The Effects of Annual Maintenance on Peri-implant Health in Patients Rehabilitated with Overdentures: A Retrospective Cohort Study.

PURPOSE: The aim of this retrospective cohort study was to assess the effects of annual maintenance over a 7-year period on the peri-implant health of patients rehabilitated with overdentures using clinical and radiographic parameters. MATERIALS AND METHODS: In order to be considered for inclusion in the study, patients had to have been rehabilitated with overdentures that had at least two implants placed in the mandible and four implants in the maxilla. Patients were divided into two groups: group 1 comprised individuals who had undergone annual maintenance over the previous 7 years, and group 2 comprised those who had not attended any dental appointment over the previous 7 years. All patients were submitted to clinical peri-implant examinations and radiographic assessments. RESULTS: Sixty-six patients received 396 implants of the external hexagon type, 132 in the mandible and 264 in the maxilla. Group 1 (44 patients with 264 implants) had a mean probing depth of 2.72 mm, while group 2 (22 patients with 132 implants) had a mean probing depth of 3.10 mm. It can be concluded that the mean of the variable probing depth is influenced by the presence of bleeding (P = .0005) and the implementation of maintenance (P = .0188), whereas plaque and local variables were not otherwise significant (P = .0605 and .0796, respectively). CONCLUSION: In this study, it was possible to observe better clinical conditions in individuals who had attended annual appointments for maintenance purposes.

Comparison Of Full-Mouth Scaling and Quadrant-Wise Scaling in the Treatment of Adult Chronic Periodontitis.

In the search for the ideal treatment of periodontal disease various non-surgical techniques should be considered. The objective of this study was to evaluate the efficacy of full-mouth scaling (FMS) by clinical and microbiological parameters. 670 individuals were evaluated with 230 subjects meeting the selection criteria and were divided into two groups; 115 subjects treated with FMS and 115 treated with weekly sessions of scaling and root planning (SRP). The patient population had a mean age of 51.67 years, with moderate chronic periodontitis. Subjects were evaluated prior to treatment (T1) and 90 days after execution of therapy (T2), with regards to: probing depth (PD), clinical attachment level (CAL), plaque index (PI), gingival index (GI), and microbial detection for the presence of Porphyromonas gingivalis (P.g.) and Prevotella intermedia (P.i.) by culture method and confirmed by biochemical tests. Subjects treated in the FMS group also rinsed with 0.12% chlorhexidine mouthwash for seven days following treatment. The results were analyzed using statistical Student's t-test and chi-square test. No statistically significant differences were observed for PD and CAL between T1 and T2 in both groups. For GI and PI significant difference was observed between the groups. For the evaluated microbial parameters was observed reduction of P.g. and P.i., but only for P.g. with a significant reduction in both groups. The full mouth scaling technique with the methodology used in this study provided improved clinical conditions and reduction of P.g. in subjects with moderate periodontitis, optimizing the time spent in the therapeutic execution.

Comparison of full-mouth scaling and quadrant-wise scaling in the treatment of adult chronic periodontitis

Abstract In the search for the ideal treatment of periodontal disease various non-surgical techniques should be considered. The objective of this study was to evaluate the efficacy of full-mouth scaling (FMS) by clinical and microbiological parameters. 670 individuals were evaluated with 230 subjects meeting the selection criteria and were divided into two groups; 115 subjects treated with FMS and 115 treated with weekly sessions of scaling and root planning (SRP). The patient population had a mean age of 51.67 years, with moderate chronic periodontitis. Subjects were evaluated prior to treatment (T1) and 90 days after execution of therapy (T2), with regards to: probing depth (PD), clinical attachment level (CAL), plaque index (PI), gingival index (GI), and microbial detection for the presence of Porphyromonas gingivalis (P.g.) and Prevotella intermedia (P.i.) by culture method and confirmed by biochemical tests. Subjects treated in the FMS group also rinsed with 0.12% chlorhexidine mouthwash for seven days following treatment. The results were analyzed using statistical Student's t-test and chi-square test. No statistically significant differences were observed for PD and CAL between T1 and T2 in both groups. For GI and PI significant difference was observed between the groups. For the evaluated microbial parameters was observed reduction of P.g. and P.i., but only for P.g. with a significant reduction in both groups. The full mouth scaling technique with the methodology used in this study provided improved clinical conditions and reduction of P.g. in subjects with moderate periodontitis, optimizing the time spent in the therapeutic execution.

Resumo Na busca do tratamento ideal da doença periodontal varias são técnicas não-cirúrgicas que podem ser consideradas. O objetivo deste estudo foi avaliar a eficácia da técnica de desinfecção total de boca (FMD, na sigla em Inglês) por parâmetros clínicos e microbiológicos. Foram avaliados 670 indivíduos com 230 indivíduos atendendo aos critérios de seleção e divididos em dois grupos; 115 indivíduos tratados com FMD e 115 tratados com sessões semanais de raspagem e alisamento corono radicular (SRP, na sigla em Inglês). A população avaliada tinha idade média de 51,67 anos, com periodontite crônica moderada. Os sujeitos foram avaliados antes do tratamento (T1) e 90 dias após a execução da terapia (T2), quanto à profundidade de sondagem (PS), nível de inserção clínica (NIC), índice de placa (IP), índice gengival (IG) e detecção microbiana da presença de Porphyromonas gingivalis (P.g.) e Prevotella intermedia (P.i.) por método de cultura e confirmada por testes bioquímicos. Os indivíduos tratados no grupo FMD também realizaram bochechos com clorexidina 0,12% durante sete dias após o tratamento. Os resultados foram analisados ​​utilizando o teste estatístico t de Student e o teste de qui-quadrado. Não foram observadas diferenças estatisticamente significativas para PS e NIC entre T1 e T2 em ambos os grupos. Para IG e IP observou-se diferença significativa entre os grupos. Para os parâmetros microbianos avaliados foi observada redução de P.g. e P.i., mas apenas para P.g. com uma redução significativa em ambos os grupos. A técnica FMD com a metodologia utilizada neste estudo proporcionou condições clínicas melhoradas e redução da P.g. Em indivíduos com periodontite moderada, otimizando o tempo gasto na execução terapêutica.

Técnicas de transposição/lateralização do nervo alveolar inferior ­ uma revisão da literatura sobre o déficit neurossensorial e a taxa de sucesso dos implantes dentários / Transposition/lateralization techniques for the inferior alveolar nerve ­ a literature review on the neurosensorial and dental implant success rates

Objetivo: comparar as técnicas de lateralização (LNAI) e transposição do nervo alveolar inferior (TNAI) com a taxa de disfunção neurossensorial, bem como a taxa de sucesso dos implantes dentários. Material e métodos: uma pesquisa foi realizada no período de 1987 a 2016, no banco de dados Medline/PubMed, com as palavras-chave "implantes dentários", "nervo alveolar inferior", "lateralização", "transposição", "neurossensorial" e "taxa de sucesso". Foram incluídos artigos retrospectivos e prospectivos em seres humanos, e que apresentassem relatos de disfunção neurossensorial e taxa de sucesso dos implantes dentários na região posterior da mandíbula, após procedimentos de lateralização ou transposição do nervo alveolar. Resultados: dos 142 artigos encontrados na primeira fase de seleção, apenas 26 foram incluídos na técnica LNAI, com um total de 524 procedimentos, sendo 228 na técnica de TNAI e 296 na LNAI, que foram incluídos neste estudo. O número de implantes instalados pela técnica de TNAI foi de 625, e pela técnica de LNAI foi de 401. As técnicas de TNAI apresentaram um índice inicial maior de disfunção neurossensorial, quando comparadas à técnica de LNAI. A taxa de sucesso dos implantes para a té cnica de TNAI ficou entre 80% e 100%, e para a té cnica de LNAI fi cou entre 90,5% e 100%. Conclusão: a LNAI vem sendo uma boa indicação para a reabilitação de mandíbulas atróficas verticalmente, e sua execução com o piezo diminui o risco de distúrbio sensorial. As altas taxas de sucesso dos implantes podem ser atribuídas à possibilidade da instalação de implantes longos com ancoragem bicortical, favorecendo a estabilidade primária e a biomecânica.

Objective: to compare lateralization techniques (LNAI) and transposition of the inferior alveolar nerve (TNAI) with the rate of sensorineural dysfunction, as well as the success rate of dental implants. Material and methods: a survey was carried out between 1987 and 2016 in the Medline/PubMed database, with the key words "dental implants", "inferior alveolar nerve", "lateralization", "transposition", "neurosensorial", "success rate". Retrospective and prospective articles in humans that presented reports of sensorineural dysfunction and success rate of dental implants in the posterior region of the mandible after procedures of lateralization or transposition of the alveolar nerve were included. Results: in the fi rst phase of the selection, 142 articles were retrieved, but only 26 articles on LNAI, with a total of 524 procedures, 228 on TNAI technique and 296 the LNAI, were included in the study. The number of implants installed by the TNAI technique was 625 and by the LNAI 401. The TNAI present a higher initial index of sensorineural dysfunction than the LNAI and the success rate of the implants was for the TNAI between 80% to 100%, and for the LNAI between 90.5% and 100%. Conclusion: LNAI has been a good indication for the rehabilitation of atrophic mandibles vertically and its execution with piezo reduces the risk of sensory disturbance. The high success rates of implants can be attributed to the possibility of installing long implants with bicortical anchoring favoring primary stability and biomechanics.

Mini-Implant Screws for Bone-Borne Anchorage: A Biomechanical In Vitro Study Comparing Three Diameters.

PURPOSE: To evaluate the maximum strength and the maximum aperture supported by mini-implant screws of three different diameters in an in vitro rapid maxillary expander model. MATERIALS AND METHODS: Fifteen appliances were mounted in artificial bone polyurethane blocks. In each appliance, a Hyrax expander anchored by four mini-implant screw sets of three different diameters were divided into: group 1 (n = 5), 1.8-mm-diameter screws; group 2 (n = 5), 2.0-mm-diameter screws; and group 3 (n = 5), 2.2-mm-diameter screws. All sets (bone blocks + expander + four mini-implants) were inserted into a customized and standardized device that simulated a mid-palate disjunction. The expanders were activated to mechanically test the insertion of the mini-implant into the devices until breakage or deflection of screws occurred. The number of activations, the maximum supported strength, and the maximum expander aperture values until failure were recorded for each group. Data were subjected to a Student t test at a significance level of 5%. RESULTS: There were no significant differences between the groups regarding the number of activations up to the maximum supported strength. The expander achieved aperture values where differences were slightly significant just between groups 1 and 2 (P = .048). There was a significant difference between groups 1 and 3 regarding the maximum supported load (P = .039). CONCLUSION: Regardless of the mini-implant screw diameters, the expander device used in this anchorage system model withstood strengths and aperture rates beyond those that may be required during clinical rapid maxillary expansion.

Lateralization Technique and Inferior Alveolar Nerve Transposition.

Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics.

Manual reduction of articular disc after traumatic extraction of mandibular third molar: a case report.

INTRODUCTION: Disc displacement without reduction with limited opening is an intracapsular biomechanical disorder involving the condyle-disc complex. With the mouth closed, the disc is in an anterior position in relation to the condylar head and does not reduce with mouth opening. This disorder is associated with persistent limited mandibular opening. CASE REPORT: The patient presented severe limitation to fully open the mouth, interfering in her ability to eat. Clinical examination also revealed maximum assisted jaw opening (passive stretch) with less than 40 mm of maximum interincisal opening. Magnetic resonance imaging was the method of choice to identify the temporomandibular disorders. CONCLUSION: By means of reporting this rare case of anterior disc displacement without reduction with limited opening, after traumatic extraction of a mandibular third molar, in which manual reduction of temporomandibular joint articular disc was performed, it was possible to prove that this technique is effective in the prompt restoration of mandibular movements.

Manual reduction of articular disc after traumatic extraction of mandibular third molar: a case report

Introduction: Disc displacement without reduction with limited opening is an intracapsular biomechanical disorder involving the condyle-disc complex. With the mouth closed, the disc is in an anterior position in relation to the condylar head and does not reduce with mouth opening. This disorder is associated with persistent limited mandibular opening.Case report:The patient presented severe limitation to fully open the mouth, interfering in her ability to eat. Clinical examination also revealed maximum assisted jaw opening (passive stretch) with less than 40 mm of maximum interincisal opening. Magnetic resonance imaging was the method of choice to identify the temporomandibular disorders.Conclusion: By means of reporting this rare case of anterior disc displacement without reduction with limited opening, after traumatic extraction of a mandibular third molar, in which manual reduction of temporomandibular joint articular disc was performed, it was possible to prove that this technique is effective in the prompt restoration of mandibular movements.

Introdução: o deslocamento do disco articular sem redução com abertura limitada é uma desordem intracapsular que envolve o complexo côndilo-disco. Na posição de boca fechada, o disco articular se encontra numa posição anterior em relação à cabeça da mandíbula e não sofre redução com a abertura de boca. Essa desordem está associada à abertura mandibular limitada e persistente.Caso clínico:o paciente relatava travamento da mandíbula que não permitia uma abertura completa da boca, interferindo, assim, na capacidade de se alimentar. Também era possível observar-se uma abertura assistida (alongamento passivo) com uma distância vertical menor que 40 mm entre os incisivos. A ressonância magnética foi o método de escolha para o diagnóstico das desordens temporomandibulares.Conclusão:por meio da descrição de um caso raro de deslocamento anterior do disco articular sem redução e com abertura limitada, após exodontia traumática do terceiro molar inferior, em que foi realizada a redução manual do disco articular da articulação temporomandibular, provou-se ser essa uma técnica eficaz no rápido restabelecimento dos movimentos mandibulares.

Photoelastic Analysis on Different Retention Methods of Implant-Supported Prosthesis.

The aim of this study was to evaluate the stress distribution of different retention systems (screwed, cemented, and mixed) in 5-unit implant-supported fixed partial dentures through the photoelasticity method. Twenty standardized titanium suprastructures were manufactured, of which 5 were screw retained, 5 were cement retained, and 10 were mixed (with an alternating sequence of abutments), each supported by 5 external hexagon (4.0 mm × 11.5 mm) implants. A circular polariscope was used, and an axial compressive load of 100 N was applied on a universal testing machine. The results were photographed and qualitatively analyzed. We observed the formation of isochromatic fringes as a result of the stresses generated around the implant after installation of the different suprastructures and after the application of a compressive axial load of 100 N. We conclude that a lack of passive adaptation was observed in all suprastructures with the formation of low-magnitude stress in some implants. When cemented and mixed suprastructures were subjected to a compressive load, they displayed lower levels of stress distribution and lower intensity fringes compared to the screwed prosthesis.

Stress Analysis on Single Cobalt/Chrome Prosthesis With a 15-mm Cantilever Placed Over 10/13/15-mm-length Implants: A Simulated Photoelastic Model Study.

The aim of study was to assess the stress around 10/13/15-mm implants in the mandibular area with a 15-mm cantilevered acrylic-resin-coated prostheses following the application force, using the photoelasticity method. Three photoelastic mandibular models were created containing 10-, 13-, and 15-mm implants in length and 3.75 mm in diameter. The implants had bore internal hex connections and were placed parallel to the intermental region. Abutments with 1-mm high cuffs were placed over the implants, and a single cobalt/chrome metallic prosthesis with a 15-mm cantilever, coated with thermoplastic acrylic resin, was placed on top. Loads of 1.0 and 3.0 bars were applied, and the images were photographed and assessed by photoelasticity method. The greatest stress levels were observed for the 10-mm implants. The stress pattern was the same regardless of implant length; only the magnitude of the stress along the implant body revealed changes. Increased implant length played a role in reducing stress on the investigated area of the model, and the 15-mm implants exhibited the best performance in regard to stress distribution. The highest stress levels were found in the implants closest to the cantilever and the central implant. The longest implants were more favorable in regard to the stress distribution on the peri-implant support structures in the 15-mm cantilevered prosthesis under loads.

In vivo effectiveness of silicone gel sheets as barriers at the inner microgap between a prosthetic abutment and an external-hexagon implant platform.

PURPOSE: Bacterial penetration and colonization of the microgap at the implant-abutment interface have been reported in several studies. The aim of this study was to evaluate the effectiveness of placing a silicone membrane between the abutment and the implant platform in an attempt to seal the interface. MATERIALS AND METHODS: A total of 15 external-hex implants were placed in 10 patients with clinically healthy peri-implant tissues, and all of the patients had ceramic prosthetic crowns. Samples were collected from the microgaps before, 30 days after, and 90 days after insertion of a silicone membrane. Bacterial DNA was extracted and submitted in triplicate to polymerase chain reaction using primers specific for four peri-implant pathogens: Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia. RESULTS: In the initial samples, a positivity of 52% was found, which was different from that found in samples collected after 30 days (32%) and 90 days (27%) after insertion of the membrane. CONCLUSION: It was evident that the silicone membrane reduced, but did not prevent, penetration of these species into external-hex implants.

Fatores determinantes para formação e, ou manutenção da papila peri-implantar: revisão de literatura / Factors for formation and, or maintenance of peri implant papilla: literature review

Introdução: a papila interproximal, entre outros requisitos, é considerada fundamental para o sucesso estético nas próteses sobre implantes. Método: o presente artigo é uma revisão da literatura baseada em periódicos publicados de 1984 a 2011, disponíveis nos bancos de dados da LILACS e da MEDLINE. Foram selecionados 21 artigos com o objetivo de evidenciar os fatores determinantes para formação e/ou manutenção da papila peri-implantar, tais como distância ideal entre dente e implante, entre implantes, sua posição supra ou infraóssea e a distância necessária do ponto de contato à crista óssea. Conclusão: concluiu-se que a distância ideal entre dente e implante é de 2mm, e a entre implantes é de 3mm, haja vista que a altura da papila gengival é sustentada pela formação do espaço biológico. Quanto ao posicionamento do implante (supra ou infraósseo), não foram relatadas diferenças quanto à formação da papila. Por fim, a altura determinante para a formação da papila do ponto de contato da coroa à crista óssea deve ser de até 5mm.

The interproximal papilla, among other requirements, is considered essential for success in aesthetic prostheses on implants. This article is based on a review of literature in journals from 1984 to 2011 in Lilacs and Medline. 21 articles were selected in order to highlight the factors determining the formation and / or maintenance of peri-implant papilla, such as distance between tooth and implant, implants between his position and the bone above or below the required distance from the contact point to the crest marrow. Concluded that the distance between tooth implant is 2 mm, between the implant and the implant is 3 mm, whereas the height of the gingival papilla formation is sustained by biological space. Regarding the positioning of the implant, bone supra or infra, no differences were reported as the papilla formation. And the height of the papilla determining the formation of the contact point to the bone crest crown should be up to 5 mm.

Deflexão mandibular medial relacionada às falhas biomecânicas da prótese fixa implantossuportada com conexão rígida distal ao forame mentual / Medial mandibular flexure related to biomechanical failures of implant-supported fixed prosthesis with distal rigid connection to the mental foramen

Introdução: algumas falhas mecânicas e possíveis problemas biológicos foram relacionados à deflexão mandibular medial em indivíduos que possuíam próteses fixas implantossuportadas extensas, com conexão rígida bilateral em implantes posteriores ao forame mentual. Métodos: a pesquisa literária pertinente ao tema foi realizada a partir da consulta à base de dados MEDLINE, compreendendo os anos de 1954 até 2010. A proposta dessa revisão de literatura foi relacionar as possíveis falhas biomecânicas das próteses implantossuportadas com extensão distal ao forame mentual, tais como fratura de implantes, afrouxamento ou fratura de parafuso da prótese, falta de assentamento passivo da estrutura metálica, saucerização e, em alguns casos, dor muscular e limitação de abertura de boca, e propor o desenho dessas próteses. Conclusão: quando o planejamento protético necessitar elementos de apoio na parte posterior ao forame mentual, a prótese deverá ser segmentada, principalmente em região de sínfise. Dessa forma, os efeitos deletérios causados pela deflexão mandibular medial na prótese e região peri-implantar serão minimizados.

Reabilitação de maxila atrófica com prótese implantossuportada empregando quatro fixações zigomáticas: relato de caso clínico / Rehabilitation of atrophic maxilla with implant-supported prosthesis using four zygomatic fixation: case report

A reabilitação de pacientes com maxila severamente atrófica é um dos maiores desafios na Implantodontia atual. A grande dificuldade inerente da reabilitação e a necessidade de extensas reconstruções ósseas (enxertos onlay, levantamento de seio maxilar) podem elevar o grau de morbidade cirúrgica e o tempo de tratamento. As fixações zigomáticas têm sido apresentadas na literatura como uma opção viável para o tratamento de pacientes com esse quadro clínico. Neste artigo será apresentado o relato de um caso clínico com reabilitação da maxila por meio da instalação de quatro implantes zigomáticos e uma prótese fixa parafusada sobre os implantes, instalada dois dias após a cirurgia, submetendo os implantes à carga imediata.

The rehabilitation of patients with severely atrophic maxilla is one of the greatest challenges in implant dentistry today. The difficulty inherent in this rehabilitation and the need for extensive bone reconstruction (onlay grafts, sinus Iifting) can raise the level of surgical morbidity and treatment time. The zygomatic fixations have been presented in literature as a viable option for the treatment of patients with this clinical scenario. This paper reports a clinical case of rehabilitation of the maxilla through the installation of four zygomatic implants and a fixed prosthesis screwed over the implants, installed two days after surgery, with the implants subjected to immediate loading.

Deflexão mandibular medial relacionada às falhas biomecânicas da prótese fixa implantossuportada / Midline mandibular deflection and possible biomechanical failures on implant-supported dental prostheses - literature review

Algumas falhas mecânicas e possíveis problemas biológicos foram relacionados à deflexão mandibular medial em indivíduos que possuíam próteses fixas implantossuportadas extensas, com conexão rígida bilateral em implantes posteriores ao forâmen mentual. A pesquisa literária pertinente ao tema foi realizada a partir da consulta à base de dados Medline, compreendendo de 1954 até 2010. A proposta desta revisão da literatura foi relacionar as possíveis falhas biomecânicas das próteses implantossuportadas com extensão distal ao forâmen mentual, tais como fratura de implantes, afrouxamento ou fratura de parafuso da prótese, falta de assentamento passivo da estrutura metálica, saucerização e, em alguns casos, dor muscular e limitação de abertura da boca e propor o desenho dessas próteses. Como conclusão, baseando-se na revisão da literatura selecionada, quando o planejamento protético necessitar de elementos de apoio na parte posterior ao forâmen mentual, a prótese deverá ser segmentada, principalmente em região de sínfise. Desta forma, os efeitos deletérios causados pela deflexão mandibular medial na prótese e região peri-implantar serão minimizados.

Some mechanical failures and possible biological problems were related to the mandibular midline deflection in individuals who had extensive fixed implant-supported dental prosthesis with bilateral rigid connection posterior to the mental foramina. A literature review relevant to the topic was performed in the Medline comprising the years from 1954 until 2010. The purpose was to relate the possible biomechanical failures of implant-supported dental prosthesis extending distal to the mental foramen such as implant fracture, prosthesis screw loosening or fracture, lack of passive fit of the metallic structure, bone saucerization, and in some cases, reports of muscle pain and limited mouth opening, to determine prosthesis design. In conclusion, when prosthetic reconstructions demand supporting elements distal to the mental foramen, the prosthesis should be segmented, especially in the symphyseal area. Thus, they neutralize the deleterious effects of midline mandibular flexion in the prosthesis and peri-implant regions.

Utilização de osso humano fresco congelado para aumento vertical na região posterior de mandíbula / Vertical augmentation at the posterior mandibular area with fresh-frozen human bone

A resolução do edentulismo posterior em mandíbula atrófica vem sendo um dos grandes desafios para o implantodontista. Neste sentido, a busca por diferentes biomateriais, entre eles o osso homógeno, tem sido estudada como potenciais substitutos ósseos em cirurgias reconstrutivas. O objetivo deste estudo foi demonstrar a possibilidade da utilização de osso humano fresco congelado, proveniente de tecido ósseo cortical de fêmur, em um procedimento de aumento vertical na região posterior de mandíbula e, através da análise estatística, avaliar o grau de ganho em altura óssea, o grau de reabsorção óssea e as complicações decorrentes da técnica empregada. Foram realizados 12 procedimentos de enxerto na área posterior da mandíbula. Os resultados do estudo foram avaliados clinicamente através de mensurações que foram comparadas com tomografias antes e após seis meses. Concluímos que a utilização do osso humano fresco congelado promoveu a formação óssea em altura de 4,75 ± 0,26 mm. A reabsorção dos enxertos foi considerada estatisticamente nula e, quanto ao quesito das complicações decorrentes da técnica empregada, existiu diferença estatisticamente significante entre os percentuais de fratura do bloco, mobilidade clínica e parestesia. Dos 12 enxertos colocados, quatro apresentaram deiscência de sutura, resultando em 66,7% de sucesso. Neste sentido, a reconstrução em altura da região posterior de mandíbula, com osso homógeno cortical, torna-se viável seguindo corretamente os passos e cuidados da técnica empregada.

Edentulous posterior mandibular atrophic areas have become a challenge for surgeons. For this, different biomaterials have being studied, being the fresh-frozen allograft bone applied in several works. The aim of this study was to demonstrate that the human fresh bone, proceeding from the cortical femoral area, can be used to reconstruct the lower jaw area. The new bone height level, bone resorption and the complications was analyzed statistically. Twelve lower jaw posterior bone graft procedures were performed, and the results evaluated clinically and measured with CT scans before and six months after surgery. We concluded that the allograft bone promoted a height bone formation of 4.75 ± 0.26 mm. Bone resorption was considered statistically non-significant. Statistically significant differences were seen for factors such as bone harvest fracture, clinical mobility, and paresthesia. Suture dehiscence was observed in 4 of 12 of these blocks, resulting in success rate of 66.7%. Vertical augmentation at posterior atrophic mandibular areas can be done with fresh-frozen bone using adequate surgical procedures.

Análise in vivo do silicone vedando à infiltração de bactérias na interface pilar/implante / In vivo effectiveness of silicone gel sheets as a barrier at the inner microgap between

Neste estudo foi avaliada a eficácia da colocação de uma placa de silicone para tentar vedar a interface entre o pilar protético e a base de 22 implantes de hexágono externo osseointegrados, em 14 pacientes com boa condição clínica dos tecidos peri-implantares e portadores de coroas protéticas, em intervalo de tempo que variava de dois a 36 meses. As amostras foram coletadas desses microespaços antes, 30 e 90 dias após da inserção da membrana de silicone. Os DNA bacterianos foram extraídos e submetidos, em triplicata, à reação em cadeia da polimerase (PCR) com o uso de iniciadores específicos para os patógenos peri-implantares Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia e Tannerella forsythensis. Nas amostras iniciais foi constatada uma positividade de 48%, valor estatisticamente diferente do encontrado nas amostras coletadas após 30 (33%; p = 0,0652) e 90 dias (27%; p = 0,0081); aos 90 dias apresentou-se p < 0,05 indicando diferença significativa após a inserção da membrana. Assim, ficou evidenciado que a placa de silicone apenas reduziu, mas não impediu a penetração de nenhuma destas espécies no interior dos implantes de hexágono externo.

In this study the efficiency of the placing of a silicone membrane in order to seal the interface between the prosthetic abutment and the foundation of 22 external hexagonal connection implants was evaluated in 14 patients with good clinical conditions of the peri-implant tissues and implant-suppored prostheses varying from 2 to 36 months. The samples were collected in these microgaps before the insertion of the silicone membrane, 30, and 90 days later. The bacterial DNA were extracted and triplicated following polymerase chain reactio (PCR) with the use of specific initiators for the pathogenic peri-implant Aggregatibacter actinomycetemcomitans, Porphyr omonas gingivalis, Prevotella intermedia and Tannerella forsythensis species. In the initial samples, 48% of positive results were presented, a number statistically different from those found in samples collected after 30 (33%; p = 0,0652) and 90 days (27%; p = 0,0081); at 90 days, p values of < 0,05 were found, showing a significant difference after the membrane insertion. It was concluded that the silicone membrane just reduced but did not prevent infiltration of all tested species inside the external hexagon connections.

Análise fotoelástica das tensões induzidas em implantes por próteses parciais fixas cimentadas, parafusadas e mistas / Photoelastic analysis of implant-supported, screwed, cemented, and screwed/cemented frameworks

O uso de próteses implantossuportadas tornou-se uma modalidade terapêutica altamente difundida e confiável para a reabilitação de pacientes edêntulos. O sucesso dessa terapia está associado a um equilíbrio entre fatores biológicos e mecânicos. Em próteses sobreimplantes, a retenção se faz por meio de parafusos ou cimentos; entretanto, não existe um consenso na literatura sobre a melhor opção. Assim, testes de tensão programados foram utilizados para determinar a transferência de tensão de 20 infraestruturas, sendo cinco parafusadas, cinco cimentadas e dez mistas (alternando-se a sequência de pilares) aos implantes, com o objetivo dos resultados obtidos serem de interesse clínico. Através deste estudo observou-se a formação de franjas isocromáticas, resultado das tensões geradas ao redor dos implantes após a instalação das diferentes infraestruturas e, após a aplicação da carga axial compressiva de 100 N, podemos concluir a falta de adaptação passiva desta infraestrutura pela formação de tensões de baixa magnitude em alguns implantes. As infraestruturas cimentadas e mistas revelaram níveis mais baixos de distribuição de tensão quando submetidas à carga compressiva, comparadas às próteses parafusadas.

Nova técnica de aumento vertical de mandíbula posterior com osso alógeno fresco congelado particulado / Vertical gain in posterior lower jaw using fresh crushed allograft bone

Com o advento da Implantodontia moderna, tem sido cada vez maior a utilização de enxertos buscando a reconstrução da reabsorção óssea advinda da perda do elemento dental. O objetivo deste estudo clínico é apresentar uma nova técnica de incorporação de enxerto de osso alógeno fresco congelado particulado em procedimentos de aumento vertical de rebordo posterior de mandíbula atrófica, através de uma cúpula rígida metálica que confere proteção e estabilidade ao material de enxerto.