Document Type : مقاله مروری

Abstract

Introduction: Implant-supported overdentures have attained a special place as a successful alternative to conventional complete dentures. One of the most necessary repair procedures is relining to improve overdenture fit with underlying mucosa, particularly in the first year after delivery. The purpose of this study is to review various methods of relining in two types of implant-supported overdentures (ball and bar attachments).
Search strategy: All the relevant articles indexed in Pubmed from 1994 to 2012 were searched for the purpose of this review, using the following key words: reline, rebase and implant-supported overdentures. In ball attachment-supported overdentures we can use “abutment level” reline method with or without removal of the old cap during impression taking and then put the new caps directly (chair side) or indirectly in place. Of course, in the direct method we should overcome problems like holding the retentive caps in a specific direction and preventing penetration of acrylic resin into the undercuts. Another method for relining these overdentures is to use open impression coping and perform fixture level impression taking. Most of the relining methods of bar attachment-supported overdentures are based on direct or indirect clip attachment to denture base (taking an impression of the residual ridge and bar and use of open impression coping and a long waxing screw). In most of the relining methods which have been suggested for bar attachment-supported overdentures, it is not possible to accurately register the anatomic form of soft tissues under the bar attachment.
Conclusion: Clinical stages of relining in ball attachment-supported overdentures are probably simpler and less common than bar attachment overdentures. In these methods it is necessary to check occlusal contacts and correct them if necessary, like all the relining methods of complete denture and then remove a thin layer of denture inner surface, denture borders and undercuts.
 
Key words: Implant-supported overdenture, Rebase, Reline.