Mahidol Dental Journal

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

Apinya Witchutanonth, Woranun Prapansilp, Praphasri Rirattanapong — Wed, 16 Oct 2024 00:00:00 +0700

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.

Fri, 18 Oct 2024 00:00:00 +0700

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.

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

Mon, 14 Oct 2024 00:00:00 +0700

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.

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

Apinya Limvisitsakul, Watcharaporn Kuphasuk — Mon, 14 Oct 2024 00:00:00 +0700

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.