Search Results (5)

Objective: This study investigated the shaping efficiency of four reciprocating systems—WaveOne Gold, Reciproc Blue, Excalibur, and One Reci—in three dimensional (3D) resin models of natural mandibular premolar teeth with two canals. Methods: Forty 3D-printed mandibular premolars (Vertucci configuration type V) were divided into four groups, each of which was assigned one of the reciprocating systems. According to the manufacturer’s protocols, each canal was prepared, with pre- and post-instrumentation micro computed tomography (micro-CT) scans evaluating canal volume, surface area, percentage of unprepared canal walls, and resin reduction in the pericervical area. Instrumentation time and screw-in sensation were recorded as qualitative performance indicators. Statistical analysis was performed using one-way ANOVA and chi-square tests with a significance of (p < 0.05). Results: All systems increased canal volume and surface area, primarily in the apical third, with Reciproc Blue and One Reci achieving the largest volume. WaveOne Gold had the highest percentage of unprepared walls (27.03%) and Reciproc Blue the lowest (19.65%), though these differences were not statistically significant (p > 0.05). Reciproc Blue caused the highest pericervical resin loss (22.24%), significantly higher than Excalibur (15.09%) and One Reci (15.17%) (p = 0.035). Reciproc Blue exhibited the highest incidence of screw-in sensation (70%), while WaveOne Gold achieved the shortest instrumentation time (86.7 s), although neither variable showed statistical significance. Conclusions: All systems effectively shaped complex canal anatomies, with Reciproc Blue demonstrating the highest dentin removal and WaveOne Gold proving the most time efficient. Clinically, these findings suggest that instrument selection should balance shaping efficiency with dentin preservation. Minimizing unprepared areas and preserving pericervical dentin are essential for enhancing disinfection and reducing the risk of root fractures, ultimately contributing to the long-term success of endodontic treatment. Full article

This study aims to analyze the precision and amount of dental tissue removed during overlay preparation by experienced and less experienced operators, with and without magnification systems. Methods: Sixty-four first upper molar Frasaco Typodonts were divided into four groups: experienced operators with magnification (Group 3, EXP+LOU), experienced operators without magnification (Group 1, EXP), dental students with magnification (Group 4, STU+LOU), and dental students without magnification (Group 2, STU). Preparations including an occlusal reduction of 1.5 mm and an interproximal box of 1 mm width. The prepared teeth were scanned and analyzed using reverse engineering software (Geomagic Control X, Oqton, San Francisco, CA, USA) to evaluate preparation accuracy, dental substance removal, and comparison to a control unprepared tooth. Results: The analysis showed that the average reduction was 32.19%. Group 4 (STU+LOU) showed significantly improved accuracy with magnification compared to Group 2 (STU). Group 3 (EXP+LOU) achieved the best result with an average reduction of 23.96%, while Group 2 (STU) had the worst result with 41.28%. Conclusions: Conservative indirect restorations, such as overlays, effectively preserve dental tissue. Operator experience and magnification systems are crucial for preparation accuracy. Magnification improves precision for less experienced operators, reducing tooth volume loss by 9.1%, and enhances cavity design accuracy, ensuring a better restoration fit and minimizing the marginal gap. Full article

(1) Background: This study aimed to compare the shaping abilities of modern minimally invasive endodontic systems using natural teeth and 3D-printed resin replicas. These replicas offer a standardized approach for studying root canal preparation while eliminating the variability and scarcity of natural teeth. (2) Methods: Eleven mandibular molars with Vertucci class IV anatomy and their 3D-printed replicas (n = 132 canals) were scanned using micro-CT before and after preparation with six rotary systems. Shaping abilities were assessed by comparing volume, surface area, and unprepared areas between natural teeth and their 3D replicas, focusing on the apical third. Statistical analysis included the Shapiro–Wilk test to assess data normality and ANOVA and t-tests to compare different endodontic systems. (3) Results: Both qualitative and quantitative analyses revealed high similarity between natural teeth and 3D replicas. No significant differences in volume or surface area were found except in the apical third, where 3D replicas showed slightly larger increases in volume. (4) Conclusions: 3D resin replicas closely mimic natural teeth and provide a practical tool for assessing the shaping abilities of endodontic systems. This study demonstrates that 3D-printed models are suitable for endodontic research, offering a standardized and accessible alternative to natural teeth. Full article

This study aimed to describe a support material removal protocol (SMRP) from inside the root canals of three-dimensional printed teeth (3DPT) obtained by the microcomputed tomography (microCT) of a natural tooth (NT), evaluate its effectiveness by comparing the 3DPT to NT in terms of internal anatomy and behaviour toward endodontic preparation, and evaluate if 3DPT are adequate to assess the differences between two preparation systems. After the SMRP, twenty 3DPT printed by PolyJet™ were microCT scanned before preparation and thereafter randomly assigned into two groups (n = 10). One group and NT were prepared using ProTaper Gold^® (PTG), and the other group with Endogal^® (ENDG). MicroCT scans were carried out after preparation, and the volume increase, volume of dentin removed, centroids, transportation, and unprepared areas were compared. For the parameters evaluated, no significant differences were found between the 3DPT and NT before and after preparation (p > 0.05), and no significant differences were found between the 3DPT PTG group and the 3DPT ENDG group (p > 0.05). It can be concluded that the SMRP described is effective in removing the support material SUP706B™. PolyJet™ is adequate for printing 3DPT. Furthermore, 3DPT printed with high-temperature RGD525™ have similar behaviour during endodontic preparation with PTG as the NT, and 3DPT can be used to compare two preparation systems. Full article

Objectives: The aim of this experimental study was to evaluate the accuracy of five intraoral scanners for digitizing fully dentate unprepared maxillae and mandibulae in vitro. Materials and Methods: One maxillary and one mandibular reference model with acrylic teeth, an industrial grade reference scanner, 3D evaluation software and the intraoral scanners CS 3500, iTero HD2.9, Planmeca PlanScan, TRIOS Standard and 3M True Definition were used. Scans of the entire arches, one front and two side segments of each arch scan of maxilla and mandibula were evaluated separately for trueness and precision. In addition, visual analyses of deviation patterns, surface properties and approximal areas were performed with the aid of 3D evaluation software. Results: The intraoral scanners CS 3500, TRIOS Standard and iTero HD2.9 showed a similar level of trueness. The True Definition scanner showed lower full arch trueness compared to the TRIOS Standard and to the iTero HD2.9 (p < 0.05). Full arch trueness of the PlanScan was lower compared to the other scanners. Video-based systems showed higher numbers of datapoints per scan (127,300–169,730) compared to single image-based systems (64,115–88,124). The acquisition of interproximal areas was insufficient across all scanners. Limitations: The intraoral scanners were not tested under clinical conditions in this study. Conclusions: Apart from interproximal areas, clinically acceptable full arch trueness was achieved by the CS 3500, the iTero HD2.9 and the TRIOS Standard. Full article