Current understanding of the etiology, diagnosis, treatment, and management of peri-implant diseases: a narrative review for the consensus report of the Korean Academy of Periodontology

Abstract

Over the past few decades, dental implants have been successfully utilized to replace teeth lost due to periodontal disease and other conditions. However, similar to natural teeth, dental implants are vulnerable to inflammatory peri-implant diseases, which can compromise their long-term viability. This review aims to summarize the current understanding of peri-implant diseases and discuss effective strategies for their diagnosis, treatment, and long-term management. Evidence related to peri-implant diseases was categorized and reviewed in 4 sections: 1) definition, prevalence, and classification; 2) risk indicators and etiological factors; 3) diagnostic criteria; and 4) treatment protocols for peri-implant diseases. The prevalence of peri-implant mucositis and peri-implantitis is significant, affecting 43% and 22% of implant cases, respectively. Key risk factors include poor oral hygiene, a history of periodontitis, and systemic conditions such as diabetes and smoking. The outcomes of treatment are influenced by the design of the implant prosthesis and the condition of the surrounding soft tissue. Management strategies include: 1) non-surgical treatment for implants diagnosed with peri-implant mucositis; 2) comprehensive treatment, which involves both mechanical and chemical debridement and surgical access, for implants affected by peri-implantitis; and 3) removal of failed implants, followed by the restoration of pre-existing peri-implant bone defects. Managing peri-implant diseases necessitates a comprehensive approach, encompassing risk assessment, tailored treatment planning, and stringent maintenance protocols. Regular follow-ups and patient education are critical for preventing disease recurrence and ensure the long-term success of implant therapy.

INTRODUCTION

For decades, dental implants have been effectively utilized to replace missing teeth. The first long-term observational study on the survival of implants placed in edentulous areas to support fixed dental prostheses was published in the early 1980s [1]. Since then, the use of implants has expanded to include both partially edentulous areas and single missing teeth. With increasing life expectancy and an aging population, we are now in an 'era of widespread implant therapy.' In Korea, where over 20% of the population is aged 65 and older, more than 8.7% of older adults benefit from dental implant treatments provided through the National Health Insurance [2]. The increasing prevalence of these implants, particularly among older adults, presents a dual challenge: managing the higher costs of long-term care due to peri-implantitis and addressing the significant impact on patient quality of life [3]. Modern implants offer high durability and aesthetic appeal but also bring an economic burden due to their maintenance. This highlights the importance of developing comprehensive treatment strategies that ensure the long-term viability of implants while optimizing patient outcomes through preventive measures and effective complication management. These strategies are essential for maintaining healthcare efficiency and improving the daily lives of patients affected by peri-implant diseases.

Dental implants require successful osseointegration at the bone-implant interface and soft-tissue integration in the transmucosal region, all within an oral microenvironment filled with pathogenic bacteria. This presents a significant challenge for achieving initial stability and ensuring the long-term viability of the implants, especially in patients with complicating factors such as advanced age, smoking habits, or diabetes [4]. In general, peri-implantitis progresses more rapidly and unpredictably compared to periodontitis, and it also yields less predictable treatment outcomes. This issue stems from the parallel alignment of collagen fibers around the implants, which impairs the mucosal seal that serves as a biological barrier. Additionally, the complex surface characteristics of the implant fixture, including thread structures and rough surfaces, complicate effective decontamination and diminish the likelihood of treatment success [5].

This paper provides an overview of the current understanding of peri-implant disease, including its prevalence and the risk factors that contribute to its progression. Additionally, it outlines the diagnostic criteria and treatment protocols for peri-implant disease, drawing on key consensus reports published to date.

SUMMARY STATEMENTS IN THE AREAS OF PERI-IMPLANT DISEASE PREVALENCE, CLASSIFICATION, AND DEFINITION

How can implant complications be classified?

Early implant complications typically involve the failure of osseointegration between the implant surface and the alveolar bone. This failure can be attributed to factors such as inappropriate surgical techniques, various types of surgical trauma, poor bone quality at the surgical site, and infection. Numerous studies have highlighted the significant impact of the surgeon's expertise on the rate of early implant failures [6,7,8,9]. Complications following prosthesis placement can be categorized into biological complications, which cause inflammation in the tissues surrounding the implant, and mechanical (prosthetic) complications, based on their causes. Once it is established that the implant has been correctly placed and all potential factors for early failure have been addressed, attention turns to biological complications, particularly peri-implant diseases. The questions below address scenarios in which the clinician suspects that biofilms on the implant surfaces are the primary etiological factors contributing to the development of peri-implant mucositis and peri-implantitis.

What is the definition of peri-implantitis?

Peri-implantitis is a destructive inflammatory process affecting functionally osseointegrated implants, characterized by bleeding in the soft tissues around the implant, increased periodontal pocket depth, and loss of alveolar bone [10]. According to the consensus report from the 2017 World Workshop for the Classification of Periodontal and Peri-Implant Diseases and Conditions, peri-implantitis is defined as "a pathological condition of dental plaque origin occurring in the tissues surrounding dental implants, characterized by inflammation of the mucosa surrounding the implant and subsequent progressive loss of supporting bone" [11].

What is the current prevalence of peri-implantitis?

Recent reports indicate that biological complications occurred in 52% of cases, while mechanical (prosthetic) complications were observed in 32% during the follow-up period [12]. Meta-analyses have estimated the weighted mean prevalence rates of peri-implant mucositis and peri-implantitis to be 43% (95% confidence interval [CI], 32%–54%) and 22% (95% CI, 14%–30%), respectively [13]. Renvert et al. [14] reported prevalences of peri-implantitis and peri-implant mucositis at 22.1% and 54.7%, respectively, in subjects 21–26 years post-implant placement, with an average follow-up duration of 23.3 years. A study conducted in Korea reported an overall implant survival rate of 95.87%, with peri-implant mucositis occurring in 39.7% of cases and peri-implantitis in 16.7% [15].

Does a prior history of periodontitis influence the incidence of peri-implantitis?

Research has shown that patients who have undergone periodontal treatment are at a statistically significantly higher risk of developing peri-implantitis and experiencing implant loss compared to those without a history of periodontal disease [16]. Meta-analyses of patient data indicate that individuals with periodontitis face a 2.29 times greater risk of peri-implantitis than those who are periodontally healthy [17].

In a study utilizing the recently revised classification system, no statistically significant correlation was observed between the stage or grade of periodontitis and the prevalence of peri-implantitis. However, it was reported that grade C periodontitis is associated with an increased risk of implant failure and more extensive marginal bone loss [18].

What other factors influence the prevalence of peri-implantitis?

Systemic conditions such as osteoporosis and diabetes, along with a patient's history of periodontitis, significantly increase the risk of peri-implantitis by impairing immune function and healing processes. Factors related to the implant also play a critical role in the prevalence of peri-implantitis. Differences in prosthesis type, specifically between cemented and screw-retained, as well as variations in implant diameter and mucosal height, can lead to increased plaque accumulation and inflammation of peri-implant tissues [19].

Moreover, surgical precision is crucial, as improper placement of an implant is associated with a higher risk of peri-implantitis. A study [8] has highlighted that surgical errors are more commonly linked to peri-implantitis (40.8%) than to prosthetic (30.4%) or purely plaque-induced (28.8%) factors.

Differences in diagnostic criteria, implant systems, and clinician expertise contribute further to discrepancies in reported prevalence rates. Standardizing these factors is essential for a comprehensive understanding and effective management of peri-implantitis.

SUMMARY STATEMENTS IN THE AREAS OF SYSTEMIC/LOCAL RISK INDICATORS AND ETIOLOGICAL FACTORS OF BIOLOGIC COMPLICATIONS

What are the major risk indicators for peri-implantitis?

Peri-implant diseases are caused by bacterial biofilms and are associated with specific risk indicators/factors [20]. The most significant risk indicators include poor oral hygiene, irregular maintenance, and a history of chronic periodontitis, including cases that remain untreated [11,21].

Research on peri-implantitis treatment indicates that anti-infective strategies are effective in reducing soft tissue inflammation and preventing the progression of peri-implant disease [11].

What are the systemic and behavioral risk indicators of peri-implantitis?

At the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions, it was noted that smoking and diabetes are potential risk indicators for peri-implant diseases [11]. Poorly controlled or uncontrolled type 2 diabetes increases the risk of complications by 2.75 times [22]. Chronic hyperglycemia disrupts implant-related bone regeneration by impairing angiogenesis [23]. Diabetes reduces bone formation markers such as osteocalcin, alkaline phosphatase, and procollagen type 1 N-terminal propeptide, and it promotes bone resorption by accumulating Advanced Glycation End Products, which trigger systemic inflammation [24]. Supportive maintenance programs have significantly reduced peri-implant complications in individuals with type 2 diabetes, bringing their outcomes closer to those of non-diabetic individuals over time [25].

Most of the literature presents scientific evidence supporting smoking as a risk factor for developing peri-implant disease [26]. Additionally, the risk of peri-implantitis increases with long-term use of non-steroidal anti-inflammatory drugs (3.2×), bisphosphonates (2.69×), and alcohol consumption exceeding 5 units per day (2.3×) [27]. Head and neck irradiation therapy decreases implant survival rates by 2.63 times, especially when implants are placed within 12 months of receiving radiation, regardless of the radiation dose [27]. According to the consensus report, implant treatment is contraindicated in cases of high-dose antiresorptive therapy due to complications; however, the risk of osteonecrosis remains low with low-dose drugs, as typically used in treating general osteoporosis [28].

Before considering implant surgery for these patients, it is necessary to conduct a thorough individual risk assessment. Additionally, patients with comorbidities must be closely monitored in collaboration with the supervising physician and undergo regular follow-up [29].

What additional risk factors for peri-implantitis have been identified?

There is limited evidence suggesting a link between peri-implantitis and factors such as submucosal excess cement residue [30] and implant positioning that impedes oral hygiene and maintenance. The roles of other potential risk indicators, including peri-implant keratinized mucosa, occlusal overload, titanium particles, bone compression necrosis, overheating, and micromotion, have yet to be fully determined [11]. Sarmiento et al. [31] revealed that most bone loss around implants is related to the accumulation of biofilm, followed by iatrogenic factors, exogenous stimuli, absence of keratinized gingiva, and exogenous pathology. This suggests that while bacterial plaque is the primary cause of inflammation, various issues during implant surgery or prosthetic procedures may also contribute to plaque accumulation, complicating the attribution of this issue solely to the patient's poor oral hygiene.

What is the impact of design elements of the implant supracrestal complex (ISC) on the risk of peri-implant mucositis and peri-implantitis?

The ISC is defined as the anatomical and functional region that includes the various components of the implant–abutment–prosthesis junction situated within the mucosal area [20]. Evidence suggests that modifying the prosthesis can enhance the effectiveness of peri-implant mucositis treatment when the original design of the prosthesis hinders access to oral hygiene [32].

The concept of platform switching, along with advancements in implant design, has led to the increasing belief that achieving zero bone loss is possible. The positioning of the prosthesis margin's microgap further from the alveolar crest level creates more favorable conditions for preventing inflammation [33].

Recent research results indicate that the prevalence of peri-implantitis is high when the emergence angle exceeds 30° and is combined with a convex emergence profile of the abutment/prosthesis [20], and when the implant prosthesis is splinted to both the mesial and distal adjacent implants [34].

What are the risks of positioning the crown margin below the mucosa level?

To optimize aesthetics, prostheses are often positioned below the mucosal margin. However, particularly in the posterior region, maintaining hygiene becomes challenging when the abutment-prosthesis interface is situated beneath the mucosal level. Moreover, there is a significantly higher risk of residual cement at subgingival abutment margins compared to supragingival and equigingival margins [35]. In the case of the cement-retained type, these cement residues can act as foreign bodies, causing inflammation and bone loss [36]. Limited evidence suggests that the risk of peri-implantitis increases when the distance between the crown restoration margin and the bone crest is less than 1.5 mm. Therefore, selecting the appropriate abutment is crucial to avoid placing submucosal crown margins too close to the alveolar bone crest, whether the prosthesis is screwed or cemented [36].

Does the soft-tissue phenotype surrounding the implant affect peri-implant diseases?

Recent recommendations have highlighted the importance of assessing changes in peri-implant soft tissue parameters, in addition to focusing on disease resolution following surgical treatment of peri-implantitis [20]. Research has emphasized that when gingival thickness is less than 3 mm, there is a risk of bone resorption to maintain a minimal soft tissue attachment around the implant [37]. Therefore, it is necessary to consider prosthetic interventions such as soft tissue grafting, using prostheses with smoothly polished surfaces, selecting abutments that are highly biocompatible with the gingiva, and employing removable screw-type prostheses.

The stability of the marginal mucosa relies not only on the characteristics of the peri-implant soft tissue but also on the condition of the underlying alveolar bone. If there is a bone dehiscence, it can cause mucosal recession, which subsequently heightens the risk of peri-implantitis, particularly when a rough area of the implant surface becomes exposed [36].

What are common problems associated with lack of keratinized mucosa (width)?

According to the current consensus, having enough high-quality keratinized gingiva is beneficial for controlling dental plaque. When keratinized gingiva is insufficient, soft tissue grafting is recommended to increase stability [38]. A meta-analysis has shown that inadequate keratinized gingiva around implants is linked to increased accumulation of dental plaque, as well as to gingival inflammation, recession, and attachment loss [39]. Numerous reviews have observed improvements in both the plaque index and the gingivitis index at sites where soft tissue grafting was performed to increase keratinized gingiva [40]. Although evidence regarding the long-term success rates of implants and their impact on complications remains limited, it is clinically clear that adequate keratinized gingiva around implants supports patient oral hygiene, improves aesthetic outcomes, and aids in accurate impression taking. Therefore, it is a critical factor to consider during the surgical planning phase.

DIAGNOSIS AND CLINICAL CHARACTERISTICS OF PERI‐IMPLANTITIS

Diagnosis of peri-implant diseases

Peri-implant diseases and related conditions encompass both plaque-induced and non-plaque-associated issues, including implant mucosal recession, mucosal hyperplasia, trauma-induced lesions, and other non-specific clinical conditions. The diagnosis of these peri-implant diseases, whether related to plaque or not, primarily depends on the detection of a plaque-induced active infection. This is indicated by symptoms such as bleeding on probing, exudate or suppuration, radiographic bone loss, and increased probing pocket depth [41].

How to define and diagnose peri-implant health, peri-implant mucositis and peri-implantitis

The following criteria are considered for defining the condition of peri-implant tissue [11,41].

Peri-implant health

• • Absence of bleeding and suppuration on gentle probing;

• • No increase in probing depth compared to previous examinations;

• • No bone loss beyond the changes in marginal bone levels associated with initial bone remodeling.

Peri-implant mucositis

• • Presence of bleeding and/or suppuration upon gentle probing, with or without an increase in probing depth relative to previous evaluations;

• • No bone loss beyond marginal bone level changes resulting from initial bone remodeling.

Peri-implantitis

• • Presence of bleeding and/or suppuration on gentle probing;

• • Increased probing depth compared to previous measurements;

• • Bone loss extending beyond the marginal bone level changes due to initial bone remodeling.

In cases where prior examination data are unavailable, the diagnosis of peri-implantitis could be made based on the following combination of factors

• • Bleeding and/or suppuration on gentle probing;

• • Probing depths of ≥6 mm;

• • Bone levels ≥3 mm apical of the most coronal portion of the intra-osseous part of the implant.

What are the tools for the diagnosis of peri-implant mucositis or peri-implantitis?

Early detection of inflammation is crucial for preventing peri-implant diseases. Marginal bone resorption around functioning implants is assessed using long-cone parallel radiographic projection techniques. Bleeding on probing serves as a key clinical indicator of soft tissue inflammation, helping to distinguish between peri-implant health, mucositis, and peri-implantitis. A periodontal probe is vital for monitoring the health of peri-implant tissues, with measurements influenced by factors such as inflammation, probing force, implant position, prosthetic contour, and the type of probe used. Plastic probes, which are more flexible, may record deeper depths compared to stainless steel probes, making it essential to maintain consistency in the type of probe used across examinations [41]. Furthermore, the established relationship between probing force and the frequency of bleeding on probing in healthy teeth indicates that excessive probing force can sometimes cause bleeding in surrounding tissues due to tissue trauma [29].

TREATMENT PROTOCOL FOR PERI-IMPLANT DISEASES

Since bacterial plaque is recognized as the primary etiological factor in peri-implant disease [42,43], current treatment approaches commonly align with those established for periodontitis [5].

Non-surgical treatment

Peri-implant mucositis is regarded as a precursor to peri-implantitis, similar to how gingivitis precedes periodontitis [21]. Non-surgical treatments are effective in managing peri-implant mucositis and serve as a preventive measure against peri-implantitis [44]. However, when the condition advances to peri-implantitis, non-surgical treatments typically become inadequate due to restricted visual and instrumental access, thus requiring surgical intervention [45,46].

To address this limitation, various solutions have been proposed. Removing the prosthesis has been shown to increase treatment efficacy by facilitating better access during non-surgical procedures [47]. Additionally, the combined use of systemic and local antibiotics with non-surgical debridement has been explored. Studies indicate that integrating non-surgical treatment with antibiotics, including metronidazole and minocycline, improves outcomes for peri-implantitis, though careful consideration of antibiotic resistance is necessary [48,49,50,51,52].

The design of implant restorations plays a critical role in the success of treatment. Over-contoured restorations that impede plaque control can increase the risk of peri-implantitis [34,53]. Conversely, adjusting the restoration to improve oral hygiene accessibility can significantly enhance the outcomes of non-surgical treatments [32]. It is crucial to ensure adequate embrasure space for self-cleansing, which involves maintaining a minimum horizontal distance of at least 1.5 mm from the implant to the adjacent teeth or at least 3 mm to an adjacent implant [54,55]. Additionally, the abutment should be designed with a concave shape to optimize the health and volume of the peri-abutment mucosa and to prevent unexpected bone resorption [34,53,56,57]. This is particularly critical for the middle implant in a multi-unit prosthesis that is splinted to both the mesial and distal adjacent implants [34]. It is also important to monitor for the loss of proximal contact, which can lead to food impaction, previously observed between the implant and the mesial tooth [58].

Surgical treatment

It is well known that a surgical approach was once considered inevitable for treating peri-implantitis lesions. Currently, there are several treatment modalities that clinicians can choose from based on the clinical situation [5,59]: access surgery, resective surgery, and regenerative surgery.

Access surgery

Access surgery, the most fundamental of surgical approaches, can be described as open flap debridement. This method is widely recognized as effective for the meticulous decontamination of the affected implant surface [60]. The main objective of this procedure is to thoroughly decontaminate the surface, which is essential for minimizing bacterial recolonization and enhancing re-osseointegration [61]. Traditional mechanical debridement tools, such as metal curettes and ultrasonic scalers, can damage the titanium surface of implants. Therefore, alternatives like titanium curettes, ultrasonic scalers with plastic tips, air powder abrasives, or rotating titanium brushes have been suggested and proven effective [62,63].

Despite the challenges posed by the surface topography of implant fixtures, which make it difficult to fully decontaminate affected areas, especially when access is restricted by prostheses or deep intrabony defects [5], chemical agents have been employed as adjuncts to enhance surface decontamination [64]. Previous research has shown that these agents, including citric acid, hydrogen peroxide, ethylene-diamine-tetraacetic acid, and chlorhexidine, are effective in reducing or eliminating bacteria and endotoxins on the implant surface, thereby improving treatment outcomes [65,66,67]. However, there is still no consensus on which chemical or pharmacological agent is the most effective [68].

Resective approach

When peri-implantitis results in a defect with a less contained or supracrestal configuration where regeneration is not indicated, resective surgery may be selected to facilitate better oral hygiene control during post-operative follow-up [5]. This approach involves a sequential procedure that includes: 1) contouring the bone to positively alter the peri-implant bone profile; 2) performing implantoplasty, which entails removing the supracrestally exposed implant threads and polishing the surface; and 3) apically repositioning the mucoperiosteal flap to reduce mucosal pocket depth [69]. Consequently, this may reduce the likelihood of biofilm accumulation and bacterial regrowth after the surgery, leading to a favorable long-term outcome [70].

In the meanwhile, there are some concerns regarding implantoplasty. First, while it increases surface smoothness, it may lead to biological complications due to titanium particles that are not completely removed [71]. Second, there is an increased risk of fixture fracture or tearing, especially in narrow-diameter implants with internal connections. This risk arises because thread removal results in a thinner wall surrounding the screw [72].

Regenerative approach

In regenerative surgery, peri-implant defects are addressed by filling them with bone graft materials after the affected fixture surface has been decontaminated. The predictability of treatment outcomes is highly dependent on the configuration of the defect. Research has shown that circumferential, 2- or 3-wall intrabony defects exhibit higher regenerative potential [73]. While grafting bone substitutes into the defect results in radiographic defect fill, reduced probing pocket depth, and minimized postoperative mucosal recession, it does not significantly differ from resective or access flap surgery in terms of resolving inflammation [74]. Additionally, some studies have suggested that outcomes may be improved when bone grafting is combined with growth factors such as enamel matrix derivative or platelet-derived growth factor [73].

In cases where defects include both suprabony and intrabony compartments, a combination of resective and regenerative procedures may be suitable [74]. This approach entails performing resective surgery on the suprabony component and regenerative surgery on the intrabony component, effectively accomplishing both inflammation relief and bone regeneration simultaneously.

Adjunctive soft tissue grafting

Regardless of the type of surgical treatment, it is advisable to include soft tissue grafting (using either autogenous tissue or a collagen substitute) as needed. This is because peri-implant soft tissue of adequate quality and thickness is considered crucial for maintaining peri-implant health and reducing the risk of peri-implantitis recurrence [43]. When there is less than 2 mm of keratinized mucosa and a shallow vestibule, patients are likely to experience discomfort and difficulties with self-plaque removal [75]. Moreover, thin mucosa may limit the mucosal seal, potentially leading to adverse effects on marginal bone stability [76].

Fixture removal

Once an implant is deemed to have failed, the clinician's only option may be to remove the compromised fixture [77]. Although there is controversy surrounding the definitive criteria for removing an implant diagnosed with peri-implantitis, it is generally recommended to remove the implant if 1) the implant is mobile due to complete loss of osseointegration [78], 2) there is a fracture or tearing of the fixture [79,80], or 3) peri-implant bone loss exceeds half of the total implant length [81]. While the extent of vertical bone loss may be debatable, the failure rate of peri-implantitis treatment is approximately 20 times higher when less than 50% of the bone remains in contact with the implant [82].

Maintenance care after the peri-implantitis treatment

Similar to the management of periodontitis, regular maintenance is crucial for peri-implantitis. To optimize this maintenance, it is essential to evaluate the risk of peri-implantitis. The Implant Disease Risk Assessment (IDRA) tool has been developed to assess patient-level risks by examining eight key risk factors, including history of periodontitis, prevalence of probing depths, and factors related to the implant prosthesis [83]. This tool categorizes patients into low, moderate, or high-risk groups, which aids in designing personalized maintenance programs and enhances communication and motivation with patients. Based on individual risk levels, regular maintenance visits are recommended every 3–6 months, as intervals longer than 6 months have been shown to reduce the effectiveness of maintenance.

Periodic supportive therapy, including the removal of supra- and submucosal biofilm at least once every 6 months, effectively maintains the clinical success of treatments. Research has shown that maintenance, including plaque control and adjunctive local antibiotic applications every 3–6 months, reduces the prevalence of peri-implantitis [84,85]. However, the optimal frequency for maintenance recalls to ensure peri-implant tissue health remains unclear. A recent systematic review and meta-analysis revealed that a 6-month interval yielded better outcomes compared to a 3-month interval [84], a finding that warrants further investigation to determine the underlying reasons. It is widely recognized that patient compliance plays a crucial role in the health of peri-implant tissues. Studies have indicated that non-compliance or reduced compliance significantly increases the prevalence of peri-implant diseases [86]. A previous cross-sectional study reported that patients with erratic compliance (fewer than 2 visits per year) had a higher likelihood of experiencing peri-implant disease compared to those with regular compliance (2 or more visits per year) [85]. Furthermore, a recent prospective study showed that individuals adhering to a regular maintenance schedule with intervals not exceeding 9 months maintained better peri-implant tissue health than those with irregular schedules and intervals of up to 18 months [87]. This underscores clinicians’ critical role in ensuring patients adhere to maintenance protocols. Achieving this may require thorough motivational interventions and reinforcement [88]. Additionally, for patients covered by public insurance or assistance, such as Korean citizens, leveraging national policies could also be an effective strategy to increase compliance.

CLINICAL RECOMMENDATIONS

Based on the current understanding of peri-implant diseases, the following clinical recommendations are proposed (Figure 1).

Figure 1. Clinical recommendations for peri-implant diseases.

IDRA: implant disease risk assessment.

In cases of peri-implant mucositis

Similar to gingivitis, peri-implant mucositis can be successfully managed with non-surgical treatment [44]. Given that dental plaque is the primary etiologic factor of peri-implantitis [89], it is important for both clinicians and patients to maintain rigorous oral hygiene.

Beforehand, it is crucial for clinicians to establish an appropriate environment around the implant to optimize peri-implant tissue health. First, a sufficient amount and good quality of both soft and hard tissue should surround the fixture, particularly at the crestal level [43]. Second, the depth at which the implant is placed should ensure an adequate supracrestal mucosal thickness, which serves as a biological barrier [90,91]. Third, the design of the prosthesis is critical; it is advisable to avoid over-contoured prostheses [34,53]. If necessary, the prosthesis compartments should be adjusted to facilitate self-cleansing at the embrasure, especially when the middle implant is splinted with both mesial and distal adjacent fixtures [34]. Finally, the clinician must meticulously remove any excess luting cement after placing the cement-retained prosthesis [92].

In cases of peri-implantitis

For implants diagnosed with peri-implantitis that are not severe enough to require removal, comprehensive treatment typically starts with non-surgical methods, such as mechanical and chemical debridement [44]. In most cases, removing the prosthesis prior to treatment is beneficial to improve accessibility. The use of systemic or local antibiotics is strongly recommended. A re-evaluation is usually conducted 3 months after the non-surgical treatment to determine subsequent steps [5].

If non-surgical treatment fails to sufficiently improve peri-implant conditions, surgical intervention is recommended [5,59]. CBCT analysis is crucial for confirming defect configurations, which assists in determining whether to opt for resective, access, reconstructive surgery, or a combination of these approaches [74]. After successful treatment, patients should be enrolled in a maintenance program. The frequency of recall visits should be determined by risk assessments using the IDRA tool [83]. Each visit should include professional plaque control and reinforcement of oral hygiene practices, along with continuous re-evaluation to ensure the stability of peri-implant conditions. If conditions deteriorate, the treatment cycle must be restarted, underscoring the chronic nature of peri-implantitis and the necessity for ongoing management [21].

For failed implants

Clinicians should consider removing a failed implant characterized by loss of osseointegration or fixture fracture/tearing [77]. Additionally, it is advisable to remove fixtures that exhibit severe peri-implant bone loss exceeding 50% of the fixture length, due to the poor predictability of treatment outcomes [81]. This approach may be particularly favored in South Korea, where patients are generally more willing to opt for re-implantation due to its cost-effectiveness [93].

Removal of the affected implant completely alleviates the inflammation, but it also presents clinicians with the challenge of reconstructing the soft and hard tissues damaged by pre-existing peri-implantitis to restore function and aesthetics. Prior to this reconstruction, it is essential to thoroughly address all factors that contributed to the previous implant failure, ensuring that the newly installed implant does not encounter the same issues [94].

CONCLUSIONS

It is critical for clinicians to manage peri-implant diseases comprehensively, which includes conducting an in-depth risk assessment, developing individualized treatment plans, and establishing thorough maintenance protocols. Additionally, regular follow-ups and patient education are crucial to prevent disease recurrence and ensure the long-term health of peri-implant tissues.