Objectives: This clinical study was conducted to evaluate the efficiency of nanohydroxyapatite (n-HAp) in reducing dentin hypersensitivity individually or combined with fluoride. Materials and methods: Forty hypersensitive teeth from 10 patients with hypersensitive symptoms were treated using hydroxyapatite nanoparticles (nHAp) gel at different concentrations/ sodium fluoride (NaF) containing according to four treatment groups: Group 1; 15% nHAp + 1% NaF, Group 2; 15% nHAp, Group 3; 25% nHAp+ 1% NaF, Group 4; 25% nHAp. The initial sensitivity levels were recorded using a verbal rating scale (VRS) and visual analogue scale (VAS) at the baseline visit. The responses were evaluated at 0, 1 day, 1, 2 and 4 weeks respectively for all groups. Results: There was a high statistical significant differences between pain scores before and after treatment for all treated groups. There was statistically significantly high difference between 25% nHAp and the other groups, as they need 4 applications for complete relief while 25% nHAp needs only 3 applications. Conclusion: Nanohydroxyapatite with 25% concentration was the most effective in alleviating the hypersensitivity symptoms.

Objectives:-This study was conducted to evaluate the clinical and laboratory effect of three different treatment modalities in management of dentin hypersensitivity. Materials and methods: one hundred-twenty samples were used in the study procedures, for dentin permeability test and Scanning Electron Microscopic examination (SEM). The samples were randomly divided into two groups Group A 1 , totally removed smear layer Group A 2 , partially removed smear layer. Each group was further subdivided into four subgroups according to the treatment agent applied: ammonium hexafluorosilicate (SiF) gel, propolis extract, Curodont D'senz and the control group that were left untreated. One hundred and five (105) hypersensitive teeth were enrolled for this study. The subjective assessment of dentin hypersensitivity was done before application of the agent (baseline) then immediate, 1 week, 2 weeks, 4 weeks and 3 months respectively. Patients were asked to rate their perception to tactile, air and cold stimuli by using Verbal Rating Scale (VRS) and Visual Analogue Scale (VAS). Results: Permeability results revealed that there were high statistical significant difference between the study groups with lowest statistically significant mean depth of dye penetration values were found with propolis treated samples. The results of the clinical study revealed that there was high significant difference between pain scores before and after treatment for all tested groups. Conclusion: Propolis extract, Curodont D'senz and SiF gel were effective in reducing dentin permeability, occluding dentinal tubules and alleviating the hypersensitivity symptoms, with propolis extract paste being the most effective within 1 to 2 weeks and sustained up to 3 months.

Objectives: This study was conducted to evaluate the remineralization potential of grape seed extract versus amorphous calcium phosphate nanoparticles on sound and caries affected dentin. Materials and methods: Grape seed extract powder (GSE) was added to Clearfil SE primer with a concentration of 0.5 wt% to obtain primer + GSE while nanoparticles of amorphous calcium phosphate (NACP) were incorporated into the Clearfil SE adhesive at mass fractions of 20% to obtain adhesive + NACP. Class V cavity preparation was prepared on the anterior teeth of fifteen white rabbits. Rabbits were divided into three main groups according to the type of material used Group A (primer + GSE) Group B (adhesive + NACP), Group C (sodium fluoride NAF as positive control). Each group was subdivided into two subgroups according to type of substrate in which right side was act as sound dentin while left side was act as artificial caries affected dentin. After 10 days the dentin was examined using EDX analysis to determine amount of calcium and phosphorus in each sample. Results: There was no statistically significant difference between mineral content of different materials compared with positive control group for both sound and caries affected dentin. Conclusion:-Grape seed extract and nano amorphous calcium phosphate can produce remineralization of sound and caries affected dentin as sodium fluoride.

Objectives: This study was conducted to evaluate the effect of incorporating Nanocalcium phosphate (NCP) particles into Biodentine™ on pulpal tissue response as a direct pulp capping material (entire tooth culture model). Materials and methods: -A total of forty freshly human premolar teeth extracted for orthodontic reasons were used. After cavity preparation and mechanical pulp exposure, the teeth were divided into 2 main groups (20 teeth each) according to the capping material used; where group (M1) refers to pulps capped with Biodentine™, and group (M2) refers to pulps capped with Biodentine incorporated with NCP. Each group was further subdivided into two subgroups according to the culture period; where subgroup (P1) refers to teeth cultured for 14 days, and subgroup (P2) refers to teeth cultured for 28 days. At the end of each culture period, the teeth were histologically examined to assess the dentine bridge thickness of each group after 14 and 28 days. Moreover, elemental analysis of Calcium and Phosphorous ions in the dentine bridge was performed using SEM-EDX. Results: Direct pulp capping with Biodentine incorporated with NCP showed thicker dentine bridge when compared to Biodentine™ alone. There is a positive correlation between the weight % of Calcium and Phosphorous ions in the dentine bridge below both capping materials and the dentine bridge thickness. Conclusion: Biodentine incorporated with NCP could be a good candidate for pulp capping in the future.

Purpose:The study was established to compare the remineralization effect of natural agents versus bioadhesive polymers with or without PH cycling using a microhardness test. Materials and Methods: Forty extracted premolars were used. The roots of the teeth were removed, then the crowns of teeth were cut in mesiodistal direction to expose the labial and lingual portion using a diamond disc so that 80 specimens were obtained. Each tooth-half was fixed with superglue on the custom made acrylic block. The enamel surfaces were polished to produce flat enamel surfaces. 80 specimens were divided into four groups (A) according to the remineralizing agent used. Group A1 for eggshell nanoparticles, Group A2 for clove extract, and Group A3 for carbopol, and Group A4 for carboxymethyl cellulose (20 each). Each group was subdivided into two subgroups (10 each) according to PH cycling either with (B1) or without (B2). Then, the specimens were examined before and after demineralization and after treatment agent with Digital Display Vicker Microhardness Tester. Results: The results showed that the highest microhardness mean values were found with eggshell nanoparticles followed by carbopol, and then carboxymethyle cellulose then clove extract. Conclusion: Natural materials have remineralizing potentials and could successfully replace synthetic products.