Salivary contamination during implant placement: effects on titanium surface properties and early osseointegration- a systematic review

Dental implants demonstrate high long-term success rates; however, contamination of the implant surface by saliva during implant placement surgery is a common intraoperative event. Experimental studies suggest that saliva contamination may alter the physicochemical properties of titanium surfaces, impair early cellular responses, and adversely affect the initial phase of osseointegration. This systematic review aimed to evaluate the effects of saliva contamination occurring during dental implant surgery on titanium surface characteristics, early biological responses, and the osseointegration process. Electronic searches were performed in PubMed, Web of Science, Scopus, and Google Scholar databases covering the period from January 2000 to January 2026. A total of 54 studies (in vitro, in vivo, and clinical) meeting the predefined PICO (Population, Intervention, Comparison, Outcome) criteria were included. The methodological quality of the included studies was assessed using the Quality Assessment Tool for In Vitro Studies in Dentistry (QUIN) tool for in vitro studies and the Systematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk-of-bias tool for animal studies. Saliva contamination induces rapid protein adsorption on implant surfaces, leading to a marked reduction in surface wettability and surface energy. These changes are associated with decreased osteoblast adhesion and reduced alkaline phosphatase (ALP) activity, thereby negatively affecting early bone healing and osseointegration. The formation of a salivary pellicle may, under certain conditions, promote bacterial adhesion, and endotoxin-related surface alterations may persist even after surface cleaning procedures. None of the investigated decontamination methods, including saline irrigation, antimicrobial photodynamic therapy, or air-polishing, were able to fully restore the original bioactive surface characteristics. Current evidence consistently indicates that saliva contamination may adversely affect early biological responses and the osseointegration process by altering titanium surface properties, particularly surface wettability and surface energy. However, as these data are largely derived from in vitro and animal models, caution is warranted when extrapolating the findings to clinical practice. The current literature does not provide sufficient clinical evidence to justify the routine replacement of implants following short-term intraoperative saliva contamination. Considering that no decontamination method has been shown to fully restore the original bioactive surface characteristics, prevention of contamination appears to be a more reliable strategy than post-contamination decontamination protocols. Future studies should focus on investigating the long-term effects of saliva contamination on implant survival using standardized, well-designed prospective clinical protocols.