Remineralizing Effect of Nanohydroxyapatite Toothpaste on Caries- Like Lesions in Primary Teeth (An in Vitro Study)

Abstract

OBJECTIVES:To evaluate in vitro, the effect of nano-hydroxyapatite (NHA) toothpaste in comparison with a fluoridated toothpaste on remineralization of caries like lesion in the enamel of primary teeth. MATERIALS AND METHODS: sixty sound primary anterior teeth were coated with nail varnish; leaving squares of 3x3 mm on facial surface uncovered. Forty teeth were divided into two groups where group (I) n=20 treated by NHA toothpaste and group (II) n=20 treated by fluoridated toothpaste containing sodium monofluorophosphate (1450 ppm F). They were examined with Vickers Microhardness device. The remaining 20 teeth were divided into two groups (III and IV). They were sectioned longitudinally in a labiolingual direction into two equal halves, mesial half not treated (sub group IIIA) and distal half treated by NHA (sub group IIIB). Mesial half not treated (sub group IVA) and distal half treated by fluoridated toothpaste (sub group IVB). Specimens were evaluated quantitatively and qualitatively with Polarized Light Microscope. RESULTS:The microhardness of teeth significantly decreased following acid exposure but increased again in both groups after exposure to toothpastes. The NHA toothpaste non-significantly increased the percent change of microhardness by 1.65 times than fluoridated toothpaste (p = 0.06). The percent differences in lesion depth between test group IIIB and its control group IIIA was -58.96 ± 9.04, whereas between test group IVB and its control IVA was -56.26 ± 17.43. There was no statistically significant difference between the two values (P=0.67). CONCLUSION: NHA and fluoridated toothpastes are equally effective as remineralizing materials for the enamel.

The Mediating Role of Job Satisfaction in the Relationship between Organizational Culture and Job Commitment among Employees in the Ministry of Education in the Sultanate of Oman

“…Multiple linear regression analysis was also conducted to examine the impact of organizational culture dimensions (values, beliefs, norms, expectations) on job commitment, and the results were as follows: The results in the above table (17) indicate a statistically significant effect of organizational culture dimensions (values, beliefs, norms, expectations) on job commitment. The correlation coefficient (R=0.739) suggests a statistically significant relationship between the combined independent variables (values, beliefs, norms, expectations) and the dependent variable (job commitment).…”