Removal of temporary cements following an immediate dentin hybridization approach: a comparison of mechanical and chemical methods for substrate cleaning

Abstract

This study evaluated the microshear bond strength (SBS) of a composite resin cement to a pre-hybridized dentinal substrate exposed to two kinds of temporary materials; the influence of different cleaning techniques was investigated. Dentinal surfaces were conditioned with an etch-and-rinse adhesive system to obtain an immediately-sealed (IDS) layer. Each surface was divided into quadrants and covered (1) with an eugenol-free (NE_Group) or (2) with a resin-based provisional agent (CL_Group). After storage, the temporary cement was removed by using one of the following methods: (1) Hand-scaler [S]; (2) Alumina air-abrasion [SB]; (3) Glycine-powder air-abrasion [Gly]; (4) D-Limonene chemical solvent [Or]. A new IDS layer was then created; polyethylene tubes were placed on dentin surfaces and filled with a dual-cure resin cement. A universal testing machine was used for the SBS tests; conditioned surfaces were analyzed at SEM. Means and SD were calculated; a two-way ANOVA (a: 0.05) was performed to detect significant differences among groups. For NE groups, mean SBS values (MPa) were: 21.6 ± 6.6 [NE_NoT]; 20.7 ± 4.5 [NE_Or]; 20.1 ± 6.6 [NE_SB]; 19.1 ± 5.3 [NE_S]; 17.8 ± 2.2 [NE_Gly]. No significant differences were found among tested treatments within NE (p: 0.5493). For CL groups, mean SBS values (MPa) ranged from 15.8 ± 2.8 (CL_S50) to 19.4 ± 2.9 (CL_Gly). Cleaning of the substrate with glycine air-abrasion statistically improved SBS values with respect to aluminum-oxide (CL_SB: 15.8 ± 2.8) or scaling (CL_S: 16.0 ± 2.4). The application of the IDS technique was effective for preservation of freshly-cut dentin from adverse effects of temporary materials. Glycine air-abrasion is suggested when a temporary resin cement is adopted.

Immediate Dentin Sealing: A Literature Review

“… Nikaido et al 2018 17 Review - - Coating materials have the potential to reinforce sound tooth,leading to the maximum preservation of tooth structures. Augusti et al 2018 47 In vitro Bond strength Investigated the influence of different cleaning techniques (Hand-scaler/Alumina air-abrasion/Glycine powder air-abrasion/D-Limonene chemical solvent) upon microshear bond strength of a composite resin cement (Nexus Universal adhesive luting cement) to a pre-hybridized dentinal substrate (Optibond FL) exposed to two different temporary materials (TempBond NE/TempBond Clear) IDS protected freshly-cut dentin from the adverse effects of temporary materials. Glycine air-abrasion was suggested when a temporary resin cement is adopted.…”

“…Application of a separating medium combined with spot bonding seems to serve the above-mentioned requirements. Moreover, resin-based temporary cements should be avoided, 47 unless isolation using a water-soluble gel has been applied beforehand. 34…”

Influence of resin-coating on bond strength of resin cements to dentin and CAD/CAM resin block in single-visit and multiple-visit treatment

“…Several researches have evaluated the effect of temporization on dentin with/without resin-coating 9,24,25) . It was revealed that the removal of non-eugenol temporary cement with only the excavator was enough to avoid the reduction in the final bond strength 24,25) . However, cement remnants were observed in the noncoated and resin-coated groups (see Fig.…”

Substantial in-vitro and emerging clinical evidence supporting immediate dentin sealing

“…The selection of provisional cement has been shown to exert a significant effect on the bond strength of the final restorations. The use of calcium hydroxide and zinc oxide eugenol-free cement has been shown to have little or no effect on bond strength of final restorations as compared to zinc oxide-eugenol and resin-based provisional cements [ [76] , [77] , [78] ].…”

“…As provisional cement potentially contaminates the surface of the first layer of the resin adhesive resulting in compromised bond strength, a thorough cleaning of provisional luting cements before final cementation is essential [ [79] , [80] , [81] , [82] ]. Different provisional cement cleaning methods have been suggested which can be categorized as mechanical [ [76] , [77] , [78] , [79] , [80] , [82] , [83] , [84] , [85] , [86] ] chemical [ 78 , 80 , 87 ] and laser [ 80 ] ( Table 4 ). It is important that the cleaning method being used removes all remnants of provisional cement from the surface of the first resin adhesive layer to allow optimal bonding with the second resin adhesive layer that is applied during the final cementation.…”