The Effect of Various Restorative Materials on the Microhardness of Reparative Dentin

Abstract

This study showed a statistically significant difference between the microhardness of reparative and primary dentin at both five-and eight-week intervals. Reparative dentin from occlusal trauma is harder than reparative dentin underlying a cavity preparation at the 99% level. No statistical difference was noted in the hardness of reparative dentin underlying different materials, but trends were observed.

Impact of chemical agents for surface treatments on microhardness and flexural strength of root dentin

“…Lower microhardness values were obtained by specimens exposed to chemical agents other than to deionized water. As microhardness is sensitive to the composition and surface changes of the tooth structure, 27 alterations in the structure of root dentin achieved by chemical agents can reduce the microhardness, as observed in the present and previous investigations. 19,20 In this study, although the dentin had already been exposed to irrigations with NaOCl and EDTA during biomechanical treatment of root canals, chemical surface treatments provided additional structural changes, thereby compromising the dentin microhardness.…”

The effect of two different calcium hydroxide combinations on root dentine microhardness

“…As microhardness is dependent on composition and surface structure (Moon & Davenport 1976, Panighi & G'Sell 1992, attention has focused on the relationship between dentine microhardness and the structural changes associated with pulpectomy and the application of materials within root canals (Craig et al 1959, Fusayama & Maeda 1969, Cox et al 1980 Rotstein et al 1999, Saleh & Ettman 1999, Cruz-Filho et al 2001. A reduction in hardness of treated tooth tissue indicates dissolution and degradation (Craig et al 1959, Saleh & Ettman 1999.…”

The relationship between dentin microhardness and tubule density

“…Craig et al (3) reported Knoop hardness numbers (KHN) of dentin that ranged from 35 to 83 while Inisayama et al (4) reported a range of 20-70 KHN. 'Fhis wide variation is disturbing to those tryitig to tneasure ehanges in microhardness befbre atid after experimental procedures (1,12). Craig et al (3) suggested that dentin microhardness tnight be correlated with tubule density in view of the faet that dentin hardness deereased as measuremetits were tnade closer to the pulp.…”

“…Numerous invesligators have tneasurrd the hardness of dentin (1). Several investigators have reported that detitin tnierohardtiess varies iti different parts of a given tooth (3,4,13).…”