Longitudinal Clinical Evaluation of Adjunct Minocycline in the Treatment of Chronic Periodontitis

Effect of diode laser combined with minocycline hydrochloride in nonsurgical periodontal therapy: a randomized clinical trial

Background

This study aimed to assess the effect of diode laser combined with minocycline hydrochloride in conventional nonsurgical periodontal therapy.

Methods

Ninety-two patients and 1206 teeth were included in this study. The patients were diagnosed moderate or severe periodontal diseases with the presence of teeth in at least 3 quadrants in the oral cavity. Each patient’s quadrants were randomly divided into three treatment groups as following, Control group: scaling and root planning (SRP); Experimental group 1 (Exp 1): SRP + minocycline hydrochloride; Experimental group 2 (Exp 2): SRP + 809 nm diode laser + minocycline hydrochloride. The minocycline in Exp 1 and Exp 2 was applied once per week, for 4 weeks. Clinical examinations including periodontal probing depth (PD), clinical attachment level (CAL) and bleeding index (BI), and the secretion of inflammatory factor (tumor necrosis factor, TNF-α) was detected by ELISA before and 3, 6 months after the treatments. The differences among these groups were assessed by One-Way ANOVA and Kruskal–Wallis test. P-value < 0.05 was considered significant.

Results

All the periodontal indexes (PD, CAL and BI) were improved after each treatment and the secretion of TNF-α was reduced for all three groups. In patients with deep periodontal pockets, Exp 2 showed significant improvements in all indexes comparison with Con group and Exp group 1.

Conclusions

The synergistic effect of SRP and 809 nm diode laser combined with minocycline hydrochloride could play an efficient and reliable effect in the nonsurgical periodontal treatment approach.

Trial registration The clinical trial was retrospectively registered in chictr.org.cn with registration ChiCTR2100051708 (01/10/2021).

Bacterial resistance to minocycline after adjunctive minocycline microspheres during periodontal maintenance: A randomized clinical trial

BACKGROUND

Despite widespread use, the impact of minocycline hydrochloride microspheres on the shifts of oral bacterial species resistant to minocycline remains unknown. This study aimed at examining the percentage and taxonomy of minocycline-resistant isolates in saliva and subgingival plaque samples before and after minocycline microspheres application in periodontitis patients during maintenance.

METHODS

Patients received supra- and sub-gingival debridement with (test) or without (control) minocycline microspheres application to sites with probing depth >4 mm and were clinically monitored at baseline, 1, 3, and 6 months. Samples were collected at baseline, 1 and 6 months and analyzed via cultivation with or without 4 μg/mL minocycline. Percentage of resistant strains was determined by colony counting and taxonomy by checkerboard DNA-DNA hybridization. Significant clinical changes were sought with the Mann-Whitney test and differences in percentage of resistant isolates with the Friedman and Mann-Whitney tests.

RESULTS

Groups showed similar clinical improvements. Mean percentage of resistant isolates rose at 1 month and decreased at 6 months in saliva and plaque samples in test group (P <0.05) but remained unchanged in control group. Percentage of resistant isolates of Gemella morbillorum and Eubacterium saburreum increased significantly at 6 months in both groups. Antibiotic resistance by Aggregatibacter actinomycetemcomitans, Tannerella forsythia, and Porphyromonas gingivalis was either absent or infrequent.

CONCLUSION

Minocycline microspheres result in transient selection of minocycline resistant species in saliva and subgingival plaque samples.

Polymer-Based Carriers in Dental Local Healing-Review and Future Challenges

Polymers in drug formulation technology and the engineering of biomaterials for the treatment of oral diseases constitute a group of excipients that often possess additional properties in addition to their primary function, i.e., biological activity, sensitivity to stimuli, mucoadhesive properties, improved penetration of the active pharmaceutical ingredient (API) across biological barriers, and effects on wound healing or gingival and bone tissue regeneration. Through the use of multifunctional polymers, it has become possible to design carriers and materials tailored to the specific conditions and site of application, to deliver the active substance directly to the affected tissue, including intra-periodontal pocket delivery, and to release the active substance in a timed manner, allowing for the improvement of the form of application and further development of therapeutic strategies. The scope of this review is polymeric drug carriers and materials developed from selected multifunctional groups of natural, semi-synthetic, and synthetic polymers for topical therapeutic applications. Moreover, the characteristics of the topical application and the needs for the properties of carriers for topical administration of an active substance in the treatment of oral diseases are presented to more understand the difficulties associated with the design of optimal active substance carriers and materials for the treatment of lesions located in the oral cavity.

Adjunctive effect of locally delivered antimicrobials in periodontitis therapy: A systematic review and meta-analysis

AIM

To answer the following PICOS question: in adult patients with periodontitis, which is the efficacy of adjunctive locally delivered antimicrobials, in comparison with subgingival debridement alone or plus a placebo, in terms of probing pocket depth (PPD) reduction, in randomized clinical trials with at least 6 months of follow-up.

MATERIAL AND METHODS

A systematic search was conducted: 59 papers, reporting 50 different studies, were included. Data on clinical outcome variables changes were pooled and analysed using weighted mean differences (WMDs) and 95% confidence intervals (CI), and prediction intervals (PI), in case of significant heterogeneity.

RESULTS

Statistically significant differences were observed, in 6- to 9-month studies, for PPD (WMD = 0.365, 95% CI [0.262; 0.468], PI [-0.29; 1.01]) and clinical attachment level (CAL) (WMD = 0.263, 95% CI [0.123; 0.403], PI [-0.43; 0.96]). For long-term studies, significant differences were observed for PPD (WMD = 0.190, 95% CI [0.059; 0.321]), but not for CAL. For adverse events, no differences were observed. Results were affected by study design (split-mouth versus parallel studies) and assessment (full- or partial-mouth), as well as by the formulation tested.

CONCLUSIONS

The use adjunctive locally delivered antimicrobials in periodontitis therapy results in statistically significant benefits in clinical outcomes, without relevant side effects.

Antimicrobial photodynamic therapy versus antibiotics as an adjunct in the treatment of periodontitis and peri-implantitis: A systematic review and meta-analysis

BACKGROUND

Clinical efficacy of antimicrobial photodynamic therapy (aPDT) as compared to antibiotics in periodontitis and peri-implantitis has been tested in several clinical trials. Yet controversial results were reported. The aim of the present study was to answer the question: "Will adjunctive antimicrobial photodynamic therapy be more effective than antibiotics agent in the treatment of periodontitis and peri-implantitis?".

METHODS

Publications compared outcomes between aPDT and antibiotics in adult patients with periodontitis or peri-implantitis, containing more than 3-month follow-up duration, were involved in the systematic review and meta-analysis. PubMed, EMBASE and Cochrane Central were searched until December of 2020. Clinical parameters including pocket probing depth (PPD), clinical attachment level (CAL), and bleeding on probing (BOP) were evaluated. The risk of bias was assessed by Cochrane Collaboration Tool. Weighted mean differences (WMD), 95 % confidence interval(CI) and heterogeneity were estimated by Review Manager software.

RESULTS

10 trials in periodontitis and 5 trials in peri-implantitis were included. Meta-analysis outcomes revealed equal clinical evidence for aPDT and antibiotics in periodontitis and peri-implantitis. In addition, aPDT significantly reduced the red complex in both diseases. However, owing to the heterogeneity of protocols in articles and the limited number of studies, the comparative conclusion remained unconfirmed.

CONCLUSION

aPDT can be considered as an alternative to antibiotics in the treatment of peri-implantitis and periodontitis. Given that high heterogeneity in outcome was found in this review, future long-term clinical trials with standard aPDT and antibiotic treatment should be tested to arrive at a firm conclusion.

Evaluation of the efficacy of lycopene gel compared with minocycline hydrochloride microspheres as an adjunct to nonsurgical periodontal treatment: A randomised clinical trial

Background/purpose

The prescription of antibiotics as an adjunct to mechanical periodontal therapy in patients with severe periodontitis is recommended; however, the side effects of antibiotics are a major concern. The aim of this study was to evaluate the efficacy of lycopene (Lyc) antioxidant gel versus minocycline hydrochloride microspheres (ARISTIN) as an adjunct to the nonsurgical treatment of periodontitis.

Materials and methods

Three identical periodontal pockets/patient received root surface debridement followed by the random application of either ARISTIN, Lyc, or placebo gel (control, Ctrl). Clinical parameters, plaque index, bleeding on probing, probing pocket depth, and clinical attachment loss, were recorded at the baseline and after 30 days. Additionally, the levels of interleukin-8 (IL-8), matrix metallopeptidase 9, and tissue inhibitor of metalloproteinases 1 (TIMP1) in gingival crevicular fluid samples were assessed at the same time points.

Results

Twenty-three patients with periodontitis completed the study. Both ARISTIN and Lyc treatments showed significantly greater gains in attachment (1.94 ± 1.33 and 1.72 ± 0.88, respectively) than the Ctrl treatment (1.04 ± 0.96). Compared with those in the Ctrl, only ARISTIN showed a significant reduction in IL-8 level, whereas TIMP1 levels were significantly upregulated in the Lyc gel and ARISTIN sites. The effect size estimation indicated that Lyc gel exhibited considerably greater efficacy than the Ctrl gel.

Conclusion

Lyc gel and ARISTIN offer almost equal improvement in both clinical and biochemical parameters of periodontitis.

The risk reduction of recurrent periodontal pathogens of local application minocycline HCl 2% gel, used as an adjunct to scaling and root planing for chronic periodontitis treatment

Background

The aim of this study was to evaluate the clinical and microbiological effects of local application minocycline HCl 2% gel, used as an adjunct to scaling and root planing (SRP) for treatment of chronic periodontitis (CP). CP is an inflammation of periodontal tissue that is caused mainly by bacterial infection, where periodontal destruction such as loss of attachment and bone destruction occurred.

Methods

A total of 81 subjects with moderate to severe periodontitis whose baseline clinical attachment loss (CAL) was ≥4 mm were randomly assigned to receive SRP alone (control group, N=39) or SRP followed by four times of local application of minocycline HCl gel (Periocline) once a week (test group, N=42). Pocket depth, CAL, and papilla bleeding index were examined at baseline, 21 days, 2, 3, and 6 months. Subgingival plaque samples were collected with sterile curettes and were analyzed by real-time polymerase chain reaction for the presence of three periodontal pathogens (Porphyromonas gingivalis [P.g.], Tannerella forsythia [T.f.], and Treponema denticola [T.d.]) at baseline, 2, 3, and 6 months.

Results

The number of bacteria was reduced in both groups at 2 months after baseline (SRP treatment). The changes (2–6 months) in T.d. and T.f. counts in the test group were significantly lower than those in the control group. In the control group, a significant regrowth of P.g., T.f., and T.d. was observed from 2 to 6 months and of P.g. and T.f. from 3 to 6 months. On the other hand, in the test group, the number of the three bacteria did not significantly increase during the 6-month period.

Conclusion

The results showed that local application of minocycline, used as an adjunct to SRP, was effective for suppressing regrowth of periodontal pathogens, suggesting its risk reduction of recurrent periodontal pathogens in CP.

Minocycline Ointment as a Local Drug Delivery in the Treatment of Generalized Chronic Periodontitis - A Clinical Study

INTRODUCTION

The primary goal in periodontal therapy includes removal of the etiological factors by mechanical periodontal treatment, which sometimes fail to eliminate the anaerobic infection at the base of the pocket and requires adjuvant chemical therapy.

AIM

The aim of the study was to evaluate the effectiveness of 2% minocycline ointment when used as an adjunct to periodontal flap surgery and post-operative maintenance period for the treatment of generalized chronic periodontitis.

MATERIALS AND METHODS

The study included 30 subjects comprising of 60 posterior sextants in a split mouth design in which 30 sextants were treated as experimental and 30 sextants as control with a probing pocket depth≥6mm. In Group A (experimental group) 30 sextants were treated with open flap debridement followed by the application of minocycline ointment as a local drug delivery. In Group B (control group) 30 sextants were treated with open flap debridement alone. Minocycline hydrochloride ointment was applied on the 0 day and 3(rd) month. The clinical parameters such as plaque index, probing pocket depth, clinical attachment level and gingival bleeding index were recorded at 0 day, 3(rd) month and 6(th) month in both the groups. Paired and unpaired t-test were used to compare the means of the two groups.

RESULTS

When Group A and Group B were compared, Group A showed significantly greater reduction in gingival bleeding index, probing pocket depth and gain in clinical attachment level than Group B, from 0 day to 3 months and from 0 day to 6 months. Group A showed significant reduction in plaque index than Group B when they were compared at 6 months.

CONCLUSION

The results demonstrate that there was significant reduction in the clinical parameters with improvement in the periodontal status on application of minocycline ointment as an adjunct to periodontal flap surgery in generalized chronic periodontitis.

Tetracycline as local drug delivery in treatment of chronic periodontitis: A systematic review and meta-analysis

Background:

The aim of the present meta-analysis is to determine the efficacy of tetracycline group of antibiotics as local drug delivery agents in the treatment of chronic periodontitis.

Materials and Methods:

MEDLINE, EBSCO, Cochrane database, and Google Scholar were used to identify studies in English published up to January 31, 2017. An additional hand search of relevant journals and of the bibliographies of the paper identified was also performed. Articles retrieved were screened using specific inclusion criteria by two independent reviewers. Randomized control trials investigating the effect of tetracycline group of antibiotics as local drug delivery agents in chronic periodontitis were included in the study.

Results:

Ten relevant articles were selected for the meta-analysis, of which five articles were retrieved after electronic search, three articles were included after hand search, and two unpublished articles were included. The number of patients in studies ranged from 13 to 140 sites with mean age ranging from 20 to 75. A total of 588 sites were treated using tetracycline group of antibiotics as local drug delivery agents in the treatment of chronic periodontitis. The meta-analysis showed standard difference in mean −1.02 mm (95% confidence interval [CI] 0.28, 1.75) for clinical gain in attachment in favor of tetracycline group. Standard difference in mean for probing depth (PD) was 1.20 mm (95% CI 0.57, 1.87) in tetracycline group.

Conclusion:

The results of this meta-analysis showed a significant improvement in periodontal parameters such as CAL, PD, and sulcular bleeding index in favor of tetracycline as local drug delivery compared to placebo.

Scaling and root planning, and locally delivered minocycline reduces the load of Prevotella intermedia in an interdependent pattern, correlating with symptomatic improvements of chronic periodontitis: a short-term randomized clinical trial

Background

To evaluate the respective or combinatory efficacy of locally delivered 2% minocycline (MO), and scaling and root planning (SRP) by assessing both clinical parameters and the loads of four main periodontal pathogens in treating chronic periodontitis (CP).

Methods

Seventy adults with CP were randomly assigned to the three treatment groups: 1) SRP alone; 2) MO alone; and 3) combinatory use of SRP and MO (SRP + MO). Before and 7 days after the treatments, we evaluated both clinical parameters (pocket depth [PD] and sulcus bleeding index [SBI]) and the gene load of four main periodontal pathogens (Aggregatibacter actinomycetemcomitans [Aa], Fusobacterium nucleatum [Fn], Porphyromonas gingivalis [Pg], and Prevotella intermedia [Pi]).

Results

The bacterial prevalence per patient was: Aa, 31.25%; Fn, 100%; Pg, 95.31%; and Pi, 98.44%. Seven days after treatment, the three treatments significantly reduced both PD and SBI, but not detection frequencies of the four pathogens. For PD, the reduction efficacy of SRP + MO was significantly higher than that of either MO or SRP. Only Pg responded significantly to SRP. Pg and Fn were significantly reduced in the presence of MO. Only SRP + MO showed a significant reduction effect on the gene load of Pi. The reduction of PD significantly correlated with the gene load of Pi (r=0.26; P=0.042) but not of the other bacteria.

Conclusion

SRP and MO reduced the load of Pi in an interdependent pattern, which correlated with symptomatic improvements of CP.

Comparison of Periochip (chlorhexidine gluconate 2.5 mg) and Arestin (Minocycline hydrochloride 1 mg) in the management of chronic periodontitis

BACKGROUND

The aim of the study was to compare the efficacy of chlorhexidine gluconate 2.5 mg (Periochip) and Minocycline hydrochloride 1 mg (Arestin) as local drug delivery agents in the management of chronic periodontitis.

MATERIALS AND METHODS

Twenty patients in the age group of 30-50 years suffering from chronic periodontitis (12 males and 8 females), with almost identical probing depth bilaterally (5-8 mm), and exhibiting bleeding on probing were selected and divided into two groups: Group I consisted of periodontal pockets on the left side and received Periochip and group II consisted of periodontal pockets on the right side and received Arestin. Patients were recalled after 6 weeks and 3 months intervals from the baseline visit to record plaque index, gingival index, and probing depth.

RESULTS

There was reduction in all the parameters in both the groups at 6 weeks and 3 months as compared to baseline.

CONCLUSION

From the results of the present study, it was concluded that both the drugs were equally effective in reduction of plaque scores as well as gingival scores. It was further observed that Arestin resulted in better results at 6 weeks while Periochip showed better results at 3 months with respect to probing depth reduction.

Comparative evaluation of locally delivered minocycline and metronidazole in the treatment of periodontitis

Objective:

The aim of this study was to evaluate and compare the efficacy of subgingivally delivered Minocycline microspheres and 25% Metronidazole gel when used as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis.

Materials and Methods:

A randomized, controlled, single center study was conducted involving 60 sites in 20 patients suffering from moderate to advanced chronic periodontitis. Each patient contributed three sites which were randomized to three treatment groups: SRP + insertion of Minocycline microspheres at day 1 (Group A), SRP + insertion of Metronidazole gel at day 1 and at day 7 (Group B), and SRP alone (Group C). Gingival index (GI), plaque index (PI), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded at day 1, 1 month, and 3 months post therapy.

Results:

All treatments showed significant reductions in PPD and CAL at 1 and 3 months when compared to baseline values (P < 0.001). At 3 months, sites treated with minocycline showed an additional reduction in PPD of 0.85 ± 0.03 mm, significantly greater than SRP alone. Differences in mean PPD reduction between Group B and Group C and between Group A and Group B were not significant. At 3 months, difference in CAL gain between Group A and C was 0.50 ± 0.45, which was statistically significant and between Group B and C was 0.35 ± 0.11, which was not found to be statistically significant (P = 0.20). Differences in relative CAL between Group A and Group B were also not found to be statistically significant (P = 0.53).

Conclusion:

The results concluded that treatment with Minocycline microspheres and Metronidazole gel improve PPD and CAL in patients with periodontitis compared to SRP alone.

Minocycline hydrochloride nanoliposomes inhibit the production of TNF-α in LPS-stimulated macrophages

Background

As an adjunctive treatment of chronic periodontitis, it seems that the application of periocline or the other antimicrobials is effective against periodontopathogens. In this study, nanoliposomes were investigated as carriers of minocycline hydrochloride and the inhibition effects of minocycline hydrochloride nanoliposomes on the proliferation and lipopolysaccharide (LPS)-stimulated production of tumor necrosis factor-α (TNF-α) of macrophages were elucidated.

Methods

After stimulation with 10 μg/mL LPS, murine macrophages (ANA-1) were treated with 10, 20, 40, 50 and 70 μg/mL 2% minocycline hydrochloride nanoliposomes, minocycline hydrochloride solution, and periocline for 6, 12, 24, 48 and 60 hours, respectively. A tetrazolium (MTT) assay was used to evaluate macrophages cell proliferation rate and the levels of TNF-α mRNA were measured by SYBR Green Real Time PCR.

Results

Ten to 70 μg/mL 2% minocycline hydrochloride nanoliposomes, minocycline hydrochloride solution, and periocline showed dose- and time-dependent inhibition of ANA-1 proliferation. Minocycline hydrochloride nanoliposomes showed dose- and ratio-dependent inhibition of LPS-stimulated TNF-α secretion of ANA-1. The inhibition effect of 10 μg/mL minocycline hydrochloride nanoliposomes was significantly better than that of two positive control groups, and equated to that of 60 or 70 μg/mL periocline. The expression of TNF-α mRNA in experimental group continued to reduce linearly with time.

Conclusion

All three preparations of minocycline hydrochloride showed dose- and time-dependent inhibition of proliferation of ANA-1. Minocycline hydrochloride nanoliposomes have stronger and longer inhibition effect on LPS-stimulated TNF-α secretion of macrophages cell than minocycline hydrochloride solution and periocline.

Single use of tetracycline with and without diclofenac sodium as local drug delivery in pocket therapy: a clinico-microbiological study

AIM

  Local drug delivery is a non-surgical method in the treatment of periodontitis. Different chemotherapeutic agents are used for local drug delivery; one such agent is tetracycline, a broad-spectrum antibiotic. Recent studies have also shown that the use of non-steroidal anti-inflammatory drugs reduces pro-inflammatory cytokines and acts as host modulator. Thus, an attempt was made to compare and evaluate the efficacy of tetracycline alone and in combination with diclofenac sodium as a local drug delivery.

METHODS

  A total of 36 sites with chronic periodontitis were divided into three groups with 12 sites each (i.e. group A, antibiotics alone; group B, antibiotics in combination with non-steroidal anti-inflammatory drugs; and group C, control group). For all the groups, the following parameters (plaque index, papillary bleeding index, probing pocket depth, and microbial analysis) were assessed and statistically analyzed.

RESULTS

  The antibiotic and non-steroidal anti-inflammatory drug combination group showed a statistically-significant improvement in clinical parameters and a shift in microbial flora when compared to the group with antibiotics alone. However, the control group failed to show any statistically-significant improvement.

CONCLUSION

  Antibiotics in combination with non-steroidal anti-inflammatory drugs are more efficient than using antibiotics alone as local drug delivery for the treatment of periodontal pockets.

The Application of Microencapsulation Techniques in the Treatment of Endodontic and Periodontal Diseases

In the treatment of intracanal and periodontal infections, the local application of antibiotics and other therapeutic agents in the root canal or in periodontal pockets may be a promising approach to achieve sustained drug release, high antimicrobial activity and low systemic side effects. Microparticles made from biodegradable polymers have been reported to be an effective means of delivering antibacterial drugs in endodontic and periodontal therapy. The aim of this review article is to assess recent therapeutic strategies in which biocompatible microparticles are used for effective management of periodontal and endodontic diseases. In vitro and in vivo studies that have investigated the biocompatibility or efficacy of certain microparticle formulations and devices are presented. Future directions in the application of microencapsulation techniques in endodontic and periodontal therapies are discussed.

Effect of antimicrobial periodontal treatment and maintenance on serum adiponectin in type 2 diabetes mellitus

AIMS

The aims of this study were to evaluate the effect of mechanical periodontal treatment with local application of minocycline (APT) on serum adiponectin as a marker of insulin resistance improvement in type 2 diabetes mellitus (T2DM) patients and to investigate if effect of APT on serum adiponectin level was sustained by periodontal maintenance (PM).

MATERIAL AND METHODS

Twenty-seven T2DM patients were randomly assigned into test or control groups. Test received scaling with ultrasonic devices at baseline and APT biweekly for 2 months while control received scaling at baseline and mechanical tooth cleaning (MPT) at the same interval. At 6 months, all patients received mechanical tooth cleaning as PM. Periodontal examination and blood measurements were performed at baseline, 4 and 9 months.

RESULTS

Adiponectin concentrations in test had significantly increased by 31.4% after APT (p=0.024) and by 30.4% after PM (p=0.002) compared with baseline. The percentage of >or=4 mm probing depths (PD) had shown 8.3% and 9.3% reduction after APT and PM (p=0.046, 0.02) in test while 5.0% reduction after MPT in control group (p=0.031).

CONCLUSIONS

Our results suggested that APT and PM not only improve periodontal disease but also increase serum adiponectin in T2DM patients.

Topical use of a metronidazole gel in the treatment of sites with symptoms of recurring chronic inflammation

BACKGROUND

Bacterial plaque accumulation at the dentogingival junction and in periodontal pockets is the major etiologic factor in all manifestations of periodontal disease. The aim of this study was to evaluate whether a locally delivered 25% metronidazole gel after scaling and root planing (SRP) would enhance the treatment outcome over SRP alone in periodontal pockets with symptoms of recurring chronic inflammation.

METHODS

Twenty-one maintenance-care patients, 10 men and 11 women, having at least one pair of contralateral anatomically matching proximal tooth surfaces showing probing depth > or = 5 mm and bleeding on probing (BOP), were included in the study. The sites were randomized to be treated with SRP plus 25% metronidazole gel (test sites) or with SRP alone (control sites) in a split-mouth design. Clinical evaluations were performed immediately pretreatment (baseline) and at 3 and 6 months post-treatment.

RESULTS

Both treatments yielded a statistically significant (P = 0.001) reduction in probing depth (1.9 and 1.8 mm), gain of attachment level (1.6 and 1.0 mm), and reduction of BOP (38.1% and 33.3%) for test and control sites, respectively, at 6 months. There was no statistically significant difference between the treatments for any of the clinical parameters.

CONCLUSION

This study indicates that a locally applied 25% metronidazole gel does not improve the treatment outcome over SRP alone in sites with recurring chronic inflammation in maintenance-care patients.

Minocycline HCl Microspheres Reduce Red-Complex Bacteria in Periodontal Disease Therapy

BACKGROUND

The objective of this trial was to measure the antimicrobial effects of a minocycline HCl microsphere (MM) local drug-delivery system when used as an adjunct to scaling and root planing (SRP). DNA probe analysis for 40 bacteria was used to evaluate the oral bacteria of 127 subjects with moderate to advanced chronic periodontitis.

METHODS

Subjects were randomly assigned to either SRP alone (N = 65) or MM + SRP (N = 62). The primary endpoints of this study were changes in numbers and proportions of the red-complex bacteria (RCB) and the sum of Porphyromonas gingivalis, Tannerella forsythia (formally T. forsythensis), and Treponema denticola relative to 40 oral bacteria at each test site from baseline to day 30. Numbers of RCB from the five test sites were averaged to provide a value for each subject.

RESULTS

MM + SRP reduced the proportion of RCB by 6.49% and the numbers by 9.4 x 10(5). The reduction in RCB proportions and numbers by SRP alone (5.03% and 5.1 x 10(5), respectively) was significantly less. In addition, MM + SRP reduced probing depth by 1.38 mm (compared to 1.01 mm by SRP alone), bleeding on probing was reduced by 25.2% (compared to 13.8% by SRP alone), and a clinical attachment level gain of 1.16 mm (compared to 0.80 mm by SRP alone) was achieved.

CONCLUSION

These observations support the hypothesis that RCBs are responsible for periodontal disease and that local antimicrobial therapy using MM + SRP effectively reduces numbers of RCBs and their proportions to a greater extent than SRP alone.