Peri-implantitis Patients Research Articles

The effects of Lactobacillus reuteri probiotics combined with azithromycin on peri-implantitis: A randomized placebo-controlled study

PurposeThe aim of this randomized placebo-controlled clinical study was to investigate the effects of a probiotic tablet containing Lactobacillus reuteri in peri-implantitis patients. MethodsSubjects comprised 30 patients with mild to moderate peri-implantitis. A baseline clinical examination and microbiological assessment were conducted, followed by an antibiotics treatment (azithromycin, 500mg, once a day for 3 days). Subjects were divided into probiotic and placebo groups. The clinical examination and bacterial sampling were performed 0, 4, 12 and 24 weeks after the intake of probiotics. The clinical examination included probing pocket depth (PPD), bleeding on probing (BOP), the modified plaque index (mPI), and modified bleeding index (mBI). The number of bacteria was assessed using the PCR-invader method. The Wilcoxon rank-sum test and Wilcoxon signed-rank test with Bonferroni corrections were used for data analyses. ResultsAlthough the number of bacteria decreased after the administration of azithromycin in both groups, they increased again thereafter. No significant difference was observed in bacterial numbers between the two groups. Although PPD in the probiotics group was significantly lower at 4 and 24 weeks than at 0 weeks (p<0.05), a significant decrease did not occur in the placebo group. The mBI score at 24 weeks was significantly lower in the probiotics group than in the placebo group (p<0.05). No significant difference was observed in BOP or mPI between the two groups. ConclusionThese results suggested that probiotics prevent inflammation by affecting host responses rather than improving microbial flora in peri-implant sulci in peri-implantitis patients.

The association between three attitude-related indexes of oral hygiene and secondary implant failures: A retrospective longitudinal study.

This study evaluated the strength of the association between three widely used clinical indexes considered as distal behavioural indicators of attitude-related oral status (an index of oral hygiene, the plaque index [PI] and two periodontal indexes, that is the presence of bleeding on probing [BOP] and of pockets probing depth [PPD]) and secondary implant failure due to peri-implantitis in patients rehabilitated with cemented prosthesis. The study included patients who underwent implant-prosthetic rehabilitation and had joined the programme of maintenance of the same hospital. Implant failures, number of months between implant insertion and implant loading, and patients' surgical protocol were monitored and recorded. Further, PI, BOP and PPD-all attitude-related indicators of oral hygiene and periodontal inflammation-were recorded and related, in terms of odds ratios (ORs ) and corresponding risk factors, to secondary implant failures. A total of 1427 patients (2673 implants) were enrolled. The follow-up ranged from 1.5 to 9years (mean 5.3years±1.3). The cumulative survival rate was 98.01%. Thirty-two patients (36 implants, 1.36% of all implants) had implant failure. A statistically significant association between PI, BOP, PPD and secondary failures due to peri-implantitis was observed. Within the limitations of this study, all three attitude-related behavioural indicators-the plaque index (PI), bleeding on probing (BOP) and abnormal probing pocket depth (PPD)-proved to be significant risk indicators for secondary implant failure due to peri-implantitis, both from a clinical and from a socio-psychological attitude-related perspective.

Peri-implantitis and extracellular matrix antibodies: A case-control study.

Objective:The aim of this case–control study was to compare patients with a healthy peri-implant environment and patients affected by peri-implantitis, evaluating the occurrence of antibodies to extracellular matrix (ECM) molecules. The authors hypothesized the presence of ECM autoantibodies in serum of peri-implantitis patients.Materials and Methods:Patients were divided into two groups: one with dental implants with a diagnosis of peri-implantitis and one control group with implants classified as being “healthy.” Enzyme-linked immunosorbent assay was performed on patients’ sera to detect human antibodies to type I, III, IV, and V collagens, laminin, and fibronectin. Fisher exact test was performed to evaluate statistical association, with a significant P < 0.05.Results:Forty-two patients were enrolled in this study, 27 females (64.28%) and 15 males (35.72%) with a mean age of 53 ± 29.69 years (age range 32–74). The presence of antibodies to CIII was recorded in 6/21 (28.57%) patients of test group, compared to just 2/21 (9.52%) for the control group, showing a statistically significant difference (P < 0.05). Other antibodies tested were found to be not statistically significant or absent.Conclusions:Within the limitations of this study, it can be concluded that further studies, with larger sample and different design, are necessary to address the research purpose, evaluating possible associations between anti-ECM antibodies and peri-implantitis.

Risk Factors for Peri-Implantitis: Effect of History of Periodontal Disease and Smoking Habits. A Systematic Review and Meta-Analysis

ABSTRACTObjectivesThe purpose of this review was to evaluate whether history of periodontitis and smoking habits could represent a risk factor for peri-implantitis and implant loss.Material and MethodsThis systematic review followed PRISMA guidelines and was registered at the PROSPERO database [registration numbers CRD42016034160 (effect of history of periodontitis) and CRD42016033676 (effect of smoking)]. Broad electronic (MEDLINE) and manual searches were conducted among articles published from January 1st 1990 up to December 31st 2015, resulting in 49332 records for history of periodontitis and 3199 for smoking habits. Selection criteria included prospective studies comparing two cohorts of patients, with and without the investigated risk factor, with a minimum follow-up period of three years, and reporting data on peri-implantitis and implant loss occurrence. Considering that only prospective studies were included, dichotomous data were expressed as risk ratios and 95% confidence intervals.ResultsThree studies evaluating history of periodontitis (on which quantitative analysis was performed) and one study on smoking effect were included. Both implant and patient-based meta-analyses revealed a significantly higher risk of developing peri-implantitis in patients with a history of periodontitis compared with periodontally healthy subjects, but not a statistically significant increased risk for implant loss.ConclusionsThe outcomes of this systematic review indicate history of periodontitis as a possible risk factor for peri-implantitis, while insufficient data are present in literature to evaluate the role of smoking. However, available evidence is still weak and immature, and sound epidemiological studies are needed to analyse the specific contribution of these potential risk factors.

Expression of IL-6, IL-10, IL-17 and IL-33 in the peri-implant crevicular fluid of patients with peri-implant mucositis and peri-implantitis

ObjectivesThe aim of this study was to compare the levels of IL-6, IL-10, IL-17 and IL-33 in the peri-implantar crevicular fluid (PICF) and in parotid gland saliva (PGS) of healthy patients, and peri-implantitis and peri-implant mucositis patients. Materials and methodsThe PICF was collected from 40 implants as follows: 10 peri-implant mucositis patients, 20 peri-implantitis patients and 10 healthy patients. The PICF and PGS samples collected from each patient were quantified for IL-6, IL-10, IL-17 and IL-33 by enzymatic immunosorbent assay (ELISA). ResultsIL-6, IL-17 and IL-33 levels on PIFC were significantly higher in peri-implantitis group when compared to healthy group. IL-17 and IL-33 levels in PIFC were significantly higher in peri-implant mucositis group than in healthy group. There was no significant difference when comparing IL-6, IL-10, IL-17 and IL-33 levels in PGS among healthy, peri-implant mucositis and peri-implantitis groups. ConclusionsTherefore, as in patients with peri-implantitis there were significantly higher levels of IL-6, IL-17 and IL-33 in PICF, we believe that these cytokines were intensifying local inflammatory process, and contributing to clinical aspects such as increased marginal bleeding and probing depth found in patients with peri-implantitis. Furthermore, as IL-17 and IL-33 were increased in patients with peri-implant mucositis, hypothesized that these cytokines were also contributing to the inflammatory process observed in this disease.

The predictive value of microbiological findings on teeth, internal and external implant portions in clinical decision making.

The primary aim of this study was to evaluate 23 pathogens associated with peri-implantitis at inner part of implant connections, in peri-implant and periodontal pockets between patients suffering peri-implantitis and participants with healthy peri-implant tissues; the secondary aim was to estimate the predictive value of microbiological profile in patients wearing dental implants using data mining methods. Fifty participants included in the present case─control study were scheduled for collection of plaque samples from the peri-implant pockets, internal connection, and periodontal pocket. Real-time polymerase chain reaction was performed to quantify 23 pathogens. Three predictive models were developed using C4.5 decision trees to estimate the predictive value of microbiological profile between three experimental sites. The final sample included 47 patients (22 healthy controls and 25 diseased cases), 90 implants (43 with healthy peri-implant tissues and 47 affected by peri-implantitis). Total and mean pathogen counts at inner portions of the implant connection, in peri-implant and periodontal pockets were generally increased in peri-implantitis patients when compared to healthy controls. The inner portion of the implant connection, the periodontal pocket and peri-implant pocket, respectively, presented a predictive value of microbiologic profile of 82.78%, 94.31%, and 97.5% of accuracy. This study showed that microbiological profile at all three experimental sites is differently characterized between patients suffering peri-implantitis and healthy controls. Data mining analysis identified Parvimonas micra as a highly accurate predictor of peri-implantitis when present in peri-implant pocket while this method generally seems to be promising for diagnosis of such complex infections.

歯周炎患者におけるインプラント周囲炎の病態と治療法

歯周炎患者におけるインプラント周囲炎の病態と治療法

Interruption of Electrical Conductivity of Titanium Dental Implants Suggests a Path Towards Elimination Of Corrosion.

Peri-implantitis is an inflammatory disease that results in the destruction of soft tissue and bone around the implant. Titanium implant corrosion has been attributed to the implant failure and cytotoxic effects to the alveolar bone. We have documented the extent of titanium release into surrounding plaque in patients with and without peri-implantitis. An in vitro model was designed to represent the actual environment of an implant in a patient’s mouth. The model uses actual oral microbiota from a volunteer, allows monitoring electrochemical processes generated by biofilms growing on implants and permits control of biocorrosion electrical current. As determined by next generation DNA sequencing, microbial compositions in experiments with the in vitro model were comparable with the compositions found in patients with implants. It was determined that the electrical conductivity of titanium implants was the key factor responsible for the biocorrosion process. The interruption of the biocorrosion current resulted in a 4–5 fold reduction of corrosion. We propose a new design of dental implant that combines titanium in zero oxidation state for osseointegration and strength, interlaid with a nonconductive ceramic. In addition, we propose electrotherapy for manipulation of microbial biofilms and to induce bone healing in peri-implantitis patients.

Protein biomarkers and microbial profiles in peri-implantitis.

The aim of the present investigation was to determine the profile of peri-implant crevicular fluid (PICF) biomarkers combined with microbial profiles from implants with healthy peri-implant tissues and peri-implantitis to assess real-time disease activity. Sixty-eight patients were included in this cross-sectional study. They were divided into two groups: 34 patients with at least one healthy implant (control) and 34 with at least one peri-implantitis affected implant (test). Total DNA content and qPCR analysis for periodontal bacteria obtained from subgingival plaque samples (Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) and a PICF analysis for IL-1β, VEGF, MMP-8, TIMP-2, and OPG were performed. The individual and combined diagnostic ability of each biomarker for peri-implantitis and target bacterial species were analyzed. The mean concentration of IL-1β (44.6 vs. 135.8pg/ml; P<0.001), TIMP-2 (5488.3 vs. 9771.8pg/ml; P=0.001), VEGF (59.1 vs. 129.0pg/ml; P=0.012), and OPG (66.5 vs. 111.7pg/ml; P=0.050) was increased in the peri-implantitis patients. The mean expression of MMP-8 (6029.2 vs. 5943.1pg/ml; P=0.454) and did not reveal a meaningful difference among groups. Total bacterial DNA of selected microorganisms was associated with a threefold or greater increase in peri-implantitis although no statistical significant difference. The ability to diagnose diseased sites was enhanced by T.denticola combined with IL-1β, VEGF, and TIMP-2 PICF levels. The present data suggest that the increased levels of the selected PICF-derived biomarkers of periodontal tissue inflammation, matrix degradation/regulation, and alveolar bone turnover/resorption combined with site-specific microbial profiles may be associated with peri-implantitis and could have potential as predictors of peri-implant diseases.

Peri-implantitis: a complex condition with non-linear characteristics.

To cluster peri-implantitis patients and explore non-linear patterns in peri-implant bone levels. Clinical and radiographic variables were retrieved from 94 implant-treated patients (340 implants, mean 7.1±4.1years in function). Kernel probability density estimations on patient mean peri-implant bone levels were used to identify patient clusters. Inter-relationships of all variables were evaluated by principal component analysis; a k-nearest neighbours method was performed for supervised prediction of implant bone levels at the patient level. Self-similar patterns of mean bone level per implant from different jaw bone sites were examined and their associated fractal dimensions were estimated. Two clusters of implant-treated patients were identified, one at patient mean bone levels of 1.7mm and another at 4.0mm. Five of thirteen available variables (number of teeth, age, gender, periodontitis severity, years of implant service), were predictive for peri-implant bone levels. A high jaw bone fractal dimension was associated with less severe peri-implantitis. Non-linearity of peri-implantitis was evidenced by finding different peri-implant bone levels between two main clusters of implant-treated patients and among six different jaw bone sites. The patient mean peri-implant bone levels were predicted from five variables and confirmed complexity for peri-implantitis.

Prevalence of Peri-Implant Mucositis and Peri-Implantitis in Patients Treated with a Combination of Axial and Tilted Implants Supporting a Complete Fixed Denture.

Objectives. The aim of this retrospective study was to assess the incidence and prevalence of peri-implant mucositis and peri-implantitis in patients with a fixed full-arch prosthesis supported by two axial and two tilted implants. Materials and Methods. Sixty-nine patients were included in the study. Each patient received a fixed full-arch prosthesis supported by two mesial axial and two distal tilted implants to rehabilitate the upper arch, the lower arch, or both. Three hundred thirty-six implants for 84 restorations were delivered. Patients were scheduled for follow-up visits every 6 months in the first 2 years and yearly after. At each follow-up visit peri-implant mucositis and peri-implantitis were diagnosed if present. Results. The overall follow-up range was from 12 to 130 months (mean 63,2 months). Three patients presented peri-implantitis. The prevalence of peri-implant mucositis ranged between 0 and 7,14% of patients (5,06% of implants) while the prevalence of peri-implantitis varied from 0 to 4,55% of patients (3,81% of implants). Conclusions. The prevalence and incidence of peri-implant mucositis and peri-implantitis are lower than most of the studies in literature. Therefore this kind of rehabilitation could be considered a feasible option, on the condition of adopting a systematic hygienic protocol.

Factors influencing severity of peri-implantitis.

To retrospectively assess the influence of potential risk factors, primarily smoking and a prior history of periodontitis, on the severity of peri-implantitis in patients referred for treatment of peri-implantitis. Among 98 patients referred for treatment of peri-implantitis, 34 patients fulfilled the inclusion criteria: one or several implants with peri-implant marginal bone loss ≥2mm concomitant with bleeding and/or pus on probing. Information about health status, smoking habits, reason for tooth loss, and performed implant treatment were obtained from the patient charts and interviews. Moreover, a detailed extra- and intraoral examination was performed, including intraoral radiographs of all implants. Risk factors were evaluated by a two-way anova at patient level. Smoking and a prior history of periodontitis were significant risk factors for increased severity of peri-implantitis. Furthermore, the presence of both smoking and a prior history of periodontitis did not further increase the severity of peri-implantitis, as compared to either of these two factors alone. Poor marginal fit of the suprastructure and extensive gingival imitations on implant-supported fixed full prostheses may also be potential risk factors. The study indicated that smoking and a prior history of periodontitis were important risk factors for increased severity of peri-implantitis, while concomitant presence of these two risk factors did not further increase the severity of peri-implantitis, as compared to either of these two risk factors alone. Therefore, early diagnosis and adequate treatment of peri-implantitis are important in patients with a prior history of periodontitis and in smokers to minimize the risk of advanced peri-implantitis in conjunction with focus on known risk factors, including meticulous infection control before implant treatment and a systematic maintenance care program.

CD14 and TNFα single nucleotide polymorphisms are candidates for genetic biomarkers of peri-implantitis

This study aims to investigate whether CD14-159 C/T and TNFα -308 A/G single nucleotide polymorphisms are associated with peri-implantitis and to evaluate their effects on bone resorption by correlating with local levels of receptor activator nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG). Study population included 369 Southeastern Europe Caucasians (180 with peri-implantitis and 189 with healthy peri-implant tissues). Genotyping was performed using polymerase chain reaction from the periphery blood samples, while RANKL and OPG were evaluated in peri-implant crevicular fluid specimens using enzyme-linked immunosorbent assay. Analysis of CD14-159 C/T polymorphism showed that genotype of CC nucleic acid combination was associated with peri-implantitis demonstrating a fivefold increased risk in these carriers. Furthermore, for TNFα -308 A/G polymorphisms, it was evidenced that AG genotype was associated with peri-implantitis and a fivefold increased risk in these carriers. Peri-implantitis patients with CC genotype at CD14-159 exhibited significantly higher concentrations of RANKL and relative ratio RANKL/OPG when compared to patients with CT genotype, while concentration of biomarkers between different genotypes at TNFα -308 remained insignificant. Within the limitations of the study, we can conclude that CD14-159 C/T and TNFα -308 A/G polymorphisms are associated with peri-implantitis and may present biomarkers for peri-implantitis. Investigated genetic markers might serve as precious parameters in clinical practice in course of treatment planning and prognosis, since preventive and treatment approach could be positively shifted and adjusted depending on present genotype.

Prevalence of peri-implant inflammatory disease in patients with a history of periodontal disease who receive supportive periodontal therapy.

To describe the status of implants in periodontally compromised patients who regularly receive supportive periodontal therapy (SPT) and to determine the factors associated to peri-implant inflammatory disease in those patients. Clinical and radiographic data of implants in periodontal patients who, after being treated and included in a SPT programme, wore implant prostheses for at least 6 months were recorded. The implants were classified according to the criteria of the 6th European Workshop on Periodontology in health, mucositis and peri-implantitis. Logistic regression analysis was performed to analyse the individual and adjusted effects of each study variable on mucositis or peri-implantitis, using SUDAAN to account for clustering (multiple implants within the patient). A total of 786 implants were placed in 239 patients. At patient level, 60.3%, 24.7% and 15.1% were classified as healthy, mucositis and peri-implantitis patients, respectively. At implant level, the respective percentages were 77.4%, 12.8% and 9.8%. For mucositis, at implant level, the adjusted ORs indicate a significant association with plaque index (P = 0.050), type of periodontitis (P = 0.030) and location (P = 0.045). For peri-implantitis, the adjusted ORs indicate a significant association with plaque index (P < 0.001) and location (P = 0.002). The prevalence of peri-implant inflammatory disease in periodontal patients who regularly undergo SPT is clinically significant. The factors associated with peri-implant inflammatory disease were plaque index and implant location, and mucositis was also affected by the type of periodontitis the patient had.

Prevalence of peri-implantitis in patients with implant-supported fixed prostheses.

The purpose of this study was to evaluate periimplantitis prevalence in patients using implant-supported fixed prostheses that did not have any routine maintenance care. A total of 161 implants (27 patients) were evaluated in patients using implant-supported fixed prostheses. Collected data included information related to patient general health and local factors such as characteristics of implants, time in function, type of loading, positioning, Modified Bleeding Index, bacterial plaque, bleeding on probing (BOP), marginal recession, probing depth (PD), keratinized mucosa, and radiographic bone loss (BL). Factors related to the prostheses were also evaluated. The exclusion criteria were patients that have had any follow-up visit for plaque control of the prosthesis and/or the implants. From a total of 161 implants, 116 (72%) presented without peri-implantitis (PD > 4 mm + BOP + BL > 2 mm) while 45 (28%) had some sign of the disease. Implants placed in the maxilla were 2.98 times more likely to develop the disease (P < .05). Moreover, patients aged ≤ 60 years old were 3.24 times more likely to develop peri-implantitis (P < .05). Another analysis with statistical relevance (P < .05) was that implants with less than 3 mm interimplant distance were three times more likely to have peri-implantitis. There was no statistical relevance considering other analyses. It can be concluded that patients aged ≤ 60 years have a greater chance of presenting periimplantitis, as well as for implants positioned in the maxilla and those placed with an interimplant distance < 3 mm.

The Therapy of Peri-implantitis: A Systematic Review

To evaluate the success of treatments aimed at the resolution of peri-implantitis in patients with osseointegrated implants. The potentially relevant literature was assessed independently by two reviewers to identify case series and comparative studies describing the treatment of peri-implantitis with a follow-up of at least 3 months. Medline, Embase, and The Cochrane Library were searched. For the purposes of this review, a composite criterion for successful treatment outcome was used which comprised implant survival with mean probing depth < 5 mm and no further bone loss. A total of 43 publications were included: 4 papers describing 3 nonsurgical case series, 13 papers describing 10 comparative studies of nonsurgical interventions, 15 papers describing 14 surgical case series, and 11 papers describing 6 comparative studies of surgical interventions. No trials comparing nonsurgical with surgical interventions were found. The length of follow-up varied from 3 months to 7.5 years. Due to the heterogeneity of study designs, peri-implantitis case definitions, outcome variables, and reporting, no meta-analysis was performed. Eleven studies could be evaluated according to a composite success criterion. Successful treatment outcomes at 12 months were reported in 0% to 100% of patients treated in 9 studies and in 75% to 93% of implants treated in 2 studies. Commonalities in treatment approaches between studies included (1) a pretreatment phase, (2) cause-related therapy, and (3) a maintenance care phase. While the available evidence does not allow any specific recommendations for the therapy of peri-implantitis, successful treatment outcomes at 12 months were reported in a majority of patients in 7 studies. Although favorable short-term outcomes were reported in many studies, lack of disease resolution as well as progression or recurrence of disease and implant loss despite treatment were also reported. The reported outcomes must be viewed in the context of the varied peri-implantitis case definitions and severity of disease included as well as the heterogeneity in study design, length of follow-up, and exclusion/inclusion criteria.

Receptor activator of nuclear factor kappa-B gene polymorphisms in Iranian periodontitis and peri-implantitis patients.

Peri-implantitis and periodontitis are inflammatory and infectious diseases of implant and tooth-supporting tissues. Recently, the role of gene polymorphisms of immune response components in the relevant pathogenesis has been investigated. The present study was the first to evaluate the relationship between two known single nucleotide polymorphisms (SNPs) of the receptor activator of nuclear factor kappa-β (RANK) gene (rs3018362 and rs35211496) in chronic periodontitis and peri-implantitis patients in an Iranian population. Eighty-one periodontally healthy patients, 38 patients with peri-implantitis, and 74 patients with chronic periodontitis were enrolled in this study. DNA was extracted from blood arm vein samples by using Miller's salting out technique according to the manufacturer's instructions given in the extraction kit. The concentration of DNA samples was measured using a spectrophotometer. The genetic polymorphisms of the RANK gene were evaluated using a competitive allele specific polymerase chain reaction (KBioscience allele specific PCR) technique. Differences in the frequencies of genotypes and alleles in the diseased and healthy groups were analyzed using chi-squared statistical tests (P<0.05). Analysis of rs35211496 revealed statistically significant differences in the expression of the TT, TC, and CC genotypes among the three groups (P=0.00). No statistically significant difference was detected in this respect between the control group and the chronic periodontitis group. The expression of the GG, GA, and AA genotypes and allele frequencies (rs3018362) showed no statistically significant difference among the three groups (P=0.21). The results of this study indicate that the CC genotype of the rs35211496 RANK gene polymorphism was significantly associated with peri-implantitis and may be considered a genetic determinant for peri-implantitis, but this needs to be confirmed by further studies in other populations.

Matrix Metalloproteinase-8 Levels in Peri-implant Sulcus Fluid Adjacent to Titanium and Zirconium Nitride Surfaces

During host interaction against oral biofilm, matrix metalloproteinase-8 (MMP-8) is activated, leading to collagenolytic destruction of host tissues. In periimplantitis patients, the active form of MMP-8 is elevated in peri-implant sulcus fluid (PISF). In this study, MMP-8 in PISF from titanium abutments and those coated with zirconium nitride (ZrN) was compared in vivo in a split-mouth design in 60 patients at 6 weeks, 6 months, and 12 months after prosthetic restoration. At each time point, MMP-8 values in PISF differed significantly between titanium and ZrN abutment surfaces. For example, mean MMP-8 values reached 10 to 12 ng/mL in titanium and only 6.6 to 7.5 ng/mL with ZrN. Similarly, the 75th percentile MMP-8 concentrations were 12 to 15 ng/mL and 8 to 9 ng/mL for titanium and ZrN, respectively. Based on this finding, ZrN-coated abutments seem to exert a beneficial effect regarding collagenolytic tissue destruction driven by MMP-8 in situ.

Antibiotic resistance in human peri‐implantitis microbiota

Because antimicrobial therapy is often employed in the treatment of infectious dental implant complications, this study determined the occurrence of in vitro antibiotic resistance among putative peri-implantitis bacterial pathogens. Submucosal biofilm specimens were cultured from 160 dental implants with peri-implantitis in 120 adults, with isolated putative pathogens identified to species level, and tested in vitro for susceptibility to 4mg/l of doxycycline, 8mg/l of amoxicillin, 16mg/l of metronidazole, and 4mg/l of clindamycin. Findings for amoxicillin and metronidazole were combined post-hoc to identify peri-implantitis species resistant to both antibiotics. Gram-negative enteric rods/pseudomonads were subjected to ciprofloxacin disk diffusion testing. One or more cultivable submucosal bacterial pathogens, most often Prevotella intermedia/nigrescens or Streptococcus constellatus, were resistant in vitro to clindamycin, amoxicillin, doxycycline, or metronidazole in 46.7%, 39.2%, 25%, and 21.7% of the peri-implantitis subjects, respectively. Only 6.7% subjects revealed submucosal test species resistant in vitro to both amoxicillin and metronidazole, which were either S.constellatus (one subject) or ciprofloxacin-susceptible strains of gram-negative enteric rods/pseudomonads (seven subjects). Overall, 71.7% of the 120 peri-implantitis subjects exhibited submucosal bacterial pathogens resistant in vitro to one or more of the tested antibiotics. Peri-implantitis patients frequently yielded submucosal bacterial pathogens resistant in vitro to individual therapeutic concentrations of clindamycin, amoxicillin, doxycycline, or metronidazole, but only rarely to both amoxicillin and metronidazole. Due to the wide variation in observed drug resistance patterns, antibiotic susceptibility testing of cultivable submucosal bacterial pathogens may aid in the selection of antimicrobial therapy for peri-implantitis patients.

Clinical outcome of a nonsurgical and surgical treatment protocol in different types of peri-implantitis: a case series.

The replacement of missing teeth with dental implants has been standard practice in dentistry for many years. The success of dental implants depends on many factors, among which the diagnosis, clinical severity, and treatment of peri-implant diseases play a key role. In this prospective case series, the influence of cumulative treatment modalities on peri-implantitis with and without pus formation on clinical outcome was assessed. During 2010, 28 patients were referred for peri-implantitis treatment. They presented two different types of peri-implant diseases: peri-implantitis with (17 implants) or without pus formation (33 implants). After microbiologic diagnosis, all patients were treated at baseline with full-mouth scaling and root planing. Two months later, further full-mouth scaling and root planing and additional antimicrobial photodynamic therapy (aPDT) was applied. Four months after baseline, patients with pus formation additionally underwent access flap surgery. Active human matrix metalloproteinase-8 (aMMP-8) levels were measured in eluates before and after all treatment modalities and 7 months after baseline. Clinical parameters (probing depth, bleeding on probing) and aMMP-8-levels improved in both groups after treatment and the final examination. In periimplantitis patients without pus formation, all parameters decreased after full-mouth scaling and root planing and the additional aPDT and no surgery was necessary to improve the parameters. In patients with pus formation, the parameters decreased only after access flap surgery. The presence of pus influences the clinical outcome of the treatment of peri-implant diseases. Whereas peri-implantitis cases without pus formation can be successfully managed nonsurgically, peri-implantitis with pus formation can be effectively treated after an additional observation time of 3 months postoperatively only with additional flap surgery.