Distalizador First Class modificado para ancoragem em mini-implantes

FAPESP 2009/04843-7, 2011/17126-1

Alternativa protética para correção da angulação com componentes não indexados sobre implantes Cone Morse indexados: sistema tubo parafuso

From a recent perspective the morse-taper dental implants connections are increasingly being used as an alternative for replacement of a missing teeth. Nevertheless, there are a large variety of prosthetic components available on the market with some limitations regarding the final prothesis. This article demonstrated the difficulties and limitations of prosthesis implant-retained connections when using morse-taper implants (with a prosthetic index) case in which the surgical placement of the implant wasn’t successfully performed. The alternative to overcome this scenario was the technique using the tube screw over the top of a mini abutment component. It was possible to manufacture and to have satisfactory adaptation, achieving the satisfaction of the patient, restoring function and esthetics.

Influence of miniscrew dental root proximity on its degree of late stability

Purpose of this study was to evaluate the influence of miniscrew dental root proximity on its late stability degree. 40 miniscrews were inserted between maxillary second premolars and first molars for anterior retraction. Post-surgical radiographs were used to measure the septum width in the insertion site, insertion height, distal and mesial distance from miniscrew to dental root, and the smallest distance between miniscrew and dental root. The miniscrews were divided in two groups according to septum width: ?3 mm (20 miniscrews) and >3 mm (20 miniscrews). The soft tissue in the insertion site, sensitivity during load, plaque around the miniscrew, and evaluation period were also considered. The results showed no significant difference in miniscrew mobility degree and success rate between groups. Miniscrew dental root proximity did not influence the stability and success rate when the distance between the miniscrew and dental root indicated no periodontal ligament invasion. The overall success rate was 90% and no variable was associated with miniscrew failure. Nevertheless, patient sensitivity was frequently associated with some degree of mini-implant mobility. The septum width did not influence the stability and success rate of this anchorage system, but the extreme root proximity did.

Influência do preparo do orifício piloto na ancoragem dos parafusos pediculares

OBJETIVO: Avaliamos a influência do diâmetro e do modo de preparação do orifício piloto na resistência ao arrancamento e no torque de inserção dos parafusos pediculares com diâmetro interno cônico. MÉTODOS: Ensaios mecânicos foram realizados com parafusos pediculares com alma cônica e diâmetro de 4,2mm e 5,2mm inseridos nos pedículos vertebrais lombares de suínos. O orifício piloto foi confeccionado com de broca e sondas (pontiaguda e cortante) com diferentes diâmetros. RESULTADOS: Testando o parafuso de 4,2mm a perfuração com orifício igual ou inferior ao menor diâmetro interno do parafuso, aumentou o torque e a resistência ao arrancamento. Perfurações com diferentes instrumentos apresentaram comportamento semelhante. Perfurações com sondas permitiram que orifícios confeccionados com dimensões superiores ao menor diâmetro interno do parafuso apresentassem resistência semelhante a das perfurações com dimensões iguais ao menor diâmetro interno do implante, realizadas com sondas e brocas. CONCLUSÕES: Nos de 4,2 mm o diâmetro e o modo de preparação do orifício influenciam o torque e a resistência, nos de 5,2 mm apenas o torque de inserção. Não há correlação entre força de arrancamento e torque de inserção. Nível de evidência II, Estudos terapêuticos - Investigação dos Resultados do Tratamento.

Fixação zigomática em portadores de fissura de lábio e palato: relato de caso clínico

A técnica de Fixação Zigomática serve como um meio alternativo para pacientes que apresentam grande perda de estrutura maxilar decorrentes de atrofia maxilar severa, traumas, cirurgias ressectivas tumorais ou defeitos congênitos. Pacientes portadores de fissura de lábio e palato podem ser beneficiados com esta técnica, pois apresentam baixo desenvolvimento de seus maxilares devido às cirurgias primárias de queiloplastia e palatoplastia. O implante zigomático de titânio que possui em média 30 mm a 52,5 mm de comprimento, se insere no rebordo alveolar remanescente em direção ao corpo do zigoma. Por meio dessa técnica, é possível ancorar uma prótese fixa utilizando carga precoce. Objetivo: O objetivo deste trabalho foi de relatar um caso ocorrido no Hospital de Reabilitação de Anomalias Craniofaciais, Bauru, São Paulo, com resolução protética de um paciente portador de fissura labiopalatina através da ancoragem zigomática. Relato Clínico: Em 2008, paciente do Hospital de Reabilitação de Anomalias Craniofaciais, portadora de fissura labiopalatina, foi realizado um planejamento criterioso e a opção mais adequada foi a resolução protética através de uma ancoragem em zigoma. Foi utilizado implante zigomático do lado direito e implantes unitários na região dos dos elementos dentários 13 e 11, após exodontia do elemento 11. Assim, confeccionada uma prótese sobre implantes e placa miorrelaxante com controle de 45 dias. Conclusão: Esta alternativa possibilita ao paciente uma menor morbidade, sem a necessidade de cirurgias de reconstrução óssea, apresenta um tempo menor de tratamento e consequentemente integrando o paciente à sociedade.

Avaliação da mucosa sinusal do coelho à presença de implante biodegradável

Pensando em melhorar a qualidade de vida dos pacientes com doenças do humor vítreo, os oftalmologistas começaram a utilizar recentemente implantes biodegradáveis com corticoide. Estes mesmos implantes podem ser uma alternativa no tratamento da RSC e, para isso, realizamos um estudo experimental em seios maxilares de coelhos. OBJETIVO: Avaliar histologicamente a mucosa de seio maxilar de coelhos após a colocação de implante biodegradável de prednisolona. MÉTODO: Dezoito coelhos foram divididos aleatoriamente em dois grupos: Grupo 1: no seio maxilar esquerdo foi inserido um implante biodegradável com prednisolona; Grupo 2: No seio maxilar esquerdo foi inserido um implante biodegradável sem medicação. Os seios maxilares do lado direito serviram como controle. Após 7, 14 e 28 dias foram escolhidos aleatoriamente três coelhos de cada grupo e a resposta tecidual inflamatória foi avaliada. RESULTADOS: Foi encontrada diferença não significativa de inflamação na mucosa, quando comparamos o grupo de coelhos que receberam implantes com e sem medicação com o grupo controle; ou quando comparamos o grupo que recebeu implante com prednisolona com o grupo que recebeu implante sem medicação. CONCLUSÃO: Não foram observados sinais de toxicidade ou inflamação na mucosa do seio maxilar do coelho à presença do implante com ou sem prednisolona.

Detorque evaluation of dental abutment screws after immersion in a fluoridated artificial saliva solution

Purpose: Implant-abutment connections still present failures in the oral cavity due to the loosening of mechanical integrity by detorque and corrosion of the abutment screws. The objective of this study was to evaluate the detorque of dental abutment screws before and after immersion in fluoridated solutions. Materials and Methods: Five commercial implant-abutment assemblies were assessed in this investigation: (C) Conex˜aoR , (E) EmfilsR , (I) INPR , (S) SINR , and (T) Titanium FixR . The implants were embedded in an acrylic resin and then placed in a holding device. The abutments were first connected to the implants and torqued to 20Ncmusing a handheld torque meter. The detorque values of the abutments were evaluated after 10 minutes. After applying a second torque of 20 Ncm, implant-abutment assemblies were withdrawn every 3 hours for 12 hours in a fluoridated solution over a period of 90 days. After that period, detorque of the abutments was examined. Scanning electronicmicroscopy (SEM) associated to energy dispersive spectroscopy (EDS) was applied to inspect the surfaces of abutments. Results: Detorque values of systems C, E, and I immersed in the fluoridated solution were significantly higher than those of the initial detorque. ANOVA demonstrated no significant differences in detorque values between designs S and T. Signs of localized corrosion could not be detected by SEM although chemical analysis by EDS showed the presence of elements involved in corrosive processes. Conclusion: An increase of detorque values recorded on abutments after immersion in fluoridated artificial saliva solutions was noticed in this study. Regarding chemical analysis, such an increase of detorque can result from a corrosion layer formed between metallic surfaces at static contact in the implant-abutment joint during immersion in the fluoridated solutions.

Rehabilitative treatment of cleft lip and palate: experience of the Hospital for Rehabilitation of Craniofacial Anomalies/USP (HRAC/USP) – part 4

Treatment of patients with cleft lip and palate is completed with fixed prostheses, removable, total, implants and aims to restore aesthetics, phonetics and function and should be guided by the basic principles of oral rehabilitation, such as physiology, stability, aesthetics, hygiene and the expectations of the patient. In order to obtain longevity of a prosthetic rehabilitation, the periodontal and dental tissue as well as the biomechanics of the prosthesis are to be respected. The purpose of this article is to describe the types of prosthetics treatment, which are performed at HRAC/USP for the rehabilitation of cleft area in adult patients.

Intraoral distalizer effects with conventional and skeletal Anchorage: a meta-analysis

Introduction: The aims of this meta-analysis were to quantify and to compare the amounts of distalization and anchorage loss of conventional and skeletal anchorage methods in the correction of Class II malocclusion with intraoral distalizers. Methods: The literature was searched through 5 electronic databases, and inclusion criteria were applied. Articles that presented pretreatment and posttreatment cephalometric values were preferred. Quality assessments of the studies were performed. The averages and standard deviations of molar and premolar effects were extracted from the studies to perform a meta-analysis. Results: After applying the inclusion and exclusion criteria, 40 studies were included in the systematic review. After the quality analysis, 2 articles were classified as high quality, 27 as medium quality, and 11 as low quality. For the meta-analysis, 6 studies were included, and they showed average molar distalization amounts of 3.34 mm with conventional anchorage and 5.10 mm with skeletal anchorage. The meta-analysis of premolar movement showed estimates of combined effects of 2.30 mm (mesialization) in studies with conventional anchorage and 4.01 mm (distalization) in studies with skeletal anchorage. Conclusions: There was scientific evidence that both anchorage systems are effective for distalization; however, with skeletal anchorage, there was no anchorage loss when direct anchorage was used.

Planejamento reverso em próteses totais implanto suportadas com carga imediata

The main objective of this paper was to discuss the importance of the reverse planning as guidance to surgical procedures on immediate loading implant-retained prosthesis, presenting a case report. Such design aims to define anchorage orientation after determination of prosthetic design. This is quite important because the possibility of success of cases with this kind of planning may achieve high levels of satisfaction. Another important aspect is the possibility of fast and definitive restoration of patients’ function and aesthetics

Effect of framework soldering on the deformation of implant abutments after framework seating: a study with strain gauges

Introduction: Passive fit has been considered an important requirement for the longevity of implant-supported prostheses. Among the different steps of prostheses construction, casting is a feature that can influence the precision of fit and consequently the uniformity of possible deformation among abutments upon the framework connection. Purpose: This study aimed at evaluating the deformation of abutments after the connection of frameworks either cast in one piece or after soldering. Materials and Methods: A master model was used to simulate a human mandible with 5 implants. Ten frameworks were fabricated on cast models and divided into 2 groups. Strain gauges were attached to the mesial and distal sides of the abutments to capture their deformation after the framework’s screw retentions were tightened to the abutments. Results: The mean values of deformation were submitted to a 3-way analysis of variance that revealed significant differences between procedures and the abutment side. The results showed that none of the frameworks presented a complete passive fit. Conclusion: The soldering procedure led to a better although uneven distribution of compression strains on the abutments.

The impact of healing time before loading on orthodontic mini-implant stability: a histomophometric study in minipigs

Objective: To evaluate healing time before loading, areas compression and tension and location of insertion on mini-implant stability. Design: Six minipigs were used. Each animal received 3 mini-implants in each quadrant: 1 mini-implant was used as an unloaded control (G1, n = 24); the other 2 were loaded with 150 g-force at three time intervals (G2: immediate loading, G3: after 15 days and G4: after 30 days), with 16 mini-implant in each experimental group. After 120 days, tissue blocks of the areas of interest were harvested. Clinical analysis (exact Fisher test) determined the survival rate. Histological analysis (Kontron KS 300TM, Zeiss) quantified the fractional bone-toimplant contact (%BIC) and bone area (%BA) at each healing time point, areas of interest, and insertion site (ANOVA and t tests for dependent and independent samples). Results: The mini-implant survival rates were G1: 71%, G2: 50%, G3: 75% and G4: 63%, with no statistical differences between them. The groups presented similar %BIC and %BA. There were no differences between the compression and tension sides or maxillary and mandibular insertion sites. Conclusions: These results suggest that low-intensity immediate or early orthodontic loading does not affect mini-implant stability, because similar histomorphometric results were observed for all the groups, with partial osseointegration of the mini-implants present.

Estabilidade em longo prazo do tratamento da má oclusão de classe II, divisão 1, com a utilização de um aparelho funcional propulsor mandibular fixo: relato de caso

O tratamento da má oclusão de Classe II sem extrações dentárias vem ganhando popularidade na comunidade ortodôntica já há três décadas. Aparelhos funcionais fixos vêm sendo utilizados por profissionais, de maneira crescente, para promover compensações dentoalveolares e corrigir a má oclusão de Classe II. Os efeitos mais significativos são observados em pacientes com padrão de crescimento horizontal. Um caso clínico será relatado com o uso do aparelho fixo Twin Force Bite Corrector em uma paciente do sexo feminino, para a correção da Classe II. Esse dispositivo de ancoragem fixa dispensa o uso de aparelhos funcionais removíveis e não necessita da cooperação do paciente.

Aesthetic analysis of an implant-supported denture at the cleft area

Objective: To evaluate the aesthetics of an implant-supported denture at the cleft area, comparing the peri-implant tissues and prosthetic crown with the contralateral tooth. Settings: Hospital for Rehabilitation of Craniofacial Anomalies, Bauru, São Paolo, Brazil. Patients: A total of 39 individuals of both genders, with complete unilateral cleft lip and palate, who received secondary alveolar bone graft and were rehabilitated with single implant-supported dentures at the area of the missing maxillary lateral incisor after completion of orthodontic treatment. Interventions: The following parameters were analyzed in follow-up sessions: length and width of prosthetic crown and contralateral tooth, characteristics of implants, filling of interproximal space by the papilla, and smile height of the patients. Results: The implant-supported prosthetic crowns were longer than the contralateral tooth (p < .001). Among the 78 papillae analyzed, 29 (37.17%) received a score of 3; 32 (41.02%) papillae had a score of 2; and 17 (21.79%) received a score of 1. Concerning the smile height, among the 39 patients analyzed, 23 (56.41%) had a medium smile, 15 (38.46%) had a high smile, and two (5.12%) presented a low smile. Conclusion: The use of dental implants to rehabilitate the edentulous cleft area is an excellent option. However, adequate evaluation of the bone quantity and quality, positioning and shape of adjacent teeth, smile height, and patient expectations should be considered to achieve success and avoid aesthetic deformities such as elongated teeth and absence of gingival papillae.