The effect of hyaluronan on bone and soft tissue and immune response in wound healing

Hyaluronic acid in Dentoalveolar regeneration: Biological rationale and clinical applications

Background

Hyaluronic acid (HA) is found in different locations in the periodontium, including mineralized tissues (i.e., cementum and alveolar bone) and non-mineralized tissues (i.e., gingiva and periodontal ligament). In addition, it seems to play an essential part in regulating the underlying mechanisms involved in tissue inflammatory reactions and wound healing. HA has the potential to regulate periodontal tissue regeneration and treat periodontal disease.

Aim

The current review of the literature was conducted to assess how HA plays its part in periodontal therapy and examine the contemporary literature's viewpoint on its use in periodontal regeneration.

Conclusion

HA has a multifunctional character in periodontal regeneration, and healing and appears to provide promising outcomes in different periodontal regenerative applications.

The Effect of Adjunctive Use of Hyaluronic Acid on Prevalence of Porphyromonas gingivalis in Subgingival Biofilm in Patients with Chronic Periodontitis: A Systematic Review

Porphyromonas gingivalis (P. gingivalis) is a Gram-negative anaerobic bacterium that plays an important role in the development and progression of periodontitis. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan that has previously demonstrated antibacterial potential in vitro against multiple bacterial species, including P. gingivalis. The purpose of this systematic review is to evaluate the effectiveness of HA as an adjunctive topical antibacterial agent to non-surgical mechanical therapy of periodontitis in reducing the prevalence of P. gingivalis in subgingival biofilms. Five clinical studies were identified that satisfied the eligibility criteria. Only three trials were suitable for the meta-analysis as they provided data at three and six months. Data on the prevalence of P. gingivalis in each study were collected. The odds ratio (OR) for measuring the effect size with a 95% confidence interval (CI) was applied to the available data. The results did not favor the use of HA during non-surgical mechanical therapy to reduce the prevalence of P. gingivalis in subgingival biofilm (odd ratio = 0.95 and 1.11 at three and six months, consecutively). Within their limitations, the current data do not indicate an advantage for using HA during mechanical periodontal therapy to reduce the prevalence of P. gingivalis.

Drug Release and Cytotoxicity of Hyaluronic Acid and Zinc Oxide Gels, An In-Vitro Study

Hyaluronic acid (HA) is a naturally occurring biopolymer, with a remarkable wound healing property. Zinc-oxide non-eugenol is a material widely used for periodontal dressing in dentistry. However, it has been reported that zinc oxide non-eugenol is toxic to osteoblasts and fibroblasts. Hence, the present study aimed to evaluate the drug release and cytotoxicity of HA and zinc-oxide gels. Hydrogels of HA and zinc oxide were formulated with carbopol as a carrier. In vitro drug release was performed by UV spectrophotometry, dialysis, and vial bag methods. Cytotoxicity assessment of HA and zinc-oxide gels was performed in human periodontal ligament fibroblasts (HPdLF) and human gingival fibroblasts (hGFs). An inverted phase-contrast microscope was used to assess the morphological changes. At 24 and 48 hr, HPdLF cells showed the highest viability in 0.1% low molecular weight-HA (LMW-HA) with a median value of 131.9, and hGFs showed the highest viability in 5% LMW-HA with a median of 129.56. The highest viability of HPdLF cells was observed in 5% high molecular weight-HA (HMW-HA), with a median value of 127.11. hGFs showed the highest viability in 1% HMW-HA with a median value of 97.99. Within the limitations of the present study, we concluded that LMW-HA is more efficient than HMW-HA. Both HPdLF and hGF cells showed complete cell morbidity with zinc-oxide hydrogels. Therefore, zinc oxide-based gels in concentrations as low as 9% could be toxic intraorally to soft tissues that harbor gingival and periodontal ligament fibroblasts.

Efficiency of Hyaluronic Acid in Infrabony Defects: A Systematic Review of Human Clinical Trials

Background and objectives: The aim of this systematic review was to assess the electronic literature about the benefits of using hyaluronic acid (HA) in the surgical periodontal treatment of infrabony defects. Materials and methods: This review was conducted under the PRISMA guidelines. The electronic search was conducted on PubMed, Scopus, Web of Science, and Cochrane databases until February 2022. The inclusion criteria consisted of human clinical trials that reported the use of HA in open-flap debridement (OFD) for infrabony defects. The assessment of risk of bias was performed using the Cochrane risk of bias tool. Statistical analysis was performed using Review Manager. Results: Overall, three RCTs were found eligible for the statistical analysis. Probing depth (PD) reduction and clinical attachment level (CAL) gain in the HA test group presented WMs of −1.11 mm (95% CI −2.38 to 0.16 mm; p = 0.09) and −1.38 mm (95% CI −2.26 to −0.49 mm; p = 0.002), respectively. However, the heterogeneity of the RCTs was high, and the risk of bias, in general, was low. Conclusions: The use of hyaluronic acid seems to have beneficial effects in periodontal surgery using OFD, in terms of PD and CAL. To draw a clear conclusion, more adapted and well-designed clinical trials are needed to assess the advantage of this product in comparison with other products.

A thermosensitive gel with an active hyaluronic acid ingredient that contains an octenidine preservation system as an adjunct to scaling and root planning: a randomized prospective clinical study

OBJECTIVES

To evaluate the adjunctive effect of a thermosensitive gel formulation that contains 0.8% oligo hyaluronic acid (HA) combined with a preservation system of octenidine HCl 0.625% and phenoxyethanol to scaling and root planing (SRP) as compared with SRP alone in the treatment of residual pockets of patients with stage 3 periodontitis.

MATERIALS AND METHODS

Thirty-four patients (21 males and 13 females) aged 29-78 years (51.3 ± 13.1) with stage 3 periodontitis were recruited to participate in the present split-mouth study. None of the patients has been previously treated for periodontitis. Plaque index (PI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were evaluated at baseline and at 3 and 6 months post treatment. Full-mouth SRP was performed in all residual pockets ≥ 5 mm. Treatment was performed by means of ultrasonic and hand instruments and lasted 45-60 min. The gel was applied subgingivally in the test sites immediately after SRP (baseline) and 1 month later. The paired t-test for two means was applied to test the statistical significance of the change from baseline within each arm and determine the difference between groups. The level of significance was set at 0.05 for all tests.

RESULTS

Mean PD reductions between baseline and 3 and 6 months were 1.98 mm and 2.79 mm for the test and 1.22 mm and 1.50 mm for the control group, respectively. Comparisons between the test and control groups revealed that SRP + gel yielded statistically significantly higher PD reductions compared to SRP alone (p < 0.0001). Compared to baseline, CAL and BOP values improved statistically significantly in both groups, although the test group presented statistically significantly higher CAL gains and BOP reductions than the control group (P < 0.0001).

CONCLUSION

In residual pockets of stage 3 periodontitis patients, the local application of a thermosensitive gel with an active HA ingredient and a preservation system of octenidine HCl 0.625% in conjunction with SRP may additionally improve the clinical outcomes obtained with SRP alone.

CLINICAL RELEVANCE

A novel HA and octenidine containing thermosensitive gel effectively improved the clinical parameters in stage 3 periodontitis patients over a 6-month period.

Combination of enamel matrix derivative and hyaluronic acid inhibits lipopolysaccharide-induced inflammatory response on human epithelial and bone cells

Objectives

The aim of this study was to evaluate the in vitro effect of enamel matrix derivative (EMD) and hyaluronic acid (HA) and their synergistic combination on lipopolysaccharides (LPS)-induced inflammation in human keratinocytes and osteoblasts.

Material and methods

Cells were challenged with LPS (1 μg/ml) and cultured in the following treatment groups with EMD (30 mg/ml) and HA (30 mg/ml): LPS, EMD, HA, EMD + HA, EMD + LPS, HA + LPS, and EMD + HA + LPS. Cell viability, inflammatory cytokine expression, and cell migration were determined using colorimetric assay, quantitative real-time polymerase chain reaction (qPCR), and scratch wound healing assay, respectively.

Results

Cell viability was decreased when exposed to LPS compared to the controls. Overall, LPS treatment expressed upregulation on inflammatory cytokine tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin 6 (IL-6). EMD and HA reduced up to 3.0-fold the cytokine expression caused by LPS (p < 0.05). EMD and HA statistically induced higher migration in osteoblasts and keratinocytes, respectively. Migration was impaired by LPS, whereas it significantly increased after addition of EMD and HA.

Conclusions

EMD and HA are advantageous biomaterials that individually generate strong directional migratory keratinocyte and osteoblast response. Their combination also enhances cell viability, and anti-inflammatory and migratory abilities to promote healing specially under LPS inflammatory stimulus. Future in vivo and animal research is necessary to further characterize the effect of EMD and HA on periodontal regeneration.

Clinical relevance

The use of EMD in conjunction with HA resulted in a reduction of inflammation and improvement of tissue healing at wound sites. Both biomaterials combined may potentially improve the effectiveness of bone regeneration in periodontal bone defects, pointing to the potential clinical relevance of both materials in regenerative periodontal surgery.

Clinical and radiographic evaluation of 0.8% hyaluronic acid as an adjunct to open flap debridement in the treatment of periodontal intrabony defects: randomized controlled clinical trial

OBJECTIVES

Present study aimed to evaluate and compare the clinical and radiographic efficacy of 0.8% hyaluronic acid (HA) gel as an adjunct to open flap debridement (OFD) versus open flap debridement (OFD) alone in the treatment of periodontal intrabony defects.

MATERIALS AND METHODS

This randomized, controlled, split-mouth, clinical trial included 20 chronic periodontitis (stage II or III (grades A to B)) patients, having at least two contralateral intrabony defects. Forty bilateral intrabony defects (20 in each group) were randomly divided into test (0.8% HA gel + OFD) and control (OFD + placebo) groups. Clinical parameters evaluated at baseline, 6-months, and 12-months were plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and gingival recession (GR). Using cone beam computed tomography (CBCT), radiographic parameters were evaluated at baseline and 12 months. This included bone defect fill (DF), alveolar crest changes (ACC), and defect resolution (DR). CAL served as the primary outcome variable.

RESULTS

After 12 months, the test group showed significantly greater CAL gain (5.1 ± 1.2 versus 4.05 ± 1.19 mm) and bone defect fill (DF) (5.67 ± 2.01 versus 4.49 ± 1.78 mm) compared to the control group. Mean PD reduction in the test group (5.3 ± 1.2 versus 4.35 ± 0.81 mm) was statistically significant compared to the control group at 12-month period. The control group showed statistically significant increase in GR (1.2 ± 0.76 versus 0.7 ± 0.73 mm) compared to the test group after 12 months.

CONCLUSION

Application of hyaluronic acid gel in conjunction with open flap debridement resulted in enhanced clinical and radiographic outcomes compared to open flap debridement alone.

CLINICAL RELEVANCE

Adjunctive application of HA gel in open flap debridement may improve clinical and radiographic outcomes.

CLINICAL TRIAL REGISTERED NUMBER

CTRI/2018/03/012334.

Healing of buccal gingival recessions following treatment with coronally advanced flap alone or combined with a cross-linked hyaluronic acid gel. An experimental study in dogs

Aim

To clinically and histologically evaluate in dogs the healing of gingival recessions treated with coronally advanced flap (CAF) with or without cross‐linked hyaluronic acid (HA).

Materials and methods

Gingival recession defects were surgically created on the vestibular side of both maxillary canines in 8 dogs. After 8 weeks of plaque accumulation, the 16 chronic defects were randomly treated with either CAF alone or CAF and HA‐gel (CAF/HA). Clinical and histological outcomes were evaluated at 10 weeks post‐surgically.

Results

Compared to baseline, the clinical measurements at 10 weeks revealed a statistically significant decrease in gingival recession for both CAF (p < 0.01) and CAF/HA (p < 0.001) groups. Statistically significant differences were found in clinical attachment level (p < 0.05) and width of gingival recession (p < 0.01) favouring the CAF/HA group. Bone formation was statistically significantly greater in the CAF/HA group than in the CAF group (1.84 ± 1.16 mm vs., 0.72 ± 0.62 mm, respectively, p < 0.05). Formation of cementum and connective tissue attachment were statistically significantly higher in the CAF/HA group compared with the CAF group (i.e. 4.31 ± 1.78 mm versus 2.40 ± 1.35 mm and 1.69 ± 0.98 mm versus 0.74 ± 0.68 mm, respectively (p < 0.05)).

Conclusions

The present data have for the first time provided histologic evidence for periodontal regeneration of gingival recession defects following treatment with CAF and HA.

Clinical relevance

The use of HA in conjunction with CAF may represent a novel modality for treating gingival recession defects.

Evaluation of biochemical and clinical effects of hyaluronic acid on non-surgical periodontal treatment: a randomized controlled trial

BACKGROUND

Recent studies reported that hyaluronic acid (HA) has anti-inflammatory, anti-edematous, and anti-bacterial activities in dentistry, particularly in gingival disorders caused by subgingival plaque microorganisms.

AIMS

This study aimed to evaluate the early term effects of HA as an adjunct to scaling and root planing (SRP) on clinical parameters, periodontal inflamed surface area (PISA), and adenosine deaminase (ADA), catalase (CAT), and glutathione (GSH) levels in gingival crevicular fluid (GCF) in periodontitis.

METHODS

A total of 24 periodontitis patients per group were included in this randomized-controlled study. The study population was divided into four groups: in Group 1: SRP+ saline; in Group 2: SRP + HA gel; in Group 3: SRP+ HA mouth rinse; and in Group 4: SRP + HA mouth rinse + HA gingival gel were applied. At baseline and week 4, clinical parameters and PISA were calculated. Also, biochemicals' (ADA, CAT, and GSH) levels were determined by spectrophotometric analysis.

RESULTS

There was a statistically significant improvement in clinical parameters and PISA in all four groups in control sessions (p < 0.05). There was a significant decrease in ADA in GCF and significant increases in CAT and GSH levels after SRP (p < 0.05) in all four groups. The groups that were administered only gel (2nd and 4th) were different from other groups in terms of ADA, CAT, and GSH levels at 1st week (p < 0.05).

CONCLUSION

HA application as an adjunct to SRP did not affect the clinical results, although, in the control sessions following the application, the results were favorable for the biochemical data in gel-applied groups.

TRIAL REGISTRATION

ClinicalTrials.gov.tr (NCT03754010).

Tissue-specific Fixation Methods Are Required for Optimal In Situ Visualization of Hyaluronan in the Ovary, Kidney, and Liver

Hyaluronan (HA) is a ubiquitous component of the extracellular matrix. The spatial-temporal localization of HA can be visualized in situ using biotinylated HA binding proteins (HABPs). This assay is sensitive to fixation conditions, and there are currently no best practices for HA detection. Thus, the goal of this study was to optimize fixation conditions for visualizing HA in the ovary, kidney, and liver through analysis of six commonly used fixatives for HA detection: Bouin's Solution, Carnoy's Solution, Ethanol-Formalin-Glacial Acetic Acid (EFG), Histochoice, Modified Davidson's Solution, and 10% Neutral Buffered Formalin. Organs were harvested from CB6F1 mice and fixed with one of the identified fixatives. Fixed organs were sectioned, and the HABP assay was performed on sections in parallel. Hematoxylin and eosin staining was also performed to visualize tissue architecture. HABP signal localization and intensity varied between fixatives. EFG and Carnoy's Solution best preserved the HA signal intensity in the ovary and liver, showing HA localization in various sub-organ structures. In the kidney, only Modified Davidson's Solution was less than optimal. Our findings demonstrate that fixation can alter the ability to detect HA in tissue macro- and microstructures, as well as localization in a tissue-specific manner, in situ.

Commercial Local Pharmacotherapeutics and Adjunctive Agents for Nonsurgical Treatment of Periodontitis: A Contemporary Review of Clinical Efficacies and Challenges

Periodontal infections tend to be site-specific, mostly confined to the periodontal pocket. With the surge of antibiotic-resistant bacteria, the trend is shifting towards other therapeutic modalities, especially locally delivered approaches that include other pharmacotherapeutic drugs and medical devices. This narrative review aimed to provide insights into the clinical efficacy of local drug delivery and adjunctive agents used in nonsurgical management of periodontitis. Electronic (PubMed/MEDLINE, CENTRAL, and EMBASE) and bibliographic searches of past systematic reviews were carried out to identify previous publications on the topic. Only relevant literature and randomized controlled trials published in English were selected. In addition, a literature review was developed based on the selected articles. Experimental drugs or agents were excluded. This review highlights the clinically proven and commercially available therapeutic agents related to the management of periodontal disease with comparisons of their clinical efficacies and challenges. A vast array of commercial local pharmacotherapeutic agents had been clinically tested, but the methodologies and clinical results varied within and between each agent used, causing difficulty in drawing conclusions and providing support to the superiority of one agent over another. Considering the benefit-cost ratio with the modest clinical results, the long-term usefulness of these agents remains debatable.

Single application of 0.8% hyaluronic acid as a coadjuvant of nonsurgical treatment in nonsmoking patients with periodontitis: A split-mouth, randomized, controlled pilot clinical trial

Background:

Topical coadjuvants might be indicated to increase the results of nonsurgical periodontal treatment and overcome some of its limitations. The aim of this study was to evaluate the clinical benefits of a single topical application of 0.8% hyaluronic acid (HA) as a coadjuvant to scaling and root planing (SRP) in periodontal patients.

Materials and Methods:

Sixteen patients diagnosed with periodontitis were recruited to participate in this split-mouth randomized controlled trial. At baseline, oral hygiene instructions, prophylaxis, and SRP were performed in both sides; additionally, a subgingival application of HA at 0.8% was made in the test side. Several clinical parameters were assessed at baseline, 6, and 12 weeks later: full mouth plaque score, gingival score, bleeding on probing (BoP), probing depth (PD), and clinical attachment level (CAL).

Results:

At the end of 12 weeks, there was a overall improvement in all periodontal parameters in both sides (P < 0.05). Test sides showed less BoP when compared to the control sides (9.4 ± 4.0 vs. 14.9 ± 8.9, P < 0.05). Other periodontal parameters such as PD and CAL showed a slight improvement in comparison with the control sides, but the difference was not statistically significant (P > 0.05).

Conclusion:

Results from this study indicate that a single subgingival application of 0.8% HA seems to reduce gingival inflammation and improve clinical parameters, particularly BoP. Further studies are needed to evaluate the effect of repeated application of HA and long-term results.

Hyaluronic acid as adjunctive to non-surgical and surgical periodontal therapy: a systematic review and meta-analysis

OBJECTIVES

To evaluate the potential added benefit of the topical application of hyaluronic acid (HA) on the clinical outcomes following non-surgical or surgical periodontal therapy.

MATERIALS AND METHODS

A systematic search was performed in Medline, Embase, Cochrane, Web of Science, Scopus and Grey literature databases. The literature search was preformed according to PRISMA guidelines. The Cochrane risk of bias tool was used in order to assess the methodology of the included trials. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) between the treatment and controls were estimated using the random-effect model for amount of bleeding on probing (BOP), probing depth (PD) reduction and clinical attachment level (CAL) gain. In order to minimize the bias and to perform meta-analysis, only randomized clinical studies (RCTs) were selected.

RESULTS

Thirteen RCTs were included: 11 on non-surgical periodontal treatment and two on surgical periodontal treatment. Overall analysis of PD reduction, CAL gain and BOP reduction in non-surgical therapy with adjunctive HA presented WMD of - 0.36 mm (95% CI - 0.54 to - 0.19 mm; p < 0.0001), 0.73 mm (95% CI 0.28 to 1.17 mm; p < 0.0001) and - 15% (95% CI - 22 to - 8%; p < 0.001) respectively, favouring the application of HA. The overall analysis on PD and CAL gain in surgical therapy with adjunctive HA presented WMD of - 0.89 mm (95% CI - 1.42 to - 0.36 mm; p < 0.0001) for PD reduction and 0.85 mm (95% CI 0.08 to 1.62 mm; p < 0.0001) for CAL gain after 6-24 months favouring the treatment with HA. However, comparison presented considerable heterogeneity between the non-surgical studies and a high risk of bias in general.

CONCLUSIONS

Within their limits, the present data indicate that the topical application of HA may lead to additional clinical benefits when used as an adjunctive to non-surgical and surgical periodontal therapy. However, due to the high risk of bias and heterogeneity, there is a need for further well-designed RCTs to evaluate this material in various clinical scenarios.

CLINICAL RELEVANCE

The adjunctive use of HA may improve the clinical outcomes when used in conjunction with non-surgical and surgical periodontal therapy.

Generation of novel hyaluronic acid biomaterials for study of pain in third molar intervention: a review

Hyaluronic acid (HA) has long been studied in diverse applications. It is a naturally occurring linear polysaccharide in a family of unbranched glycosaminoglycans, which consists of repeating di-saccharide units of N-acetyl-D-glucosamine and D-glucuronic acid. It is almost ubiquitous in humans and other vertebrates, where it participates in many key processes, including cell signaling, tissue regeneration, wound healing, morphogenesis, matrix organization, and pathobiology. HA is biocompatible, biodegradable, muco-adhesive, hygroscopic, and viscoelastic. These unique physico-chemical properties have been exploited for several medicinal purposes, including recent uses in the adjuvant treatment for chronic inflammatory disease and to reduce pain and accelerate healing after third molar intervention. This review focuses on the post-operative effect of HA after third molar intervention along with its various physio-chemical, biochemical, and pharmaco-therapeutic uses.

Effect of hyaluronic acid on the osseointegration of dental implants

The mechanism of osseointegration is related to many factors, including the quality of the bone, the biocompatibility and surface characteristics of the implant material, the surgical technique, and functional loading. The purpose of this study was to investigate the effects of hyaluronic acid gel on the osseointegration of implants placed in defined areas of the mandible in rabbits. Hyaluronic acid is known to have an osteoinductive effect during regeneration of bony defects, and we thought that it might also have a favourable effect on osseointegration, a specialised mechanism to heal bone. Ten New Zealand rabbits aged 10 weeks and weighing 2.5-3.0kg were used, and sites for implants that were far enough from the apices of the teeth in the mandibular molar area were chosen. Two cavities were prepared in each rabbit, one (anterior) for the control implant, and one (posterior) for the implant with hyaluronic acid gel (Medical Instinct GmbH, Bovenden). New bone and the osteoid matrix content around the dental implants were evaluated histologically and histomorphometrically two months after the operation, and no significant difference was found between the two groups.

Hyaluronic acid: Perspectives in dentistry. A systematic review

To date, topical therapies guarantee a better delivery of high concentrations of pharmacologic agents to the soft periodontal tissue, gingiva, and periodontal ligament as well as to the hard tissue such as alveolar bone and cementum. Topical hyaluronic acid (HA) has recently been recognized as an adjuvant treatment for chronic inflammatory disease in addition to its use to improve healing after dental procedures. The aim of our work was to systematically review the published literature about potential effects of HA as an adjuvant treatment for chronic inflammatory disease, in addition to its use to improve healing after common dental procedures. Relevant published studies were found in PubMed, Google Scholar, and Ovid using a combined keyword search or medical subject headings. At the end of our study selection process, 25 relevant publications were included, three of them regarding gingivitis, 13 of them relating to chronic periodontitis, seven of them relating to dental surgery, including implant and sinus lift procedures, and the remaining three articles describing oral ulcers. Not only does topical administration of HA play a pivotal key role in the postoperative care of patients undergoing dental procedures, but positive results were also generally observed in all patients with chronic inflammatory gingival and periodontal disease and in patients with oral ulcers.

Evaluation of effectiveness of hyaluronic acid in combination with bioresorbable membrane (poly lactic acid-poly glycolic acid) for the treatment of infrabony defects in humans: A clinical and radiographic study

Background:

The combination of biomaterials, bone graft substitutes along with guided tissue regeneration (GTR) has been shown to be an effective modality of periodontal regenerative therapy for infrabony defects. Therefore, the present randomized controlled clinical study was undertaken to evaluate the effectiveness of hyaluronic acid (HA) in combination with bioresorbable membrane for the treatment of human infrabony defects.

Materials and Methods:

Twenty four infrabony defects in 20 systemically healthy patients were randomly assigned to test (HA in combination with bioresorbable membrane) and control (bioresorbable membrane alone) treatment groups. Probing pocket depth (PPD), relative attachment level, and relative gingival margin level were measured with a computerized Florida disc probe at baseline and at 6 months follow-up. Radiographic measurements were also evaluated at baseline and at 6 months of postsurgery.

Results:

At 6 months, the mean reduction in PPD in test group and control group was 4.52 mm and 2.97 mm, respectively. Significantly higher clinical attachment level with a gain of 2.20 mm was found in the test group as compared to control group. In addition, statistically significant greater reduction of radiographic defect depth was observed in the test group.

Conclusion:

Regenerative approach using hyaloss in combination with GTR for the treatment of human infrabony defects resulted in a significant added benefit in terms of CAL gains, PPD reductions and radiographic defect fill, as well as LBG, compared to the GTR alone.

To compare the effect of the local delivery of hyaluronan as an adjunct to scaling and root planing versus scaling and root planing alone in the treatment of chronic periodontitis

Background:

Hyaluronan is a critical component of the extracellular matrix and contributes significantly to tissue hydrodynamics and cell migration and proliferation. Studies have demonstrated its anti-inflammatory, antibacterial, and regenerative effects. The present study aimed to assess the clinical effects of the subgingival application of 0.8% hyaluronic acid gel as an adjunct to scaling and root planing (SRP) in the treatment of generalized chronic periodontitis.

Materials and Methods:

Patients with chronic periodontitis were recruited to participate in a study with a split-mouth design and provided informed consent. One hundred sites were included in the study and divided into fifty test sites and fifty control sites. These were assessed for plaque index (PI), gingival index (GI), pocket probing depths, and relative attachment level (RAL) at-pretreatment (baseline), 4, and 12 weeks posttreatment. The patients received full-mouth SRP. A 0.8% hyaluronan gel was administered subgingivally in the test sites at baseline and after 1 week. Significant differences between test and control were evaluated using the t-test, analysis of variance (test) followed by Bonferroni post hoc test.

Results:

A significant reduction in PI and GI was observed in both groups at 12 weeks (P < 0.05). Significant reduction in the pocket probing depths and gain RAL was observed in both the groups as compared to baseline (P < 0.05). The hyaluronan group compared to control at 12 weeks showed statistically significant reduction in the probing pocket depth and gain in RAL (P < 0.05).

Conclusion:

The subgingival application of 0.8% hyaluronan gel in conjunction with SRP may have a beneficial effect on periodontal health in patients with chronic periodontitis.

Hyaluronic Acid as an adjunct to scaling and root planing in chronic periodontitis. A randomized clinical trail

AIM

AIM of the present study was to evaluate the adjunctive effect of local application of hyaluronon gel following scaling and root planing (SRP) in chronic periodontitis patients.

MATERIALS AND METHODS

In this randomized split mouth study 33 subjects with chronic periodontitis were evaluated after full mouth SRP. In the test sites hyaluronon gel was applied immediately after SRP and one week post therapy, the control sites were treated with SRP alone. Bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded at baseline, 4 wk and 12 wk.

RESULTS

Significant reduction in BOP scores was observed in both the groups at 12weeks (p<0.001). The hyaluronon group showed a greater reduction in BOP (p<0.001). In the hyaluronon group the mean PPD at baseline was 6.33±0.09 which reduced to 2.49±0.51 at 12 weeks which was statistically significant (p<0.001). In the control group the mean PPD at baseline was 6.09±1.26 which reduced to 4.36±1.29 at 12 weeks which was statistically significant (p<0.001). The CAL measurements showed a significant difference between the groups (p<0.001) at 12 wk post therapy.

CONCLUSION

Hyaluronic Acid (HA) has a beneficial effect on periodontal health in patients with chronic Periodontitis. HA appears to be a suitable candidate as an adjunct to SRP in chronic periodontitis patients.

Hyaluronic Acid: a boon in periodontal therapy

Hyaluronic acid is a naturally occurring linear polysaccharide of the extracellular matrix of connective tissue, synovial fluid, and other tissues. Its use in the treatment of the inflammatory process is established in medical areas such as orthopedics, dermatology, and ophthalmology. The Pubmed/Medline database was searched for keywords “Hyaluronic acid and periodontal disease” and “Hyaluronic acid and gingivitis” which resulted in 89 and 22 articles respectively. Only highly relevant articles from electronic and manual search in English literature were selected for the present review article. In the field of dentistry, hyaluronic acid has shown anti-inflammatory and anti-bacterial effects in the treatment of periodontal diseases. Due to its tissue healing properties, it could be used as an adjunct to mechanical therapy in the treatment of periodontitis. Further studies are required to determine the clinical efficacy of hyaluronic acid in healing of periodontal lesion. The aim of the present review, article is to discuss the role of hyaluronic acid in periodontal therapy.

Effect of hyaluronan on periodontitis: A clinical and histological study

BACKGROUND

Conventional, non-surgical periodontal therapy consists of supra- and subgingival tooth debridement. However, it is a technically demanding procedure and is not always efficient at eradicating all periodontal pathogens and in reducing inflammation. Therefore, local subgingival application of other chemotherapeutic agents may be used as an adjunct to non-surgical therapy. The aim of this study was to investigate the clinical and histological outcomes of local subgingival application of 0.2% hyaluronic acid gel (GENGIGEL®) as an adjunct to scaling and root planing (SRP) in chronic periodontitis patients.

MATERIALS AND METHODS

One hundred and twenty sites were chosen from 26 patients with chronic periodontitis (criteria being periodontal pockets ≥5mm). Experimental sites additionally received HA gel subgingivally at baseline, 1(st), 2(nd), and 3(rd) week. Clinical parameters were re-assessed at 4(th), 6(th), and 12(th) week. At 4(th) week recall, a gingival biopsy was obtained from test and control site for histologic examination.

RESULTS

Intra-group analysis of all the clinical parameters at all sites from baseline to 4(th), 6(th), and 12(th) week showed statistically significant changes. Experimental sites showed statistically significant improvement in Gingival index and Bleeding index at 6(th) and 12(th) week when compared with control sites. However, no statistically significant differences were observed in the PPD and RAL between control and experimental sites at 4(th), 6(th), and 12(th) week time interval. No statistically significant association was found between the histological grading of the sites that received HA treatment.

CONCLUSION

Subgingival placement of 0.2% HA gel along with SRP provided a significant improvement in gingival parameters. However, no additional benefit was found in periodontal parameters. Histologically, experimental sites showed reduced inflammatory infiltrate, but it was not statistically significant.

Esterified hyaluronic acid and autologous bone in the surgical correction of the infra-bone defects

We study the osteoinductive effect of the hyaluronic acid (HA) by using an esterified low-molecular HA preparation (EHA) as a coadjuvant in the grafting processes to produce bone-like tissue in the presence of employing autologous bone obtained from intra-oral sites, to treat infra-bone defects without covering membrane. We report on 9 patients with periodontal defects treated by EHA and autologous grafting (4 males and 5 females, all non smokers, with a mean age of 43.8 years for females, 40.0 years for males and 42 years for all the group, in good health) with a mean depth of 8.3 mm of the infra-bone defects, as revealed by intra-operative probes. Data were obtained at baseline before treatment and after 10 days, and subsequently at 6, 9, and 24 months after treatment. Clinical results showed a mean gain hi clinical attachment (gCAL) of 2.6mm of the treated sites, confirmed by radiographic evaluation. Such results suggest that autologous bone combined with EHA seems to have good capabilities in accelerating new bone formation in the infra-bone defects.

Inflammatory mediator release following bone grafting in humans: a pilot study

AIM

The aim of this pilot study was to track markers of periodontal inflammation and bone resorption associated with decalcified freeze-dried bone allografts.

MATERIAL AND METHODS

Eleven subjects completed standardized treatment of intrabony defects > or =3 mm with allografts. Gingival crevicular fluid was collected from the defect site and an adjacent interproximal site within the surgical field at baseline, 2, 4, and 8 weeks post-operatively, and analysed for biochemical markers of inflammation/bone resorption. Probing depth, recession, bleeding on probing, plaque, and 6-month radiographic bone height change were measured.

RESULTS

Both prostaglandin E(2) (p=0.007) and bone-specific type 1 collagen (p=0.01) increased in crevicular fluid after 2 weeks in the bone graft sites. Matrix metalloproteinase-9 levels remained constant over time. There were positive correlations between prostaglandin levels during the first 8 weeks and bone height change over 6 months.

CONCLUSIONS

Periodontal bone grafts stimulate an inflammatory response during the first 2 weeks post-operatively, and the potential negative effects of inhibiting prostaglandins post-operatively should be investigated further.

A bridging demineralized bone implant facilitates posterolateral lumbar fusion in New Zealand white rabbits

STUDY DESIGN

Randomized controlled animal study.

OBJECTIVE

Test the effectiveness of a single-strip demineralized bone matrix with hyaluronan and gelatin.

SUMMARY OF BACKGROUND DATA

Demineralized bone matrix is widely used to augment spinal fusion, however, the effect of changing the physical characteristic and carrier is not known.

METHODS

Demineralized bone matrix was extracted from the bones of New Zealand White rabbits, and combined with hyaluronan and gelatin to form solid strips. Forty-eight rabbits were randomized into a control and 2 experimental groups. In the control group, fusion was attempted with autograft bone. For group 2, demineralized bone matrix strips alone and for group 3, autograft and demineralized bone matrix strips were used. The fusion was assessed with manual manipulation and radiographs. The volume of the fusion mass was determined from computed tomographic images.

RESULTS

By the manual palpation test, the fusion rates were 37.5%, 93.8%, and 100%, for groups 1-3, respectively (P < 0.05). By radiography, the control group fusion rate was 68.7% compared with 100% for the experimental groups (P < 0.05). The mean bone volumes of the fusion mass were 2142.2 +/- 318.5, 3132.9 +/- 632.1, and 4181.6 +/- 609.5 mm3 for groups 1-3, respectively (P < 0.05).

CONCLUSIONS

The demineralized bone matrix-gel strip was able to function as both a bone-graft enhancer and a bone graft substitute in rabbit posterolateral spine fusion.

Augmentation of rabbit posterolateral spondylodesis using a novel demineralized bone matrix-hyaluronan putty

STUDY DESIGN

Posterolateral spinal fusion with allogeneic demineralized bone graft-hyaluronan putty in addition to autogenous iliac crest bone graft in a rabbit model.

OBJECTIVES

To determine the potential efficacy of demineralized bone graft-hyaluronan putty as a bone graft enhancer.

SUMMARY OF BACKGROUND DATA

Autograft bone is the material of choice for posterolateral lumbar intertransverse process fusion. Bone graft alternatives such as demineralized bone matrices that can be used as graft extenders, enhancers, or substitutes continue to be developed.

METHODS

One hundred New Zealand white rabbits underwent bilateral posterolateral spinal fusion with autogenous iliac crest bone graft or bone graft with allogeneic rabbit demineralized bone graft-hyaluronan putty. The rabbits were killed 9 weeks later, and the lumbar spines were removed. Manual manipulation and fine detail radiography were used to assess spinal fusion, and computed tomographic images were used to quantify the volume of the fusion mass.

RESULTS

In comparison with autograft bone alone, the fusion rates were greater when demineralized bone graft-hyaluronan putty was used as an adjunct to autogenous bone. Furthermore, the radiographic fusion rate was greater when demineralized bone graft-hyaluronan putty was used in a 2:1 ratio to autograft bone in comparison with a 1:1 ratio (P = 0.001). The addition of demineralized bone graft-hyaluronan putty to autograft bone was found to increase mineralized bone volume in a ratio-dependent manner (P < 0.05).

CONCLUSIONS

Allogeneic demineralized bone matrix-hyaluronan putty enhances rabbit posterolateral spine fusion when used as an adjunct to autogenous bone graft. This new formulation of demineralized bone matrix may facilitate greater bone formation and successful fusion.