Detecting demineralisation adjacent to veneer restorations using Quantitative Light- Induced Fluorescence

Purpose: 1. To observe the appearance of porcelain veneers under QLF conditions 2. To determine if QLF could detect and monitor longitudinally, demineralisation around porcelain veneer restorations. Methods: Thirteen cleaned bovine teeth devoid of cracks, stains and enamel defects were selected. The roots were removed using a diamond disc. The teeth were gently pumiced (SS White, UK) and then abraded with medium and fine "wet and dry? paper. Laboratory made porcelain veneers measuring approximately 3mm x 3mm were made and treated with silane primer (Kerr Corporation, U.S.A) and then bonded to etched tooth surfaces (37% orthophosphoric acid) according to the manufacturer?s instructions using the Optibond and Nexus 2 universal luting systems (Kerr Corporation, U.S.A). The margins were examined for excess bonding material with QLF and cleaned using medium and fine Soflex discs (3M ESPE). Windows measuring approximately 2mm x 3mm were created superior and inferior to the veneer margins using clear acid resistant varnish (Max Factor, Proctor and Gamble, UK). After leaving to dry for 24 hours, the teeth were mounted on glass rods attached to "sterlin? type pot lids. Baseline QLF images were taken and the teeth were immersed in 30ml of acid buffer demineralising solution. QLF images were captured at 3, 6, 9, 12, 24, 36, 48 and 60 hours. All the images were analysed using the inner patch QLF technique. Results: Porcelain veneers exhibited reduced fluorescence when compared with enamel under QLF. Demineralisation was observed adjacent to all the restorations. There was a significant treatment effect between the baseline images and the 60 hour demineralised images (paired t-test p<0.05). There was a significant correlation between the time of exposure and the degree of demineralisation as measured by ΔF (Pearson coefficient =0.89, r2 =0.79). Clinical Significance: QLF may serve as an adjunct to the visual, chairside diagnosis and management of dental caries around veneer restorations with particular emphasis on preventive regimes. © 2011 Nova Science Publishers, Inc