Peri-implant mucositis is a frequent biological complication in patients rehabilitated with dental implants, primarily resulting from bacterial biofilm accumulation and the subsequent inflammatory response of the peri-implant soft tissue. It is regarded as the reversible precursor of peri-implantitis and, if left uncontrolled, may progress to irreversible bone loss around the implant. In patients rehabilitated with screw-retained full-arch implant-supported prostheses (All-on-4, All-on-6, or All-on-X), the fixed prosthesis cannot be removed by the patient and its design limits access to the peri-implant tissues, making effective home plaque control particularly difficult.
Supportive peri-implant care remains the mainstay of management; however, its effectiveness depends heavily on the patient's ability to maintain plaque control between professional maintenance visits. Adjunctive, non-antibiotic measures that can be applied daily at home are therefore of interest. Dual-light antibacterial photodynamic therapy, which combines antimicrobial photodynamic therapy with antibacterial blue light, provides a repeatable bactericidal effect without inducing antimicrobial resistance and has recently become available in a commercial home-use device.
This study is designed as a two-arm, parallel-group, single-blind pilot randomized controlled trial to evaluate the clinical and microbiological effects of adjunctive home-use dual-light antibacterial photodynamic therapy in patients with peri-implant mucositis around screw-retained full-arch implant-supported prostheses. Eligible participants will be recruited from the High-Tech Departments 1 and 2 of the Ho Chi Minh City Hospital of Odonto-Stomatology. All participants will receive standardized supportive peri-implant care and will then be randomly assigned in a 1:1 ratio to one of two groups: an intervention group that additionally performs home-use dual-light therapy daily for four weeks, or a control group that receives supportive peri-implant care alone. Randomization will use a software-generated block sequence prepared by an independent person, with allocation concealed by sequentially numbered, opaque, sealed envelopes.
Clinical parameters including bleeding on probing and peri-implant probing depth will be recorded at baseline, at two weeks, and at four weeks. Subgingival samples will be collected and analyzed by real-time polymerase chain reaction (qPCR) to quantify the levels of four periodontal pathogenic bacteria: Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Fusobacterium nucleatum. Adherence to the home-use protocol will be monitored using a daily patient diary, and structured questioning at each follow-up visit.
Clinical measurements and microbiological sampling will be performed by a single calibrated examiner who is blinded to group allocation, in order to minimize measurement bias, and standardized oral hygiene instructions will be provided to all participants throughout the study period. As this is the first study of dual-light antibacterial photodynamic therapy in this population, no reliable prior data are available for an a priori power calculation; the study is therefore conducted as a pilot trial in line with the CONSORT 2010 extension for pilot and feasibility trials. The collected data will be analyzed to determine differences in peri-implant inflammation, probing depth, and subgingival bacterial load between the two treatment modalities. The findings are expected to provide preliminary, evidence-based insights into the potential benefit of home-use dual-light antibacterial photodynamic therapy as an adjunct to supportive peri-implant care, and to inform the design of a future definitive trial.