Three-dimensional evaluation of dental decompensation and mandibular symphysis remodeling on orthodontic-surgical treatment of Class III malocclusion.

INTRODUCTION: The purposes of this research were to identify the buccolingual inclinations of the mandibular teeth and the mandibular symphysis remodeling that result from the orthodontic decompensation movement. METHODS: The sample consisted of 30 adults with Class III dentofacial deformity, who had presurgical orthodontic treatment. Three-dimensional images were generated by cone-beam computed tomography scans at 2 different times (initial and before orthognathic surgery). Three-dimensional virtual models were obtained and superimposed using automated voxel-based registration at the mandible to evaluate B-point displacement, mandibular molar and incisor decompensation movement, and symphysis inclination and thickness. The 3-dimensional displacements of landmarks at the symphysis were quantified and visualized with color-coded maps using 3D Slicer (version 4.0; www.slicer.org) software. RESULTS: The measurements showed high reproducibility. The patients presented mandibular incisor proclination, which was consistent with the movement of tooth decompensation caused by the presurgical orthodontic treatment. Statistically significant correlations were found between the inclination of the mandibular incisors, symphysis inclination, and B-point displacement. Regarding the thickness of the symphysis and the inclination of the incisors, no statistically significant correlation was found. CONCLUSIONS: The buccolingual orthodontic movement of the mandibular incisors with presurgical leveling is correlated with the inclination of the mandibular symphysis and repositioning of the B-point but not correlated to the thickness of the symphysis.

Correlation between buccolingual tooth inclination and alveolar bone thickness in subjects with Class III dentofacial deformities.

INTRODUCTION: The purposes of this study were to identify buccolingual inclinations and alveolar bone thickness in patients with Class III dentofacial deformities and to compare these measurements with those from subjects with normal occlusions to verify, based on the correlation between these 2 variables, whether the natural process of bone remodeling provides uniformity of bone thickness or whether it varies around the roots due to tooth inclination. METHODS: The sample consisted of 35 adults with normal occlusions and 35 adults with Class III dentofacial deformities with no previous orthodontic treatment. Buccolingual inclinations and alveolar bone thickness were measured at 3 heights from the cementoenamel junction from 3-dimensional images generated by cone-beam computed tomography. RESULTS: The region corresponding to the maxillary canines appeared to be thinner, and the palatal area of the maxillary central incisors and the distobuccal region of the mandibular second molars appeared to be thicker. Greater tooth inclinations were observed in the maxillary incisors and mandibular canines, and smaller tooth inclinations were observed on the buccal roots of the mandibular second molars. CONCLUSIONS: In subjects with Class III deformities, more statistically significant correlations were found between inclination and thickness in the mandibular teeth, whereas in subjects with normal occlusion, few statistically significant correlations were found between these 2 variables.

Oral focal mucinosis associated with surgically assisted rapid maxillary expansion.

Oral focal mucinosis is a rare soft-tissue lesion that might result from the overproduction of hyaluronic acid by fibroblasts. The lesions are commonly found on the gingiva and palate; however, other sites, such as the tongue, have also been reported. The diagnosis of oral focal mucinosis is based on histologic analysis, and treatment involves surgical excision. Recurrences of lesions have not been reported. This article presents a patient with oral focal mucinosis that might be associated with surgically assisted rapid maxillary expansion.

Micro-osteoperforation effectiveness on tooth movement rate and impact on oral health related quality of life.

OBJECTIVES: To investigate the effect of micro-osteoperforation (MOP) on the rate of tooth movement (RTM), space closure duration, and oral health-related quality of life (OHRQoL) during completion of anterior retraction in patients undergoing combined orthodontic-surgical treatment after premolar extraction and decompensation with sliding mechanics. MATERIALS AND METHODS: Twenty-four participants with indications for premolar extractions were randomly allocated to treatment with conventional sliding mechanics (control group; CG) or with to treatment in which three MOPs were performed every activation (experimental group; EG). Dental impressions were taken monthly until space closure was completed and dental casts were converted to three-dimensional models. After the anterior retraction procedure, Oral Health Impact Profile (OHIP-14) questionnaires were filled out at 4 and 72 hours. RESULTS: Eighteen patients (7 men and 11 women) remained in the trial until space closure was completed (mean follow-up period = 247 days). For full space closure RTM, no significant difference (P = .492) was found between groups (0.614 mm/month for the CG; 0.672 mm/month for the EG). The RTM for different time points, groups, time frames and their interaction were statistically different (P < .05). In multiple correlation analysis, the RTM significantly decreased over time for both groups (P < .05). The OHRQoL scores were significantly higher (worse) for the EG. The psychological, physical and social disabilities, and handicap domains displayed significant differences between the two groups. CONCLUSION: Use of MOPs did not change the full space closure RTM, while it had a negative impact on OHRQoL.

Effect of orthodontic treatment on alveolar bone thickness in adults: a systematic review.

OBJECTIVES: This review aimed at evaluating changes in alveolar bone thickness after completion of orthodontic treatment. METHODS: Only prospective clinical studies that reported bone thickness in adult patients undergoing non-surgical orthodontic treatment were considered eligible. MEDLINE, EMBASE and LILACS databases were searched for articles published up to July 2018. RESULTS: A total of 12 studies met the selected criteria. Most of the studies showed that orthodontic treatment produces a reduction in bone thickness of incisors, mainly at the palatal side. CONCLUSION: On patients undergoing different orthodontic treatment techniques, there was a significant bone thickness reduction, mainly on the palatal side. CLINICAL RELEVANCE: These findings are relevant and have to be considered in diagnosis and planning of tooth movement, in order to prevent the occurrence of dehiscence and fenestration in alveolar bone.

Periodontal clinical evaluation before and after surgically assisted rapid maxillary expansion.

INTRODUCTION: The surgically assisted rapid maxillary expansion is a procedure that reduces the resistance of the sutures correcting the posterior crossbite in adults. OBJECTIVE: The aim of this study was to evaluate the periodontal status of 17 adults submitted to this procedure. METHODS: The clinical attachment level (CAL), gingival recession, attached gingiva and bleeding were evaluated in maxillary first premolars and molars, central and lateral incisors of right and left sides before surgery, 5 days and 6 months after. Means, standard deviation, medians, minimum and maximum values were compared among the evaluations using the Friedman and McNemar tests. RESULTS: There was a statistically significant increase in CAL in the right central incisor, right and left premolars and right and left molars. There was a statistically significant increase in gingival recession in the right and left premolars and molars. The amount of attached gingiva significantly decreased in right premolars and right and left molars. There was increase in bleeding in most of the teeth. CONCLUSION: Results indicated that the surgically assisted rapid maxillary expansion might cause alterations in periodontal tissue.

Periodontal clinical evaluation before and after surgically assisted rapid maxillary expansion

ABSTRACT Introduction: The surgically assisted rapid maxillary expansion is a procedure that reduces the resistance of the sutures correcting the posterior crossbite in adults. Objective: The aim of this study was to evaluate the periodontal status of 17 adults submitted to this procedure. Methods: The clinical attachment level (CAL), gingival recession, attached gingiva and bleeding were evaluated in maxillary first premolars and molars, central and lateral incisors of right and left sides before surgery, 5 days and 6 months after. Means, standard deviation, medians, minimum and maximum values were compared among the evaluations using the Friedman and McNemar tests. Results: There was a statistically significant increase in CAL in the right central incisor, right and left premolars and right and left molars. There was a statistically significant increase in gingival recession in the right and left premolars and molars. The amount of attached gingiva significantly decreased in right premolars and right and left molars. There was increase in bleeding in most of the teeth. Conclusion: Results indicated that the surgically assisted rapid maxillary expansion might cause alterations in periodontal tissue.

RESUMO Introdução: a expansão rápida da maxila assistida cirurgicamente (ERMAC) é um procedimento que reduz a resistência das suturas, corrigindo a mordida cruzada posterior em adultos. Objetivo: o objetivo deste estudo foi avaliar o status periodontal de 17 adultos submetidos a esse procedimento. Métodos: o nível clínico de inserção (NCI), a recessão gengival, gengiva inserida e sangramento foram avaliados nos primeiros pré-molares, molares, incisivos centrais e laterais superiores dos lados direito e esquerdo antes da cirurgia, e depois de 5 dias e 6 meses. Médias, desvios-padrão, medianas, valores mínimos e máximos foram comparados entre as avaliações, usando os testes de Friedman e McNemar. Resultados: houve aumento estatisticamente significativo no NCI no incisivo central direito, pré-molares direito e esquerdo e molares direito e esquerdo. Houve aumento estatisticamente significativo na recessão gengival nos pré-molares e nos molares direito e esquerdo. A quantidade de gengiva inserida diminuiu significativamente nos pré-molares direitos e molares direitos e esquerdos. Houve aumento no sangramento na maioria dos dentes. Conclusão: os resultados indicaram que a ERMAC pode causar alterações no tecido periodontal.

Avaliação tridimensional da descompensação dentária e remodelação óssea pré-cirúrgica nas más oclusões de classe III / Tridimensional evaluation of presurgical orthodontic decompensation and bone remodeling in subjects with class III dentofacial deformity

Esta pesquisa foi realizada com o objetivo de identificar as inclinações dentárias vestíbulo-linguais dos dentes inferiores e as características morfológicas da sínfise mandibular decorrentes do movimento de descompensação dentária. A amostra constituiu-se de 30 indivíduos adultos, com deformidade dentofacial de classe III, submetidos ao tratamento ortodôntico pré-cirúrgico. A partir de imagens tridimensionais geradas por exames de tomografia computadorizada de feixe cônico, em dois tempos distintos (inicial e previamente à realização da cirurgia ortognática) foram obtidos modelos virtuais tridimensionais, que foram sobrepostos por meio do registro pelo voxel na base do crânio e na mandíbula, para avaliação da direção e quantidade de rotação mandibular, deslocamento do mento, deslocamento do ponto B, movimento de descompensação dentária dos incisivos e molares inferiores e inclinação e espessura da sínfise mandibular. Os deslocamentos tridimensionais de pontos de referência na sínfise foram quantificados e visualizados por mapas codificados por cores e sobreposições semitransparentes por meio do programa SlicerCMF 3-1® versão 4.5.0. O teste de Correlação de Pearson foi utilizado para verificar a correlação entre inclinação dentária, espessura, inclinação da sínfise e deslocamento do ponto B. As espessuras e inclinações médias da sínfise foram comparadas entre os tempos inicial e pré-cirúrgico com uso de testes t-Student pareado. As medidas apresentaram alta reprodutibilidade. A maioria dos pacientes apresentou rotação horária da mandíbula e deslocamento do mento no sentido posterior e inferior. O ponto B se movimentou no sentido posterior e superior. Além disso, os incisivos inferiores apresentaram vestibularização, que foi condizente com o movimento de descompensação dentária originado pelo preparo pré-cirúrgico. Foram encontradas correlações estatisticamente significativas entre a inclinação dos incisivos inferiores e as medidas de inclinação da sínfise e deslocamento do ponto B. Com relação à espessura da sínfise e a inclinação dos incisivos, não foi encontrada correlação estatisticamente significante. Em relação à comparação entre os tempos estudados, não foram encontradas diferenças estatisticamente significantes.

Efeitos da rotação da cabeça sobre as imagens fotográficas em norma frontal / Effects of head rotation on frontal photographic images

O objetivo deste estudo foi avaliar as diferenças das dimensões faciais nos lados direito e esquerdo a partir de fotografias frontais obtidas com diferentes graus de rotação da cabeça. Foram utilizadas 22 fotografias de adultos em cujas faces foram de marcados os pontos: sobrancelha, subnasal, pogônio, Dl e D2, B1 e B2. Uma máquinaYashica Dental Eye III foi posicionada sobre um tripé com o longo eixo da objetiva paralela ao solo. Adaptou-se no cefalostato um marcador para que as fotografias do mesmo indivíduo pudessem ser obtidas nas angulações O", 1,5", 3,0° e 5,0°. Foram demarcadas nas fotografias quatro regiões (A 1, A2, A3 e A4) e cada uma foi comparada à sua correspondente nas quatro angulações estudadas. Por meio da análise estatística foram obtidas as medidas de tendência central e dispersão. Observou-se que a medida que aumenta a rotação da cabeça para esquerda a área correspondente a hemiface direita sofre aumento, enquanto a hemiface esquerda apresenta redução. Concluiu-se que as rotações de 1,5", 3,0° e 5,0° produziram nas áreas AI e A2, alterações dimensionais de 4,2%, 5,9% e 9,8% e nas áreas A3 e A4, alterações dimensionais de 4,8%, 9,4% e 14,7%.

The purpose of this study was evaluate the dlflerences in dimensions on right and lefr sides of the face from frontalphotographs obtained with various degrees of head rotation. Fronta lphotographs of 22 adults were used and in each one was marked out the following points: eyebrow, subnasal, pogonion, D1 and 0 2 , BI and B2. A Yashica Dental Eye III camera was positioned on a tripod with the long a i s of the objective parallel to the ground. On the cephalostat was positioned a protractor so the photographs of the same individual could be obtained in 0º, 1,5º; 3,0º and 5,0° degrees. On the photographs, four regions (AI, A2, A3 e A4) were marked out and each one was compared to your correspondent on the ,four angulations. Statistical analysis was made and the measures of central trend and dispersion were obtained. It was observed that when the head rotation to the letl increases, the area corresponding to the right side of the face enlarges and the left side of the face decreases. It was concluded that rotations of 1,5°, 3,0° and 5,0° degrees produced on areas AI and A2 dimensional alterations of 4,2%, 5,9% and 9,8% and on areas A3 and A4 dimensional alterations of 4.8%, 9,4% and 14,7%.