Journal of Dental Research, Dental Clinics, Dental Prospects最新文献

Background: With advancements in orthodontic technology, treatment durations have shortened, often concluding at earlier ages. This shift prompts scrutiny of contemporary retention and post-treatment protocols. The study aimed to assess current professional preferences, compare them against patient age and treatment duration, and investigate the potential impacts of reduced treatment times on professional protocols, particularly when treatment concludes before pubertal growth.

Methods: A questionnaire comprising 12 multiple-choice questions focused on active treatment and retention phases was developed using an online survey platform. It was distributed to licensed orthodontists engaged in patient treatment. Bivariate analysis was conducted using ANOVA and the Kruskal-Wallis test, with pairwise comparisons facilitated by the Dwass-Steel-Critchlow-Fligner method.

Results: Of 743 respondents, representing a 32% response rate, approximately 70% reported initiating treatment with fixed appliances in pre-pubertal patients. The most prevalent treatment combination involved commencing treatment during early permanent dentition and lasting between 12 to 24 months, resulting in treatment completion before full growth maturation. No discernible individualization was observed in retention protocols or post-retention follow-ups. Traditional retainer prescription post-orthodontic therapy was unanimous among respondents. Notably, experienced orthodontists tended to prefer regular patient visits for follow-up, while less experienced counterparts discharged patients after 12 months.

Conclusion: Contemporary orthodontic treatments are characterized by shorter durations, yet orthodontists have not adopted retention and post-treatment follow-up practices accordingly. There is a pressing need for evidence-based guidelines to develop protocols tailored to the shorter treatment durations and the increasing prevalence of younger patients completing treatment.

Background: The sealer's interfacial adaptability is one of the critical factors for successful root canal therapy. This study evaluated and compared the interfacial adaptability of newly prepared nano-tricalcium silicate-58s bioactive glass-based endodontic sealer (C₃ S-BG-P) to root dentin with two bioactive sealers Nishika Canal Sealer BG and BioRoot^TM RCS.

Methods: Thirty newly extracted single-rooted lower premolars were decoronated and instrumented. The roots were assigned to three groups: C₃ S-BG-P, Nishika Canal Sealer BG, and BioRoot^TM RCS (n=10) and obturated with the single-cone method. Each root was sectioned horizontally to obtain three slices at 2, 5, and 10 mm from the apex. The width of the gaps at the sealer‒dentin interface from each section's mesial and distal sides was measured under a field emission scanning electron microscope (FESEM) at×1.0 using the Digimizer software program. One-way ANOVA and post hoc Tukey tests for multiple comparisons were used to interpret and analyze the collected data.

Results: The mean gap width at the sealer‒dentin interface of C₃ S-BG-P and Nishika Canal Sealer BG was significantly less than that of BioRoot^TM RCS at all root sections (P≤0.05). However, the mean gap width at the sealer‒dentin interface of C₃ S-BG-P was not significantly different from Nishika Canal Sealer BG (P>0.05). Moreover, there were greater interfacial gaps at the apical level than at the coronal level for all the tested sealers.

Conclusion: C₃ S-BG-P exhibited interfacial adaptation that was nearly comparable to Nishika Canal Sealer BG and superior to BioRoot^TM RCS.

Background: Synthetic fibers have many benefits in clinical practice; however, they cause microplastic pollution, and their unaffordable price increases treatment costs. Natural silk fibers require biocompatibility assessment. This study investigated the effects of natural and synthetic fiber-reinforced composites (FRCs) on the cytotoxicity of fibroblast cell lines.

Methods: Three commercial synthetic fibers (polyethylene, quartz, and E-glass) and two silk fibers from Bombyx mori and Samia ricini cocoons were employed. These fibers were made into FRC samples (n=6) by impregnation in flowable composite using a brass mold (25×2×2 mm). NIH/3T3 mouse fibroblasts were cultured in Dulbecco's modified eagle medium, supplemented, and seeded in 2×10⁴ cells/mL. They were stored at 37 °C under 5% CO₂ for 24 hours. The FRC samples were made into powder, eluted in dimethylsulfoxide, continued with PBS, supplemented with Dulbecco's modified eagle medium (DMEM), and exposed to cells for 24 hours. Blank (medium only) and control (cells and medium) samples were included. Subsequently, MTT was added for 4 h and read by enzyme-linked immunosorbent assay (λ=570 nm). Cell viability (%) was calculated and analyzed using one-way ANOVA (α=0.05).

Results: All groups of FRCs showed>80% cell viability. One-way ANOVA showed no significant difference between FRC groups regarding the viability of fibroblast cell lines (P>0.05).

Conclusion: Both natural silk and synthetic fibers exhibit low cytotoxicity to fibroblast cell lines. B. mori and S. ricini silk fibers showed the potential to be used as alternative synthetic fibers.

Background: Chewable vitamins are dietary supplements in which vitamins are combined with a flavor that appeals to children. The acidic nature of some vitamins and some flavoring agents may cause dental erosion. We investigated the effect of children's chewable vitamin supplements on the loss of minerals in teeth.

Methods: Forty-two human tooth enamel samples were prepared and randomly assigned to seven groups (n=6). Six groups contained different chewable vitamin tablets dissolved in deionized water, and a control group contained only deionized water. Each tablet was ground before its dissolution, and its pH was measured. Each tooth sample was immersed in a vitamin solution and artificial saliva in periodic cycles for 14 days. Each sample was weighed before and after immersion to calculate its weight loss percentage. Scanning electron microscopy was used to investigate the morphology of the enamel surfaces. For statistical analysis, the weight loss percentages between groups were compared using Welch's ANOVA, followed by post hoc Dunnett's T3 analysis (P<0.05).

Results: All the tested supplements were acidic, with a pH range of 2.99‒4.77. Most of the vitamin groups tested led to significant weight loss; it was greater for the vitamin C groups than the multivitamin groups. Scanning electron microscopy revealed erosion and destruction of enamel surfaces following vitamin exposure.

Conclusion: All the chewable vitamin supplements were acidic, with the majority potentially eroding enamel. The erosive potential was less pronounced in vitamin supplements containing minerals.

Background: Candida albicans in the oral cavity causes denture-induced stomatitis, but current treatments have side effects and contribute to drug resistance. Selenium nanoparticles (SeNPs) show promise as an antimicrobial agent, but their effectiveness against C. albicans is unknown and warrants further research.

Methods: Acrylic resins containing different concentrations of SeNPs (0.2, 2, and 10 g/mL) were formulated and evaluated against C. albicans isolates. The minimum inhibitory concentration (MIC) of SeNPs was determined, and a fungal biofilm was developed on acrylic samples. The quantity of biofilm was assessed using scanning electron microscopy (SEM) and optical density (OD) at 570 nm after staining with crystal violet. Statistical analysis was performed using STATA software, with Kruskal-Wallis and Mann-Whitney tests to establish significance (P<0.05).

Results: The MIC of SeNPs was 25%. The OD in the group with 10% SeNPs was 0.477 and 0.547 in the group with 0.2%. Kruskal-Wallis test results showed that at least two groups among those studied had significant differences (P=0.0273). In pairwise comparisons, the differences between all the groups were statistically significant (P=0.049). SEM analysis confirmed the destruction of C. albicans cell walls, leading to reduced colonization, with the 10% group showing the highest efficacy.

Conclusion: The study demonstrated that SeNPs are effective against C. albicans colonization when combined with acrylic resin. Specifically, SeNPs exhibited enhanced antifungal properties at a concentration of 10%. These findings confirm that SeNPs are a promising alternative to traditional antifungal agents for treating oral candidiasis and denture-induced stomatitis.

Background: The wear resistance of lithium disilicate glass ceramics remains inadequately understood. Therefore, the primary objective of this in vitro study was to digitally assess the wear characteristics of lithium disilicate and zirconia-reinforced lithium disilicate pressable ceramics following chewing simulation.

Methods: Twenty-two onlay ceramic restorations were fabricated on epoxy dies replicated from the maxillary first premolar ivory tooth master die. The onlay samples were randomly allocated to two equal groups (n=11) based on the material used: group L (lithium disilicate [IPS e.max Press]) and group Z (zirconia-reinforced lithium disilicate [Vita Ambria]). Self-adhesive resin cement was used to cement all of the samples. Each sample was occluded with the buccal cusps of healthy human upper first premolar teeth (n=22). Subsequently, all the samples were scanned using an intraoral scanner (Medit i500) at baseline and after chewing simulation. The acquired standard tessellation language (STL) files of baseline and post-chewing simulation data were superimposed, and the volumetric loss (mm³) and wear depth (μm) of the materials and their enamel antagonists were calculated. Statistical analysis was performed using independent t-test (P=0.05).

Results: There was no statistically significant difference in the wear behavior of Vita Ambria compared to IPS e.max (P<0.05). Similarly, there was no statistically significant difference in the wear behavior of their enamel antagonists (P<0.05).

Conclusion: IPS e.max Press and Vita Ambria ceramics demonstrated comparable wear behavior.

Background: This investigation assessed the impact of irrigation activation systems on the depth of penetration of intracanal medicaments into dentinal tubules.

Methods: Ninety-six mandibular premolar teeth were prepared using ProTaper Next up to size X3. The teeth were randomly divided into four groups based on the final irrigation activation systems (n=24): group 1: EndoActivator, group 2: XP-Endo Finisher, group 3: Passive ultrasonic irrigation (PUI), and group 4: control. After the final irrigation, all the samples were divided into two subgroups (n=12): subgroup A: calcium hydroxide (Ca(OH)₂ ) and subgroup B: modified triple antibiotic paste (mTAP). Statistical analysis involved three-way analysis of variance (ANOVA).

Results: EndoActivator, XP-Endo Finisher, and PUI activation methods significantly increased the penetration of intracanal medicaments compared to conventional needle irrigation (P<0.05). The XP-Endo Finisher group exhibited the highest penetration percentage and maximum penetration depth, showing a statistically significant difference from the EndoActivator group (P<0.001). No significant difference was observed between XP-Endo Finisher and PUI, nor between PUI and EndoActivator (P>0.05). mTAP showed a higher percentage of dentinal tubule penetration than Ca(OH)₂, although no significant difference was found in maximum penetration depth. The coronal region demonstrated the highest penetration percentage and depth, while the apical region showed the lowest.

Conclusion: This study showed the effectiveness of XP-Endo Finisher in improving the penetration of intracanal medicaments into dentinal tubules. The findings emphasize the importance of selecting appropriate irrigation activation systems to improve treatment outcomes in endodontics. By demonstrating the effectiveness of advanced systems like XP-Endo Finisher, this research supports their integration into routine clinical practice for better endodontic success.

Background: Modifying the dental implant's surface texture enhances its biological response to the bone and implant‒tissue interface, resulting in the successful support of forces. This study assessed the impact of sandblasting, sandblasting plus acid etching, Er,Cr:YSGG laser, and propolis implant surface treatments and occlusal load on the osseointegration of titanium dental implants in dogs.

Methods: Seventy-two titanium dental implants with a diameter of 4 mm and a length of 10 mm were divided into four groups according to implant surface modifications (n=18 for each group): group A: sandblasting plus acid etching, group B: sandblasting with Al₂ O₃, group C: Er,Cr:YSGG laser, group D: propolis coating. Twenty-four local breed male dogs were used. Premolar teeth (P1, P2, and P3) were extracted on the left side of the mandible, and after 12 weeks of bone healing, implants were unilaterally installed. The osseointegration at three study times from implant installation (14, 90, and 180 days) was evaluated. The dog jaws were scanned using an intraoral scanner for the virtual design of screw-retained three-unit crowns after 90 days of osseointegration. Final radiographs were taken before the animals were sacrificed at 14, 90, and 180 days, and the histological analysis was performed.

Results: Radiographic analysis showed new bone formation (NBF) along and in contact with the implant surface of the treated groups. The histological analysis after 14 days in groups A and B revealed a uniform and ongoing pattern of bone growth and many osteoblasts with few osteocytes within lacunae in new bone trabeculae. Group C showed an increase in the number of osteoblasts lining thin bone trabeculae. Group D showed a generative power concerning bone. At 90 days, there was increased bone ingrowth, and the new bone matured in all the treated implant groups. At 180 days, dense mature bone apposition was in direct contact with delayed-loaded implant surfaces.

Conclusion: A radiographic examination revealed that surface modification significantly impacted osseointegration, with a strong bond between the implant surface and the surrounding bone. The histological sections at the 14-day interval revealed obvious bone remodeling activity, especially in sandblasting plus acid etching and sandblasting-modified implant surface groups. At the 90-day interval, bone ingrowth had increased, and the new bone became mature, especially in sandblasting and propolis surface modification groups. After 180 days of the delayed-loaded implant osseointegration, differences were observed between different implant-treated groups with a remarkable remodeling of the bone, especially in the propolis coating group.

Background: This in vivo study assessed the accuracy of single-tooth monolithic zirconia crowns made using an intraoral scanner (IOS) and computer-aided design/computer-aided manufacturing (CAD/CAM) technology.

Methods: Thirty patients requiring single posterior crowns were selected. The teeth were prepared with a deep chamfer finish line with a 1-mm extension subgingivally and a 1-mm reduction in all surfaces by one prosthodontist. The gingival margins were retracted using a gingival retraction paste before making impressions using a Trios scanner. All the digital impression files were sent to one laboratory using the dental designer software (3Shape, Copenhagen, Denmark). After completing the milling and sintering processes, the crowns were dyed and glazed. After removing the temporary crown, the qualitative assessment of proximal contacts of definitive monolithic zirconia crowns was performed according to the CDA criteria. Data were analyzed with Friedman's two-way analysis and independent t-test at α=0.05.

Results: The difference in axial and total gaps between premolar and molar teeth was not significant; however, the mean marginal gap of molars was higher than that of the premolars (P=0.043). Furthermore, the comparison of the axial, total, and marginal gaps between the upper and lower jaws showed no significant difference (P>0.05). The distribution of occlusal and proximal contacts indicated 60% and 66.7% proper contacts and no contacts in 6.7% and 10% of cases, respectively.

Conclusion: Using IOSs could result in accurate monolithic zirconia crowns in terms of adaptation. Also, most occlusal and proximal contacts did not need any adjustments.

Background: Tomato, renowned for its tooth-whitening properties due to its hydrogen peroxide and peroxidase enzyme content, requires formulation for enhanced applicability. This study assessed the dental whitening efficacy of a patch containing tomato juice as the active ingredient.

Methods: Tomato juice patches were formulated at concentrations of 55%, 60%, and 65%. A control group (C) containing a 12% hydrogen peroxide patch was also included. A matrix layer of the patches was prepared using the solvent casting method at 40 for 18 h, with Tegaderm^TM applied as the backing layer. For the dental whitening procedure, each group of patches was applied to the labial surface of anterior stained teeth (n=6/group) for 3 h, repeated 14 times. Tooth brightness was evaluated qualitatively and quantitatively using digital dental photo CIEL*a*b* analysis. Meanwhile, enamel surfaces were examined under a scanning electron microscope (SEM). Repeated-measures analysis of variance (ANOVA) was employed for statistical analysis.

Results: The application of tomato juice patches led to enhanced tooth brightness. The patch containing 65% tomato juice significantly improved stained tooth brightness (P<0.05). SEM analysis revealed less enamel erosion with the 65% tomato juice patch compared to the 12% hydrogen peroxide patch.

Conclusion: Tomato juice patches effectively increased tooth brightness while minimizing demineralization. Further research is needed to optimize formulation and explore its potential.