Method and Materials: Thirty-two freshly extracted caries-free human third molars were used. A wide mesio-occlusal-distal (MOD) cavity was prepared in each third molar, with the occlusal dimension being approximately twothirds of the intercuspal dimension, and the cervical limit of one proximal box was stopped 1 mm below and the other 1 mm above the cementoenamel junction. The cavities were filled with a methacrylate-based nanohybrid composite (Grandio, VoCo) and a silorane-based microhybrid composite (Filtek Silorane, 3M ESPE). All samples were subjected to 1000 thermal cycles of 5°C/55°C in water with a 30-second dwell time and, after the procedure, the teeth were immersed in a 0.5% basic fuchsin dye at 23°C for 24 hours. Sectioned samples were examined under a stereomicroscope (Leica MZ12, Leica Microsystems), and microleakage scores were statistically analyzed using the Kruskal-Wallis and the Mann-Whitney U tests. Clinical RelevanceThis in vitro study showed that the Silorane-based microhybrid resin composite system had no microleakage for wide Class II MOD restorations with oblique and vertical layering techniques.

ObjectivesThis study aimed to evaluate the color stability of bulk-fill and nanohybrid resin-based composites polished with 3 different, multistep, aluminum-oxide impregnated finishing and polishing disks.Materials and MethodsDisk-shaped specimens (8 mm in diameter and 4 mm in thickness) were light-cured between two glass slabs using one nanohybid bulk-fill (Tetric EvoCeram, Ivoclar Vivadent), one micro-hybrid bulk-fill (Quixfil, Dentsply), and two nanohybrid incremental-fill (Filtek Ultimate, 3M ESPE; Herculite XRV Ultra, Kerr) resin-based composites, and aged by thermocycling (between 5 - 55℃, 3,000 cycles). Then, they were divided into subgroups according to the polishing procedure as SwissFlex (Coltène/Whaledent), Optidisc (Kerr), and Praxis TDV (TDV Dental) (n = 12 per subgroup). One surface of each specimen was left unpolished. All specimens were immersed in coffee solution at 37℃. The color differences (ΔE) were measured after 1 and 7 days of storage using a colorimeter based on CIE Lab system. The data were analyzed by univariate ANOVA, Mann-Whitney U test, and Friedmann tests (α = 0.05).ResultsUnivariate ANOVA detected significant interactions between polishing procedure and composite resin and polishing procedure and storage time (p < 0.05). Significant color changes were detected after 1 day storage in coffee solution (p < 0.05), except Quixfil/Optidisc which was color-stable after 7 days (p > 0.05). Polishing reduced the discoloration resistance of Tetric EvoCeram/SwissFlex, Tetric EvoCeram/Praxis TDV, Quixfil-SwissFlex, and all Herculite XRV Ultra groups after 7 days storage (p < 0.05).ConclusionsDiscoloration resistance of bulk-fill resin-based composites can be significantly affected by the polishing procedures.

BackgroundAlthough numerous studies have used digital intraoral imaging, only a few studies have used photo-optical methods for the diagnosis of caries. Moreover, several limitations exist in terms of observers (experience and specialty) and the caries lesion itself. Hence, the aims of this study were to evaluate the diagnostic capability of near-infrared light transillumination (NILT) and PSP-Bitewing radiographs and to compare the interobserver and intraobserver differences in addition to observers’ experience level to detect early interproximal caries lesions in vivo.MethodsA total of 52 untreated posterior teeth with and without varying degrees of early interproximal carious lesions were included. Bitewing radiographs using digital phosphor plates (PSP-Bitewing) and NILT were used to clarify the diagnosis. An oral and maxillofacial radiologist and a restorative dentistry consultant evaluated the images twice. A separate appointment for clinical validation and restoration was made. Kappa coefficients were calculated to assess both intraobserver and interobserver agreements for each evaluation method. Scores obtained from PSP-Bitewing and NILT were compared with the clinical validation via receiver operating characteristic (ROC) analysis.ResultsNo significant differences were found between PSP-Bitewing radiography and NILT for detecting early interproximal carious lesions with high average Az results. Both intraobserver and interobserver agreement values were relatively higher for NILT evaluation. The Az values increased at second evaluations for both caries detection methods.ConclusionsNILT examination has an appropriate sensitivity and diagnostic accuracy for detecting early interproximal caries lesions and can be considered as a method of choice for detecting caries without the use of ionizing radiation.

BackgroundThe aim of this study was to analyze the bond strength of aged resin based nanocomposites repaired with the same and bulk fill composites.Material and MethodsSeventy-two disc shaped resin composites consisted of three different nanocomposite resins (Filtek Ultimate/FU, Herculite XRV Ultra/HXRV, and Reflectys/R) were produced. After storing the samples for 8 weeks in distilled water, each material was combined with the same material or the bulk-fill composite resin system (Filtek Ultimate+Filtek Ultimate/Group-1; Filtek Ultimate+Tetric BF/Group-2; Herculite XRV+Herculite XRV/Group-3; Herculite XRV+Tetric BF/ Group-4; Reflectys+Reflectys/Group 5; Reflectys+Tetric BF/Group-6), for repair. Then specimens were subjected to shear bond strength testing(SBS), and the debonded surfaces were examined.ResultsThere was a significant difference among three materials(repaired with itself+bulk fill) for SBS testing values (p=0.001). FU and R were found to be similar, while HXRV was significantly different from them. A significant difference between group-1 and 2 (p=0.006) was detected, while there were no differences between group 3 and 4 (p= 0.142), and 5 and 6 (p=0.346). Among the six groups, repair SBS testing values with TBF were higher than repair with itself except for FU.ConclusionsThe bulk-fill repaired materials showed higher bond strength except for FU, which showed the highest SBS value when repaired with itself. An increased incidence of adhesive fracture was observed at low strengths. Key words:Resin-based composites, nanofillers, surface treatment, macro-shear, repair.

BackgroundAir-drying of etched and rinsed dentin surface may force the exposed collagen fibrils to collapse. Blot-drying is an alternative method to wipe the excess water from the dentin surface without compromising the monomer penetration. Contemporary total etch adhesives contain ethanol/water or acetone as solvent in which resin monomers are dissolved. Solvent type of the adhesive system has an important role in bonding to dentin. An adhesive containing tertiary butanol as an alternative solvent has been in the market. Purpose of this study is to determine the shear bond strengths of three total-etch adhesives with different solvents (acetone, ethanol or tertiary butanol) applied to air or blot dried moist dentin.MethodsSixty extracted non-carious human third molars were divided into three main groups according to solvent content of the adhesives [acetone based - One Step (OS, Bisco, IL, USA); ethanol/water based - Optibond Solo Plus (OB, Kerr, CA, USA); and tertiary butanol based - XP Bond (XP, Caulk/Dentsply, DE, USA)]. Each main group was divided into two groups according to drying methods (blot or air) (n = 10). Shear bond strengths (SBS) were measured. Data were analyzed by Student’s t test and Tukey HSD test (p < 0,05).ResultsXP showed highest SBS values in both drying methods applied (p < 0.05). Drying method did not influence the SBS in OS and OB (p > 0.05). XP-blot produced significantly higher SBS than XP-air (p < 0.05).ConclusionsTertiary butanol based adhesive showed higher bond strength values than ethanol or acetone based adhesives. Blot drying of dentin improved the bond strength values of tertiary butanol based adhesive. Further research is necessary to determine in vivo and in vitro performance of tertiary butanol based adhesives.

Objectives: To assess the in vitro diagnostic ability of CBCT images using seven different display types in the detection of recurrent caries. Methods: Our study comprised 128 extracted human premolar and molar teeth. 8 groups each containing 16 teeth were obtained as follows: (1) Black Class I (Occlusal) amalgam filling without caries; (2) Black Class I (Occlusal) composite filling without caries; (3) Black Class II (Proximal) amalgam filling without caries; (4) Black Class II (Proximal) composite filling without caries; (5) Black Class I (Occlusal) amalgam filling with caries; (6) Black Class I (Occlusal) composite filling with caries; (7) Black Class II (Proximal) amalgam filling with caries; and (8) Black Class II (Proximal) composite filling with caries. Teeth were imaged using 100 3 90 mm field of view at three different voxel sizes of a CBCT unit (Planmeca ProMax ® 3D ProFaceÔ; Planmeca, Helsinki, Finland). CBCT TIFF images were opened and viewed using custom-designed software for computers on different display types. Intraand interobserver agreements were calculated. The highest area under the receiver operating characteristic curve (Az) values for each image type, observer, reading and restoration were compared using z-tests against Az 5 0.5. The significance level was set at p 5 0.05. Results: We found poor and moderate agreements. In general, Az values were found when software and medical diagnostic monitor were utilized. For Observer 2, Az values were statistically significantly higher when software was used on medical monitor [p 5 0.036, p 5 0.015 and p 5 0.002, for normal-resolution mode (0.200 mm 3 voxel size), high-resolution mode (0.150 mm 3 voxel size) and low-resolution mode (0.400 mm 3 voxel size), respectively]. No statistically significant differences were found among other display types for all modes (p . 0.05). In general, no difference was found among 3 different voxel sizes (p . 0.05). In general, higher Az values were obtained for composite restorations than for amalgam restorations for all observers. For Observer 1, Az values for composite restorations were statistically significantly higher than those of amalgam restorations for MacBook and iPhone (Apple Inc., Cupertino, CA) assessments (p 5 0.002 and p 5 0.048, respectively). Conclusions: Higher Az values were observed with medical monitors when used with dedicated software compared to other display types which performed similarly in the diagnosis of recurrent caries under restorations. In addition, observers performed better in detection of recurrent caries when assessing composite restorations than amalgams.

Objectives The aim of this study was to investigate the microshear bond strength (μSBS) of different universal adhesive systems applied to hybrid computer-aided design/computer-aided manufacturing (CAD-CAM) restorative materials repaired with a composite resin. Materials and Methods Four types of CAD-CAM hybrid block materials—Lava Ultimate (LA), Vita Enamic (VE), CeraSmart (CS), and Shofu Block HC (SH)—were used in this study, in combination with the following four adhesive protocols: 1) control: porcelain primer + total etch adhesive (CO), 2) Single Bond Universal (SB), 3) All Bond Universal (AB), and 4) Clearfil Universal Bond (CU). The μSBS of the composite resin (Clearfil Majesty Esthetic) was measured and the data were analyzed using two-way analysis of variance and the Tukey test, with the level of significance set at p < 0.05. Results The CAD-CAM block type and block-adhesive combination had significant effects on the bond strength values ( p < 0.05). Significant differences were found between the following pairs of groups: VE/CO and VE/AB, CS/CO and CS/AB, VE/CU and CS/CU, and VE/AB and CS/AB ( p < 0.05). Conclusions The μSBS values were affected by hybrid block type. All tested universal adhesive treatments can be used as an alternative to the control treatment for repair, except the AB system on VE blocks (the VE/AB group). The μSBS values showed variation across different adhesive treatments on different hybrid CAD-CAM block types.

The aim of this study was to quantify the internal void volume formation in bulk‐fill resin composites with using 3D micro‐computed tomography (μCT). Class II box cavities in 4‐mm depth were prepared and treated with Clearfil S3 Bond Plus (Kuraray Medical). Five resin composites were evaluated: one conventional paste‐like (Filtek Ultimate Universal Restorative‐as the control), one conventional flowable (Filtek Ultimate Flowable Restorative), two flowable bulk‐fill (Voco Extrabase, SDR), one paste‐like bulk‐fill (Filtek One BulkFill Restorative). Resin composites were light cured using a light‐emitting diode light‐curing unit (SDI Radii Plus, SDI Limited, Australia). Samples were evaluated by μCT, and data were imported into software The NRecon (ver. 1.6.10.4, SkyScan) and CTAn (ver. 1.16.1.0, SkyScan) for 3D reconstruction, from which the percentage of void volume was calculated. Data were analyzed using the Kruskal‐Wallis test and the Mann–Whitney U‐test at a significance level of 5%. All restorative tested materials showed different levels of voids. Filtek One BulkFill Restorative showed the least void formation, which was statistically less than that of the conventional flowable composite group (p < 0.05). All other restorative materials showed similar void formation. POLYM. COMPOS., 40:2984–2992, 2019. © 2018 Society of Plastics Engineers