Comparison of remineralizing effect of organic and inorganic fluoride by evaluation of microhardness and quantitative analysis of calcium and phosphorus ratio on enamel surface: an in-vitro study

Main Article Content

Lokam Karthik Prasad
Khwaja Moinuddin MD
Nagamaheshwari X
Uday Kumar P
Shekar K
Mamta Kaushik



Enamel is a highly mineralized tissue of the body which is composed of 96% inorganic salts and 4% organic matter. Enamel is permeable to water and ions, particularly cations and low molecular weight substances. The enamel continues to mature even after eruption with mineral replacing protein. Recently, the interest on the development of calcium phosphate-based remineralization technology has been increased that led to the development of various remineralizing agents like Fluoride, CPP-ACP (Tooth Mouse plus), Bioglass (Novamin), Ozone, Xylitol, Sensistat etc.


Aim of the present in vitro study was to evaluate and compare the remineralizing effect of Organic fluoride (AmF) and inorganic fluoride (NaF) by evaluating Vickers microhardness and quantitative analysis of Calcium and Phosphorus ratio on enamel surface using Scanning Electron Microscope-Energy Dispersive X-ray analysis.

Materials and methods

Sixteen maxillary central incisors were decoronated at the cementoenamel junction and mounted in cylindrical moulds filled with self-cure acrylic resin. Artificial demineralized lesions were created on the enamel surface by suspending them in 0.1 M Citric acid buffer at pH of 3.2 for 72 hrs. The samples were then randomly divided into two groups and labelled, Group A – remineralized with NaF for 3 minutes twice daily for one week and Group B - remineralized with AmF for 3 minutes twice daily for one week. Microhardness and SEM-EDX analysis were done before demineralization, after demineralization and after remineralization.


Data were analyzed by comparing the mean values between the groups using independent sample t-test. The intra-group analysis was done using repeated-measures ANOVA with posthoc Bonferroni test, and a p-value of <0.05 was considered statistically significant.


OrganicFluoride resulted in better remineralization than inorganic Fluoride. After remineralization for one week, enamel samples treated with AmF demonstrated a statistically significant increase in mean microhardness and Ca:P ratio when compared to enamel samples treated with NaF.

Article Details

How to Cite
Karthik Prasad, L. ., MD, K. M., X, N., P, U. K., K, S., & Kaushik, M. (2020). Comparison of remineralizing effect of organic and inorganic fluoride by evaluation of microhardness and quantitative analysis of calcium and phosphorus ratio on enamel surface: an in-vitro study. International Journal of Dental Materials, 2(3), 75–81.
Author Biographies

Khwaja Moinuddin MD, Sri Balaji Dental College

Senior Lecturer, Department of Conservative Dentistry and Endodontics, Sri Balaji Dental College.

Nagamaheshwari X, Army College of Dental Sciences

Senior Lecturer, Department of Conservative Dentistry and Endodontics, Army College of Dental Sciences.

Uday Kumar P, Army College of Dental Sciences

Senior lecturer, Department of Conservative Dentistry and Endodontics, Army College of Dental Sciences.

Shekar K, Sri Sai Dental College & Hospital

Proffessor & Head, Department of Conservative Dentistry and Endodontics, Sri Sai College of Dental Surgery

Mamta Kaushik, Army College of Dental Sciences

Professor & Head, Department of Conservative Dentistry and Endodontics, Army College of Dental Sciences.


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