RESUMO
This in vitro study evaluated the 6-month fatigue retention provided by 5 paired overdenture attachments placed at 3 different interimplant distances (19, 23, and 29 mm). Mean fatigue retention was calculated for each attachment type and compared with the retention produced by the other attachments tested and the initial retention values published earlier. Interimplant distance was found to play a significant role only in the retention of the Hader bar with red and yellow clips. A significant reduction in retention values was observed for 4 of 5 attachment types.
Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Retenção de Dentadura , Revestimento de Dentadura , Dente Suporte , Ligas Dentárias/química , Materiais Dentários/química , Retenção de Dentadura/classificação , Retenção de Dentadura/instrumentação , Prótese Total Inferior , Ligas de Ouro/química , Humanos , Magnetismo/instrumentação , Teste de Materiais , Plásticos/química , Aço Inoxidável/química , Estresse Mecânico , Titânio/químicaRESUMO
PURPOSE: This in vitro study aimed to investigate the influence of (1) the interimplant distance and (2) the type of attachment on the retention of mandibular overdentures on 2 implants. MATERIALS AND METHODS: Three stone casts were fabricated, each with 2 implant analogues embedded at distances of 19, 23, and 29 mm apart. Three different interchangeable mandibular overdenture attachments were secured onto the analogues: Hader bars, ball abutments, and stainless steel keepers for new generation neodymium-iron-boron magnets. In total, 45 groups of paired attachments were tested for initial vertical peak tensile load at the 3 interimplant distances. RESULTS: Interimplant (interclip) distance played a significant role only in the retention produced by the Hader bar/red clip configuration. At 19 and 23 mm, the ball/socket attachments were statistically more retentive than the yellow clips, white clips, and magnets, but not compared to the red clips. At 29 mm, the ball abutments showed statistical superiority compared with all other attachments. Mean clinical intercanine distance for conventional full dentures was 22.88 mm. CONCLUSION: Interimplant distance can affect the initial retention of mandibular overdentures on 2 implants depending on the type of attachment used. For a predetermined interimplant distance, attachment performance varies greatly.
