Journal of Dental Sciences最新文献

Anterior open bite (AOB), characterized by the lack of vertical overlap between upper and lower anterior teeth, poses a considerable challenge in orthodontics. The condition depends on many factors that combine to render it difficult to achieve post treatment stability. AOB is commonly classified as dental, skeletal, or functional on the basis of the clinical presentation and causative factors. Traditionally, skeletal AOB necessitates surgical intervention, whereas nonsurgical approaches such as extrusion arches and the Multiloop Edgewise Archwire Technique (MEAW) can be employed in more straightforward cases. Functional appliances are reserved for situations in which a patient's growth potential offers the possibility of effectively addressing AOB. This review presents a strategic treatment approach for addressing AOB, taking into account the classification and severity of the condition. The proposed SHE framework describes the use of mini-screws (S) for anchorage and vertical control, encouragement to correct habits (H), and the utilization of extractions and elastics (E). By incorporating extra-radicular mini-screws, AOB closure is achieved through anterior retraction in extraction cases or whole arch distalization of dentition with elastics in non-extraction cases. This framework emphasizes habit correction through a regimen of oral myofunctional therapy (OMT) and habit-correcting appliances to enhance posttreatment stability. This review suggests that nonsurgical correction is viable in the majority of cases, whereas surgical intervention should be reserved for severe cases of skeletal vertical overgrowth or horizontal discrepancies.

Background/purpose

The etiology of the ectopic eruption (EE) of the maxillary first permanent molars (FPM) remains unclear and controversial. This study was designed to explore the dental and skeletal factors for EE of the FPM in children.

Materials and methods

Children aged 6–10 years were recruited to this study. Subjects were assigned to the ectopic eruption group (EEG) and the normal eruption group (NEG). Lateral cephalometric radiographs and panoramic radiographs were measured by angular and linear indices.

Results

The prevalence of EE of maxillary FPM was higher in males and at younger ages. Subjects with skeletal class III malocclusion were more likely to be diagnosed with EE of maxillary FPM. The SNA, ANB, FMIA, Wits, Ptm-A, ANS-PNS, overbite, and overjet were significantly different between the EEG and the NEG. The length of the posterior region of the maxillary alveolar bone, U6-OP, and eruptive angulation of the maxillary FPM were statistically different between the two groups.

Conclusion

Male sex, skeletal class III malocclusion, mesial inclination of the maxillary FPM, hypoplasia of the maxilla, and insufficient length of the posterior region of the maxillary alveolar bone were related to EE of the maxillary FPM.

Background/purpose

In the field of conservative dentistry and endodontics, mineral trioxide aggregate (MTA), commonly used, possesses advantages such as biocompatibility, antimicrobial properties and osteogenic potential. This study investigated the feasibility of utilizing membrane form mineral trioxide aggregate (MTA) as a barrier membrane in guided bone regeneration (GBR) procedures.

Materials and methods

Membranes were electrospun from three different formulations: 15 w/v% Polycaprolactone (PCL), 13 w/v% PCL + 2 w/v% MTA (2MTA), and 11 w/v% PCL + 4 w/v% MTA (4MTA). Physicochemical and mechanical properties of the electrospun membrane were compared, encompassing parameters such as surface morphology, fiber diameter distribution, chemical composition, phase identification, tensile stress, pH variation, and water contact angle. Moreover, the antimicrobial properties against of the electrospun membranes were assessed through direct exposure to streptococcus aureus (S. aureus) and candida albicans (C. albicans). Additionally, on the 7th day, biocompatibility and cell attachment were investigated with respect to L929 (fibroblast) and MC3T3 (pre-osteoblast) cells. Inhibition of L929 cell infiltration and the expression of osteogenic related genes including osteocalcin (OCN), alkaline phosphatase (ALP), and runt related transcription factor 2 (RUNX2) in MC3T3 cells on 7th and 14th days were also investigated.

Results

PCL, 2MTA, and 4MTA exhibited no statistically differences in fiber diameter distribution and tensile stress. However, as the MTA content increased, wettability and pH also increased. Due to the elevated pH, 4MTA demonstrated the lowest viability S.aureus and C.albicans. All membranes were highly biocompatibility and promoted cell attachment, while effectively preventing L929 cell infiltration. Lastly 4MTA showed increase in OCN, ALP, and RUNX2 expression on both 7th and 14th day.

Conclusion

The membrane form MTA possessed characteristics essential for a novel barrier membrane.

Background/purpose

We suspected that there might be an interaction between sugar intake and tobacco exposure on the risk of dental caries. The study aimed to investigate the associations of sugar intake or tobacco exposure with the risk of dental caries.

Materials and methods

This cross-sectional study obtained data of 18804 participants from National Health and Nutrition Examination Survey (NHANES) between 2011 and 2018. Weighted univariable and multivariable logistic regression models were applied to explore the associations of total sugar intake or tobacco exposure with the risk of dental caries. The relative excess risk of interaction (RERI), attributable proportion of interaction (API), and synergy index (SI) evaluated the interaction between total sugar intake and tobacco exposure on the risk of dental caries. The effect size of odds ratio (OR), and 95% confidence interval (CI) was inputted.

Results

The OR of dental caries in adults with cotinine >10 ng/mL was 1.59 (95%CI: 1.38–1.82). The increased risk of dental caries was found in people with total sugar >19.5%E compared to those with total sugar ≤19.5%E (OR = 1.55, 95%CI: 1.34–1.78). Compared to people with cotinine ≤10 ng/mL and total sugar ≤19.5%E, adults with cotinine >10 ng/mL and total sugar >19.5%E were correlated with elevated risk of dental caries (OR = 2.76, 95%CI: 2.29–3.33). The interaction indicators RERI was 0.980 (95%CI: 0.413–1.547), API was 0.355 (95%CI: 0.192–0.517), and SI was 2.250 (95%CI: 1.344–3.767).

Conclusion

There might be interaction between sugar intake and tobacco exposure on the occurrence of dental caries in adults.

Background/purpose

Helicobacter pylori has been found to be related to periodontitis, and the oral cavity has been considered a reservoir for H. pylori gastritis infection. Thus, this study evaluated the effect of mouthwash containing poly l-Lysine and glycerol monolaurate on inhibiting H. pylori growth, biofilm formation, cell cytotoxicity, adhesion ability, cagA mRNA expression, and pro-inflammatory cytokines stimulated by H. pylori.

Materials and methods

Nineteen H. pylori strains were isolated from the oral cavity. The effectiveness of mouthwash containing poly l-Lysine and glycerol monolaurate was examined for its ability to inhibit H. pylori growth and biofilm formation and was tested for cell viability in oral epithelial cells (H357), gastric adenocarcinoma cells (AGS), and periodontal ligament cells (PDL). Additionally, the mouthwash was tested for reducing cagA mRNA expression, adhesion ability to H357 and AGS cells, and pro-inflammatory cytokines stimulated with H. pylori in AGS and PDL cells.

Results

The mouthwash containing poly l-Lysine and glycerol monolaurate could eradicate the biofilm by 14.9–19.9% after incubation at 5 min, and cell viability revealed 77.2, 79.8, and 100.0% for AGS, H357, and PDL cells, respectively. Moreover, the mouthwash containing poly l-Lysine and glycerol monolaurate could down-regulate cagA mRNA expression, reduce adhesion of H. pylori by approximately 9.5–47.8% for H357 cells and 24.5–62.9% for AGS cells, and decrease pro-inflammatory cytokines, especially interleukin-8, stimulated with H. pylori.

Conclusion

Mouthwash containing poly l-Lysine and glycerol monolaurate could inhibit H. pylori growth and reduce their virulence expression. The mouthwash also revealed low cytotoxicity to oral and gastric cells.

Background/purpose

Self-assessment in dental education is considered a fundamental skill for proficient oral healthcare providers. While previous studies looked at self-assessment in education, few have done so at Japanese institutions. This study aimed to assess potential associations between gender and self-assessment skills in Japanese dental students.

Materials and methods

Dental students from Niigata University (n = 301) completed preclinical prosthodontic exercises and self-assessed their practical exam performance. Three calibrated faculty evaluated students’ work using the same rubric. The difference between student self-assessment score and mean faculty grade was defined as the student-faculty (S-F) gap, indicating how accurately students evaluated their work. The gap scores were stratified by quartiles by faculty grade and by gender. Regression analysis was used to investigate potential associations.

Results

Students mean S-F gap was 2.9 ± 10.5 % with a significant negative association to faculty grades (coefficient, −0.32; P < 0.001). There was no significant difference between male and female students for faculty grades, self-assessment scores, and S-F gaps. When stratified by quartile, mean S-F gaps of bottom quartile students (5.7 ± 11.9 %) were significantly higher than the rest of the class (1.9 ± 9.8 %; P = 0.01), while the mean S-F gaps of students in the top quartile (−0.8 ± 10.2 %) were significantly lower than the rest of the class (4.2 ± 10.3 %; P < 0.001).

Conclusion

Niigata University students generally overestimated their performance. Students with higher faculty grades self-assessed themselves more accurately than students with lower faculty grades. Gender did not influence S-F gaps, despite dentistry in Japan shifting toward a female-dominated field.