Evaluation of ultrasonic scaling unit waterline contamination after use of chlorine dioxide mouthrinse lavage.

BACKGROUND: An infection control problem in dental operatories which is not fully controlled is waterline contamination by heterotrophic mesophilic bacteria. These bacteria are present in water supplies as a planktonic phase and adhere to the lumen of tubings as a biofilm comprised of their external cell surface glycocalyx and by production of extracellular carbohydrate polymers. The adherent film is most difficult to remove. The accumulated planktonic phase can be reduced significantly by flushing water from the lines before use in patient treatment, but will return when the equipment is idle through the accumulation of more planktonic phase and by slough of the biofilm surface-adsorbed phase not yet enmeshed in the carbohydrate matrix. Chlorine dioxide has antimicrobial activity against many bacteria, spores, and viruses. It is used in water supply treatment as a disinfectant and slime preventive and has an advantage over chlorine in that carcinogenic trihalomethanes are not generated. METHODS: This study compared use of phosphate buffer-stabilized chlorine dioxide (0.1%) mouthrinse as a lavage in ultrasonic dental scaler units with the use of tap water as a control. Sterile water flushed through the units onto heterotrophic plate count (HPC) sampler plates was cultured 7 days at room temperature and colonies were counted at 12x. One test and one control unit were used for biopsy of internal tubing and scanning electron microscopy imaging. RESULTS: The HPC counts, in colony forming units (CFU)/ml, were reduced 3- to 5-fold by flushing tap water through the units, but they returned after units were idle overnight. When phosphate-buffered chlorine dioxide mouthrinse was used as a lavage, CFU/ml were reduced 12- to 20-fold. Holding chlorine dioxide in waterlines overnight reduced recurrent buildup compared to water (P <0.05). Scanning electron microscopy images indicated a significant reduction of biofilm coverage by chlorine dioxide as compared to water (P<0.001). CONCLUSIONS: Phosphate-buffered chlorine dioxide mouthrinse was effective in these short-term trials for control of waterline contamination in ultrasonic dental scaling units. It should prove as useful in dental professional waterline applications as it has in industrial uses for biofilm control.

A mucosal irritancy test device for intraoral use in dogs.

The objective of this investigation was to conduct, in dogs, a 6-hour acute mucosal irritation study of a new bioerodible treatment. The main problem was to retain the test drug in situ without extraneous irritation from the retention device. A buccal cup was machined from acrylic with a chamber capacity of 0.025 ml and a flange that could be ligated to a tooth. Ten female retired breeder beagles, 7 to 8 years old, with naturally occurring moderate periodontitis were examined and the upper canine teeth scaled to remove plaque and calculus. One week later the buccal cups were placed at the gingival margin of the upper canine teeth and fixed in place with wire ligature passing through holes in the flange and around the tooth, engaging shallow nicks made in the enamel near the gingival margin so the wire would not slide up and down. The buccal cup was further stabilized with glass ionomer cement placed on the crown and over the outer surface of the cup. Buccal cups were loaded with test, placebo, or no ointment by technicians in a scheme to which examiners were blind. Hourly examinations were made, and after 6 hours the cups were removed and gingival mucosa scored for irritation by a previously described method. All dogs tolerated the test and retained the cups for 6 hours. There was no mucosal irritation from the empty cups. We conclude that this new device can be used successfully for testing new agents for short-term mucosal irritancy.

Alterations of fibroblast metabolism in early ligature-induced periodontitis in the cynomolgus monkey.

Cellular and biochemical observations were made of fibroblasts harvested from ligature-induced periodontitis and treated gingivitis areas in four adult female cynomolgus monkeys (Macaca fascicularis) to define the changes that occur in the early periodontitis lesion. Compared with fibroblasts from the treated sites, fibroblasts from the diseased areas had a significantly higher rate of proliferation, produced about two-thirds the amount of total protein and collagen, and failed to respond to TGF-beta, which normally stimulates extracellular matrix formation in mesenchymal cells. The diseased cells were also deficient in the activity of poly(ADP-ribose) synthetase, an enzyme involved in the repair of DNA breaks such as occur from the insults of superoxide and other active radicals present in inflamed areas. Although the precise nature of these biochemical defects is not fully elucidated, they may have an important bearing on chronic periodontitis cases with a "downhill" course.

Clinical and light microscopic observations of gingivitis and early ligature-induced periodontitis in the cynomolgus monkey.

Clinical and histological observations were made on gingivitis and ligature-induced periodontitis in 4 adult female cynomolgus monkeys (Macaca fascicularis) to define the changes occurring in the early periodontitis lesion. Silk ligatures were tied around selected posterior teeth and replaced weekly for 4 weeks. The changes from gingivitis to periodontitis induced by ligation, and back to a state of clinical health after ligature removal, scaling and polishing, were characterized by Plaque Index, Gingival Index, probing pocket depth, attachment loss, and histologic evaluation. A mild, chronic marginal gingivitis was the normal finding in the gingiva of posterior teeth. The inflammatory infiltrate in the connective tissue contained primarily lymphocytes. Hygienic measures once a week reduced the amount of infiltrate and the epithelial proliferation, but did not eliminate it. Placement of silk ligatures rapidly changed the clinical picture to a moderate or severe gingivitis, which presented an almost bizarre response of sulcular and oral epithelium, with an increase in polymorphonuclear neutrophil infiltration. Within 2 weeks there was significant probing attachment loss. The clinical response on removal of ligatures and plaque was almost as rapid as the onset. The animal model is useful for manipulating variables in ways not possible in the study of human periodontitis.

Epidemiology and prevention of periodontal disease in individuals with diabetes.

OBJECTIVE: This article reviews the epidemiological evidence of the relationship between diabetes and periodontal disease, possible physiological mechanisms for the association, and effects of interventions on the occurrence and severity of periodontal disease among individuals with diabetes. RESEARCH DESIGN AND METHODS: A comprehensive qualitative review of published literature in the area was performed. RESULTS: Much of the research in this area was found to contain methodological problems, such as failing to specify the type of diabetes, small sample sizes, and inadequate control of covariates such as age or duration of diabetes. CONCLUSIONS: Trends indicate that periodontal disease is more prevalent and more severe among individuals with diabetes. This trend may be modified by factors such as oral hygiene, duration of diabetes, age, and degree of metabolic control of diabetes. Generally, poor oral hygiene, a long history of diabetes, greater age, and poor metabolic control are associated with more severe periodontal disease. The association of diabetes and periodontal disease may be due to numerous physiological phenomena found in diabetes, such as impaired resistance, vascular changes, altered oral microflora, and abnormal collagen metabolism. With some modifications, the same prevention and treatment procedures for periodontal disease recommended for the general population are appropriate for those with diabetes. People with diabetes who appear to be particularly susceptible to periodontal disease include those who do not maintain good oral hygiene or good metabolic control of their diabetes, those with diabetes of long duration or with other complications of diabetes, and teenagers and pregnant women.

The healing of atraumatic and traumatic incisions in the gingivae of monkeys.

Standard wounds of simple incision and trauma were made in the gingivae of monkeys. The healing from the 1st to the 21st day was described clinically, histologically, physically and biochemically. There were no major clinical differences, but both atraumatic and traumatic wounds have reactions in the periodontium to be considered in postoperative care.

Regeneration and repair after biologic treatment of root surfaces in monkeys. II. Proximal surfaces posterior teeth.

THE HEALING of a new attachment procedures was evaluated in monkeys. Standard flap curettage procedures were made in posterior segments having previously created periodontal pockets. The diseased root surfaces were treated with sodium deoxycholate (2%) and human plasma fraction Cohn IV1 (5%), applied to experimental sites for 1 minute each. Control surfaces were similarly treated with phosphate buffered saline. The healing at 10 weeks postoperatively was described clinically, histologically, and by histometrics. There was a significant increase in connective tissue new attachment in experimental sites, compared to controls.

A microbiological analysis of human early carious and non-carious fissures.

The fissure sampling technique consisted of removing the fissure using a bur in a high-speed handpiece with water spray and then suctioning the fissural contents and the water spray into a sterile sampling container. Sixty-eight teeth were sampled. Total bacterial counts, total streptococcal counts, and counts of Streptococcus mutans, Streptococcus sanguis, Streptococcus faecalis, Actinomyces viscosus, and lactobacilli were performed on the fissural samples. There was a four-fold increase in the total number of microorganisms recovered from carious (N = 48) compared to non-carious (N = 20) fissures. S. mutans was the only microorganism common to all carious fissures.

Regeneration and repair after biologic treatment of root surfaces in monkeys.

The healing of a new attachment procedure was evaluated in monkeys. Standard pedicle wounds similar to reverse bevel flaps were made in previously created periodontal pockets. The diseased root surfaces were treated with sodium deoxycholate (2%) and human plasma fraction Cohn IV (5%), applied to experimental sites for 1 minute each. Control surfaces were similarly treated with phosphate buffered physiological saline. The healing from the first to the 21st day was described (1) clinically, (2) histologically, (3) by rupture strength, and (4) by collagen production assays. All control sites healed with a dentogingival junction comprised only of junctional epithelium. Most experimental sites healed by means of junctional epithelium and some connective tissue new attachment at the apical extent of the wounds.

The performance of autoclaved high-speed dental handpieces.

High-speed dental handpieces, which are used so extensively in modern dental practice, may be a source of cross-contamination between patients. A standard autoclave procedure of 121 C for 15 minutes will sterilize the handpieces evaluated in this report. The performance in a standardized laboratory trial showed deterioration of speed in the simulated three-month period. Clinical evaluations for three months showed some minor mechanical problems. These dental handpieces should be used in conjunction with a formal daily and three-month maintenance program.

The location of the periodontal probe tip in health and disease.

The periodontal probe is used clinically to measure pocket depth and the level of periodontal attachment. In order to be a more reliable, noninvasive method of assessment, it is necessary to investigate the position of the tip of the probe when at rest in the dentogingival junction. Probes were assessed for accuracy, and those closest to a standard millimeter scale were used to make pressure-cast, gold-coated, acrylic replicas. The replicas were placed in the gingival crevice of Rhesus monkeys with normal gingiva and with experimentally-induced gingivitis and periodontitis. Clinical, histologic, and histometric evaluations were made in block sections. In normal gingiva and in areas of gingivitis the probe tip stopped at the base of the crevice and was contained within epithelium. In periodontitis the probe sometimes penetrated the epithelium and stopped at the level of the connective tissue attachment. Even with gentle probing there was slight tearing and distortion of the gingiva at the base of the pocket. It was concluded that probing depth estimates indicated the level of a healthy dentogingival junction but did not differentiate between epithelial and connective tissue attachment.

Regeneration and Repair After Biologic Treatment of Root Surfaces in Monkeys: I. Facial Surfaces Maxillary Incisors,.

The healing of a new attachment procedure was evaluated in monkeys. Standard pedicle wounds similar to reverse bevel flaps were made in previously created periodontal pockets. The diseased root surfaces were treated with sodium deoxycholate (2%) and human plasma fraction Cohn IV1 (5%), applied to experimental sites for 1 minute each. Control surfaces were similarly treated with phosphate buffered physiological saline. The healing from the first to the 21st day was described (1) clinically, (2) histologically, (3) by rupture strength, and (4) by collagen production assays. All control sites healed with a dentogingival junction comprised only of junctional epithelium. Most experimental sites healed by means of junctional epithelium and some connective tissue new attachment at the apical extent of the wounds.