The Occlusal Plane Orientation in Complete Denture Success: Principles and Practices

Purpose: Evaluation of relationship between various anatomical landmarks and the occlusal plane in the natural dentition that could be used for establishing the occlusal plane in complete dentures. Methods: The study comprised of 100 dentulous subjects with all healthy permanent teeth in normal arch form and alignment. Three instruments were custom-made for the purpose: the occlusal plane analyzer to check the parallelism of the ala-tragus lines, and the interpupillary line, the buccinator groove relator and the level analyzer for the level of the linea alba buccalis with the occlusal plane. For the retromolar pad area a metallic scale was used. Results: Within limitations of this study, it was observed that, only 13% subjects showed occlusal plane parallel to the interpupillary line. The posterior reference point of Camper′s line was middle point for 72% of males and superior point for 80% of females. Intraorally, 68% of subjects have the occlusal plane at the same level as that of buccinator groove and 77% of the subjects had the occlusal plane at the middle one-third of retromolar pad area. Interpretation and Conclusions: It was concluded that: the occlusal plane is parallel to Camper′s plane posterior reference point as the superior point of tragus in females and middle point in males. The occlusal plane is not generally parallel to the interpupillary line. Intra-orally, the level of buccinator groove is reliable, while variations in retromolar pad area make it an unreliable landmark for orienting the occlusal plane.

Introduction: Occlusal plane is the average plane established by incisal and occlusal surfaces of teeth. Various anatomic landmarks are used to determine this missing component of occlusion which is lost with the loss of teeth. However, variation has been observed in the orientation of occlusal plane determined clinically with different anatomical landmarks as references. Objective: This study was undertaken to determine the relation of intraoral anatomic soft tissue landmarks, namely, retromolar pad and parotid papilla with occlusal plane in natural dentition. Materials and Methods: Irreversible hydrocolloid impressions of 100 edentulous individuals (50 males and 50 females) were made to get the models. A 16 gauge wire was extended from mandibular occlusion plane posteriorly up to retromolar pad to establish their relationship. Furthermore, vertical distance of apex of parotid papilla to maxillary molar cusp tip it opposed (distobuccal cusp of maxillary first molar or mesiobuccal cusp of maxillary second molar), and mandibular molar cusp tip (to which parotid papilla apposed) was measured when the teeth were in maximal intercuspal position. Results: This study determined that the natural occlusal plane is oriented posteriorly at the level corresponding with the lower third of retromolar pad. Mean distance of parotid papilla above the corresponding maxillary cusp tip (while in occlusion) was 5.048 mm, and mean distance of Parotid papilla above the corresponding mandibular molar cusp tip (while in occlusion) was determined to be 3.602 mm. The difference in observed means between males and females or between right and left side was not statistically significant.

Understanding the relationship between condylar guidance (CG), occlusal plane orientation, cuspal inclination, and compensatory curves in natural dentition is important in orthodontics for ensuring post-treatment stability and managing temporomandibular joint disorders. Therefore, the study's objective is to assess the relationship between the compensatory curve in natural dentition, the inclination of functional cusps and occlusal plane, and CG. Condylar guidance, occlusal plane and cuspal inclination, and the compensating curve were measured in 56 pretreatment samples (lateral cephalograms and study models). The study models' STL images, digital cephalometric tracing with FACAD software, and 3D scanning technology (Shining 3D Auto Scanner) were used to evaluate the parameters. The associations between cuspal inclination, occlusal plane orientation, CG, and the compensating curve were evaluated using multivariate correlation analysis. The analysis revealed an insignificant correlation between CG, occlusal plane and cuspal inclination, and the curve of spee. Furthermore, it shows statistically insignificant relationship, indicating that variations in these factors do not significantly influence each other. There is no substantial evidence to suggest a direct correlation between the factors of CG, occlusal plane and cuspal inclination, and the compensatory curve in natural dentition. These findings imply that changes in occlusal morphology and plane inclination during orthodontic treatment do not have a significant impact on CG or post-treatment stability. How to cite this article: Raja VK, Anbarasu P, Dinesh SPS, et al. An Evaluation of the Relationship between Condylar Guidance, Occlusal Plane Orientation, Cuspal Inclination, and Compensatory Curves in Permanent Dentition. J Contemp Dent Pract 2025;26(4):377-382.

In vitro comparison of the maxillary occlusal plane orientation obtained with five facebow systems

To evaluate the parallelism of natural maxillary occlusal plane with inter-pupillary line and ala-tragus line, and to evaluate the anatomic relationship of natural mandibular occlusal plane with retromolar pad among dentate subjects. The cross-sectional study was conducted from September 2017 to February 2018 at Fatima Jinnah Dental College, Karachi, and comprised front and profile photographs of subjects aged 20-28 years while holding the camper's plane against the maxillary occlusal plane. The photographs were imported in a software and an interpupillary line was drawn and the angle with Camper's plane was measured. On both profile pictures, lines were drawn from base of the ala to the superior, middle and inferior points on the tragus. The angle between ala-tragus line and Camper's plane were measured. Intra-orally, height of the mandibular occlusal plane in relation to the retromolar pad was evaluated using a stainless steel scale. Data was analysed using SPSS 23. Of the 109 subjects with a mean age of 23.03±1.36 years, 76(69.72%) were females. Horizontal parallelism of occlusal plane with inter-pupillary line was observed with a mean angle of 1.17±1.27 degrees. The angle between the occlusal plane and the inferior ala-tragus line was 4.25 degrees on the right side, and 4.50 degrees on the left. Intraorally, mandibular occlusal plane coincided with the inferior 48(44%) and the middle third 48(44%) of the retromolar pad. Inter-pupillary line and retromolar pad area should be used as a guide in the determination of plane of occlusion. The ala-tragus line was not found to be a reliable guide.

Background and aim: Assessment of dentofacial asymmetries and other discrepancies that can affect the horizontal reference lines should be considered initially as a part of the esthetic diagnosis. Some variations of facial asymmetry are not considered an esthetic liability. So the aim of the present study is to determine a layperson’s preference regarding transverse occlusal plane (TOP) orientation in fabrication of a complete denture.Materials and methods: A total of 100 subjects who are edentulous and have enrolled for complete denture fabrication were selected. Photograph of the patient’s face was obtained from the frontal perspective on the day of try-in. The image obtained was edited to orient the occlusal plane in three different cants, zero degree, two degrees, and four degrees to the inter-pupillary line (IL) and presented to the patient. The obtained results were statistically analyzed.Results: The observed data was analyzed using Friedman’s test and Wilcoxon test was used for comparing ordinal data between groups. There was a statistically significant difference in acceptance depending on angulation, χ2(2) = 183.2, p = 0.0001.Conclusion: A cant of two degrees is not perceived by the subject but some subjects’ preference of occlusal plane may be altered according to the commissural canting which cannot be incorporated in complete denture fabrication.

Accurate occlusal plane orientation is an essential factor in the fabrication of complete denture prosthesis. Over the years, it has received a number of methodologies by several researchers utilizing various anatomical landmarks however none of them is considered as perfect that could orient ideal occlusal plane. The presented literature review is an attempt to enlighten historical perspectives, pioneer researches, different controversies, difficulties and current trends for re-establishment of lost occlusal plane in edentulous patients. An extensive literature search was performed using Medline/PubMed interface and other scholarly research bibliographic databases using Medical Subject Headings. Studies describing research studies, case series and assorted clinical reports were retrieved and evaluated from 1963 to 2013. Most of the studies have suggest and evidence to consider Camper's plane for artificial orientation of occlusal plane however there is a substantial lack of genuine long term studies and authentic data that could recommend a single reliable landmark for perfect occlusal plane reorientation in a variety of cases.

Background/Objectives: Pathological tooth loss resulting from poor oral hygiene or systemic diseases can lead to partial edentulism, affecting patients both psychologically and physically. These consequences include facial height reduction, temporomandibular dysfunction, and impaired phonetics and mastication. Immediate complete dentures are often an effective provisional solution during the transition to full edentulism; however, establishing the occlusal plane can be challenging when remaining teeth prevent a conventional wax try-in. This clinical case aims to present a qualitative clinical case study of a single patient, illustrating the use of the Broadrick Occlusal Plane Analyzer (BOPA) for the establishment of an occlusal plane in harmony with the anterior and condylar guidance. Methods: A 51-year-old male patient presented to the Department of Prosthodontics at the School of Dentistry, Autonomous University of Guadalajara, with partial edentulism, periodontal disease, and generalized Grade III tooth mobility. Immediate maxillary and mandibular complete dentures were selected as the treatment of choice. Due to the presence of remaining teeth that hindered clinical determination of the occlusal plane, the BOPA was used during the denture design process. Results: Anatomical landmarks were combined with BOPA tracing to establish an occlusal plane harmonious with anterior and condylar guidance. The center of the curve was modified to accommodate anatomic variability in anteroposterior reference points. Conclusions: The use of the Broadrick Occlusal Plane Analyzer facilitated the accurate determination of the occlusal plane for the fabrication of immediate complete dentures in a patient where clinical assessment was limited. This modification allowed the establishment of a bilateral balanced occlusal scheme, contributing to functional and acceptable provisional oral rehabilitation during postoperative alveolar healing.

Aim: The Purpose of the present review was to determine the occlusal plane in edentulous patients.Objective : Occlusal plane orientation is an important factor in the construction of a complete denture.Occlusal plane could be oriented using landmarks in the maxillary arch as well as the mandibular arch .Many methods have been used to establish the occlusal plane in complete dentures , but no method seemsto be fully acceptable. So it is always challenging for the prosthodontist to restore the existing occlusalcondition with a suitable prosthesis.Materials and Methods : : An electronic search engine without time/ language restrictions was taken fromGoogle Scholar .Conclusion: This article reviews different techniques to determine and correct occlusal plane. HIP wasparallel to the occlusal plane , Ala-tragal line passing through lower part of the ala of the nose to inferiorposition of the tragus was relatively parallel to maxillary residual ridge. Therefore, this may be a viablereference in complete denture prosthodontics.

Peter Camper described ala-tragus line for orientation of antro-posterior occlusal plane and defined it as a line running from the lower border of the ala of the nose to the tragus of the ear. Camper never mentioned exact point of reference for this line of the tragus of the ear; superior, inferior or middle. The aim of this study was to evaluate the effect of changing the posterior reference point of ala-tragus line on masticatory efficiency of complete denture wearers.Subjects and method : Ten completely edentulous patients were selected. For each patient new complete denture was constructed. The denture anterior teeth were set to meet the esthetic needs with minimal incisal guidance as much as possible. Posterior anatomic form teeth were arranged in balanced articulation with the posterior occlusal plane follow the ala tragus line at the middle point of tragus. Then, the denture posterior segments were exchanged twice to orient occlusal plane parallel to the ala tragus line at the superior and the inferior points of tragus, respectively. After three months of each new and modified denture use, masticatory efficiency test was carried out.Results: There were no significant differences of all masticatory efficiency parameters (when patients were chewing apple, peanut and carrot) with the occlusal plane oriented parallel to the Camper’s line using the three levels of the tragus.Conclusion: According to the results of the present study, the use of any posterior point of tragus for occlusal plane orientation is acceptable at the point of masticatory efficiency.

Background: For the complete dentures to look, sound, fit, and feel their best, it is crucial that the occlusal plane be positioned correctly. There are a number of different anatomical landmarks that have been proposed to arbitrate the position of the occlusal plane, with the Ala-tragus line being the most commonly adopted by the professions. Purpose: To ascertain the effect of age on location of Ala-Tragus line. Materials and methods: One hundred and seventy six patients (128 males and 48 females) having complete dentition were recruited in the study, and grouped according to their age. Patients' right lateral profiles were photographed after they had positioned the fox plane intraorally so that it was parallel to the occlusal plane. Images were taken with Canon camera model no. EOS 700 D with a resolution power of 18.0 Mega pixels, images produced were transferred to computer and traced using computer software AutoCAD 2014 and angle between Fox plane and superior, Middle and inferior borders of Ala-tragus and angle measured between three different lines. Data obtained was statistically analyzed using Pearson chi-square test. Results: There was a statistically significant relationship between age and Ala-Tragus line height. When the middle tragal border was used as the posterior reference point in the analysis, the occlusal plane was also shown to be more parallel to the Ala-tragus line age groups A, C, and D, being 42.0% (74/176). The second common location was the superior line in age groups B and D, being 36.9% (65/176), and the least common location was found to be the inferior line in almost all age groups, being 21.0% (37/176). Conclusion: Within the limitations of this study, it can be concluded that a definite relationship exists in between age and level of Ala-tragus line. Keywords: Ala-tragus line, interpupillary line, occlusal plane

Esthetic smile preferences and the orientation of the maxillary occlusal plane

Occlusal plane orientation is an important factor in the construction of a complete denture. Occlusal plane could be oriented using landmarks in the mandibular arch as well as in the maxillary arch. In the mandibular arch there are few landmarks which could be used to orient the occlusal plane like the retromolar pad, corner of the lips (lower lip length) whereas the maxillary arch has a number of landmarks, of which the ala-tragal line is the most commonly used and the same being the most controversial. In the following article different landmarks and its accuracy for orientating the occlusal plane in an edentulous subject as studied by various authors has been discussed.

Complete denture fabrication requires multiple clinical and laboratory steps. One of the most critical clinical steps is establishing an anatomical occlusal plane based on hard and soft tissue references. The aim of this study was to determine whether age or gender affects the level of the Ala-Tragus plane to establish which reference point on the Tragus should be used when fabricating the occlusal plane in edentulous patients. Clinical photographs and lateral cephalometric radiographs with complete dentitions were taken from 58 volunteers at the DMD clinic at the University of Kentucky. Each photograph was superimposed over its corresponding cephalometric image. An analysis was conducted to establish the angle of the occlusal plane relative to the Ala-Tragus landmarks; this data was then grouped according to age and gender. The analysis shows that age and gender did not significantly affect where the Camper’s plane should be approximated for complete denture treatment. However, it was found that the most parallel line to the occlusal plane was Ala’s inferior border to the ‘Tragus’s inferior border. It should be noted that the volunteers’ skeletal classification was significantly related to a Cl III malocclusion tendency. Still, with this new information, functionality and esthetics can be more adequately addressed for patients undergoing complete denture treatment. Given our results, we suggest redefining the ‘Camper’s plane with a line extending from ‘Ala’s inferior border to the ‘Tragus’s inferior border instead of the superior border. Further consideration should be taken if the patient is a skeletal CL III malocclusion.

Background: The establishment of the occlusal plane is a very important facet in conventional prosthodontic rehabilitation to restore the occlusal contact to the original condition with the ambience of a harmonious stomatognathic system. The ideal position of artificial teeth in complete denture in the same position of natural teeth will be achieved by the orientation of occlusal plane similar to the natural location of the occlusal plane. This review highlights the basic concepts and significance of the occlusal plane, it also evaluates various anatomical landmarks associated with the orientation of the occlusal plane to achieve the functional, mechanical and esthetic rehabilitation of completely edentulous patients with various treatment options like a conventional complete denture, maxillofacial prosthesis and implant-supported prosthesis. Conclusion:  This literature  review unveils the mystery of orientation of occlusal plane for completely edentulous patients by using the anatomical landmarks and reference planes. Such scientifically  established  plane of occlusion  provides biofunctional occlusion. &nbsp