Vancomycin and tobramycin impregnated mineralized allograft for the surgical regenerative treatment of peri-implantitis: a 1-year follow-up case series

Selecting biomaterials in the reconstructive therapy of peri-implantitis

Peri-implantitis is a pathogenic inflammatory condition characterized by progressive bone loss and clinical inflammation that may compromise the stability of dental implants. Therapeutic modalities have been advocated to arrest the disorder and to establish peri-implant health. Reconstructive therapy is indicated for bone defects exhibiting contained/angular components. This therapeutic modality is based upon the application of the biological and technical principles of periodontal regeneration. Nonetheless, the comparative efficacy of reconstructive therapy and nonreconstructive modalities remains unclear. Therefore, the aim of this narrative review is to address major clinical concerns regarding the efficacy, effectiveness, and feasibility of using biomaterials in peri-implantitis therapy. In particular, the use of bone grafting materials, barrier membranes, and biologics is comprehensively explored.

A Systematic Review and Meta-Analysis of Systemic and Local Antibiotic Therapy in the Surgical Treatment of Peri-Implantitis

(1) Background: Given the existing controversy regarding the use of antibiotics in the treatment of peri-implantitis, this systematic review and meta-analysis aim to ascertain how beneficial the role of systemic and local antibiotics is in peri-implant surgical therapy, considering the harmful effects that they represent and the abuse of antibiotics in terms of global health. (2) Methods: To determine the therapeutic efficacy of the administration of antibiotics in the surgical treatment of peri-implantitis in terms of probing pocket depth (PPD) and bleeding on probing (BoP), electronic and manual bibliographic searches were carried out in the Embase and PubMed databases, collecting data that related to before and after treatment. (3) Results: The adjunctive use of local antibiotics provides significant improvements in PPD (MD = 1.29; 95% CI: 0.56 to 2.02; p ≤ 0.0006; I² = 0%) when compared with surgical treatment alone. No significant differences were found in the other subgroup; that is, the use of systemic antibiotics did not significantly improve PPD changes in the surgical treatment of peri-implantitis (MD = 0.40; 95% CI: -0.15 to 0.95; p = 0.15; I² = 0). (4) Conclusions: The use of local antibiotics in the surgical treatment of peri-implantitis seems to offer treatment improvements in terms of PPD and BoP, unlike that observed with the use of systemic antibiotics. However, these results should be taken with caution as they also depend on the type of surgical technique used, whether regenerative or resective. More research is needed on this topic to understand the role of local and systemic antibiotics in the treatment of peri-implantitis.

Significance of barrier membrane on the reconstructive therapy of peri-implantitis: A randomized controlled trial

BACKGROUND

The objective of this trial was to investigate the clinical and radiographic significance of using a mixture of mineralized and demineralized allografts in combination (M) or not (NM) with a resorbable cross-linked barrier membrane in the reconstructive therapy of peri-implantitis defects.

METHODS

A two-arm randomized clinical trial was performed in patients diagnosed with peri-implantitis that exhibited contained defects. Clinical parameters were recorded at baseline (T₀ ), 6 months (T₁ ), and 12 months (T₂ ). Radiographic parameters were recorded at T₀ and T₂ . A composite criterion for disease resolution was defined a priori. A generalized linear model of repeated measures with generalized estimation equation statistical methods was used.

RESULTS

Overall, 33 patients (n_implants  = 48) completed the study. At T₂ , mean disease resolution was 77.1%. The use of a barrier membrane did not enhance the probability of disease resolution at T₂ (odds ratio [OR] = 1.55, p = 0.737). Conversely, the odds of disease resolution were statistically associated with the modified plaque index recorded at T₀ (OR = 0.13, p = 0.006) and keratinized mucosa width (OR = 2.10, p = 0.035). Moreover, women exhibited greater odds to show disease resolution (OR = 5.56, p = 0.02).

CONCLUSION

Reconstructive therapy by means of a mixture of mineralized and demineralized allografts is effective in clinically resolving peri-implantitis and in gaining radiographic marginal bone level. The addition of a barrier membrane to reconstructive therapy of peri-implantitis does not seem to enhance the outcomes of contained bone defects (NCT05282667).

Minimal invasiveness in the reconstructive treatment of peri-implantitis defects

Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, clinically characterized by increased peri-implant probing pocket depth and progressive loss of supporting bone. Consequently, to arrest further disease progression and to increase the chance to obtain re-osseointegration, surgical reconstructive procedures have been adopted. In particular, following a paradigm gathered from periodontal therapy, recent protocols have underlined the importance of a minimally invasive approach to optimize the outcomes of therapy while minimizing the risks of postoperative complications. The present review summarizes the level of evidence on the surgical reconstructive protocols focusing on the new approaches aiming to minimize surgical trauma and patients' postoperative discomfort, underlining the pros and cons of each treatment modality.

A Systematic Review and Meta-Analysis of Systemic Antibiotic Therapy in the Treatment of Peri-Implantitis

Research has been conducted into the advantages of the systemic administration of antibiotics. The aim of this systematic review and meta-analysis was to assess the efficacy of systemic antibiotic administration in the treatment of peri-implantitis in terms of bleeding on probing (BoP) and probing pocket depth (PPD). Literature searches were performed across PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) to identify randomized controlled trials and observational clinical studies. After peri-implantitis treatment, PPD was reduced by 0.1 mm (p = 0.58; IC 95% [-0.24, 0.47]), indicating a non-significant effect of antibiotic administration on PPD. The BoP odds ratio value was 1.15 (p = 0.5; IC 95% [0.75, 1.75]), indicating that the likelihood of bleeding is almost similar between the test and control groups. Secondary outcomes were found, such as reduced clinical attachment level, lower suppuration and recession, less bone loss, and a reduction in total bacterial counts. In the treatment of peri-implantitis, the systemic antibiotic application reduces neither PPD nor BoP. Therefore, the systemic administration of antibiotics, in the case of peri-implantitis, should be rethought in light of the present results, contributing to address the problem of increasing antibiotic resistance.

Implantoplasty- provoking or reducing inflammation? - a systematic scoping review

OBJECTIVES

To evaluate clinical parameters associated with inflammation after adjunctive implantoplasty in conjunction with surgical treatment of peri-implantitis.

MATERIALS AND METHODS

A systematic literature search was performed in 2 databases until 29. December 2020 to find publications that report on clinical parameters after surgical peri-implantitis treatment which included adjunctive implantoplasty. Clinical studies on implantoplasty reporting on BoP as outcome were included, but other clinical or radiographic outcomes were also considered.

RESULTS

The search resulted in 18 articles that fulfilled the inclusion criteria. The results indicated improvements of BoP and clinical parameters following surgical peri-implantitis treatment with adjunctive implantoplasty.

CONCLUSIONS

Within its limits, the findings of the present scoping review indicated that BoP is reduced following surgical peri-implantitis treatment with adjunctive implantoplasty, and that this improvement is in line with surgical peri-implantitis treatment without adjunctive implantoplasty.

Surgical therapy of peri-implantitis

Peri-implantitis is caused by a bacterial challenge; therefore, anti-infective treatment strategies should be employed to manage the disease. As nonsurgical approaches demonstrate limited efficacy in most cases of peri-implantitis, surgical interventions are often required. Treatment outcomes improve following access flap surgery, with or without adjunctive resective and/or augmentation measures. Whereas nonaugmentative therapies (ie, access flap surgery and resective techniques) primarily aim to resolve inflammation and arrest further disease progression, augmentation approaches also seek to regenerate the bony defect and achieve reosseointegration. Currently, limited evidence supports the superiority of augmentative surgical techniques for peri-implantitis treatment over nonaugmentation methods, and human histologic evidence for reosseointegration is sparse. For patients involved in regular postoperative maintenance programs, success of peri-implantitis surgical treatment based on various definitions of success was obtained in over half of the cases after 5-7 years. Despite surgical treatment, cases of further disease progression that required retreatment or led to implant loss were reported.

Surgical approach combining implantoplasty and reconstructive therapy with locally delivered antibiotic in the treatment of peri-implantitis: A prospective clinical case series

BACKGROUND

Nonsurgical treatment, resective surgery, reconstructive surgery, or combined approaches have been proposed for the treatment of peri-implantitis, with variable results.

PURPOSE

To evaluate the 1-year clinical and radiographic outcomes following combined resective and reconstructive surgical treatment with topical piperacillin/tazobactam antibiotic in the management of peri-implantitis.

MATERIAL AND METHODS

Forty-three patients diagnosed with peri-implantitis were included. Surgical treatment consisted of implantoplasty of the supra-crestal component of the defect, the application of a topical antibiotic solution over the implant surface, and subsequent reconstruction of the intra-osseous component of the peri-implant defect. The primary outcome was disease resolution, defined as the absence of bleeding on probing (BoP) and/or suppuration on probing (SoP), a peri-implant pocket probing depth (PPD) ≤5 mm, and no bone loss >0.5 mm 1 year after surgery. Secondary outcomes included changes in BoP, PPD, SoP, and peri-implant marginal bone levels. One implant per patient was included in the analysis.

RESULTS

The treatment success rate of the 43 dental implants included in the study was 86% at 1 year after surgery. Mean PPD and BoP decreased from 6.41 ± 2.11 mm and 100% at baseline to 3.19 ± 0.99 mm (p < 0.001) and 14% (p < 0.001) at 1 year, respectively. SoP was significantly reduced from 48.8% at baseline to 0% 1 year after surgery (p < 0.001). Radiographically, a mean defect fill of 2.64 ± 1.59 mm was recorded (p < 0.001).

CONCLUSIONS

The combination of a resective and reconstructive surgical approach together with locally delivered antibiotic achieved a high disease resolution rate after 1 year of follow-up and constitutes a viable option for the management of peri-implantitis.

Changes in peri-implant soft tissue levels following surgical treatment of peri-implantitis: A systematic review and meta-analysis

AIM

To assess the changes in peri-implant soft tissue levels after the surgical treatment of peri-implantitis.

METHODS

Randomized controlled trials, controlled clinical trials, cohort studies and case series, evaluating the changes in the position of the mucosal margin before and after surgical treatment of peri-implantitis, were searched. Secondary outcomes were changes in keratinized mucosa (KM), radiographic bone levels, probing depths (PD), plaque indices, bleeding on probing and patient perception. Meta-analyses were performed to determine weighted mean differences (WMD) or effects (WME).

RESULTS

Twenty-six articles, reporting 20 investigations, were included. Reconstructive approaches yielded significantly less increase in mucosal recession, when compared to access flaps (n = 3, WMD = -1.35 mm, 95% confidence interval [CI] [-2.62; -0.07], p = .038). When comparing among reconstructive surgical interventions similar outcomes were observed irrespective of the use of a barrier membrane (n = 3, WMD = -0.01 mm, 95% CI [-0.15; 0.13], p = .917). When considering the effects over time, limited mucosal recession was observed after reconstructive procedures (n = 23, WME = 0.389 mm, 95% CI [0.204; 0.574]), p = .001), while increased recession was reported with either resective or access flap surgery (n = 6, WME = 1.21 mm, 95% CI [0.70; 1.72], p = <.001; and n = 3, WME = 0.95 mm, 95% CI [0.20; 2.10], p = .106; respectively). When resective and reconstructive approaches were combined the highest values on peri-implant recession were reported (n = 2, WME = 1.97 mm, 95% CI [0.81; 3.14], p < .001). Reconstructive surgical interventions were associated with greater radiographic bone level gains, while similar values were reported for PD reduction when comparing reconstructive, access and resective procedures.

CONCLUSIONS

Resective surgical procedures were associated with significant post-surgical recession while minimal recession was observed in regenerative interventions.

Peri-Implantitis Regenerative Therapy: A Review

Simple Summary

Regenerative therapies are one of the options to treat peri-implantitis diseases that cause peri-implant bone loss. This review reports classic and current literature to describe the available knowledge on regenerative peri-implant techniques.

Abstract

The surgical techniques available to clinicians to treat peri-implant diseases can be divided into resective and regenerative. Peri-implant diseases are inflammatory conditions affecting the soft and hard tissues around dental implants. Despite the large number of investigations aimed at identifying the best approach to treat these conditions, there is still no universally recognized protocol to solve these complications successfully and predictably. This review will focus on the regenerative treatment of peri-implant osseous defects in order to provide some evidence that can aid clinicians in the approach to peri-implant disease treatment.

Effect of Local Delivery of Vancomycin and Tobramycin on Bone Regeneration

OBJECTIVE

A bone defect rat model was established to investigate the osteogenic effect of local delivery two antibiotics (vancomycin and tobramycin powder) on bone regeneration.

METHODS

Twenty-four Sprague-Dawley (SD) male rats (6 to 8 weeks, 200 to 250 g) were used in this study. All these rats were randomly divided into four groups. Based on dose conversion between rat and human via body surface area, the rat dose of two antibiotics was 88μg/g and 176 μg/g for vancomycin and tobramycin, respectively. Con group (no antibiotic), Van group (vancomycin, 88 μg/g), Tob group (tobramycin 176 μg/g), and Van+Tob group (vancomycin 88μg/g combined with tobramycin 176 μg/g). A 5.0-mm full-thickness standardized mandibular bone defect was performed with a drill in each rat and different antibiotic powders were placed over the bone defect space, respectively. All these animals were sacrificed after 12 weeks post-operation. The mandible bones were harvested for further radiographic and histologic analysis. The bone volume/total volume (BV/TV) ratio, bone volume (BV), and bone fractional area (BFA) in the defect area via micro-computed tomography (μCT scanning) were further analyzed. Then, we performed a histological assessment via hematoxylin and eosin (H&E) and Masson's trichrome staining to analyze bone regeneration and also analyze the number of osteoblasts per filed.

RESULTS

There were no postoperative deaths, signs of vancomycin-related or tobramycin-related toxicity, or signs of systemic illness in any of the four groups. All wounds healed well, and no complications or surgical site infection were observed in all rats. From the μCT scans analyses, there was less bone regeneration in the Van group than in the Con group (BV/TV: F = 64.29, R²  = 0.9602; P = 0.0052; BFA: F = 76.17, R²  = 0.9662, P = 0.0007; BV: F = 194.4, R²  = 0.9865, P = 0.0022). However, when the tobramycin and vancomycin were combined, an increase in bone defect re-ossification was found in the Van+Tob group than in the Van group (BV/TV: F = 64.29, R²  = 0.9602, P = 0.0033; BFA: F = 76.17, R²  = 0.9662, P = 0.0006; BV: F = 194.4, R²  = 0.9865, P = 0.0033). Routine H&E and Masson staining supported the finding of μCT scanning. Quantitative indices confirmed that both the bone regeneration and the number of osteoblasts per filed in the defect area was higher in the Van+Tob group than in the Van group (percentage of bone tissue: F = 145.7, R²  = 0.9562, P = 0.0008; number of osteoblasts per file; F = 67.3, R²  = 0.9098, P < 0.0001). There was no significant difference between the Con group and the Van+Tob group on the number of osteoblasts each field (F = 145.7, R²  = 0.9562, P > 0.9999).

CONCLUSION

For bone defect, local application of vancomycin combined with tobramycin was recommended over vancomycin alone. This animal study presents data suggesting that the use of local delivery of vancomycin and tobramycin should be investigated further in clinical studies.

Resolution of peri-implantitis by means of implantoplasty as adjunct to surgical therapy: A retrospective study

BACKGROUND

There is a paucity of data on the effectiveness of implantoplasty as adjunct to the surgical management of peri-implantitis.

PURPOSE

To evaluate the resolution of peri-implantitis by means of implantoplasty as adjunct to surgical resective (RES) and reconstructive (REC) therapies and supportive maintenance.

METHODS

Patients that underwent surgical therapy to manage peri-implantitis with a follow-up of ≥12 months and enrolled in a regular peri-implant supportive care were recruited. RES group consisted of two interventions that included osseous recontouring and apically position flap (APF) and soft tissue conditioning (STC). REC was performed in the infra-osseous compartment of combined defects. Implant survival rate was recorded. Clinical and radiographic parameters were evaluated to define a "dogmatic" (case definition #1) and a "flexible" (case definition #2) therapeutic success. Univariate and multivariate multilevel backward logistic regression were applied for statistical analysis.

RESULTS

Overall, 43 patients (n_implants  = 135) were retrospectively assessed. Mean observational period was ∼24 months. Implant survival rate was 97.8%, being significantly higher for APF, STC, and APF + STC (RES) when compared with REC (P = 0.01) therapy, in particular for advanced lesions (>50% of bone loss). The overall therapeutic success rate at implant-level was 66% and 79.5% for case definition #1 and #2, respectively. APF group displayed more efficient disease resolution when considered success definition #1 (72%). Contrarily, when the data were adhered to success definition #2, STC group showed a slightly higher disease resolution rate (87%). For RES group, location, favoring anterior (P = 0.04) and defect type, favoring class II (P = 0.02) displayed statistical significance for therapeutic success. For REC group, implants exhibiting a wider band of keratinized mucosa (KM) demonstrated higher therapeutic success (P = 0.008).

CONCLUSION

Implantoplasty as an adjunct to surgical therapy proved effective in terms of disease resolution and implant survival rate. Implant location, defect morphology as well as the buccal width of KM are indicators of therapeutic success.

Cardiac Differentiation of Mesenchymal Stem Cells: Impact of Biological and Chemical Inducers

Cardiovascular disorders (CVDs) are the leading cause of global death, widely occurs due to irreparable loss of the functional cardiomyocytes. Stem cell-based therapeutic approaches, particularly the use of Mesenchymal Stem Cells (MSCs) is an emerging strategy to regenerate myocardium and thereby improving the cardiac function after myocardial infarction (MI). Most of the current approaches often employ the use of various biological and chemical factors as cues to trigger and modulate the differentiation of MSCs into the cardiac lineage. However, the recent advanced methods of using specific epigenetic modifiers and exosomes to manipulate the epigenome and molecular pathways of MSCs to modify the cardiac gene expression yield better profiled cardiomyocyte like cells in vitro. Hitherto, the role of cardiac specific inducers triggering cardiac differentiation at the cellular and molecular level is not well understood. Therefore, the current review highlights the impact and recent trends in employing biological and chemical inducers on cardiac differentiation of MSCs. Thereby, deciphering the interactions between the cellular microenvironment and the cardiac inducers will help us to understand cardiomyogenesis of MSCs. Additionally, the review also provides an insight on skeptical roles of the cell free biological factors and extracellular scaffold assisted mode for manipulation of native and transplanted stem cells towards translational cardiac research.

The Osteogenic Effect of Local Delivery of Vancomycin and Tobramycin on Bone Marrow Stromal Cells

Purpose

Bone tissue infections are a difficult problem in orthopedic surgery. Topical application of vancomycin and tobramycin powder has been proved to significantly reduce infection rates. However, the osteogenic effect of the topical application of these two antibiotics is unclear. In this study, the osteogenic effect of local delivery antibiotics on bone regeneration was investigated in vitro.

Methods

Bone marrow stromal cells (BMSCs) were incubated in the presence of vancomycin (14.28μg/mL), tobramycin (28.57μg/mL), or vancomycin combined with tobramycin (vancomycin 14.28μg/mL and tobramycin 28.57μg/mL). Cell viability, proliferation, and migration were analyzed. The alizarin red staining as well as the alkaline phosphatase staining was investigated. Then, the quantitative real-time (qRT)-PCR of osteogenic mRNA expression levels were also evaluated.

Results

The results showed that vancomycin combined with tobramycin has no adverse effect on the viability and proliferation of BMSCs. The topical application of vancomycin alone may interfere with the bone regenerative processes. However, the tobramycin can promote the osteogenic differentiation of BMSCs and also rescue the osteogenic potential of BMSCs inhibited by vancomycin both in vitro.

Conclusion

From this in vitro study, local application of vancomycin combined with tobramycin does not affect the osteogenic potential of BMSCs.

Current Insights in the Application of Bone Grafts for Local Antibiotic Delivery in Bone Reconstruction Surgery

Introduction: Bone implant related infection is still one of the biggest challenges in bone and joint surgery. Antibiotic impregnated bone grafts seem to be promising in both treatment and prevention of these infections. However, great variance in methodology predominates this field of research. This paper gives an overview of the published literature.

Methods: The PRISMA-flowchart was used as protocol for article selection. Medline was searched and articles were selected in accordance with predetermined exclusion criteria.

Results: Forty-eight articles were included in the synthesis. Topics including bone graft type, manipulations of the graft, elution profile, bacterial inhibition, osteotoxicity, incorporation, special impregnation methods, clinical use and storage were investigated.

Therapeutically, high initial levels seem appropriate for biofilm eradication. A single stage procedure in the treatment of bone implant related infection seems feasible. Prophylactically, the literature indicates a reduction of postoperative infections when using antibiotic impregnated bone grafts.

Conclusion: Bone grafts are a suitable carrier for local antibiotic application both therapeutically and prophylactically.

Presence of Candida species in the subgingival oral biofilm of patients with peri-implantitis

BACKGROUND

There are no studies that have investigated the presence of Candida species in the subgingival oral biofilm (OB) of patients with peri-implantitis.

PURPOSE

The aim was to assess the presence of Candida species in the subgingival OB of patients with peri-implantitis.

MATERIALS AND METHODS

Individuals with (group A) and without (group B) peri-implantitis were included. Life style related and demographic data were collected using a questionnaire. In both groups, peri-implant plaque-index (PI), bleeding-on-probing (BOP), and probing-depth (PD) were evaluated and crestal bone loss (CBL) were measured on digital bitewing radiographs. In both groups, subgingival OB samples were collected using sterile paper points. Identification of Candida species was performed using ChromAgar medium and colony forming units per milliliter (CFU/mL) were determined. Statistical analysis was performed, and level of significance was set at P < 0.05.

RESULTS

The mean age of individuals in groups A (n = 43) and B (n = 41) were 52.2 ± 4.4 and 55.1 ± 2.3 years, respectively. All participants were male. In groups A and B, implants were in function for 7.4 ± 1.3 and 6.8 ± 0.6 years, respectively. Scores of peri-implant PI (P < 0.001), BOP (P < 0.001), PD (P < 0.001), and CBL (P < 0.001) were significantly higher in group A than group B. Subgingival Candida was isolated from the OB of 33 (76.7%) patients in group A and 5 (12.2%) individuals in group B. The most common yeast species was Candida albicans, which was isolated from 67.4% to 60% individuals in groups A and B, respectively. The number of subgingival oral yeasts CFU/mL were significantly higher in group A (3147.54 ± 1052.6 CFU/mL) compared with group B (496.68 ± 100.2 CFU/mL; P < 0.01).

CONCLUSION

Candida species (predominantly C. albicans) are present in the subgingival OB of patients with peri-implantitis. Community-based efforts toward routine oral hygiene maintenance are needed to improve oral health and minimize the risks of peri-implant diseases in populations.

Cardiomyocyte differentiation of mesenchymal stem cells from bone marrow: new regulators and its implications

In the past years, cardiac mortality has decreased, but cardiac diseases are still responsible for millions of deaths every year worldwide. Bone-marrow mesenchymal stem cells (BMSCs) transplantation may be a promising therapeutic strategy because of its capacity to differentiate into cardiac cells. Current research indicates that chemical substances, microRNAs, and cytokines have biological functions that regulate the cardiomyocytes differentiation of BMSCs. In this review, we chiefly summarize the regulatory factors that induce BMSCs to differentiate into cardiomyocytes.