Development of caries-like lesions in human and bovine dentin compared to natural caries
Desenvolvimento de lesões artificiais de cárie em dentina humana e bovina comparada a lesões de cárie natural
Rehder-Neto, Francisco Carlos; Menezes, Márcio de; Chimello, Daniela Thomazatti; Serra, Mônica Campos
Rev. odontol. UNESP, vol.39, n3, p.163-168, 2010
Abstract
Due to the complexity, ethical aspects and high costs involving clinical experiments on dental caries, in vitro studies have been considered as an alternative option to clinical researches. The purpose of this study was to compare artificial caries-like lesions in human and bovine dentin to natural caries in human dentin (CT). Fifteen specimens of human dentin with natural caries, 45 specimens of human dentin (H), and 45 specimens of bovine dentin (B) were flattened and polished. The specimens from groups H and B were submitted to three different protocols of pH cycles: 8 (H8 and B8), 12 (H12 and B12), and 16 cycles (H16 and B16). Each cycle consisted of immersion of the specimens for 6 hours in a demineralising solution and for 18 hours in a remineralising solution. After the cariogenic challenge, the Knoop microhardness (KHN) was determined at 30, 60, 90, 120 and 150 μm from the lesion surface. The Analysis of Variance showed a significant effect of the interaction cycle-depth. The Student’s t-test was employed to compare the mean values of KHN from the substrate with natural caries to the values of KHN of each cycle of the experimental groups (H or B), at each depth. The pH-cycling models closest to natural caries were group B8, for bovine dentin and group H16, for human dentin. Within the conditions of the present study, it can be concluded that the use of both human and bovine substrates can be considered a viable alternative to the development of artificial caries lesions.
Keywords
Microhardness, human dentin, bovine dentin, dental caries
Resumo
Dada a complexidade, aspectos éticos e custos envolvidos na condução de experimentos clínicos relacionados a cárie dental, estudos in vitro têm sido uma alternativa às pesquisas clínicas. O objetivo deste estudo foi avaliar o desenvolvimento de lesões artificiais de cárie em dentina humana e bovina, comparado à lesões de cárie natural em dentina humana (CT). Quinze fragmentos de dentina humana naturalmente cariada, 45 fragmentos de dentina humana (H) e 45 fragmentos de dentina bovina (B) foram planificados e polidos. Os espécimes dos grupos H e B foram então submetidos a três protocolos de ciclos de pH: 8 (H8 e B8), 12 (H12 e B12) e 16 ciclos (H16 e B16). Após o desafio cariogênico, valores de microdureza Knoop (KHN) foram obtidos a 30, 60, 90, 120 e 150 µm da superfície das lesões. A Análise de Variância mostrou efeito significativo da interação ciclo-profundidade. O teste t-Student foi empregado para comparar as médias de KHN do substrato naturalmente cariado (CT) em relação a cada desafio cariogênico desenvolvido nos grupos H e B, em cada profundidade. Os modelos de ciclos de pH que mais se aproximaram em termos de microdureza das lesões de cárie natural foram o grupo B8, para dentina bovina e o grupo H16, para dentina humana. Dentro das condições do presente estudo, pode-se concluir que a utilização tanto de substrato humano quanto bovino pode ser considerada uma alternativa viável para o desenvolvimento de lesões de cárie artificial.
Palavras-chave
Microdureza, dentina humana, dentina bovina, cárie dental
References
1. Feagin F, Koulourides T, Pigman W. The characterization of enamel surface demineralisation, remineralisation and associated hardness changes in human and bovine material. Arch Oral Biol. 1969; 14: 1407-17.
2. Featherstone JDB, Duncan JF, Cutress TW. A mechanism for dental caries based on chemical processes and diffusion phenomena during in-vitro caries simulation on human tooth enamel. Arch Oral Biol. 1979; 24: 101-12.
3. Arends J, Schuthof J, Jongebloed WG. Lesions depth and microhardness indentations on artificial white spot lesions. Caries Res. 1980; 14: 190-5.
4. Arends J, Schuthof J. Microhardness and lesion depth studies of artificial caries lesions: a comparison of gelatin and HEC based systems. J Biol Buccale. 1980; 8: 175-81.
5. Featherstone JDB, Mellberg JR. Relative rates of artificial carious lesions in bovine, ovine and human enamel. Caries Res. 1981; 15: 109‑14.
6. Featherstone JDB, Ten Cate JM, Shariati M, Arends J. Comparison of artificial caries like-lesions by quantitative microradiography and microhardness profiles. Caries Res. 1983; 17: 385-91.
7. Edmunds DH, Whittaker DK, Green RM. Suitability of human, bovine, equine, and ovine tooth enamel for studies of artificial bacterial carious lesions. Caries Res. 1988; 22: 327-36.
8. Wefel JS, Heilman JR, Jordan TH. Comparisons of in vitro root caries models. Caries Res. 1995; 29: 204-9.
9. Amaechi BT, Higham SM, Edgar WM. Factors affecting development of carious lesions in bovine teeth in vitro. Arch Oral Biol. 1998; 43: 619-28.
10. Featherstone, JDB. The continuum of dental caries: evidence for a dynamic disease process. J Dent Res. 2004; 83(Special Issue C):C39‑42.
11. Kidd EAM, Fejerskov O. What constitutes dental caries? Histopatology of carious enamel and dentin related to the action of cariogenic biofilms. J Dent Res. 2004; 83(Special Issue C): C35-38.
12. Argenta RM, Tabchoury CP, Cury JA. A modified pH-cycling model to evaluate fluoride effect on enamel demineralization. Braz Oral Res. 2003; 17: 241-6.
13. de Menezes M, Turssi CP, Faraoni-Romano JJ, Serra MC. Susceptibility of bleached enamel and root dentin to artificially formed caries‑like lesions. Am J Dent. 2007; 20: 173-6.
14. Mellberg JR. Hard-tissue substrates for evaluation of cariogenic and anti-cariogenic activity in situ. J Dent Res. 1992; 71(Special Issue): 913‑19.
15. Hara AT, Queiroz CS, Paes Leme AF, Serra MC, Cury JA. Caries progression and Inhibition in human and bovine root dentin in situ. Caries Res. 2003; 37: 339-44.
16. McIntyre JM, Featherstone JDB, Fu J. Studies of dental root surface caries. 1: comparison of natural and artificial root caries lesions. Aust Dent J. 2000; 45: 24-30.
17. Kawasaki K, Ruben J, Tsuda H, Huysmans MCDNJM, Tagaki O. Relationship between mineral distributions in dentin lesions and subsequent remineralisation in vitro. Caries Res. 2000; 34: 395-403.
18. Hara AT, Magalhães CS, Serra MC, Rodrigues Jr AL. Cariostatic effect of fluoride-containing restorative systems associated with dentifrices on root dentin. J Dent. 2002; 30: 205-12.
19. Mukai Y, Ten Cate JM: Remineralisation of advanced root dentin lesions in vitro. Caries Res. 2002; 36: 275-80.
20. Marquezan M, Corrêa FN, Sanabe ME, Rodrigues Filho LE, Hebling J, Guedes-Pinto AC, et al. Artificial methods of dentine caries induction: a hardness and morphological comparative study. Arch Oral Biol. 2009; 54: 1111-7.
21. Hara AT, Queiroz CS, Giannini M, Cury JA, Serra MC. Influence of the mineral content and morphological pattern of artificial root caries lesion on composite resin bond strength. Eur J Oral Sci. 2004; 112: 67-72.
22. de Freitas PM, Turssi CP, Hara AT, Serra MC. Monitoring of demineralized dentin microhardness throughout and after bleaching. Am J Dent. 2004; 17: 342-6.
23. Vieira A, Hancock R, Dumitriu M, Schwartz M, Limeback H, Grynpas M. How does fluoride affect dentin microhardness and mineralization? J Dent Res. 2005; 84: 951-7.
24. Hara AT, Queiroz CS, Freitas PM, Giannini M, Serra MC, Cury JA. Fluoride release and secondary caries inhibition by adhesive systems on root dentin. Eur J Oral Sci. 2005; 113: 245-50.
25. Montgomery DC. Design and analysis of experiments. New York: John Wiley & Sons; 1997.
26. Barbour ME, Rees JS. The laboratory assessment of enamel erosion: a review. J Dent. 2004; 32: 591-602.
27. Herkströter FM, Witjes M, Ruben J, Arends J. Time dependency of microhardness indentations in human and bovine dentin compared with human enamel. Caries Res. 1989; 23: 342-4.
28. Dutra-Correa M, Anauate-Netto C, Arana-Chavez VE. Density and diameter of dentinal tubules in eatched and non-eatched bovine dentin examined by scanning electron microscopy. Arch Oral Biol. 2007; 52: 850-5.
29. Nanci A. Ten Cate´s oral histology: development, structure and function. Mosby: St. Louis 2003.
Facebook
Google+
Twitter
LinkedIn
Mendeley
StumbleUpon
CiteULike
Reddit
Email