Histological evaluation of human intrabony periodontal defects treated with an unsintered nanocrystalline hydroxyapatite paste

Influence of alloplastic materials, biologics, and their combinations, along with defect characteristics, on short-term intrabony defect surgical treatment outcomes: a systematic review and network meta-analysis

BACKGROUND

Treating periodontal intrabony defects remains challenging, alloplast materials and biologics are increasingly utilized to improve regeneration outcomes. However, comparative efficacy on alloplast materials remains limited. This study aimed to evaluate the effectiveness of alloplastic materials, both alone and combined with biologics, in treating periodontal defects.

METHODS

A systematic search of PubMed, Scopus, and CENTRAL identified 74 eligible randomized controlled trials. Meta-analysis assessed data heterogeneity based on defect depth and morphology, classifying defects by wall configuration. Network meta-analysis compared clinical attachment level (CAL) gain, probing depth (PD) reduction, and radiographic linear bone (RLB) gain up to 12 months. Risk of bias was evaluated using the Cochrane Risk of Bias 2 tool, and confidence in network meta-analysis was graded using CINeMA.

RESULTS

Defect depth and morphology significantly impacted heterogeneity outcomes at 6 months, but by 12 months, differences across treatments were less significant. Biphasic calcium phosphate (BCP) and nanocrystalline hydroxyapatite (nHA) showed notable improvements in CAL gain, PD reduction, and RLB gain. Combining nHA with platelet-rich fibrin (PRF) outperformed open flap debridement (mean differences at 6 months for CAL gain: 1.37 mm, PD reduction: 1.52 mm and RLB gain: 1.39 mm). SUCRA ranked bioglass and BCP highest for single treatments, while bioglass with platelet-rich plasma and nHA + PRF excelled among combinations.

CONCLUSIONS

Alloplastic materials, particularly BCP and nHA, significantly enhance periodontal treatment outcomes, especially when combined with biologics like PRF. Defect depth and morphology influence treatment efficacy at 6 months, though by 12 months, treatment outcomes converge, underscoring the value of early, tailored strategies in periodontal therapy.

TRIAL REGISTRATION

Not applicable.

Systematic Review Regarding the Clinical Implications of Allograft and Alloplastic Bone Substituents Used for Periodontal Regenerative Therapy

Background/Objectives: Regenerative periodontal therapy is a treatment method that focuses on restoring the periodontium affected by chronic inflammatory disease or injury. It involves using different biomaterials and techniques to completely restore the periodontal structures. The main objective was to identify and critically evaluate relevant studies comparing the clinical efficacy of allograft and alloplastic materials in regenerative periodontal therapy. Methods: For evaluation, a systematic review based on PRISMA guidelines was conducted. Data were extracted using only specific types of study designs, which included randomized controlled trials, cohort studies, and case-control studies. Target patients with periodontal disease or periodontal lesions undergoing periodontal therapy using allograft or alloplastic materials were selected. Periodontal parameters such as clinical attachment level, probing pocket depth, radiographic bone fill, or patient-reported outcomes were analyzed. Results: The results showed that allograft and alloplastic materials offered reduced pocket depth, a gain in clinical attachment, and bone repairment. The variation observed indicated that allografts showed a slightly more significant clinical attachment gain and a superior bone fill than alloplastic ones, suggesting that allografts enhance osteogenesis and provide a greater capacity for repair in periodontal defects. Conclusions: The results of the present study suggest that allograft and alloplastic materials offered reduced pocket depth, a gain in clinical attachment, and bone repairment, with both methods having similar clinical efficacy.

From Basic Science to Clinical Practice: A Review of Current Periodontal/Mucogingival Regenerative Biomaterials

Periodontitis is a dysbiosis-driven inflammatory disease affecting the tooth-supporting tissues, characterized by their progressive resorption, which can ultimately lead to tooth loss. A step-wise therapeutic approach is employed for periodontitis. After an initial behavioral and non-surgical phase, intra-bony or furcation defects may be amenable to regenerative procedures. This review discusses the regenerative technologies employed for periodontal regeneration, highlighting the current limitations and future research areas. The search, performed on the MEDLINE database, has identified the available biomaterials, including biologicals (autologous platelet concentrates, hydrogels), bone grafts (pure or putty), and membranes. Biologicals and bone grafts have been critically analyzed in terms of composition, mechanism of action, and clinical applications. Although a certain degree of periodontal regeneration is predictable in intra-bony and class II furcation defects, complete defect closure is hardly achieved. Moreover, treating class III furcation defects remains challenging. The key properties required for functional regeneration are discussed, and none of the commercially available biomaterials possess all the ideal characteristics. Therefore, research is needed to promote the advancement of more effective and targeted regenerative therapies for periodontitis. Lastly, improving the design and reporting of clinical studies is suggested by strictly adhering to the Consolidated Standards of Reporting Trials (CONSORT) 2010 statement.

Preclinical evaluation of a new synthetic carbonate apatite bone substitute on periodontal regeneration in intrabony defects

OBJECTIVE

To evaluate the potential of a novel synthetic carbonate apatite bone substitute (CO3 Ap-BS) on periodontal regeneration.

BACKGROUND

The use of various synthetic bone substitutes as a monotherapy for periodontal regeneration mainly results in a reparative healing pattern. Since xenografts or allografts are not always accepted by patients for various reasons, a synthetic alternative would be desirable.

METHODS

Acute-type 3-wall intrabony defects were surgically created in 4 female beagle dogs. Defects were randomly allocated and filled with CO3 Ap-BS (test) and deproteinized bovine bone mineral (DBBM) or left empty (control). After 8 weeks, the retrieved specimens were scanned by micro-CT, and the percentages of new bone, bone substitute, and soft tissues were evaluated. Thereafter, the tissues were histologically and histometrically analyzed.

RESULTS

Healing was uneventful in all animals, and defects were present without any signs of adverse events. Formation of periodontal ligament and cementum occurred to varying extent in all groups without statistically significant differences between the groups. Residues of both bone substitutes were still present and showed integration into new bone. Histometry and micro-CT revealed that the total mineralized area or volume was higher with the use of CO3 Ap-BS compared to control (66.06 ± 9.34%, 36.11 ± 6.40%; p = .014, or 69.74 ± 2.95%, 42.68 ± 8.68%; p = .014). The percentage of bone substitute surface covered by new bone was higher for CO3 Ap-BS (47.22 ± 3.96%) than for DBBM (16.69 ± 5.66, p = .114).

CONCLUSIONS

CO3 Ap-BS and DBBM demonstrated similar effects on periodontal regeneration. However, away from the root surface, more new bone, total mineralized area/volume, and higher osteoconductivity were observed for the CO3 Ap-BS group compared to the DBBM group. These findings point to the potential of CO3 Ap-BS for periodontal and bone regeneration.

Nanocrystalline hydroxyapatite in periodontal bone regeneration: A systematic review

Background

Periodontal diseases when persistent, results in periodontal pockets, attachment loss and progressive destruction of the alveolar bone. Grafting periodontal bone defects with bone substitute biomaterials has proven clinical success for accomplishing reconstruction of lost attachment apparatus, especially in deep intra-bony defects. Nanoparticles (NPs) have been considered indispensable in the future of health sciences and NP based alloplastic graft materials such as nanocrystalline hydroxyapatite (NCHA) hold great promise for regeneration of periodontal defects. Therefore the aim of this review is to evaluate the role of NCHA as an effective substitute for periodontal bone regeneration.

Material & methods

Popular scientific databases such as PubMed (Medline), Cochrane database of clinical trials, Scopus (Elsevier), Web of science (Clarivate Analytics) and Google Scholar, were searched. The literature search was restricted to published reports in English, between January 2000 and December 2021. Database search returned 1227 results which were screened based on title, author names and publication dates.

Results

Data from the 14 included studies were reviewed and tabulated. In the present review, all the studies reported using commercially available NCHA for periodontal bone regeneration.

Conclusion

NCHA is a suitable bone substitute material for periodontal bone regeneration, with outcomes comparable to that of conventionally used graft materials such as bovine xenograft and other synthetic alloplastic materials. While grafting with NCHA in intrabony periodontal defects, after any form of periodontal flap surgery or debridement, significantly improves bone regeneration by 6 months, addition of adjuncts like EMD and PRF further enhance the outcomes.

Biomaterials for Periodontal Regeneration

As a widespread chronical disease, periodontitis progressively destroys tooth-supporting structures (periodontium) and eventually leads to tooth loss. Therefore, regeneration of damaged/lost periodontal tissues has been a major subject in periodontal research. During periodontal tissue regeneration, biomaterials play pivotal roles in improving the outcome of the periodontal therapy. With the advancement of biomaterial science and engineering in recent years, new biomimetic materials and scaffolding fabrication technologies have been proposed for periodontal tissue regeneration. This article summarizes recent progress in periodontal tissue regeneration from a biomaterial perspective. First, various guide tissue regeneration/guide bone regeneration membranes and grafting biomaterials for periodontal tissue regeneration are overviewed. Next, the recent development of multifunctional scaffolding biomaterials for alveolar bone/periodontal ligament/cementum regeneration is summarized. Finally, clinical care points and perspectives on the use of biomimetic scaffolding materials to reconstruct the hierarchical periodontal tissues are provided.

Comparison of periodontal wound healing/regeneration by recombinant human fibroblast growth factor-2 combined with β-tricalcium phosphate, carbonate apatite, or deproteinized bovine bone mineral in a canine one-wall intra-bony defect model

AIM

To evaluate periodontal wound healing/regeneration of one-wall intra-bony defects treated with recombinant human fibroblast growth factor-2 (rhFGF-2) and beta-tricalcium phosphate (β-TCP), carbonate apatite (CO₃ Ap), or deproteinized bovine bone mineral (DBBM) in dogs.

MATERIALS AND METHODS

The stability of rhFGF-2 adsorbed onto the bone substitutes was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA). One-wall intra-bony defects (5 × 5 × 5 mm) created in five adult male beagle dogs were treated with rhFGF-2 alone (rhFGF-2), rhFGF-2 with β-TCP (rhFGF-2/β-TCP), rhFGF-2 with CO₃ Ap (rhFGF-2/CO₃ Ap), or rhFGF-2 with DBBM (rhFGF-2/DBBM). Histological outcomes (e.g., linear length of new cementum adjacent to the newly formed bone with inserting collagen fibres [NA] as the primary outcome) were evaluated at 10 weeks post surgery.

RESULTS

Significantly higher amount of rhFGF-2 was adsorbed onto CO₃ Ap compared with β-TCP. Among the treatment groups, the rhFGF-2/DBBM group showed the highest amount of periodontal tissue regeneration. The rhFGF-2/DBBM group showed significantly greater formation of NA (3.22 ± 0.40 mm) compared with rhFGF-2 (1.17 ± 1.00 mm, p < .01) group. Additionally, new bone area in the rhFGF-2/DBBM group (9.78 ± 2.30 mm² ) was significantly higher than that in the rhFGF-2 (5.08 ± 1.26 mm² , p < .01), rhFGF-2/β-TCP (5.91 ± 1.27 mm² , p < .05), and rhFGF-2/CO₃ Ap (6.51 ± 1.49 mm² , p < .05) groups. Slight ankylosis was found in the rhFGF-2/β-TCP (1/9 sites), rhFGF-2/CO₃ Ap (3/10 sites), and rhFGF-2/DBBM (1/9 sites) groups.

CONCLUSIONS

Within their limitations, the present data indicate that DBBM seems to be a suitable carrier for rhFGF-2 and that rhFGF-2/DBBM treatment promotes favourable periodontal regeneration compared with rhFGF-2, rhFGF-2/β-TCP, and rhFGF-2/CO₃ Ap treatments in one-wall intra-bony defects.

Nanocrystalline hydroxyapatite in regeneration of periodontal intrabony defects: A systematic review and meta-analysis

BACKGROUND

Alveolar bone loss and mobility of teeth is commonly observed in periodontitis patients. Regeneration of periodontal intrabony defects is indicated to restore the lost bone and periodontal tissues. The aim of the present study was to evaluate the clinical outcomes of periodontal intrabony lesions by using nanocrystalline hydroxyapatite (NHA) graft and comparing it with open flap debridement (OFD) alone.

MATERIALS AND METHODS

The eligibility criteria encompassed randomized (RCTs) and controlled clinical trials (CCTs). Weighted mean differences were calculated for clinical attachment level (CAL) gain, probing pocket depth (PPD) reduction and gingival recession (REC) change, demonstrated as forest plots. The revised Cochrane Risk of Bias tool for randomized trials (RoB2) and Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) tool were used for quality assessment of RCTs and non-randomized trials respectively.

RESULTS

From 22 full-text articles identified, three RCTs, one CCT and one retrospective follow-up of RCT were included. All the five papers comprised the quantitative evaluation. The use of NHA graft provided additional CAL gain of 0.96 mm (p = 0.0009) and PPD reduction of 0.97 mm (p < 0.00001) when compared to OFD alone. However, in terms of REC changes, no considerable benefits of NHA graft were demonstrated than OFD alone (p = 0.48).

CONCLUSIONS

The bioactive NHA graft showed promising results clinically in regenerative periodontology and can be considered for the management of periodontal intrabony defects. The use of NHA graft considerably provided better clinical outcomes in intrabony defects compared to using the OFD alone. Future research investigating NHA graft against other regenerative materials including specific BGs, at longer follow-up periods and bigger sample sizes and in furcation defects warranted.

Comparing Nanohydroxyapatite Graft and Other Bone Grafts in the Repair of Periodontal Infrabony Lesions: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare the results of periodontal infrabony lesions treated using nanohydroxyapatite (NcHA) graft with other bone grafts (BGs).

METHODS

Four electronic databases were searched including PubMed (NLM), Embase (Ovid), Medline, and Dentistry and Oral Sciences (EBSCO). The inclusion criteria included randomised controlled clinical trials (RCTs) and controlled clinical trials (CCTs). The clinical results of NcHA were compared with other BGs. For clinical attachment level (CAL) gain, probing pocket depth (PPD) decrease, and gingival recession (REC) change, weighted averages and forest plots were computed.

RESULTS

Seven RCTs fulfilled the selection criteria that were included. When NcHA was compared to other BGs, no clinically significant differences were found in terms of each outcome assessed, except the REC change for synthetic BGs as compared to NcHA.

CONCLUSIONS

The use of an NcHA graft showed equivalent results compared to other types of BGs. To further validate these findings, future studies are required to compare the NcHA and various BGs over longer time periods and in furcation deficiencies.

Recombinant Human Derived Growth and Differentiating Factors in treatment of periodontal intrabony defects: Systematic review and network meta-analysis

The introduction of recombinant human growth and differentiation factors (rhGFs) for intrabony defects regeneration has represented a considerable breakthrough in recent years. However, they have been used in different concentrations, doses and combined with various scaffolds, and there is no evidence on which the most effective formulation for periodontal regeneration is. Therefore, we aimed to evaluate and rank the various formulations of such bioactive agents through network meta-analysis of clinical studies. The protocol registration was done on PROSPERO with registration ID CRD42020213753. To report NMA, we followed PRISMA guidelines and searched PUBMED, Embase, Web of Science and Cochrane Central electronic databases. Studies were screened based on specific inclusion criteria. Primary outcomes extracted from included studies were the most common indexes for periodontal regeneration (PPD, CAL, %bone filling). The NMA analysis included network plots, contribution plots, inconsistency plots (if eligible to form the loop), predictive interval plots, SUCRA rankings and multidimensional scale ranking (MDS) plots. SUCRA would demonstrate the rankings of multiple competing bioactive agents based on their best performance. Twelve clinical studies for qualitative and quantitative analysis were considered. Network meta-analysis found that rhFGF + hydroxyapatite was ranked highest in PPD and CAL outcome. rhPDGF-BB+β-tricalcium phosphate was ranked highest in the percentage of bone filling. In addition, all bioactive agents performed better than control groups without rhGFs. Despite clear benefits deriving from rhGFs for periodontal regeneration, the present results should be interpreted with caution due to several confounding factors affecting the outcome. Nevertheless, further well designed randomized clinical trials will allow establishing guidelines for an appropriate indication of the use of rhGFs.

Current and Advanced Nanomaterials in Dentistry as Regeneration Agents: An Update

In modern dentistry, nanomaterials have strengthened their foothold among tissue engineering strategies for treating bone and dental defects due to a variety of reasons, including trauma and tumors. Besides their finest physiochemical features, the biomimetic characteristics of nanomaterials promote cell growth and stimulate tissue regeneration. The single units of these chemical substances are small-sized particles, usually between 1 to 100 nm, in an unbound state. This unbound state allows particles to constitute aggregates with one or more external dimensions and provide a high surface area. Nanomaterials have brought advances in regenerative dentistry from the laboratory to clinical practice. They are particularly used for creating novel biomimetic nanostructures for cell regeneration, targeted treatment, diagnostics, imaging, and the production of dental materials. In regenerative dentistry, nanostructured matrices and scaffolds help control cell differentiation better. Nanomaterials recapitulate the natural dental architecture and structure and form functional tissues better compared to the conventional autologous and allogenic tissues or alloplastic materials. The reason is that novel nanostructures provide an improved platform for supporting and regulating cell proliferation, differentiation, and migration. In restorative dentistry, nanomaterials are widely used in constructing nanocomposite resins, bonding agents, endodontic sealants, coating materials, and bioceramics. They are also used for making daily dental hygiene products such as mouth rinses. The present article classifies nanostructures and nanocarriers in addition to reviewing their design and applications for bone and dental regeneration.

A Clinical and Radiographic Evaluation of the Efficacy of Nanohydroxyapatite (Sybograf™) versus Bioactive Calcium Phosphosilicate Putty (Novabone®) in the Treatment of Human Periodontal Infrabony Defects: A Randomized Clinical Trial

Aim:

The aim of this study is to compare and to evaluate clinically and radiographically the bone regeneration and the amount of bone fill (BL) between nanocrystalline hydroxyapatite (Nc-HA) (Sybograf™) and bioactive synthetic NovaBone Putty in the treatment of intrabony component of periodontal osseous defects.

Materials and Methods:

Twenty sites in 20 patients, within the age range of 25–55 years, showing intrabony defects were selected and divided into Group I (Nc-HA) and Group II (Bioactive synthetic NovaBone Putty). All the selected sites were assessed with the clinical and radiographic parameters such as plaque index, gingival index, sulcus bleeding index, probing pocket depth, clinical attachment level, gingival recession, and radiographic BL. All the clinical and radiographic parameter values obtained at different intervals (baseline, 3, and 6 and 9 months) were subjected to statistical analysis.

Results:

A statistically significant reduction in pocket depth of 4.400 ± 0.843 mm (Group I), 3.800 ± 0.789 mm (Group II) and gain in clinical attachment level of 6.2 mm (Group I), 5.9 mm (Group II) were recorded at the end of the study. A slight increase in gingival recession was observed. The mean percentage changes in the amount of radiographic BL of Group II and Group I were significant, However, when compared between the groups, there is no significant difference in BL observed.

Conclusion:

Both the graft materials appear to have nearly comparable effects, with nanocrystalline hydroxyapatite (Sybograf™), displaying slightly superior effect over bioactive glass especially in relation to clinical parameters. However, long-term, controlled clinical trials are required to confirm these findings.

The paradigm shift for drug delivery systems for oral and maxillofacial implants

Along with the development of nanotechnological strategies for biomaterials associated with the prevention of infections, a myriad of clinically unproven techniques have been described to date. In this work, the aim was to perform a critical analysis of the literature available concerning antibacterial biomaterials for oral implantology and to provide a practical derivation for such a purpose. As anti-adhesive strategies may affect osseointegration, they should no longer be recommended for inclusion in this class of biomaterials, despite promising results in biomedical engineering for other, non-bone load bearing organs. Targeted, antibacterial drug delivery is most likely desirable in the case of intraosseous implants. Interfering factors such as the oral cavity environment, saliva, the bacterial microbiome, as well as, the characteristics of the alveolar mucosa and peri-implant space must be taken into account when calculating the local pharmacokinetics for antibacterial coatings. Effective release is crucial for tailoring antibacterial implant longevity providing minimal inhibitory concentration (MIC) for the desired amount of time, which for oral implants, should be at least the cumulative time for the osseointegration period and functional loading period within the tissues. These parameters may differ between the implant type and its anatomical site. Also, the functional drug concentration in the peri-implant space should be calculated as the amount of the drug released from the implant surface including the concentration of the drug inactivated by biological fluids of the peri-implant space or saliva flow throughout the effective release time.

The use of hydroxyapatite bone substitute grafting for alveolar ridge preservation, sinus augmentation, and periodontal bone defect: A systematic review

OBJECTIVES

We determined and structurally analyzed the reported effect of hydroxyapatite (HA) bone substitute on alveolar bone regeneration. To the best of our knowledge, no systematic reviews have previously reported the bone regenerative effect of the HA bone substitute.

MATERIALS AND METHODS

A literature search was performed for articles published up to August 2015 using MEDLINE with the search terms "hydroxyapatite," "bone regeneration," and "alveolar bone" as well as their known synonyms. The inclusion criteria were set up for human trials with at least five patients. The literature search, eligible article selection, and data extraction were independently performed by two readers, and their agreement was reported by κ value.

RESULTS

Of the 504 studies found using the MEDLINE literature search, 241 were included for further steps (inter-reader agreement, κ = 0.968). Abstract screening yielded 74 studies (κ = 0.910), with 42 completely fulfilling the inclusion criteria (κ = 0.864). In a final step, 42 studies were further analyzed, with 17 and 25 studies with and without statistical analysis, respectively. The 17 studies reporting similar outcome measures were compared using the calculated 95% confidence intervals. The effect of HA on ridge preservation could not be evaluated.

CONCLUSIONS

The use of the HA bone substitute interfered with the normal healing process, with significant differences found for sinus augmentation but not for periodontal bone defects. Thus, a bone substitute with optimal bone regenerative properties for alveolar ridge or socket preservation, sinus augmentation, and periodontal bony defect should be developed.

Nanomaterials in dentistry: a cornerstone or a black box?

Aim: The studies on tooth structure provided basis for nanotechnology-based dental treatment approaches known as nanodentistry which aims at detection and treatment of oral pathologies, such as dental caries and periodontal diseases, insufficiently being treated by conventional materials or drugs. This review aims at defining the role of nanodentistry in the medical area, its potential and hazards. Materials & methods: To validate these issues, current literature on nanomaterials for dental applications was critically reviewed. Results: Nanomaterials for teeth restoration, bone regeneration and oral implantology exhibit better mechanical properties and provide more efficient esthetic outcome. However, still little is known about influence of long-term function of such biomaterials in the living organism. Conclusion: As application of nanomaterials in industry and medical-related sciences is still expanding, more information is needed on how such nano-dental materials may interfere with oral cavity, GI tract and general health.

Assessment of periodontal bone level revisited: a controlled study on the diagnostic accuracy of clinical evaluation methods and intra-oral radiography

OBJECTIVES

The accuracy of analogue and especially digital intra-oral radiography in assessing interdental bone level needs further documentation. The aim of this study was to compare clinical and radiographic bone level assessment to intra-surgical bone level registration (1) and to identify the clinical variables rendering interdental bone level assessment inaccurate (2).

MATERIALS AND METHODS

The study sample included 49 interdental sites in 17 periodontitis patients. Evaluation methods included vertical relative probing attachment level (RAL-V), analogue and digital intra-oral radiography and bone sounding without and with flap elevation. The latter was considered the true bone level. Five examiners evaluated all radiographs.

RESULTS

Significant underestimation of the true bone level was observed for all evaluation methods pointing to 2.7 mm on average for analogue radiography, 2.5 mm for digital radiography, 1.8 mm for RAL-V and 0.6 mm for bone sounding without flap elevation (p < 0.001). Radiographic underestimation of the true bone level was higher in the (pre)molar region (p ≤ 0.047) and increased with defect depth (p < 0.001). Variation between clinicians was huge (range analogue radiography 2.2-3.2 mm; range digital radiography 2.1-3.0 mm).

CONCLUSION

All evaluation methods significantly underestimated the true bone level. Bone sounding was most accurate, whereas intra-oral radiographs were least accurate. Deep periodontal defects in the (pre)molar region were most underrated by intra-oral radiography.

CLINICAL RELEVANCE

Bone sounding had the highest accuracy in assessing interdental bone level.

Cytocompatibility and biocompatibility of nanostructured carbonated hydroxyapatite spheres for bone repair

Objective

The aim of this study was to investigate the in vitro and in vivo biological responses to nanostructured carbonated hydroxyapatite/calcium alginate (CHA) microspheres used for alveolar bone repair, compared to sintered hydroxyapatite (HA).

Material and Methods

The maxillary central incisors of 45 Wistar rats were extracted, and the dental sockets were filled with HA, CHA, and blood clot (control group) (n=5/period/group). After 7, 21 and 42 days, the samples of bone with the biomaterials were obtained for histological and histomorphometric analysis, and the plasma levels of RANKL and OPG were determined via immunoassay. Statistical analysis was performed by Two-Way ANOVA with post-hoc Tukey test at 95% level of significance.

Results

The CHA and HA microspheres were cytocompatible with both human and murine cells on an in vitro assay. Histological analysis showed the time-dependent increase of newly formed bone in control group characterized by an intense osteoblast activity. In HA and CHA groups, the presence of a slight granulation reaction around the spheres was observed after seven days, which was reduced by the 42^nd day. A considerable amount of newly formed bone was observed surrounding the CHA spheres and the biomaterials particles at 42-day time point compared with HA. Histomorphometric analysis showed a significant increase of newly formed bone in CHA group compared with HA after 21 and 42 days from surgery, moreover, CHA showed almost 2-fold greater biosorption than HA at 42 days (two-way ANOVA, p<0.05) indicating greater biosorption. An increase in the RANKL/OPG ratio was observed in the CHA group on the 7^th day.

Conclusion

CHA spheres were osteoconductive and presented earlier biosorption, inducing early increases in the levels of proteins involved in resorption.

Wound models for periodontal and bone regeneration: the role of biologic research

The ultimate goals of periodontal therapy remain the complete regeneration of those periodontal tissues lost to the destructive inflammatory-immune response, or to trauma, with tissues that possess the same structure and function, and the re-establishment of a sustainable health-promoting biofilm from one characterized by dysbiosis. This volume of Periodontology 2000 discusses the multiple facets of a transition from therapeutic empiricism during the late 1960s, toward regenerative therapies, which is founded on a clearer understanding of the biophysiology of normal structure and function. This introductory article provides an overview on the requirements of appropriate in vitro laboratory models (e.g. cell culture), of preclinical (i.e. animal) models and of human studies for periodontal wound and bone repair. Laboratory studies may provide valuable fundamental insights into basic mechanisms involved in wound repair and regeneration but also suffer from a unidimensional and simplistic approach that does not account for the complexities of the in vivo situation, in which multiple cell types and interactions all contribute to definitive outcomes. Therefore, such laboratory studies require validatory research, employing preclinical models specifically designed to demonstrate proof-of-concept efficacy, preliminary safety and adaptation to human disease scenarios. Small animal models provide the most economic and logistically feasible preliminary approaches but the outcomes do not necessarily translate to larger animal or human models. The advantages and limitations of all periodontal-regeneration models need to be carefully considered when planning investigations to ensure that the optimal design is adopted to answer the specific research question posed. Future challenges lie in the areas of stem cell research, scaffold designs, cell delivery and choice of growth factors, along with research to ensure appropriate gingival coverage in order to prevent gingival recession during the healing phase.

Evaluation of OSSIFI® as Alloplastic Bone Graft Material in Treatment of Periodontal Infrabony Defects

INTRODUCTION

The shift in therapeutic concepts from resection to regeneration has significantly impacted the practice of periodontology. Human studies have revealed that hydroxyapatite bone cement holds great promise as a grafting alloplastic material.

AIMS AND OBJECTIVES

To evaluate the efficacy of OSSIFI(®) (combined beta tricalcium phosphate plus hydroxyapatite) in the treatment of periodontal infrabony defects.

MATERIALS AND METHODS

Ten study subjects were selected and divided into two groups. Group I (PD>7mm) and Group II (PD≤ 7mm). Both Groups I and II were treated by regenerative periodontal surgery using OSSIFI(®) as graft material. Plaque index, gingival index, pocket depth, clinical attachment levels were recorded clinically and bone fill, radiographically, at baseline, three months and six months.

RESULTS AND CONCLUSION

Statistically significant reduction in pocket depth, plaque index, gingival index was seen after six months. There was significant bone fill seen from 3-6months with significant gain in clinical attachment levels.

Biomimetic ceramics for periodontal regeneration in infrabony defects: A systematic review

Biomimetic materials are widely used in the treatment of osseous defects as an alternative to autogenous bone graft. The aim of this article was to review the literature and compare the quality of published articles on biomimetic ceramic material used for periodontal regeneration in the treatment of infrabony defects and to discuss the future direction of research. The bibliographic databases PubMed, Ebsco, and Google Scholar were searched from January 2000 to March 2014 for randomized control trials in which biomimetic ceramic graft material was compared with open flap debridement or in combination with any other regenerative material. To avoid the variability of the search terms, the thesaurus Mesh was used. The primary outcome variable assessed was clinical attachment level (CAL). The screening of eligible studies, assessment of the methodological quality of the trials, and data extraction were performed by two observers independently. Twenty-six articles were identified and included in this systematic review. The primary outcome was CAL. Out of the 26 studies, 24 showed more than 2 mm of CAL gain. The difference in CAL change between test and control groups varied from 1.2 mm to 5.88 mm with respect to different biomaterials/biomimetic materials, which was clinically and statistically significant. Meta-analysis was not done due to heterogeneity in results between studies. Overall, biomaterials were found to be more effective than open flap debridement in improving the attachment levels in intraosseous defects. Future research should aim at increasing the osteoinductive capacity of these biomimetic graft materials.

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.

Clinical outcomes after treatment of periodontal intrabony defects with nanocrystalline hydroxyapatite (Ostim) or enamel matrix derivatives (Emdogain): a randomized controlled clinical trial

Introduction. Periodontitis is an inflammatory process in response to dental biofilm and leads to periodontal tissue destruction. The aim of this study was the comparison of outcomes using either an enamel matrix derivative (EMD) or a nanocrystalline hydroxyapatite (NHA) in regenerative periodontal therapy after 6 and 12 months. Methods. Using a parallel group, prospective randomized study design, we enrolled 19 patients in each group. The primary outcome was bone fill after 12 months. Attachment gain, probing pocket depth (PPD) reduction, and recession were secondary variables. Additionally, early wound healing and adverse events were assessed. Data analysis included test of noninferiority of NHA group (test) compared to EMD group (reference) in bone fill. Differences in means of secondary variables were compared by paired t-test, frequency data by exact χ² test. Results. Both groups showed significant bone fill, reduction of PPD, increase in recession, and gain of attachment after 6 and 12 months. No significant differences between groups were found at any time point. Adverse events were comparable between both groups with a tendency of more complaints in the NHA group. Conclusion. The clinical outcomes were similar in both groups. EMD could have some advantage compared to NHA regarding patients comfort and adverse events. The trial is registered with ClinicalTrials.gov NCT00757159.

Effect of pulverized natural bone mineral on regeneration of three-wall intrabony defects. A preclinical study

AIMS

The objective of this study is to evaluate the effects of a paste-like bone substitute material with easy handling properties and improved mechanical stability on periodontal regeneration of intrabony defects in dogs.

MATERIALS AND METHODS

Mandibular and maxillary first and third premolars were extracted, and three-wall intrabony defects were created on second and fourth premolars. After a healing period of 3 months, acute type defects were filled with a paste-like formulation of deproteinized bovine bone mineral (DBBM) (particle size, 0.125-0.25 mm) in a collagenous carrier matrix (T1), pulverized DBBM (particle size, 0.125-0.25 mm) without the carrier (T2), or Bio-Oss® granules (particle size, 0.25-1.00 mm) as control (C). All defects were covered with a Bio-Gide® membrane. The dogs were sacrificed after 12 weeks, and the specimens were analyzed histologically and histometrically.

RESULTS

Postoperative healing of all defects was uneventful, and no histological signs of inflammation were observed in the augmented and gingival regions. New cementum, new periodontal ligament, and new bone were observed in all three groups. The mean vertical bone gain was 3.26 mm (T1), 3.60 mm (T2), and 3.81 mm (C). That of new cementum was 2.25 mm (T1), 3.88 mm (T2), and 3.53 mm (C). The differences did not reach statistical significance. The DBBM particles were both incorporated in new bone and embedded in immature bone marrow.

CONCLUSIONS

The results of this preclinical study showed that the 0.125-0.25-mm DBBM particles in a powder or paste formulation resulted in periodontal regeneration comparable to the commercially available DBBM. Osteoconductivity, in particular, was not affected by DBBM size or paste formulation.

CLINICAL RELEVANCE

The improved handling properties of the paste-like bone substitute consisting of small DBBM particles embedded in a collagen-based carrier hold promise for clinical applications.

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.

Mixed nano/micro-sized calcium phosphate composite and EDTA root surface etching improve availability of graft material in intrabony defects: an in vivo scanning electron microscopy evaluation

BACKGROUND

The use of nanoparticles of graft materials may lead to breakthrough applications for periodontal regeneration. However, due to their small particle size, nanoparticles may be eliminated from periodontal defects by phagocytosis. In an attempt to improve nanoparticle retention in periodontal defects, the present in vivo study uses scanning electron microscopy (SEM) to evaluate the potential of micrograft particles of β-tricalcium phosphate (β-TCP) to enhance the binding and retention of nanoparticles of hydroxyapatite (nHA) on EDTA-treated and non-treated root surfaces in periodontal defects after 14 days of healing.

METHODS

Sixty patients having at least two hopeless periodontally affected teeth designated for extraction were randomly divided into four treatment groups (15 patients per group). Patients in group 1 had selected periodontal intrabony defects grafted with nHA of particle size 10 to 100 nm. Patients in group 2 were treated in a similar manner but had the affected roots etched for 2 minutes with a neutral 24% EDTA gel before grafting of the associated vertical defects with nHA. Patients in group 3 had the selected intrabony defects grafted with a composite graft consisting of equal volumes of nHA and β-TCP (particle size 63 to 150 nm). Patients in group 4 were treated as in group 3 but the affected roots were etched with neutral 24% EDTA as in group 2. For each of the four groups, one tooth was extracted immediately, and the second tooth was extracted after 14 days of healing for SEM evaluation.

RESULTS

Fourteen days after surgery, all group 1 samples were devoid of any nanoparticles adherent to the root surfaces. Group 2 showed root surface areas 44.7% covered by a single layer of clot-blended grafted particles 14 days following graft application. After 14 days, group 3 samples appeared to retain fibrin strands devoid of grafted particles. Immediately extracted root samples of group 4 had adherent graft particles that covered a considerable area of the root surfaces (88.6%). Grafted particles appeared to cover all samples in a multilayered pattern. After 14 days, the group 4 extracted samples showed multilayered fibrin-covered nano/micro-sized graft particles adherent to the root surfaces (78.5%).

CONCLUSION

The use of a composite graft consisting of nHA and microsized β-TCP after root surface treatment with 24% EDTA may be a suitable method to improve nHA retention in periodontal defects with subsequent graft bioreactivity.