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Ronald Perry

Publications and source records attributed to Ronald Perry.

4 recordsLinked to original sources
PubMed2003

Microleakage of resin-based liner materials and condensable composites using filled and unfilled adhesives.

PURPOSE: To evaluate the efficacy of differing resin based liner materials in reducing microleakage. METHODS: 80 freshly extracted caries-free human premolars and molars were used. MO/DO Class II standardized preparations were performed with the gingival margin placed 1 mm above the CEJ. Teeth were randomly divided into two groups; each one was divided into four subgroups (A-B-C-D for Group 1 and E-F-G-H for Group 2). Each prepared tooth was etched with 32% H3PO4 (Uni Etch); in Group 1, one coat of One Step and in Group 2, two coats and two cures of Prime & Bond NT adhesives were applied. In each group 1 mm layer of three different liners was used: A2 Heliomolar RO for A and E; A2 Heliomolar Flow for B and F; A2 Bisfil 2B for C and G. No liner was used for D and H subgroups. Teeth were then restored using 2 mm increments of Pyramid A2 Dentin and A1 Enamel and cured with a VIP curing light. Teeth were thermocycled x500 between 5 degrees C and 55 degrees C with a dwell of 30 seconds and then placed in a 0.5% methylene blue dye solution for 24 hours at 37 degrees C. Samples were sectioned longitudinally and evaluated for microleakage at the gingival margin under a stereomicroscope at x20 magnification. Dye penetration was scored using an Ordinal Scoring System where 0= no penetration; 1= enamel penetration; and 2= dentin penetration. RESULTS: A Chi Square Test revealed a statistically significant difference between Group 1 and Groups 2 (P < 0.001). Group 1 yielded the most microleakage. No statistically significant difference was noted between the subgroups of each group; a statistically significant difference of B and D vs. E and H (P < 0.01 > 0.001) and B vs. G and D (P < 0.05 > 0.01) was also noted. The dentin bonding agent in Group 2 contributed to a reduction of microleakage when compared to Group 1.

Acid Etching, Dental↗
PubMed2002

Direct composite resins: an update.

Esthetic restorative materials require a bonding procedure to achieve durability and reliability. To accomplish this, the bonding system and restorative material must be biocompatible and bond well to both dentin and enamel. The direct restorative must have sufficient strength to resist masticatory forces as well as mechanical properties close to those of natural tooth structure. These materials should be resistant to degradation in the oral cavity and easy to use. This article reviews the published literature on direct composite restorative materials.

Ceramics↗