Jan Derks

Effectiveness of Implant Therapy Analyzed in a Swedish Population: Prevalence of Peri-implantitis

Peri-implantitis is an inflammatory disease affecting soft and hard tissues surrounding dental implants. As the global number of individuals that undergo restorative therapy through dental implants increases, peri-implantitis is considered as a major and growing problem in dentistry. A randomly selected sample of 588 patients who all had received implant-supported therapy 9 y earlier was clinically and radiographically examined. Prevalence of peri-implantitis was assessed and risk indicators were identified by multilevel regression analysis. Forty-five percent of all patients presented with peri-implantitis (bleeding on probing/suppuration and bone loss >0.5 mm). Moderate/severe peri-implantitis (bleeding on probing/suppuration and bone loss >2 mm) was diagnosed in 14.5%. Patients with periodontitis and with ≥4 implants, as well as implants of certain brands and prosthetic therapy delivered by general practitioners, exhibited higher odds ratios for moderate/severe peri-implantitis. Similarly, higher odds ratios were identified for implants installed in the mandible and with crown restoration margins positioned ≤1.5 mm from the crestal bone at baseline. It is suggested that peri-implantitis is a common condition and that several patient- and implant-related factors influence the risk for moderate/severe peri-implantitis (ClinicalTrials.gov NCT01825772).

Primary prevention of peri-implantitis: managing peri-implant mucositis

AIMS Over the past decades, the placement of dental implants has become a routine procedure in the oral rehabilitation of fully and partially edentulous patients. However, the number of patients/implants affected by peri-implant diseases is increasing. As there are--in contrast to periodontitis--at present no established and predictable concepts for the treatment of peri-implantitis, primary prevention is of key importance. The management of peri-implant mucositis is considered as a preventive measure for the onset of peri-implantitis. Therefore, the remit of this working group was to assess the prevalence of peri-implant diseases, as well as risks for peri-implant mucositis and to evaluate measures for the management of peri-implant mucositis. METHODS Discussions were informed by four systematic reviews on the current epidemiology of peri-implant diseases, on potential risks contributing to the development of peri-implant mucositis, and on the effect of patient and of professionally administered measures to manage peri-implant mucositis. This consensus report is based on the outcomes of these systematic reviews and on the expert opinion of the participants. RESULTS Key findings included: (i) meta-analysis estimated a weighted mean prevalence for peri-implant mucositis of 43% (CI: 32-54%) and for peri-implantitis of 22% (CI: 14-30%); (ii) bleeding on probing is considered as key clinical measure to distinguish between peri-implant health and disease; (iii) lack of regular supportive therapy in patients with peri-implant mucositis was associated with increased risk for onset of peri-implantitis; (iv) whereas plaque accumulation has been established as aetiological factor, smoking was identified as modifiable patient-related and excess cement as local risk indicator for the development of peri-implant mucositis; (v) patient-administered mechanical plaque control (with manual or powered toothbrushes) has been shown to be an effective preventive measure; (vi) professional intervention comprising oral hygiene instructions and mechanical debridement revealed a reduction in clinical signs of inflammation; (vii) adjunctive measures (antiseptics, local and systemic antibiotics, air-abrasive devices) were not found to improve the efficacy of professionally administered plaque removal in reducing clinical signs of inflammation. CONCLUSIONS Consensus was reached on recommendations for patients with dental implants and oral health care professionals with regard to the efficacy of measures to manage peri-implant mucositis. It was particularly emphasized that implant placement and prosthetic reconstructions need to allow proper personal cleaning, diagnosis by probing and professional plaque removal.

Clinical research of peri‐implant diseases – quality of reporting, case definitions and methods to study incidence, prevalence and risk factors of peri‐implant diseases

AIM To review the quality of reporting and the methodology of clinical research on the incidence, prevalence and risk factors of peri-implant diseases. METHODS A MEDLINE search was conducted for cross-sectional, case-control and prospective longitudinal studies reporting on peri-implant diseases. To evaluate the quality of reporting of the selected studies the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) checklist was utilized. RESULTS The search provided 306 titles and abstracts, out of which 40 were selected for full-text analysis. Finally, 16 studies were included out of which five assessed prevalence and only two the incidence of peri-implant diseases. 13 articles studied risk indicators for peri-implant diseases. None of the scrutinized articles adhered fully to the STROBE criteria. The large majority of articles did not (i) clearly state the applied study design, (ii) describe any effort to address potential sources of bias, (iii) explain how missing data were addressed, (iv) perform any kind of sensitivity analysis, (v) indicate the number of participants with missing data for each variable of interest. CONCLUSION Collectively, the findings of this review indicate a need for improved reporting of epidemiological studies on peri-implant diseases.

Effectiveness of Implant Therapy Analyzed in a Swedish Population Early and Late Implant Loss

Treatment outcomes in implant dentistry have been mainly assessed as implant survival rates in small, selected patient groups of specialist or university clinical settings. This study reports on loss of dental implants assessed in a large and randomly selected patient sample. The results were aimed at representing evaluation of effectiveness of implant dentistry. Using the national data register of the Swedish Social Insurance Agency, 4,716 patients were randomly selected. All had been provided with implant-supported restorative therapy in 2003. Patient files of 2,765 patients (11,311 implants) were collected from more than 800 clinicians. Information on patients, treatment procedures, and outcomes related to the implant-supported restorative therapy was extracted from the files. In total, 596 of the 2,765 subjects, provided with 2,367 implants, attended a clinical examination 9 y after therapy. Implant loss that occurred prior to connection of the supraconstruction was scored as an early implant loss, while later occurring loss was considered late implant loss. Early implant loss occurred in 4.4% of patients (1.4% of implants), while 4.2% of the patients who were examined 9 y after therapy presented with late implant loss (2.0% of implants). Overall, 7.6% of the patients had lost at least 1 implant. Multilevel analysis revealed higher odds ratios for early implant loss among smokers and patients with an initial diagnosis of periodontitis. Implants shorter than 10 mm and representing certain brands also showed higher odds ratios for early implant loss. Implant brand also influenced late implant loss. Implant loss is not an uncommon event, and patient and implant characteristics influence outcomes (ClinicalTrials.gov NCT01825772).

Adjunctive Systemic and Local Antimicrobial Therapy in the Surgical Treatment of Peri-implantitis A Randomized Controlled Clinical Trial

The aim of the present randomized controlled clinical trial was to investigate the adjunctive effect of systemic antibiotics and the local use of chlorhexidine for implant surface decontamination in the surgical treatment of peri-implantitis. One hundred patients with severe peri-implantitis were recruited. Surgical therapy was performed with or without adjunctive systemic antibiotics or the local use of chlorhexidine for implant surface decontamination. Treatment outcomes were evaluated at 1 y. A binary logistic regression analysis was used to identify factors influencing the probability of treatment success, that is, probing pocket depth ≤5 mm, absence of bleeding/suppuration on probing, and no additional bone loss. Treatment success was obtained in 45% of all implants but was higher in implants with a nonmodified surface (79%) than those with a modified surface (34%). The local use of chlorhexidine had no overall effect on treatment outcomes. While adjunctive systemic antibiotics had no impact on treatment success at implants with a nonmodified surface, a positive effect on treatment success was observed at implants with a modified surface. The likelihood for treatment success using adjunctive systemic antibiotics in patients with implants with a modified surface, however, was low. As the effect of adjunctive systemic antibiotics depended on implant surface characteristics, recommendations for their use in the surgical treatment of peri-implantitis should be based on careful assessments of the targeted implant (ClinicalTrials.gov NCT01857804).

Peri-implantitis – onset and pattern of progression

BACKGROUND While information on the prevalence of peri-implantitis is available, data describing onset and progression of the disease are limited. MATERIAL & METHODS A 9-year follow-up examination of 596 randomly selected implant-carrying individuals identified 62 patients with moderate/severe peri-implantitis. Longitudinal assessments of peri-implant marginal bone levels were used to construct a statistical model with bone loss as the dependent variable. A multilevel growth model estimated the pattern of bone loss for each implant/patient. Onset of peri-implantitis was determined by evaluating the cumulative percentage of implants/patients presenting with estimated bone loss at each year following prosthesis delivery. RESULTS The analysis showed a non-linear, accelerating pattern of bone loss at the 105 affected implants. The onset of peri-implantitis occurred early, and 52% and 66% of implants presented with bone loss of >0.5 mm at years 2 and 3 respectively. A total of 70% and 81% of subjects presented with ≥1 implants with bone loss of >0.5 mm at years 2 and 3 respectively. CONCLUSIONS It is suggested that peri-implantitis progresses in a non-linear, accelerating pattern and that, for the majority of cases, the onset occurs within 3 years of function.

Patient‐reported outcomes of dental implant therapy in a large randomly selected sample

BACKGROUND In addition to traditional clinical parameters, the need to include patient-reported assessments into dental implant research has been emphasized. AIM The aim of this study was to evaluate patient-reported outcomes following implant-supported restorative therapy in a randomly selected patient sample. MATERIAL AND METHODS Four thousand seven hundred and sixteen patients were randomly selected from the data register of the Swedish Social Insurance Agency. A questionnaire containing 10 questions related to implant-supported restorative therapy was mailed to each of the individuals about 6 years after therapy. Associations between questionnaire data, and (i) patient-related, (ii) clinician-related and (iii) therapy-related variables were identified by multivariate analyses. RESULTS Three thousand eight hundred and twenty-seven patients (81%) responded to the questionnaire. It was demonstrated that the overall satisfaction among patients was high. Older patients presented with an overall more positive perception of the results of the therapy than younger patients and males were more frequently satisfied in terms of esthetics than females. While clinical setting did not influence results, patients treated by specialist dentists as opposed to general practitioners reported a higher frequency of esthetic satisfaction and improved chewing ability. In addition, patients who had received extensive implant-supported reconstructions, in contrast to those with small reconstructive units, reported more frequently on improved chewing ability and self-confidence but also to a larger extent on implant-related complications. CONCLUSION It is suggested that patient-perceived outcomes of implant-supported restorative therapy are related to (i) age and gender of the patient, (ii) the extent of restorative therapy and (iii) the clinician performing the treatment.

Peri-implant diseases and conditions: Consensus report of workgroup 4 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions

A classification for peri-implant diseases and conditions was presented. Focused questions on the characteristics of peri-implant health, peri-implant mucositis, peri-implantitis, and soft- and hard-tissue deficiencies were addressed. Peri-implant health is characterized by the absence of erythema, bleeding on probing, swelling, and suppuration. It is not possible to define a range of probing depths compatible with health; Peri-implant health can exist around implants with reduced bone support. The main clinical characteristic of peri-implant mucositis is bleeding on gentle probing. Erythema, swelling, and/or suppuration may also be present. An increase in probing depth is often observed in the presence of peri-implant mucositis due to swelling or decrease in probing resistance. There is strong evidence from animal and human experimental studies that plaque is the etiological factor for peri-implant mucositis. Peri-implantitis is a plaque-associated pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. Peri-implantitis sites exhibit clinical signs of inflammation, bleeding on probing, and/or suppuration, increased probing depths and/or recession of the mucosal margin in addition to radiographic bone loss. The evidence is equivocal regarding the effect of keratinized mucosa on the long-term health of the peri-implant tissue. It appears, however, that keratinized mucosa may have advantages regarding patient comfort and ease of plaque removal. Case definitions in day-to-day clinical practice and in epidemiological or disease-surveillance studies for peri-implant health, peri-implant mucositis, and peri-implantitis were introduced. The proposed case definitions should be viewed within the context that there is no generic implant and that there are numerous implant designs with different surface characteristics, surgical and loading protocols. It is recommended that the clinician obtain baseline radiographic and probing measurements following the completion of the implant-supported prosthesis.

Dental implant register: Summary and consensus statements of group 2. The 5th EAO Consensus Conference 2018

OBJECTIVES This publication reports the EAO Workshop group-2 and consensus plenary discussions and statements on a narrative review providing the background and possible facilities and importance of a dental implant register, to allow for a systematic follow-up of the clinical outcome of dental implant treatment in various clinical settings. It should be observed that the format of the review and the subsequent consensus report consciously departs from conventional consensus publications and reports. MATERIAL AND METHODS The publication was a narrative review on the presence and significance of quality registers regarding select medical conditions and procedures. The group discussed and evaluated the publication and made corrections and recommendations to the authors and agreed on the statements and recommendations described in this consensus report. RESULTS Possible registrations to be included in an implant register were discussed and agreed as a preliminary basis for further development, meaning that additional parameters be included or some be deleted. CONCLUSIONS It was agreed to bring the idea of an implant quality register, including the presented results of discussions and proposals by the group- and plenary sessions, to the EAO Board for further discussion and decision.

Response to Letter to the Editor, “Effectiveness of Implant Therapy Analyzed in a Swedish Population: Early and Late Implant Loss”

We appreciate the opportunity to respond to the letter to the editor. Adjustments of P values in multiple comparisons to decrease the risk for type I error, as suggested in the letter, lead to an increased risk for type II error. Therefore, such a strategy is discouraged in epidemiologic research with the goal of identifying potential risk indicators for disease (Rothman 1990; Bender and Lange 2001). We strongly disagree with the statement that “no formal conclusions should be drawn—or indicated.” Our publication describes effectiveness of implant therapy using data obtained from 2,765 subjects (Derks et al. 2015). The report is among the largest studies in the field. The material is unique as it represents 1) a randomly selected sample of patients, 2) a multitude of clinicians with varying experience, and 3) different implant systems. Existing evidence on risk factors/indicators for implant complications is mainly based on observational research in descriptive studies (Tonetti et al. 2012). While randomized clinical trials are ultimately required for clinical recommendations, information on effectiveness of a therapy cannot be retrieved from such studies.