Clinical evaluation of nonvital tooth whitening and composite resin restorations: five-year results

The purpose of this study was to evaluate the efficacy of nonvital bleaching and clinical performance of direct composite restorations when used to reconstruct multisurface restorations on endodontically bleached teeth. Twenty-one patients 18 years or older were included in this clinical trial. Twenty-six endo-bleached maxillary and mandibular teeth were restored using a microhybrid composite resin. A Vita shade guide arranged by value order was used to record the shade for each patient. Temporary or existing restorations were removed along with 1 mm of gutta-percha below the cementoenamel junction and a resin-modified glass ionomer barrier was placed. Bleaching treatment was performed in the office and at home. Two weeks after the completion of bleaching, teeth were restored using a combination of a filled adhesive system and microhybrid composite resin. All but one restoration was evaluated every 12 months during a 5-year period using modified United States Public Health Service criteria by two independent evaluators. No failures were reported and alpha scores were recorded for all parameters except color stability (Alpha: 10; Bravo: 14; Charlie: 1). ANOVA showed a significant shade change between baseline (mean = 14.13) and 2 weeks (mean = 1.6), 2 years (mean = 2.8), and 5 years (mean = 3.4), P < .0001. A post hoc test showed a significant shade change between a 2week and 5-year follow up (P = .001). Shade rebound was reported for 15 out of 25 nonvital teeth, but was limited to a maximum of 6 shades; direct anterior composite restorations demonstrated outstanding clinical performance after 5 years.