Peri-implantitis. Part 2: Prevention and maintenance of peri-implant health

Cell Responses to Calcium- and Protein-Conditioned Titanium: An In Vitro Study

Dental implants have become the leading choice for patients who lose teeth; however, dental implantation is challenged by peri-implant infections. Here, calcium-doped titanium was fabricated by the combinational use of thermal evaporation and electron beam evaporation in a vacuum; then, the material was immersed in a calcium-free phosphate-buffered saline solution containing human plasma fibrinogen and incubated at 37 °C for 1 h, creating calcium- and protein-conditioned titanium. The titanium contained 12.8 ± 1.8 at.% of calcium, which made the material more hydrophilic. Calcium release by the material during protein conditioning was able to change the conformation of the adsorbed fibrinogen, which acted against the colonization of peri-implantitis-associated pathogens (Streptococcus mutans, UA 159, and Porphyromonas gingivalis, ATCC 33277), while supporting the adhesion and growth of human gingival fibroblasts (hGFs). The present study confirms that the combination of calcium-doping and fibrinogen-conditioning is a promising pathway to meeting the clinical demand for suppressing peri-implantitis.

Peri-implantitis after 40 years: Evidence, mechanisms, and implications: A mapping review

STATEMENT OF PROBLEM

The high prevalence of peri-implantitis (PI) continues to plague patients and the disease is resistant to present treatment regimens. An analysis of the available research is lacking.

PURPOSE

Given the abundance and diversity of research on the topic of PI, the purpose of this mapping review was to synthesize the literature on the prevention of PI, the histopathology of the disease, the state of present therapeutics, and any emerging treatments.

MATERIAL AND METHODS

An extensive literature search was undertaken by using the electronic databases of PubMed, Web of Science, and Science Direct. The keyword strings were peri-implantitis, dental implant, risk assessment, histopathology, prosthesis design, and treatment. The filters applied were time interval from 2000 to 2002; language, English.

RESULTS

A total of 3635 articles were taken from PubMed, 3686 articles from Web of Science, and 2450 articles from Science Direct. After applying the inclusion and exclusion criteria to the titles and abstracts of selected investigations, 214 studies were retrieved.

CONCLUSIONS

The evidence reflects a concerning incidence of PI, without a predictable treatment protocol. An in-depth patient risk assessment considering risk modification, emphasis on surgical and restorative expertise, and strict recall and maintenance is essential to minimize PI.

Enzymatic biofilm destabilisation to support mechanical cleansing of inserted dental implant surfaces: an in-vitro pilot study

Peri-implantitis is caused by microbial contamination and biofilm formation on the implant surface. To achieve re-osseointegration, the microbes must be completely removed from the surface. Adjunctive to mechanical cleaning, chemical treatment with enzymes or other substances could optimise the treatment outcome. Therefore, we investigated the efficacy of different enzymes, a surfactant, and a chelator in destabilising dental polymicrobial biofilm. The biofilm destabilising effect of the glycosidases α-amylase, dextranase, DispersinB^®, and lysozyme, as well as the proteinase subtilisin A, and the nuclease Benzonase^®, the chelator EDTA, and the surfactant cocamidopropyl betaine were investigated on biofilms, inoculated with plaque on rough titanium discs. The test and the control solutions were incubated for 15 min at 36 °C on biofilms, and loosened biofilm mass was removed by shear stress with a shaker. Fluorescence-stained biofilms were microscopically analysed. Acceptable cell tolerability concentrations of test substances were determined by the MTT (tetrazolium dye) assay on the MG-63 cell line. A statistically significant biofilm destabilising effect of 10% was shown with lysozyme (2500 µg/ml).

Risk indicators for mucositis and peri-implantitis: results from a practice-based cross-sectional study

Purpose

This practice-based cross-sectional study aimed to investigate whether common risk indicators for peri-implant diseases were associated with peri-implant mucositis and peri-implantitis in patients undergoing supportive implant therapy (SIT) at least 5 years after implant restoration.

Methods

Patients exclusively restored with a single implant type were included. Probing pocket depth (PPD), bleeding on probing (BOP), suppuration, and radiographic bone loss (RBL) were assessed around implants. The case definitions were as follows: peri-implant mucositis: PPD ≥4 mm, BOP, no RBL; and peri-implantitis: PPD ≥5 mm, BOP, RBL ≥3.5 mm. Possible risk indicators were compared between patients with and without mucositis and peri-implantitis using the Fisher exact test and the Wilcoxon rank-sum test, as well as a multiple logistic regression model for variables showing significance (P<0.05).

Results

Eighty-four patients with 169 implants (observational period: 5.8±0.86 years) were included. A patient-based prevalence of 52% for peri-implant mucositis and 18% for peri-implantitis was detected. The presence of 3 or more implants (odds ratio [OR], 4.43; 95 confidence interval [CI], 1.36-15.05; P=0.0136) was significantly associated with an increased risk for mucositis. Smoking was significantly associated with an increased risk for peri-implantitis (OR, 5.89; 95% CI, 1.27-24.58; P=0.0231), while the presence of keratinized mucosa around implants was associated with a lower risk for peri-implantitis (OR, 0.05; 95% CI, 0.01-0.25; P<0.001).

Conclusions

The number of implants should be considered in strategies to prevent mucositis. Furthermore, smoking and the absence of keratinized mucosa were the strongest risk indicators for peri-implantitis in patients undergoing SIT in the present study.

Patient compliance as a risk factor for the outcome of implant treatment

Peri-implantitis can be explained using a multicausality model. Many factors are involved in the etiology of peri-implantitis, but patient compliance also plays a key role. Oral hygiene, attending recall visits, smoking behavior, and therapy comprehension are relevant factors that contribute to peri-implant health. The clinician should create the most optimal conditions for patients to facilitate adequate oral self-care and to help patients improve their oral hygiene skills. Implementation of a supportive periodontal therapy program is mandatory to control inflammation and plaque accumulation, as well as to keep the incidence of peri-implant diseases low. Patient compliance, including plaque control and dental follow-up, must be optimal. Consequently, precautions must be taken with patients treated with dental implants.

Genetic Involvement in Dental Implant Failure: Association With Polymorphisms of Genes Modulating Inflammatory Responses and Bone Metabolism

Implant loss is the most serious complication of dental implants. Although the problems and causes behind the implant failure are clearly defined today, determination of the underlying causes of failure varies by the case. The clusterization phenomenon of implant loss (multiple implant failures) implies the existence of genetic risk factors. Inflammation has a critical effect on osseointegration and implant success. Peri-implantitis is an inflammatory disease of tissue supporting the tooth or implant. Inflammation leads to loss of support tissue, particularly bone, resulting in failure of implants. A single nucleotide polymorphism (SNP) of pro-inflammatory mediator genes may affect their expression levels or amino acid sequence, and, consequently, the host inflammatory response. Since the end of the past century, many studies have been conducted to investigate the association of SNP with implant failure and related conditions. Involvement of several groups of genes-including interleukins, tumor necrosis factor-α, matrix metalloproteinases, and growth factors involved in immune regulation, inflammatory response, and bone metabolism-has been explored. Some have been found to be associated with implant loss and considered potential genetic risk factors for implant failure. In this review, we summarize results of recent studies of impact of genetic factors on dental implant failure.

Peri-implantitis and the prosthodontist

Peri-implantitis has been described as progressive crestal bone loss around a dental implant. The condition is poorly understood, and is challenging to manage; it is commonly and widely attributed to issues with the implant, the implant surface, surgical technique and oral hygiene. The effect of prosthodontic stages of treatment on the postoperatively established state has not been adequately investigated. It is the authors' contention that the manner in which the implant is restored contributes significantly to prognosis and peri-implant disease experience, and that the role of prosthodontic aspects of treatment in the causation of peri-implantitis may be seriously underestimated. The prosthodontist has a clear role and responsibility in the avoidance of future peri-implant problems by ensuring that implants are restored in an entirely biologically and biomechanically sound manner. The number of implant treatments carried out year-on-year is rising apace, with more and more implants being restored in general dental practice. With the rapid emergence of lower cost dental implant systems and a broadening range of generic restorative options and components for well-established systems, there is an increasing need to consider and understand how the implant restorative process may have a negative impact upon the peri-implant tissues, and how this effect may be minimised and peri-implant health promoted and maintained by paying attention to detail throughout the entire process.

Clinical applications of polytetrafluoroethylene (PTFE) tape in restorative dentistry

Restorative dental procedures are ever developing; one reason for this can be attributed to newer materials with better handling properties and our ability to manipulate them more effectively. As a result various techniques have been described to aid clinicians in obtaining predictable results in restorative dental procedures. This article aims to review the use of plumber's tape to assist in adhesive, endodontic and implant related dental procedures, when compared to other available materials.

Esthetic Evaluation of Implant-Supported Single Crowns: The Implant Restoration Esthetic Index and Patient Perception

PURPOSE

To test the validity and reliability of a newly developed Implant Restoration Esthetic Index (IREI) and to compare esthetic outcomes reported by patients and professionals.

MATERIALS AND METHODS

Ten graduate students and 10 prosthodontists assessed esthetic outcomes of 27 single-tooth implants with the IREI. Six peri-implant soft tissue parameters were measured using visual analog scales: mesial papilla presence, distal papilla presence, gingival trigone, soft tissue curvature, alveolar process deficiency, and soft tissue color and texture, as well as the six crown parameters: crown contour, crown position, crown labial convexity, crown characterization, crown color and translucency, and abutment visibility. The validity was tested based on Pearson's correlation. The internal consistency reliability was analyzed by Cronbach's alpha. Interclass correlation coefficients (ICC) were calculated to express the test-retest reliability and the inter-rater reliability. The correlations between patient and professional evaluations were analyzed by Pearson's correlation.

RESULTS

The IREI demonstrated significant correlation (p < 0.05) to the pink esthetic score and white esthetic score (PES/WES). The internal consistency reliability showed a Cronbach's Alpha of 0.830. The test-retest reliability was excellent in both the graduate student group and the prosthodontist group, with ICCs of 0.961 and 0.952, respectively (p < 0.05). The inter-rater reliability was acceptable, with ICCs of 0.649 and 0.667, respectively (p < 0.05). Low correlation coefficients were found between patient and professional evaluations.

CONCLUSIONS

The results of this study indicated that the IREI was considered a valid and reliable index involving sufficient parameters for professional esthetic evaluation of single-tooth implant restorations. The patient-reported esthetic outcomes had poor or no significant correlation to professional-reported outcomes.

Health, Maintenance, and Recovery of Soft Tissues around Implants

BACKGROUND

The health of peri-implant soft tissues is one of the most important aspects of osseointegration necessary for the long-term survival of dental implants.

PURPOSE

To review the process of soft tissue healing around osseointegrated implants and discuss the maintenance requirements as well as the possible short-comings of peri-implant soft tissue integration.

MATERIALS AND METHODS

Literature search on the process involved in osseointegration, soft tissue healing and currently available treatment modalities was performed and a brief description of each process was provided.

RESULTS

The peri-implant interface has been shown to be less effective than natural teeth in resisting bacterial invasion because gingival fiber alignment and reduced vascular supply make it more vulnerable to subsequent peri-implant disease and future bone loss around implants. And we summarized common procedures which have been shown to be effective in preventing peri-implantitis disease progression as well as clinical techniques utilized to regenerate soft tissues with bone loss in advanced cases of peri-implantitis.

CONCLUSION

Due to the difference between peri-implant interface and natural teeth, clinicians and patients should pay more attention in the maintenance and recovery of soft tissues around implants.