PROFORMA FOR REGISTRATION OF SUBJECT FOR DISSERTATION
Name of the candidate and address
Dr. AGNELO MICHAEL REVEREDO
House No. 907/D
P.O Raia, Santemol ,
PIN : 403720
VS Dental College and Hospital,
KR Road , VV Puram,
Name of the institution
Vokkaligara Sangha Dental College & Hospital,
Bangalore – 560004
Course of the study and subject
Master of Dental Surgery (M.D.S.)
Department of Prosthodontics
Date of admission to course
Title of the topic:
COMPARATIVE ANALYSIS OF THE ELEMENTS OF OCCLUSION IN CANINE GUIDED OCCLUSION AND GROUP FUNCTION OCCLUSION USING T-SCAN - A CLINICAL STUDY
6. BRIEF RESUME OF THE INTENDED WORK
6.1 NEED FOR THE STUDY
Computerized occlusal analysis is becoming the principal tool available to clinicians with which to understand functional and parafunctional forces of occlusal contact, contact timing sequences and occlusal surface interface pressures, which arise as teeth mill against each other during mandibular movements.
Because recent literature on articulating paper has revealed that articulating paper mark size does not measure occlusal forces predictably, the modern clinician needs to employ an occlusal contact measuring device to reliably determine aberrant occlusal force concentrations and time prematurities.1
In canine guided occlusion maximum intercuspation coincides with the optimal condylar position of the mandible (centric relation). During lateral or protrusive excursions the canines contact and guide the mandible so that no posterior occlusal contacts occur. Therefore protecting the remaining dentition from adverse occlusal tortional forces on contacts to and from centric occlusion (and/or centric relation) .In group function occlusion the contacts are shared between several teeth on the working side during a lateral excursion.2
The purpose of the study is to compare the relation between the Center of force, Occlusal load distribution, disocclusion time and the intensity of bite among the population with canine protected occlusion and group function occlusion using the T-scan apparatus.
Components of T-Scan System
1. Processing Unit
2. Occlusal sensor
3. Color monitor
The T-scan III Computerized Occlusal Analysis System for Windows® (Tekscan) accurately records dynamic occlusal force movies in real time 0.003sec increments and then plays them forwards and backwards incrementally , in a dynamic Force Movie to clearly illustrate the locations and timing order of occlusal contact force and time abnormalities5.
The T-scan system can help detect
Occlusal force distribution :
Measurement of the percentage of force distribution within the arch and on individual tooth
Occlusion time :
The time from first point of contact to Maximum Intercuspation
Disocclusion time :
The elapsed time in seconds measured from the beginning of a jaw movement made in one direction, when all teeth are in complete contact, through until only canines or incisors are in contact
Center Of Force :
Pinpoints the location of the sum of the total force of the occlusal contacts. The center of force trajectory displays the path of the Center of Force from the beginning of the recording to the point of closure selected.
Current research on articulating paper mark size has revealed that the size of an articulating paper mark does not describe occlusal forces. A given mark of virtually any size or color intensity (large, small, scratch-like; light, dark) could hold a range of loads (from 0 N to 500N) despite its “size” appearance. The study also showed that similar, equally sized marks on neighboring teeth did not represent equal loads.8
T-Scan Sensor is 67 micrometer thick, made of mylar film.
Resistant to perforation, strength and tear
Contains approximately 1100 sensels in small and 1300 sensels in large sensor.
Each sensor can record an estimated 15-20 Bites or Closures per patient
As the patient bites on the sensor that contains sensels, a change in the applied force at various tooth contacts results in a voltage drop in each loaded sensel, which translate the electronic measure of relative forces to display them as images on the screen.
6.2 REVIEW OF LITERATURE:
Several studies have been performed to compare the effects of canine guidance and group function on elevator electromyographic (EMG) activity. Some authors have found significantly lower EMG activity with canine guidance than with group function, whereas other authors found no significant differences3.
Recent literature on articulating paper has revealed that articulating paper mark size does not measure occlusal forces predictably, therefore the modern clinician needs to employ an occlusal contact measuring device to reliably determine aberrant occlusal force concentrations and time prematurities1.
Studies have shown that the T-scan apparatus is effective in providing diagnostic information such as the distribution of forces by percentage around the arch,the timing of the forces as to which forces are early or late, the presence of interferences to closure, the balance of forces left to right and/or front to back at any point in closure, the effectiveness of guidance patterns that provide somatosensory muscle control, evidence of muscle balance or imbalance during function, evidence of abnormal dental forces secondary to injury, pain, or inflammation and presence and timing of forces that are above or below average for this patient.4
6.3 OBJECTIVES OF THE STUDY:
1) To compare the disocclusion time in anterior guidance and lateral excursion
2) To compare the trajectory of center of occlusal force in canine guided and group function
3) To compare the percentage of occlusal load distribution in canine guided and group
4) To compare the occlusal contacts in maximum intercuspation using T-scan apparatus in
patients with canine guided and group function occlusion
Before screening the subject is made to understand the procedure and consent is obtained from the subject for the study. 80 subjects will be selected according to the inclusion and exclusion criteria stated above. They will be divided into two groups based on sex. Each group will be further divided into two subgroups based on type of occlusion, ie canine guided or group function occlusion. The intra oral occlusal sensor will be covered with a mylar cover sleeve and the subject will be asked to bite on the sensor. After the occlusal data is recorded, the same patient will then be asked to bite on the sensor again followed by protruding the mandible inorder to record the disocclusion time due to anterior guidance. Once this is recorded the patient will be instructed to bite and make excursive movements to the left and right, and again disocclusion time is recorded. The data will give the trajectory of center of force, occlusal load distribution, disocclusion time and the occlusal contacts in maximum intercuspation. The recorded data will be subjected to statistical analysis using the ANOVA / Kruskal-Wallis test.
Does the study require any investigation or intervention to be conducted on patients or other humans or animals? If so, please describe briefly.
Has ethical clearance been obtained from your institution in case of above?
I ________________ son / daughter of _____________________ aged ________, declare that Dr Agnelo Michael Reveredo has explained to me about the T-scan system and its advantages and disadvantages and the risk involved for this study. I hereby give my voluntary consent to be a part of the study inspite of the risks involved.