Current Treatment Strategies for Peri-implant Diseases

Peri-implant mucositis is a reversible condition of the soft tissues around an implant and implants exhibiting inflammation limited to soft tissue and implants with peri-implant mucositis are sometimes described as “ailing” implants.³³ Clinical signs of peri-implant mucositis include presence of bleeding on probing, swelling of the peri-implant mucosa, increase of probing depth (pseudopockets), and/or erythema of surrounding tissues.⁸⁹ Peri-implantitis is a bacterially-initiated, inflammatory condition of the tissues around osseointegrated implants characterized by progressive loss of supporting bone that is verified by radiographs and clinical signs of inflammation (bleeding and/or suppuration on probing).⁹⁰ Implants with peri-implantitis are often categorized as “failing” implants and when these implants are refractory to treatment and/or present with clinical mobility they are classified as “failed.”⁹¹ Implants can fail at various stages in treatment and function. When implants fail due to lack of initial osseointegration, this is referred to as early implant failure. Early failures are influence by patient-specific impaired healing responses, acute infection, premature loading, and/or surgical trauma.⁹² Late failure of implants occurs after the initial phase of osseointegration, remodeling and loading. Late failures are associated with occlusal overload, fixture or prosthetic fracture, and peri-implant disease.⁹³ Peri-implantitis has been seen in a mean of 22% of implants in place and has been noted in 10% of implants and 20% of implant patients within 10 years of surgical implant placement.^3-6,90 When either peri-implant mucositis or peri-implantitis is detected, it is imperative to initiate therapeutic intervention as soon as possible.¹¹

Successful therapy to treat peri-implantitis can be assessed in a number of ways. Ideally, resolution of disease would mean absence of clinical inflammation (bleeding on probing) and a lack of progressive bone loss and/or regeneration of lost tissues.^44,45 At sites with peri-implant mucositis, biofilm control and adequate implant maintenance can reestablish implant health.^55,94 A systematic review examining various methods to treat peri-implant disease included studies that reported on implant loss, mean probing depth, % of sites or implants with bleeding and/or suppuration on probing, and radiographic bone levels at 12 months (or longer) following treatment. Successful treatment outcomes were defined as: implant survival with no mean probing depths ≥ 5 mm and no further bone loss 12 months after treatment.^44,45 Non-surgical treatment included debridement using manual or ultrasonic instruments, laser treatments in conjunction with local debridement, and adjunctive systemic or local application of antimicrobial agents.^44,45 Successful treatment outcomes for nonsurgical therapy ranged from 0%-84%.^95-97 Generally, these therapies were not successful at sites with initial peri-implantitis demonstrating extensive bone loss and/or deep probing depths.⁹⁵ At these sites, additional surgical intervention has been demonstrated to be necessary.⁹⁵ Surgical treatment of peri-implantitis included regenerative protocols, access surgery, and resective surgery.^98-106 The success rates for regenerative surgery ranged from 0-100%^{98-102,104,105} and included treatments of bone grafting without membrane using xenograft, autograft, or combination,^99,100 using non-resorbable membranes alone,⁹⁸ resorbable membrane in combination with bone graft materials,^99,100 or bone grafting in combination with subepithelial connective tissue graft.^101,102,104 Non-resorbable membranes included in this analysis had a high rate of exposure and did not demonstrate significant clinical improvements.⁹⁸ Access surgery using curettes for debridement of implant surface and saline soaked gauze for surface decontamination had success rate of 88% in achieving implant stability over time.¹⁰³ Resective surgery alone demonstrated success rate of 0% due to bone loss over 3 years, while implantoplasty with resective surgery had success rate of 100% and bone level remained unchanged over 3 years.^105,106 However, few implants were included in each group of treatment modalities and definitive identification of a superior therapy cannot be made from the current data.