• 반도체디스플레이기술학회지
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• 제20권1호
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• pp.70-76
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• 2021

A cylindrical microlens (CML) has been widely used as an optical element for organic light-emitting diodes (OLEDs), light diffusers, image sensors, 3D imaging, etc. To fabricate high-performance optoelectronic devices, the CML with high aspect ratio is demanded. In this work, we report on facile solution-based processes (i.e., slot-die and needle coatings) to fabricate the CML using poly(methyl methacrylate) (PMMA). It is found that compared with needle coating, slot-die coating provides the CML with lower aspect ratio due to the wide spread of solution along the hydrophilic head lip. Although needle coating provides the CML with high aspect ratio, it requires a high precision needle array module. To demonstrate that the aspect ratio of CML can be enhanced using slot-die coating, we have varied the molecular weight of PMMA. We can achieve the CML with higher aspect ratio using PMMA with lower molecular weight at a fixed viscosity because of the higher concentration of PMMA solute in the solution. We have also shown that the aspect ratio of CML can be further boosted by coating it repeatedly. With this scheme, we have fabricated the CML with the width of 252 ㎛ and the thickness of 5.95 ㎛ (aspect ratio=0.024). To visualize its light diffusion property, we have irradiated a laser beam to the CML and observed that the laser beam spreads widely in the vertical direction of the CML.

• Journal of Dental Anesthesia and Pain Medicine
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• 제21권2호
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• pp.129-137
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• 2021

Background: Inappropriate use of intravenous and inhaled anesthetics may be dangerous in infants undergoing facial cleft surgeries. This study primarily aimed to compare the effect of infraorbital nerve block on sevoflurane requirement in infants undergoing cheiloplasty. Intraoperative opioid consumption, hemodynamics, blood glucose levels, extubation time, and delirium were also compared. Methods: This prospective, randomized, double-blinded study was conducted in 34 infants undergoing cheiloplasty under general anesthesia. After induction, group A received bilateral infraorbital nerve block with 0.5 mL of 0.5% bupivacaine and group B 0.5 mL saline. An increase in heart rate or blood pressure > 20% was managed by increasing sevoflurane by 2-2.5%, followed by fentanyl 0.5 ㎍/kg bolus. The chi-square test and independent-sample t-test were used where applicable. Results: Demographics, duration of surgery, and intravenous fluids used were comparable between the groups. Compared to group A, patients in group B had significantly higher consumption of fentanyl (14.2 ± 4.4 ㎍ vs. 22.1 ± 6.2 ㎍) and sevoflurane (14.2 ± 4.8 mL vs. 26.8 ± 15.6 mL). Intraoperative hemodynamic parameters were significantly lower in group A, the number of times increases in hemodynamic parameters occurred, and fentanyl supplemental bolus was required remained significantly lower in group A than in group B. Intraoperative glycemic levels remained higher in group B, and the extubation time was significantly shorter in group A than in group B (4.40 ± 1.60 min vs. 9.2 ± 2.18 min). Group A had a lesser occurrence of postoperative delirium. Conclusion: Supplemental infraorbital block in infants undergoing cheiloplasty under general anesthesia resulted in significantly decreased anesthetic requirements and optimal hemodynamic and glycemic levels with faster extubation and lesser delirium.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권4호
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• pp.291-314
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• 2021

Squamous cell carcinoma (SCC) of the retromolar trigone (RMT) is a rare but potentially fatal disease that carries a poor prognosis due to its unique anatomic position. RMT SCCs tend to spread to vital nearby structures, including the tonsillar pillar, masticatory muscles, and underlying mandibular bone, even in their early stages, and aggressive treatment is often warranted. This systematic review appraises and qualitatively analyzes all available literature regarding the survival outcomes and prognosis of RMT SCC. Four databases were searched to identify all eligible articles published since January 1980. Of the 1,248 studies, a total of 15 studies representing 4,838 cases met the inclusion criteria. The evaluated patients had a high rate of advanced tumor stage (T3 or T4: 61.4%), lymph node metastasis (38.8%), and mandibular bone invasion (24%) at the time of diagnosis. Aggressive surgical treatments such as lip-splitting (92%), segmental mandibulectomy (61.1%), radical neck dissection (44.1%), and reconstruction using free flaps (49.5%) was undertaken for 92% of the pooled patient population. The mean rates for local, regional, and systemic recurrence were 23.40%, 8.40%, and 8.50%, respectively. The mean 5-year overall survival rate was 38.90%. Osteonecrosis was noted in 11.6% of the 328 patients who received radiotherapy. In conclusion, RMT SCC is generally associated with high recurrence, low survival, and high postoperative complication rates. Early diagnosis and aggressive treatment are thus warranted. However, significant methodological problems hamper current knowledge. Future studies of this topic that use randomized or cohort designs are thus needed.

• 대한치과교정학회지
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• 제52권1호
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• pp.42-52
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• 2022

Objective: This study compared soft tissue changes after extraction of the four premolars followed by maximum retraction of the anterior teeth according to the type of anterior teeth movement: tipping and translation. Methods: Patients who had undergone orthodontic treatment involving the extraction of four premolars were retrospectively selected and divided into either the tipping (n = 27) or translation (n = 26) groups based on the retraction of the incisor root apex and the axis changes of the incisors during the treatment period. Lateral pre- and post-treatment cephalograms were analyzed. Results: There were no significant differences between the tipping and translation groups before treatment. The retraction amounts of the root apex of the upper and lower incisors in the tipping group were 0.33 and 0.26 mm, respectively, and 5.02 and 5.31 mm, respectively, in the translation group (p < 0.001). The posterior movements of soft tissue points A and B in the tipping group were 0.61 and 1.25 mm, respectively, and 1.10 and 3.25 mm, respectively, in the translation group (p < 0.01). The mentolabial sulcus angle increased by 5.89° in the tipping group, whereas it decreased by 8.13° in the translation group (p < 0.001). Conclusions: An increased amount of retraction of the incisor root apex led to the increased posterior movement of soft tissue points A and B, and this appeared more distinct in cases involving the lower incisor and lower lip.

• 대한치과교정학회지
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• 제52권1호
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• pp.53-65
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• 2022

Objective: Planning of incisal position is crucial for optimal orthodontic treatment outcomes due to its consequences on facial esthetics and occlusion. A systematic summary of the proposed parameters is presented. Methods: Studies on Google Scholar^©, PubMed^©, and Cochrane Library, providing quantitative information on optimal central incisor position were included. Results: Upper incisors supero-inferior position (4-5 mm to upper lip, 67-73 mm to axial plane through pupils), antero-posterior position (3-4 mm to Nasion-A, 3-6 mm to A-Pogonion, 9-12 mm to true vertical line, 5 mm to A-projection, 9-10 mm to coronal plane through pupils), bucco-lingual angulation (4-7° to occlusal plane perpendicular on models, 20-22° to Nasion-A, 57-58° to upper occlusal plane, 16-20° to coronal plane through pupils, 108-110° to anterior-posterior nasal spine), mesio-distal angulation (5° to occlusal plane perpendicular on models). Lower incisors supero-inferior position (41-48 mm to soft-tissue mandibular plane), antero-posterior position (3-4 mm to Nasion-B, 1-3 mm to A-Pogonion, 12-15 mm to true vertical line, 6-8 mm to coronal plane through pupils), bucco-lingual angulation (1-4° to occlusal plane perpendicular on models, 87-94° to mandibular plane, 68° to Frankfurt plane, 22-25° to Nasion-B, 105° to occlusal plane, 64° to lower occlusal plane, 21° to A-Pogonion), mesio-distal angulation (2° to occlusal plane perpendicular on models). Conclusions: Although these findings can provide clinical guideline, they derive from heterogeneous studies in terms of subject characteristics and reference methods. Therefore, the optimal incisal position remains debatable.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제48권2호
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• pp.85-93
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• 2022

Objectives: The aim of this study was to compare morbidities and duration of surgery, as well as bone formation in alveolar defects reconstructed with symphysis bone combined with allograft and iliac crest bone graft in patients with cleft palate. Patients and Methods: This randomized clinical trial was performed with 22 patients with unilateral alveolar cleft with a follow-up period of 12 months. In 12 patients, alveolar defects were reconstructed with chin bone graft plus allograft (Group A), while for the other 10 patients, iliac bone crest was used as donor site (Group B). Duration of surgery as well as occurrence of morbidities and complications were recorded. In addition, cone-beam computed tomographic (CBCT) scans were performed before surgery and 12 months after surgical procedures in order to compare bone formation between the two groups. Results: Postoperative CBCT demonstrated a mean bone fill percentage of 76.9% of the alveolar defect in Group A, compared with 77.0% in Group B. Paresthesia in the lower lip or chin did not occur in any patients of Group A. The mean duration of the surgical process was significantly shorter for Group A (40 minutes vs 76 minutes, P<0.001). In addition, patients in Group A regained normal gait faster than patients in Group B (1 day vs 9.5 days). Conclusion: Mandibular symphysis bone graft in combination with allograft results in favorable outcomes in patients with unilateral alveolar clefts.

• 대한두경부종양학회지
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• 제38권1호
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• pp.53-57
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• 2022

Reconstruction of subtotal maxillectomy defects with columella deficit is challenging. We report a unique case of facial reconstruction using a free radial forearm flap and a free preauricular flap for the maxillectomy and columella deficit. A 73-year-old woman was diagnosed with recurrent sebaceous carcinoma of the nose. We performed wide excision, including areas of the right cheek, nose, upper lip, maxilla, and columella. The resultant subtotal maxillectomy defect was reconstructed using a three-dimensional flap. First, a free radial forearm flap was transfered to resurface the nasal, oral, and external facial side. Second, a preauricular flap was positioned into the columella defect and anastomosed with the distal portion of the radial forearm flap pedicle. The two flaps survived, and the patient recovered uneventfully. We believe the radial forearm and preauricular double free flaps with the pedicle connection method were effective in reconstructing the present case of subtotal maxillectomy defect.

• 대한치과보철학회지
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• 제60권4호
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• pp.330-338
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• 2022

과두 골절 및 형태 이상으로 인해 불안정한 하악 운동 및 비정상적인 안모를 갖는 무치악 환자의 경우 환자의 안정된 하악위를 찾는 것이 중요하다. 본 증례에서는 flat table 치료의치를 이용하여 환자의 안모개선, 하악 운동의 안정, 의치의 안정성이 향상시켰다. 또한 flat table 치료의치의 수직고경 및 구순 지지도를 유지하고자 CAD-CAM 기술을 이용하여 제작한 총의치 수복을 통해 환자의 불편감을 개선하는 양호한 결과를 얻었기에 이를 보고하는 바이다.

• 한방안이비인후피부과학회지
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• 제35권2호
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• pp.13-27
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• 2022

목적 : 본 연구는 인간피부각질형성세포(HaCaT keratinocytes) 모델을 TNF-α와 IFN-γ로 자극하여 내복자(萊菔子)의 피부염증 감소 및 만성 염증성 질환에 미치는 영향을 알아보고자 하였다. 방법 : 내복자(萊菔子) 에탄올 추출물(RSE)이 세포생존율에 미치는 영향을 확인하기 위하여 MTT assay를 시행하였다. 또한 RSE가 TNF-α와 IFN-γ로 자극한 HaCaT 세포에서 p-IκBα, p-ERK, p-JAK2, p-STAT1, p-STAT6의 발현과 periostin, TSLP 단백질 발현에 미치는 영향을 확인하였다. 결과 : RSE는 200㎍/㎖ 이하에서 세포 독성을 보이지 않았고, HaCaT keratinocytes에서 TNF-α와 IFN-γ자극에 의하여 증가된 IκBα, ERK의 인산화를 억제하였다. 또한 JAK2와 STAT1, STAT6의 인산화를 억제하였으며, periostin과 TSLP의 발현을 감소시켰다. 결론 : RSE는 HaCaT keratinocytes에서 pro-inflammatory cytokines 및 transcription factors의 발현을 감소시켜 피부염증 감소 효능을 보였고, 만성 염증성 질환에서 내복자(萊菔子)의 사용 가능성을 확인하였다.

• 한방안이비인후피부과학회지
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• 제35권2호
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• pp.1-12
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• 2022

Objectives : This study was conducted to verify the anti-inflammatory effects of Aster glehni water extracts in HaCaT keratinocytes. Methods : In this study, cell viability was confirmed by MTT assay. Production of TNF-α and IL-6 was determined by ELISA. mRNA expression of TARC and MDC were measusred by qRT-PCR. Also, expressions of p-JNK, JNK, p-ERK, ERK, p-p38, and p-38 were investigated by using western blot assay. Results : Aster glehni water extracts were not shown any significant cytotoxicity at 15.625-500㎍/㎖ in HaCaT keratinocytes. Aster glehni extracts inhibited the TNF-α and IL-6 production in HaCaT keratinocytes treated with TNF-α and IFN-γ. Also, expression of TARC, MDC, p-ERK, and p-STAT1 was decreased. Conclusions : These results suggest that Aster glehni water extracts have anti-inflammatory effects in HaCaT keratinocytes and can be applied to the development of anti-inflammatory treatment substances.