Clinical outcomes and supragingival microbiota analysis around dental implants and teeth in patients with a history of periodontitis: a preliminary study of 6 months follow-up

Objectives: To investigate the supragingival microbiome surrounding dental implants and neighbouring tooth in periodontitis history and periodontally healthy patients.

Methods: Subjects with a history of periodontitis (test) and periodontally healthy subjects (control) received one of two types of dental implants with different surface characteristics: sandblasted acid-etched (SLA) or precision dimension laser-treated (PDL). Periodontal clinical measurements were collected at baseline (V₁), 3 months after implant placement (V₄), at zirconia crown placement (V₆) and 3 months after zirconia crown placement (V₈). Supragingival bacterial microbiota was studied using Illumina MiSeq sequencing.

Results: Supragingival microbial community on SLA implants in test group significantly differed to control group at V₈ (p < 0.05). A longitudinal shift displaying microbial dysbiosis occurred on SLA implants (p < 0.05) and adjacent teeth (p < 0.05) among test patients from V₆ to V₈. On PDL implants and the adjacent tooth, no significant difference between test and control groups from V₆ to V₈ (p > 0.05). Co-occurrence network in test group of SLA implants and the adjacent tooth at V₈ showed increased disease-associated bacteria and reduced health-associated bacteria. Health-associated bacteria were dominant in control group of SLA implants at V₈.

Conclusion: The surface characteristics and prosthetic components of dental implants may be important risk factors in patients with a history of periodontitis.

Clinical relevance: Dysbiosis of supragingival microbiome may predispose dental implants to peri-implant diseases. Thus, a strict supportive periodontal care plan is imperative to prevent early onset of biological complications.