Dental caries formation, effect

Controlled and sustained drug delivery has recently begun to make an impression in the area of treatment of dental diseases. Many researchers have demonstrated that controlled delivery of antimicrobial agents, such as chlorhexidine [128-130], ofloxacin [131-133], and metronidazole [134], can effectively treat and prevent periodontitis. The incidence of dental caries and formation of plaque can also be reduced by controlled delivery of fluoride [135,136]. Delivery systems used are film-forming solutions [129,130], polymeric inserts [132], implants, and patches. Since dental disease is usually chronic, sustained release of therapeutic agents in the oral cavity would obviously be desirable. 

Hatta, H., Tsuda, K., Ozeki, M., Kim, M., Yamamoto, T., Otake, S., Hirasawa, M., Katz, J., Childers, N.K., and Michalek, S.M. 1997. Passive immunization against dental plaque formation in humans effect of a mouth rinse containing egg yolk antibodies (IgY) specific to Streptococcus mutans. Caries Res. 31, 268-274. 

The reduction in dental caries as a result of fluoridation of water supplies and use of fluoride containing toothpastes is well known (Shell s and Duckworth 1994). This is clearly linked in part to the fact that the solubility product of fluorapatite is less than that of HAP (Moreno et al. 1977). For a partial replacement of OIT by F ions, the solubility product for Ca5(P04)3(0H)i.xFx is a minimum for x = 0.56 (Moreno et al. 1977). Chow and Banes (2001) and LeGeros (1991) discuss further the effects of F ions on the solubility, rate of dissolution and formation of apatites. Fluoride has also been used in attempts to rebuild bone lost as a result of osteoporosis (see Grynpas and Cheng 1988 and Baud et al. 1988 for references). Fluoride has effects on both bone mineral and cellular activity (Baylink et al. 1970, Banes and Reddi 1979). For example, F ions reduce the rate of dissolution of the mineral in acidic buffers (Grynpas and Cheng 1988). Other effects on the mineral will be mentioned later. 

Chlorhexidine initially was used as a general disinfectant because of its broad antibacterial action (9). It was later shown to inhibit dental caries and reduce the formation of dental plaque (10). In vitro inhibition studies have shown chlorhexidine to be effective against species found in infected root canals such as Enterococcus faecalis (11) and Streptococcus mutans (12), and because of this, it was introduced as an endodontic irrigant in the early 1960 s (10). Chlorhexidine is increasingly being incorporated into endodontic materials due to its ability to increase antimicrobial properties and improve prognosis. 

There are a certain number of options to control and reduce dental caries, the biggest problem in tooth care. The use of fluoride salts is one of the most effective methods to prevent or slow down demineralization that causes tooth decay [16,17]. The action of fluoride can be explained by its antimicrobial action, its interaction with enamel to form a fluorinated hydroxyapatite compound (hydroxyfluorapa-tite or fluorapatite Ca5(P04)3F) by substitution of an hydroxyl ion in hydroxyapatite Ca5(P04)3(0H), which is more resistant to add than enamel on its own, and its repairing effect by formation of calcium and phosphate, which ranineralize the tiny lesions in which caries begin. 

Nancollas GH, Johnsson MAS Calculus formation and inhibition. Adv Dent Res 1994 8 307-311. White DJ Dental calculus recent insights into occurrence, formation, prevention, removal and oral health effects of supragingival and subgingival deposits. Eur J Oral Sci 1997 105 508-522. Pattanapom K, Navia JM The relationship of dental calculus to caries, gingivitis, and selected salivary factors in 11- to 13-year-old children in Chiang Mai, Thailand. J Periodontal 1998 69 955-961. 

Giertsen, E. (2004). Effects of mouthrinses with tri-closan, zinc ions, copolymer, and sodium lauryl sulphate combined with fluoride on acid formation by dental plaque in vivo. Caries Research, 38, 430. 

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