Effect of orodispersible hyaluronic acid film on palatal mucosa wound healing.

OBJECTIVE: The objective of the study was to evaluate the healing effect of hyaluronic acid films on palatal wounds. MATERIALS AND METHODS: After making 5-mm diameter palatal wounds, 72 rats were randomly assigned to three groups: control, hyaluronic acid gel, and hyaluronic acid film. The animals were sacrificed at 3, 7, and 21 days after the experiment. Clinical, histological, and RT-PCR analyses were performed. Human ex vivo oral mucosa models were used. Histological analysis and pan-cytokeratin staining were performed at 5 days after wound creation. RESULTS: In rat model, both gels and films showed favorable healing on Days 3 and 7 compared with healing in the control (p < 0.05). Film showed remarkable VEGF and α-SMA expression than did the others (p < 0.05). Immunohistochemical analysis showed that film exhibited significantly lower CD68 and greater α-SMA and vimentin expression levels than those in the others (p < 0.05). In human model, re-epithelialization rate of film group was significantly higher than that of the others. Complete epithelial regeneration was confirmed only in film group using pan-cytokeratin staining. CONCLUSIONS: Within the limits of this study, hyaluronic acid film outperformed gels in terms of palatal wound healing in both models.

Effect of intra-alveolar delivery of Frondoside A on inflammatory response of delayed tooth replantation.

BACKGROUND/AIM: Frondoside A is a sea cucumber extract which is well known for its anti-inflammatory and immunomodulatory properties. The purpose of this study was to evaluate the effect of Frondoside A application in the alveolar socket on inflammatory responses after delayed replantation in rat teeth. MATERIALS AND METHODS: Human periodontal ligament cells were cultured and exposed to Frondoside A. Cell-counting kit-8 assay was performed to evaluate the cell viability and nitric oxide assay was performed to assess the anti-inflammatory effect of Frondoside A. Molars were extracted from 32 Sprague-Dawley rats and randomly divided into control and Frondoside A groups. After 30 min of extra-oral dry time, molars were replanted. In the Frondoside A group, Frondoside A solution was applied in the alveolar socket before replantation. The animals were sacrificed after 28 days and histologically and immunohistochemically evaluated. RESULTS: 0.5 µM Frondoside A showed higher cellular viability at 6 h and lower production of nitric oxide compared with other Frondoside A solutions (p < .05). The Frondoside A group demonstrated lower inflammatory resorption scores in both middle 1/3 and apical 1/3 of root compared to the control group (p < .05). The Frondoside A group showed lower levels of expression in both cathepsin K and CD45 compared with the control group (p < .05). CONCLUSIONS: Within the limits of this study, intra-alveolar delivery of Frondoside A alleviates inflammatory root resorption in delayed replantation of rat teeth.

Influence of limited mouth opening in children on intraoral scanning accuracy: An in vitro study.

BACKGROUND: Although intraoral scanning is highly reliable, little is known about its accuracy in young children with limited mouth-opening ability. AIM: To determine the accuracy of intraoral scans based on the degree of mouth opening. DESIGN: To simulate mouth opening in children with primary dentition, three groups (n = 5 per group) were allocated by maximum mouth opening of 30, 37 and 40 mm. After the primary dentition model was connected to a dental phantom, intraoral scanning was performed using iTero and TRIOS4. The scanned files were digitally evaluated. Root mean square values were calculated to assess trueness and precision. RESULTS: iTero showed deviations of three-dimensional trueness of 0.067 ± 0.008, 0.063 ± 0.001 and 0.065 ± 0.005 mm, and TRIOS4 of 0.07 ± 0.002, 0.064 ± 0.003 and 0.066 ± 0.002 mm in the 30, 37 and 40 mm groups, respectively. There were no significant differences in either mouth opening (p > .017) or the intraoral scanners (p > .05). The same statistical results were obtained for precision, with the exception of the 30 mm of mouth opening. CONCLUSIONS: Within the limits of this study, limited mouth opening hardly influenced the accuracy of intraoral scanning.

Nonalcoholic Fatty Liver Disease Without Metabolic-associated Fatty Liver Disease and the Risk of Metabolic Syndrome.

BACKGROUND & AIMS: Metabolic (dysfunction)-associated fatty liver disease (MAFLD) was proposed to replace nonalcoholic fatty liver disease (NAFLD). Some people fulfill diagnostic criteria of NAFLD but not MAFLD (NAFLD without MAFLD), but the clinical implications of NAFLD in these subjects is unknown. METHODS: We followed cohort of 12,197 men and women 20 years of age or older without metabolic dysfunction (defined by MAFLD criteria), heavy alcohol use, chronic viral hepatitis, liver cirrhosis, or malignancy for their risk of incident metabolic syndrome defined by Adult Treatment Panel III criteria. RESULTS: By design, none of the study participants had MAFLD at baseline. The prevalence of NAFLD among participants without metabolic dysfunction meeting MAFLD criteria and without significant alcohol intake was 7.6%. During 74,508 person-years of follow-up, 2179 participants developed metabolic syndrome. The fully adjusted hazard ratio for metabolic syndrome comparing participants with NAFLD to those without it was 1.61 (95% confidence interval, 1.42-1.83). The increased risk of incident metabolic syndrome associated with NAFLD persisted for all studied subgroups, and the association was stronger for those with increased waist circumference (P for interaction = .029) and those without elevated triglycerides levels (P for interaction = .047). CONCLUSION: In this large cohort, participants with NAFLD without MAFLD were at higher risk of developing metabolic syndrome compared to participants with no NAFLD and no MAFLD. Using MAFLD criteria may miss opportunities for early intervention in these subjects.

Interval Advanced Gastric Cancer After Negative Endoscopy.

BACKGROUND & AIMS: Esophagogastroduodenoscopy (EGD) is effective in reducing gastric cancer mortality through detection of early-stage cancer in areas with a high prevalence of gastric cancer. Although the risk of post-endoscopy advanced gastric cancer (AGC) is low, interval AGC remains a concern. We investigated the characteristics and predictors of interval AGC after negative EGD. METHODS: We included 1257 patients with gastric cancer within 6 to 36 months of a "cancer-negative" index EGD between 2005 and 2021 at a tertiary university hospital in South Korea. Observation time on the index EGD was used as a quality indicator. We compared the clinical and endoscopic characteristics and quality indicators between interval AGC and screen-detected early gastric cancer (EGC). RESULTS: Within 6 to 36 months of negative EGD, 102 AGCs (8.1%) and 1155 EGCs (91.9%) were identified. The percentage of patients with shorter observation time (<3 minutes) in the index EGD was higher in the interval AGC group than in the detected EGC group (P = .002). A multivariable analysis comparing screen-detected EGD and interval AGC was adjusted for age, sex, family history of gastric cancer, H. pylori status, endoscopic findings, and endoscopy-related factors including gastric observation time and interval time. A shorter observation time (<3 minutes) (odds ratio, 2.27; 95% confidence interval, 1.20-4.30), and interval time >2 years (odds ratio, 1.84; 95% confidence interval, 1.04-3.24) were associated with an increased risk of interval AGC. CONCLUSION: A shorter observation time during index EGD is an important predictor of interval AGC. Further, withdrawal time longer than 3 minutes may be a quality indicator for screening EGD.

Evaluation of delphinidin as a storage medium for avulsed teeth.

BACKGROUND: Delphinidin (DP), an anthocyanidin found in blueberries, has antioxidant and anti-inflammatory effects. This study aimed to investigate the efficacy of DP as a storage medium for avulsed teeth. METHODS: Human periodontal ligament cells were cultured and exposed to DP solution (10, 50, and 100 µM), Dulbecco's modified Eagle's medium, Hank's balanced salt solution and tap water. Cell counting kit-8 assays were performed after 0.5, 1, 6, and 24 h to measure the cell viability. Nitric oxide assays and gelatin zymography were performed to evaluate the anti-inflammatory effects of DP. Reverse transcription-polymerase chain reaction was used to determine the expression levels of inflammatory cytokines. RESULTS: The viability of periodontal ligament cells was greatest at 100 µM DP. At 1 h, 100 µM DP decreased nitric oxide synthesis (p < .0167). Matrix metallopeptidase-9 activity was inhibited by DP in a dose-dependent manner (p < .0167). Moreover, treatment with 100 µM DP decreased the expression levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 in periodontal ligament cells (p < .0167). CONCLUSIONS: Within the limits of this study, DP preserved the viability and suppressed the inflammatory response of periodontal ligament cells. These findings suggest that DP could be promising for preservation of avulsed teeth.

Determination of the range of intervention timing for supernumerary teeth using the Korean health insurance review and assessment service database.

This study aimed to identify the frequency of complications during the diagnosis, observation, and treatment of supernumerary teeth or odontomas and evaluate the relationship between complications and the timing of surgical intervention. This study was conducted based on data from the Korea Health Insurance Review and Assessment Service between January 2008 and December 2019. A 2-year washout period was applied, and a follow-up period of at least 2 years was also included. During the observation period, the age at diagnosis of supernumerary teeth and odontomas was analyzed using major diagnostic codes, and the treatment codes were used to determine the interval between diagnosis and surgical intervention. The incidence rates of supernumerary teeth (1.21%) and odontomas (0.36%) were comparable to that reported in previous studies. The frequency of supernumerary teeth was the highest in the anterior region, followed by the premolar and molar regions. The average ages at diagnosis according to the location of the supernumerary teeth were 7.25, 13.98, and 16.11 years in the anterior, premolar, and molar regions, respectively. The age at diagnosis correlated with the maturity period of the teeth at the corresponding location. For the supernumerary tooth group, surgical intervention was more likely to occur when malocclusion (p < 0.0001) or tooth eruption disturbances (p < 0.0001) were present or dentigerous cysts were absent (p = 0.006). For the odontoma group, malocclusion (p = 0.251) was not correlated with surgical intervention. When tooth eruption disturbances (p = 0.002) and dentigerous cysts (p < 0.0001) were present, surgical intervention was more likely to occur. Pediatric dentists should conduct timely clinical checks and periodic follow-ups to prevent complications and unnecessary orthodontic treatments in patients with supernumerary teeth or odontomas.

Bisphenol A release from commercially available 3-dimensionally printed resins and human cell apoptosis to bisphenol A: an in-vitro study.

Bisphenol A (BPA) from dental materials may be linked to children's health issues. This study aimed to assess the release of BPA from commercially available 3-dimensional (3D)-printed resin materials and evaluate BPA-related apoptotic effects on human periodontal ligament cells and gingival fibroblasts. Commercially available 3D-printed resin materials for prosthodontic use were selected as follows: NextDent C&B MFH (3D Systems, Rock Hill, SC, USA), DIOnavi-P. MAX (Dio Co., Busan, Korea), and DIOnavi-Denture02 (Dio Co., Busan, Korea). Identical cuboidal samples (1 cm × 1 cm × 0.5 cm) were printed from the materials and cured. BPA release was assessed using liquid chromatography/mass spectrometry (LC/MS). In addition, human gingival fibroblasts and periodontal ligament cells were exposed to various BPA solutions based on the LC/MS results. Cell Counting kit-8 (CCK-8) and real-time polymerase chain reaction analyses were performed to evaluate BPA-related apoptotic effects. The LC/MS analysis confirmed that none of the 3D-printed resin materials released BPA after curing. Both human gingival fibroblasts and periodontal ligament cells showed lower viability after BPA exposure. Regarding apoptosis-related gene expression, Caspase10 (CASP10) expression in periodontal ligament cells was significantly different in the BPA solutions (p < 0.05). The expression of BAX and Capspase8 (CASP8) in gingival fibroblasts was significantly increased by BPA in a dose-dependent manner (p < 0.05). Within the limitations of this study, the 3D-printed resin materials were not found to release BPA. This finding implies that 3D-printed resin materials are not associated with potential BPA-related risks in children.

Three-dimensional evaluation of tooth preparation forms in paediatric zirconia crowns: An in vitro study.

BACKGROUND: Though prefabricated zirconia crowns (PZCs) differ from stainless steel crowns and have different preparation guidelines for optimal crown adaptation, little is known about how clinicians prepare teeth for PZCs. AIM: To investigate the prepared tooth forms for PZCs and identify the shared patterns of tooth preparation. DESIGN: Twenty participants prepared primary maxillary first molars and mandibular second molars for PZCs. A model with ideally prepared tooth was digitally generated as a reference. The prepared teeth were digitally scanned and superimposed on the reference. Three-dimensional analysis software was used to evaluate the discrepancy between ideal and prepared surface for overall surface and subdivided area. RESULTS: Half of the surfaces received excessive reduction, and 24% showed error within 0.2 mm (p < .001) in maxilla. 41.6% of surfaces showed error within 0.2 mm, and 20% were excessively prepared (p = .002) in mandible. The highest discrepancies were found at the mesiopalatal line angles (maxillary) and at the distobuccal line angles (mandibular). Significant discrepancies were observed on the occlusal surfaces, especially at the cusps. CONCLUSIONS: Tooth preparations for PZCs showed wide variations related to depth among the participants.

Stress distribution in pediatric zirconia crowns depending on different tooth preparation and cement type: a finite element analysis.

BACKGROUND: In clinical settings, tooth preparation for prefabricated zirconia crowns (PZCs) in the primary dentition varies widely. However, knowledge about the biomechanical behavior of PZCs in various clinical settings is limited. This study was conducted to evaluate the biomechanical behavior of PZCs in different clinical settings using 3-dimensional finite element analysis. METHODS: 3-dimensional models of the PZC, cement, and tooth with six different conditions were simulated in primary molar teeth, incorporating cement thickness (100, 500, and 1000 µm) and cement type (resin-modified glass ionomer cement and resin cement). A total of 200 N of occlusal force was applied to the models, both vertically and obliquely as representative cases. A general linear model univariate analysis with partial eta-squared (ηp2) was performed to evaluate the relative effects of the variables. RESULTS: The overall stress of tooth was increased as the cement space increases under oblique loading. The von Mises stress values of the resin cements were significantly higher than those of the resin-modified glass ionomer cements for all cement thicknesses (p < .05). The effect size of the cement type (ηp2 = .519) was more dominant than the cement thickness (ηp2 = .132) in the cement layer. CONCLUSIONS: Within the limits of this study, cement type has a greater influence on the biomechanical behavior of PZCs than cement thickness.

Proton pump inhibitors use and the risk of fatty liver disease: A nationwide cohort study.

BACKGROUND AND AIM: Proton pump inhibitor (PPI)-induced hypochondria can change the composition of the gut microbiota, inducing overgrowth of small bowel bacteria, which has been suggested to promote the development of fatty liver disease through the gut-liver axis. In this study, we aimed to investigate the association between PPI use and the risk of fatty liver disease. METHODS: A retrospective cohort study was conducted using the Korean National Health Insurance Service-National Sample Cohort, a nationwide population-based representative sample, from January 1, 2002, to December 31, 2015. PPI use was identified from treatment claims and considered as a time-varying variable. RESULTS: During 1 463 556 person-years of follow-up, 75 727 patients had at least one PPI prescription, and 3735 patients developed fatty liver disease. The hazard ratio for fatty liver disease comparing PPI users with non-PPI users was 1.68 (95% confidence interval, 1.61-1.75). When adjusted for multiple confounders, including age, sex, body mass index, smoking, alcohol intake, exercise, income level, and comorbidities, the association was still significant (hazard ratio, 1.50; 95% confidence interval, 1.44-1.57). After considering the amounts of PPIs stratified by cumulative defined daily dose, the dose-response effect was observed until 180 days. Subgroup analysis also revealed that PPI use was correlated to an increased risk of fatty liver disease. CONCLUSIONS: This current national wide cohort study suggests that PPI use was associated with an increased risk of fatty liver disease compared with non-use of PPIs. Clinicians should consider fatty liver as a potential risk when prescribing PPI.

The perspective of undergraduate dental students on web-based learning in pediatric dentistry during the COVID-19 pandemic: a Korean multicenter cross-sectional survey.

BACKGROUND: The COVID-19 pandemic changed the world and created a shift in the dental education program. This sudden change in the dental education program may have affected the academic standards of dental students. This study aimed to evaluate the overall satisfaction and effectiveness of online learning in pediatric dentistry of undergraduate dental students' during the COVID-19 pandemic in South Korea. METHODS: An anonymous online survey was sent to three dental schools, and responses were collected from dental school students. Questions included the demographics, perspectives of online classes, comparison of online and offline pediatric dentistry classes and opinions on how dental schools are handling the pandemic. Students' perspectives on online classes were evaluated based on satisfaction with online education. Data were analyzed using the Kruskal-Wallis test and the Mann-Whitney U test. RESULTS: Most students took online classes from home (80.9%) using Zoom (50.4%). The majority reported overall program satisfaction (74.1%) and agreed that universities implemented online classes well (55%). Students who were in favor of online classes responded more positively to questions on the effectiveness and safety of online learning (p < 0.05). Regardless of satisfaction with online education, the students agreed that the online education shift was the right decision in pandemic outbreak. CONCLUSIONS: Dental students in South Korea preferred and adapted well to the web-based learning program in pediatric dentistry during COVID-19 pandemic.

Void characteristics and tortuosity of calcium silicate-based cements for regenerative endodontics: a micro-computed tomography analysis.

BACKGROUND: Internal voids of materials can serve a hub for microorganism and affect the sealing ability. This study aimed to evaluate the sealing performance of calcium silicate-based cements in immature teeth treated with regenerative endodontics. METHODS: Twenty single root canals from immature permanent premolars were prepared using regenerative endodontic protocols. The root canals were randomly divided into two groups and sealed with mineral trioxide aggregate (MTA) and Biodentine (BD). The teeth were kept in humid environment for 7 days and scanned using micro-computed tomography. The voids within the cements were segmented and visualized using image processing, incorporating the modified Otsu algorithm. The porosity of each sample was also calculated as the ratio between the number of voxels of voids and the volume of the cements. Tortuosity was also calculated using the A-star algorithm. RESULTS: Voids larger than 70 µm were predominantly observed in the top and interfacial surface of cements. The others were evenly distributed. MTA and BD showed the same level of porosity and tortuosity at interfacial surfaces. In inner surfaces, MTA showed more less porosity and tortuosity compared to BD (p < 0.05). CONCLUSIONS: There were no differences in sealing performance between MTA and BD.

Differential gene expression profiles of human periodontal ligament cells preserved in Hank's balanced salt solution and milk.

BACKGROUND/AIM: Various types of storage media have been investigated to preserve avulsed teeth. However, the efficacies of storage media mainly focus on the aspect of cell viability. The aim of this study was to evaluate and compare the gene expression profiles of human periodontal ligament cells preserved in Hank's balanced salt solution (HBSS) and milk over different storage durations. MATERIAL AND METHODS: Human periodontal ligament cells were cultured and preserved in HBSS and milk for 3 and 6 hours. Next, total RNA was isolated. QuantSeq 3' mRNA-Sequencing was used to examine differences in gene expression in HBSS- and milk-grown periodontal ligament cells. Bioinformatics analysis was also performed to predict the function of the differentially expressed genes. RESULTS: The number of differentially expressed genes shared among all groups was 101. In gene set enrichment analysis, the shared differentially expressed genes in HBSS and milk were associated with the TNF-α signaling pathway (P = 1.07E-7 ). Seven hallmark gene sets were also identified in HBSS. Moreover, hallmark gene sets associated with hypoxia (P = 7.26E-5 ) and apoptosis (P = 4.06E-4 ) were identified in HBSS. In milk, 10 hallmark gene sets along with gene sets for inflammatory response (P = 6.87E-3 ) were identified. CONCLUSIONS: Compared to those in milk, genes in HBSS were differentially expressed with increasing storage duration, suggesting that diverse and different gene expression may be involved in HBSS and milk. However, a more detailed functional analysis of these differentially expressed genes in storage solutions should be performed in the future.

Validation of a three-dimensional printed model for training of surgical extraction of supernumerary teeth.

INTRODUCTION: This study aimed to validate a three-dimensional (3D) printed model to provide training for supernumerary teeth (SNTs) extraction. MATERIALS AND METHODS: Each of the 30 participants, grouped as experienced and without experience, conducted two identically simulated surgeries on a 3D-printed replica of human mixed dentition with a SNT. The surgery time, area of bony window and volume of removed material were measured; subsequently, responses to a five-item questionnaire were recorded. The collected data were statistically analysed. RESULTS: The surgery time was 228.37 ± 141.53 seconds and 125.47 ± 53.03 seconds in the first and second surgery, respectively. The training significantly decreased the surgery time in the participants without experience (P = .000). However, there were no significant differences in the area of window opening (P = .271) and volume of removed material between the two surgeries (P = .075). The participants who perceived educational benefits accounted for more than 60% of the respondents for every question. Participants without experience in SNT extraction showed a tendency to rate a higher score than did those with experience. CONCLUSIONS: A 3D-printed model for surgical extraction of a SNT can improve surgical skill and, especially, shorten the learning curve in beginners.

Interdisciplinary Approach to Treat Unusual Development of Dens Evaginatus: A Case Report.

The present case report describes a rare case of dens evaginatus on the labial surface of mandibular incisor and interdisciplinary management including endodontic and periodontal treatment. A 10-year-old girl presented unusual whitish tubercle-like structure penetrated through the buccal gingiva of mandibular later incisor. In cone-beam computed tomographic view, pulpal tissue was extended from the principal root to the tubercle. Following full thickness flap reflection, the tubercle was carefully removed, resulting in dentin and pin-point pulp exposure. In order to prevent pulp necrosis and facilitate periodontal attachment to this area, Biodentine and enamel matrix derivative were applied. Gingival defect was compensated using a collagen matrix. Up to 2 years, harmonious gingiva state and no loss of tooth vitality were observed. In summary, dens evaginatus on mandibular later incisor could be successfully treated by means of interdisciplinary approach.

Three-Dimensional Digitalized Surface and Volumetric Analysis of Posterior Prefabricated Zirconia Crowns for Children.

Objectives: This study was designed to compare the surface morphologies and volumes of posterior prefabricated zirconia crowns and posterior stainless steel crowns (SSCs) using digitalized three-dimensional (3D) reconstructed images. Study design: We tested prefabricated zirconia crowns (NuSmile ZR; Orthodontic Technologies, Houston, TX, USA) and SSCs (Kids Crown; Shinhung, Seoul, Korea) used to restore left maxillary and mandibular molars. A Rainbow scanner (Dentium, Seoul, Korea) was used to digitise the inner and outer surface morphologies of all crowns. The data were superimposed and evaluated using 3D software. The differences between the outer and inner surfaces and inner volume were measured. Results: The differences between the two types of crowns differed by tooth surface. At the occlusal surface, the differences were greater at the cusp tip than the fossa. At the axial level, the differences decreased toward the gingival margins. Also, relative volumetric ratios varied. Conclusions: Tooth preparation prior to placement of prefabricated zirconia crowns requires special consideration. Greater amounts of tooth reduction are necessary for posterior zirconia crowns than for SSCs. The occlusal surface requires more tooth reduction than the axial surface and the gingival margin.

A retrospective study of traumatic dental injuries in primary dentition: treatment outcomes of splinting.

OBJECTIVE: Splinting in primary dentition is limited to several traumatic dental injuries. The prognosis associated with splint use has not been fully investigated. In this study, we investigated the outcomes of traumatic injuries in primary teeth treated with splinting. MATERIALS AND METHODS: We retrospectively analysed 137 children with root fractures and lateral and extrusive luxation injuries to their primary teeth who were treated with semi-rigid splints between 2010 and 2016. Treatment outcomes were analysed in patients with follow-up periods of >6 months. The outcomes of splinting were based on clinical and radiographic evaluations performed during follow-up examinations. RESULTS: In total, 182 primary teeth were examined, and of these, 90 teeth were treated using semi-rigid splints. In the splint group, pathological root resorption (31.1%) was the most common complication, whereas pathological tooth loss (25.0%) was found most common in the observation group. Splinting in root fractures showed a good prognosis, whereas in lateral and extrusive luxations, it did not (p < .05). There were no relationship between treatment delay and prognosis (p > .05). CONCLUSIONS: Depending on the type of luxation, splint therapy results in acceptable outcomes and may be a feasible treatment option.

Analysis of bacterial community profiles of endodontically infected primary teeth using pyrosequencing.

OBJECTIVE: The purpose of this study was to identify the endodontic microbiome in primary teeth with dental caries using high-throughput pyrosequencing and to establish data on the oral microbiome of primary teeth with endodontic infection. METHODS: Ten primary teeth with dental caries and endodontic infection were included. Samples were collected from root canals using sterilized paper points and analyzed by pyrosequencing, based on the V1-V3 hypervariable region of the 16S rRNA gene. The data were analyzed using the CLcommunity software. RESULTS: Analysis of the 10 samples yielded a total of 64,291 16S rRNA gene sequences. In total, 1586 OTUs (range, 91-235), six bacterial phyla, including unclassified, and 187 genera were assigned. At the genus level, Neisseria (group A), Acinetobacter (group B), and Fusobacterium (group C) were prominent. These predominant microorganisms were associated with the clinical condition and reflected the progression of endodontic infection in primary teeth. CONCLUSIONS: This study revealed a relationship between the oral microbiome and endodontic infection in primary teeth. Additionally, anaerobic bacteria such as Fusobacterium species were dominant in the teeth with apical abscesses.

Development of a Web-Based Nationwide Korean Pediatric Dental Sedation Registry.

OBJECTIVE: Finding a balance between sedation efficacy and safety remains an ongoing challenge. In children, the risk of sedation-related complications is relatively high. It is of utmost importance to determine the factors related to improved overall sedation outcomes. However, most previous reports have been based on small samples at single institutions. The Korean Academy of Pediatric Dentistry (KAPD) developed a Korean Pediatric Dental Sedation Registry using a web-based platform. STUDY DESIGN: Specialists in pediatric dental sedation selected the itemized list included within the registry through an extensive literature review. The web-based registry was built into the KAPD homepage to facilitate easy access to the sedation data. All teaching and university hospitals agreed to participate in the Korean Pediatric Dental Sedation Registry. CONCLUSION: This is the first attempt to collect sedation data on a nationwide scale in the field of pediatric dentistry. The sedation database established with the registry may facilitate standardizing and improving pediatric dental sedation clinical practices.