Journal of oral science最新文献

Purpose: To evaluate the influence of the polymerization distance of monowave and polywave light curing units (LCUs) on the measured irradiance relative to the value reported by the manufacturer in relation to the physical properties of resin-based composites (RBCs).

Methods: Four LCUs were used: one monowave and three polywave. The irradiance was measured with a digital radiometer. Depth of cure (DC) and flexural strength (FS) tests were performed according to ISO 4049:2019 at polymerization distances of 0 mm and 5 mm.

Results: The irradiance of all LCUs was higher than that reported by the manufacturer (>25-64%). The irradiance of the four LCUs was reduced when polymerization was performed at between 0 to 5 mm (paired t-test, P < 0.001). The DC at 0 mm was similar in all groups but was significantly decreased at 5 mm distance (ANOVA P < 0.001). FS showed differences among the LCUs at 0 mm (ANOVA P < 0.001) and was affected by the polymerization distance. The elastic modulus was unaffected by the LCU used or the distance (ANOVA P > 0.001).

Conclusions: The LCU must be positioned as near as possible to RBCs during the polymerization process, as increased distance negatively affects the depth of cure and flexural strength.

Purpose: To investigate the influence of various nickel-titanium (Ni-Ti) files on debris extrusion during the retreatment of teeth with simulated lateral root perforation, focusing on root resorption.

Methods: Sixty human mandibular premolar teeth were divided into groups with and without perforation and further subdivided based on the retreatment technique. Lateral root perforations were created in one group (Group 1), while the other group had no perforations (Group 2). Two retreatment techniques were compared: Remover (RE)+One RECI (OR) and ProTaper Universal Retreatment (PTUR)+WaveOne Gold (WOG). The weight of the extruded debris was determined. The time of both retreatment procedures was measured. Statistical analyses were performed using a two-way analysis of variance (ANOVA) test (P < 0.05).

Results: Teeth with simulated lateral root perforation exhibited higher extrusion of debris during retreatment. In both groups, RE+OR files led to more extruded debris than PTUR+WOG files. However, this difference was statistically significant in Group 2 (P < 0.001). Compared to PTUR+WOG files, RE+OR files showed a statistically significant longer time to remove obturation material (P < 0.001).

Conclusion: Perforated teeth exhibited significantly higher debris extrusion. While both file systems demonstrated similar debris extrusion in perforated teeth, the RE+OR files significantly increased debris extrusion in non-perforated teeth compared to the PTUR+WOG files.

Characterization of materials used in dental restorations and fixed prostheses is useful for personal identification. This study investigated the dental treatment trends and use of metal materials among non-Japanese Asian temporary residents and Japanese individuals aged from 20 to 40 years living in a city in Japan. Analysis of 38 participants from different Asian countries showed prominent use of resin fillings, with metal element analysis revealing nickel-chromium (Ni-Cr) or cobalt-chromium (Co-Cr) alloys. Among five Japanese participants of the same age with dental metal treatment scars, resin fillings and silver-palladium-copper-gold (Ag-Pd-Cu-Au) or silver-indium (Ag-In) alloys were observed. This study suggested some regional differences in dental material choices in Asia.

Purpose: Using X-ray micro-computed tomography (micro-CT), the aim of this study was to measure the porosity of two tricalcium silicate sealers (EndoSequence BC and NeoSealer Flo) applied using three obturation techniques (single-cone, warm-vertical, and cold-lateral) to six single-rooted human teeth.

Methods: Six extracted, single-rooted human teeth were shaped with ProTaper Next rotary files and obturated with EndoSequence BC or NeoSealer Flo sealers and gutta-percha (GP) using one of the three techniques above. Micro-CT was used to map the full length of the canals. Deep learning cross-sectional segmentation was used to analyze image slices of the apical (0-2 mm) and coronal (14-16 mm from the apex) regions (n = 230-261 per tooth) for the areas of GP and sealer, as well as porosity. Median (%) with interquartile range of porosity were calculated , and the results were statistically analyzed with the Kruskal-Wallis test.

Results: In the apical region, EndoSequence BC had significantly fewer pores than NeoSealer Flo with the single-cone obturation (% median-interquartile range, IQR: 0.00-1.62) and warm-vertical condensation (5.57-10.32) techniques, whereas in the coronal region, NeoSealer Flo had significantly fewer pores than EndoSequence BC with these two techniques (0.39-5.02) and (0.10-0.19), respectively. There was no significant difference in porosity between the two sealers for the cold-lateral condensation technique in both the apical and coronal regions.

Conclusion: For optimal obturation, the choice of technique and sealer is critical.

Purpose: Nausea and vomiting during pregnancy (NVP) are common among pregnant women and can be severe enough to require hospitalization. However, the mechanism underlying NVP pathogenesis remains unclear. This study examined factors associated with adverse events after vaccination, including a past history of NVP.

Methods: A questionnaire-based survey was completed by non-pregnant women working at Nagasaki University Hospital who received two doses of the BNT162b2 coronavirus disease 2019 (COVID-19) vaccine. This study primarily examined the association between a past history of NVP and post-vaccination fever, as fever was determined to be the most objective and reliable indicator of the surveyed adverse events.

Results: Multivariate logistic regression analysis showed that post-vaccination fever was more strongly associated with a past history of NVP (odds ratio, 1.88; 95% confidence interval, 1.16-3.07) than either age (0.73; 0.56-0.96) or weight (0.85; 0.70-1.15), which were previously considered to be highly associated with the incidence of adverse events following COVID-19 vaccination.

Conclusion: These results suggest an involvement of a similar pathological condition in developing NVP and post-vaccination fever.

The present work reports a case of a female patient complaining of itching and painful lesions affecting the oral mucosa for 7 months. Buccal and lip mucosa showed swelling and erythema, with serpiginous tracks. The patient was diagnosed with oral larva migrans, and the lesions resolved after ivermectin administration. At 18-month follow-up, no sign of recurrence was observed. Larva migrans can represent a pitfall in oral diagnosis and a stressful condition for the patient. Oral health care providers should be aware of this and keep this disease in mind as a possible differential diagnosis in oral mucosa lesions.

Purpose: This study explored the relationship between central sensitization symptoms, assessed using the Central Sensitization Inventory (CSI), and psychophysical factors in patients with chronic masticatory myofascial pain (MMP) transitioning from the acute to chronic stages.

Methods: In this study, 23 patients with MMP and 22 healthy volunteers were assessed using psychophysical tests, including measurements of pressure pain threshold (PPT) and temporal summation of pain (TSP). Additionally, CSI scores were recorded to evaluate central sensitization symptoms.

Results: Patients with chronic MMP showed significantly lower PPT in all masticatory muscles and extratrigeminal areas compared with controls. However, there was no significant correlation between CSI scores and psychophysical test results in patients with MMP.

Conclusion: The significant enhancement of TSP in patients with subchronic MMP suggests a potential role in the onset of myofascial pain. The main finding suggests that sub-chronic symptom patients show higher CSI scores despite no sensory testing changes, indicating that central sensitization possibly precedes observable symptoms.

This study aimed to clarify the usefulness of masticatory score by occlusal support. A total of 605 adults were classified into four groups (A1, A2A3, B, and C) according to the Eichner classification, and the relationship between the amount of glucose eluted and masticatory score was investigated in each group. A significant correlation between the glucose eluted and masticatory score was observed in groups A2A3, B, and C, but not in A1, suggesting that the masticatory score is useful for evaluating the masticatory performance of complete denture wearers, but not adults with natural dentition.

Purpose: This study was conducted to investigate the dental and palatal arch dimensions of male and female siblings in relation to gender and age, using three-dimensional (3D) digital casts.

Methods: This study involved 54 subjects (27 pairs) of male-female siblings aged 15 to 45 years. Dental casts were digitized and analyzed for tooth size (TS), arch width (AW), arch length (AL), arch length discrepancy (ALD), and palatal arch dimensions (PAD). The data obtained were subjected to t-tests, and the palatal curvature (PC) was modeled using a fourth-order polynomial.

Results: Significant differences (P < 0.05) between the sexes were found in the mesiodistal TS, particularly in all canines, as well as 16, 36, 46, and 41. Maxillary AW and AL were also significantly (P < 0.05) influenced by sexes. Most arch parameters were more prominent in male siblings, and the effect of age on PC differed between the sexes. In addition, the PC of adolescent females was mostly superimposed on adult females relative to males.

Conclusion: Among siblings, males were found to have significantly larger dental arch dimensions than females. Furthermore, PC showed some differences between the sexes in both the frontal and sagittal planes.

Purpose: This study analyzed associations of cumulative learning, demographic characteristics, fluoride content, and toothbrush head size with the amount of toothpaste used by dental students.

Methods: Students in the third and fifth year of dental school were recruited. Each participant was asked to dispense three toothpastes (pediatric, regular fluoride, and high fluoride) on five toothbrushes (rotation-oscillation, sonic, manual pediatric, and two manual adult toothbrushes). The length and weight of the toothpaste dispensed were recorded. The data were evaluated by nonparametric correlation analysis (P < 0.05).

Results: Eighty-one students (third year = 42; fifth year = 39; mean age: 26.2 ± 5.3 years) participated in the study. More toothpaste was dispensed by third-year students than by fifth-year students (weight: P = 0.014; length: P = 0.037). Men dispensed more toothpaste than did women (weight: P < 0.001; length: P = 0.042). Participants with higher educational attainment dispensed less toothpaste (weight: P < 0.001; length: P < 0.001). The type of toothbrush was associated with the weight of toothpaste dispensed (P < 0.001). Toothbrush head size was inversely associated with the length of toothpaste dispensed (P < 0.001).

Conclusion: The amount of toothpaste used by dental students was associated with cumulative learning, educational attainment, sex, and toothbrush head size but not with the fluoride content of the toothpaste.