The effect of short-term administration of minocycline HCl on gingival inflammation and subgingival microflora

Chemotherapeutic agents and periodontal therapy. Their impact on clinical practice

This paper reviews developments in chemotherapeutic agents relative to their impact on clinical practice. These agents are discussed in terms of their effect on plaque, gingivitis, periodontitis, hypersensitive dentin and re-attachment procedures. The paper also provides a perspective on delivery systems.

Repair of an extensive periodontal defect after tetracycline administration. A case report

A pathologically migrated maxillary central incisor tooth with a poor periodontal prognosis was treated successfully with conventional periodontal therapy. After almost 4 years, an extensive periodontal lesion developed on the same tooth and extraction was recommended. The patient did not comply and the acute symptoms disappeared after the administration of 1 gm of Tetracycline a day for 2 weeks. Although no definitive periodontal therapy was done, complete resolution of the lesion occurred with the healing of the structures of the periodontium and a dramatic reduction in mobility of the tooth. Antibacterial therapy could be an effective means of treating some periodontal lesions once a more exact and direct association is established between the various clinical forms of periodontitis and specific periodontal or groups of pathogens.

A 7-month study of sulcular fluid flow in the assessment of healing after debridement of deep pockets

The purpose of this investigation was to assess the value of sulcular fluid flow (SFF) measurements in evaluation of the healing of deep periodontal pockets after scaling and root planing. Fourteen adult patients with advanced periodontal disease received supragingival prophylaxis and instructions in oral hygiene. Immediately after baseline examination, meticulous scaling and root planing were performed. One to five selected pockets per patient were monitored on Days 0, 30, 120 and 210. Subgingival microbial proportions, sulcular fluid flow, probing depth, Gingival Index and bleeding after probing were assessed and recorded. The subgingival microbial proportions were determined with darkfield microscopy. The periodontal conditions were markedly improved by Day 210 as depicted by the microbial proportions. The proportion of motile micro-organisms was reduced from 51% at baseline to 9% on Day 30. This result was sustained until Day 210. Healing was also evident from the changes in Gingival Index scores and bleeding after probing. Probing depth was reduced from a mean of 8.3 to 4.5 mm. Correlations between the individual means recorded for the clinical parameters and bacterial proportions were calculated for the pooled data of all four examinations. Sulcular fluid flow did not correlate with the clinical parameters. Gingival Index, bleeding after probing or probing depth. The latter three parameters correlated significantly with the microbial proportions and each other. When the pooled tooth surface recordings of Days 30, 120 and 210 were divided into two groups according to the proportion of motile bacteria (the groups with less than 18% of spirochetes and motile rods and the groups with greater than 18% of spirochetes and motile rods), a significant difference in the mean amount of sulcular fluid flow (P less than 0.01) and mean probing depth (P less than 0.001) could be demonstrated between the two groups.

Adsorption of antibiotic TA to dental hard tissues

Antibiotic TA (TA) is a wide-spectrum, bactericidal antibiotic produced by Myxococcus xanthus strain TA. It was previously demonstrated that TA binds tightly to soft tissues while retaining its bactericidal activity in the bound form. The present study was undertaken to investigate TA adsorption to dental hard tissues. Slabs of dental tissues that had been cut from periodontally-involved extracted human teeth were treated with TA and then washed in saline with shaking (saline being replaced every 15 minutes). After 30, 60, and 120 minutes of washing, 45, 39, and 27% of the input TA activities were retained on the slabs, respectively. The tooth-bound TA was released slowly into the aqueous medium in active form. Similar experiments with beta-lactam antibiotics resulted in no significant adhesion to the slabs. The study demonstrates that TA binds tightly to dental tissues while retaining its bactericidal properties.

Antibiotic susceptibilities of periodontal bacteria. In vitro susceptibilities to eight antimicrobial agents

In vitro susceptibilities of 369 to 966 bacterial isolates from periodontal lesions to eight antibiotics were determined by agar dilution technique as a means of determining which antimicrobial agents were inhibitory for bacteria frequently associated with destructive periodontal diseases. Although most bacteria were relatively susceptible to the penicillins, greater activity was generally noted with amoxicillin than with either penicillin or ampicillin with the exception of Selenomonas sputigena and Peptostreptococcus. Antibacterial activities obtained with minocycline were significantly higher than with tetracycline for Actinobacillus actinomycetemcomitans and Streptococcus but comparable for most other taxa. Clindamycin and metronidazole both demonstrated excellent activity against the anaerobic Gram-negative rods but were less effective against some of the capnophilic and facultative organisms. Eikenella corrodens was exceptionally resistant to both of these drugs; and A. actinomycetemcomitans was generally resistant to clindamycin but relatively susceptible to metronidazole. Erythromycin was considerably less active than the other antibiotics against the majority of the periodontal bacteria. No single antibiotic, at concentrations equivalent to those achieved in body fluids, was uniformly effective in inhibiting all bacteria currently implicated or suspected as etiologic agents of periodontal diseases.

Effects of short-term administration of metronidazole on the subgingival microflora

The effect of a 5-day course of systemic metronidazole was investigated in 11 recall maintenance patients over a period of 3 months. Crevicular fluid flow, bleeding on probing, pocket depth, and composition of the subgingival microbiota as observed by dark-field microscopy, were measured. The study design allowed patients to act as their own controls. At baseline 1 (day 0), each patient had a randomly assigned quadrant scaled and root-planed, and received oral hygiene instruction. Microbiological and clinical parameters were measured at baseline 1 (before treatment) and at 3, 6, and 12 weeks in both the root-planed and a designated no-treatment quadrant. At baseline 2 (12 weeks), the contralateral quadrant was scaled and root-planed, and the oral hygiene instruction was reinforced. At this appointment, each patient was given 15 metronidazole tablets (250 mg), 1 to be taken 3 times per day for 5 days. At the end of this period, patients were seen 1-2 h after taking their last tablet, and blood and crevicular fluid samples were taken to determine the concentration of metronidazole by microbiological assay in the serum and crevicular fluid. Microbiological and clinical parameters were measured at baseline 2 (before treatment) and at 13, 15, 18, and 24 weeks in both the root-planed and designated non-root-planed (metronidazole only) quadrants. Results demonstrated that in this group of recall maintenance patients, metronidazole was no more effective than root-planing alone in reducing the relative % of total motile organisms and spirochetes in 5-8 mm pockets. Crevicular fluid flow was, however, significantly reduced for 11 weeks; serum and crevicular fluid levels of metronidazole were similar 1 to 2 h after drug ingestion.

Tetracyclines inhibit tissue collagenases. Effects of ingested low-dose and local delivery systems

In a series of experiments, Golub et al. demonstrated that tetracyclines, but not other antibiotics, can inhibit mammalian collagenases and proposed that this property could be useful in treating diseases, such as periodontal disease (but also included certain medical conditions, e.g., corneal ulcers) characterized by excessive collagen degradation (J Periodont Res 1983, 1984 and 1985; Experientia 1984; Cornea 1984). One effect was the dramatic reduction of tissue collagenase activity within the gingival crevicular fluid (GCF) of periodontal pockets after administering a standard regimen of a tetracycline (e.g., 200 mg minocycline or 1000 mg tetracycline/day). The preliminary studies described below determined the effect of (1) low-dose (LD; 40-80 mg/day) orally administered minocycline on GCF collagenase activity and on the subgingival microflora (Exp. I), and (2) tetracycline-loaded monolithic fibers (TF) on collagenase activity in vitro (Exp. II). In Exp. I, GCF collagenase activity was reduced by 45 to 80% 2 weeks after initiating LD minocycline therapy, an effect that lasted for at least several weeks after stopping drug treatment. No consistent change in the relative proportions of G(+), G(-) and motile subgingival microorganisms was detected as a result of LD treatment suggesting that the reduction in GCF collagenase activity was a direct inhibition of the enzyme by the drug. In Exp. II, 3- and 6-mm lengths of TF in vitro established tetracycline concentrations in 250 microliters of 132 micrograms/ml, from 3-mm lengths, and 265 micrograms/ml, from 6-mm lengths, after an 18-hour incubation.(ABSTRACT TRUNCATED AT 250 WORDS)

Antimicrobial irrigation of deep pockets to supplement non-surgical periodontal therapy. II. Daily irrigation

106 sites with probing pocket depths 7 mm or greater from 14 patients were treated with plaque control instruction and 1 episode of root planing. Sites in each patient were either irrigated with 2% chlorhexidine or left as non-irrigated controls. Irrigation immediately followed root planing and was repeated daily, by the patient, for 24 weeks. Clinical measurements were made at 12 and 24 weeks, as were gingival washings for determining the number and % of spirochetes. Results at 24 weeks demonstrated that bleeding scores decreased from 91% to 9%; the % of spirochetes dropped from approximately 9% to less than 1%; probing pocket depths decreased from 7.5 to 4.5 mm, and probing attachment levels gained 1.1 to 1.4 mm. The chlorhexidine irrigated experimental group and the non-irrigated control group did not differ significantly in any of the studied parameters. Thus, daily patient-administered chlorhexidine irrigation of deep pockets did not augment the effects of non-surgical periodontal therapy.

Antimicrobial irrigation of deep pockets to supplement oral hygiene instruction and root debridement. I. Bi-weekly irrigation

64 sites with probing pocket depth greater than or equal to 6 mm from 11 patients were treated with plaque control instruction and one episode of root planning. Subsequently, selected sites in each patient were irrigated with either chlorhexidine, tetracycline, saline or served as non-irrigated control sites. Irrigation immediately followed instrumentation, and was repeated every 2 weeks for 24 weeks. Healing was monitored at 8, 16, and 24 weeks clinically and at 7, 15, and 23 weeks with subgingival washings for determination of % as well as total number of spirochetes. The following changes were apparent from comparing pooled site means at 24 weeks with pretreatment data: (1) bleeding sites decreased from 62 of 64 sites initially to 22 of 64 at 24 weeks; (2) spirochetes decreased from 34% to 2%; (3) probing pocket depths decreased from 7.6 to 4.7 mm; (4) probing attachment levels showed a gain of 1.2 mm. The improvement of the chlorhexidine and tetracycline irrigated sites was similar to that of the saline irrigated and non-irrigated control sites. Thus, biweekly chlorhexidine, tetracycline or saline irrigation of deep pockets did not appear to augment the effects of non-surgical periodontal therapy.

The application of a collagen stabilizer to the gingiva of the beagle dog. Effect on ligature-induced periodontal disease

The objective of this study was to determine the effect of crevicular application of a collagen stabilizer on ligature-induced periodontal disease in beagle dogs. Fourteen male and female dogs, 15 months of age, were studied. The mandibular first molars and third and fourth premolars were ligated for 6 months and moderate periodontitis resulted. Ligatures were removed for 2 months and then replaced for an additional 3 months to experimentally mimic the episodic changes seen in human periodontal disease. Following this phase, ligatures were removed and the animals were assigned to a placebo or treatment group. Medications were then applied intracrevicularly, three times a week over 5 months using an IMAX irrigator. Clinical indices measured were plaque index (PI), gingival index (GI), gingival crevicular fluid flow (GCF), attachment level (AL), pocket depth (PD) and standardized radiographic analysis of alveolar bone height. While overall changes in PI, GI and GCF were not significant, the results showed that alveolar bone regeneration was increased approximately twice as much in the treatment group as compared to the placebo group, PD improved by 20% vs. 12.5% (P less than 0.001) and AL improved by 8.8% vs. 4.5% (P less than 0.001). The data were also evaluated in terms of the response in more severe sites as compared to those less severe. The results of these evaluations showed the more severe sites to be significantly more responsive to treatment than the less severe sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Tetracyclines inhibit parathyroid hormone-induced bone resorption in organ culture

Several tetracyclines (minocycline, doxycycline, tetracycline), in levels approximating physiologic concentrations, were found to inhibit parathyroid hormone-induced bone resorption in organ culture; the specificity of this effect was demonstrated by comparison with other (non-tetracycline) types of antibiotics. The ability of tetracyclines to inhibit bone resorption is consistent with the recent proposal by Golub et al. that these antibiotics can inhibit mammalian collagenolytic enzymes by a mechanism unrelated to the drug's antibacterial efficacy, a property which could be therapeutically useful in diseases characterized by excessive collagen breakdown.

Chemotherapy and periodontal disease--a review

Periodontal diseases are common, inflammatory infections of the mouth of microbiological etiology. Therapy traditionally focuses on professional tooth cleaning and debridement. Recent research has investigated the efficacy of antibiotic therapy, as well as the use of various other agents. Although protocols still are being developed, pharmacists can expect increasing use of these medications by dentists in the future.

Effect of combined systemic antimicrobial therapy and mechanical plaque control in patients with recurrent periodontal disease

The aim of the present study was to analyze the effect of systemic antimicrobial therapy and mechanical plaque control in patients with recurrent periodontal disease. 9 patients volunteered for the combined therapy. At a baseline examination they were randomly distributed into 2 groups, one given tetracycline therapy for 2 weeks and the other metronidazole therapy for 1 week. A mechanical plaque control program comprising oral hygiene training, professional cleaning of all teeth and subgingival debridement at diseased sites was carried out at the baseline examination and at all recall visits, i.e. once every month during the first 6 months and then after 9, 12, and 18 months. The results demonstrated clinically and microbiologically that a combination of an initial antimicrobial and a continuous systematic mechanical plaque control program may be a valuable therapeutic approach in a strictly selected group of refractory patients. Recurrent periodontal lesions which still displayed severe inflammation despite renewed conventional therapy showed a marked reduction in probing depths, bleeding and suppuration from the pockets, and further, a reduced presence of spirochetes and motile rods during the trial. The results indicate that the level and longevity of success is also related to whether or not self-performed oral hygiene measures are sufficiently carried out. No superior effect of the combined program could be observed in cooperating patients receiving tetracycline as compared with those given metronidazole.

Effect of long-term tetracycline therapy on human periodontal disease

The present investigation was performed to study the effect of long-term, low dosage tetracycline therapy on advanced periodontal disease in humans. 14 volunteers participated in the trial. Each of the participants had at least 4 pairs of diseased sites around contralateral premolars and incisors with deep pockets and advanced bone loss. The trial extended over a 50-week period and was designed as a double-blind split-mouth study. A Baseline examination included assessments of oral hygiene, gingival conditions, probing depth, attachment level and analysis of the composition of the subgingival microbiota in samples obtained from 8 selected diseased sites. All participants received oral hygiene instruction. In each patient 2 quadrants of the mouth, chosen at random, were treated by scaling and root planing. The 2 remaining quadrants were left unscaled. Following the Baseline examination the patients were randomly distributed into 2 groups of 7 members each. In one of the groups the patients received tetracycline on a daily basis during a 50-week period. The participants of the control group received placebo. Reexaminations were performed 2, 10, 20, 30 and 50 weeks after the Baseline examination. The findings demonstrated that in patients with advanced periodontal disease long-term tetracycline therapy in the absence of scaling resulted in the establishment of a subgingival microbiota almost devoid of motile bacteria and in markedly reduced signs of gingivitis, probing depth and attachment loss. In fact, the alterations observed as a result of tetracycline administration to patients with excellent self-performed plaque control were similar to those obtained by conventional scaling and root planing in the control group.

Microbiological and clinical effects of topical subgingival antimicrobial treatment on human periodontal disease

This study was undertaken to evaluate the microbiological and clinical effects of a subgingivally applied mixture of H2O2-NaCl and NaHCO3 followed by subgingival irrigation with 1% Betadine in the treatment of periodontal disease. 20 adults with moderate to severe periodontal disease were included in a split mouth design study. All patients were given oral hygiene instruction and were subjected to supragingival scaling in all 4 quadrants, and subgingival scaling and root planing of half the dentition. 10 patients were instructed to use the chemical antimicrobial mixture twice a day instead of dentifrice, and also received professional application of the mixture once every 14 days for 3 months in connection with reinstruction in oral hygiene procedures. The remaining 10 patients received oral hygiene instructions combined with professional tooth cleaning without use of chemicals once every 14 days during a 3-month period. The effect of treatment was evaluated by monitoring the subgingival microflora, clinical periodontal parameters, and by computer assisted subtraction analysis of serial standardized radiographs to determine changes in mass of the supporting alveolar bone. The present study revealed that subgingival debridement combined with mechanical plaque control resulted in decreased numbers of subgingival microorganisms including spirochetes and motile rods, and arrested the progressive breakdown of the periodontal tissues. Topical antimicrobial agents used in combination with subgingival scaling further reduced the subgingival microflora and substantially improved early periodontal healing including gain of probing attachment level and gain in radiographic alveolar bone mass during the 12 months of observation. No clinical improvement but a tendency to further periodontal breakdown was found in the unscaled quadrants, even in those which were subjected to a personal application of the topical antimicrobial mixture. This study indicates that professional and personal subgingival application of a mixture of H2O2-NaCl and NaHCo3 will significantly enhance the microbiological and clinical effects of periodontal scaling and root planing. These agents, and the topical mode of antimicrobial therapy seem promising in the management of human periodontal diseases.