Prevalence of condylar morphological changes in individuals with class II malocclusion.

This observational, cross-sectional study with retrospective collection was aimed to evaluate the prevalence of morphological changes in mandibular condyles in individuals with class II malocclusion, classified according to different vertical growth patterns (brachyfacial, mesofacial, and dolichofacial), through cone beam computed tomography (CBCT). Seventy CBCT images (140 mandibular condyles) were selected from individuals without orthodontic treatment, of both sexes, aged between 25 and 50 years. No statistically significant differences were found between facial patterns; however, there was a higher relative prevalence of bone changes in dolichofacial individuals with flattening (62%), sclerosis (44%), and subchondral bone cyst (20%). Erosion and osteophytes prevailed in mesofacial (39%), and brachyfacial individuals (32%), respectively. Thus, there was no statistically significant difference in the prevalence of degenerative changes between the vertical skeletal patterns. Flattening was the most prevalent change, whereas subchondral bone cyst was the least prevalent among the three groups studied. The observational design of this study makes it possible to analyze image banks to verify the correlation of morphological changes in the temporomandibular joint in different facial patterns in patients with class II malocclusion. A limitation of the study is that clinical characteristics were not evaluated.

Craniomandibular transverse tomographic evaluation after anterior open bite orthodontic treatment with miniplates anchorage.

BACKGROUND: Skeletal anterior open bite (SAOB) represents one of the most complex and challenging malocclusions in orthodontics. Orthodontic treatment supported by miniplates enable to reduce the need for orthognathic surgery. Transverse dimension may be affected by intrusion biomechanics. This study aims to assess transverse bone alterations in patients with SAOB who underwent orthodontic treatment with absolute anchorage using four miniplates. METHODS: A total of 32 patients of both sexes, with an average age of 33.8 years, diagnosed with SAOB and treated orthodontically with four miniplates (one in each hemiarch), were selected for this study. Tomographic examinations were performed before (T1) and after (T2) orthodontic treatment. Linear measurements (width of the maxillary base, maxillary alveolar, maxillary root, maxillary dental cusp, mandibular alveolar) and angular measurements (maxillary intermolar angle) were assessed in these images. The Shapiro-Wilks normality tests were applied to verify data distribution, and the paired t-test was used to compare the initial and final measures obtained. RESULTS: Among the evaluated parameters, the maxillary alveolar width, maxillary dental cusp width, mandibular alveolar cusp width, and intermolar angle showed statistically significant differences between T1 and T2 (p < 0.05). However, maxillary base and maxillary root widths showed no significant difference (p > 0.05). CONCLUSIONS: Intrusion and distalization with miniplates in SAOB therapy may lead to significant expansive changes, due to molars cusps width and buccal inclination increase restricted at the alveolar level.

Definition of New Three-Dimensional Cephalometric Analysis of Maxillomandibular Sagittal Relationship for Orthodontics and Orthognathic Surgery: Normative Data Based on 700 CBCT Scans.

The objective of the study was to define the norm of new 3-dimensional cephalometric analysis of maxillomandibular sagittal relationship with the patient in Natural Head Position. A cross-sectional study was performed using 700 consecutives cone beam computed tomography datasets of pre-orthodontic patients received for three-dimensional craniofacial analysis. To stablish the clinical norm of the new sagittal reference (linear distance A-B), the correlation with the gold standard (ANB angle) was estimated with the Pearson's correlation coefficient. Subsequently, the prognostic values of the linear distance A-B was calculated to define the clinical norm. The sample was composed by 463 women (66.1%) and 237 men (33.9%). The mean age was 30 ± 14,5 years old (range 6-71 y old). According to the skeletal class classification (ANB), 46.1% (323) were class I, 42% (294) class II, and 11.9% (83) class III. The regression model found that each additional grade of the ANB angle imply a mean increase of 1.24 mm of the distance A-B ( P <0.001). The normative value of the linear distance A-B was obtained through the prognostic values of the distance for the limits of the ANB norm 0 to 4. These values were on the range of 0.52 to 5.48 mm. Therefore, the clinical norm for cephalometric maxillomandibular sagittal relationship using linear distance from point A-B is: 3±2.48 mm. With this new approach, we can define the skeletal sagittal relationship of the patient in natural head position overcoming the limitations of using intracranial or occlusal plane references improving the diagnosis and orthognathic surgical planning process.

Finite element analysis of a newly designed miniplate for orthodontic anchorage in the maxillary anterior region.

INTRODUCTION: Multiple force vector applications may be indicated when an arch segment or en masse intrusion is needed. This finite element method study aimed to evaluate the total deform the stress yielded in the bone and the miniplate when forces with different directions and magnitudes were applied. METHODS: First, the prototyped skull model was fabricated on the basis of computed tomography (CT) scans. On this model, the miniplate was fixed, and orthodontic appliances were attached. Then, a 3-dimensional finite element model was constructed by reproducing the characteristics of the physical model. Seven situations were investigated, which diverged in the point of force application, the direction and the number of force vectors, and the force magnitudes. RESULTS: When the force was applied at 1 point, similar behavior could be observed concerning the deformation and the stress in the miniplate, the maxilla, and the screw holes. Most deformation and stress appeared in the transmucosal arm below the step bend and at the force application point. The angled vectors (-45° and 30°) presented smaller values concerning the vertical vectors. Similar or better performances could be observed when the forces were simultaneously applied at the 2 points. CONCLUSIONS: The newly designed miniplate showed similar or improved performances when multiple vectors were applied at the 2 points simultaneously compared with the force applied at 1 point. This newly designed miniplate may present improved performance in a clinical situation when multiple forces are demanded.

Aesthetic perception of smile in long face pattern patients who underwent maxillary impaction with miniplates or orthognathic surgery.

INTRODUCTION: The gummy smile is perceived in 10% of the population aged 20 to 30 years old, and it causes an aesthetic imbalance in the smile. This study investigated the existence of differences in the aesthetic perception of the smile after correcting the gummy smile using two different techniques: orthognathic surgery for maxillary impaction and miniplate-aided orthodontic impaction. METHODS: Photographs of 16 Long Face Pattern female patients were evaluated by 56 oral and maxillofacial surgeons, 56 orthodontists, and 56 laypeople before and after the treatment with one of the two techniques. These photographs were standardized using the Photoshop program, randomly organized, and then presented to the evaluators via the Google Meeting® application in the PowerPoint® program. To evaluate the attractiveness of the smile, the Visual Analogue Scale (VAS) was used. To analyze the intra and inter-examiner concordances, Spearman's correlation and Kendall's concordance tests were used, respectively. For intergroup comparison, the Friedman test was used, with a 5% significance level. RESULTS: For all three groups of evaluators, the post-treatment evaluation results were superior to the results before the treatment: surgeons and orthodontists assigned higher scores for surgical cases and laypeople for orthodontic cases. CONCLUSION: From a clinical point of view, there was no difference between the results of both techniques with regard to the aesthetic perception of smiles. A gingival exposure ranging from zero to two millimeters was considered the most aesthetic for all evaluators.

Effect of orthodontic maxillary posterior en masse intrusion anchored with miniplates on maxillary sinuses volume. Retrospective CBCT study.

OBJECTIVE: To evaluate, by means of cone beam computed tomography (CBCT), the volume change of maxillary sinuses in patients that underwent orthodontic maxillary posterior en masse intrusion anchored with miniplates. MATERIALS AND METHODS: The sample consisted of pretreatment (T1) and posttreatment (T2) CBCT scans obtained from 14 patients (4 male and 10 female), with a mean age of 32.4 years, that underwent orthodontic maxillary posterior en masse intrusion anchored with miniplates in the zygomatic crest. The mean treatment duration was 20 months and the mean intrusion movement was 2.4 mm. Maxillary sinus volume was measured by means of the software ITK SNAP (version 3.8.0) in T1 and T2 CBCT scans. The changes in sinuses volume were calculated by T1-T2 values. Data were analyzed statistically with Wilcoxon test at 5% of level of significance and the method error was analyzed with Wilcoxon test, intraclass correlation and Dahlberg's formula. RESULTS: The mean difference (T1-T2) was -242.85 mm³ (p = 0.396) for the right sinus and -32.5 mm³ (p = 0.875) for the left sinus. A slight increase in the volume of the sinuses was shown although these results were not statistically significant. CONCLUSION: The orthodontic maxillary posterior en masse intrusion anchored with miniplates did not influence significantly the maxillary sinus volume.

Negligible tooth resorptions after anterior open bite treatment using skeletal anchorage with miniplates.

INTRODUCTION: When miniplates are used as anchoring for orthodontic mechanics for anterior open bite correction by retraction of anterior teeth and posterior teeth intrusion and retraction, orthodontically induced inflammatory external apical root resorption is clinically negligible. METHODS: A homogeneous sample of 32 patients was used, and the roots of the teeth were compared on CT scans performed before and after orthodontic treatment. RESULTS: The observed root resorption was minimal, and this can be explained by the uniform distribution of forces in several teeth, simultaneously, in the set of the dental arch and in the bone that supports the teeth. CONCLUSION: The most important thing to prevent root resorption in orthodontic practice, besides being concerned with the intensity of the applied forces, is to be careful with its distribution along the roots of each tooth, in the dental arch and in the bone that supports the teeth.

Negligible tooth resorptions after anterior open bite treatment using skeletal anchorage with miniplates

ABSTRACT Introduction: When miniplates are used as anchoring for orthodontic mechanics for anterior open bite correction by retraction of anterior teeth and posterior teeth intrusion and retraction, orthodontically induced inflammatory external apical root resorption is clinically negligible. Methods: A homogeneous sample of 32 patients was used, and the roots of the teeth were compared on CT scans performed before and after orthodontic treatment. Results: The observed root resorption was minimal, and this can be explained by the uniform distribution of forces in several teeth, simultaneously, in the set of the dental arch and in the bone that supports the teeth. Conclusion: The most important thing to prevent root resorption in orthodontic practice, besides being concerned with the intensity of the applied forces, is to be careful with its distribution along the roots of each tooth, in the dental arch and in the bone that supports the teeth.

RESUMO Introdução: Quando são utilizadas miniplacas como ancoragem para a mecânica ortodôntica de correção da mordida aberta anterior por meio da retração dos dentes anteriores e intrusão e retração dos dentes posteriores, as reabsorções radiculares apicais externas inflamatórias induzidas ortodonticamente são clinicamente irrelevantes. Métodos: Usou-se uma amostra homogênea de 32 pacientes, e comparou-se as raízes dos dentes em tomografias realizadas antes e depois do tratamento ortodôntico. Resultados: As reabsorções radiculares observadas foram mínimas, e isso pode ser explicado pela distribuição uniforme das forças em vários dentes, simultaneamente, no conjunto da arcada dentária e no osso que suporta os dentes. Conclusão: O mais importante para se prevenir as reabsorções radiculares na prática ortodôntica, além de se preocupar com a intensidade das forças aplicadas, é tomar cuidado com a sua distribuição ao longo das raízes de cada dente, na arcada dentária e no osso que suporta os dentes.

Correção da classe III esquelética em pacientes jovens - ertty gap III® / Correction of skeletal class III in young patientes - ertty gap IIII®

As más oclusões de Classe III são consideradas desafiadoras no tratamento ortodôntico, por apresentarem um componente genético forte. O retrognatismo maxilar, o prognatismo mandibular e a combinação dessas discrepâncias caracterizam os problemas esqueléticos. A terapia ortodôntica mais recomendada, usualmente, para o tratamento da Classe III em fase de crescimento é a protração maxilar, associada ou não à disjunção da sutura palatina mediana. Vem sendo muito considerada, também, uma técnica com auxílio de miniplacas. Entretanto existem desvantagens nessas técnicas, quanto à colaboração do paciente, à possível instabilidade na fixação das miniplacas devido à faixa etária, dentre outras considerações que estimularam o desenvolvimento de outro sistema para o tratamento da Classe III em pacientes jovens, o Ertty Gap III®. O objetivo desse artigo foi apresentar essa nova forma de tratamento da Classe III em indivíduos jovens. O novo sistema é composto, na dentição mista, por um Hyrax invertido na arcada superior, Placa Lábio Ativa e Barra Lingual Fundida na arcada inferior e por elástico de Classe III. Em casos de dentadura permanente, o elástico de Classe III é colocado no bráquete do canino inferior. Foi alcançado um excelente resultado clínico no caso ilustrado, pois se obteve melhora no perfil facial, correção dentoalveolar da Classe III e redirecionamento do crescimento maxilomandibular. Sendo assim, o Ertty Gap III® é uma técnica viável de ser aplicada. Além disso, é um sistema estético de baixo custo e apresenta uma mecânica ortopédica e/ou ortodôntica simples, que o torna de fácil entendimento e domínio profissional durante sua aplicação (AU)

Class III malocclusions are considered challenging in orthodontic treatment, because they present a strong genetic component. Maxillary retrognathism, mandibular prognathism and the combination of these discrepancies characterize skeletal problems. The most commonly recommended orthodontic therapy for the treatment of Class III in the growth phase is maxillary protraction, associated or not with the disjunction of the medial palatine suture. A technique with the aid of miniplates has also been greatly considered. However, there are drawbacks in these techniques, such as patient collaboration, possible instability in fixation of miniplates due to age, among other considerations that stimulated the development of another system for the treatment of Class III in young patients, the Ertty Gap III® . The aim of this article was to present this new form of Class III treatment in young individuals. The new system is composed, in the mixed dentition, by an inverted Hyrax in the upper arch, a Lip-Active Plate and a Fused Lingual Bar in the lower arch and by Class III elastic. In cases of permanent dentures, the Class III elastic is placed in the lower canine bracket. An excellent clinical result was achieved in the clinical case presented, as improvement in the facial profile, dentoalveolar Class III correction and redirection of the maxillomandibular growth were obtained. Therefore the Ertty Gap III® is a viable technique to be applied. In addition, it is an aesthetic system with low cost, and it presents simple orthopedic and/or orthodontic mechanics, which makes it easy for both understanding and professional domain during its application.(AU)

Ortodontia, Cirurgia e Estética: a importância da abordagem multidisciplinar / Orthodontics, Surgery and Cosmetic Dentistry: the importance a multidisciplinary approach

Introdução: a má oclusão de Classe II é caracterizada por um inadequado relacionamento maxilomandibular anteroposterior. Essa má oclusão maxilar e/ou mandibular pode ter origem esquelética e/ou dentoalveolar. Para corrigir a má oclusão esquelética de Classe II com retrognatismo mandibular em pacientes adultos, é necessária a realização de cirurgia ortognática, além do tratamento ortodôntico. Assimetrias dentárias, quando associadas a essa má oclusão, devem ser corrigidas no preparo ortodôntico pré-cirúrgico. Objetivo: apresentar um novo método de preparo ortocirúrgico ilustrado por um caso clínico de paciente com má oclusão de Classe II esquelética com retrognatismo mandibular, associada a assimetria dentária inferior. Métodos: miniplacas de titânio foram usadas como ancoragem temporária para obter maior controle durante a movimentação dos dentes nas arcadas dentárias. Resultados: a assimetria dentária inferior foi facilmente corrigida com a mecânica utilizada, em curto período de tempo e sem efeitos colaterais indesejados. Subsequentemente, o avanço mandibular e a mentoplastia foram realizados cirurgicamente. Após a finalização ortodôntica, executou-se a reanatomização dentária. Conclusão: esse caso clínico demonstra a importância das miniplacas e da abordagem multidisciplinar (Ortodontia, Cirurgia e Odontologia Estética) para obter sucesso no resultado final do tratamento.