Construction of a diagnostic model based on random forest and artificial neural network for peri-implantitis

OBJECTIVES

This study aimed to reveal critical genes regulating peri-implantitis during its development and construct a diagnostic model by using random forest (RF) and artificial neural network (ANN).

METHODS

GSE-33774, GSE106090, and GSE57631 datasets were obtained from the GEO database. The GSE33774 and GSE106090 datasets were analyzed for differential expression and functional enrichment. The protein-protein interaction networks (PPI) and RF screened vital genes. A diagnostic model for peri-implantitis was established using ANN and validated on the GSE33774 and GSE57631 datasets. A transcription factor-gene interaction network and a transcription factor-micro-RNA (miRNA) regulatory network were also established.

RESULTS

A total of 124 differentially expressed genes (DEGs) involved in the regulation of peri-implantitis were screened. Enrichment analysis showed that DEGs were mainly associated with immune receptor activity and cytokine receptor activity and were mainly involved in processes such as leukocyte and neutrophil migration. The PPI and RF screened six essential genes, namely, CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8. The receiver operating characteristic curve (ROC) indicated that the ANN model had an excellent diagnostic performance. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 may be a key miRNA.

CONCLUSIONS

The diagnostic model of peri-implantitis constructed by RF and ANN has high confidence, and CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8 are potential diagnostic markers. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 plays a vital role as a critical miRNA.

A longitudinal analysis of the impact of nonsurgical and surgical treatment of peri-implantitis upon clinical parameters and implant stability quotient values. A 2-3-year follow-up

OBJECTIVES

In this study, the aim was to investigate the medium- to long-term impact of peri-implantitis treatment upon clinical parameters and implant stability quotient values and to ascertain if magnetic resonance frequency analysis can be used as a diagnostic tool to demonstrate postoperative healing following treatment of peri-implantitis.

MATERIALS AND METHODS

A total of n = 26 patients (n = 86 implants) diagnosed with peri-implantitis were recruited for this prospective cohort study and four different treatment modalities were used. Baseline measurements of a number of clinical parameters as well as implant stability measurements in the form of ISQ were recorded. These measurements were repeated at 6, 12, and 24-36 months following treatment. Analysis of variance was performed for all implants treated as well as separately for each treatment modality. A regression model was also used to determine factors affecting ISQ measurements over time.

RESULTS

Treatment of peri-implantitis resulted in significant improvements of both average PPDs and BOP (p < .0001 and p < .01). ISQ values marginally improved initially for all treatment modalities, but improvement was only maintained for 2-3 years in treatment modalities I (+1.28), III (+1.49), and IV (+2.92). There was a statistically significant negative linear correlation between average PPD and the ISQ values recorded both at baseline (r = -.618, p < 0.0001) and at 2/3 years (r = -.604, p < 0.0001).

CONCLUSION

Over the 2-3-year follow-up period, all four treatment modalities led to improved clinical and radiographic peri-implant parameters but implant stability posttreatment, as indicated by the fact that the recorded ISQ scores remained stable. As a result, use of MRFA as an adjunct to the traditionally used periodontal and radiographic tools for the evaluation of postoperative implant stability following the treatment of peri-implant disease cannot be recommended.

Clinical Dilemmas in the Differential Diagnosis of Peri-implantitis: Case Presentation and Literature Review

Advancements in the field of implantology have made dental implants a mainstay treatment for both fully and partially edentulous patients. As a result, practitioners need to be able to identify clinical signs of peri-implant disease in its early stages and provide patients with reliable treatment options. The objective of this article is to provide a differential diagnosis of peri-implant lesions, outlining the clinical, radiographic, and histopathologic features of similar benign and malignant conditions. Additionally, two case studies are presented that showcase lesions that mimic peri-implantitis, providing practitioners with practical examples of how to apply the discussed features in a clinical setting. Lesions described in the differential diagnosis include physiologic bone loss, implant fracture, loosened abutments, pyogenic granuloma, peripheral giant cell granuloma, peripheral ossifying fibroma, squamous cell carcinoma, and metastasis extending to the oral cavity.

Spectroscopic insights into peri-implant mucositis and peri-implantitis: unveiling peri-implant crevicular fluid profiles using surface enhanced Raman scattering

The precise identification and differentiation of peri-implant diseases, without the need for intrusive procedures, is crucial for the successful clinical treatment and overall durability of dental implants. This work introduces a novel approach that combines surface-enhanced Raman scattering (SERS) spectroscopy with advanced chemometrics to analyse peri-implant crevicular fluid (PICF) samples. The primary purpose is to offer an unbiased evaluation of implant health. A detailed investigation was performed on PICF samples obtained from a cohort of patients exhibiting different levels of peri-implant health, including those with healthy implants, implants impacted by peri-implantitis, and implants with peri-implant mucositis. The obtained SERS spectra were analysed using canonical-powered partial least squares (CPPLS) to identify unique chemical characteristics associated with each inflammatory state. Significantly, our research findings unveil the presence of a common inflammatory SERS spectral pattern in cases of peri-implantitis and peri-implant mucositis. Furthermore, the SERS-based scores obtained from CPPLS were combined with established clinical scores and subjected to a linear discriminant analysis (LDA) classifier. Repeated double cross-validation was used to validate the method's capacity to discriminate different implant conditions. The integrated approach showcased high sensitivity and specificity and an overall balanced accuracy of 92%, demonstrating its potential to serve as a non-invasive diagnostic tool for real-time implant monitoring and early detection of inflammatory conditions.

Diagnostic value of VEGF in peri-implantitis and its correlation with titanium particles: A controlled clinical study

OBJECTIVES

VEGF is prototypic marker of neovascularization, repeatedly proposed as intrinsic characteristic of peri-implantitis. This study aimed to assess pattern of VEGF in peri-implantitis, its correlation with titanium particles (TPs) and capacity as respective biomarker.

MATERIAL AND METHODS

Pathological specificity of VEGF was assessed in peri-implant granulations using immunohistochemistry, periodontal granulations represented Ti-free positive controls. VEGF was correlated to TPs, identified using scanning electron microscopy coupled with dispersive x-ray spectrometry. Diagnostic accuracy, sensitivity and specificity of VEGF were estimated in PICF specimens from peri-implantitis, peri-implant mucositis (PIM) and healthy peri-implant tissues (HI) using machine learning algorithms.

RESULTS

Peri-implantitis exhibited rich neovascular network with expressed density in contact zones toward neutrophil infiltrates without specific pattern variations around TPs, identified in all peri-implantitis specimens (mean particle size 8.9 ± 24.8 µm2; Ti-mass (%) 0.380 ± 0.163). VEGF was significantly more expressed in peri-implantitis (47,065 ± 24.2) compared to periodontitis (31,14 ± 9.15), and positively correlated with its soluble concentrations in PICF (p = 0.01). VEGF was positively correlated to all clinical endpoints and significantly increased in peri-implantitis compared to both PIM and HI, but despite high specificity (96%), its overall diagnostic capacity was average. Two patient clusters were identified in peri-implantitis, one with 8-fold higher VEGF values compared to HI, and second with lower values comparable to PIM.

SIGNIFICANCE

VEGF accurately reflects neovascularization in peri-implantitis that was expressed in contact zones toward implant surface without specific histopathological patter variation around TPs. VEGF answered requests for biomarker of peri-implantitis but further research is necessary to decrypt its exact underlying cause.

Diagnosis and Treatment of Periimplant Mucositis and Periimplantitis: An Overview and Related Controversial Issues

Periimplant mucositis and periimplantitis are common complications of dental implant. This article provides a comprehensive overview of the 2017 World Workshop's new definition, clinical and radiographic presentation, pathogenesis, risk factors, and classification of periimplant diseases. Also, the authors discuss various types of instruments, materials, and techniques commonly used for treatment of nonsurgical and surgical periimplantitis. Lastly, the authors include some controversial topics surrounding this subject.

Knowledge and attitude of dental students regarding etiology, diagnosis, and treatment of peri-implantitis

OBJECTIVE

The objective of this study was to assess the level of knowledge and attitude of dental students about the etiology, diagnosis, and management of peri-implantitis.

METHODS

An online cross-sectional study that targeted senior undergraduate dental students at the College of Dentistry was conducted. A closed-ended survey consisting of 28 questions was designed. Three sections were created: 1) participants' characteristics; 2) Knowledge of peri-implantitis etiology, risk factors, diagnosis, and complications; 3) The use of antibiotics in peri-implantitis, diagnosis, and treatment methods. SPSS version 22 (IBM Corp.) was used for data analysis. Counts and percentages were calculated for correct answers in each section.

RESULTS

A total of 267 dental students responded to the questionnaire. The majority of the participants (81.6%) were knowledgeable about peri-implantitis being an inflammatory reaction, and a lesser percentage (77.9%) knew that bacterial plaque is an etiologic factor for peri-implant diseases. 82.0% of the participants identified smoking as a risk factor, followed by periodontitis (80.5%). Regarding implant complications, 57.3% of the participants considered implant mobility as a definitive indication for implant removal. More than half of the participants reported using crater-like bone defects surrounding implants to diagnose peri-implantitis. The most commonly used antibiotic was amoxicillin (34.1%), followed by amoxicillin combined with metronidazole (26.9%).

CONCLUSION

Most participants had a basic understanding of the etiology and risk factors of peri-implantitis. On the other hand, more courses addressing peri-implantitis diagnosis are needed.

Peri-implantitis Diagnosis and Prognosis Using Biomarkers: A Systematic Literature Review

PURPOSE

To summarize the latest scientific literature regarding the concentrations of biomarkers in saliva and peri-implant crevicular fluid (PICF) of healthy implant (HI) patients and patients with peri-implant mucositis (PIM) and peri-implantitis (PI).

MATERIALS AND METHODS

The literature review was performed according to PRISMA guidelines. The databases used were PubMed MEDLINE, ScienceDirect, and Cochrane Library. A combination of keywords was used, and selection criteria were applied. Selected articles were published between February 1, 2017, and February 1, 2022, written in English, conducted in humans, and examined the levels of saliva and PICF biomarkers in PI patients and compared them to HI/PIM patients.

RESULTS

A total of 16 publications were selected, involving a total of 1,117 patients with 1,346 implants. Qualitative analysis revealed 49 different biomarkers, the levels of which were compared between groups. After evaluating the most frequently studied biomarkers, significantly higher values of IL-1β, RANKL, sRANKL, IL-6, TNF-α, TNFSF12, MMP2, and MMP8 levels were observed in the PI group than in the HI group.

CONCLUSIONS

Of all 49 biomarkers evaluated, IL-1β and RANKL have potentially the highest diagnostic significance in the assessment of peri-implant inflammatory conditions, as differences were observed between all three groups (HI < PIM < PI), but data from current publications were not fully sufficient to provide strong evidence.

[Interpretation of the European Federation of Periodontology S3 level clinical practice guideline for prevention and treatment of peri-implant diseases]

The S3 level clinical practice guideline for the prevention and treatment of peri-implant diseases, developed by the European Federation of Periodontology, was published in June, 2023 (DOI: 10.1111/jcpe.13823), which culminated in the recommendations for implementation of various different interventions before, during and after implant placement/loading. Aim of the present article is to summarize and interpret the key points of this guideline and help clinicians understand this guideline better, in order to standardize the prevention and treatment of peri-implant diseases.

Dentists' perceptions and usability testing of the implant disease risk assessment IDRA, a tool for preventing peri‑implant disease: A qualitative study

INTRODUCTION

we aimed to explore dentists' perceptions toward the implementation of a dental informatics risk assessment tool which estimates the risk for a patient to develop peri‑implantitis.

MATERIALS AND METHODS

the Implant Disease Risk Assessment Tool (IDRA) was presented to a convenience sample of seven dentists working in a university clinic, whom were asked to use IDRA with the information of three clinical cases whilst thinking aloud and then fill the System Usability Scale (SUS). A semi-structured interview technique was used with audio record to allow free expression of participants' perceptions related to the IDRA. The interviews information was categorized and analyzed by the authors.

RESULTS

to our knowledge, this is the first study conducted to develop a qualitative usability test of IDRA, evaluating the effectiveness, efficiency, and users' satisfaction. There were more variations in responses the greater the degree of complexity of the clinical case. Generally, the participants classified the tool as good, getting usability values of 77,2 (SD 19,8) and learnability 73,2 (SD 24,5).

CONCLUSION

four additional factors should be considered to improve IDRA tool: 1) considering the relation between contour angle and peri-implant tissue height; 2) automatic periodontal classification in the IDRA tool after completing the periodontogram in the clinical software; 3) presentation of a flowchart to assist therapeutic decisions alongside the final score defined by the IDRA tool; 4) integrating of precision tests such as Implantsafe® DR… (dentognostics gmbh, Jena) and Oralyzer®(dentognostics gmbh, Jena).

CLINICAL SIGNIFICANCE

etiology and pathogenesis of peri‑implant diseases is multifactorial. These tools must follow a natural integration to be easily applied in a clinical setting. It is important to study their usability from the clinicians' point of view, evaluating the effectiveness, efficiency, and users' satisfaction.

aMMP-8 point-of-care - diagnostic methods and treatment modalities in periodontitis and peri-implantitis

INTRODUCTION

When collected in a standardized fashion, oral fluid analysis can refine the diagnosis of periodontal and peri-implant disease. In practice, dental professionals can perform active matrix metalloproteinase (aMMP-8) analysis chairside.

AREAS COVERED

Periodontal tissues are mainly made up of type I collagen, and collagen breakdown is one of the main events in periodontal and peri-implantitis destructive lesions. In addition to traditional measurements, their diagnosis can be refined with tests utilizing oral fluids. The active matrix metalloproteinase-8 (aMMP-8) is possible to be determined from the gingival crevicular fluid (GCF), peri-implant sulcus fluid (PISF), and other oral fluids such as mouth rinse and saliva. We also investigated the applicability of aMMP-8 chair-side test kits in the evaluation of oral health benefits of different adjunctive host-modulating periodontal therapies including fermented lingonberry mouthwash (FLJ) and antibacterial photodynamic therapy (aPDT).

EXPERT OPINION

The aMMP-8 levels can more reliably detect early activation of periodontal and peri-implant disease as compared to traditional diagnostic methods that assess the experienced health status or past disease, rather than the present or future pathology. Novel therapies like, fermented lingonberry juice as a mouthrinse or aPDT, are potential host-modulating adjunctive treatments to reduce the signs of oral inflammation and infection.

Biomarkers from Peri-Implant Crevicular Fluid (PICF) as Predictors of Peri-Implant Bone Loss: A Systematic Review

The aim of the present systematic review is to summarize current knowledge regarding the analysis of biomarkers extracted from peri-implant crevicular fluid (PICF) as predictors of peri-implant bone loss (BL). An electronic search was conducted on three databases, PubMed/MEDLINE, Cochrane Library, and Google Scholar, to find clinical trials published until 1 December 2022 suitable to answer the following focused question: in patients with dental implants, are biomarkers harvested from PICF predictive of peri-implant BL? The initial search yielded a total of 158 entries. After a full-text review and application of the eligibility criteria, the final selection consisted of nine articles. The risk of bias in included studies was assessed using the Joanna Briggs Institute Critical Appraisal tools (JBI). According to the present systematic review, some inflammatory biomarkers harvested from PICF (collagenase-2, collagenase-3, ALP, EA, gelatinase b, NTx, procalcitonin, IL-1β, and several miRNAs) seem to be correlated with peri-implant BL and may assist in the early diagnosis of pathological BL, that characterizes peri-implantitis. MiRNA expression demonstrated a predictive potential of peri-implant BL that could be useful for host-targeted preventive and therapeutic purposes. PICF sampling may represent a promising, noninvasive, and repeatable form of liquid biopsy in implant dentistry.

Underdiagnosis in Background of Emerging Public Health Challenges Related to Peri-Implant Diseases: An Interventional Split-Mouth Study

Peri-implant diseases are an emerging public health problem, and it's considered that limitations of standard diagnostics play the role herein. The study objective was the estimation of pathological bone resorption at clinical and biological level in patients with peri-implant mucositis (PIM) and peri-implantitis (PI) before and 6 months after standard treatment and to compare them with healthy controls (HC). The split-mouth interventional study included 60 patients affected with PIM or PI. Patients that also presented at least one more HC were enrolled in the study and underwent standard non-surgical and surgical treatment, respectively. Standard clinical parameters and soluble levels of RANKL were measured in peri-implant crevicular fluid baseline and 6 months following treatment. Clinical parameters and RANKL significantly decreased following treatment in PIM and PI. However, bleeding on probing and probing depth remained significantly increased when compared to HC. RANKL answered requests for biomarker of peri-implant diseases, its baseline levels were significantly increased in PIM and PI, they decreased following treatment and reached HC in peri-implantitis, while in PIM RANKL remained significantly increased. Presence of pathological bone resorption in patients lacked its clinical signs, and respective persistence following treatment suggest the need for biomarker-supported diagnosis for timely diagnosis of peri-implantitis and appropriate orientation of respective management strategies.

Peri-implant crevicular fluid SIRT1 levels decrease in patients with peri-implant inflammatory: A prospective observational study

BACKGROUND

A dental Implant is a prosthetic device made of alloplastic materials implanted into the bone to provide retention and support for a dental prosthesis. Sirtuin1 (SIRT1) molecule, a nicotinamide adenine dinucleotide (NAD)-dependent histone deacetylase, regulates a variety of physiological and pathological processes, including oxidative stress, metabolism, cell proliferation, cell differentiation, inflammatory, and apoptosis. We explored whether the expression of SIRT1 correlates in patients receiving implants with peri-implant mucositis (PIM) and peri-implantitis (PI) in comparison to patients with healthy peri-implant area (PIH).

METHODS

A number of 198 patients with dentition defects were enrolled in the study after their implants were functional for at least 6 months. All 198 subjects were divided into 3 groups: 1) control patients with PIH healthy implants; 2) patients with PIM mucositis; and 3) patients with PI implantitis. To distinguish these three groups, peri-implant crevicular fluid (PICF) was collected by inserting a sterile paper strip into the gap around the implant and the levels of SIRT1 and cytokines were measured by the enzyme linked immunosorbent assay (ELISA). Demographic and clinical data included age, sex, Body Mass Index (BMI), probing depth (PD), plaque index (PLI), bleeding on probing (BOP), oral health impact profile (OHIP-14), history of periodontitis and the use time of implants.

RESULTS

The PD, PLI, OHIP-14 evaluation scores in patients with periodontitis of PIM mucositis and PI implantitis were all significantly higher than in patients with PIH healthy implants. Overall, the SIRT1 levels in PICF of the PIM and PI patients were significantly lower than of the PIH patients. In comparison with PIM patients, SIRT1 levels of the PI patients were remarkably lower than the PIH patients. Pearson's analysis showed that SIRT1 levels were negatively correlated with levels of interleukin (IL)-6, C-reactive protein (CRP) and IL-1β in patients with PIM and PI. We suggest that SIRT1 levels could serve as a potential diagnostic biomarker of PI or PIM. The PICF levels of SIRT1, CRP, IL-6, IL-1β and the history of periodontitis were the risk factors for patients with peri-implant inflammatory process.

CONCLUSION

The measurement of SIRT1 expression in PICF may serve as a biomarker for the ongoing inflammatory process in patients with dental implants. The low SIRT1 levels correlated with PI implantitis and PIM mucositis as well as the elevated levels of pro-inflammatory cytokines (CRP, IL-6 and IL-1β).

A Revised Peri-implantitis Classification Scheme: Adding Three-Dimensional Considerations to Facilitate Prognosis and Treatment Planning

Historically, diagnosing peri-implantitis is done based on whether the disease is present, evaluated using the arbitrary thresholds of probing depths and bone loss. Using this approach as a tool to ascertain meaningful information regarding prevalence and treatment is limited. Efforts have been made to improve upon this, but to date, only one of these classifications has provided a simple method to communicate disease severity based on the amount of bone loss. A modified version of this simplified classification is proposed here, including information regarding the implant position, as emerging information suggests that this is a crucial factor in the etiology and prognosis of peri-implantitis. This enhancement to the classification better serves both researchers and clinicians in their discussion about peri-implantitis and helps to determine and recommend the most effective methods of management.

[Diagnosis, etiology, prevention and treatment in retrograde peri-implantitis]

Retrograde peri-implantitis (RPI), a kind of rare biological complication in implant-supported prosthetic rehabilitation, has been reported more frequently in recent years. RPI is defined as the periapical lesion that occurs following implant placement while the coronal part of the implant achieves normal osseointegration. Due to the possibilities of asymptomatic clinical scenarios, RPI can easily be ignored if routine radiographic examination is absent postoperatively, which may postpone treatment and affect long-term outcome. The common cause is infection originating from the periapical lesion of the neighboring teeth, the residual bacteria at the implant site, the contaminated implant apex and etc. Treatment methods rely on the infection source and severity of defect. This article discusses the diagnosis, classification, etiology, and pathology as well as prevention and treatment of RPI in order to provide evidence for clinical decisions in the future.

Peri-implant squamous cell carcinoma mimicking peri-implantitis: a case report

Peri-implant oral lesions, benign or malignant, may be misdiagnosed as peri-implantitis. Squamous cell carcinoma is the most common cancer reported around dental implants. Malignant peri-implant lesions are life-threatening, and their resemblance to peri-implantitis, especially in their early stage, necessitates a precise differential diagnosis. This report presents a case of a 55-year-old woman with a peri-implant squamous cell carcinoma mimicking peri-implantitis.

[The Dutch guidelines for prevention and treatment of periodontal and peri-implant diseases]

The Dutch guideline 'Diagnosis, prevention and treatment of peri-implant infections' provides recommendations for diagnosis, treatment, and aftercare of patients with implants. Prevention and timely treatment of complications after implantation requires a structured maintenance programme. At each follow-up appointment, pocket depth and bleeding on probing around the implants should be checked and these parameters should be recorded at least once a year. X-rays are needed to monitor the peri-implant marginal bone level and to diagnose approximal bone loss. Peri-implant diseases may occur in two forms: peri-implant mucositis and peri-implantitis. An important part of the Dutch guideline 'Periodontal screening, diagnosis and treatment in the general practice' is the Periodic Periodontal Screening (PPS). Initial periodontal treatment is the first major step to eliminate infections. The end goal of periodontal treatment is a clean, healthy mouth with shallow (≤ 5 mm), non-bleeding pockets and a functional dentition with acceptable aesthetics.

Significance of probing for monitoring peri-implant diseases

Peri-implant diseases at implant sites represent the most considerable concern for many dental clinicians nowadays due to their detrimental effect on implant longevity. Preventive measures include patient education and motivation, supportive peri-implant therapy and routine assessment of the hard and soft tissues. Nevertheless, the reliability of clinical parameters to monitor peri-implant conditions is subject to debate. As such, the primary purpose of the present review was to gain further insight into the diagnostic accuracy of probing as a clinical tool to monitor dental implants and assist clinicians in preventing peri-implant diseases. Studies have recommended periodic probing to monitor the condition of the peri-implant tissues. Increased probing pocket depth, profuse bleeding on probing and suppuration at implants are clinical signs that have been associated with peri-implantitis; thus, if these clinical parameters are present, radiographic assessment is encouraged to make a definitive diagnosis considering potential inaccuracies related to local and/or systemic factors identified in the present review.

Identification of a Predictive Decision Model Using Different Data Mining Algorithms for Diagnosing Peri-implant Health and Disease: A Cross-Sectional Study

PURPOSE

The aim of this study was to determine a predictive decision model for peri-implant health and disease and to reveal the highest accuracy of prediction using three different data mining methods.

MATERIALS AND METHODS

This cross-sectional study included a total of 216 patients with 542 dental implants from the Periodontology Department of Gazi University. The implants were classified into peri-implant health, peri-implant mucositis, and peri-implantitis groups based on established clinical and radiographic assessments. Prediction models were created using clinical variables in combination with possible risk factors for peri-implant diseases. Different data mining methods (decision-tree [DT]; J48), logistic regression, and artificial neural network (multilayer perceptron [MLP]) were compared to yield a better predictive decision model based on predictor variables with the highest potential of effect.

RESULTS

The prevalence of peri-implant mucositis and peri-implantitis among the participants of the specialist referral periodontal practice of the university was 36.1% (95% CI: 29.7 to 42.5) and 34.7% (95% CI: 28.4 to 41.0) at the patient level, respectively. The J48 method revealed a higher prediction of peri-implant health and disease with an accuracy of 0.871 compared with the logistic regression and MLP methods (0.832 and 0.852, respectively) for the present data set. In this specific patient population, the J48 model revealed the top-level node as "bleeding on probing (BOP)." "Maintenance therapy" and "medication use" were noted as powerful predictors in the next split-levels.

CONCLUSION

The J48 model presented an acceptable predictive accuracy of peri-implant health and disease. The model revealed BOP as a major predictive clinical parameter when evaluated with possible risk factors for this patient population.

Peri-implant diseases: Current understanding and management

PURPOSE

To provide an up to date, contemporary and concise evidence-based review of peri-implant diseases and conditions and discuss the current therapeutic approaches to managing these diseases.

MATERIALS AND METHODS

A literature review was conducted focusing on peri-implant health, peri-implant mucositis and peri-implantitis, as described according to the 2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions.

RESULTS AND CONCLUSIONS

Peri-implant health is described when there are no clinical signs of inflammation, and when no further bone loss after physiological remodelling or increase in probing depth can be observed. Peri-implant mucositis is a reversible inflammatory lesion that affects the soft tissues surrounding a dental implant in the absence of radiographic bone loss, whereas peri-implantitis is an irreversible pathological condition affecting the hard and soft tissues around an osseointegrated dental implant. Clinical diagnosis of peri-implant disease is in some ways similar to that of periodontitis, but their prevalence varies significantly due to many confounding variables. Different treatment modalities have been proposed and tested in the literature; as yet, however, no standard treatment protocol has been proven superior or completely effective. In future research, well-designed studies are required to assess treatment responses and evaluate additional approaches that may lead to improved outcomes.

COMPARATIVE ASSESSMENT OF THE STATUS OF PERI-IMPLANT AND PARODONTAL TISSUES

One of the controversial issues of modern dentistry is the assessment of how parodontitis arises or aggravates in the area of own teeth the severity of its course after installing orthopedic structures with support on dental implants affects the state of peri-implant tissues. Using clinical, R-genological, molecular genetic methods of research, to give a comparative assessment of the condition of parodontal tissues of own teeth and peri-implant tissues in patients who have been using fixed orthopedic constructions with support on dental implants for the treatment of partial secondary adentia for more than 5 years. To achieve this goal, we formed two groups of patients. Group 1 consisted of 34 patients (19 female and 15 male) who did not have secondary biological complications of dental implantation. The average age of patients in this group was (m. 61.3±7.8 years, f. 58.4±8.1 years) the average service life of orthopedic structures with support on dental implants was 8.3±2.3 years. The 2nd group consisted of 27 patients (15 f., 12 m.) who, on the basis of a clinical examination, R-gene examination, were diagnosed with: peri-implantitis in the area of one or more implants serving as a support for a fixed orthopedic structure. The average age of patients in this group was (m. 63±8.2 years, F 59.6±7.7 years). The average service life of an orthopedic construction was 8.8±2.5 years. In a comparative analysis of the species composition of microorganisms in the tissues of pathological parodontal pockets and peri-implant sulcus, the quantitative and species composition of microorganisms is identical in 75% of the examined patients and is individual for each patient. Based on a clinical examination, analysis of panoramic R-graphs data, parodontal diagnosis was made to patients of the 1st and 2nd groups. Based on a comparative assessment of the status of parodontal peri-implant tissues, their microbial contamination, in patients who successfully used fixed orthopedic constructions supported by dental implants to replace partial dentition defects for more than 5 years, it was found that the resistance of microbial invasion of peri-implant tissues is higher than the parodontal tissues of own teeth.

A Clinical Approach to Treatment of Retrograde Peri-Implantitis

Retrograde peri-implantitis (RPI) is a primary microbial inflammatory condition that affects only the apical portion of an osseointegrated implant, which retains normal bone-to-implant contact in its coronal portion. Currently, no uniformly accepted definition or classification exists for RPI. This article reviews the etiopathological mechanisms, diagnostic pattern, and current treatment modalities for this type of periapical implant bone loss. The prevalence of RPI is reported to be relatively low, and along with a lack of an accepted classification system there is no widely accepted treatment algorithm. Therapeutic options include antibiotics, open-flap implant debridement, and apical resection eventually including apicoectomy of endodontically affected adjacent teeth, with or without bone grafting or removal of the affected implant. Implants with RPI usually remain osseointegrated. A diagnostic approach is proposed.

A Clinical Approach to Treatment of Retrograde Peri-Implantitis

Retrograde peri-implantitis (RPI) is a primary microbial inflammatory condition that affects only the apical portion of an osseointegrated implant, which retains normal bone-to-implant contact in its coronal portion. Currently, no uniformly accepted definition or classification exists for RPI. This article reviews the etiopathological mechanisms, diagnostic pattern, and current treatment modalities for this type of periapical implant bone loss. The prevalence of RPI is reported to be relatively low, and along with a lack of an accepted classification system there is no widely accepted treatment algorithm. Therapeutic options include antibiotics, open-flap implant debridement, and apical resection eventually including apicoectomy of endodontically affected adjacent teeth, with or without bone grafting or removal of the affected implant. Implants with RPI usually remain osseointegrated. A diagnostic approach is proposed to establish the staging of the lesion and determine the best treatment option accordingly. When there is no loss of implant stability the most adequate treatment in the acute and chronic stage is apical resection of the implant with regeneration of the bone defect. If there is implant mobility, extraction of the implant is necessary.

MiR-4484 Acts as a Potential Saliva Biomarker for Early Detection of Peri-implantitis

PURPOSE

Peri-implantitis, a potentially progressive disease that occurs in patients with dental implants, is more aggressive than periodontal lesions, which makes the prevention of peri-implantitis an important priority. Due to problems in the early detection of peri-implantitis, there is an urgent need for discovering novel biologic molecules with the ability of early diagnosis. The goal of this study was to profile the microRNA content of saliva samples collected from patients with titanium-aluminum-vanadium alloy dental implants who experienced peri-implantitis and to find potential diagnostic markers for detection of this disease.

MATERIALS AND METHODS

The microRNA expression profiles of eight saliva samples (four collected from patients with peri-implantitis, four collected from patients who have successful implants) were investigated, and the deregulation of select microRNAs was further confirmed using quantitative polymerase chain reaction.

RESULTS

The expressions of 179 microRNAs were found as deregulated in the saliva of peri-implantitis patients in comparison to controls. Then, downregulation of miR-4484 was confirmed in the saliva of peri-implantitis patients in a larger validation cohort. Also, 40% of non-peri-implantitis patients and 78% of peri-implantitis patients had significantly decreased miR-4484 expression in saliva samples collected after 4 to 6 months subsequent to implant placement compared with samples collected before implant placement.

CONCLUSION

Considering these findings, microRNA content of saliva might be proposed as a plausible source for the early diagnosis of peri-implantitis, where miR-4484 might serve as an encouraging early diagnostic biomarker.

Levels of procalcitonin in saliva and peri-implant crevicular fluid in patients with peri-implant diseases and health

OBJECTIVE

To evaluate the levels of procalcitonin in saliva and peri-implant crevicular fluid (PICF) among healthy and peri-implant disease patients and correlate these levels with clinical and radiographic peri-implant parameters.

DESIGN

Three groups of 20 participants each [Group-1: healthy, Group-2: peri-implant mucositis, and Group-3: peri-implantitis] were selected. Peri-implant plaque index, bleeding on probing, probing depth and crestal bone loss was assessed. PICF and saliva samples were evaluated for procalcitonin levels and analyzed using enzyme-linked immunosorbent assay. Kruskal-Wallis test was performed for comparisons among the study groups. Multiple comparisons were considered for Post hoc two-group comparisons using Bonferroni-corrections. The Spearman rank correlation coefficient analysis was used to analyze the correlation between procalcitonin levels of both fluids and clinical peri-implant parameters.

RESULTS

Group-3 demonstrated significantly higher values for peri-implant plaque index, bleeding on probing, probing depth, and crestal bone loss as compared to Group-1 and Group-2. Participants of both Group-2 and Group-3 reported significantly increased procalcitonin levels in saliva and PICF in comparison to Group-1. Significant positive correlations were found between PICF procalcitonin levels and bleeding on probing, probing depth, and crestal bone loss in Group-3 and significant positive correlation was found between PICF and bleeding on probing in Group-2. For salivary procalcitonin levels, a significant positive correlation was observed between procalcitonin and bleeding on probing in Group-3.

CONCLUSIONS

The outcome of this study suggests that procalcitonin might play a role in peri-implant inflammation, and higher procalcitonin levels is suggestive of a probable surrogate biomarker for peri-implant diseases.

Salivary Biomarkers and Their Application in the Diagnosis and Monitoring of the Most Common Oral Pathologies

Saliva is a highly versatile biological fluid that is easy to gather in a non-invasive manner—and the results of its analysis complement clinical and histopathological findings in the diagnosis of multiple diseases. The objective of this review was to offer an update on the contribution of salivary biomarkers to the diagnosis and prognosis of diseases of the oral cavity, including oral lichen planus, periodontitis, Sjögren’s syndrome, oral leukoplakia, peri-implantitis, and medication-related osteonecrosis of the jaw. Salivary biomarkers such as interleukins, growth factors, enzymes, and other biomolecules have proven useful in the diagnosis and follow-up of these diseases, facilitating the early evaluation of malignization risk and the monitoring of disease progression and response to treatment. However, further studies are required to identify new biomarkers and verify their reported role in the diagnosis and/or prognosis of oral diseases.

Prevalence of Peri-implant Disease According to Periodontal Probing Depth and Bleeding on Probing: A Systematic Review and Meta-Analysis

PURPOSE

To compare changes in the prevalence of peri-implantitis when the unit of analysis is the subject and when the unit of analysis is the implant, by means of meta-analysis with subgroup and sensitivity analyses, according to the case definition and cutoffs. Periodontal probing depth (PPD) and bleeding on probing (BOP) were considered the primary variables.

MATERIALS AND METHODS

Electronic and manual searches of observational studies of implants with loading of more than 6 months were conducted. The quality of the studies was evaluated, and finally, a description (qualitative analysis) and a meta-analysis (quantitative analysis) of the available studies were performed.

RESULTS

Fifty-five studies were included in this systematic review, 32 of which met the criteria for evaluation of disease based on PPD and BOP. A total of 2,734 subjects and 7,849 implants were evaluated. The prevalence of peri-implantitis, defined by PPD and BOP, was 17% when the unit of analysis was the subject, and 11% when it was the implant. If the clinical criterion was PPD ≥ 4 mm, the prevalence by subject was 34% and by implant 11%. If PPD was ≥ 5 mm, the prevalence by subject was 12% and by implant 10%. Finally, if the clinical criterion was PPD ≥ 6 mm, the prevalence by subject was 18% and by implant 10%.

CONCLUSION

The prevalence of peri-implantitis is influenced by the criteria used for the case definition, and the true prevalence may currently be incorrectly estimated.

Differential expressions of biomarkers in gingival crevicular fluid of Han and Uygur populations with peri-implantitis

This study aims to investigate and compare the biomarkers in the gingival crevicular fluid between the Han and Uygur subjects with healthy implants and peri-implantitis.Totally 80 subjects were divided into the H-case (Han patients with peri-implantitis), U-case (Uygur patients with peri-implantitis), H-control (Han subjects with healthy implants), and U-control (Uygur subjects with healthy implants) groups. Cytokine levels in the gingival crevicular fluid were detected, and the dominant bacteria species were analyzed.The matrix metalloproteinase (MMP)-13 level in the gingival crevicular fluid in the U-control group was significantly higher than the H-control group, whereas the C-reactive protein level in the H-control group was significantly higher than in the U-control group. No significant difference was observed in the dominant subgingival bacteria species between the H- and U-control groups. The levels of interleukin (IL)-1β and MMP-8 were significantly higher in the H-case group than the U-case group, whereas the IL-17A level in the U-case group was significantly higher. The shared dominant subgingival bacteria species of the case groups mainly included Prevotella, clostridium, Porphyromonas, treponema, Streptococcus, neisseria, and hemophilus. Moreover, Acinetobacter, Micrococcus, and Moraxella were found to be the specific dominant subgingival bacteria species for the U-case group. In addition, compared with the H-case group, the IL-1β levels were negatively correlated with Acinetobacter, Micrococcus, and Moraxella in the U-case group.Han and Uygur populations with healthy implants and peri-implantitis have differentially expressed cytokines in the gingival crevicular fluid. Moreover, dominant subgingival bacteria species differ between the Han and Uygur populations with peri-implantitis.

Key Factors in Prevention of Peri-implant Diseases

Prevention and treatment of peri-implant diseases have become a key element in modern implant dentistry. The long-term success of implantsupported restorations is not only dependent on the quality and precision of modern implant systems, but on the efficacy of preventive measures for thelong-term maintenance of peri-implant tissues.

Five Things to Know About Peri-Implant Mucositis and Peri-Implantitis

This brief manuscript is part of an educational evidence-based series intending to inform clinicians on most recent clinical findings. This article addresses five frequent questions on peri-implant mucositis and peri-implantitis while considering its epidemiology, diagnosis, etiology and management.

Guidelines for the diagnosis and treatment of peri-implant diseases

Although some risk factors of peri-implant disease are well defined, the lack of efficient and predictable approaches to treat peri-implantitis has created difficulty in the management of those complications. The aim of this review was to evaluate the reliability of the diagnosis methods and to provide a set of guidelines to treat peri-implant diseases. A search of PubMed and a hand search of articles related to peri-implant diseases were conducted up to August 2013. A summary of the current methods for the diagnosis of peri-implantitis, its potential risk factors, and a flow chart to guide the clinical management of these conditions are presented.

Evaluation of host β-globin gene fragment lengths in peri-implant crevicular fluid during the wound healing process: a pilot study

PURPOSE

To evaluate the host β-globin gene fragment lengths in the cell-free peri-implant crevicular fluid (PICF) during the wound healing process.

MATERIALS AND METHODS

Nineteen patients (25 implants) were recruited into this study. As part of the control group, gingival crevicular fluids (GCF) from healthy teeth were collected before implant placement. PICF specimens from each implant were collected during weeks 2 to 12 after implant placement. All GCF and PICF specimens were centrifuged to collect the supernatant as cell-free DNA. Five primer pairs specific to the β-globin gene for amplifying 110-base pair (bp), 325-bp, 408-bp, 536-bp, and 2-kilo-base pair (kb) amplicons were used to evaluate DNA fragment lengths with conventional polymerase chain reaction (PCR). The longest PCR amplicon of each specimen was recorded.

RESULTS

The number of 536-bp amplicons (10 of 25 implant specimens) and 2-kb amplicons (8 of 25 implant specimens) in week 2 was higher than at the other visits. In the study, the mucositis group showed the highest number of 536-bp amplicons (22 of 34 implant specimens) and 2-kb amplicons (12 of 34 implant specimens), whereas the healthy implant group showed a low number of 536-bp amplicons (3 of 66 implant specimens), and the cell-free PICF specimens had no 2-kb amplicons. Furthermore, 325-bp and 110-bp amplicons were similar in number in the control teeth and healthy implants.

CONCLUSION

There was a difference in the number of the longest amplicons of cell-free PICF specimens between the mucositis and healthy implant groups. This pilot study suggests that the PCR amplicon lengths of β-globin gene fragments in cell-free PICF specimens might be used as a biomarker to monitor soft tissue inflammation around implants.

Peri-implant diseases: an overview

The use of dental implants in replacing missing teeth is proven to be a valid treatment with a high success rate. To achieve the best treatment outcome in all implant systems, the implant has to be able to integrate with the surrounding tissue. However, dental implants are affected by peri-implant diseases and may fail as a result. As the number of implants placed continues to increase, the prevalence of peri-implant disease will also increase. This requires preventive measures to inhibit the development of the disease and stop its progression. Clinical Relevance: Understanding how to maintain healthy peri-implant tissue as well as diagnosis and treatment of disease are vital for every dentist and dental student.

Treatment of peri-implantitis and the failing implant

Appropriate treatment of implants is becoming increasingly important for the general dentist as the number of implants placed per year continues to increase. Early diagnosis of peri-implantitis is imperative; initiating the correct treatment protocol depends on a proper diagnosis. Several risk factors exist for the development of peri-implantitis, which can guide patient selection and treatment planning. Treatment of peri-implantitis should be tailored to the severity of the lesion (as outlined by the cumulative interceptive supportive treatment protocol), ranging from mechanical debridement to explantation. Several surgical and nonsurgical treatment alternatives exist. There is little consensus on superior treatment methods.

A controlled, cross-sectional exploratory study on markers for the plasminogen system and inflammation in crevicular fluid samples from healthy, mucositis and peri-implantitis sites

PURPOSE

To investigate expression of gene markers for the plasminogen system, inflammation, and bone resorption/remodelling in peri-implant crevicular fluid samples from healthy subjects, subjects with mucositis and subjects with peri-implantitis. A possible inhibitory effect of suppuration on the analysis of gene expression in samples from subjects with peri-implantitis was also analysed.

MATERIALS AND METHODS

Peri-implant crevicular fluid (PICF) was sampled from 25 healthy subjects (H), 25 subjects with mucositis (M) and 25 subjects with peri-implantitis (P) using paper points and suction tips. The samples were analysed by quantitative polymerase chain reaction (qPCR). The following biomarkers associated with the plasminogen system, inflammation and bone resorption/ remodelling were investigated: interleukin-1 beta (IL-1β), interleukin 8 (IL-8), tissue plasminogen activator (tPA), plasminogen activator inhibitor 2 (PAI-2), tartrate-resistant acid phosphatase (TRAP) and cathepsin K (CatK).

RESULTS

IL-1β and IL-8 were significantly upregulated in the P group, and tPA and PAI-2 were significantly upregulated in the M group. These four genetic markers were oppositely regulated in samples from the subjects in the mucositis compared with the peri-implantitis group. TRAP and CatK showed no differences between the groups. The presence of suppuration did not have a detectable effect on gene analysis in samples from subjects with peri-implantitis.

CONCLUSIONS

Markers for the plasminogen system and inflammation could be used to distinguish between mucositis and peri-implantitis. The results suggested that the plasminogen system was sufficiently upregulated allowing for resolution of inflammation and healing at the inflamed implant site in subjects with mucositis, whereas such upregulation was insufficient resulting in impaired healing and prolonged inflammation in subjects with peri-implantitis. The combination of tissue inflammation and low levels of tPA was a strong predictor of marginal bone loss in this study. It may be an interesting candidate for the unambiguous diagnosis of mucositis and peri-implantitis independent of radiographs and could possibly constitute a powerful future tool for rapid assessment of the periimplant tissue condition and the effect of subject treatment.

Peri-implantitis diagnosis and treatment by New Zealand periodontists and oral maxillofacial surgeons

OBJECTIVES

This study aimed to investigate the understanding, diagnosis and management of peri-implantitis by New Zealand periodontists and oral maxillofacial surgeons (OMFS).

DESIGN

Telephone interviews (in combination with a postal and electronic survey) were conducted of all 25 periodontists and 32 OMFS listed as specialists on the New Zealand Dental Register. A seven item multi-choice and short answer questionnaire was used to investigate: their definition of peri-implantitis; the number of annual referrals received in their practice for this condition; their diagnostic, preventive and treatment strategies for peri-implantitis; and their perception of the role of general dental practitioners in its management.

RESULTS

The participation rate was 84.6%. Most respondents defined peri-implantitis as a disease of multifactorial aetiology that leads to destruction of the bone supporting an implant. The average number of cases seen annually differed between periodontists (11 cases/year) and OMFS (4 cases/year). The criteria used by the respondents to diagnose peri-implantitis included increased probing depths and radiographic evidence of bone loss. Each type of specialist used mechanical debridement for treatment, but a higher proportion of OMFS performed surgical procedures as treatment. The prevention strategies used smoking cessation advice and ensuring good plaque control. All respondents agreed that peri-implantitis is an important disease that can lead to implant failure, and all acknowledged the role of general dental practitioners in diagnosis, referral for treatment and long-term implant maintenance.

CONCLUSION

The definition, diagnostic criteria and management strategies used by New Zealand specialists are generally consistent with those found in the literature. No evidence-based, gold standard treatment protocol for peri-implantitis has been identified in the literature, and New Zealand specialists use a range of treatment modalities.

Peri-implantitis: etiology, diagnosis and treatment: an update

Peri-implant mucositis is described as the presence of inflammation in the mucosa around implants without any bone loss. By contrast, in peri-implantitis, besides the inflammation in the peri-implant mucosa, loss of supporting bone is also seen. The probing depth, the presence of bleeding on probing, suppuration and radiographs should be assessed regularly for the diagnosis of peri-implant diseases. Poor oral hygiene, smoking and previous history of periodontitis are known risk factors for the disease. The occlusion and longevity of fixed partial dentures around implants, whether connected to the natural teeth or not, is still an area of investigaton, but studies show that long-term results are acceptable for both. Various treatment modalities are discussed in relation to the management of periimplantitis. The predictable outcome of peri-implantitis management is not yet known.

[Clinical, microbiological and immunological findings in peri-implantitis patients with bar-retained lower removable partial dentures, compared to a healthy control group (12-month-follow-up)]

Cause, treatment strategies and prognosis of peri-implantitis is not well understood. The aim of this study was to followup clinical, microbiological and immunological findings in individuals wearing bar-retained lower partial dentures with and without peri-implantitis, pre and post treatment. From the Tuebingen Implant Registry recall program 16 peri-implantitis patients were compared to 16 healthy individuals in a prospective, unblinded study. Peri-implantitis was treated with a single anti-inflammatory therapy according to the CIST protocol while the controls received professional implant cleaning. The following findings were recorded at four time points before treatment (T1) and 30, 90, 360 days post treatment (T2-T4): sulcular fluid flow rate, probing depth, plaque and bleeding index, implant stability (Periotest); sulcular concentrations of interleukin-1 beta, plasminogen activator inhibitor 2, prostaglandin E2, and the sum score of five periodonto-pathogenic bacteria species by PCR (Hain Microldent test). Statistically significant differences between healthy and diseased implants were found for probing depth, bleeding on probing, bacterial load, and implant stability. For the first three, a significant decrease in severity was observed after treatment, but reached initial pre-treatment values within one year. No changes could be observed in the individuals without peri-implantitis. The results of the present study confirm marked differences in peri-implant findings between healthy and diseased sites. They demonstrate that a single anti-inflammatory intervention can initially--but not sustained--reduce probing depth, bleeding on probing, and the total bacterial load as evident from PCR diagnostics. Further immunological diagnostic measures do not seem to provide more information in the patients investigated.

Implant complications: risk evaluation, diagnosis, management and outcomes

Dental implants and their restorations have become an accepted and predictable modality of treatment. The literature reflects excellent long-term survival rates. However, survival of an implant does not necessarily translate to success, and in between these two outcomes lies the world of implant complications. Complications associated with dental implants occur with both the restorative and surgical components, with the restorative component complications being more frequent and to some extent, more easily managed. Surgical complications are difficult to manage, and can be the result of many aspects of the implant surgery. Potential complications can arise from poor planning, poor case selection, and poor execution. Complications can also occur where no technical or surgical errors are apparent, but where biology and the fundamental flaw of the trans-mucosal design of dental implant prostheses, adversely affects the outcome. This presentation outlines the nature of potential complications and looks at practical and pragmatic methods, first to try to prevent complications, through improved case selection and execution; secondly, it discusses the most effective methods to prevent complications in implants already installed, by adequate maintenance programmes. Lastly, it deals with those cases which require clinical management of the complications. This presentation provides the clinician with a greater understanding of the difficulties in managing implants that are not progressing as we, the clinicians, and the patients, had originally expected.

Guidance for the maintenance care of dental implants: clinical review

As implant treatment becomes part of mainstream dental therapy, dental offices should implement protocols for individualized, systematic and continuous supportive care of the peri-implant tissues. This review article suggests guidelines for maintenance care of dental implants. The preliminary assessment should begin with updating the patient's medical and dental histories. The clinical implant should be examined to evaluate the following: condition of the soft tissues, plaque index, clinical probing depth, bleeding on probing, suppuration, stability of soft-tissue margins, keratinized tissue, mobility and occlusion. If the clinical signs suggest the presence of peri-implantitis, radiography of the site is advisable, to confirm the diagnosis. Appropriate treatment should be pursued according to any diagnosis reached during the examination, including (but not limited to) instructions on oral hygiene, removal of supra- and sub-gingival plaque and calculus, occlusal adjustment, relining of a removable prosthesis or surgery.