• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.7-24
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• 1988

The stable occlusion in function is thought as important as the esthetics in form, in order to preserve the healthy oral condition. The stable occlusion requires the harmony between the condylar guidance factors and the anterior guidance factors. The aim of this study was to evaluate the quantitative relationship between the condylar guidance factors and the anterior guidance factors, estimating statistically the measurement of the condylar paths by Pantronic and those of the anterior guidance factors, craniofacial morphology by roentgenocephalometry in 46 relatively good functional occlusion. The results of this study were as follows. 1. The measurements of the protrusive condylar path inclinations were $36.41^{\circ}$ in the right, $35.63^{\circ}$ in the left, $36.28^{\circ}$ in the mean. The measurements of Fisher's angles were $8.17^{\circ}$ in the right, $6.43^{\circ}$ in the left, $6.87^{\circ}$ in the mean. 2. The anterior facial height and the lower anterior facial height made a negative correlation with the protrusive condylar path inclination. 3. The articular eminence angle relative to the artificial articulator plane showed a positive correlation with the maximum protrusive condylar path. 4. SNA and SNB made a negative correlation with the articular eminence angle, and AAP-GoMe, AAP-DcGn, the facial height ratio had a positive correlation with the articular eminence angle. 5. The angulation of maxillary incisor lingual slope, overbite and the ratio of overbite to overiet showed a positive correlation with the articular eminence angle. 6. The angulation of maxillary incisor lingual slope , overbite, and the ratio of overbite to overjet made a positive correlation with the inclination of occlusal plane, functional occlusal plane. 7. Overbite and the ratio of overbite to overjet had a positive correlation with the angulation of maxillary incisor lingual slope. 8. The anterior guidance factors were more influenced by the mean protrusive condylar path inclination and the maximum Fisher's angle, and the regression equations of those were made.

• Phonetics and Speech Sciences
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• v.11 no.3
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• pp.31-38
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• 2019

The current electromagnetic articulography study analyzes several articulatory measures and examines whether, and if so, how they are interconnected, with a focus on cluster types and an additional consideration of speech rates and morphosyntactic contexts. Using articulatory data on non-assimilating contexts from three Seoul-Korean speakers, we examine how speaker-dependent gestural overlap between C1 and C2 in a low vowel context (/a/-to-/a/) and their resulting intergestural coordination are realized. Examining three C1C2 sequences (/k(#)t/, /k(#)p/, and /p(#)t/), we found that three normalized gestural overlap measures (movement onset lag, constriction onset lag, and constriction plateau lag) were correlated with one another for all speakers. Limiting the scope of analysis to C1 velar stop (/k(#)t/ and /k(#)p/), the results are recapitulated as follows. First, for two speakers (K1 and K3), i) longer normalized constriction plateau lags (i.e., less gestural overlap) were observed in the pre-/t/ context, compared to the pre-/p/ (/k(#)t/>/k(#)p/), ii) the tongue dorsum at the constriction offset of C1 in the pre-/t/ contexts was more anterior, and iii) these two variables are correlated. Second, the three speakers consistently showed greater horizontal distance between the vertical tongue dorsum and the vertical tongue tip position in /k(#)t/ sequences when it was measured at the time of constriction onset of C2 (/k(#)t/>/k(#)p/): the tongue tip completed its constriction onset by extending further forward in the pre-/t/ contexts than the uncontrolled tongue tip articulator in the pre-/p/ contexts (/k(#)t/>/k(#)p/). Finally, most speakers demonstrated less variability in the horizontal distance of the lingual-lingual sequences, which were taken as the active articulators (/k(#)t/=/k(#)p/ for K1; /k(#)t/

• The Journal of Advanced Prosthodontics
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• v.14 no.6
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• pp.369-378
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• 2022

PURPOSE. The purpose of this in vitro study was to assess whether scanning strategies of virtual interocclusal record (VIR) affect the accuracy of VIR during intraoral scanning. MATERIALS AND METHODS. Five pairs of reference cubes were added to the digital upper and lower dentitions of a volunteer, which were printed into resin casts. Subsequently, the resin casts were articulated in the maximal intercuspal position in a mechanical articulator and scanned with an industrial computed tomography system, of which the VIR was served as a reference VIR. The investigated VIR of the upper and lower jaws of the resin master cast were recorded with an intraoral scanner according to 9 designed scanning strategies. Then, the deviation between the investigated VIRs and reference VIR were analyzed, which were measured by the deviation of the distances of six selected reference points on the upper reference cubes in each digital cast to the XY-plane between the investigated VIRs and reference VIR. RESULTS. For the deviation in the right posterior dentitions, RP group (only scanning of right posterior dentitions) showed the smallest deviation. Besides, BP group (scanning of bilateral posterior dentitions) showed the smallest deviation in the left posterior dentitions. Moreover, LP group (scanning of left posterior dentitions) showed the smallest deviation in the anterior dentitions. For the deviation of full dental arches, BP group showed the smallest deviation. CONCLUSION. Different scanning strategies of VIR can influence the accuracy of alignment of virtual dental casts. Appropriate scanning strategies of VIR should be selected for different regions of interest and edentulous situations.

• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.675-688
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• 1995

The purposes of this study were:1) to determine the normal range of CR-CO discrepancy in normal occlusion group ; 2) to evaluate the changes of condylar position and craniofacial morphology between centric relation and centric occlusion before and after stabilization splint therapy in malocclusion group outside the normal range of CR-CO discrepancy. The normal occlusion group consisted of 80 subjects who had well-balanced faces and good occlusions with acceptable Class I molar relationship. They had not been treated orthodontically and had no signs or symptoms of temporomandibular joint dysfunction. 71 malocclusion patients enrolled for orthodontic treatment at the Department of Orthodontics, College of Dentistry, Chosun University comprised the malocclusion group, little variation of growth factor by the second molar eruption. They had CR-CO discrepancy beyond normal range and were subdivided into anterior-posteriorly -[25 Class I (0$\geq$4), and 24 Class III (ANB$\leq$0)] : vertically - [20 Normodivergentscy (30$\geq$34), and 18 Hypodivergency (SNGoMe$\leq$30)] ; and sexually - [26 Male and 45 Female]. For malocclusion group, stabilization splint with mutually protected type of occlusal scheme was applied for three months. Panadent articulators, Panadent condylar position indicator (CPI), and lateral headfilm were used to investigate the influence of stabilization splint on condylar position and craniofacial morphology. The results of this study were as follows. 1. The amounts of CR-CO discrepancy in normal occlusion were that the antero-Posterior component (${\bigtriangledown}X$) was $0.56\pm0.46mm$ (Male:$0.63\pm0.42mm$, Female:$0.49\pm0.50mm$) ; the supero-inferior component (${\bigtriangledown}Y$) was $-0.75\pm0.48mm$ (Male:$-0.76\pm0.52mm$, Female:-$0.73\pm0.43mm$) : and the transverse component (${\bigtriangledown}Z$) was $-0.33\pm0.28mm$ (Male : $-0.38\pm0.29mm$, Female:$-0.31\pm0.27mm$). 2. The condylar position was in normal range after stabilization splint therapy. 3. The mandible was always rotated infero-posteriorly after stabilization splint therapy. 4. Antero-posteriorly, Class III malocclusion responded very well to the stabilization splint therapy. 5. Vertically, Hyperdivergency responded very well to the stabilization splint therapy 6. Sexually, Male responded very well to the stabilization splint therapy.

• The korean journal of orthodontics
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• v.22 no.4 s.39
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• pp.869-880
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• 1992

The purpose of this study was to evaluate the difference and relationship between the slope of articular eminence and the inclination of upper and lower incisor teeth, which are related to the functional stability of occlusion in mandibular protrusion, according to Ricketts' facial types, by the use of lateral cephalogram and SAM2 articulator in 68-adult normal occlusion without tooth missing, orthodontic treatment and occlusal equilibration. The results of this study were as follows : 1 . The angle of articular eminence slope to occlusal plane in brachyfacial type was steeper than that in dolichofacial type, but the angle of articular eminence slope to SN plane and FH plane was not different between facial types. 2. The upper incisor axis in dolichofacial type was steeper than that in brachyfacial type, but lingual surface slope of upper incisor was not different between facial types. 3. In all samples there was a positive correlation between the angle of articular eminence slope and the lingual surface slope of upper incisor to SN plane and FH plane, and in mesofacial type there was a positive correlation between the angle of articular eminence slope and the lingual surface slope of upper incisor to SN plane, FH plane and occlusal plane, and in brachyfacial type there was a positive correlation between the angle of articular eminence slope and the lingual surface slope of upper incisor to occlusal plane. 4. In all samples there was a positive correlation between the angle of articular eminence slope and the angle of Dc-Gn to SN plane, and in mesofacial type there was a positive correlation between the angle of articular eminence slope and the angle of Dc-Gn to occlusal plane, and in brachyfacial type there was a positive correlation between the angle of articular eminence slope and the angle of Dc-Gn to SN plane and FH plane. 5. In all samples there was a positive correlation between the angle of Dc-Gn and the lingual surface slope of upper incisor to SN plane and FH plane, and in mesofacial type there was a positive correlation between the angle of Dc-Gn and the lingual surface slope of upper incisor to SN plane. 6. In all samples and facial types there was a negative correlation between MP to 1 axis and condylar incisal angle.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.791-802
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• 1998

The purpose of this study was to obtain the angulation and inclination of FACC of all teeth to FH plane. Study models of 31 persons with normal occlusion were selected and mounted on the semiadjustable articulator for this study. Using T.A.R.G. with a little modified method, the angulation and inclination of FACC of all teeth to FH plane were measured and then the measurements were analyzed statistically. The obtained results were as follows. Mean, standard deviation, maximum value, and minimum value of the angulation and inclination of FACC of upper and lower teeth were obtained. $\cdot$The FACC in both upper and lower arch was progressively lingually-inclined from anterior teeth to posterior teeth. $\cdot$In the angulations of FACC of upper teeth, central and lateral incisor showed similar value. Yet, the FACC of the rest was progressively distally-angulated from the canine to posterior teeth. The FACC in lower arch was progressively mesially-angulated from anterior teeth to posterior teeth. $\cdot$The angulation and inclination of FACC of any tooth in both upper and lower teeth correlated strongly and positively with the angulation and inclination of FACC of adjacent tooth.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.91-108
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• 1990

The purpose of this study was to compare the maganitude of the discrepancies of the mounting errors in according to the states of dentitions, and to the superoinferior, anteroposterior, and rightleft driecetions. GROUP I. : Fourteen patients 22 to 26 years of age with a full complement of teeth, were used in the study. The criteria fro patient selection were a complete dentition, sparse restorarive treatment, and adequate posterior and anterior occlusan stops. And they had no sign and sympton at TMG area. GROUPII. : Eigth patients 37 to 62 years of age with bilateral free ends. The criteria for patient selection were Kennedy classification class 1 cases, and adequate posterior and anterior stops. And the opposite dentitions were a full complement of teeth. Irreversible hydrocolloid impresiion of each arch was taken of each patient. These were immediatel poured in stone and mounted on a Denar Mark II. Articulator with the arbitrary slidematic face-bow. With hand articulation th e mandibular cast was mounted to the maxillary cast in centric occlusion. Five types of interocclusal records were taken of each patient : (1) aluwax (2) baseplate wax; (3) znic oxide-eugenol pasts; (4) polyether (Ramitec); (5) modeling compound. All measurement of the five selected recording materials were compared with those of the hand-articulated full arch models in centric occlusion or maximum interdigitation. The results were as follows; 1. There were statistical differences in amount of devitation in according to the materials and the states of dentition. The amount of deviation of compound was the largest. 2. There were statistical differences in amount of deviation in complete dentition at all directions. The amount of diviation of compound was the largest. And at the right-left direction the amount of znic oxide-eugenol paste was larger than that of baseplate wax. 3. There was a statistical difference in amount of diviations in partial edentulous dentition at the superoinferior direction. The amount of deviation of compound was larger than that of znic oxide-eugenol paste. 4. There was as statistical difference in amount of deviations in partial edentulous dentition at the right-left direction. The amount of deviation of baseplate wax was larger that tnat of polyether. 5. There was not a statistical difference in amount of diviation in partial edentulous dentition at the anteroposterior direction.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.3
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• pp.246-251
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• 2014

In case of prosthesis fabrication by CAD/CAM, location, area and contour of occlusal contacts can be adjusted so more functional occlusion can be acquired. Also, errors in a manufacturing process is reduced compared to cast metal prostheses and porcelain fused metal prostheses fabricated by conventional methods such as casting and porcelain build up. Therefore, prostheses by CAD/CAM show superior occlusion accuracy. Recently, virtual articulator function has been introduced to CAD/CAM system, which reproduces mandibular movement against maxilla. Thus, it is possible to consider occlusal interference in anterior/lateral movement as well as closing movement. There have been many studies on the marginal and internal fit of prostheses using zirconia but the occlusal fit of zirconia crown fabricated by CAD/CAM has not been researched as much. In this case report, 7 zirconia crowns were designed and fabricated by CAD/CAM for total 5 patients. The models of zirconia crowns before and after occlusal adjustment during intraoral try-in were scanned for occlusal contacts, which were compared to evaluate accuracy of prostheses and understand patterns of occlusal adjustment. Most of the occlusal adjustments were done on functional cusps and slopes of zirconia crown, and the magnitude of occlusal adjustment ranged from $15{\mu}m$ to $60{\mu}m$. In the zirconia crown fabricated with CAD/CAM systems, the occlusal adjustment is a necessary procedure, so additional procedures will be needed for compensating reduced mechanical properties.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.33-38
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• 2013

Occlusal plane is a sagittal expression of dental arch form, and it composes the shape of occlusion, which is one of the most important elements of Maxillo-oral system. In this case, vertical, horizontal coordinates of bionic-median-sagittal plane was produced in articulator, and to achieve relation of left and right position of upper, lower teeth and deficits in alveola, Shilla system was used to reconstruct occlusal plane. In this case, a 41 year-old male patient visited for fracture of 10 unit metal-ceramic fixed partial denture of upper anterior teeth and for overall treatment. Clinical, radiographical, model examination was held, full mouth rehabilitation was achieved by placing dental implant. Maxillo-oral relation was recorded using Gothic arch Tracer complex and were mounted. And for the next step, we estimated original occlusal plane using Shilla system. After analysis we produced diagnosis wax pattern. On the basis of this, radiography stent was manufactured and dental implant was placed, and temporary prosthesis was made by using diagnosis wax pattern. Cross mounting and anterior guiding table were performed in order to reproduce temporary restoration morphology and bite pattern, followed by final restoration made of all ceramic crown with zirconia coping. As stated above, appropriately esthetic and functional results can be seen in using Shilla system in diagnosis and treatment procedure of full mouth rehabilitation patient.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.2
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• pp.145-156
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• 2010

Loss of posterior support may cause overloading and excessive wear of remaining teeth. Moreover, the extrusion of antagonistic teeth leads to the destruction of the occlusal plane. The loss of vertical dimension of occlusion (VDO) also emerges clinically, which may bring the loss of esthetic appearance and function. These patients who suffer from the loss of posterior support, often require vigorous periodontal treatments (osteotomy, crown lengthening) and extensive oral rehabilitation. Sixty three years old female patient visited for the prosthetic treatment of the posterior edentulous area. She had no other systematic disease and parafuctional habits for prosthetic treatment. Intraoral and radiographic examinations were done. The evaluation of VDO and vertical dimension of rest position were evaluated for proper prosthetic procedures and diagnostic wax up was done. As a result of diagnosis, VDO was increased by 2 mm considering the loss of VDO and space for the prosthetic treatment. After the pretreatments, initial preparation of teeth and provisionalization were carried out. Six weeks later of provisionalizaion, final preparation and impression was performed. Using the duralay resin copings, jaw relation was registered. The master cast was mounted and definitive restoration was fabricated. After the evaluation of esthetic and function, pick up impression for clinical remounting was done. Lucia jig was made for new jaw relation and occlusal adjustment on the articulator. Definitive restoration was delivered and the patient was periodically recalled for additional occlusal adjustment. From this case, the satisfactory functional and esthetic results through full mouth rehabilitation with increase vertical dimension were achieved.