Recent epidemiological surveys have shown a reduction in dental caries in children, while highlighting the problem of coronal and root surface decay in elderly populations. As more teeth are retained and edentulism declines, more surfaces will be at risk in the adult population than ever before. The overall objective of this proposal is to reduce the extent of the caries process (in particular root surface caries) by primary and secondary prevention when the etiology of the disease has been clarified. By combining the information obtained in both the laboratory and clinic and refining the model system used to simulate the caries process, the ideal preventive and treatment strategies for root surface caries should be elucidated. This proposal intends to use both in vitro and in situ models to describe the disease process, and to determine the preventive agents most suited for use in root surface caries prevention. Specifically, we intend to (1) determine the level of fluoride needed to form root surface lesions with a mineralized surface layer, (2) test the hypothesis that remineralization occurs on remaining mineral and not demineralized matrix, (3) evaluate the resistance of remineralized lesion to further acid attack, (4) test whether fluoride present in the demineralizing or remineralizing cycle is most important, (5) determine the ability of existing fluoride agents to inhibit root surface caries in an in situ model. In vitro pH cycling experiments as well as the intraoral crown model assess episodic periods of demineralization and remineralization as opposed to continuous. The sensitivity of the single-section technique will allow before and after measurements on the same section. Both polarized light microscopy and microradiography will be used in qualitative and quantitative analyses. These studies should determine the usefulness of current fluoride preventive agents, and thus address the question of whether new and/or modified agents and vehicles are needed to efficiently prevent root surface caries.

National Institute of Health (NIH)
National Institute of Dental & Craniofacial Research (NIDCR)
Specialized Center (P50)
Project #
Application #
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Itthagarun, A; King, N M; Wefel, J S et al. (2001) The effect of fluoridated and non-fluoridated rewetting agents on in vitro recurrent caries. J Dent 29:255-73
Hsu, C Y; Jordan, T H; Dederich, D N et al. (2001) Laser-matrix-fluoride effects on enamel demineralization. J Dent Res 80:1797-801
Hsu, C Y; Jordan, T H; Dederich, D N et al. (2000) Effects of low-energy CO2 laser irradiation and the organic matrix on inhibition of enamel demineralization. J Dent Res 79:1725-30
Cai, L; Wei, G X; van der Bijl, P et al. (2000) Namibian chewing stick, Diospyros lycioides, contains antibacterial compounds against oral pathogens. J Agric Food Chem 48:909-14
Donly, K J; Segura, A; Wefel, J S et al. (1999) Evaluating the effects of fluoride-releasing dental materials on adjacent interproximal caries. J Am Dent Assoc 130:817-25
Donly, K J; Segura, A; Kanellis, M et al. (1999) Clinical performance and caries inhibition of resin-modified glass ionomer cement and amalgam restorations. J Am Dent Assoc 130:1459-66
Li, X C; van der Bijl, P; Wu, C D (1998) Binaphthalenone glycosides from African chewing sticks, Diospyros lycioides. J Nat Prod 61:817-20
Hsu, C Y; Donly, K J; Drake, D R et al. (1998) Effects of aged fluoride-containing restorative materials on recurrent root caries. J Dent Res 77:418-25
Li, X C; Cai, L; Wu, C D (1997) Antimicrobial compounds from Ceanothus americanus against oral pathogens. Phytochemistry 46:97-102
Heilman, J R; Jordan, T H; Warwick, R et al. (1997) Remineralization of root surfaces demineralized in solutions of differing fluoride levels. Caries Res 31:423-8

Showing the most recent 10 out of 11 publications