Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental implants

Heterogeneity of outcomes in randomized controlled trials on implant prosthodontic therapy is hindering comparative effectiveness research: meta-research study

BACKGROUND

Consistency in outcomes across clinical trials allows for comparing and combining results from different studies. A core outcome set (COS), representing a minimally agreed standardized group of outcomes that should be monitored and measured through research in a specific field of medicine, is not yet available for trials in implant prosthodontic (dental implant) therapy. This meta-research study aimed to analyze outcomes used in clinical trials on implant prosthodontic therapy.

METHODS

We searched the Cochrane Oral Health Group (COHG) register to identify systematic reviews of interventions in implant prosthodontic therapy published by October 2023. From the randomized controlled trials (RCTs) included in the relevant reviews, we extracted data on the characteristics of the included trials and the outcomes used. We categorized outcomes into domains.

RESULTS

From 182 systematic reviews in the COHG register, we included 11 systematic reviews on dental implant therapy. The reviews included 117 unique RCTs with 4725 participants, published from 1995 to 2020, which analyzed 74 different outcomes. Using different definitions, implant failure was analyzed in 73 RCTs. Seventeen RCTs did not define implant failure. Failure was most often (30 RCTs) followed up for one year. Only one RCT assessed implant failure after five years. Trials used 17 definitions of implant failure, while 17 trials did not report on the criteria of implant failure. Complications were analyzed in 48 RCTs, although they were not clearly defined in 12 RCTs. Failure of prosthodontic supra-structure was analyzed in 74 RCTs, with definitions of failure and criteria not clearly defined in 44 RCTs. Trials considered adverse events, peri-implant tissue health, patient attitudes, and other outcomes, including cost, aesthetics, or procedure duration. These outcomes were often different between trials. Twenty-six outcomes were used only once per study.

CONCLUSIONS

Clinical trials in implant prosthodontics used different outcomes, different definitions of outcomes and used different times to monitor them. Standardization of outcomes is necessary to allow comparability and evidence synthesis about the effectiveness of implant prosthodontic therapy.

Influence of eight debridement techniques on three different titanium surfaces: A laboratory study

OBJECTIVES

Debridement methods may damage implant surfaces. This in vitro study investigated eight debridement protocols across three implant surfaces to assess both biofilm removal and surface alterations.

MATERIAL AND METHODS

One hundred sixty commercially pure titanium discs were treated to simulate commercially available titanium implant surfaces-smooth, abraded and abraded and etched. Following inoculation with whole human saliva to create a mixed species biofilm, the surfaces were treated with eight debridement methods currently used for clinical peri-implantitis (n = 10). This included air abrasion using powders of glycine, sodium bicarbonate and calcium carbonate; conventional mechanical methods-piezoelectric scaler, carbon and stainless steel scalers; and a chemical protocol using 40% citric acid. Following treatment, remaining biofilm was analysed using scanning electron microscopy and crystal violet assays. For statistical analysis, ANOVA was applied (p < 0.05).

RESULTS

All debridement techniques resulted in greater than 80% reduction in biofilm compared with baseline, irrespective of the surface type. Glycine powder delivered through an air polishing system eliminated the most biofilm. Mechanical instruments were the least effective at eliminating biofilm across all surfaces and caused the greatest surface alterations. Citric acid was comparable with mechanical debridement instruments in terms of biofilm removal efficacy. Titanium surfaces were least affected by air abrasion protocols and most affected by mechanical methods.

CONCLUSIONS

Mechanical protocols for non-surgical debridement should be approached with caution. Glycine powder in an air polisher and 40% citric acid application both gave minimal alterations across all implant surfaces, with glycine the superior method in terms of biofilm removal.

Impact of Smoking Habit on Peri-Implant Indicators following Different Therapies: A Systematic Review

Peri-implant disease and its treatment is becoming a major concern for clinicians as the number of implants placed each year is rising. Smoking is a common habit, and it is associated with an increased risk of developing peri-implant disease. The role of smoking in the response to peri-implant treatment has never been investigated. Searches were conducted in electronic databases to screen articles published until August 2021. The included studies had at least two groups of patients: peri-implant disease only or peri-implant disease and smoking status. Outcomes of interest included plaque index (PI), probing depth (PD), bleeding on probing (BoP), radiographic crestal bone loss (CBL), and analysis of peri-implant sulcular fluid. Seven hundred and forty-nine articles were found in the databases, only 71 articles potentially qualified. A total of seven studies with a minimum follow-up of six months were included. There is no homogeneity in the diagnosis, smoker definition and treatment proposed. All surgical and non-surgical treatment have statistically significantly different outcomes in smokers and nonsmokers. Recognizing this study’s limitations, we conclude that smoking might play a significant role on the outcome of peri-implant disease treatment. None of the proposed treatments appear to be significantly more effective.

Assessment of the Soft-Tissue Seal at the Interface between the Base of the Fixed Denture Pontic and the Oral Mucosa

Fixed dentures (bridges) are often selected as a treatment option for a defective prosthesis. In this study, we assess the contact condition between the base of the pontic and oral mucosa, and examine the effect of prosthetic preparation and material biocompatibility. The molars were removed and replaced with experimental implants with a free-end type bridge superstructure after one week. In Experiment 1, we assessed different types of prosthetic pre-treatment: (1) the untreated control group (Con: mucosa recovering from the tooth extraction); (2) the laser irradiation group (Las: mucosa recovering after the damage caused by a CO₂ laser); and (3) the tooth extraction group (Ext: mucosa recovering immediately after the teeth extraction). In Experiment 2, five materials (titanium, zirconia, porcelain, gold-platinum alloy, and self-curing resin) were placed at the base of the bridge pontic. Four weeks after the placement of the bridge, the mucosa adjacent to the pontic base was histologically analyzed. In Experiment 1, the Con and Las groups exhibited no formation of an epithelial sealing structure on the pontic base. In the Ext group, adherent epithelium was observed. In Experiment 2, the sealing properties at the pontic interface were superior for titanium and the zirconia compared with those made of porcelain or gold-platinum alloy. In the resin group, a clear delay in epithelial healing was observed.

Effectiveness of Brushing Associated With Oral Irrigation in Maintenance of Peri-Implant Tissues and Overdentures: Clinical Parameters and Patient Satisfaction

Hygiene of implant-supported prostheses and the health of peri-implant tissues are considered to be predictive factors of successful prosthetic rehabilitation. Therefore, the purpose of this study was to evaluate the effectiveness of brushing associated with oral irrigation measured as biofilm-removing capacity, maintenance of healthy oral tissues, and patient satisfaction. A randomized, crossover clinical trial was conducted with 38 patients who wore conventional maxillary complete dentures and mandibular overdentures retained by the O-ring system. The patients were instructed to use the following hygiene methods for 14 days: mechanical brushing (MB; brush and dentifrice, control) and MB with oral irrigation (Waterpik [WP], experimental). Biofilm-removing capacity and maintenance of healthy oral tissues were evaluated by the modified plaque index (PI), gingival index (GI), probing depth (PD), and bleeding on probing index (BP) recorded at baseline and after each method. In parallel, patients answered a specific questionnaire using a visual analog scale after each hygiene method. Data were analyzed by Friedman and Wilcoxon tests (α = .05). The results showed significantly lower PI, GI, PD, and BP after application of the hygiene methods (P < .001) than those observed at baseline. However, no significant difference was found between MB and WP. The responses to the satisfaction questionnaire for both methods showed high mean values for all questions, with no statistically significant difference found between the answers given after the use of MB and WP (P > .05). The findings suggest that WP was effective in reducing PI, GI, PD, and BP indices and provided a high level of patient satisfaction.

Management of Peri-Implant Diseases: A Survey of Australian Periodontists

BACKGROUND/AIM

This survey-based study aims to explore the clinical management protocols of followed by Australian periodontists in relation to peri-implant diseases.

MATERIALS AND METHODS

A five-part online questionnaire was developed and administered through email. Descriptive statistics were used for analysis, with the univariate associations between a categorical outcome and the variables evaluated using Pearson's Chi-squared test.

RESULTS

The survey yielded 99 responses, resulting in a response rate of 41.8%. Most participants were male and aged 35-44 years. More than a quarter of practitioners had been placing implants for 6-10 years and almost two-fifths of practitioners placed 1-10 implants per month. The estimated prevalence of peri-implant mucositis and peri-implantitis in the general Australian population was 47% and 21%, respectively. Practitioners reported using systemic antibiotics to manage peri-implant mucositis (7%) and (72%) peri-implantitis lesions, with a combination of amoxicillin and metronidazole. Most common treatment modalities were oral hygiene instructions, nonsurgical debridement and antimicrobial gel/rinse. Surgical debridement and systemic antibiotics were also often used for peri-implantitis treatment. Practitioners preferred a 3-month clinical follow-up and 6-month radiographic evaluation. Furthermore, three-quarters of practitioners rated their management as moderately effective, although upwards of nine-tenths expressed the need for further training and awareness.

CONCLUSION

This study confirms a significant use of empirical treatment modalities due to lack of standard therapeutic protocol. However, some approaches followed by the specialists may provide a basis to formulate a therapeutic protocol for peri-implant disease management.

Role of Dental Implant Homecare in Mucositis and Peri-implantitis Prevention: A Literature Overview

Background:

Correlation between high plaque index and inflammatory lesions around dental implants has been shown and this highlights the importance of patient plaque control. Until now, knowledge of peri-implant home care practices has been based on periodontal devices.

Objective:

The aim of this overview is to identify the presence of scientific evidence that peri-implant homecare plays a role in mucositis and peri-implantitis prevention.

Methods:

Different databases were used in order to detect publications reflecting the inclusion criteria. The search looked into peri-implant homecare studies published from 1991 to 2019 and the terms used for the identification of keywords were: Dental implants, Brush, Interproximal brushing, Interdental brushing, Power toothbrush, Cleaning, Interdental cleaning, Interspace cleaning, Flossing, Super floss, Mouth rinses, Chlorhexidine. The type of studies included in the selection for this structured review were Randomized Clinical Trials, Controlled Clinical Trials, Systematic Reviews, Reviews, Cohort Studies and Clinical cases.

Results:

Seven studies fulfilled all the inclusion criteria: 3 RCTs, one Consensus report, one cohort study, one systematic review and one review. Other 14 studies that partially met the inclusion criteria were analyzed and classified into 3 different levels of evidence: good evidence for RCTs, fair evidence for case control and cohort studies and poor evidence for expert opinion and case report.

Conclusion:

Not much research has been done regarding homecare implant maintenance. Scientific literature seems to show little evidence regarding these practices therefore most of the current knowledge comes from the periodontal literature. Manual and powered toothbrushes, dental floss and interdental brushes seem to be useful in maintaining peri-implant health. The use of antiseptic rinses or gels does not seem to have any beneficial effects.

It can be concluded that to better understand which are the most effective home care practices to prevent mucositis and peri-implantitis in implant-rehabilitated patients, new specific high evidence studies are needed.

An Antimicrobial Dental Light Curable Bioadhesive Hydrogel for Treatment of Peri-Implant Diseases

Dental implants constitute the standard of care to replace the missing teeth, which has led to an increase in the number of patients affected by peri-implant diseases (PIDs). Here, we report the development of an antimicrobial bioadhesive, GelAMP, for the treatment of PIDs. The hydrogel is based on a visible light-activated naturally-derived polymer (gelatin) and an antimicrobial peptide (AMP). The optimized formulation of GelAMP could be rapidly crosslinked using commercial dental curing systems. When compared to commercial adhesives, the bioadhesives exhibited significantly higher adhesive strength to physiological tissues and titanium. Moreover, the bioadhesive showed high cytocompatibility and could efficiently promote cell proliferation and migration in vitro. GelAMP also showed remarkable antimicrobial activity against Porphyromonas gingivalis. Furthermore, it could support the growth of autologous bone after sealing calvarial bone defects in mice. Overall, GelAMP could be used as a platform for the development of more effective therapeutics against PIDs.

Repeatedly Applied Peptide Film Kills Bacteria on Dental Implants

The rising use of titanium dental implants has increased the prevalence of peri-implant disease that shortens their useful life. A growing view of peri-implant disease suggests that plaque accumulation and microbiome dysbiogenesis trigger a host immune inflammatory response that destroys soft and hard tissues supporting the implant. The incidence of peri-implant disease is difficult to estimate, but with over 3 million implants placed in the USA alone, and the market growing by 500,000 implants/year, such extensive use demands additional interceptive approaches. We report a water-based, nonsur-gical approach to address peri-implant disease using a bifunctional peptide film, which can be applied during initial implant placement and later reapplied to existing implants to reduce bacterial growth. Bifunctional peptides are based upon a titanium binding peptide (TiBP) optimally linked by a spacer peptide to an antimicrobial peptide (AMP). We show herein that dental implant surfaces covered with a bifunctional peptide film kill bacteria. Further, using a simple protocol for cleaning implant surfaces fouled by bacteria, the surface can be effectively recoated with TiBP-AMP to regain an antimicrobial state. Fouling, cleansing, and rebinding was confirmed for up to four cycles with minimal loss of binding efficacy. After fouling, rebinding with a water-based peptide film extends control over the oral microbiome composition, providing a novel nonsurgical treatment for dental implants.

Biofilm Removal and Bacterial Re-Colonization Inhibition of a Novel Erythritol/Chlorhexidine Air-Polishing Powder on Titanium Disks

Air-polishing with low abrasiveness powders is fast arising as a valid and mini-invasive instrument for the management of biofilm colonizing dental implants. In general, the reported advantage is the efficient removal of plaque with respect to the titanium integrity. In the present study, we evaluated the in situ plaque removal and the preventive efficacy in forestalling further infection of an innovative erythritol/chlorhexidine air-polishing powder and compared it with sodium bicarbonate. Accordingly, two peri-implantitis-linked biofilm formers, strains Staphylococcus aureus and Aggregatibacter actinomycetemcomitans, were selected and used to infect titanium disks before and after the air-polishing treatment to test its ability in biofilm removal and re-colonization inhibition, respectively. Biofilm cell numbers and viability were assayed by colony-forming unit (CFU) count and metabolic-colorimetric (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide) (XTT) assay. Results demonstrated that air-polishing performed with either sodium bicarbonate or erythritol/chlorhexidine was effective in reducing bacteria biofilm viability and number on pre-infected specimens, thus showing a similar ability in counteracting existing infection in situ; on the other hand, when air-polished pre-treated disks were infected, only erythritol/chlorhexidine powder showed higher post-treatment biofilm re-growth inhibition. Finally, surface analysis via mechanical profilometry failed to show an increase in titanium roughness, regardless of the powder selected, thus excluding any possible surface damage due to the use of either sodium bicarbonate or erythritol/chlorhexidine.

Implant maintenance treatment and peri-implant health

Data sourcesMedline (PubMed), Embase, Cochrane Central Register of Controlled Trials and Cochrane Oral Health Group Trials Register databases and a manual search of the Journal of Dental Research, Journal of Clinical Periodontology, Journal of Periodontology and the International Journal of Periodontics and Restorative Dentistry from January 2014 to February 2015.Study selectionProspective, retrospective, randomised or not, case-controlled or case series trials showing the incidence or recurrence of peri-implant disease plus or minus PIMT over more than six months.Data extraction and synthesisThree reviewers independently selected studies and abstracted data with two reviewers assessing study quality using the Newcastle-Ottawa Scale (NOS). A multivariate binomial regression was used to examine the data.ResultsThirteen studies were included with ten contributing to the meta-analysis. The average quality assessment score (NOS) was 5.3 out of a possible nine, only one paper achieved eight. At patient level mucositis ranged from 18.5-74.2% and peri-implantitis from 8-28%, with significant effects being seen for treatment (z= -14.36, p<0.001). Mucositis was affected by history of periodontitis and mean PIMT at implant and patient levels, respectively. For peri-implantitis there were also significant effects of treatment (z = -16.63, p<0.001). Increased peri-implantitis was observed for patients with a history of periodontal disease. (z=3.76, p<0.001). Implants under PIMT have 0.958 the incident event compared to those with no PIMT.ConclusionsWithin the limitations of the present systematic review it can be concluded that implant therapy must not be limited to placement and restoration of dental implants, but to the implementation of PIMT to potentially prevent biological complications and heighten the long-term success rate. Although it must be tailored to a patients risk profiling, our findings suggest reason to claim a minimum recall PIMT interval of five to six months. Additionally, it must be stressed that even in the establishment of PIMT, biological complications might occur. Hence, patient-, clinical-, and implant-related factors must be thoroughly explored.

Bone Response and Soft Tissue Changes Around Implants With/Without Abutments Supporting Fixed Partial Dentures: Results From a 3-Year, Prospective, Randomized, Controlled Study

BACKGROUND

Diverging opinions exist regarding rough surface abutment usage, and abutment exclusion effects are unstudied.

PURPOSE

The study aims to: (1) assess tissue response to oxidized or machined abutments or no abutment; and (2) evaluate immediate implant-loading effects.

MATERIALS AND METHODS

In a 2005-2008 parallel-group randomized, clinical trial, 50 partially edentulous subjects received three Brånemark TiUnite™ (Nobel Biocare®, Gothenburg, Sweden) implants. Superstructures were attached via abutments (one with a TiUnite surface - AOX, and one with a machine-milled surface - AM) or directly at implant level (IL). Implants were immediately loaded (test) or unloaded for 3 months (control). Postoperative examinations were done up to 3 years.

RESULTS

Forty-seven subjects were reexamined after 3 years. Four and two implants were lost in test and control groups, respectively, during the first year. Thereafter, no implant loss occurred (95.7% survival). After 1 year, mean (SEM) peri-implant marginal bone loss (MBL) was 1.33 (0.08) mm (test) and 1.25 (0.08) mm (control). Between 1 and 3 years, a nonsignificant MBL occurred: 0.36 (0.08) mm (test) and 0.33 (0.06) mm (control). Similar MBL was found at IL (1.81 [0.93] mm) and AOX (1.77 [0.14] mm) after 3 years and was significantly lower at AM (1.42 [0.17] mm) than at IL (groups merged); 42% of the implants displayed mucosal bleeding at 3 years and probing pocket depths varied between 2.13 (0.12) mm and 3.62 (0.15) mm, significantly lower buccally. Bleeding on probing (BoP) in minute amounts was found in 30-45% of the sites and abundant BoP at about 20% of the sites. Soft tissue retracted mostly during year 1 and was more pronounced buccally. Regression analyses revealed significant effects from smoking, periodontal disease, abundant BoP, and a low initial implant stability quotient on MBL.

CONCLUSIONS

No further significant MBL was found between 1 and 3 years, irrespective of loading protocol. Use of machined abutments may benefit marginal bone stability over time.

Peri-implant versus periodontal wound healing

AIM

Peri-implant gingival healing following one-stage implant placement was investigated and compared to periodontal healing.

METHODS

Healing at surgical sites [implant (I) and adjacent teeth (T+)] was compared to non-operated tooth (T-) in non-smokers receiving one-stage implant. Periodontal Indices (PI, GI) were recorded at surgery and up to 12 weeks post-operatively. Peri-implant (PICF) and gingival crevicular fluids (GCF) were analysed for cytokines, collagenases and inhibitors. Data were analysed by linear mixed model regression analysis and repeated measures anova.

RESULTS

Forty patients (22 females; 21-74 years old) completed the study. Surgical site GI, increased at week 1, decreased significantly during early healing (weeks 1-3; p = 0.0003) and continually decreased during late healing (weeks 6-12) for I (p < 0.01). PICF volume decreased threefold by week 12 (p = 0.0003). IL-6, IL-8, MIP-1β and TIMP-1 levels significantly increased at surgical sites at week one, significantly decreasing thereafter (p < 0.016). Week one IL-6, IL-8 and MIP-1β levels were ~threefold higher and TIMP-1 levels 63% higher, at I compared to T+ (p = 0.001).

CONCLUSION

Peri-implant gingival healing, as determined by crevicular fluid molecular composition, differs from periodontal healing. The observed differences suggest that peri-implant tissues, compared to periodontal tissues, represent a higher pro-inflammatory state.

Systematic review of quality of reporting, outcome measurements and methods to study efficacy of preventive and therapeutic approaches to peri-implant diseases

AIM

To systematically review the literature and to assess the quality of reporting, outcome measurements and methods in both preventive and therapeutic approaches to peri-implant mucositis (PM) and peri-implantitis (PI).

MATERIALS AND METHODS

Randomized (RCT) and Controlled Clinical Trials (CCT), evaluating preventive or therapeutic interventions in patients with PM or PI, were identified through searching in electronic databases and in relevant journals. Reporting and methods were evaluated through an analysis of the risk of biases and quality score. Sub-analysis was performed in four subgroups: prevention of PM and PI, treatment of PM, and non-surgical and surgical treatment of PI.

RESULTS

Thirty-two trials (29 RCT) were identified as accomplishing inclusion criteria after full-text reading. Seven focused on prevention, and among those dealing with therapy, six were related to PM and 19 related to PI therapy (10 non-surgical and 9 surgical). Analysis found that quality of reporting and methods was generally low and surrogate outcomes were often chosen.

CONCLUSIONS

Current literature on PM and PI prevention and treatment does not allow extracting applicable clinical information. Quality of methods and reporting guidelines should be encouraged. In particular, ad hoc guidelines should be designed for peri-implant diseases.

Effectiveness and safety of a mouthwash containing essential oil ingredients

The mouthwash, Listerine®, was compounded in 1879 from four essential oils. Later, the oils were replaced by one ingredient per oil with approximately 25% ethanol as a vehicle to keep them in solution. From then on, Listerine® was no longer a medicinal plant product. In 2003, a review by the FDA Subcommittee on Oral Health Care Drug Products for Over-the-Counter Human Use concluded that the product is effective and safe, and a review of studies published in the meantime showed that Listerine® fulfils the consensus criteria for an effective antigingivitis/antiplaque product. However, concerns have been raised about the long-term safety of some of the ingredients, particularly the ethanol content, and in the light of these concerns, the evidence has been re-examined for both the efficacy and safety of Listerine®. In summary, the studies support the claim that Listerine® shows benefit for oral health, but the concerns over its safety remain to be clarified. Until these have been addressed, high risk populations (children, alcohol addicts, patients with genetic deficiencies in ethanol metabolism) should use alcohol-free mouthwashes for the maintenance of oral health.

Interventions for replacing missing teeth: treatment of peri-implantitis

BACKGROUND

One of the key factors for the long-term success of oral implants is the maintenance of healthy tissues around them. Bacterial plaque accumulation induces inflammatory changes in the soft tissues surrounding oral implants and it may lead to their progressive destruction (peri-implantitis) and ultimately to implant failure. Different treatment strategies for peri-implantitis have been suggested, however it is unclear which are the most effective.

OBJECTIVES

To identify the most effective interventions for treating peri-implantitis around osseointegrated dental implants.

SEARCH METHODS

We searched the Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE. Handsearching included several dental journals. We checked the bibliographies of the identified randomised controlled trials (RCTs) and relevant review articles for studies outside the handsearched journals. We wrote to authors of all identified RCTs, to more than 55 dental implant manufacturers and an Internet discussion group to find unpublished or ongoing RCTs. No language restrictions were applied. The last electronic search was conducted on 9 June 2011.

SELECTION CRITERIA

All RCTs comparing agents or interventions for treating peri-implantitis around dental implants.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two review authors. We contacted the authors for missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals (CI). Heterogeneity was to be investigated including both clinical and methodological factors.

MAIN RESULTS

Fifteen eligible trials were identified, but six were excluded. The following interventions were compared in the nine included studies: different non-surgical interventions (five trials); adjunctive treatments to non-surgical interventions (one trial); different surgical interventions (two trials); adjunctive treatments to surgical interventions (one trial). Follow-up ranged from 3 months to 4 years. No study was judged to be at low risk of bias.Statistically significant differences were observed in two small single trials judged to be at unclear or high risk of bias. After 4 months, adjunctive local antibiotics to manual debridement in patients who lost at least 50% of the bone around implants showed improved mean probing attachment levels (PAL) of 0.61 mm (95% confidence interval (CI) 0.40 to 0.82) and reduced probing pockets depths (PPD) of 0.59 mm (95% CI 0.39 to 0.79). After 4 years, patients with peri-implant infrabony defects > 3 mm treated with Bio-Oss and resorbable barriers gained 1.4 mm more PAL (95% CI 0.24 to 2.56) and 1.4 mm PPD (95% CI 0.81 to 1.99) than patients treated with a nanocrystalline hydroxyapatite.

AUTHORS' CONCLUSIONS

There is no reliable evidence suggesting which could be the most effective interventions for treating peri-implantitis. This is not to say that currently used interventions are not effective.A single small trial at unclear risk of bias showed the use of local antibiotics in addition to manual subgingival debridement was associated with a 0.6 mm additional improvement for PAL and PPD over a 4-month period in patients affected by severe forms of peri-implantitis. Another small single trial at high risk of bias showed that after 4 years, improved PAL and PPD of about 1.4 mm were obtained when using Bio-Oss with resorbable barriers compared to a nanocrystalline hydroxyapatite in peri-implant infrabony defects. There is no evidence from four trials that the more complex and expensive therapies were more beneficial than the control therapies which basically consisted of simple subgingival mechanical debridement. Follow-up longer than 1 year suggested recurrence of peri-implantitis in up to 100% of the treated cases for some of the tested interventions. As this can be a chronic disease, re-treatment may be necessary. Larger well-designed RCTs with follow-up longer than 1 year are needed.