Microhardness and Cutting Resistance in Enamel of Primary Molars Among Various Caries Experience Groups In Vitro

Khositphanthawong Nawaporn, Sirimaharaj Varisara, Wanachantararak Sitthichai

Published Online: Jan 27, 2022 DOI 10.14456/cmdj.2022.5

Objectives: To investigate cutting resistance, microhardness, and their correlations with primary teeth enamel, from different caries experience groups.

Methods: Forty-five extracted primary molars were divided equally into three groups using the dmft/dmft+DMFT index: low, moderate, and high caries experience groups. Each tooth was divided into 2 parts to test cutting resistance and microhardness. All data were compared statistically between groups with different caries experiences using the one-way ANOVA. The correlations were investigated using the Spearman’s and the Pearson’s correlation.

Results: The high caries experience group had significantly lower microhardness of enamel (295.8±12.73 Vickers Hardness Number (VHN)) than the moderate and low caries experience groups (315.01±16.13 VHN; p=0.001 and 325.96±9.91 VHN; p<0.001, respectively). The cutting resistance of enamel from the high caries experience group (87.23±15.06 grams) was also significantly less than those from the moderate and low caries experience groups (112.78±16.02 grams; p=0.002, and 111.67±24.75 grams; p=0.003, consecutively). There were negative correlations between caries experience and cutting resistance (r=-0.46; p=0.002) and between caries experience and microhardness (r=-0.71; p<0.001) but a positive correlation between cutting resistance and microhardness (r=0.39; p=0.009).

Conclusions: Enamel of primary teeth from the high caries experience group had less microhardness and cutting resistance than those of the moderate and low caries experience groups.

Hardness primary tooth caries experience cutting resistance enamel

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Khositphanthawong N, Sirimaharaj V, Wanachantararak S. Microhardness and Cutting Resistance in Enamel of Primary Molars Among Various Caries Experience Groups In Vitro: Original articles. CM Dent J [Internet]. 2022 Jan 27 [cited 2024 Apr 29];43(1):49-56. Available from: https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=161

Khositphanthawong, N., Sirimaharaj, V. & Wanachantararak, S. (2022). Microhardness and Cutting Resistance in Enamel of Primary Molars Among Various Caries Experience Groups In Vitro. CM Dent J, 43(1), 49-56. Retrieved from: https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=161

Khositphanthawong, N., Sirimaharaj Varisara and Wanachantararak Sitthichai. 2022. "Microhardness and Cutting Resistance in Enamel of Primary Molars Among Various Caries Experience Groups In Vitro." CM Dent J, 43(1), 49-56. https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=161

Khositphanthawong, N. et al. 2022. 'Microhardness and Cutting Resistance in Enamel of Primary Molars Among Various Caries Experience Groups In Vitro', CM Dent J, 43(1), 49-56. Retrieved from https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=161

Khositphanthawong, N., Sirimaharaj, V. and Wanachantararak, S. "Microhardness and Cutting Resistance in Enamel of Primary Molars Among Various Caries Experience Groups In Vitro", CM Dent J, vol.43, no. 1, pp. 49-56, Jan. 2022.

Khositphanthawong Nawaporn, Sirimaharaj Varisara, Wanachantararak Sitthichai "Microhardness and Cutting Resistance in Enamel of Primary Molars Among Various Caries Experience Groups In Vitro." CM Dent J, vol.43, no. 1, Jan. 2022, pp. 49-56, https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=161