Abstract. As dental implants have become a mainstream solution for tooth replacement, attention has increasingly turned to the biological complications that can affect them over time. Peri-implant diseases — comprising peri-implant mucositis and peri-implantitis — are inflammatory conditions of the soft and hard tissues surrounding osseointegrated implants. Peri-implantitis, the more advanced form, is characterized by inflammation of the peri-implant mucosa together with progressive loss of supporting bone, and it represents a leading cause of late implant failure. This review summarizes the current understanding of the definitions, epidemiology, etiology, risk factors, diagnostic criteria, and management of peri-implant diseases, with an emphasis on the prevention strategies most relevant to clinical practice.
Definitions and Disease Spectrum
Peri-implant diseases exist on a continuum analogous to the relationship between gingivitis and periodontitis around natural teeth. Peri-implant mucositis describes a reversible inflammatory lesion confined to the soft tissue surrounding an implant, with bleeding on gentle probing as its defining clinical feature and no associated loss of supporting bone. Peri-implantitis is a plaque-associated pathological condition in which the inflammation extends beyond the soft tissue and is accompanied by progressive loss of the marginal bone that supports the implant. The 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions established consensus case definitions for these entities, framing peri-implantitis as a site exhibiting bleeding and/or suppuration on probing, increased probing depths relative to baseline, and radiographic bone loss [1, 2].
Epidemiology
Peri-implant diseases are common. In a frequently cited systematic review and meta-analysis, Derks and Tomasi reported weighted mean prevalences of 43% (95% CI: 32–54%) for peri-implant mucositis and 22% (95% CI: 14–30%) for peri-implantitis at the patient level [3]. Reported figures vary widely across studies — from 19% to 65% for mucositis and from 1% to 47% for peri-implantitis — reflecting heterogeneity in case definitions, diagnostic thresholds, implant function time, and study populations. Meta-regression has shown that peri-implantitis prevalence rises with longer function time and falls as the threshold used to define bone loss increases [3]. Taken together, the evidence indicates that a substantial proportion of implants will develop some degree of peri-implant inflammation over their service life, underscoring the importance of long-term monitoring.
Etiology and Pathogenesis
The primary etiological factor in peri-implant disease is the accumulation of a bacterial biofilm at the implant–mucosa interface. As with periodontitis, the host inflammatory response to this microbial challenge drives tissue destruction. Experimental and clinical evidence supports a cause-and-effect relationship between biofilm accumulation and the development of peri-implant mucositis, which is reversible when the biofilm is removed [4]. If inflammation persists, dysbiosis of the peri-implant microbiome and a sustained host response can lead to the apical extension of the lesion and progressive bone loss characteristic of peri-implantitis. Notably, the peri-implant lesion in established peri-implantitis tends to be larger and less self-limiting than the comparable lesion around natural teeth, which may contribute to its frequently progressive, non-linear course.
Risk Factors and Indicators
Several factors have been associated with an elevated risk of peri-implantitis. A history of periodontitis is among the most consistently reported, with patients who have a background of periodontal disease showing higher rates of peri-implant breakdown. Poor plaque control and lack of supportive maintenance are strongly linked to disease onset and progression. Cigarette smoking is a well-documented risk factor, and poorly controlled diabetes has been associated with greater susceptibility, consistent with its role in periodontal disease. Local factors also contribute: excess residual cement from cement-retained restorations, implant malposition that hinders hygiene access, and a deficiency of keratinized peri-implant mucosa have all been implicated in some studies. Because several of these indicators are modifiable, their identification carries direct clinical relevance for both prevention and treatment planning [1, 4].
Diagnosis
Diagnosis rests on a combination of clinical and radiographic assessment. Gentle peri-implant probing to evaluate bleeding, suppuration, and probing depth is fundamental; bleeding on probing is the cardinal sign of peri-implant mucositis, while increasing probing depth over time signals possible disease progression. Radiographs are required to assess marginal bone levels, and comparison against a baseline image taken at the time of restoration is ideal. According to the 2018 consensus case definitions, in the absence of baseline data, peri-implantitis may be diagnosed on the basis of bleeding and/or suppuration on probing, probing depths of 6 mm or greater, and bone levels 3 mm or more apical to the most coronal portion of the intraosseous part of the implant [2]. Establishing baseline records at the time of prosthesis delivery is therefore strongly advised to enable accurate longitudinal monitoring.
Management
Management is guided by the stage of disease. Peri-implant mucositis is treated primarily through non-surgical biofilm removal and reinforcement of patient-performed hygiene; because the lesion is reversible, effective treatment at this stage is the most reliable way to prevent progression to peri-implantitis. Established peri-implantitis is more difficult to resolve. Non-surgical mechanical debridement, sometimes supplemented by adjuncts such as local antimicrobials, air-polishing, or laser therapy, can reduce inflammation but is frequently insufficient on its own to fully resolve established peri-implantitis. Surgical approaches — including access flap surgery for decontamination, resective procedures to reduce pocket depth, and regenerative techniques aimed at reconstructing lost bone in suitable defects — are often required, with decontamination of the implant surface being a central and technically demanding objective. Treatment outcomes are variable, and disease recurrence is possible, which reinforces the priority of prevention and early intervention [4].
Prevention and Supportive Care
The most effective strategy against peri-implantitis is prevention. Optimizing modifiable risk factors before implant placement — treating existing periodontal disease, supporting smoking cessation, and improving glycemic control — establishes a more favorable biological environment. Prosthetic design that permits adequate hygiene access and careful removal of residual cement reduce local risk. After restoration, enrollment in a structured program of supportive peri-implant maintenance, with professional biofilm removal and reinforcement of home care at regular intervals, is associated with lower incidence of disease and is widely regarded as essential to long-term implant health. For a patient-oriented overview of implants and their long-term care, see our guide to dental implants and replacing missing teeth.
Conclusion
Peri-implant diseases are common biological complications of dental implant therapy, with peri-implantitis representing a significant cause of late implant failure. Current evidence frames these conditions as biofilm-associated inflammatory diseases whose onset and progression are modulated by identifiable, often modifiable, risk factors. Because established peri-implantitis remains challenging to treat predictably, the weight of clinical evidence favors prevention through risk-factor management, sound prosthetic design, accurate baseline documentation, and consistent supportive maintenance. Ongoing research continues to refine treatment protocols and clarify the long-term outcomes of the various therapeutic approaches.
References
1. Berglundh T, Armitage G, Araujo MG, et al. Peri-implant diseases and conditions: Consensus report of workgroup 4 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. J Clin Periodontol. 2018;45(Suppl 20):S286–S291.
2. Renvert S, Persson GR, Pirih FQ, Camargo PM. Peri-implant health, peri-implant mucositis, and peri-implantitis: Case definitions and diagnostic considerations. J Periodontol. 2018;89(Suppl 1):S304–S312.
3. Derks J, Tomasi C. Peri-implant health and disease. A systematic review of current epidemiology. J Clin Periodontol. 2015;42(Suppl 16):S158–S171.
4. Schwarz F, Derks J, Monje A, Wang HL. Peri-implantitis. J Periodontol. 2018;89(Suppl 1):S267–S290.
This article is intended for general educational purposes and does not constitute individual medical or dental advice. If you have questions about implant care or peri-implant health, the team at Fridman Family Dental Care in Valencia, CA is happy to help — contact us to schedule a consultation.
