Risk Indicators For Peri-implantitis Research Articles

Prevalence and risk indicators of peri-implantitis: a university based cross-sectional study.

To assess the prevalence of peri-implantitis and identify risk and protective indicators of peri-implantitis in a population that underwent implant therapy in a university dental clinic. Randomly selected patients from a postgraduate university dental clinic were invited to participate. Clinical and radiographic examinations were recorded. Peri-implantitis was defined as the presence of bleeding and/or suppuration on probing, probing depths of ≥ 6 mm, and bone loss ≥ 3 mm. Patient-, implant-, and bone- related factors were recorded and analyzed using a multivariate logistic regression analysis. A total of 355 dental implants placed in 108 patients and exhibiting at least 1 year loading time were included. The prevalence of peri-implantitis was 21.3% at patient-level, while 10.7% at implant-level. Simultaneous guided bone regeneration (OR 2.76, 95% CI 1.07-7.12, P = .035), recurrent periodontitis (OR 3.11, 95% CI 1.02-9.45, P = .045) and significant medical history (OR 2.86, 95% CI 1.08-7.59, P = .034) were identified as risk indicators for peri-implantitis. The mean peri-implant bone loss was estimated to be 2.18 ± 1.57 mm for the total number of implants, whereas implants diagnosed with peri-implantitis demonstrated 4.42 ± 1.12 mm in a time period between 12 to 177 months. Within the limitations of the study, the prevalence of peri-implantitis in a cohort receiving dental implant therapy at a university dental clinic was 10.7% at implant level and 21.3% at patient level. Patient-reported systemic comorbidities and recurrent periodontitis as well as implants placed in ridge augmented sites were associated with greater risk of peri-implantitis.

Diffuse Sclerosing Osteomyelitis: A Potential Risk Indicator for Peri-implantitis? A Case Series.

To propose diffuse osteomyelitis as risk indicator for peri-implantitis following the loss of several dental implants in patients that present with highly sclerotic bone areas. A total of six "nightmare cases"-three of which were treated at the Department of Periodontology of the University Hospitals of the Catholic University Leuven and three of which were referred there for a second opinion-were retrospectively analyzed using radiographs obtained via contact with referring clinicians in order to fully reconstruct the treatment pathway and dental history for each of these patients. All patients suffered from early implant failures and/or severe peri-implantitis with bone loss and crater formation up to the apical level, as well as the loss of all or nearly all implants. Re-examination of their preand postoperative CBCTs, in combination with several bone biopsies, confirmed the diagnosis of a diffuse sclerosing osteomyelitis in the treated area. Osteomyelitis could be linked to a longstanding history of chronic and/or therapyresistant periodontal/endodontic pathology. The current retrospective case series seems to suggest that diffuse osteomyelitis should be considered as a risk indicator for severe peri-implantitis. Int J Oral Maxillofac Implants 2023;38:503-515. doi: 10.11607/jomi.9773.

Interproximal implant thread exposure after initial bone remodeling as a risk indicator for peri-implantitis.

Due to the clinical challenges involved in successfully treating peri-implantitis, it is imperative to identify patient- and implant-level risk factors for its prevention. The main goal of this retrospective longitudinal radiographic and clinical study was to investigate whether interproximal radiographic implant thread exposure after physiological bone remodeling may be a risk factor for peri-implantitis. The secondary goal was to evaluate several other potential risk indicators. Of 4325 active dental school patients having implants placed, 165 partially edentulous adults (77 men, 88 women) aged 30-91 with ≥2years of follow-up upon implant restoration were included. Implants with ≥1 interproximal thread exposed (no bone-to-implant contact) (n=98, 35%) constituted the test group and those without exposed threads (n=182, 65%) the control group. Descriptive, binary, and multivariate regression analyses were evaluated for goodness of fit. Wald tests were used to evaluate for significance set at 0.05. Of the 280 implants (98 test, 182 control), 8 (2.9%) failed over a mean follow-up period of 7.67 (±2.63) years, and 27 implants (19 test, 8 control) developed peri-implantitis, with the exposed group having eight-fold (7.82 times) adjusted greater odds than the non-exposed. The risk increased four-fold (3.77 times) with each thread exposed. No other patient- or implant-related potentially confounding risk factors were identified. Exposed interproximal implant threads after physiologic bone remodeling may be an independent risk indicator for incident peri-implantitis. Hence, clinicians should closely monitor patients with implant threads that have no bone-to-implant contact for incident peri-implantitis.

Psychological risk indicators for peri-implantitis: A cross-sectional study.

The aim of this analytical cross-sectional study was to evaluate the association between peri-implantitis and psychological distress, and potentially related/mediating factors such as general health, bruxism, and lifestyle factors. Patients who received dental implants at a private practice in the Netherlands between January 2011 and January 2014 were recalled on a 5-year clinical and radiographic follow-up examination. Presence of peri-implantitis was examined, and patients completed questionnaires measuring psychological distress (Symptom Checklist [SCL]-90), bruxism, general health, and lifestyle factors. Associations between the self-reported factors and peri-implantitis were analysed with univariate and multivariate logistic regression models. A total of 230 patients (with 347 implants) were included in the analysis. Prevalence of (mild to severe) peri-implantitis was 30% (69 patients). Variables that showed a significant univariable association with peri-implantitis (p< .10) were the SCL-90 subdomain depression, smoking, current medical treatment, and lung problems. In the multivariate regression analysis, depression was the only variable that was significantly associated with peri-implantitis (p< .05). The presence of depressive symptoms is a risk indicator for peri-implantitis. Recognizing the potential negative impact of depressive symptoms may allow for better identification of high-risk patients.

The effect of conventional versus electronic cigarette use on treatment outcomes of peri-implant disease

AimTo compare changes in clinical periodontal parameters (gingival consistency, colour, BOP, PI, PD) and changes of salivary inflammatory biomarkers (IL-1 β, IL-6, MMP-8, TNF- α and TIMP-1 between conventional, electronic cigarette smokers and non-smokers after peri-implant treatment.MethodsStudy participants were grouped into three groups (i) Conventional cigarette smokers (ii) Electronic cigarette smokers and (iii) non-smokers respectively. A total of 60 adult patients aged (40–56 years) with 60 implants with active per-impantitis was included.Clinical and Biological parameters were evaluated before surgical treatment at baseline, one, six and twelve month post treatment. Pearson’s chi-square test was used to compare the distribution of the categorical while Two-way repeated analysis of variance was used to compare the mean values of quantitative outcome variables among all study groups across the 4 time points.ResultsA total of 60 subjects (60 implants) were selected and classified into three groups as per their smoking method 20 participants in each group with one single targeted implant diagnosis with active peri-implantitis. The gingival colour, the change was statistically significant at one year of post treatment.The gingival consistency distribution across the three groups is not statistically significant at baseline, but it is statistically significant at one-month (p = 0.001), six months (p = 0.029) and at the completion of one-year (p = 0.018) post treatment. The plaque index of 100% of non-smokers had changed to ‘0’ and 35% change in cigarettes and 30% change in electronic smokers which is statistically significant (p = 0.016).The prevalence of BOP was observed in the three groups as 72%, 76.5% and 88.9% at baseline. The mean values of PD have shown statistically significant change across the three groups over the four-time intervals of observation (p = 0.024). The comparison of mean values of IL-1 β, IL-6 and TIMP-1 has shown statistically significant change across the three groups over the four intervals of observation (p < 0.0001).ConclusionsElectronic cigarette smoking was found to be most prevalent risk indicator for peri-implantitis. Compromised response of peri-implantitis treatment both clinically and biologically was found more among electronic cigarette smokers when compared to conventional cigarette smokers and non-smokers.Trial registration: This case-control study was conducted at King Saud University’s Dental College, Riyadh, Saudi Arabia, in accordance with “Helsinki Declaration of Human Studies” and approved by the Institutional Review Board (Reference no: 87563).

Prevalence and risk indicators for peri-implant diseases: A literature review.

Peri-implant diseases are known as undesirable conditions that can occur after implant therapy. Although several risk indicators are becoming clear, the causes of peri-implant diseases have not been completely investigated. The purpose of this review was to summarize the prevalence and risk indicators for peri-implant diseases by referring to current papers from various angles. Many studies have reported the varied prevalence of peri-implant mucositis (23.9%–88.0% at the patient level and 9.7%–81.0% at the implant level) and peri-implantitis (8.9%–45% at the patient level and 4.8%–23.0% at the implant level). Additionally, several studies concluded that poor oral hygiene and lack of regular maintenance were strongly correlated with the development of both peri-implant mucositis and peri-implantitis. Diabetes and a history of periodontitis were revealed as risk indicators for peri-implantitis. However, there was no definitive conclusion about the correlations between peri-implant diseases and other factors such as smoking, the shape of the implant superstructure, and the condition of the keratinized mucosa. Further studies useful for evidence-based decision-making are needed for predictable implant therapy in the long term.

Role of thin gingival phenotype and inadequate keratinized mucosa width(

There is growing evidence on the impact of thin gingival phenotype (TnP) and inadequate keratinized mucosa width (KMW<2mm) around dental implants on peri-implant health. This study investigated the role of TnP and inadequate KMW(<2mm) as risk indicators for peri-implantitis and mucositis and on dental patient-reported outcomes. Sixty-three patients with 193 implants (mean follow-up of 6.9 ± 3.7 years) were given a clinical and radiographic examination and a questionnaire to assess patient awareness of food impaction and pain/discomfort. Chi-squared tests and regression analysis for clustered data were used to compare outcomes. Implants with TnP had a statistically higher prevalence of peri-implantitis (27.1%versus 11.3%; PR, 3.32; 95% confidence interval (CI), 1.64-6.72; P=0.001) peri-implant mucositis (42.7%versus 33%; PR, 1.8; 95% CI, 1.12-2.9; P=0.016) and pain/discomfort during oral hygiene (25%versus 5%; PR, 3.7; 95% CI, 1.06-12.96; P=0.044) than thick phenotype. Implants with inadequate KMW had a statistically higher prevalence of peri-implantitis (24.1%versus 17%; PR, 1.87; 95% CI, 1.07-3.25; P=0.027) and peri-implant mucositis (46.6%versus 34.1%; PR, 1.53; 95% CI, 1-2.33; P=0.05) and pain/discomfort during oral hygiene (28%versus 10%; PR, 2.37; 95% CI, 1.1-5.1; P=0.027) than the adequate KMW. TnP was strongly associated with inadequate KMW (PR=3.18; 95% CI, 1.69-6.04; P<0.001). TnP and inadequate KMW(<2mm) may be significant risk indicators for peri-implant disease and pain/discomfort during brushing.

Removable denture is a risk indicator for peri-implantitis and facilitates expansion of specific periodontopathogens: a cross-sectional study

BackgroundThe prevalence of peri-implantitis ranges between 7 and 38.4% depending on risk indicators such as smoking, diabetes mellitus, lack of periodontal maintenance program, and history or presence of periodontitis. Currently, the possible effect of the type of superstructure on peri-implant health is unclear. This cross-sectional study aims to investigate the influence of the superstructure on the prevalence of peri-implant mucositis, peri-implantitis and peri-implant dysbiosis.MethodsDuring a 32-month recruitment period dental implants were assessed to diagnose healthy peri-implant tissues, mucositis or peri-implantitis. The study included 1097 implants in 196 patients. Out of all peri-implantitis cases 20 randomly chosen submucosal biofilms from implants with fixed denture (FD) originating from 13 patients and 11 biofilms from implants with removable dentures (RD) originating from 3 patients were studied for microbiome analysis. Composition of transcriptionally active biofilms was revealed by RNAseq. Metatranscriptomic profiles were created for thirty-one peri-implant biofilms suffering from peri-implantitis and microbiome changes associated with superstructure types were identified.Results16.41% of the implants were diagnosed with peri-implantitis, 25.00% of implants with RD and 12.68% of implants with FD, respectively. Multivariate analysis showed a significant positive association on patient (p = < 0.001) and implant level (p = 0.03) between the prevalence of peri-implantitis and RD. Eight bacterial species were associated either with FD or RD by linear discriminant analysis effect size method. However, significant intergroup confounders (e.g. smoking) were present.ConclusionsWithin the limitations of the present work, RDs appear to be a risk indicator for peri-implantitis and seem to facilitate expansion of specific periodontopathogens. Potential ecological and pathological consequences of shift in microbiome from RDs towards higher activity of Fusobacterium nucleatum subspecies animalis and Prevotella intermedia require further investigation.

Prevalence and risk indicators of peri‐implantitis: an university‐representative cross‐sectional study

Background: Despite some epidemiological studies are available on the prevalence and risk indicators of peri-implant diseases, there is still a need of studies in different settings since the role of some risk factors is still putative. To minimize selection bias, representative samples should be used. However, only two epidemiological studies have analysed the epidemiology of peri-implantitis using representative samples so far, both referring to private settings and not to university clinics. Aim/Hypothesis: The aim of this cross-sectional study was to analyse the prevalence of peri-implantitis and its risk indicators in a university-based representative sample. Materials and Methods: 240 patients who received at least one dental implant in an EFP Program in Periodontology between the years 2000 and 2017 and in function by at least 1 year were randomly selected. Those who accepted to participate received a detailed medical and dental history assessment, a clinical examination and a standardized peri-apical radiograph. Peri-implantitis was both defined according to the 2018 World Workshop (bone levels≧3 mm & BoP/SoP) and according to the case definitions of Sanz & Chapple 2012 (bone levels≧2 mm & BoP/SoP). The prevalence of peri-implantitis was then calculated, as well as a multilevel multivariate logistic regression analysis was carried out to identify the risk indicators associated with peri-implantitis. Results: 109 patients with a total of 508 implants accepted to participate. The prevalence of peri-implantitis according to the definition of the 2018 World Workshop was 6.52% at implant-level and 16.19% at patient-level. The prevalence of peri-implantitis according to the Sanz & Chapple 2012 case definition was 33.86% at implant-level and 60.75% at patient level. The following factors were identified as risk indicators for peri-implantitis (Sanz & Chapple 2012 case definition): - smoking (OR = 3.3; 95% CI: 1.2–8.9); - diabetes (OR = 12.66; 95% CI: 1.78–90.16); - moderate/severe periodontitis (AAP) (OR = 3.7; 95% CI: 1–40–9.74); - use of interproximal brushes (OR = 0.18; 95% CI: 0.06–0.62); - implant brand (Nb vs. S: OR = 5.12; 95% CI: 1.90 – 13.90); - type of super-structure (multi-unit restorations vs. single crown: OR = 2.37; 95% CI: 1.22–4.60); - plaque (six sites vs. 0 sites: OR = 3.4; 95% CI: 1.02–11.32). Conclusions and Clinical Implications: According to the present study, peri-implantitis is a highly prevalent disease at patient-level. Diabetes, smoking, moderate/severe periodontitis, implant brand, multi-unit restorations and plaque were identified as risk indicators for peri-implantitis, while the use of interproximal brushes was inversely associated. Randomized clinical studies or, when not possible for ethical reasons prospective cohort studies, are needed to demonstrate true causality of the identified risk indicators. Keywords: peri-implantitis, cross-sectional, risk indicators, risk factor, prevalence.

Peri implantitis: An overview

Biologic complications associated with dental implants primarily relate to infection in the soft and hard tissue around implants known as peri implant mucositis and peri implantitis respectively. Prevalence of peri implantitis rates upto 60% and lead to the loss of implants. Current evidence points to poor oral hygiene, history of periodontitis, and smoking as being the strongest risk indicators for peri implantitis along with the factors affecting plaque accumulation and removal like design of prosthesis and excess cement. Different methods are used to assess peri implant tissue health and to diagnose these entities. Various treatment modalities are available including conservative and surgical approaches for the treatment of peri implant diseases so as to achieve reosseointegration of the exposed implant surface, being the ultimate goal. The aim of this review is to provide an overview regarding etiology, diagnosis and treatment of peri implantitis. Keywords: Mouthwash, Chlorhexidine, Stains, Bacteria.

Prevalence of peri-implant disease and risk indicators in a Japanese population with at least 3years in function-A multicentre retrospective study.

The aim of this study was to evaluate the prevalence of peri-implant disease and analyze risk indicators in Japanese subjects with ≥3years of implant function. Five hundred and forty-three subjects treated with 1,613 implants were evaluated. Information was collected about the patients' physical and dental history, as well as implant details. Peri-implant evaluation included probing depth, bleeding on probing (BoP), suppuration (Sup), and keratinized tissue width. Bone loss was calculated from intra-oral radiographs taken after 1year and more than 3years of function. Implants were classified into three groups: healthy, peri-implant mucositis (BoP without bone loss), and peri-implantitis (BoP and/or Sup with bone loss >1mm). These data were analyzed by multivariable multinomial logistic regression. The prevalence of peri-implant mucositis and peri-implantitis at the subject level was 23.9% and 15.8%, respectively. An association was found between peri-implant mucositis and plaque control record (PCR) >20% and keratinized tissue width <2mm. Peri-implantitis was associated with PCR >20%, smoking, insertion in the maxilla, and keratinized tissue width <2mm. Within the limitations of this study, the prevalence of peri-implant diseases was elucidated in a Japanese population. Peri-implant mucositis was associated with poor oral hygiene and less keratinized tissue. Poor oral hygiene, smoking, insertion in the maxilla, and less keratinized tissue were risk indicators for peri-implantitis.

Longitudinal study on risk indicators for peri-implantitis using survival-time analysis

PurposeThe purpose of this study was to evaluate the incidence of peri-implantitis and to identify potential associated risk indicators. MethodsThis longitudinal study included 477 patients treated with 1420 implants. Medical and dental histories were evaluated in all patients. The location, size, connection type, surgical protocol, use of prosthesis splinting and fixation type were evaluated for each implant. In peri-implant evaluation, minimum keratinized tissue width around implants, peri-implant probing depths, peri-implant bleeding and peri-implant suppuration were assessed. Bone resorption around implants was evaluated with intraoral radiographs at baseline and at follow-up examinations. The study endpoint was peri-implantitis, which was defined as the presence of bleeding on probing and/or suppuration with bone resorption >1mm, in accordance with previous studies. Data were analyzed with mixed-effects Cox models. ResultsPeri-implantitis occurred in 15.3% of patients and 9.2% of implants. The overall 5- and 10-year cumulative implant survival rates were 0.95 (95% confidence interval [CI]: 0.93–0.96) and 0.83 (95% CI: 0.8–0.87), respectively. Age (hazard ratio [HR]=0.94, 95% CI: 0.90–0.98, p<0.01), plaque control record >20% (HR=2.61, 95% CI: 1.02–6.67, p=0.04), maxillary placement (HR=1.90, 95% CI: 1.11–3.23, p=0.02) and number of occlusal supports (HR=0.87, 95% CI: 0.77–0.99, p=0.03) were significantly correlated with peri-implantitis development. ConclusionsWithin the limitations of this longitudinal study on risk indicators for peri-implantitis, age, inadequate plaque control, insertion in the maxilla and less occlusal support of natural teeth correlated with peri-implantitis development.

Prevalence, extent and severity of peri-implant diseases. Across-sectional study based on a university setting in Brazil.

Peri-implant diseases are a growing concern among clinicians. Epidemiological studies following recently recommended case definitions for peri-implant diseases are emerging worldwide. Although a small number of studies on the prevalence of peri-implant diseases has been conducted in Brazil, no information on the extent and severity of the condition has been made available so far. The objective of this study was to estimate the prevalence, extent and severity of peri-implant diseases in patients treated in a university setting in Brazil. Patients with dental implants with at least 1year in function were clinically and radiographically examined and classified according to recently recommended case definitions. A descriptive analysis on the prevalence, extent and severity of the peri-implant status at patient and implant level was performed. Risk indicators for peri-implantitis were also identified with binary logistic regression analysis. Of the 211 participating individuals, 4 (1.9%) presented peri-implant health, 8 (3.8%) clinical stability, 115 (54.5%) mucositis and 84 (39.8%) peri-implantitis. Of the 748 implants analyzed, 47 (6.3%) presented peri-implant health, 30 (4%) clinical stability, 518 (69.2%) mucositis and 153 (20.5%) peri-implantitis. The extent of implants with peri-implantitis and peri-implant mucositis was 41.5% and 90.4%, respectively. Severe peri-implantitis was found in 36 patients (17.1%) and 67 implants (9%). Gender male, number of implants ≥4, implants installed in the maxilla, cemented prosthesis and keratinized mucosa width <2mm were significantly associated with the event peri-implantitis. In the studied population, the prevalence, extent and severity of the peri-implant diseases were similar to those reported elsewhere. Peri-implant diseases were a common finding, with only 5.7% of patients and 10.3% of implants presenting peri-implant health or clinical stability. About 17% of patients studied presented the severe form of peri-implantitis.

Risk indicators for Peri-implantitis. Across-sectional study with 916 implants.

The aim of this study was to identify systemic and local risk indicators associated with peri-implantitis. One hundred eighty-three patients treated with 916 osseointegrated titanium implants, in function for at least 1year, were included in the present study. The implants were installed at the Foundation for Scientific and Technological Development of Dentistry (FUNDECTO) - University of Sao Paulo (USP) - from 1998 to 2012. Factors related to patient's systemic conditions (heart disorders, hypertension, smoking habits, alcoholism, liver disorders, hepatitis, gastrointestinal disease, diabetes mellitus I and II, hyperthyroidism or hypothyroidism, radiation therapy, chemotherapy, menopause, osteoporosis, active periodontal disease, history of periodontal disease and bruxism), implant's characteristics (location, diameter, length, connection, shape, and antagonist), and clinical parameters (wear facets, periodontal status on the adjacent tooth, plaque accumulation on the adjacent tooth, modified plaque index, sulcus bleeding index, probing depth, bleeding on probing, width of keratinized tissue and marginal recession). An increased risk of 2.2 times for history of periodontal disease (PD), 3.6 times for cemented restorations compared to screw-retained prostheses, 2.4 times when wear facets were displayed on the prosthetic crown and 16.1 times for total rehabilitations when compared to single rehabilitations were found. Logistic regression analysis did not show any association between the implant's characteristics and peri-implantitis. A history of periodontal disease, cemented prostheses, presences of wear facets on the prosthetic crown and full mouth rehabilitations were identified as risk indicators for peri-implantitis. Implants' characteristics were not related to the presence of peri-implantitis.

The patient undergoing implant therapy. Summary and consensus statements. The 4th EAO Consensus Conference 2015

The assignment for this working group was to update the existing knowledge regarding factors considered being of special relevance for the patient undergoing implant therapy. This included areas where conflicting opinions exists since long or recently has been expressed, like the role of antibiotic prophylaxis in dental implant surgery and peri-implantitis. Also areas with growing interest and concern such as patient-reported outcome measures (PROMs) and health-economy was included in this review. The literature in the respective areas of interest (antibiotic prophylaxis, peri-implantitis, patient-reported outcome measurements and health-economic aspects) was searched using different strategies for the different papers. Search strategies ranged from a complex systematic review to systematic- and narrative reviews, depending on subject and available literature. All collected material was critically reviewed. Four manuscripts were subsequently presented for group analysis and discussion and plenum discussions and concensus approval. The selected areas were considered to be of key importance and relevance for the patient undergoing implant therapy. The results and conclusions of the review process are presented in the respective papers. The group's conclusions, identified knowledge gaps, directions for future research and concensus statements are presented in this article. The following reviews were available for group discussions and the foundation for subsequent plenary sessions: Lund B, Hultin M, Tranaeus S, Naimi-Akbar A, Klinge B. (2015) Perioperative antibiotics in conjunction with dental implant placement. A complex systematic review. Renvert S & Quirynen M. (2015) Risk indicators for peri-implantitis. A narrative review. De Bruyn H, Raes S, Matthys C, Cosyn J. (2015) The current use of patient centered/reported outcomes in implant dentistry. A systematic review. Beikler T & Flemmig T.F. (2015) Economic evaluation of implant-supported prostheses. A narrative review.

Prevalence and risk factors for peri‐implant disease in Belgian adults

This study aimed to evaluate in a Belgian population the frequence of mucositis and peri-implantitis in patients with implants of at least 5 years of function. Another outcome was to access implants/patients characteristics as possible risk indicators for peri-implantitis. One hundred and three patients (38 males/65 females) with a total of 266 implants were examined. Implants had been inserted in university hospitals as well as in private clinics and the mean time of implants in function was 8.5years (±3.2). The average patients' age within the population was 62years (±13.4). General health informations were recorded as well as habits regarding smoking, maintenance visits and oral hygiene. Full mouth clinical parameters (PlI, BoP, PPD) were assessed and radiographs taken to determine the periodontal status and implants diagnosis. Prevalences of mucositis and peri-implantitis at the patient's level were respectively 31% and 37%. They were 38% and 23% at the implant's level. Subjects older than 65years (OR = 1.39) and those with active periodontitis (OR = 1.98) were prone to peri-implantitis. The association was stronger for hepatitis (OR = 2.92) and totally edentulous patients (OR = 5.56). Finally, at the implant's level, a significant correlation was found in the multi-level analyses between rough surfaces, overdentures and peri-implantitis. After 8.5years an important proportion (±60%) of implants presented biological complications. Furthermore, a positive correlation was showed between age, periodontitis, absence of teeth, rough surfaces and peri-implantitis. Consequently, patients with such characteristics should be informed before implant placement and frequently re-called after for maintenance visits.

Residual periodontal pockets are a risk indicator for peri-implantitis in patients treated for periodontitis

Does the data support the conclusion that 'the maintenance of periodontal health, rather than the previous history of periodontitis, is the critical determinant of increased risk of peri-implant disease'?

The association between selected risk indicators and severity of peri-implantitis using mixed model analyses

The aim of the study was to assess possible risk indicators for peri-implantitis at different levels of severity using multi-level analyses. One hundred and nine subjects attended the examination, 69 females and 40 males. Mean time of implants in function was 8.4 years (standard deviation 4.6) (subject level). The participants were examined clinically and radiographically. Information regarding general health and habits was gathered, with special emphasis on smoking, oral hygiene and susceptibility to periodontitis. The relation between possible risk indicators and the following features were assessed: • Detectable peri-implantitis: detectable radiographic bone loss (>0.4 mm) and inflammation • Overt peri-implantitis: radiographic peri-implant bone loss 2.0 mm and bleeding on probing /suppuration at pocket probing depth 4 mm. Multi-level statistical analyses identified location in the maxilla as risk indicator for detectable peri-implantitis. Regarding overt peri-implantitis, gender (male) and history of periodontitis were identified as risk indicators. Individuals with a history of periodontitis were prone to peri-implantitis, peri-implant bone loss ≥ 2.0 mm and overt in the present study. No association was found between smoking and peri-implant disease in the present study population.