BMC Oral Health最新文献

Background: Distalization in orthodontics is one of conservative treatment modalities that result in gaining space especially in dental orthodontic cases of class ΙΙ molar relationship.

Aim: A prospective parallel double group randomized clinical trial aimed to compare the distalization effects of the skeletally anchored modified Leaf Expander versus the skeletally anchored modified conventional Hyrax Expander. Skeletally anchored distalizers for orthodontic treatment are better than dentally anchored distalizers (Superiority).

Patients and methods: Thirty patients (15-18 years) who were requiring maxillary molar distalization, were randomly allocated into two groups (n = 15 each). Group 1 received the modified skeletally anchored self-activated Leaf Expander, and Group 2 received the modified skeletally anchored conventional Hyrax Expander. Pre- and post-distalization lateral cephalometric radiographs and digital dental models were analyzed for skeletal, dental, and arch dimensional changes. The primary outcomes of the current study were: Arch length, Inter-canine width, Inter-first premolar width, Inter-second premolar width and Inter-first molar width, all these parameters were assessed after completion of distalization and result in class 1 molar relationship. Treatment duration and adverse events were also recorded. Statistical analysis included paired t-tests and independent t-tests, with Bonferroni correction (α = 0.0045) applied for multiple comparisons. Effect sizes (Cohen's d) were calculated to assess clinical relevance.

Results: Both appliances achieved significant distalization of maxillary first molars as assessed on lateral cephalometric analysis (Leaf: -7.65 ± 0.74 mm(95% CI: -8.06 - -7.24); Hyrax: -6.95 ± 0.82 mm(95% CI: -7.41 - -6.49) with effect size (d) 0.87) with minimal angular changes. Treatment duration was significantly shorter for the Hyrax group (6.52 ± 1.52 months (95% CI: 6.02-7.54)) compared to the Leaf group (10.43 ± 1.52 months (95% CI: 9.94-11.46); p < 0.001, effect size (d) = 2.35). Skeletal parameters (SNA, SNB, ANB, FH-MP), incisor inclinations (U1/PP, L1/MP), overjet, and arch dimensions showed no statistically significant differences after Bonferroni correction, though some differences were clinically relevant. Mild gingival enlargement occurred in three patients, managed conservatively.

Conclusion: Both appliances effectively achieved significant distalization of maxillary molars; however, the modified skeletally anchored conventional Hyrax Expander achieved distalization faster than the modified skeletally anchored Leaf Expander.

Trial registration: ClinicalTrials.gov Identifier: NCT06308640. Retrospectively registered on 29 February 2024. (first enrolment).

Background: There is a lack of comprehensive comparative data assessing the accuracy of multiple intraoral scanners (IOSs) across both partially and completely edentulous cases, particularly in the presence of variable implant positions. The aim of this study was to assess the effect of IOSs and implant positions in 4-unit and All-on-4 restorations on the trueness and precision of digital impressions.

Methods: Two maxillary resin models were fabricated: a partially edentulous arch planned for a 4-unit fixed dental prosthesis (FDP) with implants at the canine and first molar sites, and a completely edentulous arch for an All-on-4 FDP. Each model was scanned (n = 10 each) using five IOSs: Omnicam AF, CS 3800, Trios 3 A, Medit i500, and Primescan AC. Scan data were analyzed using Geomagic Control X to assess trueness and precision. Statistical analysis was performed using three-way ANOVA, followed by two-way ANOVA and post hoc testing (p < 0.05).

Results: Regarding trueness in the 4-unit FDP group, CS3800 exhibited the highest RMS in anterior and posterior implants. In the All-on-4 group, Trios and Medit i500 showed the lowest RMS in anterior implants, and Medit i500 showed the lowest RMS in posterior implants. CS3800 showed the highest RMS in both the implant positions. Regarding precision in the 4-unit FDP group, Trios and Primescan achieved the lowest RMS. CS3800 and Medit i500 showed the highest RMS in posterior implants. In All-on-4, Omnicam showed the least RMS in anterior implants, while Primescan the least in posterior implants. All scanners showed less precision in posterior implants in both models.

Conclusions: Under controlled in vitro conditions, differences in trueness and precision were observed among intraoral scanners, depending on implant position and restoration type. In All-on-4 restorations, Medit i500 showed the highest trueness. Whereas, in 4-unit FDPs, Trios 3 and Primescan exhibited the highest precision. Anterior and posterior implant positions exhibited varying levels of trueness and precision deviation across scanners.

Clinical significance: Intraoral scanner accuracy is influenced by implant position and prosthesis configuration, with posterior implant positions generally exhibiting reduced precision under in vitro conditions. These findings represent statistically significant differences observed within an experimental model and do not establish scanner ranking, clinical acceptability thresholds, or in vivo scanner suitability.

Background: Dental pulp inflammation and impaired tissue repair remain critical challenges in endodontic therapy, often exacerbated by hypoxia and dysregulated immune responses.

Methods: We developed a procyanidin-copper-loaded oxygen-generating microneedle hydrogel (CA-PCC-CAT) releasing active components into deeply infected pulp tissue in a pH-responsive manner to exert potent antioxidative and anti-inflammatory effects.

Results: In vitro experiments demonstrated that the hydrogel effectively protected hDPSCs through its multifunctions, including antibacterial activity, antioxidative stress modulation, anti-inflammatory action, and hypoxia alleviation. Simultaneously, it augmented macrophage efferocytosis by scavenging reactive oxygen species (ROS), thereby facilitating the clearance of apoptotic cells and enhancing tissue repair.

Conclusions: This study represents a promising strategy for developing multifunctional biomaterials to amplify the anti-inflammatory capacity of hDPSCs and advance the field of pulp preservation and regenerative therapy.