Double Crown-Retained Removable Prostheses Supported by Implants or Teeth and Implants: A Long-Term Clinical Retrospective Evaluation.

OBJECTIVES: The objective of this retrospective clinical study was to investigate the survival rates and complications of implant (I)-retained or tooth-implant (TI)-retained prostheses and abutments (teeth, implants) over a mean observation period of 11.26 years. The study also aimed to analyze the differences and complication rates between implant-retained double crown removable dental prostheses (I-DC-RDPs) versus tooth-implant-retained double crown removable dental prostheses (TI-DC-RDPs). MATERIAL AND METHODS: We reviewed the clinical data of 110 nonsmokers (mean age = 53.9 years) who received DC-RDPs in maxillary or mandibular arches. 153 teeth and 508 implants were used to restore partially edentulous (PE; TI-DC-RDPs; n = 53) and completely edentulous (CE; TI-DC-RDPs; n = 57) arches. Two designs of the distal extension were used: cantilevers (CANs) and saddles (SADs). Restorations were examined for abutment survival, mechanical, or biological complications. RESULTS: The 10-year survival rates were 99.3% (95% CI: 95.4-99.9%) for teeth and 99.3% (95% CI: 97.5-99.7%) for implants. The cumulative rates of TI- and I-RDPs free of technical complications were 77% and 86%, respectively. The risk of complications was not significantly different between the CAN and SAD subgroups of I-RDPs (p > 0.05). However, for TI-RDPs, technical complication risk was significantly higher in SAD type compared with CAN restorations (p = 0.02). CONCLUSIONS: I- and TI-DC-RDPs seem to be recommendable for restoration of CE or PE arches. The technical and biological complication rates were lower for I-DC-RDPs in the CE arches than for TI-DC-RDPs in the PE arches. Regarding the RDP design, CAN prostheses produced significantly fewer technical complications than did SAD prostheses.

Survival and complication rates of tooth-implant versus freestanding implant supporting fixed partial prosthesis: a systematic review and meta-analysis.

PURPOSE: This systematic review was performed to compare tooth, implant and prosthesis failures and biological and technical complications in toothimplant vs freestanding implant supported fixed partial prostheses, in order to evaluate the effectiveness and predictability in combining teeth and implants in the same fixed partial prosthesis. STUDY SELECTION: A comprehensive and systematic literature research was conducted, according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement, to identify human trials, with a minimum sample size of 10 patients, comparing tooth-implant to freestanding implant supported fixed partial prostheses. Four groups of meta-analyses were performed based on the patients treated with toothimplant vs freestanding implant-supported fixed partial prostheses: abutment failures, biological and mechanical complications, prosthesis failures, and prosthetic (technical) complications. RESULTS: The search yielded 749 records, after removal of duplicates. Based on the title assessment, the abstracts reading and the full-texts evaluation, 8 articles, published between 1999 and 2013, fulfilled the inclusion criteria and were included in the meta-analysis. The studies included were: 4 controlled clinical trials, 2 prospective and 2 retrospective cohort studies. The meta-analysis revealed no significant difference between tooth-implant and implant-implant supported fixed in the number of abutment (implant or tooth) failures, biological complications, prosthesis lost, and prosthetic complications. CONCLUSIONS: Within the limitations of the present systematic review, although the freestanding implant supported fixed partial prosthesis remains the first choice, joining teeth and implants to support fixed prosthesis in partially edentulous patients becomes a valid alternative with an acceptable success rate.

The biological width around implant.

PURPOSE: The concept of biological width has been proposed and widely used in oral implantation. This review aimed to summarize the biological width around implant in detail. STUDY SELECTION: An electronic search of the literature prior to March 2019 was performed to identify all articles related to biological width in periimplant soft tissue. The search was conducted in the MEDLINE (National Library of Medicine) database accessed through PubMed with no date restriction. The following main keywords were used: "implant", "biological width", "soft tissue", "junctional epithelium", "peri-implant epithelium", "connective tissue", "gingiva", "mucosa" (connecting multiple keywords with AND, OR). RESULTS: The identified researches focused on several aspects related to biological width in oral implantation, namely the concept, formation, remodeling, dimension, structure and function. CONCLUSIONS: Based on of the reviewed literature, the concept, formation, remodeling, structure, dimension, and functional significances of periimplant biological width are explored in this narrative review. The formation of biological width around implant is a complex process after several weeks of healing. The biological width around implant is a 3-4mm distance from the top of the peri-implant mucosa to the first bone-to-implant contact or the stabilized top of the adjacent bone, consisting of sulcular epithelium, junctional epithelium and fibrous connective tissue between the epithelium and the first bone-to-implant contact or the stabilized top of the adjacent bone. The biological width forms a biological barrier against the bacteria, influences the remodeling of soft and hard tissue around implant and has implications for clinical aspects of dental implantation.

Human non-decalcified histology of three dental implants 45 months under function-a case report.

BACKGROUND: Fracture of an implant is a quite rare event but represents an important opportunity to evaluate the peri-implant bone tissue response to implant overload in human beings. This study aimed to evaluate bone tissue around three fractured titanium implants retrieved from a human maxilla, by histomorphometric and birefringence analyses. CASE REPORT: For this, the implants and the surrounding bone were removed after having been united to a tooth in function for 45 months, by a 4-mm internal diameter trephine bur, following an undecalcified section was obtained. The results showed a rate of 77.3% of bone-to-implant contact (BIC) and 80.3% of bone area filling within the limits of the implant threads. Under circularly polarized light microscopy investigation, the amount of the transverse collagen fibers was of 48.11%, and the amount of the longitudinal collagen fibers was of 51.89%. CONCLUSION: Within the limitation of this study, the possible cause of the implant fracture could be the association of overload, inadequate implant diameter, and fragile internal hexagon connection.

The effect of rigid and non-rigid connections between implants and teeth on biological and technical complications: a systematic review and a meta-analysis.

OBJECTIVE: To assess survival, as well as technical and biological complication rates of partial fixed dental prostheses (FDPs) supported by implants and teeth. METHOD: An electronic Medline search was conducted to identify articles, published in dental journals from January 1980 to August 2015, reporting on partial FDPs supported by implants and teeth. The search terms were categorized into four groups comprising the PICO question. Manual searches of published full-text articles and related reviews were also performed. RESULTS: The initial database search produced 3587 relevant titles. Three hundred and eighty-six articles were retrieved for abstract review, while 39 articles were selected for full-text review. A total of 10 studies were selected for inclusion. Overall survival rate for implants ranged between 90% and 100%, after follow-up periods with a mean range of 18-120 months. The survival of the abutment teeth was 94.1-100%, while the prostheses survival was 85-100% for the same time period. The most frequent complications were "periapical lesions" (11.53%). The most frequent technical complication was "porcelain occlusal fracture" (16.6%), followed by "screw loosening" (15%). According to the meta-analysis, no intrusion was noted on the rigid connection group, while five teeth (8.19%) were intruded in the non-rigid connection group [95% CI (0.013-0.151)]. CONCLUSION: The tooth-implant FDP seems to be a possible alternative to an implant-supported FDP. There is limited evidence that rigid connection between teeth and implants presents better results when compared with the non-rigid one. The major drawback of non-rigidly connected FDPs is tooth intrusion.

Biomecânica da união dente-implante com plataforma restauradora reduzida, sistema de retenção tipo cone morse e roscas quadradas: uma análise por elementos finitos / Biomechanics of tooth-implant union with restorative platform reduced, restraint system morse cone type and square threads: a finite element analysis

Objetivou-se, a partir do Método dos Elementos Finitos, avaliar a biomecânica da união dente-implante e implante-implante, além de estabelecer uma análise qualitativa com achados fotoelásticos prévios. Foram planejados quatro modelos tridimensionais: dois Modelos Teste (dentes unidos a implantes) e dois Modelos Controle (a mesma condição, porém implanto suportada). Os implantes (ANKYLOS® - Dentsply) apresentaram conexão cônica, roscas quadradas e pilares Switching. Suas dimensões, ângulos externos e pilares protéticos foram obtidos a partir de um projetor de perfil. Já, dentes e próteses, a partir da visão direta, tiveram suas formas externas construídas em plataforma CAD (SOLIDSWORKS). O suporte alveolar foi configurado como um retângulo (68/30/15 mm). Todos os pilares foram posicionados no suporte alveolar, conforme os modelos físicos pré-existentes, gerando modelos sólidos. O ligamento periodontal consistiu de uma camada de 0,25 mm de espessura em poliéter (Impregum Soft, 3M Espe). Os modelos de dentes foram produzidos em dentina, pilares e implantes em titânio puro, próteses em liga Níquel-Cromo (Ni-Cr), e o suporte alveolar em resina fotoelástica (Araldite® - Produtos Químicos Ciba S/A do Brasil). As propriedades da resina foram obtidas por meio de ensaio de tração. Carga pontual, vertical e estática, de 150 N, foi aplicada. Os resultados destes ensaios evidenciaram menor concentração de tensão no aspecto cervical de implantes do grupo teste. Ao se confrontar tais achados com os fotoelásticos anteriormente obtidos, foi possível estabelecer uma relação direta entre as áreas mais solicitadas para os modelos de prótese fixa (PF) de três elementos. Concluiu-se que, para as condições estudadas ¿ conexão cônica, roscas quadradas e restauração com Plataforma Switching ¿, unir dentes a implantes parece ser uma terapia clínica viável, sugerindo, inclusive, ser mais favorável que a união de implantes entre si. Além disso, a partir da afinidade positiva entre os achados das duas técnicas, pôde-se considerar validados os modelos matemáticos de prótese fixa de três elementos

The goal of this study was to evaluate, from the Finite Element Method, the biomechanics of implant-tooth union and implant-implant and to establish a qualitative analysis with previous photoelastic findings. Four three-dimensional models were planned: two Test Models (teeth attached to implants) and two Control Models (the same condition, however implant supported). The implants (ANKYLOS® - Dentsply) showed conical connection, square threads and Switching pillars. Their dimensions, external angles and abutments were obtained from a profile projector. Already, teeth and dentures, from direct view, had their external forms built in CAD platform (SOLIDSWORKS). Alveolar support wasconfigured as a rectangle (68/30/15 mm). All the pillars were placed in the alveolar support, as the pre-existing physical models, generating solid models. The periodontal ligament consists of a layer of 0.25 mm thick in polyether (Impregum Soft, 3M Espe). The models of teeth trumped up of dentin, abutments and implants of pure titanium, prosthetics of Nickel-Chrome (Ni-Cr) alloy and alveolar support in photoelastic resin (Araldite® - Chemicals Ciba S/A of Brazil). The resin properties were obtained by traction tests. Punctual and vertical static load of 150 N was applied. The results of these tests showed lower concentration of tension in the cervical aspect of the test group implants. When comparing these findings with the photoelastic previously found, it was possible to establish a direct relation between the areas most requested for fixed prosthesis (FP) models of three elements. It was concluded that, for the studied conditions tapered connection, square threads and Platform Switching restoration , joining teeth implants seems to be a viable clinical therapy, suggesting, inclusive, to be more favorable than to join implants each other. Moreover, from the positive affinity between the findings of the two techniques, it was possible to consider validated the mathematical models of fixed prosthesis of three elements

Conexão dente-implante: uma alternativa viável? Relato de Caso Clínico usando prótese parcial removível apoiada sobre dentes e implantes / Connection tooth-implant: a viable alternative?Case report using removable partial denture supported on teeth and implants

As fissuras labiopalatinas levam os profissionais a idealizarem próteses não convencionais na busca da solução das reabilitações por se tornarem, muitas vezes, bastante complexas. Próteses totalmente implanto-suportadas devem ser o tratamento de escolha, embora haja casos em que a união de dentes com implantes é inevitável. Há autores que defendem a união rígida, outros a não rígida e outros ainda que não recomendem a união dente-implante. Os riscos relacionados a esta união são resultado de diferenças biomecânicas entre as estruturas envolvidas, ligamento periodontal e osso, e da biomecânica dos dentes e implantes apoiados sobre as próteses. Objetivo: este trabalho relata um caso clínico de reabilitação oral com uma PPR sobre dentes unidos a implantes em uma paciente com fissura labiopalatina do Hospital de Reabilitação de Anomalias Craniofaciais de Bauru. Método: relato do caso. Resultados e Discussão: paciente de 47 anos, gênero feminino, portadora de fissura pós-forame incisivo incompleta, apresentava os dentes 13, 23 e 27, sendo este extraído por problemas periodontais, e 2 implantes instalados nas regiões dos dentes 16 e 26. O planejamento reabilitador protético foi a instalação de uma PPR com encaixe tipo barra-clip retida por 3 barras metálicas unindo os dentes aos implantes por meio de um sistema tubo parafuso. A união não-rígida demonstra maior distribuição das forças, embora possa causar a intrusão dentária. Já a união rígida, apresenta maior estresse e maior perda óssea na região dos implantes. Conclusão: o correto planejamento, embasado na biomecânica, assim como controles clínicos e rádio gráficos posteriores, são de suma importância para o sucesso do tratamento reabilitador protético...

Cleft lip and palate lead professionals to idealize unconventional prostheses to find the solution for the rehabilitation that becomes, oftentimes, complex. Totally implant-supported prostheses should be the treatment of choice, although there are cases in which the connection of teeth with implants is inevitable. Some authors advocate the rigid connection, others the non-rigid connection and still others do not recommend the implant-tooth connection. The risks related to this connection are the result of biomechanical differences between the structures involved, periodontal ligament and bone, and biomechanics of teeth and implants supported on the prostheses. Objective: this report presents a case of oral rehabilitation with a removable partial prosthesis on teeth connected to implants in a patient with cleft lip and palate in Hospital of Rehabilitation of Craniofacial Anomalies of Bauru. Method: case report. Results and Discussion: a 47 year old female patient, with incomplete post foramen cleft presenting the teeth 13, 23 and 27, which was extracted by periodontal problems, and two implants placed in regions of the teeth 16 and 26. The prosthetic rehabilitation treatment was the installation of a removable partial prosthesis with a bar-clip type of fit retained by 3 metal bars connecting teeth to implants through a tube screw system. The non-rigid connection demonstrates greater distribution of forces, although it can cause tooth intrusion...

Análise da utilização da união dente/implante e tipos de conexões: revisão de literatura / Analysis of the use of the tooth-implant union and types of connections: literature review

Após a divulgação do conceito de osseointegração por Brãnemark, baseado em anos de estudo, houve uma grande mudança na Odontologia moderna. Os tratamentos ganharam muitas variáveis no planejamento, normalmente mais estéticos e eficazes. Apesar da introdução dos implantes osseointegrados, com grande demanda e evolução da técnica, alguns fatores ainda limitam a colocação de um número adequado de implantes. Com isso, tem-se deparado com uma situação clínica de grande importância na Implantodontia: a restauração do edentulismo parcial utilizando pilares de dentes naturais unidos a implantes. O principal fator de preocupação ao se indicar a união dente/implante é a biomecânica, devido à diferença de absorção das forças oclusais pelos dois componentes distintos, dente e implante. Através de uma revisão de literatura, foram abordados os critérios biomecânicos dessa união, considerações sobre as formas de executá-la, as possíveis complicações e os achados clínicos das pesquisas. Embora os conceitos teóricos revelem problemas em potencial, os resultados clínicos apontam favoravelmente para o uso desse tipo de união. Segundo alguns profissionais, principalmente em segmentos curtos e com conexões rígidas, entretanto, o assunto é ainda bastante controverso.

After the popularization of the osseointegration concept from Branemark, based on years of study, there was a great turn in the modem dentistry. The treatments won many variation during prosthodontic planning related to aesthetics and efficacy. In spite of introduction of osseointegrated implants, technical developments and increase of indications, several factors still limit the use of an appropriate number of implants. With that, a critical situation in the Implantology: to use or not tooth-implant connection, and in using, what is the best way to do so. The main factor of relevance to indicate the tooth-implant connection is the biomechanics, due to the difference of absorption of the occlusal forces on the two different components, tooth and implant. Through literature review, the biomechanical criteria of this union, considerations of how to do it possible and the complications that could occur were discussed. Although the theoretical concepts reveal potentials problems, the clinical results appear favorable to the use of this type of union, mainly in short segments and with rigid connections.