Strategies to achieve fit in implant prosthodontics: A review of the literature

Purpose: This paper reviews the literature on advanced strategies that atte mpt to improve fit in implant prosthodontics with reference to the concept of the "distortion equation." Materials and Methods: The majority of the ar ticles reviewed were either clinical or technique articles that advocated s trategies to improve fit in implant prosthodontics. A limited number of ret rospective and prospective clinical trial studies were included as they rel ated to the topic. Reviewed articles were limited to those that addressed a dvanced strategies to improve fit. All of the scientific studies included i n this review used an in vitro experimental design. The advanced strategies were categorized into methods that address intraoral indexing and methods that use the implant master cast. Results: Relatively few methods have been scientifically proven to improve fit in implant prosthodontics. Most of th e tested strategies still resulted in a slight misfit of the frameworks to the implant abutments/analogues. Conclusion: Multiple factors preclude that the concept of "passive fit'' can be achieved in implant prosthodontics, e ven with the use of advanced strategies. The use of meticulous, accurate im plant prosthodontic procedures and the appropriate use of advanced strategi es continue to be the recommended means of achieving precise fit of the imp lant prosthesis to the intraoral abutments.