A new degradable controlled release device for treatment of periodontal disease: in vitro release study

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.

Local Delivery and Controlled Release Drugs Systems: A New Approach for the Clinical Treatment of Periodontitis Therapy

Periodontitis is an inflammatory disease of the gums characterized by the degeneration of periodontal ligaments, the formation of periodontal pockets, and the resorption of the alveolar bone, which results in the destruction of the teeth's supporting structure. Periodontitis is caused by the growth of diverse microflora (particularly anaerobes) in the pockets, releasing toxins and enzymes and stimulating the immune system. Various approaches, both local and systemic, have been used to treat periodontitis effectively. Successful treatment depends on reducing bacterial biofilm, bleeding on probing (BOP), and reducing or eliminating pockets. Currently, the use of local drug delivery systems (LDDSs) as an adjunctive therapy to scaling and root planing (SRP) in periodontitis is a promising strategy, resulting in greater efficacy and fewer adverse effects by controlling drug release. Selecting an appropriate bioactive agent and route of administration is the cornerstone of a successful periodontitis treatment plan. In this context, this review focuses on applications of LDDSs with varying properties in treating periodontitis with or without systemic diseases to identify current challenges and future research directions.

Advanced Drug Delivery Platforms for the Treatment of Oral Pathogens

The oral cavity is a complex ecosystem accommodating various microorganisms (e.g., bacteria and fungi). Various factors, such as diet change and poor oral hygiene, can change the composition of oral microbiota, resulting in the dysbiosis of the oral micro-environment and the emergence of pathogenic microorganisms, and consequently, oral infectious diseases. Systemic administration is frequently used for drug delivery in the treatment of diseases and is associated with the problems, such as drug resistance and dysbiosis. To overcome these challenges, oral drug delivery systems (DDS) have received considerable attention. In this literature review, the related articles are identified, and their findings, in terms of current therapeutic challenges and the applications of DDSs, especially nanoscopic DDSs, for the treatment of oral infectious diseases are highlighted. DDSs are also discussed in terms of structures and therapeutic agents (e.g., antibiotics, antifungals, antiviral, and ions) that they deliver. In addition, strategies (e.g., theranostics, hydrogel, microparticle, strips/fibers, and pH-sensitive nanoparticles), which can improve the treatment outcome of these diseases, are highlighted.

Gradual Drug Release Membranes and Films Used for the Treatment of Periodontal Disease

Periodontitis is an inflammatory disease that, if not treated, can cause a lot of harm to the oral cavity, to the patients' quality of life, and to the entire community. There is no predictable standardized treatment for periodontitis, but there have been many attempts, using antibiotics, tissue regeneration techniques, dental scaling, or root planning. Due to the limits of the above-mentioned treatment, the future seems to be local drug delivery systems, which could gradually release antibiotics and tissue regeneration inducers at the same time. Local gradual release of antibiotics proved to be more efficient than systemic administration. In this review, we have made a literature search to identify the articles related to this topic and to find out which carriers have been tested for drug release as an adjuvant in the treatment of periodontitis. Considering the inclusion and exclusion criteria, 12 articles were chosen to be part of this review. The selected articles indicated that the drug-releasing carriers in periodontitis treatment were membranes and films fabricated from different types of materials and through various methods. Some of the drugs released by the films and membranes in the selected articles include doxycycline, tetracycline, metronidazole, levofloxacin, and minocycline, all used with good outcome regarding their bactericide effect; BMP-2, Zinc-hydroxyapatite nanoparticles with regenerative effect. The conclusion derived from the selected studies was that gradual drug release in the periodontal pockets is a promising strategy as an adjuvant for the treatment of periodontal disease.

Local drug delivery systems as therapeutic strategies against periodontitis: A systematic review

Periodontitis is a chronic inflammation of the soft tissue surrounding and supporting the teeth, which causes periodontal structural damage, alveolar bone resorption, and even tooth loss. Its prevalence is very high, with nearly 60% of the global population affected. Hence, periodontitis is an important public health concern, and the development of effective healing treatments for oral diseases is a major target of the health sciences. Currently, the application of local drug delivery systems (LDDS) as an adjunctive therapy to scaling and root planning (SRP) in periodontitis is a promising strategy, giving higher efficacy and fewer side effects by controlling drug release. The cornerstone of successful periodontitis therapy is to select an appropriate bioactive agent and route of administration. In this context, this review highlights applications of LDDS with different properties in the treatment of periodontitis with or without systemic diseases, in order to reveal existing challenges and future research directions.

Current status and future of delivery systems for prevention and treatment of infections in the oral cavity

Oral health reflects the general health, and it is fundamental to well-being and quality of life. An infection in the oral cavity can be associated with serious complications in human health. Local therapy of these infections offers many advantages over systemic drug administration, targeting directly to the diseased area while minimizing systemic side effects. Specialized drug delivery systems into the oral cavity have to be designed in such a fashion that they resist to the aqueous environment that is constantly bathed in saliva and subject to mechanical forces. Additionally, a prolonged release of drug should also be provided, which would enhance the efficacy and also decrease the repeated dosing. This review is aimed to summarize the current most relevant findings related to local drug delivery of various drug groups for prevention and treatment of infections (viral, bacterial, fungal) and infection-related manifestations in the oral cavity. Current therapeutic challenges in regard to effective local drug delivery systems will be discussed, and the recent approaches to overcome these obstacles will be reviewed. Finally, future prospects will be overviewed to promote novel strategies that can be implemented in clinical management for prevention and treatment of oral infections.

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.

Sustained-release delivery of antimicrobial drugs for the treatment of periodontal diseases: Fantasy or already reality?

Periodontal diseases are prevalent in humans. Conventional means of combating these diseases involve basic oral hygiene, mostly toothbrushing, use of mouthwashes, and flossing. Supplementary means of treatment, either clinical or pharmaceutical, are often necessary. The use of sustained-release delivery systems, applied locally to the periodontal pocket, seems to be one feasible approach: local sustained-release delivery of antibacterial agents to treat periodontal diseases is conceivable. The use of local (intrapocket) sustained-release delivery systems has numerous clinical, pharmacologic, and toxicologic advantages over conventional treatments for periodontal diseases. Sustained-release technology has been proven to be effective over the last few decades. Films, gels, and fibers are the three main classical intrapocket pharmaceutical delivery systems. Research today is more focused on improving drug delivery, and less on introducing new drugs. New approaches, eg, those making use of nanotechnology, are emerging for local drug-delivery systems. The local sustained-release delivery system concept is innovative and a few products are already commercially available.

An Innovative Drug Delivery System Loaded with a Modified Combination of Triple Antibiotics for Use in Endodontic Applications

The objective of the current study was to introduce "Polylactic co-Glycolic Acid- (PLGA-) Coated Ceramic Microparticles" as an innovative drug delivery system, loaded with a new combination of triple antibiotics (penicillin G, metronidazole, and ciprofloxacin (PMC)) for use in endodontic treatments. Ceramic microparticles were made from β-tricalcium phosphate and hydroxyapatite and examined by "Scanning Electronic Microscope (SEM)." Then, fixed amounts of the selected antibiotics were added to a prepared PLGA solution and stirred thoroughly. Next, the prepared ceramic microparticles were dispersed completely in the drugs solution. The deposited "PMC-loaded PLGA-coated ceramic microspheres (PPCMs)" were dried and incubated in phosphate buffer saline (PBS) for 21 days. The drug release from PPCMs was quantified by a UV spectrophotometer. The antimicrobial activity of PPCMs was investigated using the "Agar Plate Diffusion Test (ADT)," "Minimum Inhibitory Concentration (MIC)," and "Minimum Bactericidal Concentration (MBC)" against Enterococcus faecalis (E. faecalis) and Aggregatibacter actinomycetemcomitans (A.a). The cell viability test (MTT) was conducted for cytotoxicity against human gingival fibroblasts. SEM micrographs of PPCMs showed spherical-like ceramic microparticles with smooth surfaces. Crystal-like antibiotic particles (chunks) were also found on PPCMs. Initial burst of antibiotics (31 µg/mL, 160 µg/mL, and 18 µg/mL for ciprofloxacin, metronidazole, and penicillin G, respectively, in the first 4 days) followed by gradual and sustained release was observed within a period of 21 days. PPCMs demonstrated pH close to normal physiological environment and antibacterial activity against E. faecalis and A.a in the first 2 days. MTT showed cell viability of more than 70% for PPCMs after 24 h and 72 h of exposure. In conclusion, PPCMs demonstrated satisfactory release of antibiotics, antibacterial activity against the selected microorganisms, and biocompatibility. Thus, PPCMs may be used to deliver modified triple antibiotics to the root canal system for use in endodontic applications.

Comparative Evaluation of Boric Acid Gel versus Chlorhexidine Gel in the Treatment of Chronic Periodontitis: Randomized, Placebo-Controlled Clinical Study

Background:

Over the years, various antimicrobials have been tried and tested in the treatment of periodontitis. Chlorhexidine (CHX) has emerged as the gold standard. In recent years, trend has shifted toward the use of agents with antibacterial, anti-inflammatory, and osteoblastic activity. Boric acid (BA) is one such agent which possess all such properties and thus been evaluated in the treatment of periodontitis.

Aim and Objective:

The aim of the study is to compare and evaluate the efficacy of 0.75% BA gel versus 1% CHX gel as an adjunct to scaling and root planing in patients with chronic periodontitis both clinically and microbiologically.

Materials and Methods:

The present study was a randomized, placebo-controlled clinical trial where 45 systemically healthy patients with chronic periodontitis were included in the study. About 15 patients each were divided into three groups, that is, Group I received BA gel, Group II received CHX gel, and Group III received placebo gel as a local drug delivery agent. Clinical parameters such as gingival index, plaque index, modified sulcus bleeding index, probing pocket depth, and clinical attachment level were evaluated at baseline and 6-month follow-up. Microbiological analysis to check for mixed anaerobic flora was done using subgingival plaque samples at baseline and 3 months after treatment.

Results:

Significant reduction was seen in all clinical parameters in both BA and CHX gel groups as compared to control group (P < 0.05). However, on comparing BA gel group with CHX gel, the results were statistically insignificant (P > 0.05).

Conclusion:

BA gel and CHX gel both were equally effective in improving the clinical and microbiologic parameters in patients with chronic periodontitis when used as a local drug delivery agent.

Local drug delivery systems in the management of periodontitis: A scientific review

Periodontitis (PD) is a microbial disease of tooth supporting tissues that results in progressive destruction of surrounding soft and hard tissues with eventual tooth mobility and exfoliation. Perioceutics, which includes the delivery of therapeutic agents via systemic and local means as an adjunct to mechanical therapy has revolutionized the arena of periodontal therapy. Selection of a right antimicrobial agent with appropriate route of drug administration is the key to successful periodontal therapy. Irrigating systems, fibers, gels, strips, films, microparticles, nanoparticles and low dose antimicrobial agents are some of the local drug delivery systems (LDDS) available in the field, which aims to deliver antimicrobial agents to sub-gingival diseased sites with minimal or no side-effects on other body sites. The present review aim to summarize the current state-of-the-art technology on LDDS in periodontal therapy ensuring the the practitioners are able to choose LDD agents which are custom made for a specific clinical condition.

Dissolution Chamber for Small Drug Delivery System in the Periodontal Pocket

Existing dissolution chambers have relatively large volume compared to the size of the periodontal pocket. A small volume dissolution method that simulates the physiological release environment for periodontal drug delivery is needed. The objectives were to construct a small, more physiologically relevant, dissolution chamber and investigate the properties of the new dissolution chamber for the assessment of sustained drug release systems in periodontal delivery. Flow-through dissolution chambers were constructed using three-dimensional (3D) printing. Drug release experiments were performed using the dissolution chamber and a commercially available long-acting periodontal insert product, PerioChip®. Similar experiments were performed under more traditional larger volume bulk solution conditions for comparison. Computer simulations and experimental results showed that drug clearance from the dissolution chamber was fast compared to drug release from the periodontal product. Drug clearance from the flow-through dissolution chamber and drug release from the sustained release product in the chamber were related to the dissolution medium flow rate and chamber volume. Drug release in the flow-through chamber was slower than that observed in bulk solution, but approached it when the medium flow rate increased. The presence of trypsin in the dissolution medium enhanced drug release from the product. A flow-through dissolution system was constructed that could evaluate drug release from a sustained release product in a small dimension environment by modifying the flow rate and composition of the dissolution medium.

Clinical efficacy of subgingivally delivered simvastatin gel in chronic periodontitis patients

Background:

Simvastatin (SMV), a new locally delivered drug of class statins, is a specific competitive inhibitor of 3-hydroxy-2-methyl-glutaryl coenzyme A reductase. Statins, besides having lipid-lowering abilities, also have pleiotropic effects like host modulation and bone regeneration. The present study was designed to investigate the effectiveness of SMV, 1.2 mg, in an indigenously prepared biodegradable controlled-release gel as an adjunct to scaling and root planing (SRP).

Materials and Methods:

A total of 60 sites, with pocket depth ≥5 mm, two from each of 30 patients after SRP, were categorized into two treatment groups, for subgingival placement of placebo (Gp 1) or SMV (Gp 2). Clinical parameters were recorded at baseline and at 1, 3 and 6 months comprising plaque index, gingival index, probing pocket depth (PPD) and clinical attachment level (CAL). The osseous changes were evaluated radiographically by measuring vertical gain, INFRA 1 and angle of the defect, INFRA 2 from baseline to 6 months.

Results:

All subjects tolerated the drug, without any post-application complication. The treatment improved the periodontal condition in both the groups but significant reductions in PPD (p= 0.04), and INFRA 1 (p= 0.000), along with gain in CAL (p= 0.02) and INFRA 2 (p= 0.000) were observed in Gp 2. In one site, an unexpected 5 mm decrease in INFRA 1 was found.

Conclusion:

Local drug delivery of SMV enhanced the beneficial effect of SRP, in pocket reduction, gain in CAL and bone fill.

In vitro behavior of poly-lactic-co-glycolic acid microspheres containing minocycline, metronidazole, and ciprofloxacin

AIM

In the present study, we aimed to fabricate poly-lactic-co-glycolic acid (PLGA) microspheres containing a mixture of three antibiotics-minocycline, metronidazole, and ciprofloxacin (MMC)-to assess their efficacy and properties.

METHODS

MMC were loaded onto PLGA biopolymer microspheres at a 1:1:1 ratio using the double emulsion technique. The morphology of microspheres was observed by a (SEM). The controlled release of antibiotics was evaluated over an 18-day period. The antibacterial efficacy of released antibiotics against Aggregatibacter actinomycetemcomitans was evaluated by measuring the diameter of the growth-inhibition zone. The cytotoxicity of MMC-containing microspheres was also evaluated and compared using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. One-way anova was used for the data analysis.

RESULTS

SEM micrographs confirmed the spherical shape and smooth surface of microspheres. The adequate release of antibiotics was observed from the microspheres within the desired time period of 16-18 days. The MMC-containing microspheres showed antibacterial activity for 11 days. Moreover, MMC-containing microspheres showed superior cell biocompatibility compared to the free mixture of the three antibiotics (P < 0.05).

CONCLUSION

Microspheres containing triple antibiotics showed good release, antibacterial activity for 11 days, and similar cell biocompatibility compared to the empty microspheres.

Clinical and microbiological efficacy of 3% satranidazole gel as a local drug delivery system in the treatment of chronic periodontitis: A randomized, controlled clinical trial

AIM

The present clinical trial was designed to investigate the effectiveness of subgingivally delivered satranidazole (SZ) gel as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis.

MATERIALS AND METHODS

Seventy subjects with probing depth (PD) ≥5 mm were selected. Thirty-five subjects each were randomly assigned to SRP + placebo (Group 1) and SRP + SZ (Group 2). The clinical outcomes evaluated were plaque index, gingival index, clinical attachment level (CAL), and PD at baseline; 1 month, 3 months, and 6 months interval. Furthermore, microbial analysis using polymerase chain reaction was done to estimate the number of sites harboring periodontopathogens.

RESULTS

Sixty four subjects were evaluated up to 6 months. At 6 months, the Group 2 resulted in greater mean reduction (4.10 mm) in PD as compared to Group 1 (1.49 mm), and also a greater mean CAL gain (4.20 mm) in Group 2 as compared to Group 1 (1.13 mm). These subjects also showed a significant reduction in the number of sites harboring periodontopathogens.

CONCLUSION

The use of 3% SZ gel, when used as an adjunct to nonsurgical periodontal therapy in subjects with periodontitis, achieved better results than initial periodontal treatment alone.

Alpha-2-Macroglobulin Levels in Gingival Crevicular Fluid Pre- and Post-scaling and Root Planing with Adjunctive Tetracycline Fibers in Chronic Periodontitis: A Randomized Controlled Trial

BACKGROUND

This split-mouth clinical study aimed to investigate levels of alpha-2-macroglobulin (a2M) in gingival crevicular fluid (GCF) of chronic periodontitis patients pre- and post-scaling and root planing (SRP) with or without adjunctive use of tetracycline fibers.

MATERIALS AND METHODS

In 30 patients of chronic periodontitis, samples of GCF were collected from the gingival sulcus before SRP. Recording of clinical parameters was conducted. This was followed by local drug delivery (LDD) of tetracycline fibers in test sites. In control sites, no LDD was done. Second samples of GCF were taken 90 days after treatment. Samples of crevicular fluid were analyzed to determine the levels of a2m.

RESULTS

A gain of clinical attachment (CAL) of 3.30 mm for SRP and LDD and for SRP alone was 1.62 mm (p < 0.001). The pocket probing depth was significantly decreased by 2.43 mm for SRP and LDD and for SRP alone was 1.61 mm (p < 0.001) after 90 days. Alpha-2-macroglobulin was significantly reduced in GCF by SRP and SRP and LDD after 90 days (p < 0.001).

CONCLUSION

Clinical and biochemical variables showed a more favorable outcome when SRP was combined with LDD of tetracycline fibers in management of patients suffering from chronic periodontitis.

Comparative evaluation of single application of 2% whole turmeric gel versus 1% chlorhexidine gel in chronic periodontitis patients: A pilot study

Aim:

To evaluate and compare the clinical effects of topical subgingival application of 2% whole turmeric gel and 1% chlorhexidine gel as an adjunct to scaling and root planing (SRP) in patients suffering from chronic periodontitis.

Materials and Methods:

Fifteen patients with localized or generalized chronic periodontitis with a pocket depth of 5-7 mm were selected. In each patient, on completion of SRP, three non-adjacent sites in three different quadrants were randomly divided into three different groups, that is, Group I: Those receiving 2% turmeric gel, Group II: Those receiving 1% chlorhexidine gel (Hexigel), and Group III: SRP alone (control site). Plaque index, gingival index, probing depth, and clinical attachment levels were determined at baseline, 30 days, and 45 days.

Results:

Group II as a local drug system was better than Group III. Group I showed comparable improvement in all the clinical parameters as Group II.

Conclusions:

The experimental local drug delivery system containing 2% whole turmeric gel helped in reduction of probing depth and gain of clinical attachment levels.

Ampicillin-ester bonded branched polymers: characterization, cyto-, genotoxicity and controlled drug-release behaviour

The development and characterization of novel macromolecular conjugates of ampicillin using branched biodegradable polymers has been described in this study. The conjugates have been prepared coupling the β-lactam antibiotic with branched polymer matrices based on the natural oligopeptide core. The cyto- and genotoxicity of the synthesized polymers were evaluated with a bacterial luminescence test, two protozoan assays and Salmonella typhimurium TA1535. The presence of a newly formed covalent bond between the drug and the polymer matrices was confirmed by ¹H-NMR and FTIR studies. A drug content (15.6 and 10.2 mole %) in the macromolecular conjugates has been determined. The obtained macromolecular products have been subjected to further in vitro release studies. The total percentage of ampicillin released after 21 days of incubation was nearly 60% and 14% and this resulted from the different physicochemical properties of the polymeric matrices. This is the first report on the application of branched biodegradable polymeric matrices for the covalent conjugation of ampicillin. The obtained results showed that the synthesized macromolecular drug-conjugates might slowly release the active drug molecule and improve the pharmacokinetics of ampicillin.

In situ forming implants for periodontitis treatment with improved adhesive properties

Novel in situ forming implants are presented showing a promising potential to overcome one of the major practical hurdles associated with local periodontitis treatment: limited adhesion to the surrounding tissue, resulting in accidental expulsion of at least parts of the implants from the patients' pockets. This leads to high uncertainties in the systems' residence times at the site of action and in the resulting drug exposure. In the present study, the addition of different types and amounts of plasticizers (acetyltributyl citrate and dibutyl sebacate) as well as of adhesive polymers (e.g., cellulose derivatives such as hydroxypropyl methylcellulose) is shown to allow for a significant increase in the stickiness of poly(lactic-co-glycolic acid)-based implants. The systems are formed in situ from N-methyl pyrrolidone-based liquid formulations. Importantly, at the same time, good plastic deformability of the implants can be provided and desired drug release patterns can be fine-tuned using several formulation tools. The antimicrobial activity of this new type of in situ forming implants, loaded with doxycycline hyclate, was demonstrated using the agar well diffusion method and multiple Streptococcus strains isolated from the oral microflora of patients suffering from periodontitis.

Effect of Thermosetting Gel with Doxycycline Hyclate 3% + Ketorolac Tromethamine 0.5% on Postoperative Discomfort after Third Molar Surgery: A Prospective Randomized Study

This study compared the analgesic and anti-inflammatory efficacy of intra-alveolar administration of a thermosetting gel containing Doxycycline Hyclate 3% + Ketorolac Tromethamine 0.5% (Tg-DHKT) (Thermosetting gel, Monteresearch, Bollate, Italy) on patient discomfort after third molar surgery. This study was a single-blind, randomized clinical trial, including two study groups of 39 and 41 patients each, who required surgical removal of a single mandibular impacted third molar. After the extraction the test group received an intra-alveolar injection with Tg-DHKT and the second group a thermosetting gel containing only Doxycycline Hyclate 3% (Tg-DH). Each patient's symptoms (pain, swelling, reddening, bleeding and body temperature) was assessed with a follow-up questionnaire (PoSSe scale). Nimesulide 100 mg, a painkiller, every 8 hours was prescribed to the Control and Test groups if necessary (maximum 3 doses); if they needed to assume it they were asked to mark it on the questionnaire. Results showed that on the second day after surgery pain, oedema and reddening decreased faster in the Control group (Tg-DH). There was no difference between the two groups when postoperative bleeding was evaluated. In both groups bleeding decreased in the same way, probably due to the mechanical characteristics of the gel itself. 46% of patients of the Test group did not require to take any painkiller at home. Our data demonstrate that the use of Tg-DHKT is less effective in the prevention of postoperative symptoms after third molar extraction compared to Tg-DH. However, almost half of patients in the Test group did not need to take more pain medication at home, suggesting that a single postoperative local administration of Tg-DHKT is a safe and effective concept for controlling pain, oedema and inflammation after third molar extraction.

Effect of local application of tea tree (Melaleuca alternifolia) oil gel on long pentraxin level used as an adjunctive treatment of chronic periodontitis: A randomized controlled clinical study

Background:

Conventional non-surgical periodontal therapy has been proven to be an effective treatment for patients with chronic periodontitis. Tea tree oil (TTO) can be used as adjunct to conventional periodontal therapy in patient with chronic periodontitis. The aim of this study was to evaluate the effectiveness of adjunctive treatment of TTO on the clinical parameters and the level of pentraxin-3 (PTX3) in chronic periodontitis.

Materials and Methods:

A total of 40 patients with moderate to severe chronic periodontitis were divided into two groups, Group I received scaling and root planing (SRP) only, Group II received SRP and TTO gel. Clinical parameters were recorded and gingival crevicular fluid (GCF) samples were collected from each subject for measuring PTX3 levels at baseline, 1, 3 and 6 months after treatment.

Results:

In all evaluation periods, there was statistically significant reduction in each of the studied clinical parameters and PTX3 level in Group II as compared with Group I.

Conclusions:

The local delivery of TTO gel in case of chronic periodontitis may have some beneficial effects to augment the results of the conventional periodontal therapy. Moreover, it places a focus on the value of monitoring GCF levels of PTX3 as a marker of periodontal tissue healing.

Kinetics of drug release from a biodegradable local drug delivery system and its effect on Porphyromonas gingivalis isolates: An in vitro study

BACKGROUND

Conventional anti-microbial therapy largely consisted of systemic administration of various drugs effective against periodontal pathogens, but fraught with several problems. Based on the concept of local drug delivery a bioresorbable device made of pure fibrillar collagen has been developed. The aim of this study was to study the release of Tetracycline from this collagen fiber (Type I collagen) impregnated with Tetracycline and its antibacterial activity against Porphyromonas gingivalis.

MATERIALS AND METHODS

Porphyromonas gingivalis was isolated from plaque samples of chronic periodontitis patients by using a CO2 incubator. DNA isolation was done followed by polymerase chain reaction (PCR) amplification to confirm the presence of bacteria. The release pattern of Tetracycline was assessed for a period of 10 days in water (group I) and Serum inoculated with Porphyromonas gingivalis (group II).

RESULTS

A significant presence of Tetracycline on all days in Group I and group II and the zone of inhibition was also present in both groups with a steady decline from day 1 to day 10.

CONCLUSION

Since the results were well within the therapeutic concentration of drug required to inhibit the growth of gram -ve bacteria (Porphyromonas gingivalis), this bioresorbable Tetracycline fiber has the potential for clinical application.

Local drug delivery of 0.5% azithromycin in the treatment of chronic periodontitis among smokers

BACKGROUND

Along with conventional periodontal surgical therapy, local delivery of antibiotics may provide more effective treatment in smokers by targeting tissue-invasive bacteria. The aim of this randomized, placebo-controlled, double-masked clinical trial was to evaluate the adjunctive effects of subgingivally delivered 0.5% azithromycin (AZM) as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis in smokers.

METHODS

Fifty-four patients were randomized and categorized into two treatment groups: Group 1 - 26 subjects who received (SRP) plus placebo gel and Group 2 - 28 subjects who received (SRP) plus 0.5% azithromycin. Clinical parameters were recorded at baseline, 3, 6 and 9 months. They included Plaque Index (PI), modified Sulcus Bleeding Index (mSBI), probing depth (PD) and clinical attachment level (CAL).

RESULTS

Azithromycin resulted in significant improvements. A single application of AZM resulted in attachment gain at 9 months of 2.44 ± 0.64 mm as compared to 0.18 ± 0.68 mm for the placebo. Similarly, pocket depth and PI were significantly reduced but no change in the mSBI was noted.

CONCLUSIONS

When compared to the placebo, the adjunctive use of 0.5% AZM resulted in significant improvement in clinical outcome in the treatment of chronic periodontitis among smokers.

Locally delivered 0.5% clarithromycin, as an adjunct to nonsurgical treatment in chronic periodontitis with well-controlled type 2 diabetes: a randomized controlled clinical trial

OBJECTIVE

Several epidemiologic studies have identified a greater incidence of periodontitis in patients with type 2 diabetes. Recent developments suggest that local delivery of antimicrobials into periodontal pockets improve periodontal health. The present study was designed to investigate the adjunctive effects of subgingivally delivered clarithromycin (CLM) (0.5% concentration) as an adjunct to scaling and root planing for treating chronic periodontitis in patients with well-controlled type 2 diabetes.

METHODS

Sixty-three patients were categorized into two treatment groups: Group 1, scaling and root planing (SRP) plus 0.5% CLM; Group 2, SRP plus placebo gel. Clinical parameters were recorded at baseline, 1, 2, and 3 months; which included gingival index (GI), sulcus bleeding index (SBI), plaque index (PI), probing depth (PD), and periodontal attachment level (PAL).

RESULTS

Both therapies resulted in significant improvements. Using a subject-based analysis, patients in Group 1 treated with SRP + CLM showed enhanced reductions in PI, GI, SBI, and PD, and gains in PAL (P < 0.001) over a period of 6 months as compared to Group 2.

CONCLUSION

Although both treatment strategies seemed to benefit the patients, the adjunctive use of 0.5% CLM as a controlled drug delivery system enhanced the clinical outcome.

Treatment modalities and evaluation models for periodontitis

Periodontitis is the most common localized dental inflammatory disease related with several pathological conditions like inflammation of gums (gingivitis), degeneration of periodontal ligament, dental cementum and alveolar bone loss. In this perspective, the various preventive and treatment modalities, including oral hygiene, gingival irrigations, mechanical instrumentation, full mouth disinfection, host modulation and antimicrobial therapy, which are used either as adjunctive treatments or as stand-alone therapies in the non-surgical management of periodontal infections, have been discussed. Intra-pocket, sustained release systems have emerged as a novel paradigm for the future research. In this article, special consideration is given to different locally delivered anti-microbial and anti inflammatory medications which are either commercially available or are currently under consideration for Food and Drug Administration (FDA) approval. The various in vitro dissolution models and microbiological strain investigated to impersonate the infected and inflamed periodontal cavity and to predict the in vivo performance of treatment modalities have also been thrashed out. Animal models that have been employed to explore the pathology at the different stages of periodontitis and to evaluate its treatment modalities are enlightened in this proposed review.

Locally Delivered 0.5% Azithromycin as an Adjunct to Non-Surgical Treatment in Patients With Chronic Periodontitis With Type 2 Diabetes: A Randomized Controlled Clinical Trial

BACKGROUND

Several epidemiologic studies have identified a greater incidence of periodontitis in patients with type 2 diabetes. Recent developments suggest that local delivery of antimicrobials into periodontal pockets improve periodontal health. The present study is designed to investigate the adjunctive effects of subgingivally delivered azithromycin (AZM; 0.5% concentration) as an adjunct to scaling and root planing (SRP) for treating chronic periodontitis in patients with type 2 diabetes.

METHODS

A total of 63 patients were categorized into two treatment groups: 1) group 1: SRP + placebo gel and 2) group 2: SRP + 0.5% AZM. Clinical parameters were recorded at baseline and 3, 6, and 9 months; they included modified sulcus bleeding index (mSBI), plaque index (PI), probing depth (PD), and clinical attachment level (CAL).

RESULTS

Both therapies resulted in significant improvements. Using a patient-based analysis, patients in group 2 treated with SRP + 0.5% AZM showed enhanced reductions in PI, GI, mSBI, and PD and gains in CAL (P <0.05) over 9 months compared with group 1.

CONCLUSION

Although both treatment strategies seem to benefit the patients, the adjunctive use of 0.5% AZM as a controlled drug delivery system enhances the clinical outcome.

To assess the effectiveness of a chlorhexidine chip in the treatment of chronic periodontitis: A clinical and radiographic study

CONTEXT

Controlled local delivery of disinfecting agents has been demonstrated to be efficient in improving the outcome of periodontal therapy.

AIMS

The aim of the present study was to evaluate the efficacy of a controlled-release biodegradable chlorhexidine chip (Periocol CG) when used as an adjunct to scaling and root planing in the treatment of periodontitis.

SETTINGS AND DESIGN

The study was carried out as randomized controlled two-group parallel clinical trial.

MATERIALS AND METHODS

Forty patients in the age group of 30-65 years suffering from mild to moderate chronic periodontitis, having pocket depth ranging between 5 and 8 mm, were selected for the study. At the screening visit, complete history taking, periodontal examination and full-mouth supragingival scaling was carried out for each patient. At the baseline visit (on the 7(th) day), all clinical parameters and radiographic parameters were recorded at selected sites and patients were randomly assigned to either the control group (group A) or the treatment group (group B). All patients in both the groups received complete subgingival scaling and root planing. Then, in group B, chlorhexidine chip (Periocol CG) was inserted at the selected site. Patients were recalled at 1 month, 2 months and 3 months from the baseline for recording clinical observations, and radiographic parameters were recorded at the end of the study.

STATISTICAL ANALYSIS

Mean, standard deviation, Chi-square test, "t" test for equality of means and paired samples correlations were used.

RESULTS

There was a statistically significant clinical attachment gain, reduction in bleeding index scores, probing pocket depth reduction and bone gain in both the groups, but group B showed better results than group A, and these differences were statistically significant.

CONCLUSIONS

The results of this study show that chlorhexidine chip (PerioCol-CG) is an effective adjunctive therapy to scaling and root planing in the treatment of chronic periodontitis.

Adsorption of nicotinic acid on the surface of nanosized hydroxyapatite and structurally modified hydroxyapatite

In the present paper, hydroxyapatite and structurally modified hydroxyapatite were investigated to establish the best material for nicotinic acid adsorption. Structurally modified hydroxyapatite wa prepared by adding sodium silicate in the reaction medium. The influence of silica concentration, presence of small amounts of metal ions, temperature and initial concentrations of nicotinic acid solutions on the adsorption capacity, were studied. Results indicated that structurally modified hydroxyapatite doped with copper adsorbed the highest amount of nicotinic acid. For this material the adsorption capacity was 0.232 mg nicotinic acid / g material, at an initial concentration of 10−4 M nicotinic acid. For all types of materials, best results were obtained at 15°C. The amount of nicotinic acid adsorbed increases with the decrease in temperature and with the increase in the initial concentration of nicotinic acid. Adsorption kinetics data were modeled using pseudo-first and pseudo-second order models while the interference due to diffusion was analyzed with intraparticle diffusion model. The results indicate that pseudo-second order model best describes the adsorption kinetics data, indicating the formation of chemical bonding.

The materials used in this study were characterized by the following methods: IR, Coulter Counter analyzer, Scanning Electron Microscope and BET

Effect of zein on biodegradable inserts for the delivery of tetracycline within periodontal pockets

Treatment with antibiotics within the periodontal pocket against bacterial infections represents a useful and adjunctive tool to conventional therapy for healing and teeth preservation. With this function in view, an implantable, tetracycline delivery device for the treatment of periodontal disease was developed. The aim of this study was to develop biodegradable, tetracycline-loaded microparticles made of two polymers: PLGA and zein which were compressed into monolithic devices. In this polymer delivery system, the encapsulation efficiency, release characteristics, drug–polymer interaction, and antibacterial activity of loaded drug were investigated. The interaction of tetracycline with the corn protein zein was studied by nuclear magnetic resonance (NMR), Fourier transform infrared, and X-ray diffraction. The hydrophobic interaction of tetracycline with zein in the formulations was deduced from the NMR studies, whereas X-ray diffraction studies showed a new crystalline state of the drug in the presence of the protein. Zein was not denatured by preparation of inserts. Sustained release of tetracycline was obtained, and the proportion of zein in the inserts had a great impact on the drug release. Finally, an effective tetracycline release from inserts against Staphylococcus aureus was achieved over 30 days. In conclusion, the PLGA:zein delivery system described in this study was found to be effective in controlled delivery of tetracycline, and hence may be suitable for intra-pocket delivery of antimicrobial agents in the treatment of periodontitis.

A novel approach to the use of subgingival controlled-release chlorhexidine delivery in chronic periodontitis: a randomized clinical trial

BACKGROUND

We aimed to analyze clinical, microbiologic, and serologic effects of chlorhexidine (CHX) chips used as a subgingival controlled-release delivery device before and immediately after scaling and root planing (SRP).

METHODS

Twenty-four patients presenting with ≥12 teeth with probing depth (PD) ≥5 mm and bleeding on probing were assigned in test or control groups. After prophylaxis, CHX chips (test) or placebo chips (control) were placed in pockets with PD ≥5 mm. Ten days later, SRP was performed in all teeth with PD ≥4 mm in a single appointment. Immediately after SRP, new chips were inserted in all pockets with PD ≥5 mm. Parameters were assessed at baseline; beginning of SRP; and 1, 3, and 6 months after treatment. Subgingival samples were obtained at baseline; beginning of SRP; and at 1 month after treatment. Periodontal pathogens Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola were analyzed. Serum levels of high sensitive C-reactive and lipopolysaccharide-binding proteins were measured. The changes of the parameters between and within the groups were tested by Mann-Whitney U test (P <0.05).

RESULTS

All clinical and serologic parameters improved in both groups over time. There was a significant difference in clinical attachment level (CAL) gain from baseline to 6 months between groups (1.17 mm in the test group versus 0.79 mm in the placebo group) (P <0.05). The treatment with CHX chips showed a greater reduction of the microorganisms of the "red complex" after 1 month (P = 0.02).

CONCLUSION

The use of CHX chips before and immediately after SRP improved CAL and reduced the subgingival microorganisms of the red complex in the treatment of chronic periodontitis.

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.

Clinical and microbiologic effects of subgingivally delivered 0.5% azithromycin in the treatment of chronic periodontitis

BACKGROUND

Recent developments suggest that the local delivery of antimicrobials into periodontal pockets can improve periodontal health. The present study was undertaken to investigate the clinical and microbiologic effectiveness of azithromycin (AZM) at 0.5% concentration in an indigenously prepared bioabsorbable controlled-release gel as an adjunct to non-surgical mechanical therapy in the treatment of chronic periodontitis.

METHODS

Eighty patients were categorized into two treatment groups: scaling and root planing (SRP) only (group 1) and SRP plus 0.5% AZM (group 2). Clinical parameters were recorded at baseline and 1, 2, and 3 months; they included modified gingival index, modified sulcus bleeding index, probing depth (PD), and clinical attachment level (CAL). At baseline and 6 and 12 weeks, microbiologic assessment was done of the percentage of morphologically different microorganisms (coccoid cells, others [straight rods, filaments, and fusiforms], motile rods, and spirochetes) using darkfield microscopy. The mean concentration of 0.5% AZM in gingival crevicular fluid was estimated by reverse phase high performance liquid chromatography.

RESULTS

Both therapies resulted in significant improvements. Mean PD reduction from baseline to 3 months was 2.13 +/- 0.35 mm and 2.53 +/- 0.52 in groups 1 and 2, respectively. Mean CAL gain from baseline to 3 months was 0.60 +/- 0.63 mm and 1.07 +/- 0.70 mm in groups 1 and 2, respectively. All microbiologic categories showed significant improvement in both groups, with greater improvement in the test group. The mean concentration of AZM at all observed periods (baseline to 28 days) provided sufficient antimicrobial activity (>2 microg/ml) and fulfilled the conditions for a controlled-release device.

CONCLUSION

Although both treatment strategies seemed to benefit the patients, the adjunctive use of 0.5% AZM as a controlled drug-delivery system enhanced the clinical and microbiologic results as shown by the intergroup comparison.

Oral Bioadhesive Drug Delivery Systems

The oral mucosal cavity is a feasible, safe, and very attractive site for drug delivery with good acceptance by users. The mucosa is relatively permeable and robust, shows short recovery times after stress or damage, is tolerant to potential allergens, and has a rich blood supply. Moreover, oral mucosal drug delivery bypasses the first-pass effect and avoids presystemic elimination in the gastrointestinal tract. Bioadhesive systems provide intimate contact between a dosage form and the absorbing tissue, which may result in high concentration in a local area and hence high drug flux through the absorbing tissue. The efficacy of oral bioadhesive drug delivery systems is affected by the biological environment and the properties of the polymer and the drug. In the present paper, we review systematically some relevant citations regarding the environment, strategies for oral drug delivery and evaluation, and utilization of the main polymers.

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.

Supramolecular self-assembly of β-cyclodextrin: an effective carrier of the antimicrobial agent chlorhexidine

The supramolecular assembly between chlorhexidine and cyclomaltoheptaose (beta-cyclodextrin, betaCD) was characterized using NMR spectroscopy ((1)H, T(1), and ROESY), ESIMS and ITC. NMR data suggest the formation of high ordered complexes. ESIMS and ITC allowed the confirmation of the average stoichiometry as 1:4 and the thermodynamic data, also obtained by ITC, showed that the assembly is strongly stabilized by short distance interactions, but suffers a strong, opposite effect of entropy reduction. The antimicrobial activity of 1:1, 1:2, 1:3, and 1:4 Clx/betaCD molar ratio mixtures was investigated in aqueous solution and after incorporation into mucoadhesive gels. These were used to determine the initial and the long-term antimicrobial activity, respectively, toward Actinobacillus actinomycetemcomitans (A.a.) (Y4-FDC) and Enterococcus faecalis (E.f.) (ATCC 14508) strains. The results showed that A.a. and E.f. were more susceptible to the 1:4 molar ratio mixture in either solution or gel (p<0.05).

Semisolid systems containing propolis for the treatment of periodontal disease: in vitro release kinetics, syringeability, rheological, textural, and mucoadhesive properties

Formulations containing poloxamer 407 (P407), carbopol 934P (C934P), and propolis extract (PE) were designed for the treatment of periodontal disease. Gelation temperature, in vitro drug release, rheology, hardness, compressibility, adhesiveness, mucoadhesion, and syringeability of formulations were determined. Propolis release from formulations was controlled by the phenomenon of relaxation of polymer chains. Formulations exhibited pseudoplastic flow and low degrees of thixotropy or rheopexy. In most samples, increasing the concentration of C934P content significantly increased storage modulus (G'), loss modulus (G''), and dynamic viscosity (eta'), at 5 degrees C, G'' exceeded G'. At 25 and 37 degrees C, eta' of each formulation depended on the oscillatory frequency. Formulations showed thermoresponsive behavior, existing as a liquid at room temperature and gel at 34-37 degrees C. Increasing the C934P content or temperature significantly increased formulation hardness, compressibility, and adhesiveness. The greatest mucoadhesion was noted in the formulation containing 15% P407 (w/w) and 0.25% C934P (w/w). The work of syringeability values of all formulations were similar and very desirable with regard to ease of administration. The data obtained in these formulations indicate a potentially useful role in the treatment of periodontitis and suggest they are worthy of clinical evaluation.

Clinical Evaluation of the Use of Locally Delivered Chlorhexidine in Periodontal Maintenance Therapy

BACKGROUND

The objective of this study was to evaluate clinically the effectiveness of a chlorhexidine gluconate chip in sites still showing signs of disease during periodontal maintenance therapy.

METHODS

Forty-two maintenance non-smoking patients (previously treated with non-surgical scaling and root planing [SRP]), presenting at least one probing depth (PD) of 5 to 8 mm, and bleeding on probing (BOP) at single-rooted teeth were assigned randomly to two groups: treated with a chlorhexidine gluconate chip (CHIP group) and treated with SRP (SRP group). Patients were assessed for plaque index, gingival index, BOP, PD, clinical attachment level (CAL), and gingival recession at baseline, 6 weeks, and 3 and 6 months.

RESULTS

Both treatments resulted in improvements in all parameters evaluated. After 6 months, a reduction in PD of 2.64 +/- 0.02 mm and 2.12 +/- 0.02 mm was observed for CHIP and SRP groups, respectively (P >0.05). The observed gain in CAL was 2.19 +/- 0.87 mm and 2.07 +/- 1.53 mm for CHIP and SRP groups, respectively (P >0.05). In deep pockets, PD reduction was 3.60 +/- 0.70 mm for CHIP group and 2.83 +/- 0.62 mm for SRP group (P = 0.01).

CONCLUSIONS

Both treatments were equally effective in periodontal health reestablishment in inflamed single-root sites of maintenance patients. However, for deep pockets, the chlorhexidine gluconate chip was more effective than SRP in reducing PD.

The effect of calcium hydroxide root filling on dentin fracture strength

This in vitro study measured the effect of calcium hydroxide root filling on the microtensile fracture strength (MTFS) of teeth. A total of 40 extracted human disease-free permanent maxillary incisors were hand and rotary instrumented and vertically compacted with United States Pharmacopeia (USP) calcium hydroxide. The teeth were stored in a moist environment for 7, 28, and 84 days. As a control group, 10 teeth were vertically compacted with gutta percha and sealer. The MTFS of the teeth was measured (Mpa) using an Instron machine. Data were assessed statistically using an unpaired t-test (P value). The intracanal placement of calcium hydroxide weakened the MTFS of teeth by 13.9 Mpa per 77 days: an average of 0.157 MPa day-1. Between 7 and 84 days, the MTFS of the dentin was reduced by 43.9%. This difference was statistically significant (P < 0.05). A statistical difference (P < 0.05) was observed between the mean MTFS of the calcium hydroxide-filled dentin between 7 days (45.7 MPa) and 28 days (35.6 MPa) and also between 7 and 84 days (31.8 MPa). There was also a significant difference (P < 0.05) between the MTFS of the calcium hydroxide-filled dentin after 84 days (31.8 MPa) and the gutta percha-filled dentin (41.3 MPa) when used as a control root filling material. The weakening of the dentin by 23-43.9% following root canal filling with calcium hydroxide provides compelling evidence to re-evaluate the daily usage of this material in endodontic therapy.

Characterization, bioactivity and ampicillin release kinetics of TiO2 and TiO24SiO2 synthesized by sol-gel processing

Local drug delivery of antimicrobics by sustained release delivery system can be used to treat periodontal disease. Advantages of these systems may include maintaining high levels of antibiotic in the gingival crevicular fluid for a sustained period of time and ease of use with high patient acceptance. The materials used are TiO(2) and TiO(2)4SiO(2), mixed with sodium ampicillin, a broad-spectrum antibiotic, have been synthesized by sol-gel method. The amorphous nature of the gels was ascertained by X-ray diffraction analysis. Release kinetics in a simulated body fluid (SBF) have been subsequently investigated. The amount of sodium ampicillin released has been detected by UV-VIS spectroscopy and SEM. The release kinetics seems to occur in more than one stage. HPLC analysis has also been taken to ensure the integrity of ampicillin after the synthetic treatment. Finally, SEM micrographs and EDS analysis showed the formation of a hydroxyapatite layer on the surface of the samples soaked in SBF. Both the materials showed good release and could be used as drug delivery bioactive systems. High antimicrobial effects of samples against Escherichia coli and Streptococcus mutants were found.

A Systematic Review on the Effects of the Chlorhexidine Chip When Used as an Adjunct to Scaling and Root Planing in the Treatment of Chronic Periodontitis

BACKGROUND

Several local antimicrobial agents, such as a bioabsorbable chlorhexidine chip, have been developed to enhance the outcome of non-surgical periodontal therapy.

METHODS

Electronic (MEDLINE and Cochrane Oral Health Group Specialized Trials Register) and manual searches were performed to detect studies concerning the use of the chlorhexidine chip as an adjunct to scaling and root planing in the treatment of chronic periodontitis. Only full-text randomized controlled trials published in English up to June 2005 were included.

RESULTS

Five studies were finally selected following independent screening by two reviewers. Due to considerable heterogeneity in study design, a qualitative data analysis was performed. Multicenter studies have indicated significantly higher pocket reductions and clinical attachment gains following a combination of mechanical debridement and repeated chlorhexidine chip administration in comparison to scaling and root planing alone. However, some recent studies failed to confirm the additional value of the chlorhexidine chip. A number of interstudy disparities with respect to methodological quality and study design may account for this lack of accordance.

CONCLUSIONS

The clinical and microbiological data currently available on the chlorhexidine chip are limited and conflicting. More research is needed to elucidate the additional value of the chlorhexidine chip when used as an adjunct to scaling and root planing.

Release kinetics of ampicillin, characterization and bioactivity of TiO2/PCL hybrid materials synthesized by sol–gel processing

Poly(epsilon-caprolactone) (PCL 6, 12, and 24 wt %) and titanium (TiO2) organic-inorganic hybrid materials have been synthesized by the sol-gel method from a multicomponent solution containing titanium butoxide, poly(epsilon-caprolactone) (PCL), water, and chloroform (CHCl3). Sodium ampicillin was incorporated in the hybrid material to verify the effect as local controlled drug delivery system. The structure of a hybrid materials interpenetrating network is realized by hydrogen bonds between Ti-OH group (H-donator) in the sol-gel intermediate species and carboxylic group (H-acceptor) in the repeating units of the polymer. The presence of hydrogen bonds between organic/inorganic components of the hybrid materials was proved by FTIR analysis. The morphology of the hybrid materials was studied by scanning electron microscope (SEM). The structure of a molecular level dispersion has been disclosed by atomic force microscope (AFM), pore size distribution and surface measurements. The bioactivity of the synthesized hybrid materials has been showed by the formation of a layer of hydroxyapatite on the surface of TiO2/PCL samples soaked in a fluid simulating the composition of the human blood plasma. The amount of sodium ampicillin released has been detected by UV-vis spectroscopy and SEM. The release kinetics seems to occur in more than one stage. HPLC analysis has also been taken to ensure the integrity of ampicillin after the synthetic treatment.

Sol-gel processing of drug delivery materials and release kinetics

Silica, calcium (5 mol%) silicate and silica/polycaprolactone hybrid inorganic/organic amorphous materials, all mixed with sodium ampicillin, a broad-spectrum antibiotic, have been synthesized by sol-gel method. The amorphous nature of the gels was ascertained by X-ray diffraction analysis. Release kinetics in a simulate body fluid (SBF) have been subsequently investigated. The amount of sodium ampicillin released has been detected by UV-Vis spectroscopy and SEM. The release kinetics seems to occur in more than one stage. Finally FTIR measurements and SEM micrograph showed the formation of a hydroxyapatite layer on the surface of the samples soaked in SBF. All data showed that these materials could be used as drug delivery bioactive systems.