Subgingival delivery of therapeutic agents in the treatment of periodontal diseases

In Vitro Release Dynamics of Atorvastatin-Loaded Alginate Particles for Enhanced Periodontal Treatment

Periodontitis is a chronic inflammatory condition of the periodontium, which often leads to tooth loss. Recently, statins have emerged as potent anti-inflammatory agents with pleiotropic effects that can potentially outperform conventional periodontal treatments. However, the clinical application of statins is limited by the lack of suitable drug carriers that fit the periodontal region and provide a controlled local drug release. In this study, we address the critical gap in localized periodontal drug delivery and introduce an ultrasound-assisted technique to encapsulate atorvastatin within alginate microparticles (10-400 µm in diameter)-a simple, scalable, and biocompatible solution. While ultrasound is widely used in polymer synthesis, its application in alginate polymerization remains underexplored. To mimic physiological conditions, particles were incubated in artificial saliva at 37 °C, with drug release being analyzed via high-performance liquid chromatography. A methylcellulose-based hydrogel served as a conventional reference product. Results revealed that alginate particles exhibited at least a 10-fold increase in mean dissolution time compared to the methylcellulose gel, indicating superior stability. Increasing atorvastatin concentration extended the time interval needed for 50% of the drug to be released (t50%) from 1 h to 11 h, maintaining the overall drug diffusion level for several days. Further analysis showed that covalent cross-linking of alginate with divinyl sulfone significantly delayed the initial drug release by 3 h (p < 0.05) due to the additional molecular stabilization. These findings underscore the utility of ultrasonic atomization for the processing of alginate-based formulations. Given the ease of production, biocompatibility, and small size, successfully fabricated alginate particles represent a promising carrier for delivery of statins or other related drugs in clinical dentistry.

Xanthan-based chlorhexidine gel effects in non-surgical periodontal therapy? A meta-analysis

OBJECTIVE

To carry out a systematic review and meta-analysis of randomized controlled clinical trials (RCTs) and controlled clinical trials (CCTs) comparing scaling and root planing (SRP) or placebo with subgingival application of xanthan-based CHX (chlorhexidine) gel as adjunct to SRP.

MATERIALS AND METHODS

The literature search was carried out in PubMed/MEDLINE, EMBASE, and SCOPUS; primary outcomes were probing pocket depth (PPD) reduction and gain in clinical attachment level (CAL).

RESULTS

Overall, 15 studies were included. Three studies were judged to be at moderate risk of bias while the remaining 12 were rated at high risk of bias. A significant improvement in PPD reduction (standardized mean difference, SMD, 0.87, 95% CI, 0.41-1.34) and CAL gain (SMD = 0.84, 95% CI, 0.36-1.33) emerged for the SRP + CXH gel compared to the SRP alone group, in the presence of significant high heterogeneity among the studies.

CONCLUSIONS

Our systematic review and meta-analysis showed that xanthan-based chlorhexidine gel as adjunct to non-surgical periodontal therapy gives benefit in terms of PPD reduction and CAL gain as compared to non-surgical periodontal therapy only. Since there was high heterogeneity among studies and the quality of the evidence is low, further studies characterized by a better methodology, adequate sample size and longer follow-up are warranted in the next future.

REGISTRATION

The protocol of this scoping review was registered in the International Prospective Register of Systematic Reviews (https://www.crd.york.ac.uk/PROSPERO) with ID: CRD42023391589.

Evaluation of Clinical Efficacy of Biodegradable Chip Containing Salvadora persica (miswak) Extract in Chitosan Base as an Adjunct to Scaling and Root Planing in the Management of Periodontitis

Objectives

This study attempted to develop 2 biodegradable periodontal chips containing Salvadora persica (miswak) or benzyl isothiocyanate (BITC) extracts and evaluate their clinical effectiveness in managing periodontitis.

Methods

This clinical trial was conducted at the Faculty of Dentistry, Universiti Teknologi MARA Shah Alam, Selangor, Malaysia, from September 2010 to April 2012. Periodontal chips were formulated using S. persica, benzyl isothiocyanate (BITC) and chitosan extracts. All patients were treated with full mouth scaling and root planing at baseline. Thereafter, the periodontal pockets (≥5 mm in length) were divided into 4 groups: the control group; group 2 (plain chitosan chip); group 3 (S. persica extract); and group 4 (BITC extract). Plaque index (PI), bleeding on probing (BOP), periodontal probing pocket depth and clinical attachment levels were recorded at days 0 and 60 only.

Results

A total of 12 patients participated in this study. Overall, 240 periodontal pockets were evaluated. The study revealed significant improvements in PI, BOP and reduction in periodontal pocket depth in all 4 groups (P <0.05). The improvement in clinical attachment level was significantly higher (P <0.001) among the group that received S. persica chips compared to the control and other chip-treated groups.

Conclusion

Periodontal chips containing S. persica can be used as adjuncts to treat patients with periodontitis.

Insights into Intra Periodontal Pocket Pathogenesis, Treatment, In Vitro-In Vivo Models, Products and Patents, Challenges and Opportunity

Periodontal disease is a multifactorial pathogenic condition involving microbial infection, inflammation, and various systemic complications. Here, a systematic and comprehensive review discussing key-points such as the pros and cons of conventional methods, new advancements, challenges, patents and products, and future prospects is presented. A systematic review process was adopted here by using the following keywords: periodontal diseases, pathogenesis, models, patents, challenges, recent developments, and 3-D printing scaffolds. Search engines used were "google scholar", "web of science", "scopus", and "pubmed", along with textbooks published over the last few decades. A thorough study of the published data rendered an accurate and deep understanding of periodontal diseases, the gap of research so far, and future opportunities. Formulation scientists and doctors need to be interconnected for a better understanding of the disease to prescribe a quality product. Moreover, prime challenges (such as a lack of a vital testing model, scarcity of clinical and preclinical data, products allowing for high drug access to deeper tissue regions for prolonged residence, lack of an international monitoring body, lack of 4D or time controlled scaffolds, and lack of successful AI based tools) exist that must be addressed for designing new quality products. Generally, several products have been commercialized to treat periodontal diseases with certain limitations. Various strategic approaches have been attempted to target certain delivery regions, maximize residence time, improve efficacy, and reduce toxicity. Conclusively, the current review summarizes valuable information for researchers and healthcare professional to treat a wide range of periodontal diseases.

Chitosan nanoparticle applications in dentistry: a sustainable biopolymer

The epoch of Nano-biomaterials and their application in the field of medicine and dentistry has been long-lived. The application of nanotechnology is extensively used in diagnosis and treatment aspects of oral diseases. The nanomaterials and its structures are being widely involved in the production of medicines and drugs used for the treatment of oral diseases like periodontitis, oral carcinoma, etc. and helps in maintaining the longevity of oral health. Chitosan is a naturally occurring biopolymer derived from chitin which is seen commonly in arthropods. Chitosan nanoparticles are the latest in the trend of nanoparticles used in dentistry and are becoming the most wanted biopolymer for use toward therapeutic interventions. Literature search has also shown that chitosan nanoparticles have anti-tumor effects. This review highlights the various aspects of chitosan nanoparticles and their implications in dentistry.

Efficacy and Viability of Subgingival Application of Probiotics as an Adjunct to Scaling and Root Planing in Periodontitis

AIM

This study aimed to compare the efficacy of subgingivally applied probiotics as an adjunct to scaling and root planing (SRP) vs SRP alone in patients with periodontitis.

MATERIALS AND METHODS

Patients diagnosed with periodontitis, with probing pocket depth (PPD) of 5-7 mm on at least two teeth on contralateral sites, were selected for the study and randomly allocated to the test group (n = 31) who underwent SRP along with subgingival application of probiotic paste and the control group (n = 31) who underwent only SRP. Clinical parameters were evaluated in both groups at baseline and after 12 weeks. The viability of probiotic bacteria was evaluated in the test group at baseline, day 4 and day 8.

RESULTS

All clinical parameters showed a statistically significant difference between baseline and 12 weeks on intragroup and intergroup comparison, with a greater improvement in the test group. Microbiological evaluation showed that the mean colony-forming units (CFUs) in the test group were 38.39 ± 7.76, 7.25 ± 2.72 and 1.57 ± 1.29 at baseline, day 4 and day 8, respectively. The mean CFUs significantly reduced with an increase in time from baseline to 8-day time interval.

CONCLUSION

It was seen that the probiotic bacteria remained viable in the periodontal pocket for up to 8 days after placement, but stable improvements were seen in all clinical parameters even at 12 weeks, indicating its prolonged efficacy. Thus, commercially available probiotics can prove to be an inexpensive method to treat periodontitis when combined with SRP.

Supra and subgingival application of antiseptics or antibiotics during periodontal therapy

Periodontal diseases (gingivitis and periodontitis) are characterized by inflammatory processes which arise as a result of disruption of the balance in the oral ecosystem. According to the current S3 level clinical practice guidelines, therapy of patients with periodontitis involves a stepwise approach that includes the control of the patient's risk factors and the debridement of supra and subgingival biofilm. This debridement can be performed with or without the use of some adjuvant therapies, including physical or chemical agents, host modulating agents, subgingivally locally delivered antimicrobials, or systemic antimicrobials. Therefore, the main aim of this article is to review in a narrative manner the existing literature regarding the adjuvant application of local agents, either subgingivally delivered antibiotics and antiseptics or supragingivally applied rinses and dentifrices, during the different steps in periodontal therapy performed in Europe.

Antioxidant effect of spirulina in chronic periodontitis

BACKGROUND

Production of reactive oxygen species (ROS) by polymorpho nuclear neutrophils occurs in chronic periodontitis. These ROS are mainly involved in bacterial destruction. However, extracellular release of same results in destruction of surrounding tissue. Spirulina, a potent antioxidant when administered sub gingivally in pockets can offer improved results in chronic periodontitis patients. This study was conducted to evaluate the effect of Spirulina when delivered sub gingivally in patients with chronic periodontitis.

METHODS

Sixty chronic periodontitis patients were divided into 2 groups. Group I (n = 30) were treated with Scaling and Root planning (SRP) followed by placement of placebo (SRP-P) and in Group II (n = 30) Spirulina microspheres were placed sub gingivally (SRP-S) following SRP. Clinical parameters like bleeding on probing (BOP), clinical attachment level (CAL), gingival index (GI) and probing pocket depth (PPD) were evaluated. Levels of salivary and serum Malondialdehyde (MDA) were estimated using ultra violet spectrophotometer.

RESULTS

At baseline, in both groups there was no statistically significant difference in clinical and biochemical parameters. Intra group comparisons of parameters from baseline to 90 days were statistically significant in both groups. After 90 days difference in clinical parameters and salivary MDA levels were statistically significant in SRP-S compared to SRP-P group. Though serum MDA levels were reduced in both groups, they were not significant statistically.

CONCLUSIONS

Our study concluded that, local drug delivery of Spirulina adjunctive to SRP has potent antioxidant effect in treatment of chronic periodontitis.

Polymeric Nanotechnologies for the Treatment of Periodontitis: A Chronological Review

Periodontitis is a chronic infectious and inflammatory disease of periodontal tissues estimated to affect 70 - 80 % of all adults. At the same time, periodontium, the site of periodontal pathologies, is an extraordinarily complex plexus of soft and hard tissues, the regeneration of which using even the most advanced forms of tissue engineering continues to be a challenge. Nanotechnologies, meanwhile, have provided exquisite tools for producing biomaterials and pharmaceutical formulations capable of elevating the efficacies of standard pharmacotherapies and surgical approaches to whole new levels. A bibliographic analysis provided here demonstrates a continuously increasing research output of studies on the use of nanotechnologies in the management of periodontal disease, even when they are normalized to the total output of studies on periodontitis. The great majority of biomaterials used to tackle periodontitis, including those that pioneered this interesting field, have been polymeric. In this article, a chronological review of polymeric nanotechnologies for the treatment of periodontitis is provided, focusing on the major conceptual innovations since the late 1990s, when the first nanostructures for the treatment of periodontal diseases were fabricated. In the opening sections, the etiology and pathogenesis of periodontitis and the anatomical and histological characteristics of the periodontium are being described, along with the general clinical manifestations of the disease and the standard means of its therapy. The most prospective chemistries in the design of polymers for these applications are also elaborated. It is concluded that the amount of innovation in this field is on the rise, despite the fact that most studies are focused on the refinement of already established paradigms in tissue engineering rather than on the development of revolutionary new concepts.

Comparative Evaluation of Locally Administered 2% Gel Fabricated from Lemongrass Polymer and 10% Doxycycline Hyclate Gel as an Adjunct to Scaling and Root Planing in the Treatment of Chronic Periodontitis-A Randomized Controlled Trial

Background: Extracts of medicinal plant like lemongrass offer a new choice for optional antimicrobial therapy against various oral microorganisms. The objective of this study was to assess, verify, and compare the antimicrobial effectiveness of locally administered 2% lemongrass gel and 10% doxycycline hyclate gel as an adjunct to scaling and root planing (SRP) in treating chronic periodontitis. Method: This is a double-blind parallel arm randomized controlled study. Forty subjects were randomly divided into Group A and B for 2% lemongrass gel and 10% doxycycline hyclate gel, respectively. The clinical assessments of Gingival Index (GI), Plaque Index (PI), Probing Pocket Depth (PPD), and Clinical Attachment Level (CAL) together with microbial colony counts for Porphyromonas gingivalis, Actinomyces naeslundii, and Prevotella intermedia were done at baseline, 1st month, and 3rd month follow-ups. Results: The results showed there was a significant reduction in the mean scores of GI, PPD, and CAL clinical indices from baseline to the 1st and 3rd month follow-ups in both the 2% lemongrass gel and 10% doxycycline gel groups (p < 0.05). Similarly, there was significant reduction in mean CFU scores for all periodontal pathogens from baseline to 1st and 3rd month follow-ups in both the 2% lemongrass gel and 10% doxycycline gel groups (p < 0.05). Conclusions: It could be concluded that the local delivery of 2% lemongrass gel as an adjunct to scaling and root planing is effective and comparable to 10% doxycycline gel in the treatment of chronic periodontitis.

Meeting the challenges and clinical requirements for dental regeneration; the New Zealand experience

Disease and trauma leading to tooth loss and destruction of supporting bone is a significant oral handicap, which may be addressed through surgical therapies that aim to regenerate the lost tissue. Whilst complete regeneration of teeth is still aspirational, regeneration of supporting structures (dental pulp, cementum, periodontal ligament, bone) is becoming commonplace, both for teeth and for titanium dental implants that are used to replace teeth. Most grafting materials are essentially passive, however the next generation of oral regenerative devices will combine non-antibiotic antimicrobials and/or osteogenic or inductive factors and/or appropriate multipotential stem cells. The review gives an overview of the approaches taken, including fabrication of novel scaffolds, incorporation of growth factors and cell-based therapies, and discusses the preclinical animal models we employ in the development pathway.

Antimicrobial Activity of Roselle-capped​ Silver​ Nanochip on Aggregatibacter actinomycetemcomitans

OBJECTIVES

 This article aimed to study the effects of the​ roselle-capped​ silver​ nanochip​ ​(SNP-Ro​ chip)​ against Aggregatibacter actinomycetemcomitans, and the toxicity of this film on fibroblast cells to develop this SNP-Ro chip into a local chemical for the treatment of periodontitis in the future.

MATERIALS AND METHODS

 Using a microwave-assisted synthesis method, silver​ nanoparticles (SNPs) were prepared from a silver nitrate solution and roselle extract as a reducing and capping agent. Then, SNP-Ro chips were fabricated by mixing a solution of SNP-Ro with alginate gel. The antimicrobial effect of the synthesized SNP-Ro chips was performed by the disc diffusion technique and time kill assay. The cytotoxic effect was also determined by the MTS assay.

STATISTICAL ANALYSIS

 One-way analysis of variance (ANOVA) and Scheffe's method were used to analyze the data for this experiment.

RESULTS

 All three ratios of the SNP-Ro chip produced inhibition zones ranging between 18.75 ± 2.08 and 19.03 ± 2.25 mm. In studying the killing time, the three groups of the SNP-Ro chips completely eradicated A. actinomycetemcomitans within 180 minutes. The percentage of the viable SNP-Ro chip-treated human gingival fibroblasts (HGFs) were significantly increased when compared with the alginate chip-treated cells (p < 0.05).

CONCLUSION

 This study developed a new method for the deposition of SNPs in alginate gel to make a thin small chip for the sustained release of the SNPs in a periodontal lesion. Therefore, the SNP-Ro chip has the potential to be developed as an adjunctive locally delivered antimicrobial agent in periodontal therapy.

Treatment challenges and delivery systems in immunomodulation and probiotic therapies for periodontitis

Introduction: Periodontitis is a widespread illness that arises due to disrupted interplay between the oral microbiota and the host immune response. In some cases, conventional therapies can provide temporary remission, although this is often followed by disease relapse. Recent studies of periodontitis pathology have promoted the development of new therapeutics to improve treatment options, together with local application using advanced drug delivery systems.Areas covered: This paper provides a critical review of the status of current treatment approaches to periodontitis, with a focus on promising immunomodulation and probiotic therapies. These are based on delivery of small molecules, peptides, proteins, DNA or RNA, and probiotics. The key findings on novel treatment strategies and formulation of advanced delivery systems, such as nanoparticles and nanofibers, are highlighted.Expert opinion: Multitarget therapy based on antimicrobial, immunomodulatory, and probiotic active ingredients incorporated into advanced delivery systems for application to the periodontal pocket can improve periodontitis treatment outcomes. Translation of such adjuvant therapy from laboratory to patient is expected in the future.

Professionally Delivered Local Antimicrobials in the Treatment of Patients with Periodontitis-A Narrative Review

This review sheds light on the recent published scientific evidence relating to the use of professionally delivered local antimicrobial agents (LA’s). The review also analyses drug delivery systems available to date and provides an update on the latest scientific evidence about the benefits, limitations, and clinical results obtained by use of local drugs in the treatment of periodontal disease. The search strategy revealed randomized controlled trials (RCTs) that compared the efficacy of adjunctive LA’s to mechanical therapy alone. Based on the available evidence gathered from this review, we can infer that the use of local antimicrobial agents in conjunction to scaling and root debridement (SRD) delivers significant benefits in periodontal therapy and it is a useful aid, avoiding many of the side effects that systemic antibiotic therapy may involve. Local drug delivery (LDD) is an efficient and effective means of delivering drugs based on the evidence presented in the review. The authors of this review would suggest the use of local antimicrobials in cases of localized periodontitis or individual areas that do not respond to the usual mechanical therapy alone. This review summarizes the current use of local drug delivery in periodontal management ensuring that the general practitioners are able to choose an appropriate local antimicrobial.

Development of an antibacterial and anti-metalloproteinase dental adhesive for long-lasting resin composite restorations

Despite all the advances in adhesive dentistry, dental bonds are still fragile due to degradation events that start during application of adhesive agents and the inherent hydrolysis of resin-dentin bonds. Here, we combined two outstanding processing methods (electrospinning and cryomilling) to obtain bioactive (antimicrobial and anti-metalloproteinase) fiber-based fillers containing a potent matrix metalloproteinase (MMP) inhibitor (doxycycline, DOX). Poly(ε)caprolactone solutions containing different DOX amounts (0, 5, 25, and 50 wt%) were processed via electrospinning, resulting in non-toxic submicron fibers with antimicrobial activity against Streptococcus mutans and Lactobacillus. The fibers were embedded in a resin blend, light-cured, and cryomilled for the preparation of fiber-containing fillers, which were investigated with antibacterial and in situ gelatin zymography analyzes. The fillers containing 0, 25, and 50 wt% DOX-releasing fibers were added to aliquots of a two-step, etch-and-rinse dental adhesive system. Mechanical strength, hardness, degree of conversion (DC), water sorption and solubility, bond strength to dentin, and nanoleakage analyses were performed to characterize the physico-mechanical, biological, and bonding properties of the modified adhesives. Statistical analyses (ANOVA; Kruskal-Wallis) were used when appropriate to analyze the data (α = 0.05). DOX-releasing fibers were successfully obtained, showing proper morphological architecture, cytocompatibility, drug release ability, slow degradation profile, and antibacterial activity. Reduced metalloproteinases (MMP-2 and MMP-9) activity was observed only for the DOX-containing fillers, which have also demonstrated antibacterial properties against tested bacteria. Adhesive resins modified with DOX-containing fillers demonstrated greater DC and similar mechanical properties as compared to the fiber-free adhesive (unfilled control). Concerning bonding performance to dentin, the experimental adhesives showed similar immediate bond strengths to the control. After 12 months of water storage, the fiber-modified adhesives (except the group consisting of 50 wt% DOX-loaded fillers) demonstrated stable bonds to dentin. Nanoleakage was similar among all groups investigated. DOX-releasing fibers showed promising application in developing novel dentin adhesives with potential therapeutic properties and MMP inhibition ability; antibacterial activity against relevant oral pathogens, without jeopardizing the physico-mechanical characteristics; and bonding performance of the adhesive.

Multifunctional periodontal membrane for treatment and regeneration purposes

Periodontitis is a chronic inflammatory disease that causes gum tissue degeneration and alveolar bone and tooth loss. The aim of this study is to develop a multifunctional matrix for the treatment of periodontitis and enhancement of regeneration of the periodontal tissue. The matrix was prepared from vitamin E containing hydrogel made of alginate and gelatin, and doxycycline HCl containing methoxy poly(ethylene glycol)-block-polycaprolactone micelles. Methoxy poly(ethylene glycol)-block-polycaprolactone was synthesized with ring-opening polymerization technique and characterized by proton nuclear magnetic resonance (1H NMR), Fourier-transform infrared spectroscopy, differential scanning calorimetry, and gel permeation chromatography. Micelles were characterized by measuring zeta potential, hydrodynamic diameter, drug encapsulation efficiency, drug loading capacity, and in vitro drug-release kinetics. Micelles were obtained with an average size of 164 nm and drug loading amount of 5.8%. The activity of doxycycline HCl–loaded micelles and vitamin E containing hydrogels was determined against Escherichia coli ( E. coli) and Staphylococcus aureus ( S. aureus) with disk diffusion method. Bio-efficacy of micelle-loaded alginate–gelatin hydrogels were tested in vitro using L929 fibroblasts and dental pulp stem cells. Doxycycline HCl–loaded micelles and vitamin E containing hydrogels showed a sustained release and exhibited inhibition zone against E. coli and S. aureus. Hydrogels with vitamin E and doxycycline HCl–loaded micelles promoted osteogenic differentiation of dental pulp stem cells. Results suggest that alginate–gelatin hydrogels containing doxycycline HCl–loaded micelles and vitamin E can be good candidates for the treatment of periodontitis and tissue regeneration.

Doxycycline encapsulated in β-cyclodextrin for periodontitis: a clinical trial

This clinical trial compared the efficacy of doxycycline (DOX) in β-cyclodextrin (DOX)/βCD) with DOX- alone in gel on thirty-three subjects with periodontitis. Patients were randomized to group 1 GI; 10% DOX + scaling and root planning (SRP); group 2 (GII (10% DOX /β-CD + SRP), and group 3 (GIII; SRP). Gels were applied in GI and GII at baseline (T0) and 30 days later (T1). Periodontal Probing Depth (PPD), Clinical Attachment Level (CAL), Bleeding on Probing (BOP) and Visible Plaque Index (VPI) were evaluated at (T0), 30 days (T1) and 60 days after T0 (T2). Bone density was analyzed after 18 months (T3). GII showed the most significant reduction of PPD (2.62 mm; p <0.003), and greatest gain in CAL (2.54 mm p <0.003) at T2. BOP and the VPI had a strong reduction in all groups at T2 (p <0.05), both decreased by ≥5 times and 2 times, respectively, in all groups at T1. Bone density increased in all groups in radiographs (T3). The use of DOX encapsulated in β-CD gel with SRP resulted in significant improvements in clinical periodontal parameters; such molecular inclusion of doxycycline into β-CD in gel for local application is relatively simple and useful in dentistry.

Potential of chitosan-based carrier for periodontal drug delivery

Periodontal diseases are chronic infectious diseases and are a major oral health burden. With the progress in the understanding of etiology, epidemiology and pathogenesis of periodontal diseases coupled with the understanding of the polymicrobial synergy in the dysbiotic oral microbial flora, several new therapeutic targets have been identified. The strategies to curb bacterial growth and production of factors that gradually destroy the tissue surrounding and supporting the teeth have been the cornerstone for inhibiting periodontitis. Systemic administration of antibiotics for the treatment of periodontitis have shown several drawbacks including: inadequate antibiotic concentration at the site of the periodontal pocket, a rapid decline of the plasma antibiotic concentration to sub-therapeutic levels, the development of microbial resistance due to sub-therapeutic drug levels and peak-plasma antibiotic concentrations which may be associated with various side effects. These obvious disadvantages have evoked an interest in the development of localized drug delivery systems that can provide an effective concentration of antibiotic at the periodontal site for the duration of the treatment with minimal side effects. A targeted sustained release device which could be inserted in the periodontal pocket and prolong the therapeutic levels at the site of action at a much lower dose is the need of the hour. Chitosan, a deacetylated derivative of chitin has attracted considerable attention owing to its special properties including antimicrobial efficacy, biodegradability, biocompatibility and non-toxicity. It also has the propensity to act as hydrating agent and display tissue healing and osteoinducting effect. The aim of this review is to shine a spotlight on the chitosan based devices developed for drug delivery application in the effective treatment of various periodontal disorders. The chitosan based carriers like fibers, films, sponge, microparticles, nanoparticles, gels that have been designed for sustained release of drug into the periodontal pocket are highlighted.

Antimicrobial activity of NO-releasing compounds against periodontal pathogens

This study describes the successful synthesis of nitric oxide (NO)-releasing compounds with biodegradable and injectable properties and demonstrates that the kinetics of NO release vary according to the type of NO donor. The antimicrobial activity of NO-releasing compounds against three common periodontal pathogens, i.e., Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Actinomyces israelii, was investigated using a susceptibility assay. Human gingival fibroblasts were treated with NO-releasing compounds at the minimum concentrations required for bacterial growth and cytotoxicity was evaluated using the MTT cell proliferation assay. Our results suggest that NO-releasing compounds can be used topically to treat both gram-negative and gram-positive periodontal pathogens. Comparison of the antimicrobial activity and cytotoxicity assay results between the NO-releasing compounds revealed that an NO donor comprising a macromolecule without surface charge, a lower instantaneous NO concentration, and an adequate supply of NO were associated with a strong bactericidal effect and low cytotoxicity. NO-releasing compounds with these properties may be suitable for treatment of periodontitis.

In vitro evaluation of electrospun PLGA/PLLA/PDLLA blend fibers loaded with naringin for guided bone regeneration

The present study was to evaluate fiber mesh loaded with naringin via electrospinning to guide bone regeneration in vitro. The naringin-loaded fiber mesh was prepared via elctrospinning of PLGA, PLLA, PDLLA blending solution with naringin. SEM showed that naringin decreased the fiber's diameter according to the concentration of naringin. After 20 days' degradation in PBS, the drug-loaded fiber meshes still kept their stability with about 10% decrease in tensile strength. In vitro release experiments showed a sustained and steady naringin releasing profile with little initial burst releasing. Compared to the mats without naringin, the fiber mats loaded with naringin showed the most pronounced enhancement of cell growth when MC3T3-E1 cells were cultured on the fiber mats. The blend fiber loaded with naringin has optimized physical properties and sustained release profile in vitro. The study presents a promising fibrous mesh material for guided bone regeneration therapy.

Effect of 1.2% of simvastatin gel as a local drug delivery system on Gingival Crevicular Fluid interleukin-6 & interleukin-8 levels in non surgical treatment of chronic periodontitis patients

AIM

The present study was carried out to evaluate the effect of 1.2% simvastatin gel as local drug delivery (LDD) system on Gingival Crevicular Fluid (GCF) Interleukin -6 (IL-6) and Interleukin-8 (IL-8) levels in chronic periodontitis patients, in addition to scaling and root planing (SRP).

METHODS

A total of 46 chronic periodontitis patients were equally divided into two groups. Group I patients were treated by SRP; Group II patients were treated by SRP followed by LDD of 1.2% simvastatin (SMV) gel. Plaque index (PI), Gingival index(GI), Sulcus Bleeding Index (SBI), Probing pocket depth (PPD) and Relative clinical attachment level (CAL) were recorded & GCF samples were collected at baseline (0day) and at 45th day from both the groups. The collected GCF samples were analysed for IL-6 and IL-8 levels with enzyme-linked immunosorbent assay (ELISA).

RESULTS

Both the groups showed significant reduction in all the clinical parameters scores and IL-6 and IL-8 levels after non-surgical periodontal therapy (SRP for group I/SRP+1.2% SMV gel for group II) in contrast to baseline values. However, a greater reduction was observed in group II. A non-significant positive correlation was observed between clinical parameters and IL-6 and IL-8 levels except at baseline, a significant correlation was observed between PPD &IL 6 levels in group II.

CONCLUSIONS

In adjunct to SRP, 1.2% Simvastatin gel acts as an effective local drug delivery agent for the management of chronic periodontitis.

Efficacy of curcumin as an adjunct to scaling and root planning in chronic periodontitis patients: A clinical and microbiological study

Background and Objectives:

Curcumin is a naturally occurring anti-inflammatory agent with various biologic and medicinal properties. Its therapeutic applications have been studied in a variety of conditions, but only few studies have evaluated the efficacy of curcumin as local drug delivery agent and in the treatment of periodontitis. The present study was to evaluate the efficacy of the adjunctive use of curcumin with scaling/root planing as compared with scaling/root planing alone in the treatment of the chronic periodontitis.

Materials and Methods:

Thirty patients with two sites in the contralateral quadrants having probing pocket depths (PPDs) of ≥5 mm were selected. Full mouth scaling and root planing (SRP) was performed followed by application of curcumin gel on a single side. Assessment of plaque index (PI), gingival index (GI), PPD, and clinical attachment levels (CALs) were done at baseline and at 4^th week. Microbiologic assessment with polymerase chain reaction was done for Porphyromonas gingivalis, Tanerella forsythia, and Treponema denticola by collection of plaque samples.

Results:

The results revealed that there was a reduction in PI, GI, probing depth, CAL, and microbiologic parameters in test sites following SRP and curcumin gel application, when compared with SRP alone in control group.

Conclusion:

The local application of curcumin in conjunction with scaling and root planing have showed improvement in periodontal parameters and has a beneficial effect in patients with chronic periodontitis.

Functionalised nanoscale coatings using layer-by-layer assembly for imparting antibacterial properties to polylactide-co-glycolide surfaces

In order to achieve high local biological activity and reduce the risk of side effects of antibiotics in the treatment of periodontal and bone infections, a localised and temporally controlled delivery system is desirable. The aim of this research was to develop a functionalised and resorbable surface to contact soft tissues to improve the antibacterial behaviour during the first week after its implantation in the treatment of periodontal and bone infections. Solvent-cast poly(d,l-lactide-co-glycolide acid) (PLGA) films were aminolysed and then modified by Layer-by-Layer technique to obtain a nano-layered coating using poly(sodium4-styrenesulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) as polyelectrolytes. The water-soluble antibiotic, metronidazole (MET), was incorporated from the ninth layer. Infrared spectroscopy showed that the PSS and PAH absorption bands increased with the layer number. The contact angle values had a regular alternate behaviour from the ninth layer. X-ray Photoelectron Spectroscopy evidenced two distinct peaks, N1s and S2p, indicating PAH and PSS had been introduced. Atomic Force Microscopy showed the presence of polyelectrolytes on the surface with a measured roughness about 10nm after 20 layers' deposition. The drug release was monitored by Ultraviolet-visible spectroscopy showing 80% loaded-drug delivery in 14 days. Finally, the biocompatibility was evaluated in vitro with L929 mouse fibroblasts and the antibacterial properties were demonstrated successfully against the keystone periodontal bacteria Porphyromonas gingivalis, which has an influence on implant failure, without compromising in vitro biocompatibility. In this study, PLGA was successfully modified to obtain a localised and temporally controlled drug delivery system, demonstrating the potential value of LbL as a coating technology for the manufacture of medical devices with advanced functional properties.

In-situ forming composite implants for periodontitis treatment: How the formulation determines system performance

Periodontitis is the primary cause of tooth loss in adults and a very wide-spread disease. Recently, composite implants, based on a drug release rate controlling polymer and an adhesive polymer, have been proposed for an efficient local drug treatment. However, the processes involved in implant formation and the control of drug release in these composite systems are complex and the relationships between the systems' composition and the implants' performance are yet unclear. In this study, advanced characterization techniques (e.g., electron paramagnetic resonance, EPR) were applied to better understand the in-situ forming implants based on: (i) different types of poly(lactic-co-glycolic acid) (PLGA) as drug release rate controlling polymers; (ii) hydroxypropyl methylcellulose (HPMC) as adhesive polymer; and (iii) doxycycline or metronidazole as drugs. Interestingly, HPMC addition to shorter chain PLGA slightly slows down drug release, whereas in the case of longer chain PLGA the release rate substantially increases. This opposite impact on drug release was rather surprising, since the only difference in the formulations was the polymer molecular weight of the PLGA. Based on the physico-chemical analyses, the underlying mechanisms could be explained as follows: since longer chain PLGA is more hydrophobic than shorter chain PLGA, the addition of HPMC leads to a much more pronounced facilitation of water penetration into the system (as evidenced by EPR). This and the higher polymer lipophilicity result in more rapid PLGA precipitation and a more porous inner implant structure. Consequently, drug release is accelerated. In contrast, water penetration into formulations based on shorter chain PLGA is rather similar in the presence and absence of HPMC and the resulting implants are much less porous than those based on longer chain PLGA.

Comparative evaluation of the efficacy of two controlled release devices: Chlorhexidine chips and indigenous curcumin based collagen as local drug delivery systems

Aim:

To comparatively evaluate the therapeutic efficacy of chlorhexidine (CHX) chips (Periocol-CG) and indigenous curcumin (CU) based collagen as adjuncts to scaling and root planning in the nonsurgical management of chronic periodontitis.

Materials and Methods:

A total of 120 sites from 60 patients presenting with chronic periodontitis (age group 25-55 years) of both sexes, with pocket depth of ≥5 mm with radiographic evidence of bilateral bone loss were earmarked for the study. A split mouth design was employed, and all the clinical parameters-plaque index, gingival index, probing pocket depth (PPD) and clinical attachment levels (CAL) were recorded at baseline, 1 month, 3 months, and 6 months. However, the microbiological parameters, i.e., N-benzoyl-DL-arginine-β-naphthylamide (BANA) test and microbial colony count were recorded at baseline, 3 months and 6 months postoperatively.

Results:

Significant reduction in plaque and gingival index scores were observed in both groups at the end of the study period, i.e., 6 months. The microbiological parameters (BANA test, microbial colony count), PPD and CAL levels also showed significant improvement in both groups. However, at the end of the study period CHX group showed greater improvement in all of these parameters compared to CU collagen group.

Conclusion:

Future directions of this study should include targeting the beneficial effects of these local drug delivery systems at varied concentrations so that they could be utilized to achieve the maximum beneficial therapeutic effects in the nonsurgical treatment of periodontal disease.

Prolonged delivery of ciprofloxacin and diclofenac sodium from a polymeric fibre device for the treatment of periodontal disease

In vitro analysis of drug release and antimicrobial activity of the coblended crosslinked polymeric fibre device (PFD) were investigated. The fibre loaded with ciprofloxacin and diclofenac sodium was comprised of alginate and glycerol crosslinked with barium cations. The pH dependent drug release was evident with ciprofloxacin and diclofenac sodium diffusing from the fibre at pH 4.0 compared to pH 6.8, where the fibre swelled and eroded resulting in zero-order drug release. Agar diffusion studies followed by minimum inhibitory assays were conducted to determine the antimicrobial activity of the device against Escherichia coli, Enterococcus faecalis, and Streptococcus mutans. The antimicrobial activity of the PFD was confirmed in both test assays against all test pathogens. The MIC ranges at pH 4.0 for E. coli, E. faecalis, and S. mutans were 0.5-0.8, 0.4-1.1, and 0.7-2.1 μg/mL, respectively. At pH 6.8, similar efficacies (0.3-0.5 μg/mL for E. coli and E. faecalis and 0.6-1.0 μg/mL for S. mutans) were observed. The effect of varying the plasticizer and crosslinking ion concentration on drug release profile of the fibers was further elucidated and conceptualized using molecular mechanics energy relationships (MMER) and by exploring the spatial disposition of geometrically minimized molecular conformations.

Green tea extract as a local drug therapy on periodontitis patients with diabetes mellitus: A randomized case-control study

Background:

The green tea extract is a naturally occurring product having beneficial effects that counteract with the pathobiological features of periodontitis and diabetes mellitus. Hence, the present study was aimed at incorporation of green tea extract into hydroxylpropyl methylcellulose and investigates its efficacy in chronic periodontitis patients associated with and without diabetes mellitus.

Materials and Methods:

For the in vitro study, formulation of green tea strips and placebo strips, and analysis of drug release pattern from the green tea strips at different time intervals were performed. For the in vivo study, 50 patients (20-65 years), including 25 systemically healthy patients with chronic periodontitis (group 1) and 25 diabetic patients with chronic periodontitis (group 2) were enrolled. In each patient, test and control sites were identified for the placement of green tea and placebo strips, respectively. Gingival Index (GI), Probing Pocket Depth (PPD), and Clinical Attachment Level (CAL) were examined at baseline, first, second, third, and fourth weeks. Microbiological analysis for Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans was performed at baseline and fourth week.

Results:

The in vitro study showed 10.67% green tea release at 30 min; thereafter, a slow release was noted till 120 min.

In vivo study:

Both groups showed significant reduction in GI scores at the test sites. Group 1 showed significant (P < 0.001) PPD reduction at different time intervals at the test sites. However, group 2 showed significant reduction from baseline (5.30 ± 0.70) to fourth week (3.5 ± 0.97). Statistically significant gain in CAL at the test sites was observed both in group 1 (1.33 mm) and group 2 (1.43 mm). The prevalence of P. gingivalis in group 1 test sites was significantly reduced from baseline (75%) to fourth week (25%).

Conclusions:

Local drug delivery using green tea extract could be used as an adjunct in the treatment of chronic periodontitis in diabetic and non-diabetic individuals.

Release of metronidazole from electrospun poly(L-lactide-co-D/L-lactide) fibers for local periodontitis treatment

OBJECTIVES

We aimed to achieve detailed biomaterials characterization of a drug delivery system for local periodontitis treatment based on electrospun metronidazole-loaded resorbable polylactide (PLA) fibers.

METHODS

PLA fibers loaded with 0.1-40% (w/w) MNA were electrospun and were characterized by SEM and DSC. HPLC techniques were used to analyze the release profiles of metronidazole (MNA) from these fibers. The antibacterial efficacy was determined by measuring inhibition zones of drug-containing aliquots from the same electrospun fiber mats in an agar diffusion test. Three pathogenic periodontal bacterial strains: Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were studied. Cytotoxicity testing was performed with human gingival fibroblasts by: (i) counting viable cells via live/dead staining methods and (ii) by exposing cells directly onto the surface of MNA-loaded fibers.

RESULTS

MNA concentration influenced fiber diameters and thus w/w surface areas: diameter being minimal and area maximal at 20% MNA. HPLC showed that these 20% MNA fibers had the fastest initial MNA release. From the third day, MNA release was slower and nearly linear with time. All fiber mats released 32-48% of their total drug content within the first 7 days. Aliquots of media taken from the fiber mats inhibited the growth of all three bacterial strains. MNA released up to the 28th day from fiber mats containing 40% MNA significantly decreased the viability of F. nucleatum and P. gingivalis and up to the 2nd day also for the resistant A. actinomycetemcomitans. All of the investigated fibers and aliquots showed excellent cytocompatibility.

SIGNIFICANCE

This study shows that MNA-loaded electrospun fiber mats represent an interesting class of resorbable drug delivery systems. Sustained drug release properties and cytocompatibility suggest their potential clinical applicability for the treatment of periodontal diseases.

Metronidazole-loaded bioabsorbable films as local antibacterial treatment of infected periodontal pockets

BACKGROUND

Periodontal disease is infectious in nature and leads to an inflammatory response. It arises from the accumulation of subgingival bacterial plaque and leads to the loss of attachment, increased probing depth, and bone loss. It is one of the world's most prevalent chronic diseases. In this study we developed and studied metronidazole-loaded 50/50 poly(DL-lactide-co-glycolide) (PDLGA), 75/25 PDLGA, and poly(DL-lactic acid) (PDLLA) films. These films are designed to be inserted into the periodontal pocket and treat infections with controlled-release metronidazole for >or=1 month.

METHODS

The structured films were prepared using the solution-casting technique. Concentrated solutions and high solvent-evaporation rates were used to get most of the drug located in the bulk, i.e., in whole film's volume. The effects of copolymer composition and drug content on the release profile, cell growth, and bacterial inhibition were investigated.

RESULTS

The PDLLA and 75/25 PDLGA films generally exhibited a low- or medium-burst release followed by a moderate release at an approximately constant rate, whereas the 50/50 PDLGA films exhibited a biphasic release profile. The drug released from films loaded with 10% weight/weight metronidazole resulted in a significant decrease in bacterial viability within several days. When exposed to human gingival fibroblasts in cell culture conditions, these films maintained their normal fibroblastic features.

CONCLUSIONS

This study enabled the understanding of metronidazole-release kinetics from bioabsorbable polymeric films. The developed systems demonstrated good biocompatibility and the ability to inhibit Bacteroides fragilis growth; therefore, they may be useful in the treatment of periodontal diseases.

Recent approaches for the treatment of periodontitis

Periodontal disease is a localised inflammatory response caused by the infection of a periodontal pocket arising from the accumulation of subgingival plaque. Periodontal disease has been considered as a possible risk factor for other systemic diseases such as cardiovascular diseases and pre-term low birth weight infants. Advances in understanding the aetiology, epidemiology and microbiology of periodontal pocket flora have revolutionised the therapeutic strategies for the management of periodontal disease progression. This review summarises the recent developments in the field of intra-pocket drug delivery systems and identifies areas where further research may lead to a clinically effective intra-pocket delivery system.

In vitro studies on controlled-release cellulose acetate films for local delivery of chlorhexidine, indomethacin, and meloxicam

BACKGROUND

Delivery of medications into periodontal pockets to suppress or eradicate the pathogenic microbiota or modulate the inflammatory response, thereby limiting periodontal tissue destruction, has attracted significant interest with the purpose of effective periodontal treatment. However, no study has previously attempted to develop a controlled-release formulation of anti-inflammatory agents to be used in the field of periodontology. The aim of the present study was to examine the in vitro release profile of chlorhexidine gluconate, indomethacin, and meloxicam from cellulose acetate films.

METHODS

Cellulose acetate films containing chlorhexidine gluconate, indomethacin, and meloxicam were prepared and cut in a form to fit to the periodontal pocket anatomy. The release of active agents was studied in 10 ml artificial saliva at 37 degrees C. Apparatus Vibrax was used at 150 r.p.m. Determinations were carried out spectrophotometrically and the release profiles were plotted as a function of time.

RESULTS

The formulations showed two different release patterns for a total observation period of approximately 120 h. When the formulations of the three active agents were compared, the release patterns of meloxicam and chlorhexidine gluconate were found to be similar, while the indomethacin-containing formulation exhibited the fastest release rate.

CONCLUSIONS

As a conclusion, cellulose acetate may be a suitable inert material for obtaining a prolonged local release of various anti-inflammatory agents like meloxicam. Further in vitro and in vivo studies are required before starting clinical applications of these controlled-release formulations of anti-inflammatory agents.

Effect of a controlled-release chlorhexidine chip on clinical and microbiological parameters of periodontal syndrome

AIM

The aim of this study was to evaluate the effectiveness of a controlled-released chlorhexidine chip (CHX) as adjunctive therapy to scaling and root planing (SRP) in the treatment of chronic periodontitis.

MATERIAL AND METHODS

Twenty patients with at least four sites with probing depth >or= 5 mm and bleeding on probing were selected. This randomized single-blind study was carried out in parallel design. The control group received SRP alone, while the test group received SRP plus CHX chip. The clinical parameters, Plaque Index (PlI), Papillary Bleeding Score (PBS), Bleeding on Probing (BOP), Gingival Recession (GR), Probing Depth (PD) and Relative Attachment Level (RAL), and the microbiological parameter BANA test were recorded at baseline and after 3, 6 and 9 months.

RESULTS

Both groups presented significant improvements in all parameters analyzed over the study period. There were no statistically significant differences between the two groups for any parameter analyzed after 9 months, except for BOP, which was significantly reduced in the control group. The mean reductions on PD and RAL were 2.4 mm and 1.0 mm for the control group and 2.2 mm and 0.6 mm for the test group, respectively.

CONCLUSION

The CHX chip did not provide any clinical or microbiological benefit beyond that achieved with conventional scaling and root planning, after a 9-month period.

Biodegradable injectable in situ forming drug delivery systems

The ability to inject a drug incorporated into a polymer to a localized site and have the polymer form a semi-solid drug depot has a number of advantages. Among these advantages is ease of application and localized, prolonged drug delivery. For these reasons a large number of in situ setting polymeric delivery systems have been developed and investigated for use in delivering a wide variety of drugs. In this article we introduce the various strategies that have been used to prepare in situ setting systems, and outline their advantages and disadvantages as localized drug delivery systems.

Triggered release of calcium from lipid vesicles: a bioinspired strategy for rapid gelation of polysaccharide and protein hydrogels

The bioinspired strategy of triggered release of Ca2+ from liposomal compartments was used to induce rapid gelation of polysaccharide and protein-based hydrogels. Thermally triggerable liposomes were designed by entrapping CaCl2 within liposomes constructed of 90% dipalmitoylphosphatidylcholine and 10% dimyristoylphosphatidylcholine. These liposomes released greater than 90% of entrapped Ca2+ when heated to 37 degrees C. A precursor fluid containing liposomes suspended in aqueous sodium alginate remained fluid for several days at room temperature but gelled rapidly when heated to 37 degrees C, as a result of Ca2+ release and formation of crosslinked Ca-alginate. Alternatively, thermally triggered Ca2+ release from liposomes was used to activate enzyme-catalyzed crosslinking of proteins to form hydrogels. A mixture of Ca-loaded liposomes, fibrinogen, and a Ca2+-dependent transglutaminase enzyme (either human recombinant FXIII or guinea pig liver transglutaminase) remained fluid indefinitely when stored at room temperature, but gelled rapidly when heated to 37 degrees C. SDS-PAGE of the reaction mixture revealed that gelation was due to enzymatic crosslinking of the alpha and gamma chains of fibrinogen, and oscillating rheometry revealed gel formation within 10 min of heating to 37 degrees C. This new approach may be useful for developing rapidly gelling injectable biomaterials that can be stored at room temperature and injected in a minimally invasive manner into a body tissue or cavity, upon which rapid solidification would occur. This versatile bioinspired strategy could be utilized for the delivery of biomaterials for tissue repair and reconstruction, and local site-directed drug delivery.

The antimicrobial treatment of periodontal disease: changing the treatment paradigm

Over the last 100 years, methods of surgical periodontal treatment have enjoyed a history of success in improving oral health. The paradigm of care is based on the "non-specific plaque hypothesis"--that is, the overgrowth of bacterial plaques cause periodontal disease, and the suppression of this overgrowth reduces disease risk. The central feature of this approach to care is the removal of inflamed gingival tissue around the teeth to reduce periodontal pocket depth, thereby facilitating plaque removal by the dentist and by the patient at home. Over the last 30 years, with the recognition that periodontal disease(s) is caused by specific bacteria and that specific antimicrobial agents can reduce or eliminate the infection, a second paradigm has developed. This new paradigm, the "specific plaque hypothesis", focuses on reducing the specific bacteria that cause periodontal attachment loss. The contrast between the two paradigms can be succinctly stated as follows: The antimicrobial therapy reduces the cause, while the surgical therapy reduces the result of the periodontal infection. The specific plaque hypothesis has two important implications. First, with the increasing attention to evidence-based models for prevention, treatment, outcome assessment, and reimbursement of care, increasing attention and financial effort will be channeled into effective preventive and treatment methods. Second, the recent observations that periodontal infections increase the risk of specific systemic health problems, such as cardiovascular disease, argue for the prevention and elimination of these periodontal infections. This review highlights some of the evidence for the specific plaque hypothesis, and the questions that should be addressed if antimicrobial agents are to be used responsively and effectively.

Controlled and targeted drug delivery strategies towards intraperiodontal pocket diseases

Advances in the understanding of the aetiology, epidemiology, pathogenesis and microbiology of periodontal pocket flora have revolutionized the strategies for the management of intraperiodontal pocket diseases. Intra-pocket, sustained release, drug delivery devices have been shown to be clinically effective in the treatment of periodontal infections. Several degradable and non-degradable devices are under investigation for the delivery of antimicrobial agents into the periodontal pocket including non-biodegradable fibres, films (biodegradable and non-biodegradable), bio-absorbable dental materials, biodegradable gels/ointments, injectables and microcapsules. With the realization that pocket bacteria accumulate as biofilms, studies are now being directed towards eliminating/killing biofilm concentrations rather than their planktonic (fluid phase) counterparts. Intraperiodontal pocket drug delivery has emerged as a novel paradigm for the future research. Similarly, bioadhesive delivery systems are explored that could significantly improve oral therapeutics for periodontal disease and mucosal lesions. A strategy is to target a wide range of molecular mediators of tissue destruction and hence arrest periodontal disease progression. Research into regenerating periodontal structures lost as a result of disease has also shown substantial progress in the last 25 years.

Controlled delivery of inductive proteins, plasmid DNA and cells from tissue engineering matrices

It has been estimated that half the annual health care budget in the United States is spent on patients suffering from tissue loss and late stage organ failure. Critical limitations inherent in traditional therapies call for novel tissue and organ replacement strategies. This paper discusses development of biomaterials for conductive, inductive and cell-based tissue replacement strategies. Biodegradable polymer scaffolds can be used as space-filling matrices for tissue development and barriers to migration of epithelial cells in tissue conductive approaches. Inductive approaches involve sustained delivery of bioactive factors, such as protein growth factors and DNA, to alter cell function in localized regions. Factors can be released from highly porous polymer scaffolds to allow factor delivery and tissue development to occur in concert. Cell-based approaches involve seeding of cells onto polymeric scaffolds in vitro and subsequent transplantation of the scaffold. New scaffold materials are being developed that address specific tissue engineering design requirements, and in some cases attempt to mimic natural extracellular matrices. These strategies together offer the possibility of predictably forming specific tissue structures, and may provide solutions to problems such as periodontal ligament detachment, alveolar bone resorption and furcation defects.

The role of local drug delivery in the management of periodontal diseases: a comprehensive review

This review article evaluates the role of local drug delivery systems in the management of periodontal diseases. The efficacy of several local delivery devices (i.e., tetracycline fibers, metronidazole and minocycline gels, chlorhexidine chips, and doxycycline polymer) which are either commercially available in the United States or abroad, or are currently under consideration for Food and Drug Administration (FDA) approval are discussed. The drug delivery systems are assessed with regard to their functional characteristics, effectiveness as a monotherapy, as compared to scaling and root planing, and ability to enhance conventional therapy. Furthermore, controversies associated with local delivery are addressed (e.g., induction of bacterial resistant strains, the efficacy of systemic versus local drug delivery, and whether local drug delivery should function as an alternative or as an adjunct to conventional treatment).