Estudio del espesor de la mucosa del trígono retromolar con el objetivo de facilitar la planificación de mini implantes en la región

The retromolar triangle is a triangular area located in the mandible, posteriorly to the last molar. This region, due its thickness and bone density, is widely used for the installation of devices that provide an anchorage system for the movement of the lower molars. The aim of this research is to provide morphometric data of the mucosa thickness of the retromolar triangle. Twenty-five patients of portuguese nationality, with indication for extraction of the impacted lower third molar (right and/or left), were studied. In the region of the retromolar triangle were demarcated 3 points corresponding to the vertices of a triangle whose the base was torned for the distal face of the lower third molar and the lenght of the sides corresponded to vestibulolingual dimension of the same tooth, then was demarcated a fourth point corresponding to the geometric center of the triangle. Then, using a finger spreader with silicone stop were measured the mucosal tickness at each point. The data obtained were tabulated and analyzed. The lowest average value found was 5.5mm on the right side and the highest average value found was 7.13mm on the left side. Considering the mean values obtained at the points of the retromolar triangle mucosa measured in this study, we conclude that the retromolar triangle shows thick mucosa, so the mini-implants indicated for this region should have a long transmucosal neck.

Técnica estrutural: confecção de pilar personalizado cerâmico para otimizar a estética

Na reabilitação protética com implantes, a reconstituição das características anatômicas do tecido peri-implantar é fundamental para a obtenção de uma estética ótima. Como os componentes metálicos não transmitem a luz, fazem com que os pacientes com fenótipos gengivais finos apresentem uma coloração escurecida, resultante da limitação estética desses componentes. Pilares cerâmicos (alumina ou zircônia) têm sido utilizados para resolver esse problema, os quais possibilitam a complementação com próteses metal free. A indústria fornece, para alguns sistemas, componentes pré-fabricados cerâmicos a serem personalizados por desgastes e componentes personalizados confeccionados com sistemas CAD/CAM e CAD/MAN. Tendo em vista as limitações de algumas das conexões desses componentes, o objetivo desse estudo é apresentar a técnica laboratorial para confecção de um pilar personalizado cerâmico realizado sobre pilar UCLA de sobrefundição. Concluiu-se que a utilização da cerâmica feldspática proporciona ótima estética, boa transparência, resistência mecânica, baixo custo, melhor capacidade adesiva, com utilização de cimentos resinosos, e, principalmente, técnica de amplo domínio dos laboratórios.

Aspectos biológico-celulares da osseointegração baseados nas superfícies de implantes

Osseointegration involves a cascade of biological events, which can be accelerated by modifying the micro and/or nanometric topography of dental implant surfaces. Considering that different treatment types modify the titanium surface giving it a more pronounced rough topography, and physicochemical changes that appear to positively influence the osseointegration process, a literature review was made on the main types of surface treatments and their influence on the biological and cellular aspects of osseointegration, with publications dating from 1969 until the present moment. Although the precise role of the implant surface on the osseointegration of dental implants is not completely clear, the specific effects of implant surface on bone regeneration, initial kinetics, and evolution of mechanical properties have shown to be quite promising. Thus, based on dental implant surface modifications, osseointegration can be defined as a process by which rigid asymptomatic fixation of an alloplastic material can be achieved and kept in close contact with bone tissue, being resistant to early and late functional loads. This process can be modulated by an appropriate treatment of the alloplastic material surface.

Estudo mecânico comparativo da estabilização de fratura ilíaca com dois tipos de implantes (parafusos com placa de compressão dinâmica e parafusos associados ao polimetilmetacrilato) em hemipelves caninas sintéticas

Pós-graduação em Cirurgia Veterinária - FCAV

Estudo das microdeformações geradas ao redor de implantes de hexágono externo, sob a aplicação de cargas axiais e não axiais em pilares protéticos retos e angulados

Pós-graduação em Odontologia Restauradora - ICT

Avaliação da resistência à fratura de próteses fixas temporárias reforçadas por uma malha experimental

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise in vitro da proliferação celular e produção de mediadores inflamatórios por células da conjuntiva estimuladas por materiais utilizados na confecção de próteses oculares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da água ozonizada e gluconato de clorexidina sobre propriedades mecânicas e microbiológicas de materiais utilizados para confecção de próteses odontológicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Contribuição ao estudo das relações dos conectores maiores de próteses parciais removíveis com tecidos gengivais

The effect in the gingival tissue of four distinctive types of relationships between the major conector and the gingival margin was investigated in eight subjects in association with the experimental gingivitis model. The subjects wore appliances constructed in acrylic resin (retained by means of embrasure hooks) throughout the day an night, except during meals. After the appliances had been placed, the subjects were abstained from any oral hygiene for twenty-one days. Records of the Plaque Index, Gingival Index and probing deplh were taken at baseline and at each week. Data showed that there was a small increase in the Plaque Index and Gingival Index for the four areas and that the degree of inflammation of the covered areas was higher in the area without relief

Regeneração óssea vertical usando barreira não-porosa de politetrafluoretileno em implantes osteointegrados inseridos parcialmente na tíbia de coelhos

The purpose of this study was to evaluate the possibility to obtaining guided bone regeneration utilizing a nonporous PTFE barrier in the osseointegrated implants, protruding from the bone level of the rabbit tíbia. The histologic characteristics of the interface between titanium implants, one group titanium-plasma coated, another group with acid-treated surfaces and the regenerated bone were also studied Twenty Screw-Vent implants were placed in tibias of five rabbits, two at the right side and two at the left side, protruding 3 mm from the bone level, to create a horizontal bone defect. ln the experimental side, the implants and adjacent bone were protected with a nonporous PTFE barrier. Histologic analysis after three months showed that all implants were in direct contact with the bane. Histologic measurements showed an average gain in bone height of the 2.15 and 2.42 mm for the barrier group and 1.95 and 0.43 mm for the control defects, in the titanium plasma-spray and acid-treated implant surfaces, respectively. The results suggest that the placement of implants protruding 3 mm from crestal bone defects may result in vertical bone augmentation and the regenerated bone is able to osseointegrate implants. lt seems to be critical the use of the PTFE barrier when acid-treated surface implants are inserted

O efeito do consumo abusivo de alvool no torque de remoção de implantes de titânio

Studies have reported that alcohol may lead to imbalance in bone formation and resorption, however, its effects on osseointegration of titanium implants continues to be an inconclusive subject. In this context, the aim of this study was to make a biomechanical evaluation of the effect of abusive alcohol consumption on the removal torque of osseointegrated titanium implants. Male Wistar rats (n=30) were divided into two experimental groups (15 each) receiving only water (Control) or 36% alcohol solution oral administration. Thirty days later, all animals were submitted to titanium implant (2.2 mm x 4 mm) placement in the right and left tibiae. The surgical alveoli were prepared with a 2 mm drill mounted in a counter-angle hand-piece (20:1 ratio, 35 Ncm torque at 1200 rpm) under abundant cooling. Five animals from each group were euthanized at 15, 30, and 60 days. Tibiae were submitted to reverse torque analysis. Data obtained were submitted to statistical analysis by the non-parametric Kruskal-Wallis and Dunn Tests (p < 0.05). Animals in the alcohol group presented lower removal torque values when compared with control group animals for all periods tested (p < 0.05). It can be concluded that abusive alcohol consumption can reduce the removal torque of titanium implants placed in rat tibiae, suggesting that alcohol may interfere in the osseointegration process of titanium implants.

Fatores biomecânicos relevantes na seleção dos grampos em próteses parciais removíveis com extremo livre: estudo clínico

The free-end removable partial dentures (RPD) shows a complicated and peculiar biomechanical behavior that impose high occlusion forces to the abutment teeth. By this way, the aim of this study was to evaluate the several factors that influence the clasps indication to free-end RPD. It was analysed 84 designed and planned study models of 71 patients, involving 130 clasps near-by a free-end; followed by clinical and radiographical informations. It was observed that bar clasps (“T”, “Tmod”, “i”) were used in 88.46% of abutment teeth. In the others (11.55%), it was used simple, combinated or ring circumferential clasps, and MDL. In abutment teeth with high equator line the “i” clasps were predominant (48.48%). The “Tmod” clasps were predominant in abutment teeth with low equator line (50%) or in middle third (51.35%) and “T” clasps were predominant in inclined equators with mesio-buccal (56.52%) or disto-buccal (66.66%) retention. In the posterior abutment teeth, it was prevalent the distal rest (63.52%) and embracing to the adjacent tooth. Some others factors like long clinical crown (5.38%), wrong position of abutment teeth (4.61%), aesthetics (3.07%), retention in alveolar ridge (2.3%), fragility of abutment teeth (1.53%), short clinical crown (0.76%) and short space to the clasp (0.76%) influenced directly during the clasps selection. Factors like mobility of abutment teeth, height of muscular insertions, depth of buccal fornix and antagonist arch acted like secondary factors. After the informations analysis it may be concluded that the bar clasps with distal rest and embracing to the adjacent tooth were the most indicated to free-end RPD