Abstract
Introduction
Treatment of peri-implantitis aims to remove biofilm on the surface of dental implants. A wide range of treatment methods are employed in a surgical or non-surgical approach to achieve this goal. However, it is currently unclear which approach is most effective for the decontamination of the implant surface or how the bony defect morphology around the dental implant affects the decontamination efficacy.
Objectives
This in vitro study aimed to evaluate how surgical and non-surgical approaches to different mechanical implant surface decontamination methods affect their efficacy and investigate how these are affected by the morphology of the bony defect surrounding the dental implant. Subsequent changes to the implant surface following decontamination were also explored.
Methods and Materials
One hundred and eight implants were first stained with indelible ink to simulate biofilm. The implants were evenly divided into surgical and non-surgical groups. Under each approach, the implants were further divided by treatment methods (ultrasonic device with metal tip (USM), ultrasonic device with PEEK tip (USP), and air-polishing with erythritol powder (PF)) and then by defect configuration (intraosseous semi-circumferential (Class Ib), intraosseous circumferential (Class Ie), and suprabony (Class II) defects). Each implant was instrumented by one operator (W.C.) under standardised conditions. The amount of residual ink was evaluated using an imaging software to assess the efficacy of mechanical decontamination methods and the subsequent changes to the implant surface were evaluated using an optical profilometer and scanning electron microscope. Changes to the implant surface chemical composition were also assessed using energy-dispersive X-ray spectroscopy.
Results
The surgical approach resulted in significantly less residual ink than the non-surgical approach (p < 0.001). All surgical treatment methods performed similarly (p = 0.314); however, the non-surgical approach with USP resulted in significantly higher residual ink than USM (p = 0.002) and PF (p < 0.001). When comparing each treatment method by surgical and non-surgical approach, significant differences were noted for USM (p < 0.001) and USP (p < 0.001) in favour of the surgical approach, but no significant differences were found with PF (p = 0.960). The same trend was observed when the efficacy of each treatment method was assessed at different defect configurations. The efficacy of mechanical decontamination methods was influenced by both the surface of the implant being instrumented and the morphology of the defects. PF performed the best on non-contained surfaces, particularly for Class II defects, but generally performed the worst on mesial surfaces. USM performed modestly in all defects and surfaces and their efficacy appeared to be affected more by access. USP had the poorest performance, especially on distal surfaces in all defects.
Implant surfaces treated by USM had severe morphologic changes, while with USP, a slight change with mild burnishing on the implant threads was found. PF resulted in the least changes with no significant changes noted on the implant surface. Compared to a non-contaminated implant surface, Sa and Sz values of the implant surface treated by USM were significantly lower (both p < 0.001). For USP, Sa was significantly lower (p < 0.001) but not Sz values (p = 0.422) compared to pristine implants. PF showed similar Sa (p = 0.228) and Sz values (p = 0.613) to pristine implants.
Conclusions
Surgical access resulted in improved implant surface decontamination efficacy compared to the non-surgical approach. The treatment method was a factor which influenced the quality of mechanical decontamination and the use of USP resulted in the poorest outcomes out of the mechanical decontamination methods assessed. The presence of bony walls in a defect was found to negatively influence the efficacy of decontamination.
With regards to implant surface changes, USM resulted in the most significant changes when assessing the implant surface both qualitatively and quantitatively. All treatment methods resulted in a change in implant surface chemistry.