Single Flap Approach With and Without Guided Tissue Regeneration and a Hydroxyapatite Biomaterial in the Management of Intraosseous Periodontal Defects

Osteoconductivity of Complex Biomaterials Assayed by Fluorescent-Engineered Osteoblast-like Cells

Biomaterials employed for the bone regeneration can be assayed for specific features such as osteoconductivity and gene expression. In this study, the composite HA/collagen/chondroitin-sulfate biomaterial was investigated using an engineered human cell line, named Saos-eGFP. This cell line, a green fluorescent engineered human osteoblast-like cell, was employed as a cellular model for the in vitro study of biomaterial characteristics. The cytotoxicity was indirectly evaluated by fluorescence detection, osteoconductivity was assayed both by fluorescence and electron microscope analysis as well as cell morphology, whereas the RT-PCR technique was employed to assay gene expression. Saos-eGFP cells viability detection after 24 and 96 h of incubation showed that biomaterial enables the adhesion and proliferation of seeded cells as well as that of the plastic surface, the control. Fluorescence and scanning electron microscopy (SEM) analyses indicated that Saos-eGFP cells were homogeneously distributed on the HA granule surfaces, exhibiting cytoplasmic bridges, and were localized on the collagen-chondroitin sulfate extra-cellular matrix. An expression analysis of specific genes encoding for differentiation markers, showed that biomaterial assayed did not alter the osteogenic pathway of the Saos-eGFP cell line. Our assays confirm the cytocompatibility of this biomaterial, suggesting an osteoconductive capacity mediated by its chemical contents. We showed that the Saos-eGFP cellular model is suitable for in vitro biomaterial assays, and more specifically for assessing osteoconductivity. This result suggests that the cytocompatibility and osteoconductive features of the biomaterial assayed as bone substitute, could have a positive downstream effect on implant osteo-integration.

Minimally Invasive Treatment of Infrabony Periodontal Defects Using Dual-Wavelength Laser Therapy

Introduction. Surgical management of infrabony defects is an invasive procedure, frequently requiring the use of adjunctive material such as grafts or biologics, which is time-consuming and associated with expense and morbidity to the patient. Lasers in periodontal regeneration have been reported in the literature, with each wavelength having potential benefits through different laser-tissue interactions. The purpose of this case series was to assess the efficacy of a new dual-wavelength protocol in the management of infrabony defects. Materials and Methods. 32 defects (one in each patient) were treated using ultrasonic debridement, followed by flapless application of Erbium, Chromium:Yttrium, Scandium, Gallium, Garnet (Er,Cr:YSGG) laser (wavelength 2780 nm), and final application of diode laser (wavelength 940 nm). Pocket depths (PD) were measured after 6 months and repeat radiographs taken after one year. Results. The mean baseline PD was 8.8 mm (range 6–15 mm) and 6 months later was 2.4 mm (range 2–4 mm), with mean PD reduction being 6.4 ± 1.7 mm (range 3–12 mm). There was a significant gain in relative linear bone height (apical extent of bone), with mean percentage bone fill of 39.7 ± 41.2% and 53% of sites showing at least 40% infill of bone. Conclusion. The results compare favourably with traditional surgery and require further validation through randomised clinical controlled trials.

The Effect of an Er,Cr:YSGG Laser in the Management of Intrabony Defects Associated with Chronic Periodontitis Using Minimally Invasive Closed Flap Surgery. A Case Series

Aims: This is an extended case series of patients treated with an Erbium, Chromium: Yttrium Scandium Gallium Garnet (Er,Cr:YSGG) laser as an adjunct to scaling for the management of intrabony defects. Materials & methods: 46 patients with 79 angular intrabony defects associated with pocket depths of >5mm, and a mean age of 53 ± 9 years presenting with chronic periodontitis were included in the analysis. All patients underwent a localized minimally invasive closed flap surgery utilizing Er,Cr:YSGG laser therapy. Final radiographs and pocket depths were compared to pretreatment measurements with a time period of 8 ± 3 months. Results: Treatment resulted in significant overall pocket depth reduction. The mean pre-op probing depth was 8.1 ± 1.9mm, reducing to 2.4 ± 0.9mm post-treatment. Bony infill of the defects was visible radiographically and there was an increase in overall radiographic coronal osseous height compared to a pre-treatment baseline. Radiographs of 15 of the defects were available for further measurements after >12 months, and showed in these sites there was a significant reduction in intrabony defect depth, but no change in suprabony bone height. 9 of the 15 sites showed 50% or more, bony infill of the intrabony defect. Conclusions: The results demonstrate that the utilization of an Er,Cr:YSGG laser in a closed flap approach with chronic periodontitis may be of significant clinical benefit. Further studies using this laser surgical protocol are required to test these observations in well-designed randomized controlled trials.

Minimally Invasive Surgery Combined with Regenerative Biomaterials in Treating Intra-Bony Defects: A Meta-Analysis

Background

With the popularity of minimally invasive surgery (MIS) in periodontics, numerous publications have evaluated the benefits of MIS with or without various regenerative biomaterials in the treatment of periodontal intra-bony defects. However, it is unclear if it is necessary to use biomaterials in MIS. Thus, we conducted a meta-analysis of randomized clinical trials in patients with intra-bony defects to compare the clinical outcomes of MIS with regenerative biomaterials for MIS alone.

Methods

The authors retrieved English publications on relevant studies from Cochrane CENTRAL, PubMed, Medline, Embase, Clinical Evidence, and ClinicalTrails.gov (up to June 30, 2015). The main clinical outcomes were the reduction of probing pocket depths (PPDs), gain of clinical attachment level (CAL), recession of gingival margin (REC) and radiographic bone fill. Review Manager 5.2 (Cochrane Collaboration, Oxford, England) was used to calculate the heterogeneity and mean differences of the main clinical outcomes.

Results

In total, 464 studies in the literature were identified but only four were ultimately feasible. The results showed no significant difference regarding CAL gain (P = 0.32) and PPD reduction (P = 0.40) as well as REC increase (P = 0.81) and radiographic bone fill (P = 0.64) between the MIS plus biomaterials group and the MIS alone group.

Conclusions

The meta-analysis suggested no significant difference in treatment of intra-bony defects between the MIS plus biomaterials group and the MIS alone group, indicating that it is important to take costs and benefits into consideration when a decision is made about a therapeutic approach. There needs to be an in-depth exploration of the induction of intrinsic tissue healing of MIS without biomaterials to achieve optimal outcomes.

Clinical evaluation of the regenerative potential of EMD and NanoHA in periodontal infrabony defects: a 2-year follow-up

INTRODUCTION

The aim of this retrospective study was to compare the clinical efficacy of four different surgical techniques in promoting periodontal regeneration in patients with infrabony defects: open flap debridement, application of enamel matrix derivatives (EMD), nanohydroxyapatite (nanoHA) application, and combined nanoHA and EMD application. Probing attachment level (PAL), pocket depth (PD), and position of gingival margin at completion of therapy (REC) were measured.

MATERIALS AND METHODS

Data were collected from 64 healthy patients (34 women and 30 men, mean age 37,7 years). Clinical indices were measured by a calibrated examiner at baseline and at 12, 18, and 24 months. The values obtained for each treatment were compared using nonparametric tests.

RESULTS

All treatments resulted in a tendency toward PD reduction over time, with improvements in REC and PAL. The differences in PD, REC, and PAL values at baseline compared with values after 12, 18, and 24 months were statistically significant for all treatments. Statistically significant differences in PAL and PD were detected between nanoHA and nanoHA + EMD at 12, 18, and 24 months.

CONCLUSION

In this study, EMD and nanoHA used together in patients with infrabony periodontal lesions had better clinical efficacy than nanoHA alone, EMD alone, or open flap debridement.

Periodontal regeneration - intrabony defects: a systematic review from the AAP Regeneration Workshop

BACKGROUND

Previous systematic reviews of periodontal regeneration with bone replacement grafts and guided tissue regeneration (GTR) were defined as state of the art for clinical periodontal regeneration as of 2002.

METHODS

The purpose of this systematic review is to update those consensus reports by reviewing periodontal regeneration approaches developed for the correction of intrabony defects with the focus on patient-, tooth-, and site-centered factors, surgical approaches, surgical determinants, and biologics. This review adheres to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for systematic reviews. A computerized search of the PubMed and Cochrane databases was performed to evaluate the clinically available regenerative approaches for intrabony defects. The search included screening of original reports, review articles, and reference lists of retrieved articles and hand searches of selected journals. All searches were focused on clinically available regenerative approaches with histologic evidence of periodontal regeneration in humans published in English. For topics in which the literature is lacking, non-randomized observational and experimental animal model studies were used. Therapeutic endpoints examined included changes in clinical attachment level, changes in bone level/fill, and probing depth. For purposes of analysis, change in bone fill was used as the primary outcome measure, except in cases in which this information was not available. The SORT (Strength of Recommendation Taxonomy) grading scale was used in evaluating the body of knowledge.

RESULTS

1) Fifty-eight studies provided data on patient, tooth, and surgical-site considerations in the treatment of intrabony defects. 2) Forty-five controlled studies provided outcome analysis on the use of biologics for the treatment of intrabony defects.

CONCLUSIONS

1) Biologics (enamel matrix derivative and recombinant human platelet-derived growth factor-BB plus β-tricalcium phosphate) are generally comparable with demineralized freeze-dried bone allograft and GTR and superior to open flap debridement procedures in improving clinical parameters in the treatment of intrabony defects. 2) Histologic evidence of regeneration has been demonstrated with laser therapy; however, data are limited on clinical predictability and effectiveness. 3) Clinical outcomes appear most appreciably influenced by patient behaviors and surgical approach rather than by tooth and defect characteristics. 4) Long-term studies indicate that improvements in clinical parameters are maintainable up to 10 years, even in severely compromised teeth, consistent with a favorable/good long-term prognosis.

Regenerative periodontal therapy: 30 years of lessons learned and unlearned

In this review, we reflect upon advances and hindrances encountered over the last three decades in the development of strategies for periodontal regeneration. In this soul-searching pursuit we focus on revisiting lessons learned that should guide us in the quest for the reconstruction of the lost periodontium. We also examine beliefs and traditions that should be unlearned so that we can continue to advance the field. This learned/unlearned body of knowledge is consolidated into core principles to help us to develop new therapeutic approaches to benefit our patients and ultimately our society.

Synthesis methods for nanosized hydroxyapatite with diverse structures

Hydroxyapatite (HAp) is the major mineral constituent of vertebrate bones and teeth. It has been well documented that HAp nanoparticles can significantly increase the biocompatibility and bioactivity of man-made biomaterials. Over the past decade, HAp nanoparticles have therefore increasingly been in demand, and extensive efforts have been devoted to develop many synthetic routes, involving both scientifically and economically new features. Several investigations have also been made to determine how critical properties of HAp can be effectively controlled by varying the processing parameters. With such a wide variety of methods for the preparation of HAp nanoparticles, choosing a specific procedure to synthesize a well-defined powder can be laborious; accordingly, in the present review, we have summarized all the available information on the preparation methodologies of HAp, and highlighted the inherent advantages and disadvantages involved in each method. This article is focused on nanosized HAp, although recent articles on microsized particles, especially those assembled from nanoparticles and/or nanocrystals, have also been reviewed for comparison. We have also provided several scientific figures and discussed a number of critical issues and challenges which require further research and development.

Absorbable Collagen Membranes for Periodontal Regeneration

Guided tissue regeneration (GTR) with bioabsorbable collagen membranes (CM) is commonly used for the treatment of periodontal defects. The objective of this systematic review of randomized clinical trials was to assess the clinical efficacy of GTR procedures with CM, with or without bone substitutes, in periodontal infrabony defects compared with that of open flap debridement (OFD) alone. Primary outcomes were tooth loss and gain in clinical attachment level (CAL). Screening of records, data extraction, and risk-of-bias assessments were performed by two reviewers. Weighted mean differences were estimated by random effects meta-analysis. We included 21 reports on 17 trials. Risk of bias was generally high. No data were available for the primary outcome tooth loss. The summary treatment effect for change in CAL for GTR with CM compared with OFD was 1.58 mm (95% CI, 1.27 to 1.88). Despite large between-trial heterogeneity (I2 = 75%, p < .001), all trials favored GTR over OFD. No differences in treatment effects were detected between trials of GTR with CM alone and trials of GTR with CM in combination with bone substitutes ( p for interaction, .31). GTR with CM, with or without substitutes, may result in improved clinical outcomes compared with those achieved with OFD alone. Our findings support GTR with CM for the treatment of infrabony periodontal defects.

Surgical Approaches Based on Biological Objectives: GTR versus GBR Techniques

Guided tissue regenerative (GTR) therapies are performed to regenerate the previously lost tooth supporting structure, thus maintaining the aesthetics and masticatory function of the available dentition. Alveolar ridge augmentation procedures (GBR) intend to regain the alveolar bone lost following tooth extraction and/or periodontal disease. Several biomaterials and surgical approaches have been proposed. In this paper we report biomaterials and surgical techniques used for periodontal and bone regenerative procedures. Particular attention will be adopted to highlight the biological basis for the different therapeutic approaches.

Calcium orthophosphates in dentistry

Dental caries, also known as tooth decay or a cavity, remains a major public health problem in the most communities even though the prevalence of disease has decreased since the introduction of fluorides for dental care. Therefore, biomaterials to fill dental defects appear to be necessary to fulfill customers' needs regarding the properties and the processing of the products. Bioceramics and glass-ceramics are widely used for these purposes, as dental inlays, onlays, veneers, crowns or bridges. Calcium orthophosphates belong to bioceramics but they have some specific advantages over other types of bioceramics due to a chemical similarity to the inorganic part of both human and mammalian bones and teeth. Therefore, calcium orthophosphates (both alone and as components of various formulations) are used in dentistry as both dental fillers and implantable scaffolds. This review provides brief information on calcium orthophosphates and describes in details current state-of-the-art on their applications in dentistry and dentistry-related fields. Among the recognized dental specialties, calcium orthophosphates are most frequently used in periodontics; however, the majority of the publications on calcium orthophosphates in dentistry are devoted to unspecified "dental" fields.