Effect of Silane Coupling on the Clinical Performance of Repaired Composite

Effect of Silane Coupling Treatment on the Clinical Performance of Direct Repaired Resin-based Composite: A Randomized Controlled Trial.

Research Problem : Advances in adhesive technologies have introduced several surface treatment concepts that enable the clinician to adhere resin-based composite restorations onto new composite materials. The service life of faulty direct composite restorations can be prolonged by composite repair wherein durable adhesion between old and new resin-based composite materials is established.

Objectives : A randomized controlled clinical trial was designed to apply the latest results of evidence-based in vitro studies regarding resin-based repair protocol. The study aimed to assess the effect of adding silane coupling agent as a separate step on the clinical performance of repaired composite restorations and compare the results with those of using the usual etch and bond protocol.

Materials and Methods : 45 patients were recruited for this study from patients attending the restorative dentistry clinics for postgraduate students, Jordan University of Science and Technology. Each patient had at least two defected posterior composite restorations that are indicated for repair. With this selection, 116 restorations with localized anatomical deficiencies and/or secondary caries were randomly assigned into three groups according to the type of surface treatment each tooth will receive before the application of the new composite material (Filtek Z250,3M,USA). The teeth in the control group (n = 45): were treated with 37% phosphoric acid etching and conventional one step adhesive (Single Bond,3M,USA). In the Silane-Adhesive group (n = 26): teeth were treated with acid etching and silane coupling agent application (Bis-silane) prior to adhesive bond (Adper single bond). In the Sandblast-Silane-Adhesive group (n = 45): teeth were treated with intra-oral sandblasting and silane coupling agent application (Bis-silane) prior to (Adper Single Bond). The reason of repair, age of old restorations and the location of the restoration-repair interfaces were recorded for every failed restorations. Two examiners followed-up and evaluated the restoration quality after an average of 6 months using modified USPHS criteria. The results of clinical performance were assessed using Chi-square test.

Inclusion Criteria:

• Deciduous tooth
• Sustained dentin hypersensitivity
• Irreversible pulpitis , necrotic, or inadequately-treated endodontic teeth
• Grossly defective composite restorations that were indicated for replacement.
• Teeth with compromised periodontal status.
• Patients with poor oral hygiene

Exclusion Criteria:

• Patients older than 18 years.
• Asymptomatic restored premolars or molars.
• Vital or endodontically treated teeth
• Patients with localized, marginal, anatomical deficiencies and/or carious lesions adjacent to composite restorations or esthetically unpleasant restorations.
• Teeth with marginal gingivitis but healthy periodontium.
• Tooth in normal occlusion with antagonist and at least one adjacent tooth.