The effect of 1% metronidazole gel in routine maintenance of persistent furcation involvement in human beings

Povidone-Iodine Used as an Adjunct to Non-Surgical Treatment of Furcation Involvements

BACKGROUND

The aim of this clinical trial was to evaluate the effect of topically applied povidone-iodine (polyvinylpyrrolidone and iodine [PVP-I]) used as an adjunct to non-surgical therapy of furcation involvements.

METHODS

Forty-four patients presenting at least one Class II furcation involvement that bled on probing with probing depth (PD)>or=5 mm were recruited. Patients were stratified into two treatment groups: 1) subgingival instrumentation by an ultrasonic device using PVP-I (10%) as the cooling liquid (test); and 2) identical treatment using distilled water as the cooling liquid (control). The following clinical outcomes were evaluated: plaque index, bleeding on probing (BOP), position of the gingival margin, relative attachment level (RAL), PD, and relative horizontal attachment level (RHAL). The N-benzoyl-L-arginine-p-nitroanilide (BAPNA) test was used to analyze the trypsin-like activity in dental biofilm. The clinical and biochemical parameters were evaluated at baseline and 1, 3, and 6 months after therapy.

RESULTS

Both groups had similar means of PD reduction and RAL and RHAL gain. At 6 months, these variables were, respectively, 2.31, 1.17, and 1.00 mm in the control group and 2.31, 1.23, and 1.02 mm in the test group. There was also no difference between groups regarding the number of furcation sites presenting RAL gain>or=2 mm. The results of the BAPNA test failed to demonstrate significant differences between groups.

CONCLUSION

Non-surgical therapy can effectively treat Class II furcation involvements, and the use of topically applied PVP-I as an adjunct to subgingival instrumentation does not provide additional benefits.

Periodontal therapy using local delivery of antimicrobial agents

Antimicrobial agents, systemic and/or local, are thought by some to be effective agents for treating periodontal infections. Here the authors determine the costs and benefits of local delivery agents for treating periodontal disease. Applying this cost-benefit analysis to patient care, however, will depend upon a clinician's expertise and a patient's value system.

Clinical and antimicrobial effects of a single episode of subgingival irrigation with tetracycline HCl or chlorhexidine in deep periodontal pockets

15 adults, each providing 4 non-adjacent untreated periodontal pockets with a probing depth (PD) exceeding 6 mm, volunteered for a randomized, split-mouth, double-blind, clinical study evaluating subgingival irrigation with chlorhexidine (CHX) or tetracycline HCl (TTC). The study protocol included oral hygiene instructions followed by scaling and root planing. Experimental and immediately adjacent teeth did not receive instrumentation. The 4 deep periodontal pockets in each patient were assigned to be irrigated with 150 ml CHX (0.12%), TTC (10 or 50 mg/ml; TTC10, TTC50), or sterile saline (control) in a single episode. Post-irrigation mechanical plaque control was supported by 2x daily CHX rinses throughout the 12-week observation interval. Recordings of oral hygiene (P1I), gingival health (GI), bleeding on probing (BoP), probing depth (PD), clinical attachment level (CAL), and microbial morphotypes from subgingival paper point samples were performed pre-irrigation, and at 1, 2, 4, 6, 8, 10, and 12 weeks post-irrigation. Mean post-irrigation P1I was low, fluctuating between 0.0 and 0.4, without significant differences between experimental groups. Mean pre-irrigation GI approximated 1.4 and reached 0.8 at the exit of study without significant differences between experimental groups. All experimental sites exhibited BoP pre-irrigation. BoP was significantly reduced in TTC50 compared to TTC10, CHX and control sites from week 8 post-irrigation. PDs were reduced for the experimental groups with TTC50 exhibiting the strongest reduction. CALs remained unaltered from pre-irrigation for TTC10, CHX and control sites over the 12-week observation interval, whereas TTC50 sites consistently improved to significantly differ from all other groups at week 10 and 12 post-irrigation. The distribution of bacterial morphotypes was significantly altered towards one of periodontal health for all experimental groups with a profound effect for TTC50 sites. Our results suggest that subgingival irrigation with TTC solutions at high concentrations may have a role in the management of adult periodontitis.

A controlled multicenter study of adjunctive use of tetracycline periodontal fibers in mandibular class II furcations with persistent bleeding

The aim of this randomized single-blind multicenter controlled clinical trial was to clinically evaluate the effectiveness of adjunctive local controlled drug delivery in the control of bleeding on probing in mandibular class II furcations during maintenance care. 127 patients presenting with a class II mandibular furcation with bleeding on probing were included in the study. They had been previously treated for periodontitis and were participating in supportive care programs in periodontal specialty practices. Treatments consisted of scaling and root planing with oral hygiene instructions (control) and scaling and root planing and oral hygiene combined with local controlled drug delivery with tetracycline fibers (test). The following outcomes were evaluated at baseline and 3 and 6 months after therapy at the furcation site: bleeding on controlled force probing (BOP), probing pocket depth (PD) and clinical attachment levels (CAL). Levels of oral hygiene and smoking status were also assessed. Both test and controls resulted in significant improvements of BOP and PD at 3 and 6 months. The test treatment, however, resulted in significantly better improvements: BOP decreased by 52% in the control group and by 70% in the test group at 3 months; at 6 months, however, the difference was no longer significant. The test treatment resulted in a 0.5 mm greater reduction of PD than the control at 3 months, the improvement was highly significant but its duration did not extend until the 6 months evaluation. No differences were observed in terms of changes in CAL. These data indicate that addition of tetracycline fibers to mechanical therapy alone resulted in improved control of periodontal parameters during periodontal maintenance of class II mandibular furcations. Short duration of the effect, however, requires further investigations to optimize conservative treatment of these challenging defects.

Microbiological response to mechanical treatment in combination with adjunctive therapy. A review of the literature

The recognition of the microbial origin and the specificity of periodontal infections has resulted in the development of several adjunctive therapies (antibiotics and/or antiseptics) to scaling and root planing in the treatment of chronic adult periodontitis. This article aims to review the "additional" effect of a subgingival irrigation with chlorhexidine, or a local or systemic application of tetracycline or metronidazole, performed in combination with a single course of scaling and root planing in patients with chronic adult periodontitis. All treatment modalities are compared with scaling and root planing, based on their impact on: the probing depth (PD); total number of colony forming units per ml (CFU/ml); the proportions and/or the detection-frequency of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia; and/or on the percentages of cocci, spirochetes, motile, and other micro-organisms on dark field microscopy examination. All treatment modalities, including scaling and root planing without additional chemical therapy, resulted in significant reductions in the probing depth and the proportions of periodontopathogens, at least during the first 8 weeks post-therapy. However in comparison to a single course of scaling and root planing, the supplementary effect of adjunctive therapies seems to be limited. In general, only the irrigation with chlorhexidine 2%, the local application of minocycline, and the systemic use of metronidazole (in case of large proportions of spirochetes) or doxycycline (in case of large proportions of A. actinomycetemcomitans) seem to result in a prolonged supplementary effect when compared to scaling and root planing. Therefore, the use of antibiotics on a routine basis, especially in a systemic way, in the treatment of chronic adult periodontitis, can no longer be advocated, considering the increasing danger for the development of microbial resistance.

Concentration of metronidazole in periodontal pockets after application of a metronidazole 25% dental gel

The metronidazole concentration was monitored in gingival crevicular fluid (GCF) of inflamed periodontal pockets after 1 application of a 25% gel. 12 patients with periodontal disease were included in the study. Metronidazole gel was applied with a syringe into the pockets of 10 teeth with probing depths > or = 5 mm. Samples of GCF were taken with Periopaper before application and 4, 8, 12, 24 and 36 h after application. At each time, samples from 2 teeth were pooled in order to obtain a sufficient amount of fluid for analysis. By means of a calibrated Periotron, the collected volume of GCF was measured. High-performance liquid chromatography was used to determine the amount of metronidazole. MIC50 for anaerobic periopathogens susceptible to metronidazole is below 1 microgram/ml. In this study, the concentration obtained was higher than 1 microgram/ml in all samples after 4 and 8 h, in 92% after 12 h, in 50% after 24 h and in 8% after 36 h. Thus, metronidazole concentrations in the pockets were generally above MIC50 for susceptible periopathogens 24 h after 1 application of a 25% metronidazole gel.

Systemic absorption of metronidazole after application of a metronidazole 25% dental gel

Systemic absorption of metronidazole was studied after one application of a metronidazole 25% dental gel into inflamed periodontal pockets. 14 patients with periodontal disease participated. Metronidazole gel was applied into the pockets of all teeth with probing depth > or = 5 mm, minimum 10 teeth/patient. Excess gel was carefully collected in order to calculate the amount of metronidazole applied into the pockets. Blood samples for analysis of metronidazole in plasma were taken before and up to 72 h after application. To determine the bioavailability of metronidazole administered as gel, the patients were later given an i.v. dose of 100 mg metronidazole. Metronidazole was quantified by HPLC. The mean actual dose of metronidazole in gel was 55 mg (SD: 24 mg, range: 29-103 mg). Allowing for the fact that excess gel corresponding to about 60% of the applied amount of metronidazole under normal clinical conditions may be swallowed, the systemic load after one application of metronidazole 25% dental gel will still be less than after one metronidazole 250 mg tablet. Peak plasma concentrations varied between 223 and 1303 ng/ml (mean: 581 ng/mk, SD: 320 ng/ml) and were reached within 2 to 8 h (mean: 4.4 h). The mean bioavailability of metronidazole dental gel was 71%.