio foi 2.09 anos (d.p. 0.58), o tempo médio de contenção foi 1.63 anos (d.p. 0.73) e o tempo médio de avaliação pós-contenção, 5.31 anos (d.p.1.61). Foram medidos, nos modelos de estudo, o índice PAR e o índice de irregularidade de Little, nas fases pré (T1), pós-tratamento (T2) e pós-contenção (T3), e calculou-se a quantidade de correção com o tratamento (T1-2) e de alteração no período pós-contenção (T3-2). Realizou-se a estatística descritiva e o coeficiente de correlação de Pearson foi aplicado entre os índices estudados e os tempos avaliados. RESULTADOS: A média de redução do índice PAR da amostra total com o tratamento foi de 78.54%, e na fase pós-contenção, de 66.6%, com relação ao inicial. Houve correlação significante para o índice PAR nos tempos estudados, exceto entre T1 e T2 e entre T1-2 e T3. Ou seja, quanto maior a correção do tratamento (T1-2), menor será o índice PAR final (PAR T2), e maior a alteração no período pós-contenção (PAR T3-2). E quanto maior o índice PAR pós-tratamento (PAR T2), maior o índice PAR pós-contenção (PAR T3). CONCLUSÃO: Concluiu-se que a qualidade dos resultados dos tratamentos ortodônticos não está relacionada à estabilidade oclusal em longo prazo

Comparison between 3D volumetric rendering and multiplanar slices on the reliability of linear measurements on CBCT images: an in vitro study

OBJECTIVE: The purpose of this study was to determine the accuracy and reliability of two methods of measurements of linear distances (multiplanar 2D and tridimensional reconstruction 3D) obtained from cone-beam computed tomography (CBCT) with different voxel sizes. MATERIAL AND METHODS: Ten dry human mandibles were scanned at voxel sizes of 0.2 and 0.4 mm. Craniometric anatomical landmarks were identified twice by two independent operators on the multiplanar reconstructed and on volume rendering images that were generated by the software Dolphin®. Subsequently, physical measurements were performed using a digital caliper. Analysis of variance (ANOVA), intraclass correlation coefficient (ICC) and Bland-Altman were used for evaluating accuracy and reliability (

Influence of treatment with and without extractions on the growth pattern of dolichofacial patients

OBJECTIVE: The objective of this retrospective study was to compare, by means of lateral cephalograms, the facial growth pattern changes due to the treatment with and without extractions of four first premolars in dolichofacial individuals. METHODS: Groups 1 and 2 were constituted of 23 dolichofacial patients each, with Class II malocclusion, division 1 and initial age average of 12.36 and 12.29 years, respectively. Patients from Group 1 were treated without extractions and Group 2 was treated with extraction of the four first premolars, given that both used occipital headgear. Groups were compatibilized according to age, treatment period, gender and malocclusion severity. The t test was applied for intergroups comparison. RESULTS: Most variables (SN.PP, SN.Ocl and FMA) did not present statistically significant difference between groups. CONCLUSION: Although the treatment with extractions tend to reduce the mandibular plane angle (SN.GoGn) and the facial axis (NS.Gn), the analyzed treatment protocols did not affect in a clinically relevant way the facial growth pattern

A multidisciplinary approach for the management of hypodontia: case report

Hypodontia is the congenital absence of one or more teeth and may affect permanent teeth. Several options are indicated to treat hypodontia, including the maintenance of primary teeth or space redistribution for restorative treatment with partial adhesive bridges, tooth transplantation, and implants. However, a multidisciplinary approach is the most important requirement for the ideal treatment of hypodontia. This paper describes a multidisciplinary treatment plan for congenitally missing permanent mandibular second premolars involving orthodontics, implantology and prosthodontic specialties

Caracterização cefalométrica da má oclusão de Classe II, 1ª. divisão, em brasileiros leucodermas

One of the main points in Orthodontic studies is the growth and development of the craniofacial structures. In this study, skeletal cephalometric characteristics of Class II, division 1 malocclusion were assessed in lateral cephalograms. The experimental sample comprised 55 white Brazilian individuals of both genders, with an ANB angle of 4.5 degrees or higher. The mean age of the subjects was 13.5 years. Steiner and McNamara Jr cephalometric analyses were used in order to evaluate the relation between angular and linear positions of the apical bases, the dental and cranial structures, comparing with the values obtained in the control group (available at Bauru Dental School-USP). The results showed that, for the experimental group, the maxilla was well positioned in relation to the cranial base. The maxillomandibular relation showed an increased overjet, which was predictable based on criteria for sample selection. The geometrical proportion of the apical bases presented a small mandible and a normal sized maxilla. The craniofacial growth pattern presented a vertical tendency. The maxillary incisors were buccally inclined and well positioned by the linear evaluation. The mandibular incisors showed marked buccal inclination and protrusion. No statistically significant difference between genders was found.Um dos principais temas em Ortodontia é o estudo do crescimento e desenvolvimento craniofacial. Neste estudo, a caracterização cefalométrica da Classe II, 1ª divisão, esquelética, foi estudada em telerradiografias em norma lateral. O grupo experimental foi composto por 55 indivíduos brasileiros leucodermas, de ambos os gêneros, apresentando um ângulo ANB maior ou igual a 4.5 graus. A idade média foi 13.5 anos. Foram utilizadas grandezas cefalométricas da análise de Steiner e McNamara Jr. para avaliar a relação entre as posições angulares e lineares das bases apicais, estruturas dentárias e destas com as estruturas cranianas, comparando com os valores obtidos de um grupo controle (disponível na Faculdade de Odontologia de Bauru-USP). Os resultados mostraram que, no grupo experimental, a maxila apresentou-se bem posicionada em relação à base craniana. A relação maxilomandibular apresentou uma sobressaliência acentuada, o que já era previsível dado o critério de seleção da amostra experimental. A proporção geométrica entre as bases apicais apresentou a mandíbula de tamanho pequeno e a maxila normal. O padrão de crescimento craniofacial apresentou uma tendência vertical. Os incisivos superiores apresentaram-se inclinados para vestibular e bem posicionados pela avaliação linear. Os incisivos inferiores mostraram-se acentuadamente inclinados para vestibular e protruídos. Não houve diferença estatisticamente significante entre os gêneros

Estabilidade do tratamento de apinhamento anterossuperior

OBJECTIVE: To evaluate the stability and the relapse of maxillary anterior crowding treatment on cases with premolar extraction and evaluate the tendency of the teeth to return to their pretreatment position. METHODS: The experimental sample consisted of 70 patients of both sex with an initial Class I and Class II maloclusion and treated with first premolar extractions. The initial mean age was 13,08 years. Dental casts' measurements were obtained at three stages (pretreatment, posttreatment and posttreatment of 9 years on average) and the variables assessed were Little Irregularity Index, maxillary arch length and intercanine. Pearson correlation coefficient was used to know if some studied variable would have influence on the crowding in the three stages (LII1, LII2, LII3) and in each linear displacement of the Little irregularity index (A, B, C, D, E) in the initial and post-retention phases. RESULTS: The maxillary crowding relapse ( LII3-2) is influenced by the initial ( LII1), and the teeth tend to return to their pretreatment position. CONCLUSION: The results underline the attention that the orthodontist should be given to the maxillary anterior relapse, primarily on those teeth that are crowded before the treatment

Class II malocclusion treatment changes with the Jones jig, Distal jet and First Class appliances

Objective: Maxillary molar distalization with intraoral distalizer appliances is a non-extraction orthodontic treatment used to correct molar relationship in patients with Class II malocclusion presenting maxillary dentoalveolar protrusion and minor skeletal discrepancies. This study compares the changes caused by three distalizers with different force systems. Methodology: 71 patients, divided into three groups, were included. The Jones jig group (JJG, n=30; 16 male, 14 female, 13.17 years mean age) was treated with the Jones jig for 0.8 years. The Distal jet group (DJG, n=25; 8 male, 17 female, 12.57 years mean age) was treated with the Distal jet for 1.06 years. The First Class group (FCG, n=16; 6 male, 10 female, 12.84 years mean age) was treated with the First Class for 0.69 years. Intergroup treatment changes were compared using one-way ANOVA, followed by post-hoc Tukey’s tests. Results: Intergroup comparisons showed significantly greater maxillary incisor protrusion in DJG than in FCG (2.56±2.24 mm vs. 0.74±1.39mm, p=0.015). The maxillary first premolars showed progressive and significantly smaller mesial angulation in JJG, FCG and DJG, respectively (14.65±6.31º, 8.43±3.99º, 0.97±3.16º; p<0.001). They also showed greater mesialization in JJG than FCG (3.76±1.46 mm vs. 2.27±1.47 mm, p=0.010), and greater extrusion in DJG compared to JJG (0.90±0.77 mm vs 0.11±0.60 mm, p=0.004). The maxillary second premolars showed progressive and significantly smaller mesial angulation and mesialization in JJG, FCG and DJG, respectively (12.77±5.78º, 3.20±3.94º, -2.12±3.71º and 3.87±1.34 mm, 2.25±1.40 mm, 1.24±1.26 mm, respectively; p<0.001). DJG showed smaller distal angulation of maxillary first molars (-2.14±5.09º vs. -7.73±4.28º and -6.05±3.76º, for the JJG and FCG, respectively; p<0.001) and greater maxillary second molars extrusion (1.17±1.41 mm vs -0.02±1.16 mm and 0.16±1.40 mm, for the JJG and FCG, respectively; p=0.003). Overjet change was significantly larger in DJG compared to FCG (1.79±1.67 mm vs 0.68±0.84; p=0.046). Treatment time was smaller in FCG (0.69±0.22 years vs 0.81±0.33 years and 1.06±0.42 years, comparing it with the JJG and DJG, respectively; p=0.005). Conclusion: The three appliances corrected the Class II molar relationship by dentoalveolar changes. The Distal jet produced smaller molar distal angulation than the Jones jig and First Class. The First Class appliance showed less anchorage loss, greater percentage of distalization and shorter treatment time than the Jones jig and Distal jet