• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.3
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• pp.197-203
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• 2007

Statement of problem: It is very important to establish the suitable position for artificial maxillary anterior teeth and the orientation of occlusal plane in fabrication of the complete dentures. Incisive papilla has been considered the most useful anatomic landmark in the arranging of a maxillary anterior artificial teeth. Purpose: To determine correct position of upper anterior artificial teeth in complete denture patients, relationship of incisive papilla, intercanine line, occlusal plane were evaluated in Korean adults. Materials and Method: Maxillary casts were made in 60 Korean dentate subjects. Each cast was mounted in Hanau modular articulator using Hanau spring bow. Then, anatomic landmarks were determined in each cast. Distance from central incisor to incisive papilla, distance from incisive papilla to intercanine line and discrepancies between frankfurt plane and occlusal plane were measured and analysed. Results: 1. The mean distance between the posterior point of incisive papilla and the incisal edge of central incisor was 11.20 mm (in male 11.77 mm, in female 10.55 mm) and there was no significant difference in measured values between male and female 2. The mean distance between the posterior point of incisive papilla and intercanine line was 2.52 mm (Male 2.57 mm, Female 2.35 mm) and there were no significant differencies in measured values between male and female 3. The mean discripancy between the Frankfurt plane and the occlusal plane were 9. 75 degree (Male 9.81 degree, Female 9.55 degree), and there was no significant difference in measured values between left and right sides.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.1
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• pp.41-51
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• 2005

Statement of problem. Anatomic landmarks have been used in the orientation of occlusal plane and the determination of vertical dimension for edentulous patients. Such as labial vestibules of anterior region and hamular notches, retromolar pads of posterior region are very useful anatomic landmarks for fabrication of occlusion rim because they are to be identified on master casts. Therefore, if average distances between landmarks of maxillae and mandible in dentate subjects are measured and applied, not only occlusal plane but also vertical dimension can be established initially. Purpose. The purpose of this study is to measure vertical distances between anatomic landmarks and to present a guide to the orientation of occlusal plane and the determination of vertical dimension of edentulous patients. Material and method. Upper and lower border-molded casts were made in 93 Korean dentulous subjects, mean age 25 years. Incisal edges of central incisors, bottoms of labial vestibules, hamular notches and the half level of retromolar pads were marked on casts. Measurements of vertical distances from incisal edge of central incisor to the bottom of labial vestibule, between upper and lower bottoms of labial vestibules, from hamular notch to retromolar pad and from hamular notch to the occlusal plane established by the incisal edge of maxillary central incisor and mesiopalatal cusps of both maxillary first molars were made on each cast. Results and conclusion. 1. The mean distance from the incisal edge of central incisor to the bottom of labial vestibule was 20.8mm(SD 1.7) on upper casts and 17.3mm(SD 1.4) on lower casts. 2. The mean distance between both bottoms of labial vestibules of upper and lower casts was 35.0mm(SD 2.7). 3 The mean distance from hamular notch to the half level of retromolar pad was 5.0mm(SD 1.3). 4. The mean distance from hamular notch to occlusal plane was 7.9mm(SD 1.5). 5. Distances from incisal edge of central incisor to labial vestibule on lower casts(P<0.01) and from hamular notch to retromolar pad(P<0.0001) were greater in male than in female.

• The Journal of Advanced Prosthodontics
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• v.5 no.1
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• pp.9-15
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• 2013

PURPOSE. The purpose of this study was to determine accurately the part of the tragus to be used to form the Ala-Tragal line or Camper's line in orthognathic profile patients. MATERIALS AND METHODS. 150 dentate subjects with age of 18-40 years with orthognathic profile were sampled. Life-size lateral digital photographs of the face with fox plane were taken in natural head position. Different angles between Eye-Ear plane and occlusal plane ($OT_1$-OP), Eye-Ear plane and ala-superior border of tragus ($OT_1-AT_1$), Eye-Ear plane and ala-middle border of tragus ($OT_1-AT_2$) and Eye-Ear plane and ala-inferior border of tragus ($OT_1-AT_3$) were calculated using computer software package, AutoCAD 2004. From the three angles formed by the Eye-ear plane ($OT_1$ or FH plane) and the ala-tragal lines, the one closest to the angle formed between Eye-Ear plane ($OT_1$) and occlusal plane (OP) was used to determine the occlusal plane of orientation. The obtained results were subjected to ANOVA F test, Tukey's Honestly significant difference test, followed by Karl Pearson coefficient of correlation test. P values of less than 0.05 were taken as statistically significant. RESULTS. The mean of base line angle i.e. $OT_1$-OP angle ($11.96{\pm}4.36$) was found to be close to $OT_1-AT_2$ angle ($13.67{\pm}1.93$) and $OT_1-AT_3$ angle ($10.31{\pm}2.03$), but $OT_1$-OP angle was found to be more closer to $OT_1-AT_3$ angle. Comparison of mean angles showed that $OT_1$-OP angle in both males (11.68) and females (12.51) is close to $OT_1-AT_3$ angle (males- 11.01, females- 11.95). CONCLUSION. The line joining from ala to the lower border of the tragus was parallel to the occlusal plane in 53.3% of the subjects. There was no influence of the sex on the level of occlusal plane.

• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.65-78
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• 1988

The development of good arch form, the orientation of the dentition with relation to the craniofacial skeleton and the establishment of correct relationship of axial inclination of upper and lower teeth are required in normal occlusion, but different teeth present different degrees of axial inclination. The purpose of this study was to investigate the axial inclination of upper and lower teeth by analyzing $45^{\circ}$ oblique and $90^{\circ}$ cephalometric roentgenograms of 35 Korean males and 34 females with normal occlusion. The obtained results were as follows: 1. Mean and standard deviation of mesiodistal axial inclination of upper and lower teeth related to palatal plane and occlusal plane were obtained. 2. Mesiodistal axial inclination of upper first premolar was nearly perpendicular to palatal plane, and the axis of lower first premolar was nearly perpendicular to occlusal plane. 3. There was no difference in the mesiodistal axial inclination of anteriorly positioned teeth between the three groups: third molar eruption into good alignment (Group 1), third molar impaction or partial eruption (Group 2), third molar agenesis (Group 3). 4. There were low correlationships only between the axial inclination of central incisor and the mesiodistal axial inclination of canine and first premolar, but no correlationships between central incisor and posterior teeth behind first premolar.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.1
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• pp.64-71
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• 2024

The most critical aspect of full-arch prosthodontic treatment is evaluating whether the patient's vertical occlusal dimension is appropriate, and if necessary, restoring it through increasing vertical dimension. If the vertical occlusal dimension is too low, it can lead to reduced chewing efficiency, as well as not only aesthetic concerns but also potential issues like hyperactivity of muscles and posterior displacement of the mandible. This report is about the patient dissatisfied with pronunciation and aesthetics due to an inappropriate vertical occlusal dimension resulting from prior prosthetic interventions, underwent full-arch prosthodontic restoration treatment. Through the utilization of digital diagnostic apparatus, a comprehensive evaluation was undertaken for patient's vertical occlusal dimension, occlusal plane orientation, and the condition of prosthetic restorations. Through 3D facial scanning, the facial landmarks were discerned, and subsequently, the new occlusal plane was established. This provided the foundation for a digitally guided diagnostic wax-up. An elevation of 5 mm from the incisor was determined. Comprehensive dental rehabilitation was then executed for all remaining teeth, excluding the maxillary four incisors. The treatment protocol followed a systematic approach by initially creating implant-supported restorations on both sides of the dental arch to establish a stable occlusal contact. Subsequently, prosthetic restorations for the natural dentition were generated. Diagnostic and treatment planning were established through the utilization of facial scanning. This subsequently led to a reduction in treatment complexity and an expedited treatment timeline.

• Imaging Science in Dentistry
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• v.44 no.4
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• pp.257-262
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• 2014

Purpose: This study was performed to evaluate the effect of changing the orientation of a reconstructed image on the accuracy of linear measurements using cone-beam computed tomography (CBCT). Materials and Methods: Forty-two titanium pins were inserted in seven dry sheep mandibles. The length of these pins was measured using a digital caliper with readability of 0.01 mm. Mandibles were radiographed using a CBCT device. When the CBCT images were reconstructed, the orientation of slices was adjusted to parallel (i.e., $0^{\circ}$), $+10^{\circ}$, $+12^{\circ}$, $-12^{\circ}$, and $-10^{\circ}$ with respect to the occlusal plane. The length of the pins was measured by three radiologists, and the accuracy of these measurements was reported using descriptive statistics and one-way analysis of variance (ANOVA); p<0.05 was considered statistically significant. Results: The differences in radiographic measurements ranged from -0.64 to +0.06 at the orientation of $-12^{\circ}$, -0.66 to -0.11 at $-10^{\circ}$, -0.51 to +0.19 at $0^{\circ}$, -0.64 to +0.08 at $+10^{\circ}$, and -0.64 to +0.1 at $+12^{\circ}$. The mean absolute values of the errors were greater at negative orientations than at the parallel position or at positive orientations. The observers underestimated most of the variables by 0.5-0.1 mm (83.6%). In the second set of observations, the reproducibility at all orientations was greater than 0.9. Conclusion: Changing the slice orientation in the range of $-12^{\circ}$ to $+12^{\circ}$ reduced the accuracy of linear measurements obtained using CBCT. However, the error value was smaller than 0.5 mm and was, therefore, clinically acceptable.