Comparison of the marginal adaptation of direct and indirect composite inlay restorations with optical coherence tomography

Abstract

Objective The purpose of the study was to use the photonic imaging modality of optical coherence tomography (OCT) to compare the marginal adaptation of composite inlays fabricated by direct and indirect techniques.Material and Methods Class II cavities were prepared on 34 extracted human molar teeth. The cavities were randomly divided into two groups according to the inlay fabrication technique. The first group was directly restored on cavities with a composite (Esthet X HD, Dentsply, Germany) after isolating. The second group was indirectly restored with the same composite material. Marginal adaptations were scanned before cementation with an invisible infrared light beam of OCT (Thorlabs), allowing measurement in 200 µm intervals. Restorations were cemented with a self-adhesive cement resin (SmartCem2, Dentsply), and then marginal adaptations were again measured with OCT. Mean values were statistically compared by using independent-samples t-test and paired samples t-test (p<0.05), before and after cementation.Results Direct inlays presented statistically smaller marginal discrepancy values than indirect inlays, before (p=0.00001442) and after (p=0.00001466) cementation. Marginal discrepancy values were increased for all restorations after cementation (p=0.00008839, p=0.000000952 for direct and indirect inlays, respectively). The mean marginal discrepancy value of the direct group increased from 56.88±20.04 µm to 91.88±31.7 µm, whereas the indirect group increased from 107.54±35.63 µm to 170.29±54.83 µm. Different techniques are available to detect marginal adaptation of restorations, but the OCT system can give quantitative information about resin cement thickness and its interaction between tooth and restoration in a nondestructive manner.Conclusions Direct inlays presented smaller marginal discrepancy than indirect inlays. The marginal discrepancy values were increased for all restorations that refer to cement thickness after cementation.

Evaluation of adaptation of ceramic inlays using optical coherence tomography and replica technique

“…The replica technique and OCT are reliable, reproducible, and noninvasive techniques used to determine in vivo and in vitro adaptation of restorations to tooth surface without causing damage. 14,18,20,23,33,35 Thus in this study replica and OCT techniques were used. Previous studies had proved the facility of OCT to investigate adaptation of restorations without cutting the specimens.…”

“…Among nondestructive techniques, OCT has been used previously to evaluate the internal adaptations of composite restorations. 18,33,35 Internal adaptations of metal-ceramic and all-ceramic veneers were evaluated in a previous study, 38 but to our knowledge, internal adaptation of ceramic inlays has not been evaluated in the literature. In our study, OCT was used to measure the internal adaptation values of ceramic inlays.…”

“…36 The OCT systems that have ≥1260 nm wavelengths penetrate more into tissue. 18 These OCT systems were used in studies to evaluate the whole image of the fixed partial denture as well as qualitatively evaluate root canal or periodontal pocket. 30,38 Marginal and internal adaptations were evaluated in previous studies with lower wavelengths either qualitatively or quantitatively to obtain in-depth images.…”

“…OCT measurements of marginal adaptations of ceramic inlays were performed as described in a previous study using the Thorlabs OCT system, 18 which took spectral domain OCT images with 930-nm wavelengths. 39 The 100-nm-broad diode allowed for low speckle noise imaging.…”

“…17,18,[27][28][29]33,34,35,36,37,38 However, according to our knowledge, few studies exist in the literature related to the investigation of the adaptation of ceramic restorations to tooth structures using OCT. We quantitatively evaluated the marginal and internal adaptations of ceramic inlay restorations using OCT and compared the results with those of the silicone replica technique. Thus, the objectives of the study were to compare the OCT and replica techniques to assess marginal and internal fit and to investigate the marginal and internal adaptation of ceramic inlays.…”