Academic literature on the topic 'Morse Taper Internal Connection'

The project focused on the application of the Morse-taper connection in implant dentistry, which was investigated both through laboratory and through clinical examination. Mechanical laboratory study Among the complications that can occur at dental implants, the fracture of any implant component is a relatively infrequent but clinically significant problem. Small diameter implants are at higher risk of such complication. The aim of this laboratory study was to compare the mechanical behavior of a 2.9 mm and a 3.3 mm diameter implant with a conical connection under standard static and dynamic conditions, following the ISO 14801:2017. Finite element analysis was performed to compare the stress distribution on the tested implant systems under a 300 N, 30° inclined force. Static tests were performed with a load cell of 2 kN; force was applied on the experimental samples at 30° with respect to the implant-abutment axis, with an arm of 5.5 mm. Fatigue tests were performed with decreasing loads, at 2 Hz frequency, until three specimens survived without any damage after 2 million cycles. The emergence profile of the abutment resulted the most stressed area in finite element analysis, with a maximum stress of 5829 MPa and 5480 MPa for 2.9 mm and 3.3 mm diameter implant complex respectively. The mean maximum load resulted 360 N for 2.9 mm diameter and 370 N for 3.3 mm diameter implants. The fatigue limit was recorded to be 220 N and 240 N respectively. Despite the more favorable results of 3.3 mm diameter implants, the difference between the tested implants could be considered clinically negligible. This is probably due to the conical design of the connection, which has been reported to present low stress values in the implant neck region, thus increasing the fracture resistance. Microbiological in vitro test Tissue inflammation around implants could be due to microbial colonization of the implant-abutment interface (IAI). The aim of the present in vitro study was to evaluate bacterial microleakage at the IAI in Morse-taper implant-abutment connections. A bacterial suspension containing A. actinomycetemcomitans, F. nucleatum, and P. gingivalis was inoculated into the internal cavity of ten implant-abutment samples with a Morse-taper internal connection. The samples were assembled using a calibrated beater, totally immersed individually into culture tubes, and incubated at 37°C. Turbidity analysis, real-Time PCR, and horizontal electrophoresis were performed at 24, 48 and 72 h. Performed tests were negative for every specimen, except two of them because of contamination during the manipulation of the components. Morse-taper implants rely on a frictional connection, which results in a very narrow implant-abutment space. This can account for the sealing capability of conical connections against bacterial microleakage. Although in literature no connection type was able to provide a complete bacterial seal at the IAI, Morse-taper connection implants showed less microleakage in comparison with other connection types. The present in vitro evaluation confirmed the sealing capability of Morse-taper connections in static conditions. Clinical study The third part of the project is a clinical observational prospective single-arm study on Morse-taper connection implants. The main objective of the study was be to evaluate the survival rate and the clinical and radiographic success of Morse taper connection implants, used for single-tooth and partial rehabilitations, and to assess the incidence of technical and biological complications. The following data were collected: • implant-related factors: implant type, length, and diameter • patient-related factors: age, gender, smoking status, systemic diseases, medications, history of periodontal disease, bruxism • cause of the initial tooth loss: aplasia, unerupted tooth, traumatic injuries, caries, periapical periodontitis, marginal periodontitis • site-related factors: implant position, bone quantity / quality following the Lekholm and Zarb classification (Lekholm and Zarb 1985) • prosthesis-related factors: prosthetic restoration extension (single crown, partial fixed denture), prosthetic restoration material (all-ceramic, metal-ceramic, resin). To evaluate the clinical and radiographic success of the implants used, the following parameters were recorded during follow-up visits, 3, 6, 18, 12 and 24 months after surgery: • Full-mouth plaque score % (FMPS%) • Full-mouth bleeding score % (FMBS%) • probing depth (PD) on the mesial, distal, buccal and palatal/lingual surfaces of the implants. The higher PD and the mean PD, measured as the average of four measured values, was considered for each implant. • Bleeding scores, assessed on the basis of this scale: 0) no bleeding; 1) bleeding on probing without redness and swallowing; 2) bleeding on probing with redness and swallowing; 3) spontaneous bleeding. • Plaque scores, assessed on the basis of this scale: 0) no plaque accumulation; 1) plaque accumulation revealed using a probe; 2) moderate accumulation of visible plaque/calculus; 3) high accumulation of visible plaque/calculus. • distance from the implant crown margin to the coronal border of the peri-implant mucosa (DIM) • width of keratinized mucosa (KM) • radiographic distance between the implant shoulder and the first crestal bone-implant contact (DIB), measured on intraoral peri-apical radiographs taken a Rinn alignment system • radiographic presence of continuous peri-implant radiolucency, measured on intraoral peri-apical radiographs taken a Rinn alignment system • Prosthesis function • Technical complications: implant fracture; abutment fracture; screw fracture; veneer fracture or chipping; metal framework fracture; abutment loosening; screw loosening; loss of access hole restoration. A total of 13 patients were treated with 41 implants. At the time of the last evaluation no implants failed, and all were successful. As for complications, no technical complication occurred. None of the implants showed signs of peri-implantitis, but a diagnosis of peri-implant mucositis was formulated in 3 patients, for a total of 8 implants. Bone resorption was consistent with the phisiological bone remodelling that occurs in the first year after loading. The regression analysis did not reveal any significant effect of any of the parameters on bone resorption, except for the history of periodontitis, which had a small but significant negative effect (p=0.47).

Problemas com desenho de conexões protéticas sobre implantes, microfendas, afrouxamento e, consequentemente, perdas das estruturas protéticas reabilitadoras são tópicos frequentes do estudo odontológico. Conexões do tipo Cone Morse, devido às suas características, diminuíram o índice desses problemas, abrindo uma nova perspectiva para o sucesso da prótese sobre implante. Contudo, ainda é frequente encontrar componentes que falham no desempenho, levando à falência da restauração, especialmente quando esses componentes não são bem ajustados, bem fixados ou, ainda, não possuem, na sua geometria, características suficientes para suportar as forças laterais e oclusais de um ciclo mastigatório. O objetivo deste estudo é avaliar a influência do jateamento com óxido de alumínio sobre a superfície externa dos componentes protéticos, separadamente e em conjunto, com um adesivo industrial, em uma tentativa de aumentar os valores de torque de abertura de componentes apertados em seu torque recomendado, pelo fabricante ou menor. Neste ensaio, foram utilizados 36 implantes da marca Straumann®, de 10mm de comprimento com diâmetro de 4,8 mm, os quais foram divididos em 6 grupos: Grupo 1 = controle, torque de 35 N.cm; Grupo 2 = superfície jateada com óxido de alumínio (# 320) e torque de 35 N.cm; Grupo 3 = superfície jateada com óxido de alumínio (# 320) e torque de 25 N.cm; Grupo 4 = superfície jateada com óxido de alumínio (# 100) e torque de 25 N.cm; Grupo 5 = superfície jateada com óxido de alumínio (# 320), aplicação de adesivo e torque de 25 N.cm; Grupo 6 = superfície jateada com óxido de alumínio (# 100), aplicação de adesivo e torque de 25 N.cm, que receberam componentes protéticos sólidos de 5,5 mm de altura, regulares e alterados. As modificações incluídas foram o jateamento com partículas de óxido de alumínio (100 e 320 micra) e o uso de Loctite® 277 como adesivo industrial. Os conjuntos implante-componente foram levados até uma máquina de controle de tração, Instron®, e, após a sua calibração, as amostras dos grupos foram apertadas em 35 e 25 N.cm, com um conjunto catraca-torquímetro, com checagem visual e registro no software acoplado à máquina de ensaio. Após trinta dias, os grupos foram levados à máquina novamente e o conjunto abutment-implante foi desapertado, agora somente com registro no software da máquina de ensaio. Os valores e porcentagens da diferença entre torque de aperto e desaperto foram avaliados estatisticamente, e comparados entre os grupos. Para todas as associações, o valor de p deveria ser menor ou igual 0,05, para relevância. O grupo Jateado 35 N.cm, 320 micra, não apresentou valores mais altos do que o grupo Controle no momento do torque de desaperto, assim como os grupos Jateados 25 N.cm 100 e 320 micra. Os grupos Jateados 25 N.cm, 100 e 320 micra, com adesivo, mostraram uma resistência por volta de uma vez e meia maior, no torque de desaperto do que o grupo Controle 35 N.cm.<br>Problems with design of prosthetic implant connections, microleakage,! loosening which leads to loss of rehabilitative prosthetic structures are frequent topics of dental study. Morse taper connections, due to its characteristics, decreased the rate of these problems opening a new perspective to the success of the prosthesis supported over implant. However, it is still frequent to find components that fail in performance leading to failure of restoration especially when these components are not well adjusted, tightened or do not have in its geometry enough characteristics to support the occlusal and lateral forces in a masticatory cycle. The aim of this study is to evaluate the influence of blasting with aluminum oxide on the outer surface of the prosthetic components separately and in conjunction with an industrial adhesive in an attempt to increase the opening torque values of components tightened on their recommended torque by the manufacturer or less, therefore allowing the dentist an early intervention in the prosthetic rehabilitation. In this test, 36 Straumann® implants of 10mm high and 4,8mm wide were used. They were divided into six groups: Group 1 Solid abutments control group - 35 N.cm tightened; Group 2 - Solid sandblasted abutments, 35 N.cm aluminum oxide 320 microns size particles; Group 3 - Solid sandblasted abutments, 25 N.cm aluminum oxide 320 microns size particles; Group 4 - Solid sandblasted abutments, 25 N.cm aluminum oxide 100 microns size particles; Group 5 - Solid sandblasted abutments, 25 N.cm aluminum oxide 320 microns size particles with glue application; Group 6 - Solid sandblasted abutments, 25 N.cm aluminum oxide 100 microns size particles with glue application, which received 5,5 mm high regular and modified solid abutments. The included modifications were sandblasting with aluminum oxide particles (100 and 320 microns) and the use of Loctite® 277 as an industrial adhesive. The samples were taken to a traction control test machine, Instron ®, and after calibration the group samples were tightened on 35 and 25 N.cm with a ratchet-wrench set with visual check. The data was recorded in a software coupled to the test machine. After thirty days the groups were brought again to the test machine and the samples were untightened. At this point the resulting data was recorded only in the testing machine software. The values and percentages of the changes between the tightening and loosening torques were recorded and compared among the study groups. For all associations a p-value < 0.05 was considered significant. The group blasted 35 N.cm, 320 microns did not show higher values than the control group at the time of loosening torque as well as groups blasted 25 N.cm 100 and 320 microns. The groups blasted 25 N.cm, 100 and 320 microns with adhesive showed a resistance around one and a half times greater in the loosening torque than the control group 35 N.cm.

In this master thesis the connection between the two major parts of an osseointegrated prosthesis system for lower limb amputees has been investigated by finite element (FE) analysis. The prosthesis system is developed by Integrum and the current design consists of a fixture, which is integrated in the residual bone, an abutment that penetrates the skin and an abutment screw that holds the parts together. The connection between the fixture and the abutment has a hexagonal section and a press-fit section that together form the connection. Due to wear and fracture problems it is desired to improve the connection. A tapered connection could be an alternative and three different taper angles, the effect of the length of the taper and the smoothness of the outer edge of a tapered fixture have been investigated. The results show that the taper has potential to function well and that a longer connection will give lower stresses in the system, but further investigations are needed.

O objetivo principal deste estudo foi realizar uma revisão sistemática sobre a integridade mecânica das conexões cone Morse de implante em relação à presença de microgap e manutenção do torque. Uma ampla pesquisa eletrônica foi realizada nos bancos de dados PubMed, Embase e Medline com as palavras chaves: dental implant” e “dental abutment” e (“conical” ou “taper” ou “cone”). “removal torque” e “Morse Taper”, “torque loss” e “micro gap size” Estudos in vitro demonstraram que os pilares cônicos têm melhor desempenho, no que diz respeito ao selamento bacteriano e a manutenção do torque e estabilidade do pilar, do que os pilares não cônicos. Estudos in vivo mostraram que as taxas de sucesso e sobrevivência dos sistemas de implantes cone Morse comparadas aos outras, são quase comparáveis; porém os implantes com conexão cone Morse mostraram menor perda ossea marginal. Conclui-se , com esta revisão sistemática, que o uso de implantes com conexões cone Morse parece ser mais vantajoso, pois de mostraram ter melhor desempenho em termos de estabilidade mecânica e selamento bacteriano.<br>The main aim of this study was to carry out a systematic review on the mechanical integrity of Morse taper implant-abutment connections in relation to the presence of micro gap and torque maintenance. A broad electronic search was conducted using PubMed, Embase, and Medline databases with the logical operators: “dental implant” AND “dental abutment” AND (“conical” OR “taper” OR “cone”). “Removal torque” and “Morse Taper”, “Torque” and “micro gap size” In vitro studies demonstrated that conical abutments are more advantageous than non-conical abutments, and appeared to be superior in terms of bacterial seal performance, torque maintenance, and abutment stability. In vivo studies showed that the success and survival rates for conical and non-conical implant-abutment systems are almost comparable; however, the results indicated that, conical connection implants are more favourable as the majority of cases showed less marginal bone loss around. This systematic review points out that the use of conical implant–abutment connections seem to be more advantageous as they clearly showed better performance in terms of mechanical stability and bacterial seal.