Analysis of the influence of residual alveolar bone height on sinus augmentation outcomes

Introduction Maxillary sinus augmentation is a predictable implant site development technique for posterior atrophic maxillary ridges. However, graft consolidation requires adequate angiogenesis and migration of osteogenic cells from native bone. Therefore, the amount of residual bone height ( RBH ) may play a role in the rate of graft maturation. The purpose of this study was to analyze the influence of RBH in the histomorphometric outcomes of maxillary sinus augmentation procedures. Material and methods Patients in need of sinus augmentation were recruited for the study. Customized radiographic guides were fabricated and a cone‐beam computerized tomography scan was obtained at baseline. Two examiners measured RBH on the scans at the locations marked by the radiographic guide. Sinus grafting was performed by a lateral window approach using a particulated mineralized allograft. Patients were followed up for 6 months. At the time of implant placement, bone core biopsies were harvested using the radiographic guide, which was converted into a surgical guide. Samples were histomorphometrically analyzed. Proportion of vital bone (% VB ), remaining allograft particles (% RA ), and non‐mineralized tissue (% NMT ) were quantified. Categorical analysis of correlation of RBH (<4 or ≥4 mm) with% VB and% RA was performed using a statistical model. Results Twenty‐one patients underwent sinus augmentation for a total of 21 sinuses. One patient developed an infection after grafting and was excluded. Histomorphometric analysis revealed that mean% VB was 20.47 ± 18.25, mean % RA was 29.04 ± 24.94, and average % NMT was 50.47 ± 12.76. No significant correlation between RBH and % VB ( r  = 0.016; P  =   0.951), and RBH and % ( r  = 0.009; P  =   0.971) was found. Similarly, categorical analysis of correlation showed no statistical significance. Conclusion These findings suggest that the remaining alveolar bone height does not appear to influence the maturation and consolidation of an allograft in the maxillary sinus.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93580/1/clr2270.pd

A histomorphometric meta-analysis of sinus elevation with various grafting materials

Several grafting materials have been used in sinus augmentation procedures including autogenous bone, demineralized freeze-dried bone (DFDBA), hydroxyapatite, β-tricalcium phosphate (β-TCP), anorganic deproteinized bovine bone and combination of these and others. Up to now a subject of controversy in maxillofacial surgery and dentistry is, what is the most appropriate graft material for sinus floor augmentation

Avaliação do comportamento de quatro biomateriais associados a enxertos ósseos autógenos nos procedimentos cirúrgicos de elevação de seio maxilar. Estudo histomorfométrico em humanos

O objetivo deste trabalho foi estudar, histológica e histométricamente, o comportamento de enxertos ósseos e biomateriais, utilizados para aumento de altura óssea em cavidade sinusal de humanos. Para tanto, foram selecionados 20 pacientes e divididos em quatro grupos que após obtenção do material de enxerto da região de sínfise mentoniana, receberam o seguinte tratamento: Grupo GI, após elevação do assoalho da cavidade sinusal receberam associação de osso autógeno e osso desmineralizado, seco e congelado (Dembone), Grupo GII, receberam após elevação do assoalho da cavidade sinusal associação de osso autógeno e hidroxiapatita (Osteogen), Grupo GIII, receberam associação do osso autógeno e polímero vegetal osteintegrável (Poliquil), após elevação da cavidade sinusal e Grupo GIV, após elevação do assoalho do seio maxilar receberam associação do osso autógeno cimento de fosfato de cálcio (Bone Source). Os pacientes de cada condição experimental permaneceram, durante o período de 10 meses, sem receber carga mastigatória na região citada e após esse período, os pacientes receberam implantes osseointegrados, sendo nesse momento coletado material para exame histológico e histométrico. Os resultados mostraram que houve ganho de massa óssea em todos grupos, onde o osso novo formado, mostrou características habituais da região. Além disso as substâncias utilizadas apresentaram compatibilidade biológica, pois foram integradas total ou parcialmente aos tecidos ao longo do processo de regeneração óssea. Os resultados histométricos mostraram um índice médio de formação óssea de 60,86% para o Grupo GI, 54,29% para o Grupo GII, 38,50% para o Grupo GIII e 44,35% para o Grupo GIV, verificando-se diferenças entre os grupos de tratamento, no entanto não se pode apontar superioridade de um dos materiais.The aim of this study was to evaluate, by histological and histometric analysis, the behavior of the association of autogenous bone graft with biomaterials used in sinus lift procedures. Out of 20 patientes were used in this study, and they were equally distributed among 4 different groups: GI: Autogenous bone graft with DFDBA (Dembone); GII: Autogenous bone graft with hidroxilapatite (Osteogen); GIII: Autogenous bone graft with castor oil polimer (Poliquil); and GIV: Autogenous bone graft calcium phosphate cement (Bone Source). After the subantral augmentation was performed the autogenous bone graft was collected from the chin and associated with the biomaterial, according to the group the patient was previously located, and subantral cavity was filled. The groups were allowed to repair without load during 10 months. After this period biopsies were taken, during implant placement surgery for analysis. The results showed an improvement in bone area in all groups. The biomaterials were total or partial absorved thought out the bone regeneration process. The results of histomorfometrical analysis were GI 60,86%, GII 54,29%; GIII 38,50% and GIV 44,35%, in although there were differences among the groups none of the materials showed a better result when compared to another one

Insertion angle of orthodontic mini-implants and their biomechanical performance: finite element analysis

AbstractObjectiveThe aim of this study was to assess the stresses and strains generated after the application of two types of forces (traction of 200 gf and torsion of 20 N.cm) in two types of orthodontic mini-implants inserted at different (45° and 90° to the cortical bone) angles.Material and methodthree-dimensional models of two brands of mini-implant (SIN – Sao Paulo, Brazil, and RMO – South Korea) were exported and analyzed by finite element analysis (FEA). Analyses were performed on simulations of cortical bone, cancellous bone and the screw.ResultFEA analysis showed that RMO mini-implants had greater elastic deformation when subjected to tensile and torsional forces when compared with SIN mini-implants. For both trademarks and insertion angles tested, there was greater cortical bone deformation, but with the greatest strain located on the mini-implant. Tension on the mini-implant was located in its transmucosal profile region.ConclusionWhen comparing the two brands of mini-implants by FEA, it is fair to conclude that that the larger number of threads and their greater angle of inclination resulted in less resistance to deformation and induced a higher level of tension in the mini-implant and cortical bone when subjected to forces, especially when inserted at an angle of 45º to the cortical bone

Tratamento multidisciplinar: relato de casos clínicos

Introduction: Adult patients are more prone to periodontal disease mainly caused by poor plaque control. In these patients, orthodontic movement is not contraindicated, but it is necessary to evaluate their periodontal status so that we can establish the appropriate treatment plan. Objective: The objective of this article is to describe and discuss the clinical cases of severely periodontally compromised individuals in need of oral rehabilitation. Methods: The study consisted of orthodontic treatment of two cases with periodontal involvement. After clinical and radiographic examinations, the cases were analyzed by a multidisciplinary team of Orthodontics, Periodontics and Prosthodontics, in order to provide the patient with the best possible esthetic, functional and stability outcomes. Periodontal treatment consisted of supra and subgingival scaling prior to orthodontic treatment, and regular maintenance performed on a quarterly basis throughout orthodontic movement. Activation was carried out every 45 to 50 days, with light forces. Retention remains to the present day, even after completion of the rehabilitation. Conclusion: Multidisciplinary oral rehabilitation treatment yields satisfactory results. The interaction between Orthodontics and Periodontics reveals that patients with reduced, but healthy periodontium, can receive orthodontic treatment as long as the forces applied do not exceed patient's biological limits.Introdução: O paciente adulto apresenta maior predisposição para doença periodontal, decorrente, principalmente, do mal controle de placa. Nesses pacientes, a movimentação ortodôntica não é contraindicada, porém, é necessária uma avaliação da condição periodontal para que se possa estabelecer o plano de tratamento apropriado. Objetivo: Descrever e discutir casos clínicos de indivíduos com necessidade de reabilitação bucal e com periodonto severamente comprometido. Métodos: Os métodos consistiram no tratamento ortodôntico de dois casos com comprometimento periodontal. Após exames clínicos e radiográficos, os casos foram analisados de forma multidisciplinar, envolvendo as especialidades de Ortodontia, Periodontia e Prótese, com objetivo de proporcionar ao paciente os melhores resultados estético, funcional e estabilidade. O tratamento periodontal consistiu de raspagem supra- e subgengival, previamente ao tratamento ortodôntico, e programa de manutenção periódica trimestral durante toda movimentação ortodôntica. As ativações foram realizadas em intervalos de 45 a 50 dias, com a utilização de forças leves, sendo utilizadas contenções em ambas as arcadas, mesmo após a finalização da reabilitação. Conclusão: O tratamento reabilitador bucal, quando feito de forma multidisciplinar, traz resultados bastante satisfatórios. A interação da Ortodontia e da Periodontia comprovou que pacientes com periodonto reduzido, porém saudável, podem receber tratamento ortodôntico, desde que as forças não excedam o limite biológico desse