Cluster behavior in dental implant failure - A scoping review

To provide an overview of cluster behavior in dental implant failure including the reported prevalence in modern roughened surface implants as well as the risk factors associated with cluster failures.

An electronic search for articles in the English language literature published from January 1, 2000, to March 8, 2023, was performed using PubMed, Embase, Dentistry and Oral Sciences, ProQuest, and Central search engines. Using a standardized systematic search process and predetermined inclusion and exclusion criteria in three stages, the final list of selected articles reporting on cluster behavior in dental implant failure was obtained. Cluster behavior was defined as the failure of two or more implants in the same patient within a 2-year period irrespective of the site. Data from the selected articles were reviewed, critically analyzed, interpreted, and reported.

The initial electronic search resulted in 948 titles. After applying inclusion and exclusion criteria, the systematic search process resulted in five clinical studies reporting data on cluster behavior of dental implant failure with modern roughened surfaces. These five studies reported on a total of 9986 implants with 858 reported failures (early and late) over varying periods. Out of the 858 implant failures, 217 implants (25.2%) exhibited cluster behavior. The overall prevalence of cluster behavior of modern roughened surface implant failure was 2.1%.  The most common location risk factors reported were posterior maxilla, history of previous implant failures, poor bone quality, and occlusal overload.

Cluster behavior occurs in 25% of modern roughened surface implant failures which is significantly less than machined surface cluster implant failures. Nevertheless, the overall prevalence of cluster pattern of implant failure of modern roughened surface implants is reasonably low at 2%.