Digitalization era of dental education: A systematic review.

BACKGROUND: Dental education is taking its share of the digitalization of the world. Therefore, it is of value to assess the use of the digital dental education system, especially in the undergraduate period. OBJECTIVES: This systematic review concisely evaluated the use of augmented and virtual reality in preclinical dental education. MATERIAL AND METHODS: The PICOS (Population, Intervention, Comparison, Outcome, and Study design) search strategy was used with the keywords 'e-learning', 'virtual reality' and 'preclinic simulation' to search the PubMed, PubMed Central, Web of Science, and Scopus databases. RESULTS: A total of 1,774 articles were found, and 45 articles were reviewed. The level of bias in the studies was also calculated. The studies were divided into 3 main groups: computer-assisted learning (C-AL); augmented reality-assisted learning (AR-AL); and virtual reality-assisted learning (VR-AL). Augmented and virtual reality are steadily evolving, and are increasingly being used in education and healthcare. CONCLUSIONS: The evaluated technological applications enable the visualization of medical information and provide clear feedback during the learning process with increased security and reliability; thus, digital simulation systems can be used to enhance students' abilities in dentistry.

Influence of adhesive application methods and rebonding agent application on sealing effectiveness of all-in-one self-etching adhesives.

STATEMENT OF PROBLEM: The choice of adhesive application methods could affect the microleakage of self-etch adhesives. PURPOSE: To evaluate the effect of acid-etching, doubling adhesive application time, doubling adhesive coating, and rebonding agent application on microleakage of self-etch adhesives in Class V cavities. MATERIALS AND METHODS: Seventy human third molars with Class V cavities assigned to five groups according to different adhesive application protocols for the three dentin adhesives (Clearfil S3 Bond, Kuraray Medical, Okayama, Japan; Optibond All-in-One, Kerr Corporation Orange, CA, USA; G-Aenial Bond, GC Corporation, Tokyo, Japan): group 1, manufacturer's recommendations; group 2, prior acid-etching of cavities; group 3, double application time; group 4, two consecutive coats of the adhesives; group 5, rebonding application on restoration margins. After bonding, the cavities were filled with a resin composite (Filtek Supreme XT, 3M ESPE Dental Products, St. Paul, MN, USA). The teeth were thermocycled, and the specimens were examined for microleakage using methylene blue as a marker. RESULTS: For Clearfil S3 Bond and Optibond All-in-One, microleakage in groups 2 and 5 were significantly lower than other groups' enamel margins. In groups 1, 2, 4, and 5, Clearfil S3 Bond exhibited significantly more leakage than the other dentin bonding agents in dentin margins. Microleakage was significantly higher on dentinal margins compared with the enamel margins for Clearfil S3 Bond in all of the groups. Optibond All-in-One showed significantly lower microleakage in dentin margins in all groups except groups 2 and 5. CONCLUSION: Acid-etching usually promoted the reduction of microleakage in enamel margins. On the other hand, rebonding application usually contributed to the reduction of microleakage more than other methods in enamel and dentin margins. CLINICAL RELEVANCE: Acid-etching or rebonding application may contribute to reduction of microleakage of all-in-one self-etching adhesives.

Effect of the erbium:yttrium-aluminum-garnet laser or diamond bur cavity preparation on the marginal microleakage of class V cavities restored with different adhesives and composite systems.

The aim of this in vitro study was to compare the microleakage of Er:YAG laser and diamond bur on different bonding systems in class V restorations. Class V cavities were prepared with Er:YAG laser or diamond bur on 80 intact human molars. Teeth were randomly distributed into ten groups and cavities were restored with CeramX duo (DENTSPLY) or Filtek Silorane (3M/ESPE) using different bonding materials (One Coat 7.0 (Coltène), XP Bond (DENTSPLY), Clearfil Protect Bond (Kuraray), AdperSE (3M/ESPE), and Silorane System Adhesive (3M/ESPE). All specimens were subjected to thermocycling and load cycling. After being immersed in silver nitrate dye, the specimens were sectioned. Microleakage was evaluated by stereomicroscope and SEM. Data were statistically analyzed by one-way ANOVA, Kruskal-Wallis, and Mann-Whitney tests. Statistically differences were found between groups (p > 0.05) and cavities prepared with the Er:YAG laser showed higher microleakage than diamond bur. The microleakage of different bonding systems was influenced by the choice of diamond bur or Er:YAG laser for class V composite cavity preparation.

The effects of halogen and light-emitting diode light curing on the depth of cure and surface microhardness of composite resins.

AIM: Light-emitting diode light curing units (LED LCUs) have become more popular than halogen LCUs in routine dental restorative treatment. The aim of the study was to compare the effects of two conventional halogen (Hilux Plus and VIP) and two LED (Elipar FreeLight 2 and Smart Lite) light curing units on the depth of cure and the microhardness of various esthetic restorative materials. MATERIALS AND METHODS: The curing depth and microhardness of a compomer (Dyract Extra), a resin-modified glass ionomer (Vitremer), a packable composite (Sculpt It), an ormocer (Admira), a hybrid composite (Tetric Ceram), two microhybrid composites (Miris and Clearfil Photo Posterior) and, a nanofil composite (Filtek Supreme) were determined using a scraping method and a hardness tester. A total of 320 samples were prepared using the eight different materials (n = 10 samples for each subgroup). The scraping test was based on ISO 4049:2000. Vicker's microhardness testing was carried out using hardness tester (Zwick 3212). Data were analyzed using one-way analysis of variance (ANOVA), Bonferroni and the Kolmogorov-Smirnov tests. RESULTS: Best microhardness results were obtained with the LED light curing units and Tetric EvoCeram and Filtek Supreme achieved the highest hardness values. The nanofil composite, Filtek Supreme, showed the best curing depth results in all the tested light curing systems. CONCLUSIONS: The LEDs were found to be more successful than the halogen units with respect to both curing depth and microhardness properties.

Microleakage of repaired class V silorane and nano-hybrid composite restorations after preparation with erbium:yttrium-aluminum-garnet laser and diamond bur.

The aim of this in vitro study was to compare the microleakage of repaired class V resin composite restorations prepared either by Er:YAG laser or a diamond bur. Ninety-six intact human molar teeth were randomly distributed into eight groups. In the first four groups, class V cavities (3 × 3 × 3 mm) prepared on the buccal and lingual surfaces of the teeth using an erbium:yttrium-aluminum-garnet laser (VersaWave, HOYA ConBio, Japan). Similar class V cavities were prepared in the second four groups using a diamond bur (S-Class, Komet, UK). Teeth in groups 1, 2, and 5, 6 were restored with a nano-ceramic composite (Ceram.X duo, DENTSPLY), whereas a silorane material (Filtek Silorane, 3M ESPE) was used to restore cavities in groups 3, 4, and 7, 8. Two different adhesive systems (XP Bond, DENTSPLY, and Silorane System Adhesive, 3M ESPE) were also used. All specimens were aged for 7 days. New cavities (3 × 3 × 3 mm) were prepared adjacent to the old restorations with Er:YAG laser (groups I-IV) or diamond bur (groups V-VIII). Different repair materials were then applied to the new cavities using the previous two restorative materials and two adhesive systems. All teeth were subjected to thermocycling (5,000 cycles between 5 and 55°C) and axial loadcycling (30 N, 1 Hz, 2,000 cycles). Specimens were immersed in 50% w/w silver nitrate solution. Teeth were sectioned longitudinally in buccolingual direction. Stereomicroscope (Nikon SMZ 800) and SEM (JEOL JSM 5600) were used to evaluate the microleakage that existed at the interface between the old restorations and the repair materials. Data were analyzed statistically with one-way ANOVA and Tukey tests (p < 0.05). Even though no statistically significant differences were found between any of the groups, the cavities repaired with different restoratives showed slight microleakage, especially those prepared by Er:YAG laser (p > 0.05). No microleakage scores were obtained in the groups repaired with Filtek Silorane/Filtek Silorane and Ceram.X/Ceram.X. All the substances tested can be used as repair materials for immediate repair after Er:YAG laser and diamond bur. All substances tested in this study can be used as immediate repair materials after cavity preparations with Er:YAG laser or diamond bur.

Effect of Thermo-mechanical Load Cycling on Microleakage in Class II Ormocer Restorations.

OBJECTIVES: The objective of this in vitro study was to evaluate the marginal sealing ability of an ormocer in comparison with a hybrid composite when using thermocycling and load cycling procedures together in the study design. METHODS: Modified proximal Class II cavities were prepared on the mesial and distal surfaces of twenty-two human premolars. Each tooth was restored with Admira and contralaterally with TPH Spectrum. Half of all of the teeth were subjected to thermo-mechanical load cycling. After dye penetration, longitudinal sections in mesio-distal direction were prepared and examined under a stereomicroscope. Data were analyzed with Mann Whitney U test. RESULTS: The results showed that the thermo-mechanical load cycling caused a statistically significant increase in gingival microleakage when compared with the non-thermocycled and non-loaded restorations for both the materials Admira (P=0.006) and TPH Spectrum (P=0.023). CONCLUSIONS: Simultaneous load cycling and thermocycling are decisive factors in the in vitro assessment of gingival microleakage, which still remains to be a clinical problem even with the ormocer system Admira.

Abrasive effect of brushing on ormocers following acid conditioning.

The purpose of this study was to evaluate the effect of toothbrushing on the surface roughness and microhardness of Admira and Definite following acid conditioning. Half of the samples were either used as controls or brushed for 10 minutes using an electric toothbrush with slurry. The remaining specimens were stored in orthophosphoric acid with a pH of 1.9 for 24 hours and then half were brushed. The surface roughness of Admira and Definite was not significantly affected by storage under acidic conditions. However, the specimens of both materials in the control groups and the ones tested after acidic storage were found to be significantly smoother than the specimens subjected to toothbrushing alone and brushing following acid conditioning. For both materials, significantly higher values of microhardness were obtained after toothbrushing following acid conditioning than toothbrushing alone. Therefore, brushing following acid conditioning significantly affects the surfaces of the ormocers.