Cleaning Zirconia Surface Prior To Bonding: A Comparative Study of Different Methods and Solutions.

PURPOSE: To evaluate resin cement bond strength after removal of salivary contamination from a zirconia surface using different cleaning solutions and air-borne particle abrasion. MATERIALS AND METHODS: One-hundred and twenty zirconia specimens (KATANA STML, Noritake) were prepared and divided into 12 groups (n = 10). Groups were subjected to a notched-edge shear bond strength test (ISO 29022) to analyze the bonding efficiency of a resin cement (Panavia V5, Kuraray Noritake Dental Inc.) before and after contamination with saliva. Group 1 (control) was prepared and cemented without salivary contamination. Group 2 was coated with ceramic primer (Clearfil Ceramic Primer Plus, Kuraray Noritake Dental Inc.) then subjected to salivary contamination then tested. Group 3 was contaminated, cleaned by air-borne particle abrasion, ceramic primer and resin cement applied, and tested. Groups 4 to 12 were contaminated, and then different cleaning solutions (water, 4.5% hydrofluoric acid, 35% phosphoric acid, Ivoclean, KATANA cleaner, Zirclean, sodium hypochlorite 4%, and 7.5%) were used to decontaminate the zirconia surface, followed by ceramic primer, resin cement application, and tested. One-way ANOVA and Tukey post-hoc analysis was used to analyze the data. RESULTS: One-way ANOVA showed statistical differences among cleaning procedures (p < 0.001, F = 13.48). Air-borne particle abrasion was the only group which provided a bond strength (21 ± 2.8 MPa) that was not statistically different than the control group in which no contamination occurred (25.3 ± 3.3 MPa) (p = 0.247). The use of hydrofluoric acid and zirconia cleaning solutions resulted in bond strengths values which were not statistically different from each other (17.5-19.1 MPa). CONCLUSION: Air-borne particle, zirconia cleaning solutions and hydrofluoric acid are feasible to decontaminate the zirconia surface from saliva prior to bonding the restoration.

Optical properties of bisacryl-, composite-, ceramic- resin restorative materials: An aging simulation study.

OBJECTIVE: Compare optical properties of a bisacryl-, composite-, and ceramic-resin restorative materials pre and post artificial aging. METHODS: Bisacryl-resin (LuxaCrown [LC], DMG), resin-composite (Filtek Supreme Ultra, [Filtek SU] 3M ESPE), and ceramic-resin (Enamic, VITA Zahnfabrik) specimens were prepared. The L*, C*ab , and hab values were measured pre and post artificial aging to determine color stability (CIEDE2000) and changes in contrast ratio (CR), transmittance block, and relative translucency parameter. The datasets were analyzed using 2-way ANOVA followed by pairwise comparisons. RESULTS: Color difference data showed a significant interaction between materials and treatments [F(6:60) = 375.04, P < .0001] with Enamic being most color stable material and coffee having most effect on color stability. CR data showed a significant interaction between materials and treatments [F(6:60) = 4.12, P = .0016]. LC showing most change in CR values with coffee treatment. Change in transmittance blocked by Filtek SU and LC was greater for coffee treatment than that by each of the other treatments (P < .0001). Filtek SU and LC, coffee produced a greater decrease in relative translucency than that each of the other treatments (P < .0001). CONCLUSIONS: Resin-based materials demonstrate optical properties that encourage their use for direct/indirect restorative options. Color stability and translucency of these materials are proportionally related. CLINICAL SIGNIFICANCE: Understanding the optical properties of resin-based materials provides help in material selection and provides insight into clinical performance and esthetic longevity. The optical stability of certain bisacryl-resin is better than what was previously determined for these restorative materials.