The purpose of this study was to determine whether convolutional neural networks (CNNs) can predict paresthesia of the inferior alveolar nerve using panoramic radiographic images before extraction of the mandibular third molar. The dataset consisted of a total of 300 preoperative panoramic radiographic images of patients who had planned mandibular third molar extraction. A total of 100 images taken of patients who had paresthesia after tooth extraction were classified as Group 1, and 200 images taken of patients without paresthesia were classified as Group 2. The dataset was randomly divided into a training and validation set (n = 150 [50%]), and a test set (n = 150 [50%]). CNNs of SSD300 and ResNet-18 were used for deep learning. The average accuracy, sensitivity, specificity, and area under the curve were 0.827, 0.84, 0.82, and 0.917, respectively. This study revealed that CNNs can assist in the prediction of paresthesia of the inferior alveolar nerve after third molar extraction using panoramic radiographic images.

Background: The aim of this study was to report a rare case of nasopalatine duct cyst with sebaceous differentiation. Further, a systematic search of the literature was performed to identify studies reporting patients with intraosseous jaw cysts with sebaceous differentiation. Case presentation: A 55-year-old Korean man was referred to our hospital because of a cystic lesion of the anterior maxilla. Radiologic examination revealed a well-circumscribed radiolucent lesion in the anterior maxilla. Histology showed a respiratory columnar and cuboidal epithelium-lined cyst. Transition from the ciliated columnar epithelium to stratified squamous epithelium with sebaceous differentiation was observed. Based on these findings, the final diagnosis was nasopalatine duct cyst with sebaceous differentiation. A systematic search of the literature was performed to identify studies reporting patients with intraosseous jaw cysts with sebaceous differentiation. There were 24 cases of sebaceous differentiation in the epithelium of the cysts including 2 odontogenic keratocysts, 8 orthokeratinized odontogenic cysts, 8 dentigerous cysts, 1 radicular cyst, and 2 glandular odontogenic cysts. However, no case reports describing the occurrence of nasopalatine duct cysts with sebaceous differentiation have been reported. Conclusion: This first case report of nasopalatine duct cysts with sebaceous differentiation could provide insight into the diagnostic process of cystic lesions with sebaceous differentiation.

In this study, we evaluated changes in the masseter and lateral pterygoid muscles in the prognathic mandible group after a mandibular setback by comparing the volume-to-length ratios. Preoperative and postoperative 1-year computed tomography was used to calculate the volume-to-length ratio of the lateral pterygoid and masseter muscle in 60 Korean individuals. Three-dimensional images were reconstructed, the results of which showed no significant differences in the volume-to-length ratios of the masseter and lateral pterygoid muscles after a mandibular setback (p > 0.05). This result was found for both vertical ramus osteotomy and sagittal split ramus osteotomy, and for both males and females. No significant differences in the volume-to-length ratio of the masseter and lateral pterygoid muscles were found up to 1 year after a mandibular setback. Therefore, this study can contribute to the prediction of soft-tissue profiles after mandibular setback.

Mandibular prognathism is one of the most concerning subjects in the oral and maxillofacial fields. In our previous studies, we attempted to clarify the etiology of mandibular prognathism. They revealed that one of the major characteristics of mandibular prognathism was the lower volume/length ratio of the mandibular condyle and body compared to normal, and the masseter muscle showed parallelism with this. This study aimed to evaluate the relationship between mandibular prognathism and the lateral pterygoid muscle by measuring the orientation and volume/length ratio of the lateral pterygoid muscle. Computed tomography was used to calculate the volume/length ratio of the lateral pterygoid muscle in 60 Korean individuals. Mimics 10.0 and Maya version 2018 were used to reconstruct the surface area and surface planes. The results showed that the prognathic group showed smaller lateral pterygoid volume/length ratios compared to the normal group (p < 0.05). In addition, the normal group displayed a larger horizontal angle (p < 0.05) to the mandibular and palatal planes than the prognathic group. This demonstrated that the mechanical drawback of the lateral pterygoid in the prognathic group is associated with mandibular prognathism.

The Pederson difficulty score (PDS) is widely used to assess mandibular third molar extraction difficulty, but is subject to interobserver variability because no universally accepted reference standard exists. This study investigates whether multimodal large language models (LLMs) demonstrate systematic grading tendencies comparable to those of human clinicians in the absence of a definitive standard. This retrospective cross-sectional study included 100 panoramic radiographs. Two LLMs (GPT and Gemini) and two oral and maxillofacial surgeons independently graded extraction difficulty using the PDS. No reference standard or gold-standard rater was designated; all raters were treated as independent assessors. Agreement was assessed using quadratic-weighted kappa and intraclass correlation coefficient values. Systematic bias was analysed using Bland-Altman plots and ordinal logistic regression. The effects of prompt language and session protocol were also evaluated. The interexpert agreement was substantial (κ = 0.754). GPT demonstrated moderate agreement with experts (κ = 0.564-0.590), whereas Gemini exhibited fair-to-moderate agreement (κ = 0.356-0.461). Overall, the four-rater reliability was moderate (intraclass correlation coefficient = 0.553). Both LLMs displayed minimal systematic bias (GPT: -0.13; Gemini: -0.08), with no significant differences in grading tendencies compared with human experts (P > .05). However, sequential-session evaluation significantly reduced the scoring consistency for both models (GPT: P = .001; Gemini: P < .001), whereas prompt language had no significant effect on total PDS scores (GPT: P = .543; Gemini: P = .386). A component-level linguistic variation was observed only in GPT's assessment of the ramus relationship (P = .003). The examined LLMs showed grading tendencies partly comparable to those of human clinicians, without evidence of systematic directional bias; however, agreement remained below interexpert levels and was sensitive to conversational context. These findings should not be interpreted as evidence of diagnostic accuracy or clinical reliability, as no reference standard was established. LLMs may provide supplementary grading information if used with independent-session protocols; however, their role in clinical decision-making requires further validation against defined outcome standards.

Cystic lesions in pediatric jaws can cause eruption disorders by displacing the erupting permanent teeth, and in the case of secondary infection, can cause swelling and pain. The treatment modalities for such cysts include cyst enucleation, marsupialization, and decompression. As compared to enucleation, decompression has the advantage of preventing damage to surrounding tissues and inducing spontaneous eruption of permanent teeth.We report a case where decompression was performed using a stent designed for decompression and as a space maintainer in three patients with eruption disorder due to cystic lesion of the jaw. The eruption of the displaced permanent teeth was successfully induced by maintaining the eruption space and removing the cyst.