Influence of material and surface treatment on composite repair shear bond strength

Abstract

Objectives:The aim of this study is to investigate the influence of the composite material and surface treatment to the bond strength when repairing an aged composite surface with new composite.Materials and Methods:One hundred and sixty resin blocks of methacrylate composite and silorane composite prepared and aged in artificial saliva for 6 months. Specimens treated either with a diamond bur (DB) or air abrasion (AA), conditioned with orthophosphoric acid (OA) or sodium hypochloride (SH) and repaired with methacrylate or silorane composite using the corresponding adhesive system. Repaired composites underwent thermocycling fatigue (×5000), and bond strength was measured at shear.Results:Methacrylate achieved the highest bond strengths as repair material, in all combinations (26.54-55.56 MPa). Silorane only reached 8.12 MPa when repairing silorane treated with DB and OA. For all other treatment combinations repairing with silorane led to pretest failures. The most susceptible to repair composites/surface treatment combination is when repairing methacrylate treated with AA and SH and methacrylate composite (55.56 MPa).Conclusions:Silorane composites are not suitable to be used when repairing an old composite restoration. The repair material is the most critical factor, while aged surface treatment has only a minor influence to the shear bond strength.

Which surface treatment improves the long-term repair bond strength of aged methacrylate-based composite resin restorations? A systematic review and network meta-analysis

“…The sample sizes varied between 5 [43] to 61[30] in each study. The aging methods included liquid storage (water [3, 9, 27, 44, 45] and saliva [46]), thermocycling [20, 22-25, 29, 31, 32, 42, 47], or a combination of the two [21, 26, 28, 30, 43, 48]. Seven studies [22-25, 30, 43, 46] provided micro-tensile bond strength, four [3, 9, 44, 47] indicated micro-shear bond strength, ten [20, 21, 26-29, 31, 32, 42, 48] gave shear bond strength, and only one [45] evaluated tensile bond strength.…”

“…The surface treatment protocols performed on old composite resins also play a significant role in determining the durability of the repair bond. Invitro research findings had also utilized a variety of surface treatment methods, such as roughening with abrasive papers [20][21][22][23], diamond burs [24][25][26], Al 2 O 3 particles [3,22,27], silica coated particles [28][29][30], and lasers [31,32] as mechanical; and numerous bonding mechanisms, adhesives, and salinization as chemical surface treatments [3,22,23,27], solely or in combination to overcome the bonding obstacles. The main objective of such surface modifications is to produce a strong bond through the micromechanical interlocking between fresh and old composite resins.…”

The influence of different surface treatment protocols and bonding agents on the repair microtensile bond strength of six-month’ aged composite: An in vitro study

“…Eight microhybrid cylinder-shaped composite blocks (Opallis, shade A2) were fabricated using a Teflon mold (8mm diameter x 4 mm height) [12,18,[20][21][22], such that each 2-mm-thick increment was separately cured for 40 seconds using Elipar LC curing unit Coltène/Whaledent AG, Altstätten, Swizerland (3M, USA ) with an intensity of 600 mW/cm 2 [7,11,12,18,[20][21][22]. All blocks were stored in artificial saliva for six months [23].…”

Siloranes–Suitability of a Novel Adhesive for Orthodontic Bracket Bonding

“…Marginal adaption and micropermeability are controversially discussed in the existing literature, suggesting no advantage for siloranes [12,13]. Shear bond strengths tend to be lower, both to dentin [14] and enamel [15], as well as to aged methacrylate blocks simulating the repair of older restorations [16].…”