BMC Oral Health最新文献

Background: This study compared the torsional resistance, bending stiffness, and cyclic fatigue resistances of different heat-treated NiTi files for minimally invasive instrumentation.

Methods: TruNatomy (TN) and EndoRoad (ER) file systems were compared with ProTaper Gold (PG). Torsional load, distortion angle, and bending stiffness were assessed using a custom device AEndoS, and toughness was calculated using the torsional data. Cyclic fatigue resistance was evaluated using another custom device (EndoC) with 45-degree curved canal in which file was rotated until fracture using dynamic pecking motion at 37 °C. One-way analysis of variance and Duncan's post-hoc comparison were conducted at a significance level of 95%. Scanning electron microscopy (SEM) analyzed fracture features and differential scanning calorimetry (DSC) analyzed phase transformation temperatures.

Results: ER and TN showed significantly lower torsional strength than PG (p < 0.05). However, ER showed a significantly greater distortion angle and the highest toughness, followed by PG and TN (p < 0.05). Both ER and TN showed similar bending stiffness, which was lower bending stiffness than PG (p < 0.05). ER showed the highest cyclic fatigue resistance (p < 0.05). SEM revealed typical fracture features across all groups, with distinct milling grooves in PG and TN, not in ER. DSC indicated that PG and ER showed a peak of austenite (Ap) at temperatures higher than body temperature, 42 °C and 40 °C, respectively, while TN showed A p at 25 °C.

Conclusion: Files for minimally invasive instrumentations typically exhibited high cyclic fatigue resistance but showed differences in the properties. The selection should depend on the root canal and tooth condition.

Background: Short dentin etching, a relatively recent technique, aims to improve resin-dentin bonding by preserving hydroxyapatite crystals within the collagen spaces. This study explores short dentin etching's potential in mitigating over-etching issues in deep proximal dentin/cementum margins, an aspect not previously investigated. This study evaluates the microtensile bond strength (μTBS) and marginal adaptation of two universal adhesives using different etch-and-rinse strategies (15-second and 3-second etching) and self-etch strategies, both immediate and post-thermal cycling and mechanical loading.

Methods: Eighty-four molars underwent μTBS testing, categorized by the universal adhesive type (Tetric Uni and Prime&Bond Uni) (n = 42) and adhesive strategy (n = 14) with half tested after 24 h and the rest post aging. Forty-two molars received occluso-mesial preparations with proximal margins in dentin/cementum and were restored accordingly. Scanning electron microscope (SEM) examination of epoxy replicas for the restoration/gingival dentin interfaces was conducted after 24 h and aging. Dentin etching patterns were assessed using SEM. A three-way ANOVA evaluated μTBS data, while a two-way ANOVA and paired sample t-test analyzed marginal adaptation data (significance level is α = 0.05).

Results: Adhesive type, strategy, and aging significantly influenced μTBS. After aging, Tetric Uni subgroups displayed higher bond strength compared to Prime&Bond Uni subgroups. Marginal adaptation was unaffected by adhesive type or strategy, although aging reduced bond strength and adaptation for both adhesives.

Conclusions: The etch-and-rinse protocol yielded higher μTBS results for the HEMA-free isopropanol-based adhesive (Prime&Bond Uni). Marginal integrity was similar for both adhesives. The 3-second and 15-second etching times produced consistent results in all tests and for both adhesives.

Clinical significance: The adhesive protocol for bonding universal adhesives to dentin is contingent on the adhesive composition.

Background: Dental caries is the most prevalent disease in elementary schoolchildren in Japan. Problematic Internet use (PIU) has increased among children; however, its association with caries has rarely been studied. We aimed to explore (1) sex differences in dental caries and (2) the association of dental caries with lifestyle and PIU among elementary school children in Japan.

Methods: From 110 elementary schools in Toyama Prefecture, 13,413 children in the 4th-6th grades (mean age, 10.5 years) participated in the Toyama Safe Internet Use Project in 2018. We inquired about lifestyle, anthropometric data, family rules for screen time, PIU, and the number of self-reported treated caries. PIU was assessed using the Young's Diagnostic Questionnaire. We defined children having ≥ 3 caries as having multiple caries. Subsequently, a modified Poisson regression analysis was performed.

Results: Overall, 12,146 children (90.7%) were analyzed. The prevalence of multiple caries was 25.7% (24.4% in boys and 27.0% in girls). In the regression analysis, the presence of multiple caries was significantly associated with being a girl(adjusted prevalence ratio (aPR) 1.13), being in higher grades (5th grade: aPR 1.13 and 6th grade: aPR 1.14), skipping breakfast (aPR 1.11), having late bedtime (10 to 11 p.m.: aPR 1.17 and ≥ 11 p.m.: aPR 1.23), tooth brushing (once a day: aPR 1.14 and not every day: aPR 1.41), having no family rules (aPR 1.20), and PIU (YDQ score 3-4: aPR 1.17). When stratified by sex, a dose-response relationship was observed between PIU and the presence of multiple caries in boys (YDQ score 3-4: aPR 1.19 and YDQ score ≥ 5: aPR 1.22).

Conclusion: Being a girl, having an undesirable lifestyle, and PIU were significantly associated with multiple self-reported caries. In addition to a having a healthy lifestyle, restricting PIU is recommended to prevent caries in children.

Background: Ameloblastoma is the most prevalent odontogenic tumor of the jaw, with a significant recurrence rate. It was conventionally classified radiographically as unilocular or multilocular. As 3D images become more common, there is a need to reassess this classification. This study aimed to conduct a multi-planar assessment of ameloblastoma using CT images, reclassify the lesions based on locularity, and correlate the locularity with imaging characteristics and recurrence.

Methods: Panoramic radiographs and CT images of histopathologically confirmed 255 ameloblastoma patients were included. The analysis encompassed imaging features including locularity, expansion, thinning, cortical perforation, and root resorption. Image characteristics associated with recurrence rate were examined, and image features were assessed based on locularity.

Results: On panoramic radiographs, most ameloblastomas (68.6%) were classified as multilocular, while 31.4% were unilocular. The CT scan demonstrated that 46.3% of the ameloblastomas were pseudo-multilocular, 29.4% were unilocular, and 24.3% were multilocular. Multilocular cases on panoramic radiographs often appeared as pseudo-multilocular on CT. Cortical perforation, root resorption, and size were significantly correlated with CT locularity types (p < 0.05). The recurrence rate was 14.11%, and the risk of recurrence was substantially reduced by mandibulectomy and a larger tumor size. No other variables were significantly related to recurrence.

Conclusion: An accurate diagnosis of ameloblastoma and surgical planning to reduce the recurrence rate are contingent upon the use of three-dimensional imaging modalities, such as CT.

Background: Traumatic dental injuries (TDIs) in early childhood exert a negative impact on the quality of life of children and their families. However, there is no evidence from cohort studies on which to base prevention strategies at the beginning of life, when children are entirely dependent upon supervision. The aim of the present study was to estimate the incidence of TDI in the first year of life and explore risk factors in a birth cohort followed up in three major cities in different regions of Brazil.

Methods: A birth cohort study was conducted with children in the cities of Porto Alegre, Salvador, and Manaus. Socioeconomic, demographic, and anthropometric characteristics were collected at baseline. Behavioral characteristics were collected when the children were six and 12 months of age. After the first year of life, clinical examinations were performed by trained, calibrated dentists for the assessment of TDI (Andreasen's criteria). Poisson regression models were used to estimate associations between the independent variables and TDI, with the calculation of crude and adjusted relative risk (RR) and respective 95% confidence intervals (CI).

Results: The incidence of TDI in the first year of life (range: 12 to 16 months) was 18.1% (95% CI: 13.6-22.6%). The multivariable analysis revealed a significantly greater risk of TDI in children from non-nuclear families (RR = 1.83; 95% CI: 1.11-3.00) as well as those whose mothers had a higher level of schooling (RR = 2.42; 95% CI: 1.04-5.63) and when tooth eruption began up to six months of age (RR = 2.30; 95% CI: 1.34-3.95). Being the first-born child was a protective factor (RR = 0.48; 95% CI: 0.27-0.87) for the occurrence of the outcome.

Conclusion: The high incidence of TDI in the first year of life indicates the need for primary prevention strategies with an emphasis on active supervision in the first months of life. Risk factors associated with TDI related to the family, mother and child suggest pathways for the planning of such strategies.

Background: This study evaluates the effects of ozone on hard and soft tissue healing when a free tissue flap is used to close wound areas lacking primary closure over autogenous grafted sites.

Methods: In our study, 24 male Wistar rats were divided into four groups: two control groups and two ozone-treated groups. All rats underwent the same surgical procedure. After surgery, the control groups received no additional treatment, while the ozone groups received topical ozone application. Ozone was applied for 2 min, three times per week, with one-day intervals, for a duration of 2 weeks post-surgery. Sacrifice was performed on the 14th day for one control and one ozone group, and on the 28th day for the remaining groups. All soft and hard tissue samples were then examined histopathologically.

Clinical trial number: not applicable.

Results: Histopathological evaluations and statistical analyses on the 14th day indicated that bone healing was significantly better in the ozone group compared to the control group (p = 0.049). For soft tissue healing, although there was no statistically significant difference between the ozone and control groups, proportional values showed better recovery in the ozone-treated groups compared to the controls.

Conclusions: The present study concludes that ozone has a positive effect on new bone formation in the early stages; however, it showed no statistically significant effect on soft tissue healing. We believe that further comprehensive studies would be beneficial to confirm these findings.

Background: Repairing composite resins is a less invasive alternative to complete restoration replacement. To achieve a successful bond between the existing and newly applied composite materials, various surface preparation methods, such as sandblasting and acid etching, have been explored. The aim of the study was to evaluate the effect of different surface treatments on the repair bond strength of a universal nanohybrid composite resin restorative material before and after thermal aging, by utilizing a micro-shear bond strength (µSBS) test.

Methods: For the micro-shear bond strength test, a total of 120 cylindrical (3mmX2mm) nanohybrid resin based composite specimens were prepared. The prepared specimens were divided into three groups (n = 40/per group) based on surface treatment methods: a non-aged group, 10,000 thermal cycle aging and 50,000 thermal cycle aging. The aged and non-aged specimens were further divided into four groups according to adhesive application modes and surface pretreatment methods: 1.universal adhesive/self-etch mode, 2.aluminum oxide sandblasting + universal adhesive/self-etch mode, 3.universal adhesive/etch-and-rinse mode, 4.aluminum oxide sandblasting + universal adhesive/etch-and-rinse mode. Subsequently, 0.8mmX2mm disc shape light cure resin based composite specimens were applied with a direct placement technique on the treated surfaces of all samples for repair. µSBS test was performed using a universal testing machine at a crosshead speed of 1 mm/min. Kruskal-Wallis and Mann-Whitney tests were performed for statistical analysis.

Results: The µSBS values of the non-aged group were higher than those of the 10,000 and 50,000 thermal cycle groups, with no significant differences within the non-aged subgroup (p > 0.05). In the aged groups, significant differences were observed between adhesive application modes and surface treatments. Specifically, the etch-and-rinse mode showed higher bond strengths than the self-etch mode after 50,000 thermal cycles (p < 0.05). Sandblasting combined with universal adhesive (self-etch mode) improved bond strength, especially in the 10,000 thermal cycle group (p < 0.05).

Conclusion: Aging reduced the bond strength of composite resin repairs, with the etch-and-rinse mode outperforming the self-etch mode in aged specimens. Sandblasting alone did not enhance bond strength. These findings highlight the importance of considering aging and adhesive strategies to optimize repair outcomes, with further research needed on long-term durability.

Background: Epidemiologic data on the number of cleft lip and/or palate (orofacial cleft (OFC)) births in Switzerland are currently sparse. However, this knowledge is essential for better understanding the etiologies underlying the various cleft phenotypes and providing expectant parents with the best possible healthcare planning and counseling.

Methods: This is the first descriptive study to report data on the prevalence of the various cleft types, their sex, and regional distributions in Switzerland. Data for the years 1998-2021 were obtained from the Swiss Federal Statistical Office. Due to the notable initial underreporting of cleft cases from 1998 to 2006, this period was omitted from the final analyses.

Results: Between 2007 and 2021, the prevalence of all Swiss OFC cases per 10,000 live births was 12.5, with a stable trend. Cleft lip was the least common anomaly. Except for cleft palate, which was more common in females, males were generally more affected by OFC than females. There was no discernible regional trend for any of the malformations, even though the prevalence differed throughout the seven Swiss regions.

Conclusions: This study presents the first descriptive epidemiologic profiles for OFCs in Switzerland and emphasizes the importance of nationwide OFC registries with an accurate and reliable reporting system for the benefit of current and future patients with clefts, their parents or caregivers, and society as a whole.

Background: Treatment of gingival recessions through surgical approaches is a common periodontal intervention. There is a rise in using biologics in root coverage procedures. As it has been shown that hyaluronic acid (HA) promotes wound healing, this review aimed to assess its efficacy in the treatment of gingival recessions.

Methods: An electronic search was conducted across several databases (Medline/ PubMed, Embase, Scopus, Web of Science) supplemented by manual searching. The effectiveness of using HA was evaluated using various outcome measures, with the primary indicators being complete and mean coverage, recession depth, and recession width. Meta-analysis was performed to estimate the differences between test and control sites.

Results: A total of 9 studies were eligible for inclusion. The overall analysis showed no significant difference between coronally advanced flap (CAF) + HA and control groups (CAF alone or CAF + sub-epithelial connective tissue graft) in terms of mean root coverage with a mean difference of 8.23 (95% confidence interval -3.06 to 19.53) and p = 0.12.

Conclusions: The current evidence suggests that the local application of HA may have some slight benefits over CAF alone in certain parameters. Nevertheless, its application does not add significant benefits to connective tissue graft. Given the high heterogeneity among the studies, further research with extended follow-up periods is necessary to better understand the clinical implications of using hyaluronic acid in this context.

Trial registration: CRD42024580649.

Objective: To investigating whether osteogenic differentiation of osteoblasts promoted by tension force (TF) is mediated by ephrinB2-EphB4 signaling.

Methods: TF was applied to MC3T3-E1 cells, then CCK-8 and live/dead staining were used to detect cell proliferation. Levels of osteogenic differentiation-related factors were detected by ALP staining, ARS staining, qPCR and western blot. NVP-BHG712 was used to block EphB4 receptor. Establishing a rat orthodontic tooth movement (OTM) model, ephrinB2-Fc and NVP-BHG712 were used to treat rats. Micro-CT and H&E staining were used to detect alveolar bone. Changes of MAPK pathways were detected to investigate whether they were downstream of ephrinB2-EphB4 signaling in mediating TF promote osteogenic differentiation.

Result: We explored the effect of TF on MC3T3-E1 cells, and found that TF significantly promoted osteogenic differentiation, but when EphB4 receptor was blocked, the promotion was inhibited. In vivo, we found that TF improved alveolar bone formation through ephrinB2-EphB4 signaling. Further investigation into the signaling pathways revealed that TF significantly increased levels of MAPK pathways, however, when EphB4 receptor was blocked, only the promotion of p-ERK1/2 was decreased.

Conclusion: TF promotes osteogenic differentiation through ephrinB2-EphB4 signaling and ERK1/2 pathway is a downstream of ephrinB2-EphB4 signaling partially mediate mediates TF-induced promotion of osteogenic differentiation.