IADR Abstract Archives
Effects of Desensitizers on the Microhardness of Enamel and Dentin
Objectives: To evaluate the effect of desensitizing agents with different contents on human enamel and dentin surfaces.
Methods: Seventy enamel and dentin surfaces were obtained from the buccal surfaces of extracted human non-carious incisors. The samples were embedded in acrylic resin and the surfaces were ground flat with SiC papers (600, 1000, 2500, 4000 grits), until the enamel and dentin surfaces appear together.
Teeth were randomly divided in seven groups according to the desensitizing agents applied (n=10):
(1) Hydroxyapatite(Teethmate Desensitizer,Kuraray),
(2) Hydroxyapatite&Potassiumnitrate(ExSense,Cavex),
(3) Potassiumnitrate&Fluoride(UltraEZ,Ultradent),
(4) Caseinphosphopeptide-Amorphouscalciumphosphate(CPP-ACP)(ToothMousse,GC),
(5) Arginine&Sodiumfluoride(Elmex Sensitive Professional,GABA/Colgate-Palmolive),
(6) Arginine&Calciumcarbonate(Sensitive Pro-Relief Desensitizing Paste,Colgate),
(7) Glutaraldehyde(Gluma Comfort Bond+Desensitizer,Heraeus Kulzer).
Microhardness measurements of the enamel and dentin surfaces were determined before and after application of desensitizing agents using a microhardness tester (HMV Microhardness Tester,Shimadzu) with a Vickers diamond under a load of 980.7mN/15s. Five indentations were made on each enamel and dentin surfaces and the average values were calculated. Additionally, the percentage of microhardness change was calculated. The data were analyzed with Wilcoxon Sign and Kruskal-Wallis tests (p<0.05).
Results: Kruskal-Wallis test revealed no differences for initial microhardness values of both enamel and dentin surfaces (p>0.05). Application of hydroxyapatite & potassium nitrate, potassium nitrate & fluoride and glutaraldehyde containing desensitizers significantly decreased microhardness of enamel surfaces. Only, arginine & calcium carbonate containing desensitizer improved the microhardness of enamel surface (1.75%). Microhardness values of dentin surfaces were decreased by hydroxyapatite & potassium nitrate, arginine & sodium fluoride and glutaraldehyde containing desensitizers, while increased by CPP-ACP paste (p<0.05). The microhardness recovery of dentin surfaces occurred after application of potassium nitrate & fluoride (5.02%) and CPP-ACP paste (2.68%).
Conclusions: Desensitizers could provide comparable microhardness characteristics both for enamel and dentin surfaces.
Methods: Seventy enamel and dentin surfaces were obtained from the buccal surfaces of extracted human non-carious incisors. The samples were embedded in acrylic resin and the surfaces were ground flat with SiC papers (600, 1000, 2500, 4000 grits), until the enamel and dentin surfaces appear together.
Teeth were randomly divided in seven groups according to the desensitizing agents applied (n=10):
(1) Hydroxyapatite(Teethmate Desensitizer,Kuraray),
(2) Hydroxyapatite&Potassiumnitrate(ExSense,Cavex),
(3) Potassiumnitrate&Fluoride(UltraEZ,Ultradent),
(4) Caseinphosphopeptide-Amorphouscalciumphosphate(CPP-ACP)(ToothMousse,GC),
(5) Arginine&Sodiumfluoride(Elmex Sensitive Professional,GABA/Colgate-Palmolive),
(6) Arginine&Calciumcarbonate(Sensitive Pro-Relief Desensitizing Paste,Colgate),
(7) Glutaraldehyde(Gluma Comfort Bond+Desensitizer,Heraeus Kulzer).
Microhardness measurements of the enamel and dentin surfaces were determined before and after application of desensitizing agents using a microhardness tester (HMV Microhardness Tester,Shimadzu) with a Vickers diamond under a load of 980.7mN/15s. Five indentations were made on each enamel and dentin surfaces and the average values were calculated. Additionally, the percentage of microhardness change was calculated. The data were analyzed with Wilcoxon Sign and Kruskal-Wallis tests (p<0.05).
Results: Kruskal-Wallis test revealed no differences for initial microhardness values of both enamel and dentin surfaces (p>0.05). Application of hydroxyapatite & potassium nitrate, potassium nitrate & fluoride and glutaraldehyde containing desensitizers significantly decreased microhardness of enamel surfaces. Only, arginine & calcium carbonate containing desensitizer improved the microhardness of enamel surface (1.75%). Microhardness values of dentin surfaces were decreased by hydroxyapatite & potassium nitrate, arginine & sodium fluoride and glutaraldehyde containing desensitizers, while increased by CPP-ACP paste (p<0.05). The microhardness recovery of dentin surfaces occurred after application of potassium nitrate & fluoride (5.02%) and CPP-ACP paste (2.68%).
Conclusions: Desensitizers could provide comparable microhardness characteristics both for enamel and dentin surfaces.