Sistemas de attachments empregados em overdentures sobre implantes: revisão de literatura

Abstract

One of the main forms of treatment for edentulism is conventional full dentures. However, complaints related to the lack of stability and retention of the lower denture are not uncommon, which considerably affects the patient's masticatory function and his satisfaction with the rehabilitation treatment. This scenario justifies the clinical significance of management with mandibular overdentures. The retention of these prostheses is improved by the use of attachment systems attached to the implant, of which the most commonly used are o'rings and bar-clip fittings. This review aimed to compare these two fitting systems in the literature regarding the parameters of retention, patient satisfaction, masticatory performance and maintenance requirements. Therefore, with the search terms "Denture, Overlay" AND "Denture Retention" and (ball attachments) AND (clip bar), the Pubmed, Bireme and Periódicos Capes databases were searched for randomized clinical studies from the last 12 years, in English and that addressed the surgical-prosthetic intervention of overdentures retained by two interforaminal implants with the use of at least one of those systems. From the data from 10 studies, it was possible to consider that the loss of retention of these two types of attachments has different aspects, since in the o'rings the decrease in retention is more linear and is influenced by factors such as the material that makes up its matrices , as well as the implant system integrated with it. In contrast, the bar-clip system undergoes greater retention in its retentiveness in the first months of use and, therefore, stabilization occurs. Significant differences were not observed between the two retainers in terms of patient satisfaction and chewing performance. However, these two aspects, when related to the function of overdentures, are superior to those associated with the use of conventional prostheses. In addition, the same elements that influence the evolution of retention also operate in the prosthetic maintenance requirements, with o'rings requiring more frequent repairs. However, for these findings to be fostered, there is a need for a greater number of cross-over clinical studies that evaluate these attachments prospectively.