• The Journal of Advanced Prosthodontics
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• v.10 no.1
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• pp.58-64
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• 2018

PURPOSE. The aim of this study was to design an intraoral environment simulator and to assess the accuracy of two intraoral scanners using the simulator. MATERIALS AND METHODS. A box-shaped intraoral environment simulator was designed to simulate two specific intraoral environments. The cast was scanned 10 times by Identica Blue (MEDIT, Seoul, South Korea), TRIOS (3Shape, Copenhagen, Denmark), and CS3500 (Carestream Dental, Georgia, USA) scanners in the two simulated groups. The distances between the left and right canines (D3), first molars (D6), second molars (D7), and the left canine and left second molar (D37) were measured. The distance data were analyzed by the Kruskal-Wallis test. RESULTS. The differences in intraoral environments were not statistically significant (P>.05). Between intraoral scanners, statistically significant differences (P<.05) were revealed by the Kruskal-Wallis test with regard to D3 and D6. CONCLUSION. No difference due to the intraoral environment was revealed. The simulator will contribute to the higher accuracy of intraoral scanners in the future.

• Journal of the Korea Convergence Society
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• v.9 no.7
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• pp.135-140
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• 2018

This study aimed to determine the changes of awareness and preference of dental hygienists according to the experience of using a digital intraoral scanner through a convergence study. Data collected by an online survey for dental hygienists in Busan, Gyeongnam and Gyeongbuk were analyzed by SPSS 24.0 program. When dental hygienists had an experience of using a digital intraoral scanner, the awareness and preference of digital intraoral scanners were significantly higher. The experience of using a digital intraoral scanner showed a positive correlation with the clinical application experience of digital intraoral scanners; the clinical application experience of digital intraoral scanners, with the awareness of digital intraoral scanners; and the awareness of digital intraoral scanners, with the preference of digital intraoral scanners. In conclusion, the dental hygienist's experience in clinical application of digital intraoral scanners is expected to increase the awareness and preference, resulting in the improvement of dental hygienists' work ability. Therefore, it is believed that continuous education and learning about digital oral scanners are needed.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.4
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• pp.464-472
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• 1994

Surgical removal of the submandibular gland via intraoral approach was performed. The surgical procedure to be used for removal of submandibular gland had been performed via extraoral approach for many centuries. Disadvantages of extraoral technique are the esthetic distress due to an external scar, residual inflammation in Wharton's duct, and neurological complications. Indications of intraoral approach are unlimited in surgical cases of submandibular gland. Advantages of intraoral approach are esthetic satisfaction due to no remaining scars, preservation of adjacent anatomical structures and preservation of lower facial contour. This paper describes the surgical technique of the submandibular gland excision through an intraoral approach and variable incision lines tried. In 7 cases, excellent results were obtained after removal of the submandibular gland through an intraoral approach.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.3
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• pp.243-249
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• 1997

The purpose of this study is to describe the clinical availability of a variety of intraoral local flaps in reconstruction of oral soft tissue defects, Forty patients with oral soft tissue defects were treated by tongue, buccinator, palatal, labial, facial artery musculomucosal, buccal fat pad, and masseter muscle crossover flap. Total 43 intraoral flaps were used to reconstruct a variety of intraoral soft tissue defects, such as oronasal fistula, oroantral fistula, traumatic deformities and other. The age of patients ranged from 7 to 72 years, with mean age of 39.6 years. Follow up period ranged from 2 to 66 months, mean follow up period of 21.6 months. There were 9 complications, of which four were partial necrosis, three infections, one total necrosis, and 1 speech problem. Except for total necrosis, most of the recipient sited healed uneventually without severe morbidity. We consider that a variety of intraoral local flaps can be available for reconstruction of small of moderate large intraoral soft tissue defects.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.1
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• pp.71-78
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• 2007

The nasolabial flap has been used for reconstruction of moderate size intraoral defects. The nasolabial fold area provides an ample supply of tissue with a good color and texture match. The nasolabial flap classified advancement flap, inferiorly-based flap, superiorly-based flap. The flap is based inferiorly, so that it can easily be rotated to the intraoral defects. The nasolabial flap is chosen for the repair of various intraoral defects because of its simple elevation, proximity to the defect and its rich subcutaneous blood supply of a island flap. The subjects were 6 patients with nasolabial flap, who had reconstruction of moderate size intraoral defects. We have found the inferiorly-based nasolabial flap with a subcutaneous pedicle useful in the primary repair of surgical defects of the buccal mucosa, edentulous mandibular ridge, maxillary alveolus area and soft palate in these patients. There was no complication except one case. Intraoral hair growth was a minor problem of this patient. We thought that the inferiorly-based nasolabial flap is a useful technique for reconstruction of various intraoral defects.

• Imaging Science in Dentistry
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• v.30 no.3
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• pp.183-188
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• 2000

Purpose: This study was to evaluate the beam quality of intraoral X-ray equipments used at Yonsei University Dental Hospital (YUDH) using the half value layer (HVL) and the characteristic curve of intraoral standard X-ray film. Materials and Methods : The study was done using the intraoral X -ray equipments used at each clinical department at YUDH. Aluminum filter was used to determine the HVL. Intraoral standard film was used to get the characteristic curve of each intraoral X-ray equipment. Results: Most of the HVLs of intraoral X-ray equipments were higher than the least recommended thickness, but the REX 601 model used at the operative dentistry department and the X-707 model used at the pediatric dentistry department had HVLs lower than the recommended thickness. The slopes of the characteristic curves of films taken using the PANP AS 601 model and REX 601 model at operative dentistry department, the X-70S model of prosthodontic dentistry department, and the REX 601 model at the student clinic were relatively low. Conclusion: HVL and the characteristic curve of X-ray film can be used to evaluate the beam quality of intraoral X-ray equipment. In order to get the best X-ray films with the least radiation exposure to patients and best diagnostic information in clinical dentistry, X -ray equipment should be managed in the planned and organized fashion.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.7 no.1
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• pp.50-55
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• 1996

Acoustic analysis study was performed on 20 normal subjects by speaking nonsense syllables composed of Korean bilabial stops$(/P, P^{\star}, P^{h}/)$ and their preceding and/or following vowel /a/ (that is, $[pa, p^{\star}a, p^{h}a, apa, ap^{\star}a, ap^{h}a]$) with an ultraminiature pressure, sensor. in their mouths. Speech materials were phonated twice, once with a moderate voice, another time with a loud voice. The acoustic signal and intraoral pressure were recorded simultaneously on computer. By these procedures, we were to measure the intraoral pressure, closure duration and VOT of Korean bilabial stops, and to compare the values one another according to the intensity of phonation and the position of the target consonants. Intraoral pressure was measured by the peak intraoral pressure value of Its wave closure duration by the time interval between the onset of intraoral pressure build-up and the burst meaning the release of closure ; Voice onset time(VOT) on by the time interval between the burst and the onset or glottal vibration. Heavily aspirated bilabial stop consonant /$p^h$/ showed the highest intraoral pressure value, unaspirated /$p^{\star}$/, the second, slightly aspirated /P/, the lowest. The syllable initial bilabial stops showed higher intraoral pressure than word initial stops, and the value of loudly phonated consonants were higher than moderate consonants. The longest closure duration period was that of /$p^{\star}$/ and the shortest, /P/, and the duration was longer in word initial position and in the moderate voice. In VOT, the order of the longest to shortest was $/{p^h}/, /p/, /{p^\star}/$, and the value was shorer when the consonant was in intervocalic position and when it was phonated with a loud voice.

• The korean journal of orthodontics
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• v.51 no.2
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• pp.95-104
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• 2021

Objective: To evaluate the trueness and precision of full-arch scans acquired using five intraoral scanners and investigate the factors associated with the dimensional accuracy of the intraoral scan data. Methods: Nine adult participants (mean age, 34.3 ± 8.3 years) were recruited. Four zirconium spheres (Ø 6 mm) were bonded to the canines and the molars. Following acquisition of reference scans using an industrial-grade scanner, five intraoral scanners, namely i500, CS3600, Trios 3, iTero, and CEREC Omnicam, were used to scan the arches. Linear distances between the four reference spheres were automatically calculated, and linear mixed model analysis was performed to compare the trueness and precision of the intraoral scan data among the different scanners. Results: The absolute mean trueness and precision values for all intraoral scanners were 76.6 ± 79.3 and 56.6 ± 52.4 ㎛, respectively. The type of scanner and the measured linear distances had significant effects on the accuracy of the intraoral scan data. With regard to trueness, errors in the intermolar dimension and the distance from the canine to the contralateral molar were greater with Omnicam than with the other scanners. With regard to precision, the error in the linear distance from the canine to the molar in the same quadrant was greater with Omnicam and CS3600 than with the other scanners. Conclusions: The dimensional accuracy of intraoral scan data may differ significantly according to the type of scanner, with the amount of error in terms of trueness being clinically significant.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.4
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• pp.257-268
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• 2021

Objectives: Cleft lip and palate is a common congenital anomaly that impairs the aesthetics, speech, hearing, and psychological and social life of an individual. To achieve good aesthetic outcomes, presurgical nasoalveolar molding (NAM) has become important. Currently, the intraoral NAM technique is widely practiced. Numerous modifications have been made to intraoral NAM techniques, but the original problem of compliance leading to discontinuation of treatment remains unsolved. Therefore, the present study compared an extraoral NAM technique with the intraoral NAM technique. Materials and Methods: Twenty infants with complete unilateral cleft lip and palate were included and divided into two equal groups. Group A received the intraoral NAM technique, and Group B received the extraoral NAM technique. Pre- and postoperative extraoral and intraoral measurements were recorded. Results: Groups A and B did not differ significantly in any extraoral or intraoral parameter. Conclusion: The extraoral NAM technique is as effective as the intraoral NAM technique in achieving significant nasal and alveolar changes in complete unilateral cleft lip and palate patients. Additionally, it reduces the need for frequent hospital visits for activation and the stress associated with the insertion and removal of the intraoral NAM plate, thereby improving compliance.

• Imaging Science in Dentistry
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• v.53 no.1
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• pp.21-26
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• 2023

Purpose: A fully digital approach to oral prosthodontic rehabilitation requires the possibility of combining (i.e., registering) digital documentation from different sources. This becomes more complex in an edentulous jaw, as fixed dental markers to perform reliable registration are lacking. This validation study aimed to evaluate the reproducibility of 1) intraoral scanning and 2) soft tissue-based registration of an intraoral scan with a cone-beam computed tomography (CBCT) scan for a fully edentulous upper jaw. Materials and Methods: Two observers independently performed intraoral scans of the upper jaw in 14 fully edentulous patients. The palatal vault of both surface models was aligned, and the inter-observer variability was assessed by calculating the mean inter-surface distance at the level of the alveolar crest. Additionally, a CBCT scan of all patients was obtained and a soft tissue surface model was generated using patient-specific gray values. This CBCT soft tissue model was registered with the intraoral scans of both observers, and the intraclass correlation coefficient(ICC) was calculated to evaluate the reproducibility of the registration method. Results: The mean inter-observer deviation when performing an intraoral scan of the fully edentulous upper jaw was 0.10±0.09 mm. The inter-observer agreement for the soft tissue-based registration method was excellent(ICC=0.94; 95% confidence interval, 0.81-0.98). Conclusion: Even when teeth are lacking, intraoral scanning of the jaw and soft tissue-based registration of an intraoral scan with a CBCT scan can be performed with a high degree of precision.