SYNOPSIS

DR. WANKHADE BHUSHAN GANESHRAO

POST GRADUATE STUDENT

DEPARTMENT OF PROSTHODONTICS

INCLUDING

CROWN & BRIDGE AND IMPLANTOLOGY

K.V.G.DENTAL COLLEGE & HOSPITAL,

KURUNJIBHAG, SULLIA (DK) KARNATAKA, 574327

Rajiv Gandhi University of Health Sciences, Karnataka,Bangalore.

ANNEXURE-II: PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

1. / Name of the Candidate and Address / DR. WANKHADE BHUSHAN GANESHRAO
POST GRADUATE STUDENT,
DEPARTMENT OF PROSTHODONTICS INCLUDING CROWN & BRIDGE AND IMPLANTOLOGY.
K.V.G.DENTAL COLLEGE & HOSPITAL,
KURUNJIBHAG, SULLIA(DK)
KARNATAKA,INDIA-574 327
2. / Name of the Institution / K.V.G.DENTAL COLLEGE & HOSPITAL,
KURUNJIBHAG, SULLIA(DK)
KARNATAKA, INDIA-574 327
3. / Course of study and subject / MASTER OF DENTAL SURGERY
PROSTHODONTICS
INCLUDING CROWN & BRIDGE AND IMPLANTOLOGY
4.

5. / Date of admission to course
Title of the thesis:- / 31st May 2011.
A study to correlate the condylar guidance inclinations of dry human skull with two different radiographic images.
6. / Brief resume of the intended work :
6.1 Need for the study :
Analogue of condylarguidance on an articulator is considered as a necessary requisite in prosthodontics.1 The guidance inclination in semi-adjustable articulator is set either by individualprotrusive or lateral inter occlusalregistrations.2-5 Variations have been reported in recording condylar guidance and with its cosequative registrations, between operators, between recording materials, and between articulators.6,7
As analternative,average value settingsare used with the mean inclinationof normal adult eminence morphology.3,4Reported average interocclusal registrationvalues of condylar guidance inclination vary from 21-64 degrees.8-12 Some authors have advocated setting of condylar inclination on articulators at a flatter than average value to ensure disocclusion of posterior teeth during excursion.13-14 However, if individual inclination of eminence is very steep or flat, guidance obtained from average value setting may differ significantly to cause the problems in achieving particular clinical objectivessuch as balanced occlusion or posterior disocclusion.1
Use of radiographic images, along with interocclusalrecords and/or extra oral tracing may resolvethis potential problem.However inaccuracies of the interocclusal records had inherent errors of upto 30 degrees.9 The direct correlation of radiographic condylar guidance tracing with its anatomical counterpart has some interesting clinical implications. A significant correlation between the articular eminence inclination in dry skull and its panoramic image was found with the mean difference of 7degrees.1
This finding indicate that panoramic radiographic image of eminence can aid in setting the condylar guidance inclination.1 However, lateral cephalometric radiographs have not been used for setting the condylar guidance till date.
Hence,there is a need for further investigations to compare different radiographic imagestoevaluate their correlation with one another andto have most accurate condylarinclination that can be set onto articulator.
The purpose of the study is to correlate the condylar guidance inclination of dry human skulls with two different radiographicimages to have most accurate value that can be set on articulator.
6.2 Review of literature
A study was done to compare the sagittal condylar inclination as obtained by graphic record and intraoral wax record method,on 10 young subjects. Five records were made for each subjectand were analyzed statistically.15The error of graphic method was found to be twice that of intraoral wax method. It was concluded that the error was mainly caused by the difficulty in drawing the tangent to the curved condylar path rather than to recording itself.15
In another study, the effect of threedifferent recording materials was evaluated on the reproducibility of condylar guidance inclinations in three semiadjustable articulators. Sagittal condylar guide setting of 3 semi adjustablearticulator: Whip Mix. Hanau 158 , & Denar Mark II were compared using registration of base plate wax , copper wax , & self-cure acrylic resin in two subjects . Results showed that, Significant difference in condylar guidance setting were foundbetween pink base plate wax, acrylic & copper wax protrusive laterotrusive occlusal registrations. Of the three recording material no material gave more consistentresults.7
Another study was done to compare condylar guidance inclination angles found by the use of wax protrusive records in Hanau articulator with those found by the use of Whip Mix pantographic tracing quick set recorder.14It was concluded that, lower condylar angles were recorded from wax records when compared to the extraoral tracing device. The Wax method although practical, may result in restoration with decreased cusp height.16
A study was done to determine correlation between the anatomic shape of articular eminence and the corresponding panoramic radiographic images in dry humanskull, the result showed the significant correlation between the sagittal inclination of the anatomic articular eminence outline and the corresponding panoramic radiographic image1.
6.3 Objectives of the study:
  1. To determine the correlation between anatomic condylar guidance inclinationson dry human skulls and its corresponding lateralcephalometric images.
  2. To determine the correlation between anatomiccondylar guidance inclinations on dry human skulls and its correspondingpanoramic images.
  3. To compare the accuracy ofcondylar guidance inclinations obtained fromlateral cephalmetric and panoramic images
Materials and methods :
7.1 Source of the data
For the purpose of study, 20 dry human skulls will beselected randomly, from Department of Human Anatomy, K.V.G. Medical College and Hospital,Sullia (D.K.).
Inclusion criteria
  1. Dry skull withgood retained morphologyof articular eminence and glenoid fossa.
  2. Skull having at least one posterior maxillary tooth on each side.
Exclusion criteria
  1. Skull with edentulous maxilla.
7.2.Methods of collecting data
  1. Instruments and materials that will be used during course of study
Instruments
  1. Facebow withcustomized transfer plate.
  2. Tracing view box.
  3. Protractor.
Materials
1.Addition silicone elastomeric impression material.
2.Four metal balls of 4 mm diameter.
3.Metal solder wire.
4.X ray films.
5.Acetate tracingsheet (0.003”).
Equipment
1. Digital radiographic machine.(Planmeca Proline XC with Dimax 3.)
  1. Methodology :
Twenty dry skulls will be selected. Metal wire will be fixed to inner surface to the middle of the most concave aspect of the articular eminence in anteroposterior direction,four reference metal balls of 4 mm diameter were fixed with cyanoacrylate glue to superior border of auditory meatus& inferior anterior mostborder of orbital rims on both side as reference points, representing Frankfurt Horizontal Plane (FHP). Panoramic and lateral cephalogram will be recorded by the same operator with same panoramic radiographic unit for each skull with the wire in situ, keeping FHP parallel to upper border of filmand floor.Images will be acquired at 74 kv and 10 mA.
All radiographs will be taken in the department of Oral Medicine and Radiology, K.V.G. Dental
College and Hospital, Sullia(D.K).
The tracingof the image of wire marker of each radiograph will be made on acetate tracing paper. Two points will be marked on most superiorand most inferior part of eachcurve.These twopoints will be joined and a line will be drawn. Horizontal reference line will bedrawn joining the images of two reference balls on radiograph. Angle madeby these two lines will be compared with control group. Control group will be made by sagittaly sectioning the impressions of articular eminence and glenoid fossa along withwire in situ on right & left side for each skull using addition silicon putty. Horizontal reference plane willbe incorporated in impression, with the help of face bow and transfer plate, which will be parallel to FHplane. The outline of each curvature and the flat reference line will be traced. On tracing, a line will be drawn connecting the most superior and inferior ponts of curvature representing mean curvature line. The angle will be measured between the mean curvature line and the reference line.
  1. Collection of data:
Condylar guidance values will be obtained from human skulls, lateral cephalogram and panoramic images. These values will be tabulated and analyzed statistically.
  1. Statistical analysis
The study results will be analyzed using,
  1. Karl Pearson’s coefficient of correlation coefficient
  2. Student unpaired ‘t’ test
7.3Does the study require any investigations or interventions to be conducted on patients or other humans or animals?
No
7.4Has the ethical clearance been obtained from your institution in case of 7.3?
Yes
References
  1. Giloboa I, Cardash HS.Condylar Guidance: Correlation between articular morphology and panoramic radiographic images in dry human skull.J Prosthet Dent 2008;99;477-482.
  2. Posselt. Physiology of occlusion and rehabilitation. Blackwell Science.2nd ed.Oxford;1968.p 121–32.
  3. Mohl N,Zarb G,Carlsson G, Rugh J. A textbook of occlusion.Quintessence. Chicago 1988. p 139–40.
  4. Zarb G, Bolender C. Prosthodontic treatment for edentulous patients: complete dentures and implant-supported prostheses.12th ed. St Louis:Mosby; 2004, p. 294.
  5. Rosensteil S, Land M, Fujimoto J. Contemporary fixed prosthodontics. 4th ed. St Louis:Mosby;2006. p. 71.
  6. Gross M, Nemcovsky C, Friedlander LD. Comparative study of condylar settings of three semiadjustable articulators. Int J Prosthodont.1990;1:135–141.
  7. Gross D, Tabibian Y, Gazit E. The effect of three different recording materials on the reproducibility of condylar guidance registrations in three semi-adjustable articulators. J Oral Rehabil.1998;89:204–208.
  8. Gysi A, Practical application of research results in denture construction.J Am Dent Assoc .1929;16:199–23.
  9. Isaacson D, A clinical study of the condylar path. J Prosthet Dent.1959;9:927–35.
  10. Lundeen H, Shyrock H and Gibbs C, An evaluation of mandibular border movements: their character and significance. J Prosthet Dent,1978;40:442–52.
  11. Lundeen,Wirth G, Condylar movement patterns engraved in plastic blocks.J Prosthet Dent.1973;30:866–75.
  12. Preti G, Scotti R, Bruscagin C Carossa, A clinical study of graphic registration of the condylar path inclination. J Prosthet Dent.1982;48: 461–466.
  1. Gracis S, Clinical considerations and rationale for the use of simplified instrumentation in occlusal rehabilitation. Part 2: setting of the articulator and occlusal optimization. Int J Periodontics Restorative Dent, 2003;23:139–45.
  2. Dawson P. Evaluation, diagnosis and treatment of occlusal problems. 2nd ed.St Louis: Elsevier;206–237.
  3. Posselt U, Odont, Skytting B. Registration of the Condyle Path Inclination: Variations Using Gysi Technique. J Prosthet Dent.1960;3:243-24.
  4. Jose dos Santos, Nelson S, Nowlin T.Comparison of condylar guidance setting obtained from a wax record versus an extraoral tracing: A pilot study. J Prosthet Dent 2003; 89:54-9.

9. / Signature of the candidate
10 / Remarks of the guide
11 / Name and designation( in block letters) of
11.1 Guide / DR. DEVIPRASAD NOOJI
READER
11.2 Signature
11.3 Co-Guide
11.4 Signature
11.5 Head of the department / PROF. DR. PRANAV MODY
PROFESSOR AND HEAD OF THE DEPARTMENT
11.6 Signature
12.1 Remarks of the chairman and principal
12.2 Name And Signature of Principal / PROF. DR. MOKSHA NAYAK