An overview of implant overdenture attachment systems

Implant-retained overdentures have revolutionized dental prosthetics, addressing the limitations of traditional removable dentures. These overdentures rely on attachment systems to anchor them to dental implants or abutments, improving stability, retention, and functionality. Common attachment systems include locator attachments, bar attachments, magnets, Hader clips, ERA attachments, telescopic crowns, and OT equator attachments. Each offers unique benefits and retention levels. Implant survival rates are influenced by various factors, including attachment type, but overall, attachment choice may not be the primary determinant of implant success. Attachment systems that evenly distribute forces, like bar attachments, contribute to implant stability. Marginal bone loss can affect implant stability and is influenced by attachment systems. Precision attachments, such as telescopic crowns, have shown reduced marginal bone loss in practice. Soft tissue complications, including inflammation and mucositis, vary by attachment but can be managed with proper oral hygiene. Retention, crucial for function, varies with attachment type and implant number. More implants generally improve retention, although it may decrease over time. Bar attachments typically provide superior retention. Maintenance is essential, with some debate over whether bar or stud designs entail more upkeep. Patient satisfaction is high with both bar and ball attachments, while magnets may pose retention issues. The choice of attachment depends on patient needs and clinical factors, with regular follow-up and maintenance essential for long-term success.

Carga inmediata de implantes extra cortos en sectores posteriores. Estudios retrospective con tres modelos de carga: 24, 48 hs y 7 días / Immediate loading of extra short implants in posterior sectors. Retrospective study with three loading models: 24 hs, 48 hs and 7 days

Los implantes extra-cortos son cada vez más utili-zados en la práctica clínica diaria. La utilización de estos implantes con carga inmediata supone un reto añadido. Clásicamente se ha postulado que la carga inmediata debe realizarse después de 24 horas de la cirugía. En la siguiente serie de casos analizamos diferentes tiempos a la hora de realizar la carga in-mediata y su posible repercusión. Fueron recolec-tados de forma retrospectiva datos sobre casos de implantes extra-cortos (5,5 y 6,5 mm) en los que fue realizada una carga inmediata en sectores poste-riores. El implante fue la unidad de análisis para la estadística descriptiva en cuanto a la localización, dimensiones del implante, y mediciones radiográ-ficas. El paciente fue la unidad de medida para el análisis de la edad, sexo y la historia clínica. La prin-cipal variable estudiada fue la supervivencia de los implantes extra-cortos con carga inmediata en tres períodos de tiempo determinados: 24 hs, 48 hs y 7 días y como variables secundarias se han estudiado, la estabilidad del hueso crestal en general y en los tres períodos de carga anteriormente mencionados, las complicaciones protésicas y la supervivencia de las prótesis. Fueron reclutados 74 pacientes en los que se insertaron 146 implantes que cumplieron con los criterios de inclusión. Todos los implantes fueron cargados mediante carga inmediata en tres perío-dos determinados de tiempo: 24 hs (40 implantes), 48 hs (42 implantes) y 7 días (42 implantes). Todos los implantes fueron ferulizados a otros implantes ge-nerándose puentes de dos o más unidades, con di-ferente longitud. En el grupo de implantes con carga inmediata en 24 hs la media de la pérdida ósea distal de todos los implantes fue de 0,21 mm (+/-0,84) y la media de la pérdida ósea mesial en este grupo fue de 0,33 mm (+/- 0,53). En el grupo de carga inmediata en 48 hs, la media de la pérdida ósea distal de todos los implantes fue de 0,20 mm (+/- 0,82) y la media de la pérdida ósea mesial fue de 0,22 mm (+/- 0,81). En el grupo de carga de 7 días, la pérdida ósea me-sial del grupo fue de 0,28 mm (+/- 0,51) y la media de la pérdida ósea distal fue de 0,17 mm (+/- 0,81). Cuando comparamos las medias de pérdida ósea me-sial y distal entre los tres grupos, no se observaron diferencias estadísticamente significativas (mesial p=0,062, distal p=0,067). En conclusión, no se obser-varon diferencias significativas en la pérdida ósea crestal ni en la supervivencia de los implantes cortos entre los 3 tiempos estudiados de aplicación de car-ga inmediata. Por ello, utilizar cualquiera de los tres protocolos puede ser adecuado, mientras se realice un correcto análisis de la situación clínica de cada paciente (AU)

Extra-short implants are increasingly used in daily clinical practice. The use of these implants with immediate loading poses an added challenge. Classically it has been postulated that immediate loading should be performed 24 hrs after surgery. In the following case series, we analyze different times of immediate loading and their possible repercussions. We retrospectively collected data on cases of extra-short implants (5.5 and 6.5 mm) in which immediate loading was performed in posterior sectors. The implant was the unit of analysis for descriptive statistics in terms of location, implant dimensions, and radiographic measurements. The patient was the unit of measurement for the analysis of age, sex and medical history. The main variable studied was the survival of immediately loaded extra-short implants in three specific time periods: 24 hrs, 48 hrs and 7 days. Secondary variables studied were crestal bone stability in general and in the three loading periods mentioned above, prosthetic complications and prosthesis survival. Seventy-four patients were recruited and 146 implants that met the inclusion criteria were inserted. All implants were loaded by immediate loading in three specific time periods: 24 hrs (40 implants), 48 hrs (42 implants) and 7 days (42 implants). All implants were splinted to other implants generating bridges of two or more units, with different lengths. In the 24-hr immediate loading group the mean distal bone loss of all implants was 0.21 mm (+/- 0.84) and the mean mesial bone loss in this group was 0.33 mm (+/- 0.53). In the 48-hr immediate loading group, the mean distal bone loss for all implants was 0.20 mm (+/- 0.82) and the mean mesial bone loss was 0,22 mm (+/- 0,81). In the 7-day loading group, the mesial bone loss of the group was 0.28 mm (+/- 0.51) and the mean distal bone loss was 0.17 mm (+/- 0.81). When we compared the mean mesial and distal bone loss between the three groups there were no statistically significant differences (mesial p=0.062, distal p=0.067). In conclusion, no significant differences were observed in crestal bone loss or in the survival of short implants between the 3 immediate load application times studied. Therefore, using any of the three protocols can be appropriate, as long as a correct analysis of the clinical situation of each patient is performed (AU)

Survival of dental implants in oncology patients versus non-oncology patients: a 5-year retrospective study

Abstract Patients with a history of cancer are increasingly common in the dental office. Treating cancer patients requires a multidisciplinary team, which should include the dentist, in order to control the complications that occur in the oral cavity and also to recover the patient undergoing treatment in any of its types: surgical, medical, radiotherapeutic, or its possible combinations. Dental implants can be a safe and predictable treatment option for prosthetic rehabilitation. The aim of this paper is to describe in retrospect the success rate of osseointegrated implants in oncology and non-oncology patients placed by the Master of Dentistry in Oncology and Immunocompromised Patients, as well as the Master of Medicine, Surgery and Oral Implantology of the University of Barcelona Dental Hospital, between July 2011 and March 2016. 466 patients were reviewed, with a total of 1405 implants placed, considering the oncological history of the patients and the implant success rate. The total success rate in the concerned period was 96.65%. When comparing cancer patients with healthy ones, the success rate has been 93.02% in the first case, and 97.16% in the latter. According to the literature review, our results encourage implant placement in cancer patients, it is important to recognize that this is an analysis of a complex care pathway with a large number of confounding variables. However, the findings should not be considered as generalizable.

Resumo Pacientes com histórico de câncer são cada vez mais comuns no consultório odontológico. O tratamento de pacientes com câncer requer uma equipe multidisciplinar, que deve incluir o dentista, a fim de controlar as complicações que ocorrem na cavidade oral e também para tratar o paciente com qualquer uma das modalidades de tratamento: cirúrgica, médica, radioterápica ou suas possíveis combinações. Os implantes dentários podem ser uma opção de tratamento segura e previsível para reabilitação protética. O objetivo deste artigo é propor um estudo retrospectivo sobre a taxa de sucesso de implantes osseointegrados em pacientes oncológicos e não oncológicos atendidos no Mestrado em Odontologia em Pacientes Oncológicos e Imunodeprimidos, bem como no Mestrado em Medicina, Cirurgia e Implantodontia Oral do Hospital Odontológico da Universidade de Barcelona, entre julho de 2011 e março de 2016. Foram revisados 466 pacientes, com um total de 1405 implantes instalados, considerando o histórico oncológico dos pacientes e a taxa de sucesso do implante. Resultados: A taxa de sucesso total no período em questão foi de 96,65%. Na comparação entre pacientes com câncer e saudáveis, a taxa de sucesso foi de 93,02% no primeiro caso e 97,16% no segundo. Conclusão: De acordo com a revisão da literatura, nossos resultados encorajam a colocação de implantes em pacientes com câncer, é importante reconhecer que esta é uma análise complexa que requer cuidado devido ao grande número de variáveis. No entanto, os resultados não devem ser considerados de forma generalizada.

Clinical observation of cement-retained and screw-retained implant-supported denture in edentulous patients / 口腔疾病防治

Objective@# To evaluate the clinical effects of full-arch cement-retained implant-supported combined crowns and screw-retained implant-supported bridge dentures in complete or half edentulous patients. @*Methods @#A total of 25 patients with complete or partial edentulous dentures followed up for 1, 3, and 5 years in our hospital from June 2013 to June 2018 and were treated with Straumann bone horizontal implantation, cobalt-chromium stenting and cobalt-chromium porcelain restoration with cement-retained and screw-retained implant-supported fixed dental prostheses to evaluate the accumulative implant survival rate, accumulative prosthesis survival rate, mechanical complications, and biological complications in both groups. @*Results @#There were 25 complete or half edentulous patients who received 165 Straumann implants and 28 implant-supported fixed dental prostheses in this study. There were 11 cases with 69 implants in the cement group and 17 cases with 96 implants in the screw group. The accumulative implant survival rate was 100% in the cement group and 96.9% in the screw group. The accumulative prosthesis survival rate was 100% in both groups. The cumulative peri-implant mucositis rate was 23.2% in the cement group and 29.2% in the screw group, and the peri-implantitis rate was 6.8% in the cement group and 7.3% in the screw group. There was 1 case of porcelain collapse (n=1/11) and no screw of abutment loosening in the cement group and 4 cases of porcelain collapse (n=4/17) and 1 case of screw loosening in the screw group. No fracture of abutment was observed in either group. There was no difference in bone loss between the two groups in the first year (P > 0.05), and a higher rate of bone loss was found in the screw group in the third and fifth years (P < 0.05). There was no difference in the sulcus bleeding index(mSBI) between the two groups in the first year and the third year (P > 0.05) and a higher modified mSBI value in the cement group in the fifth year (P < 0.05).@*Conclusion @#The survival rates of the implant and prosthesis for cement-retained or screw-retained implant-supported fixed dental prostheses were both high, but there were more mechanical and biological complications in the traditional cobalt-chromium alloy screw-retainer group. The removal of residual adhesives must be reasonably considered when choosing the cement retention method.

Research progress on the crown-implant ratio and clinical complications / 口腔疾病防治

@#The crown-root ratio (C/R) theory of natural teeth has been widely recognized in the field of stomatology,and has important clinical significance in predicting and assessing the prognosis of natural teeth as well as for abutment selection during denture restoration. In the past few decades, scholars have advocated for the implantation of implants as long in length as possible to improve the success rate according to the theory of crown-root ratio of natural teeth. However, with the application of short implants, our philosophy of implantation has changed, and the relationship between the crown-implant (C/I) ratio and complications has become one of the current research hotspots. In this paper, the concept of the crown-implant ratio, the research progress of the C/I ratio, the implant survival rate and clinical complications of implant restoration were reviewed and summarized, and the following suggestions were put forward: although most studies have shown no significant correlation between the C/I ratio and implant survival or marginal bone loss, this relationship may increase the risk of mechanical complications. A C/I < 3 and a crown length < 15 mm are recommended in implant restoration; when ultra-short implants are applied, the implant system can increase the bone-to-implant contact area, and splint prostheses such as crown or bridge are recommended.

“Burden of the Triumph:” Burden of peri-implantitis in Indian population – A mathematical model

India suffers from a heavy burden of oral diseases. Dental implants (DIs) are prescribed widely by the dental practitioners to replace lost natural teeth. There is no estimate, however, to determine the number of DIs or the number of people with peri-implantitis or the failure of implants after placement. In this modeling study, we attempted to estimate the prevalence of adult Indians who would choose DI in the near future and to calculate the peri-implantitis and failure of DI. Materials and Methods: Using the Global Burden of Disease database (2016), the number of dental caries in permanent dentition, periodontal diseases, and edentulism was obtained. Empirical assumptions of patients with anodontia in urban and rural areas who opted for DI, percentage of implants placed, the affordability factors, and mathematical models for DI were formed and executed. Peri-implantitis and survival data from literary evidence were collated. Results: Based on assumptions, 909,643 Indians, (830,231–858,703) would choose DI. Estimated number of peri-implantitis would be 145,543–254,700 and estimated number of failures should be 50,940–79,412 in the near future. Conclusions: In spite of the high economic challenge and the risks or complications of peri-implantitis, DIs are gaining prominence. It is the dentists' burden to face the renewed challenges due to emerge and provide remedial measures.

Acetabular Subchondral Bone Decortication and Its Role in the Outcome of Cemented Total Hip Replacement in Young Patients / 대한고관절학회지

PURPOSE: Long-term fixation of cemented acetabular components can be problematic in younger active patients. Our technique is put forward to improve outcomes and maximize implant survivorship in this particular patient population. MATERIALS AND METHODS: We report on a cohort of young adult patients (less than 55 years old) with cemented total hip replacement (THR) using a novel technique in preparing and cementing the acetabulum with a minimum follow-up of 10 years (mean follow-up, 14 years). Retrospectively collected data on clinical and radiological outcomes were reviewed. RESULTS: Sixty-five THRs were performed with the minimum study follow-up period. Average age for patients was 44 years old (range, 19–55 years). The mean Hip Disability and Osteoarthritis Outcome Score for patients at final appointment was 92.7. Radiographs taken at an average of 14 years after operation showed 63 of 65 hips showed no evidence of any radiological loosening. Cup survivorship was 100% at the end of the study period. CONCLUSION: Our technique of preparing the acetabulum in combination with cement fixation is reproducible with excellent results in a cohort of patients prone to early aseptic loosening of the acetabular component.

Parameters Associated with Marginal Bone Loss around Implant after Prosthetic Loading

Abstract This study evaluated retrospectively the association among occlusal, periodontal and implant-prosthetic parameters and marginal bone loss (MBL) around implants and survival rate at 5.7 ±3.2 years of follow-up after prosthetic loading. Eighty-two patients received 164 external hexagon implants. After the standard healing period (3 to 6 months), the implants were restored with single-tooth or up to three splinted crowns. All patients were followed according to a strict maintenance program with regular recalls and clinically evaluated by a calibrated examiner. The MBL measurements taken from standardized radiographs made at permanent crown placement (baseline) and after the last evaluation were calculated considering occlusal, periodontal and implant-prosthetic parameters. Veneer fractures and abutment loosening were not considered failure. Two implants failed during the follow-up period, resulting in a survival rate of 98.8%. Cox regression analyses showed MBL associated with non-working side contacts (p=0.047), inadequate anterior guidance (p=0.001), lateral group guidance involving teeth and implants (p=0.015), periimplant plaque index (p=0.035), prosthetic design (p=0.030) and retention (p=0.006). Inadequate occlusal pattern guide, presence of visible plaque, and cemented and splinted implant-supported restoration were associated with greater MBL around the implant.

Resumo Este estudo avaliou retrospectivamente a associação entre os parâmetros oclusais, periodontais e implante-protéticos e perda óssea marginal (POM) ao redor de implantes e taxa de sobrevivência, em 5,7 ± 3,2 anos de acompanhamento após o carregamento protético. Oitenta e dois pacientes receberam um total de 164 implantes com hexágono externo. Após o período de cicatrização (3 à 6 meses), os implantes foram restaurados com coroa unitária ou até três coroas ferulizadas. Todos os pacientes seguiram um programa de manutenção rigoroso, com consultas regulares e avaliações clinicas realizadas por um examinador calibrado. As medições de POM obtidas de radiografias padronizadas realizadas na colocação da coroa permanente (baseline) e após a última avaliação foram calculadas considerando os parâmetros oclusais, periodontais e àqueles relacionados ao implante e prótese. Fratura na cerâmica de cobertura e afrouxamento do pilar não foram considerados falhas. Dois implantes falharam durante o período de acompanhamento, resultando em uma taxa de sobrevivência de 98,8%.A análise de regressão de Cox mostrou POM associado com contatos no lado de balanceio (p= 0,047), inadequada guia anterior (p=0,001), guia lateral em grupo envolvendo dentes e implantes (p=0,015), índice de placa visível em torno do implante (p=0,035), tipo de prótese (p= 0,030) e retenção (p=0,006). Guia de padrão oclusal inadequado, presença de placa visível e restaurações implanto-suportadas cimentadas e ferulizadas resultaram em maior POM ao redor do implante.

Avaliação das taxas de sucesso e sobrevivência de 497 implantes há cinco anos ou mais em função – estudo retrospectivo com 139 pacientes / Success and survival rates of 497 implants with at least 5 years of function – a retrospective study with 139 patients

Objetivo: avaliar as taxas de sucesso e sobrevivência de implantes há cinco anos ou mais em função. Material e métodos: pacientes tratados com implantes de titânio (Implacil De Bortoli, São Paulo, Brasil) na Fundecto (USP), no período de 1998 a 2008 foram incluídos neste estudo. Os implantes foram classificados individualmente, de acordo com um rigoroso critério de sucesso. Também foram levados em consideração o formato e o tipo de plataforma dos implantes. Resultados: a taxa de sobrevivência dos implantes tipo hexágono externo (n=357) e interno (n=140) foi de 99,4% e 99,3%, respectivamente. Já com relação aos implantes cônicos (n=88) e cilíndricos (n=409), a taxa de sobrevivência foi de 100% e 99,3%, respectivamente. A taxa de sucesso para implantes tipo hexágono externo e interno foi de 90,8% e 93,6%, respectivamente. Implantes cônicos obtiveram 90,9%, enquanto que implantes cilíndricos apresentaram 91,7% de taxa de sucesso. Conclusão: de acordo com o presente estudo, a taxa geral de sobrevivência dos implantes foi de 99,4%, enquanto a taxa de sucesso foi de 91,5%.

Objective: to assess success and survival rates from implants in function for five or more years. Material and methods: patients treated with osseointegrated implants (Implacil De Bortoli, Sao Paulo, Brazil) at Fundecto (USP), from 1998 to 2008, were included in this study. Implants were individually classified using strict success criteria. For further analysis, data were obtained regarding implant’s platform and implant’s macro design. Results: survival rates for external (n=357) and internal hexagon implants (n=140) were 99,4% and 99,3%, respectively. Regarding tapered (n=88) and cylindrical implants (n=409), survival rates were 100% and 99,3%, respectively. Success rates for external and internal hexagon implants were 90,8% and 93,6%. Tapered implants had 90,9% and cylindrical implants presented 91,7% of success rates. Conclusion: according to this retrospective study, the overall survival rate was 99,4% and the overall success rate was 91,5%.

Estudos longitudinais e sucesso na implantodontia / Longitudinal studies and success rates in implant dentistry: a literature review

Atualmente, observamos maior procura pelos tratamentos através dos implantes osseointegráveis para a reabilitação dos dentes perdidos. Isto deve-se a uma crescente conscientização dos pacientes em relação ao sucesso e aos benefícios dos implantes. Com isso, torna-se fundamental a busca por técnicas, materiais e protocolos que forneçam maior segurança e previsibilidade aos tratamentos, bem como a necessidade da realização de mais estudos longitudinais. O primeiro estudo avaliando os implantes osseointegráveis foi publicado em 1981 e, desde então, inúmeros outros trabalhos foram realizados. Contudo, estudos longitudinais que realizaram um acompanhamento a longo prazo ainda são escassos. Desta forma, o objetivo do presente trabalho foi realizar, através de uma revisão da literatura, a busca de estudos longitudinais avaliando o desempenho clínico dos implantes, bem como os parâmetros e as escalas de sucesso utilizados por eles.

Nowadays, there is an increasing demand for dental implant treatment to replace lost teeth. This can be due to great patient awareness about the related success and benefits of this therapy. Thus, the use of well-established materials, techniques, and protocols for predictable outcomes, as well as new longitudinal studies, is mandatory. The first study on osseointegrated implants was published in 1981 and since then several papers were presented. However, long-term studies are scarce. In this way, the aim of this paper is to review longitudinal studies regarding the long-term performance of dental implants along with its scales and parameters used to define success levels.

Influencia del diámetro y longitud de implantes en la pérdida tardía de implantes dentales / Influence of diameter and length of implant on late dental implant failure

El objetivo de esta investigación fue describir la influencia del diámetro y largo de los implantes en la pérdida tardía del implante. Se diseñó un estudio retrospectivo para estudiar 375 pacientes que habían sido sometidos a rehabilitación oral sobre implantes durante un periodo de 11 años; se incluyeron en el estudio todos aquellos documentos debidamente completados y con estudios radiográficos preoperatorios, posterior a la instalación del implante y posterior a la instalación de la prótesis. Los implantes fueron clasificados de acuerdo al diámetro como estrecho, regular y ancho y de acuerdo al largo como corto, medio y largo; el análisis de datos fue realizado con la prueba Chi Cuadrado con valor de p<0,05. Del total de 939 implantes y se identificó la pérdida de 55 implantes posterior a la etapa protésica (5,8 por ciento). En base a la pérdida, no se logró establecer ninguna relación estadísticamente significativa con el diámetro del dispositivo (p=0,475) y tampoco con el largo del implante (p=0,064). Podemos concluir que el largo y el diámetro de implantes dentales no influyen en la pérdida tardía del mismo.

The aim of this research was to describe the influence of diameter and length of dental implant related to late implant faliure. In a retrospective study was evaluated 375 patients in a 11 year period; were inclued the complet medical record with image study in the preoperative period, posteriorly to implant installation and to prosthesis installation. The implant was classified according to diameter in narrow, regular and wide, and according to length as short, regular and long. The statistical analysis was realized with Chi-Squaare test with p value <0.05. We studied 939 implants and observed 55 implant failure posteriorly to prosthesis phases (5.8 percent). No statistical relation with diameter (p=0.475) or lenght (p=0.064) was observed. We conclude that the length and diameter of dental implant is not an influence for late failure of the implant.

Evaluación clínico-radiográfica del éxito y supervivencia de implantes dentales con tratamiento de superficie e implantes con superficie torneada / Clinical-radiographic success and survival with implants dental surface treatment and surface turned

El objetivo principal del estudio fue evaluar la influencia del tratamiento de superficie del implante en el éxito y supervivencia de estos. Se evaluaron 24 pacientes que presentaban un total de 74 implantes dentales oseointegrados, 19 con superficie torneada y 55 superficie RBM® (Lifecore® Biomedical, Chaska, Minn). Los resultados obtenidos fueron una tasa de supervivencia de 98.18% para los implantes de superficie RBM®, 100% para los de superficie lisa y para el total de implantes 98.65%. La tasa de éxito para los implantes de superficie lisa fue 63.16%, para los de superficie RBM® 70.91% y para el total de implantes 68.92%; sin encontrar diferencias estadísticamente significativas entre estas. La pérdida ósea fue 1.82mm para los implantes de superficie torneada y 1.34mm para los de superficie RBM®, encontrándose esta diferencia estadísticamente significativa. Los resultados obtenidos indican que los implantes con superficie RBM® a comparación de los implantes con superficie torneada, presentan ventajas con respecto a la pérdida ósea marginal. También se observó que la variable que mayor influencia ejerce sobre la pérdida ósea marginal y el éxito del implante es el momento de la carga.

The principal aim of our study was to evaluate the survival and success rate of implants with treated surface (RBM®) and machined surface implants. 24 patients treated with 74 dental implants were evaluated. 19 machined surface implants and 55 RBM® surface implants (Lifecore® Biomedical, Chaska, Minn). The results were a survival rate of 98.18 % for RBM® implants, 100% for machined or smooth surface and 98.65 % and for the whole of implants. The success rate for smooth implants was 63.16% for RBM® implants was 70.91% and for the whole of implants was 68.92%. These results were not significantly different. However, peri-implant bone loss was significantly different between smooth implants (1.82mm) and RBM® implants 1.34. The results indicate that implants RBM present advantages with regard to the marginal bone loss. Also was observed that the load time is the variable that major influence has on the marginal bone loss and the implant success.

Survival of dental implants in native and grafted bone in irradiated head and neck cancer patients: A retrospective analysis.

Aim: To study the long-term survival of dental implants placed in native or grafted bone in irradiated bone in subjects who had received radiation for head and neck cancer. Materials and Methods: A retrospective chart review was conducted for all patients who received dental implants following radiation treatment for head and neck cancer between May 1, 1987 and July 1, 2008. Only patients irradiated with a radiation dose of 50 Gy or greater and those who received dental implants in the irradiated field after head and neck radiation were included in the study. The associations between implant survival and patient/implant characteristics were estimated by fitting univariate marginal Cox proportional hazards models. Results: A total of 48 patients who had prior head and neck radiation had 271 dental implants placed during May 1987-July 2008. There was no statistically significant difference between implant failure in native and grafted bone (P=0.76). Survival of implants in grafted bone was 82.3% and 98.1% in maxilla and mandible, respectively, after 3 years. Survival of implants in native bone in maxilla and mandible was 79.8% and 100%, respectively, after 3 years. For implants placed in the native bone, there was a higher likelihood of failure in the maxilla compared to the mandible and there was also a tendency for implants placed in the posterior region to fail compared to those placed in the anterior region. Conclusion: There was no significant difference in survival when implants were placed in native or grafted bone in irradiated head and neck cancer patients. For implants placed in native bone, survival was significantly influenced by the location of the implant (maxilla or mandible, anterior or posterior).

A retrospective study on related factors affecting the survival rate of dental implants

PURPOSE: The aim of this retrospective study is to analyze the relationship between local factors and survival rate of dental implant which had been installed and restored in Seoul Veterans Hospital dental center for past 10 years. And when the relationship is found out, it could be helpful to predict the prognosis of dental implants. MATERIALS AND METHODS: A retrospective study of patients receiving root-shaped screw-type dental implants placed from January 2000 to December 2009 was conducted. 6385 implants were placed in 3755 patients. The following data were collected from the dental records and radiographs: patient's age, gender, implant type and surface, length, diameter, location of implant placement, bone quality, prosthesis type. The correlations between these data and survival rate were analyzed. Statistical analysis was performed with the use of Kaplan-Meier analysis, Chi-square test and odds ratio. RESULTS: In all, 6385 implants were placed in 3755 patients (3120 male, 635 female; mean age 65 +/- 10.58 years). 108 implants failed and the cumulative survival rate was 96.33%. There were significant differences in age, implant type and surface, length, location and prosthesis type (P.05). CONCLUSION: Related factors such as age, implant type, length, location and prosthesis type had a significant effect on the implant survival.

Implant Survival Rates of Maxillary Sinus Augmentation: a Literature Review of Graft Materials

Dealing with dental implant failures

An implant-supported restoration offers a predictable treatment for tooth replacement. Reported success rates for dental implants are high. Nevertheless, failures that mandate immediate implant removal do occur. The consequences of implant removal jeopardize the clinician’s efforts to accomplish satisfactory function and esthetics. For the patient, this usually involves further cost and additional procedures. The aim of this paper is to describe different methods and treatment modalities to deal with dental implant failure. The main topics for discussion include identifying the failing implant, implants replacing failed implants at the exact site, and the use of other restorative options. When an implant fails, a tailor made treatment plan should be provided to each patient according to all relevant variables. Patients should be informed regarding all possible treatment modalities following implant failure and give their consent to the most appropriate treatment option for them.

Analysis on cause of failure of guided bone regeneration during implant placement: A retrospective study / 대한치주과학회지

PURPOSE: The aim of this retrospective study is to evaluate survival rate of implant and bone formation, to analyze failure contribution factor. MATERIAL AND METHODS: A total of 52 consecutive patients(35 male, 17 female, mean age 49 years) with 104 osseous defects were treated during the period from October 2004 to June 2007 with a simultaneous or staged GBR approach using non-resorbable or resorbable membranes combined with autogenous bone grafts or xenograft(Bio-Oss, Bio-cera, BBP). RESULT: A total of 32(30.8%) of 104 GBR-treated sites failed the bone formation and a total of 5(5.6%) of 89 implants were removed. Early exposure of the membrane has significantly affected bone formation(p<0.05). Non-resorbable membrane showed more exposure of the membrane and low success rate of bone formation than resorbable membrane(p<0.05). There were no difference between success rate of bone formation and using autogenous bone or graft materials. There were no statistically significant difference between success rate of bone formation and smoking or using PRP. Mandible showed more success rate of bone formation than maxilla(p<0.05). CONCLUSION: Early exposure of the membrane, membrane type and maxilla/mandible type have influence on success rate of bone formation during GBR.

A retrospective study on survival rate of the most posterior single tooth implant / 대한치주과학회지

PURPOSE: The purpose of this study was to assess the long term survival rates of the most posterior single tooth implant and to evaluate the influence of implant characteristics on implant survival. MATERIAL AND METHODS: This retrospective report presents findings on 37 patients with 43 implants replacing single molars. The inclusion criteria were having implants replacing a molar of the most posterior region and follow-up data over at least 6 months. Data were recorded regarding the incidence of complications and survival rates of these implants. RESULTS: The range of follow-up was from 9 to 66 months(mean: 40.2 months). The cumulative survival rate of total implants was 93.0% which reflects the loss of three implants: one had broken neck, one implant failed because of infection, one implant showed failed osseointegration. Abutment- screws loosening occurred in five implants(11.6%). CONCLUSION: Within the limits of this study, a single tooth-implant can serve as a good long-term and predictable treatment modality to replace the most posterior teeth with low complication and failure rates.

Survival rate of implant placement in the maxilla treated with sinus elevation by the lateral approach: A retrospective study / 대한치주과학회지

PURPOSE: Osseointegration of implants in patients with pneumatized maxillary sinuses is difficult to achieve due to the deficiency of available bone in the posterior maxilla after loss of teeth. Maxillary sinus elevation is a method to overcome this problem. In this study, we evaluated the implant survival rate and the relationship between implant survival in patients with sinus elevation by the lateral approach. MATERIALS AND METHODS: A total of 48 patients were consecutively treated with sinus elevation by the lateral approach between February 2003 & August 2006 at the dental hospital of Chonbuk National university. A total of 113 implants were placed. The mean healing period was 7.1 months and implants were placed after a mean period of 5.6 months. The mean observation period was 21.8 months. RESULTS: Out of the 113 implants placed, fifteen failed, resulting in a survival rate of 86.7%, 18 cases of sinus membrane perforation were observed out of 65 sinuses treated. 33 implants were placed in a perforated site and 10 failed, representing a 60.7% implant survival. 80 implants were placed in a nonperforated site and 5 failed, representing a 92.6% implant survival. CONCLUSIONS: Implant placement with sinus elevation is an acceptable treatment for short term Results. Sinus membrane perforation and postoperative complications, however, may have an effect on implant failure.

A 10-year retrospective clinical study of Branemark implants / 대한치과보철학회지

STATEMENT OF PROBLEMS: There are few studies which reported the survival rates of the specific dental implant systems in the Korean population with the follow-up periods longer than 5 years. PURPOSE: This retrospective clinical study was aimed to evaluate cumulative survival rate (CSR) of Branemark implants followed for 10 years and to determine risk factors for implant failure. MATERIAL AND METHODS: A total of 271 Bra.nemark implants in 83 patients were investigated with several identified risk factors. Life table analysis was undertaken to examine the CSR. Cox regression method was conducted to assess the association between potential risk factors and overall CSR. RESULTS: Thirty implants failed. The 10-year implant CSR was 82.5%. Cox regression analysis demonstrated a significant predictive association between overall CSR and implant length (P<.05). CONCLUSION: An acceptable long-term result of Branemark implant was achieved and implant length showed a significant association with the CSR.