To splint or not to splint oral implants in the implant-supported overdenture therapy? A systematic literature review

The objective of this systematic review was to assess the influence of splinted and unsplinted oral implants in the mandibular and maxillary implant-supported overdenture therapy, concerning the implant survival, the peri-implant parameters, the prosthetic complications and the patient satisfaction. An electronic MEDLINE search complemented by manual searching was conducted to identify randomized clinical trials, prospective and retrospective cohort studies on implant-supported overdentures with a mean follow-up of at least 3 years. Twelve studies from an initial yield of 1022 titles were finally selected and data were extracted. After an observation period of more than 3 years, there was no difference in implant survival rates between splinted and unsplinted design. From most of the investigations included in this study, it was mentioned that the unsplinted design needs more prosthetic maintenance. In more of the studies that were dealing with the satisfaction of the patients wearing implant-supported overdentures, no significant difference in the preference of the patients was reported. No significant difference in the peri-implant outcome between splinted and unsplinted design was found. Within the limits of this systematic review, it is concluded that there was no significant difference between the two different designs of implant-supported overdentures with respect to the soft tissue health status or patient satisfaction, although the bar-supported overdentures have been shown to need less prosthetic maintenance.