Sanath Shetty

Occlusal Plane Location in Edentulous Patients: A Review

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.

Short implants: A new dimension in rehabilitation of atrophic maxilla and mandible

Insufficient alveolar bone height is a common clinical situation encountered more in the posterior jaws. Advanced surgical procedures such as bone grafting, sinus lifting, and nerve repositioning are required to overcome this condition and make implant treatment possible for such patients. Prolonged healing period, increased morbidity, and longer duration of the implant treatment accompanies these procedures. Short implants are considered as a viable alternative in patients with reduced alveolar bone height to avoid more invasive surgical procedures. They simplify the implant treatment, reduce patient morbidity, shorten the duration of treatment, and make it less expensive. In the past, when machined implants were used, rehabilitation with short implants showed increased failure rate in comparison to longer implants. With the improvements in the surface topography of implants, which increase the bone implant contact, and use of adapted surgical protocols similar survival rates as that of regular implants have been reported even with short implants. Various methods to increase the functional surface area and decrease the stress on the prosthesis have greatly contributed to the increased success rate of short implants. Clinical Relevance to Interdisciplinary Dentistry Successful outcome of implant treatment depends on the coordinated efforts of various specialties Proper technique of implant placement by the surgeon and prior planning of the prosthesis by the prosthodontist is essential Maintenance and periodic evaluation of periodontal health are necessary.

Position of Occlusal Plane in Dentate Patients with Reference to the Ala-Tragal Line Using a Custom-Made Occlusal Plane Analyzer.

PURPOSE The purpose of this study was to determine which of the three positions on the tragus, (superior, middle, inferior) when joined with the ala of the nose for the ala-tragal line was most parallel to the natural occlusal plane in dentate patients. MATERIAL AND METHODS This study was carried out on 500 individuals, selected randomly and who agreed to participate in the study. A custom-made occlusal plane analyzer was used to check the parallelism between the ala-tragal line and the occlusal plane. The tragus was divided into three parts: superior, middle, and inferior. The instrument was placed in the participants mouth, and the posterior points on the tragus were determined. RESULTS For the 500 dentate participants in this study, the most common location of the posterior point on the tragus was the inferior part of the tragus (50.8%). The second most common location of the tragus was the middle part (24.7%), followed by the superior location (12.1%). CONCLUSION The results of this study indicated that the occlusal plane was found parallel to a line joining the ala of the nose and the inferior part of the tragus in a slight majority of the participants.

The selective pressure maxillary impression: A review of the techniques and presentation of an alternate custom tray design

An impression in complete dentures is the first step in the fabrication of the complete denture prosthesis. Various theories have been proposed by different authors as to how to achieve an optimum impression in different ways. Among them the most accepted is selective pressure theory, which was advocated by Carl O Boucher. In the last few decades many authors have interpreted Bouchers selective pressure in various ways making it more complicated and difficult to follow. But all the authors proposed their concepts based on the available information of the underlying functional and histologic anatomy during their time. This article reviews the various ways of achieving selective pressure as seen by different authors and also includes a custom tray design to achieve selective pressure, which is based on the newer concepts of the stress bearing and relieving areas in the maxillary edentulous impression procedures.

A clinico-radiographic study to compare and co-relate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in completely edentulous patients

Purpose: The purpose of this study was to compare and correlate sagittal condylar guidance determined by intraoral gothic arch tracing method and panoramic radiograph in edentulous patients. Materials and Methods: Twelve completely edentulous patients were selected by the inclusion and exclusion criteria. Conventional steps in the fabrication of complete denture till jaw relation were carried out. Intraoral gothic arch tracing and protrusive interocclusal records were obtained for each patient. Protrusive interocclusal record was used to program the Hanau Wide-Vue semi-adjustable articulator, thus obtaining the sagittal condylar guidance angle. Using RadiAnt DICOM software, on the orthopantomogram obtained for each patient in the study, two reference lines were drawn. The Frankforts horizontal plane and the mean curvature line (joining the most superior and the inferior points on the glenoid fossa curvature) were drawn. The mean curvature line was extended to intersect the Frankforts horizontal plane, thus obtaining the radiographic sagittal condylar guidance angle. The condylar guidance angles obtained by these two methods were compared and subjected to paired t-test. Results: There was no statistically significant difference between the sagittal condylar guidance angles obtained between right and left sides with intraoral gothic arch tracing and radiographic methods (P = 0.107 and 0.07, respectively). Conclusion: Within the limitations of this study, it was concluded that the protrusive condylar guidance angles obtained by panoramic radiograph may be used for programming semi-adjustable articulators.

Nasal reconstruction with silicone using customised impression technique

Facial defects can result from a variety of reasons including trauma, burns, infections, congenital disorders, and neoplasms which require surgical correction or prosthetic rehabilitation or both. Prosthetic replacement using various materials is the treatment of choice when other surgical options are not possible. This report presents a case of acquired nasal defect secondary to a surgically operated adenoid cystic carcinoma using silicone as the material of choice.

An In Vivo study to compare and evaluate the correlation of the facial measurements with the combined mesiodistal width of the maxillary anterior teeth between males and females

Aim: The aim of this study was to compare and evaluate the correlation of the facial measurements (interalar, intercommissural, intercanthal, and interpupillary distance) with the combined mesiodistal width of the maxillary anterior teeth between males and females. Objectives: The objectives of this study were: (a) To evaluate the correlation of the facial measurements (interalar, intercommissural, intercanthal, and interpupillary distance) and combined mesiodistal width of maxillary anterior teeth. (b) To compare the correlation of the facial measurements (interalar, intercommissural, intercanthal, and interpupillary distance) with the combined mesiodistal width of maxillary anterior teeth between males and females. Materials and Methods: This study was carried out on 120 dentate Subjects selected from Yenepoya Dental College, Mangalore. The vernier caliper was used to measure the interalar, intercommissural, intercanthal, and interpupillary distance. The mesiodistal width of maxillary anterior teeth was measured on the cast. For accuracy, every distance was measured three times and the mean taken. Results: Comparison of parameters between males and females was calculated using independent sample t-test. The values obtained for each variables are interalar distance: for males 38.89 ± 2.19 and for females 35.58 ± 2.33. Intercommissural distance: for males 50.96 ± 2.99 and for females 47.15 ± 2.97. Intercanthal distance: for males 31.92 ± 1.46 and for females 30.46 ± 2.07. Interpupillary distance: for males 65.15 ± 2.82 and for females 61.78 ± 3.18. Mesiodistal width of maxillary anterior teeth: for males 52.55 ± 1.82 and for females 51.33 ± 2.50. Conclusion: Within the limitations of this study, the study concluded there is a significant correlation between interalar, intercommissural, intercanthal, interpupillary distance, and mesiodistal width of maxillary anterior teeth in total subjects. In females, there is a significant correlation between interalar, intercanthal, interpupillary distance, and mesiodistal width of maxillary anterior teeth.

Prosthetic rehabilitation of an orbital defect for a patient with hemifacial atrophy

Removal of an eye may be indicated in cases of congenital abnormality, severe trauma, or disease such as an infection, tumor, or malignancy. The disfigurement associated with a loss of an eye is often accompanied with physical problems, psychological trauma, and a poor quality of life. A prosthetic replacement is the treatment of choice to return the individual to his normal vocation by producing an acceptable and life-like appearance. This article describes prosthetic rehabilitation of a 19-year-old male suffering from facial hemiatrophy with the loss of his left eye due to retinoblastoma when he was 2-year-old using medically graded silicone material. The technique used is simple, cost effective, and easy way for fabrication and rehabilitation of an orbital defect using silicone prosthesis where retention is achieved by a combination of silicone adhesives and tapes, and to a very small extent by bony and soft tissue undercut, hence providing better esthetic and psychological outcome. The acrylic part of the prosthesis was adhered to the socket with the help of a two-way silicon adhesive tape. Since the patient had lost his eye when he was 2-year-old, the development of eye and periorbital tissue on the defect side lead to hemiatrophy; in our approach, we have attempted to build the prosthesis in par with the normal side so that the fullness on the defect side was restored to that of the contralateral side. The fabricated facial prosthesis was durable, esthetic, and had good retention.

Evaluation of accuracy of transfer of the maxillary occlusal cant of two articulators using two facebow/semi-adjustable articulator systems: An in vivo study

Aim: The aim of this study was to compare the accuracy of the angle made by Frankfort horizontal plane-occlusal plane on maxillary casts, mounted using the respective facebows on Artex Amann Girrbach and Hanau Wide-vue semi-adjustable articulators with cephalometrically derived Frankfort horizontal plane-occlusal plane angle as a control. Subjects and Methods: Maxillary casts of 30 subjects were mounted on Hanau Wide-vue and Artex Amann Girrbach semi-adjustable articulators following facebow transfer using respective facebows. The Frankfort horizontal plane-occlusal plane angles of these casts were measured using Wixeys digital angle gauge. They were also subjected to a lateral cephalogram, and the occlusal cant was measured using RadiAnt DICOM software. Statistical Analysis: Using Pearson correlation, the accuracy of the angle made by upper member of the articulator and occlusal plane of mounted maxillary casts in each of the articulator was compared to the Frankfort horizontal plane-occlusal plane angle in lateral cephalogram. Results: A mean difference of 1.9° was found between Hanau Wide-vue articulator and lateral cephalogram and a mean difference of 3.6° was found between Artex Amann Girrbach articulator and lateral cephalogram. Statistically, Pearson correlation value (r) obtained between Hanau Wide-vue and lateral cephalogram was 0.46 and between Artex Amann Girrbach and lateral cephalogram was 0.25. Conclusion: From the statistical value (r) derived, it can be inferred that the Frankfort horizontal plane-occlusal plane angle of the casts articulated on Hanau Wide-vue articulator was more accurate in comparison to that on Artex Amann Girrbach articulator.

An evaluation of relation between the relative parallelism of occlusal plane to ala-tragal line and variation in the angulation of Po-Na-ANS angle in dentulous subjects: A cephalometric study

Aims: The aim was to evaluate if any correlation exists between variation in angulation of Po-Na-ANS angle and relative parallelism of the occlusal plane to the different tragal levels of the ear in dentulous subjects. Methodology: A total of 200 subjects were selected for the study. A custom made occlusal plane analyzer was used to determine the posterior point of the ala-tragal line. The lateral cephalogram was shot for each of the subjects. The points Porion, Nasion, and Anterior Nasal Spine were located and the angle formed between these points was measured. Statistical Analysis Used: Fischer′s exact test was used to find the correlation between Po-Na-ANS angle and relative parallelism of the occlusal plane to the ala-tragal line at different tragal levels. Results: Statistical analysis showed no significant correlation between Po-Na-ANS angle and relative parallelism of an occlusal plane at different tragal levels, and an inferior point on the tragus was the most common. Conclusion: Irrespective of variations in the Po-Na-ANS angle, no correlation exists between the variation in the angulations of Po-Na-ANS angle and the relative parallelism of occlusal plane to the ala-tragal line at different tragal levels. Furthermore, in a large number of subjects (54%), the occlusal plane was found parallel to a line joining the inferior border of the ala of the nose and the inferior part of the tragus.