الفهرس 
Distal extension removable partial denturesOnly 14 pages are availabe for public view
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Abstract
Distal extension removable partial dentures exhibit composite type of support which leads to movement of the denture base under loading. This movement leads to transmission of high amount of stresses to the supporting structures. Many methods were proposed to control and distribute these stresses.
This simulation study was conducted to determine and compare the effect of different telescopic crown design retainers on the stresses transmitted to the structures supporting distal extension partial dentures using strain gauge technology.
An acrylic experimental dentulous mandibular model was modified to Kennedy Class I with first premolars as the last standing abutments. This model replicates the anatomic features of the teeth, their investing structures and the mucosa covering the ridge. Abutments on the model were reduced to exhibit the same height and taper angle and primary copings were constructed and cemented on the abutments.
Three RPDs having the same design except for the telescopic crown retainers placed on the abutments which were the tested variables, were constructed using the same materials and technique. The different designs of telescopic crowns were telescopic crown with no clearance, telescopic crown with occlusal clearance and telescopic crown with cervical clearance.
Four channel strain meter was used to assess and record the strains induced to the abutments and residual ridge. Two strain gauges were installed in the distal wall of the socket of the abutment teeth. The other two strain gauges were installed on the buccal side of the residual ridge at the first molar area.
A loading device was used to produce a standardized static load of 100N on the second premolar and first molar area unilaterally and bilaterally. Microstrains were recorded at each site of the strain gauge during unilateral and bilateral loading with enough time elapsed between each loading to allow complete rebound of the resilient structures.