Opinions Regarding Reuse or Replacement of Implant Prosthesis Retaining Screws: A Systematic Review

Purpose: To identify whether reuse or replacement is better for managing loose screws. Materials and Methods: An electronic search was performed utilizing PubMed, and a further manual search of the reference lists of relevant reviews and articles was conducted. Selected inclusion and exclusion criteria were used to limit the search. Results: The electronic and manual search provided 243 titles and abstracts. Fulltext analysis was performed for 98 articles, resulting in a total of 15 articles that qualified for inclusion in this study. All the included articles reported that loose screws were reused and retightened or were replaced by new screws. The time of screw loosening ranged from 1 month to 3 years after delivery. Available details of numbers and frequency of screw loosening permitted only limited analysis from very few articles. A total of 44 loose screws reported in two articles did not loosen again after retightening once. Conclusion: From the very limited available literature, it appears that retightening an occlusal screw or abutment screw is an acceptable procedure, as the evidence shows that retightened screws seem to remain tight. Replacement of screws as a routine procedure cannot be recommended. Routine assessment of screw tightness is recommended to minimize additional and more severe complications. Keywords: dental implant, screw loosening, screw-retained, systematic review