Abstract Horizontal bone loss after tooth extraction is a common finding that demands bone reconstruction in various cases. The aim of this study was to assess the horizontal alveolar status in partially and completely edentulous patients using cone-beam computed tomography (CBCT). In total, 1516 CBCT scans of 1404 adult patients were analyzed. Assessment of the images was performed in accordance with the previously published horizontal alveolar change (HAC) classification, which categorizes horizontal bone defects into four classes: HAC 1, HAC 2, HAC 3 and HAC 4 (from the least severe to the most severe condition). Analysis of 1048 scans from partially edentulous patients presented a distribution of 63.55%, 22.14%, 13.36% and 0.95% in HAC 1, HAC 2, HAC 3 and HAC 4, respectively. Analysis of 468 scans from completely edentulous patient images presented a distribution of 19.87%, 28.63%, 41.67% and 9.83% in HAC 1, HAC 2, HAC 3 and HAC 4, respectively. Based on these results, as in HAC 4, no cancellous bone was found between the cortical buccal and lingual/palatal bone plates, it seems reasonable to state that the absence of cancellous bone is higher in completely edentulous patients than in partially edentulous patients. Therefore, the absence of cancellous bone seems to be higher in completely edentulous than in partially edentulous patients.

Abstract: The lack of guidelines for bone augmentation procedures might compromise decision making in implantology. The objective of this study was to perform a retrospective study to verify the outcomes of horizontal bone reconstruction in implant dentistry with different types of materials and amounts of native bone in the recipient bed to allow for a new guideline for horizontal bone reconstruction. One hundred preoperative CT scans were retrospectively evaluated and categorized in accordance to horizontal bone defects as presence (Group P) or absence (Group A) of cancellous bone in the recipient bed. Different approaches were used to treat the edentulous ridge and the outcomes were defined either as satisfactory or unsatisfactory regarding the possibility of implant placement. The percentage distribution of the patients according to the presence or absence of cancellous bone was 92% for Group P and 8% for Group A. In Group P, 98% of the patients had satisfactory outcomes, and the use of autografts had 100% of satisfactory outcomes in this group. In Group A, 37.5% of the patients had satisfactory outcomes, and the use of autografts also yielded 100% of satisfactory outcomes. The use of allografts and xenografts in Group A had 0% and 33.3% of satisfactory outcomes, respectively. Therefore, it seems reasonable to speculate that the presence of cancellous bone might be predictive and predictable when the decision includes bone substitutes. In cases of absence of cancellous bone in the recipient bed, the use of a vitalized graft seems to be mandatory.

RESUMO Objetivo: avaliar, por meio do método dos elementos finitos, a distribuição das tensões no disco articular produzidas pela mentoneira ortopédica. Métodos: um modelo tridimensional simplificado do disco articular foi desenvolvido com o software Rhinoceros 3D e exportado para o software ANSYS. Uma carga de 4,9 N (500 gf) foi aplicada na superfície inferior do modelo, com inclinação de 30, 40 e 50o em relação ao plano mandibular Gônio-Mentoniano (GoMe). O ANSYS analisou, por meio do método dos elementos finitos, a distribuição das tensões presentes no modelo do disco articular para as diferentes angulações. Resultados: os resultados mostraram que a concentração das tensões de tração e compressão foi maior na superfície inferior do modelo. A tensão de tração foi mais presente na região média-anterior do modelo, e sua localização não se alterou nas três direções da aplicação da carga. A tensão de compressão foi mais presente nas regiões média e média-posterior do modelo, mas quando a carga a 50o foi aplicada, ela se concentrou na região média. As intensidades das tensões de tração e compressão diminuíram progressivamente à medida que a carga foi aplicada mais verticalmente. Conclusão: as tensões induzidas pela mentoneira ortopédica se localizaram principalmente na superfície inferior do modelo. As cargas com maior angulação em relação ao plano mandibular produziram uma distribuição de tensões com menor intensidade e uma concentração da tensão de compressão na região média do modelo. Um modelo tridimensional simplificado se mostrou útil na avaliação da distribuição das tensões no disco articular induzidas pela mentoneira ortopédica.

ABSTRACT Objective: To assess the distribution of stress produced on TMJ disc by chincup therapy, by means of the finite element method. Methods: a simplified three-dimensional TMJ disc model was developed by using Rhinoceros 3D software, and exported to ANSYS software. A 4.9N load was applied on the inferior surface of the model at inclinations of 30, 40, and 50 degrees to the mandibular plane (GoMe). ANSYS was used to analyze stress distribution on the TMJ disc for the different angulations, by means of finite element method. Results: The results showed that the tensile and compressive stresses concentrations were higher on the inferior surface of the model. More presence of tensile stress was found in the middle-anterior region of the model and its location was not altered in the three directions of load application. There was more presence of compressive stress in the middle and mid-posterior regions, but when a 50o inclined load was applied, concentration in the middle region was prevalent. Tensile and compressive stresses intensities progressively diminished as the load was more vertically applied. Conclusions: stress induced by the chincup therapy is mainly located on the inferior surface of the model. Loads at greater angles to the mandibular plane produced distribution of stresses with lower intensity and a concentration of compressive stresses in the middle region. The simplified three-dimensional model proved useful for assessing the distribution of stresses on the TMJ disc induced by the chincup therapy.

OBJETIVO: Avaliar a desadaptação marginal entre intermediário micro-unit e cilindro metálicos, variando a angulação dos implantes, com dois tipos de materiais e diferentes técnicas de moldagem. MÉTODO: Modelo com três implantes (um perpendicular ao plano horizontal e dois inclinados) usando intermediários micro-units. Uma barra mestre acoplada ao modelo serviu de situação controle para avaliar a adaptação dos vinte corpos de prova, feitas com estereomicroscópio óptico. RESULTADOS: A confiabilidade do avaliador foi avaliada com Índice de Correlação Intraclasse, obtendo 99,6% (ótimo). Houve diferença estatisticamente significante entre os grupos, e com o teste Mann-Whitney comparou-se os grupos aos pares para um resultado mais preciso. CONCLUSÃO: O grupo que apresentou melhor comportamento foi o de tray aberta e silicone por condensação. O de pior resultado, que foi preciso ser moldado diversas vezes, foi o de tray fechada e silicone por condensação.

OBJECTIVE: To evaluate the marginal misfit between intermediate and micro-unitmetal cylinder, by varying the angle of the implants, using two different types of material and different molding techniques. METHODS: A model was made with three implants (one perpendicular to the horizontal plane and two inclined) using micro-unit intermediates. A rod attached to the master model served as a control condition to evaluate the suitability of the twenty specimens, carried out with the help of an optical stereomicroscope (Pantec, Brazil; Materials Testing Laboratory, São Leopoldo Mandic, Campinas, São Paulo). RESULTS: Evaluator reliability was assessed using theIntraclass Correlation Coefficient, obtaining 99.6% (excellent). There were significant differences between groups, and the Mann-Whitney test compared groups in pairs for a more accurate result. CONCLUSION: The group which presented the best behavior was open tray and condensation silicone and the worst result, that needed to be cast several times, was closed tray and condensation silicone.

OBJETIVO: Avaliar a calibração da força de palpação digital, bem como determinar a variação intra-examinador e a força média aplicada por uma amostra composta de 56 profissionais que atuam na especialidade de disfunção temporomandibular e dor orofacial. MÉTODOS: Foi solicitado a cada participante que pressionasse o centro de uma balança digital, sem visualizar o display, o valor que acreditasse ser correspondente à 1,0 kg e, posteriormente, a 0,5 kg, recomendados pelo protocolo de exame físico do Eixo I do Consortium, the Research Diagnostic Criteria for Temporomandibular Disorders. Foram considerados calibrados aqueles que aplicassem a força correta, aceitando-se uma variação de 20% (entre 0,4 e 0,6 kg para o menor valor e 0,8 a 1.2 kg para o maior valor), em 4 das 5 aferições realizadas. Na análise dos dados foi utilizado o teste t de Student (p≤0,05). RESULTADOS: 70% da amostra foi classificada como não calibrada para a força de 0,5 kg e 57% não calibrada para 1,0 kg. A variação média intra-examinador de 0,3 kg para o peso de 0,5 kg e 0,6 kg para o de 1,0 kg foram consideradas altas. CONCLUSÃO: A força média aplicada pelos participantes (0,7 kg para palpação articular e 1.4 kg para palpação muscular) foi maior que o recomendado pelo Consortium, the Research Diagnostic Criteria for Temporomandibular Disorders, entretanto encontra-se de acordo com a tendência em aplicar valores mais altos entre 1,0 e 1,5 kg, validado em estudo recente.

OBJECTIVE: The present research aims to evaluate the calibration of digital palpation pressure as well as to assess the inter-examiner variation and mean pressure used by a sample consisting of 56 professionals of the TMJ disorders and Orofacial Pain area. METHODS: Each participant was asked to press a digital balance to approach 1.0 kg and subsequently 0.5 kg without seeing the display, in order to obtain a blind data. The values of 1.0 kg and 0.5 kg are recommended by the Research Diagnostic Criteria for Temporomandibular Disorder in the refined Axis I, the Physical Assessment. Participants were considered calibrated when they applied the correct pressure in at least 4 of the 5 measurement taken; within a 20% variation interval (pressures between 0.4 and 0.6 kg were acceptable for the reference value of 0.5 kg and between 0.8 and 1.2 kg for the reference value of 1.0kg). The t-student test was used to analyze data (p≤0.05). RESULTS: 70% of the sample was classified as non- calibrated for the 0.5 kg pressure while 57% were not calibrated for the 1.0 kg pressure. The mean inter-examiner variations, 0.3 kg for the pressure set at 0.5kg and 0.6 kg for the pressure set at 1.0 kg, were considered high. CONCLUSION: The mean pressures applied by participants (0.7 kg for joint palpation and 1.4 kg for muscle palpation) were also considered high in comparison with those recommended by the Research Diagnostic Criteria for Temporomandibular Disorder, but acceptable according to the tendency of applying higher values of 1.0 - 1.5 kg, as proven by recent study.

The aim of this study was to evaluate the accuracy of three implant transfer impression techniques. Four groups (n = 5) were defined, according to the technique: TC - tapered copings without splint; SC - square copings without splint; SCS - square copings splinted with dental floss and acrylic resin, and CG (control group) - master model with four external hexagonal implants and a superstructure. Individual trays and polyether were used for the impression. All casts were checked for their fit into the master superstructure; for this, all four screws were placed in the implants. Digital photos were taken and images were analyzed using UTHSCSA ImageTool software. Statistical analyses were performed using one-way analysis of variance and Student’s t test (p < 0.05). The means and standard deviation were (µm): CG = 2.03 ± 0.00, TC = 14.74 ± 3.41, SC = 12.08 ± 2.56, and SCS = 6.51 ± 0.09. The control group was found to be statistically different from the TC and SC groups. Within the limitations of this study, all groups presented clinically acceptable standard gap values, and the SCS group showed no statistical difference in relation to the CG (control group), demonstrating more accuracy and fidelity to transfer implants.

OBJETIVO: avaliar o padrão de desoclusão apresentado nos movimentos excursivos mandibulares e a presença ou não de interferências oclusais e patologias relacionadas à oclusão (recessão gengival e abfração). MÉTODO: exame de 120 indivíduos, divididos em 2 grupos: Grupo 1 - 90 pacientes com fissura completa de lábio e palato, subdivididos em 30 pacientes com fissura completa de lábio e palato unilateral esquerda, 30 pacientes com fissura completa de lábio e palato unilateral direita e 30 com fissura completa de lábio e palato bilateral; e Grupo 2 - 30 indivíduos sem fissuras (grupo controle). RESULTADOS: 58,8% do Grupo 1 apresentaram guia canina uni ou bilateralmente, 26,6% apresentaram desoclusão com função em grupo uni ou bilateral e 54,4% realizaram estes movimentos laterais através dos dentes posteriores; 80% dos pacientes do Grupo 1 realizava protrusão pelos dentes anteriores e 20 % pelos posteriores. Para o Grupo 2, guia canina uni ou bilateral foi observada em 69,6% dos indivíduos, 43,2% apresentaram função em grupo uni ou bilateral e somente 13,3% realizaram os movimentos laterais pelos dentes posteriores. Apenas 3,4% dos indivíduos do Grupo 2 apresentaram protrusão pelos dentes posteriores. CONCLUSÕES: não houve diferença estatisticamente significativa no padrão de desoclusão entre os subgrupos de pacientes com fissuras. O Grupo 2 apresentou predominância de função em grupo bilateral, enquanto o Grupo 1 apresentou maior prevalência de guia posterior durante os movimentos laterais. A protrusão ocorreu principalmente por guia anterior no Grupo 2 e pelos dentes posteriores no Grupo 1. Houve alta prevalência de interferências oclusais na região de molares para ambos os grupos, entretanto sem correlação com patologias oclusais (recessão e abfração).

OBJECTIVE: to analyze the pattern of disocclusion during excursive mandibular movements and presence or absence of occlusal interferences and occlusal pathologies (gingival recession and abfraction). METHOD: examination of 120 individuals divided into two groups, as follows: Group 1 - 90 patients with complete cleft lip and palate (study group), subdivided into 30 patients with complete left unilateral cleft lip and palate, 30 patients with complete right unilateral cleft lip and palate and 30 patients with complete bilateral cleft lip and palate; Group 2 - 30 individuals without clefts (control group). RESULTS: 58.8% of patients in Group 1 presented unilateral or bilateral canine guidance, 26.6% presented unilateral or bilateral group function and 54.4% presented lateral movements through the posterior teeth. Regarding protrusive movements, 80% presented anterior guidance and 20% presented posterior guidance. In Group 2, 69.6% of individuals presented unilateral or bilateral canine guidance, 43.2% presented unilateral or bilateral group function and only 13.3% presented lateral movements through the posterior teeth; 3.4% presented protrusion through the posterior teeth. CONCLUSIONS: there was no difference in the pattern of disocclusion between subgroups of patients with clefts. Group 2 presented predominance of bilateral group function, whereas Group 1 presented a higher prevalence of posterior guidance during lateral movements. Protrusion occurred primarily through anterior guidance in Group 2 and through the posterior teeth in Group 1. There was high prevalence of occlusal interferences at the molar area for both groups, yet with no correlation with occlusal pathologies (recession and abfraction).