Fluctuations in tap water fluoride levels: a potential problem for practitioners.

Weekly water samples were obtained from the tap water at the Dental Branch of the University of Texas Health Science Center at Houston. Analysis of these water samples showed significant fluctuations in fluoride levels from 1988 to 1991. This inconsistency in water fluoride content makes it very difficult for health care providers to prescribe and maintain an optimal fluoride supplementation to children. Based on results from this study, more rigorous surveillance and monitoring of water fluoridation in Houston is recommended.

Kinin generation in the gingival inflammatory response to topically applied bacterial lipopolysaccharides.

A water-soluble lipopolysaccharide from Salmonella enteritidis and a phenol-soluble lipopolysaccharide from Leptotrichia buccalis were applied topically to the healthy marginal gingivae of beagle dogs. Saline was applied to contralateral areas as an internal control. Increases in vascular permeability were monitored by measurement of gingival fluid, and the collected gingival fluid samples were assayed for kininogenase and kinin activities. Both lipopolysaccharides induced an inflammatory response, as indicated by increased gingival fluid flow. Kininogenase-kinin activities paralleled the increases in gingival fluid flow, with the highest values being associated with peak increases in gingival fluid. The results indicate that both lipopolysaccharides, although different in lipid solubility, penetrate healthy sulcular epithelium and initiate an inflammatory response which is mediated in part by the kallikrein-kinin system. Interrelationships between this system and other inflammatory mediators suggest that kinin generation not only plays a role in the early phases of acute gingival inflammation, but may also contribute to the activation of other mediators appearing later in the response and in chronic inflammatory lesions.

Principles of anti-infective therapy.

Antimicrobial drugs, along with competent surgical procedures, provide an effective means for restoration of oral health. In dentistry, antibiotics are indicated for either treatment of acute infections or for prophylactic coverage of patients at risk for developing bacterial endocarditis or other infections as the result of bacteremia caused by dental procedures. Whenever possible, a bactericidal agent is preferred because of greater effectiveness and less reliance on host defense mechanisms. For maximal effectiveness of antibiotic therapy of orodental infections, several factors must be evaluated in choosing an antibiotic: (1) antibacterial spectrum and specificity of the agent; (2) degree of bacterial resistance reported for the antibiotic; (3) concentrations achieved at various sites; (4) age, type, and extent of infection; and (5) various host factors.

Use of antibiotics in dental practice.

Penicillin G administered parenterally or penicillin V administered orally are currently the antibiotics of choice for treatment of dental infections of usual etiology. Infections caused by penicillinase-producing staphylococci or those involving gram-negative bacteria should be treated with a penicillinase-resistant penicillin or an ampicillin-like derivative, respectively. Erythromycin is a second-choice bacteriostatic antibiotic, becoming first choice for treating dental infections in patients allergic to penicillin. The cephalosporins, similar in action to ampicillin-like penicillin derivatives, may be used with caution in patients who have exhibited delayed-type allergic reactions to penicillin and when erythromycin cannot be used. Their lack of advantage over other agents, and their cost, precludes routine use for usual dental infections. Clindamycin administered orally or lincomycin administered parenterally are reserve antibiotics indicated for treatment of bone infections and/or anaerobic infections refractory to commonly used antibiotics. Tetracyclines are, at best, third-choice agents for usual dental infections. However, they are useful for cases of acute necrotizing ulcerative gingivitis requiring systemic antibiotic therapy when penicillin is precluded. Vancomycin and streptomycin are used prophylactically for prevention of infective endocarditis in patients with prosthetic heart valves. Nystatin remains a first-choice agent for treatment of oral candidal infections. Ketoconazole, an orally active systemic antifungal agent, may be used for monilial infections of the oral cavity refractory to nystatin. Chemotherapy of viral infections is difficult because of the timing of events of the disease process versus appearance of clinical symptoms and lack of effective agents with selective toxicity. Herpes infections of the oral cavity have been treated--with limited success--with idoxuridine. Acyclovir, a newer antiviral drug, offers little clinical benefit for herpes infections in usually healthy patients but may be of value for treating such infections in immunocompromised patients. All antimicrobial agents may cause adverse reactions of varying degrees of severity. Most orally administered antibiotics may cause gastrointestinal disturbances. Superinfections occur with broad-spectrum antibiotics and a severe form of superinfection, antibiotic-associated colitis, has occurred with almost all antibiotics. Allergic reactions of all degrees of severity can occur with most antibiotics. The penicillins, followed by the cephalosporins and tetracyclines, are most frequently implicated in these reactions.(ABSTRACT TRUNCATED AT 400 WORDS)

Exocytosis of polymorphonuclear leukocyte lysosomal contents induced by dental plaque.

Rabbit polymorphonuclear leukocytes were incubated with a sonically treated suspension of pooled dental plaque to determine if the plaque would induce release of lysosomal enzymes from the polymorphonuclear leukocytes. Cells incubated with plaque at 37 degrees C released significantly greater amounts of the lysosomal enzymes, beta-glucuronidase and lysozyme, than did cells incubated with plaque at 0 degrees C or without plaque at 37 degrees C. This response was both dose and time dependent. Release of the cytoplasmic enzyme lactate dehydrogenase was minimal, and there were no significant differences in lactate dehydrogenase release between cells at 0 and 37 degrees C, or without plaque. These results indicate that dental plaque can induce the selective release of lysosomal enzymes, which could be involved in the periodontal injury produced by dental plaque.