Mahidol Dental Journal

A multidisciplinary approach for esthetic improvement in a patient with swimmer’s dental erosion: a 5-year recall case report

2024-07-23T07:50:52+07:00

This study showcases a multidisciplinary digital approach for esthetic improvement in a patient with swimmer’s dental erosion, particularly focusing on a predictable workflow of surgical crown lengthening and restoration in cases of gummy smiles and upper anterior teeth erosion. The patient presented with excessive gingival display and swimmer’s erosion in the upper anterior teeth. Utilizing computer-aided design/computer-aided manufacturing (CAD/CAM) systems, a final digital outcome design was generated, serving as a diagnostic wax-up model for this patient. The determined position of the gingival margin level and the contour of the digital final restoration design information were transferred to produce a reference surgical guide for the surgical crown lengthening process. Additionally, the digital design model facilitated the fabrication of a silicone index for the direct restoration procedure. The combination of a simple direct restoration technique and surgical crown lengthening, enabled by the digital multidisciplinary approach, effectively addressed the patient’s concerns.

A decellularized extracellular matrix hydrogel to promote the proliferation of human salivary gland cells

2024-08-13T08:20:02+07:00

Objectives: Matrigel, a raw matrix from the Engelbreth-Holm-Swarm mouse sarcoma, has been commonly used to promote salivary gland (SG) cell assembly and proliferation in vitro, however, it possesses limitations such as batch-to-batch variations and undefined tumor-derived components, hence, alternative matrices are lacking. This study aimed to develop porcine submandibular gland decellularized extracellular matrix (SG-dECM) hydrogels to support SG cell viability and proliferation.

Materials and methods: SG-dECM was produced using non-ionic and ionic detergent perfusions, then digested with a pepsin-based HCl buffer to generate SG-dECM hydrogels at concentrations of 1, 5, and 10 mg/mL. SG-dECM sections were stained with hematoxylin and eosin (H&E), and rhodamine-labeled peanut agglutinin staining of glycoproteins/mucins. A human submandibular gland cell line, A253 (HTB-41^TM, ATCC), was cultured as a monolayer culture with SG-dECM hydrogel- or Matrigel-coated on 96-well plates and assessed for proliferation over 4 days using an ATP-dependent assay. Uncoated wells were used as negative controls. Viable and late apoptotic cells were quantified with calcein-AM and propidium iodide staining, respectively. One- and two-way ANOVA with Tukey’s post-hoc tests were performed with 5 biological replicates.

Results: The developed SG-dECM retained moderately glycoproteins and mucins while cellular components were effectively removed. SG-dECM hydrogels at 5 mg/mL significantly enhanced A253 cell proliferation and viability compared to Matrigel (p<0.05) and uncoated wells (p<0.001) after 4 culture days.

Conclusion: SG-dECM hydrogels at 5 mg/mL promoted the proliferation and viability of A253 cells over 4 culture days. Thus, SG-dECM hydrogel could be a viable alternative to Matrigel for future drug screening applications.

Effect of saliva exposure time on the abrasion resistance of enamel eroded by acidic chlorinated water

2024-08-07T15:54:09+07:00

Objectives: To evaluate saliva exposure time on the abrasion resistance of enamel eroded by acidic chlorinated water

Materials and Methods: This experimental study used forty human premolars. The specimens were exposed to acidic chlorinated water and randomly assigned into 4 groups (n=10): Group-1; 0-minute saliva immersion and brushed (0MinImmBr); Group-2; 15-minutes saliva immersion and brushed (15MinImmBr); Group-3; 30-minutes saliva immersion and brushed (30MinImmBr); and Group-4; 60-minutes saliva immersion and brushed (60MinImmBr). Each group was evaluated using a Knoop hardness tester at baseline, post-erosion, post-saliva immersion, and post-toothbrushing. The length of each indentation obtained from the Knoop hardness testing was used to calculate the depth of the indentation and to determine surface enamel loss. One-way repeated ANOVA, One-way ANOVA, and LSD multiple comparison tests were used and the significance level was set at 0.05.

Results: The 60MinImmBr group demonstrated the significantly highest Knoop microhardness values among the post-saliva immersion and post-tooth brushing procedures. Statistical analysis revealed no significant difference in surface microhardness after these two procedures (p<0.05) in the 60MinImmBr group. In contrast, in the other 3 groups, the surface microhardness before and after toothbrushing was significantly different. The mean surface enamel loss was significantly lowest in the 60MinImmBr group compared with the other groups. The mean surface enamel loss between the 0MinImmBr and 15MinImmBr groups was not significantly different (p<0.05), however, it was significantly higher compared with the 30MinImmBr and 60MinImmBr groups.

Conclusions: The abrasion resistance of eroded enamel caused by acidic chlorinated water increased over time and at least 60 min should elapse before tooth brushing.

Association of religious and socio-cultural factors on dental service utilization among the elderly in Narathiwat, Thailand.

2024-09-13T10:35:07+07:00

Objective: The objective is to explore the association between religious and socio-cultural factors on dental service uses of elderly.

Materials and Methods: This observational study used retrospective dental treatment data from public dental health services in Narathiwat Province collected from July to December 2022 to identify eligible elderly patients. All of the elderly patients with an ADL Barthel score of 12 or higher were recruited to participate in the study. Then, face-to-face interviews were conducted using questionnaires adapted from Penchansky and Thomas's framework on health-service accessibility. The analysis included descriptive statistics and chi-square tests.

Results: A total of 106 elderly participated in the study. Most participants were female, aged 60-69, Muslims, and 47% had no formal education. Muslim-elderly-participants were more likely than Buddhists to report conflicts between dental procedures and religious principles. Additionally, 72.2% of Muslim elderly experienced difficulties in accessing services due to language barriers.

Conclusion: The study highlighted the significant association of socio-cultural factors on dental service utilization among the elderly in Thailand's southern border provinces. These findings emphasized the need for culturally sensitive public health policies, incorporating cultural awareness and language proficiency, to improve healthcare accessibility.

The effect of different concentrations of radiopacifier agents on the radiopacity level of nano-calcium hydroxide intracanal medication

2024-10-19T17:19:00+07:00

Objective: To assess radiopacity among nano-calcium hydroxide without and with the addition of various concentrations of barium sulfate as a radiopacifier.

Materials and Methods: The radiopacity of six materials: nano-calcium hydroxide, nano-calcium hydroxide with 25%, 30%, 35%, and 40% by weight of barium sulfate, and Ultracal XS® were evaluated according to ISO 6876:2012, with 5 specimens per group. Nano-calcium hydroxide and the various percentages by weight of barium sulfate were combined using a blending machine, then mixed with distilled water with a ratio of 1 g per ml. All samples were placed in the acrylic mold which was positioned alongside 0.5-mm increment aluminium step wedge and irradiated with x-ray 60 kV, 8 mA, for 0.2 seconds on a digital receptor. The radiopacity
of the materials was compared with the aluminium step wedge using the ImageJ program and transformed into mm of Al.

Results: The radiopacity of nano-calcium hydroxide ranged from 0.675 to 2.642 mmAl. The group without a radiopacifier exhibited the lowest radiopacity, followed by the groups with 25%, 30%, and 35% by weight of barium sulfate, while the highest radiopacity was observed in the group with 40% by weight of barium sulfate. Increasing the concentration of barium sulfate in nano-calcium hydroxide resulted in a proportional increase in radiopacity. Ultracal XS® showed lower radiopacity compared to nano-calcium hydroxide with 30% by weight of barium sulfate. Statistically significant differences in radiopacity were observed among all examined materials.

Conclusion: The radiopacity of nano-calcium hydroxide increases with the addition of barium sulfate. Approximately 30% by weight of BaSO4 should be added to achieve a radiopacity greater than 2 mmAl, based on an adaptation of the recommendation from the American National Standards Institute and the American Dental Association.

Effectiveness of passive ultrasonic irrigation and XP-endo Finisher in removing calcium hydroxide with different vehicles.

2024-09-30T07:48:52+07:00

Objective: The aim of this study was to compare the efficacy of passive ultrasonic irrigation (PUI) and the XP-endo Finisher (XPF) in removing calcium hydroxide (CH) residues from root canal walls across four different formulations.

Materials and Methods: Ninety mandibular premolar teeth were used in this study. After accessing the pulp chamber, root canals were prepared using the WaveOne® Gold system up to size 45. The specimens were randomly divided into four experimental groups (n=22): CH powder mixed with distilled water (CP), Ultracal™ XS (UC) representing aqueous-based CH, Metapaste® (MP) representing viscous-based CH, and Vitapex® (VP) representing oil-based CH. Within each group, two teeth were designated as positive controls, and the remaining 20 teeth were further subdivided based on the irrigation technique (PUI and XPF). Scanning electron microscope (SEM) analysis was used to evaluate the efficacy of each method in removing CH residues at the apical level, with statistical analysis conducted using two-way ANOVA with Bonferroni post hoc test.

Results: Cleaning efficacy was significantly affected by the type of medication (p<0.001), with VP showing the highest amount of remaining CH residue in both irrigation techniques. The percentages of remaining CH were as follows: CP-20.11%, UC-27.69%, MP-30.97%, and VP-55.37% in the PUI group, and CP-31.46%, UC-27.43%, MP-34.33%, and VP-59.37% in the XPF group, with statistical significance.

Conclusions: At the apical level, PUI and XPF are comparably effective in removing CH. The vehicle used to prepare CH is the most important factor affecting its removal. CP, UC, and MP showed similar removal efficacy, while VP was notably more challenging to remove at the apical level.