الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Different types of dental restorations are being used for the treatment of patients
with unilateral distal extension edentulous areas. A unilateral partial denture is one of the
treatment modalities for the Kennedy class II partial edentulism without modification. The
absence of major connector is an advantage compared to the conventional restorations, because
of better comfort and shorter period of adaptation, still, it has not been broadly used due to their
potential problems that can result from lack of retention and stability that could therefore affect
the prognosis of the supporting structures, in addition to denture displacement during function.
The use of telescopic design partial denture provides adequate direct retention, proper stress
distribution, and indirect retention while still satisfying the esthetic requirements by eliminating
standard metal clasps. The incorporation of the attractive glass abutment in the telescopic design
partial denture may add to the design by improving the stress distribution hence decrease the
exaggerated loads transmitted to the supporting structures which is the major problem faced in
distal extension removable partial dentures.
Study objective: The aim of this in vitro study was to measure and compare the strain on the
supporting structures of class II maxillary tooth-tissue-supported telescopic partial denture with
different prosthetic designs with and without using the glass abutment using strain gauge to find
out the effect of glass abutment in stress distribution.
Materials and methods: A laboratory study was executed. Three groups of class II maxillary
telescopic partial dentures were constructed of BioHPP denture base material using CAD/CAM
technology, each group contained six specimens; group A class II maxillary telescopic partial
denture with cross arch stabilization and without using the glass abutment, group B class II
maxillary telescopic partial denture with cross arch stabilization supported distally with the glass
abutment at the site of the second molar tooth and group C class II maxillary telescopic partial
denture without cross arch stabilization supported distally with the glass abutment at the site of the
second molar tooth. By using a universal testing machine and strain gauge, the stresses around the
abutment teeth and the distal extension saddle were measured on a maxillary class II epoxy model
with missing first and second molar teeth under 200N vertical and oblique loads.
Results: A comparison of the results obtained during vertical and oblique loading showed
significant differences between mean microstrain records under vertical and oblique loads
within the same group detected in the three groups at all the examined aspects. During vertical
and oblique loading, the highest mean microstrains were recorded distal to the second premolar,
in all groups. group A showed the statistically significant highest mean microstrains record
between the three groups at the distal aspect with the worst pattern of stress distribution.
Conclusion: Reduction of stress to the abutment teeth was observed with the use of glass
abutment, it seems that the glass abutment has allowed redistribution of stresses between the
abutment teeth and the ridge.