Download 7 - rguhs

7.
Brief resume of intended work
7.1. Need for the study
The orientation of occlusal plane is lost in patients rendered edentulous and
should be relocated if complete dentures are to be functionally satisfactory.2
The problem of accurately locating the occlusal plane in the maxillo –
mandibular space is of particular importance in prosthetic treatment of the
edentulous patients.1
The question, arises in clinical practice, is how to discover which position
‘the natural occlusal plane’ after the loss of the natural teeth occupied. More
exactly, how can the optimal position of the occlusal plane be found in every
edentulous patients.1
Anatomical landmark that have been suggested to clinically determine the
position of the occlusal plane are upper lip, corner of mouth, two-third of
retromolar pad, parallel to ala-tragus line.2 The reference point found on the
soft tissue are not stable and definite therefore the use of bone reference
points increases the accuracy of the measurements.3 Radiographic
cephalometry has been used as a diagnostic tool in prosthodontics for over
five decades.3.
Hence the aim of this study is to examine the level and inclination of the
occlusal plane in dentulous subject with anatomical Frankfort horizontal
plane, with the purpose of finding more reliable guides for location the
occlusal plane in edentulous patient, and cross verifying the results obtained,
in complete denture prosthesis wearers subjects.
7.2
Review of literature
A study was conducted to examine the level and inclination of the occlusal
plane in dentulous subjects with various skeletal jaw-relationships. The
results established that the selected mean values of the angels and linear
distances between the occlusal plane and the reference planes calculated on
the probability level of 95% could be used as cephalometric indicator.1
A cephalometric study was conducted on complete denture wearer to
investigate the relationship between anatomical structure commonly used for
to determine the occlusal plane and the facial skeletal shapes. The results
showed that a significant linear correlation was found between the facial
skeletal shapes designated SN-POG and the location of camper’s plane.2
A study was conducted to test the statistical significance of correlation of
mandibular shape versus lower facial height in occlusion, using
cephalometric measurements. Results showed a higher coefficient of
correlation than the inferior gonial angle.3
A cephalometric study was conducted on dentulous subjects and complete
denture wearers to determine the location of the natural and artificial
occlusal planes as related to Camper’s plane. The result indicated that both
the natural and artificial occlusal planes were not parallel to Camper’s
plane.4
A study investigating the geometrical analysis of occlusal plane orientation
using simulated ear-rod faces bow transfer. Analysis of the three mounting
position demonstrated no change in intercuspal position within subjects.
The cephalographs showed extreme variability tin the position of the
earpiece to bony structure of the skull.5
A study was done with aim was to three dimensionally assess craniofacial
relationship in vivo. Specifically, by means of an electromagnetic three –
dimensional computerized digitizer. The method was found to be repeatable
and fast. The measurement of anterior-posterior jaw discrepancy reveled a
wide range of sagittal relationships in the analyzed subjects.6
7.3
8.
Objective of the study
To examine the level and inclination of the occlusal plane in dentulous
subjects with anatomical Frankfort horizontal plane, with the purpose of
finding more reliable guides for location the occlusal plane in edentulous
patients, and cross verifying the results obtained, in complete denture
prosthesis wearers subjects.
Material and Methods
8.1 Materials:
1.
2.
3.
4.
5.
6.
7.
Radiographic film (8x10 inch)
Lead protective apron
Radiograph developing solutions
Acetate matte tracing paper (8x10 inch)
HB lead pencil
Metallic scale
Protector
Equipments:
1. Trophy x-ray machine
2. Radiograph view box
8.2. Method
Lateral cephalometric radiograph of male and female subjects taken with
standardized technique with the teeth in the intercuspal position having
a. 28-23 teeth present in an acceptable arch form.
b. Class 1 skeletal jaw relationship
c. No history of orthodontic treatment
Divided in to two category
1. 15 subjects with age range from 20-35 years.
2. 15 subjects with age range from 36-50 years
Lateral cephalometric radiograph, of 20 male and female complete denture
wearer subjects, taken with standardized technique with the teeth in the
intercuspal position having.
a. No history of orthodontic treatment
b. Absence of metal in the denture
A geometrical analysis was performed on tracing made from lateral
cephalogram of all the subjects.
Occlusal plane and Frankfort horizontal plane where marked in the tracing
paper (occlusal plane – line extending between the mesioincial angle of
maxillary central incisors and mesiopalatal cusp of maxillary first molar.
Frankfort horizontal plane – line extending between porion and orbitale).
Angle between these two planes is measured with help of posterior. The
values of the obtained data were subjected to the statistical analysis which is
employed the following parameter.
i.
ii.
iii.
iv.
v.
vi.
9.
The mean (x) of the examined variables.
The ranges (minimum – maximum)
The standard error or deviation (SE)
The coefficient of the variation
Confidence interval for 95% probability level (P)
Student t-test to compare the result obtained, between different
groups.
8.3 Does the study require any investigation to the carried out in any
human
Yes
8.4 Has the ethical clearance has been obtained from the collage
Yes
List of the references
1. D. Sinobad, the position of the occlusal plane in dentulous subjects with
various skeletal jaw –relation. J. Oral Rehabil 1998; 15: 489-498.
2. J.Nissan, E.Barnea, C.Zelterzer, H.S.Cardash, Relationship between
occlusal plane determinants and craniofacial structures, J. Oral Rehabil
2003; 30-:587-591.
3. J. D. Orthlieb, M. Laurent, O. Laplanche, Cephalometric estimation of
vertical dimension of the occlusion, J Oral Rehabil 2000; 27:802-807.
4. H.C. Karkazis, G.L Polyzois, A study of occlusal plane orientation in
complete denture construction. J Oral Rehabil 1987; 14:399-404.
5. Jose dos Santos, Stanley J. Nelson, Pirkka Nummikoski. Geometrical
analysis of the occlusal plane orientation using simulated ear-rod faces bow
transfer, J Prosthodont. 1996; 5:172-181.
6. V.F. Ferrario, C Sforza, G Serrao, V Ciusa. A direct in vivo measurement
of the three-dimensional orientation of the occlusal plane and of sagittal
discrepancy of the Jaws, Clin. Orthod. Res. 20003; 3:15-22.