الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 111 |  |  |
| | | from | 111 | | |
Abstract
Some implant companies have recognized the challenge of minimal bone presence and made implants of narrow diameter commercially known as Hybrid -implant 2.9mm.
A strain gauge analysis study was conducted to assess and compare the stresses induced by six Hybrid implants, ball type (2.9mm, 10mm) supported maxillary overdentures on the supporting structures in comparison to stresses induced by four Hybrid implants, ball type (2.9mm, 10mm) overdentures.
Two identical acrylic maxillary models representing maxilla were used for this study. The ridge was modified to replicate the resilient features of the mucosa overlying the residual ridge area.
Six Hybrid implants 2.9 mm in diameter and 10 mm in length with ball head design were placed in the canines, first and second premolars area of one model. While, four Hybrid implants 2.9 mm in diameter and 10 mm in length were placed in the canines and second premolars area of the other model.
Two identical maxillary overdentures supported by implants were constructed.
A loading device, Universal Testing Machine was used to produce a standardized static load of 70 N between the second premolar and first molar teeth both unilaterally and bilaterally.
Four channel strain meter was used to assess and record the strains induced, mesial to the anterior implants at canine area and distal to the posterior implants at second premolars area.
Micro-strains were recorded at each site of the strain gauge attached to the model during unilateral and bilateral loading. The data were statistically analyzed.
The results of this in vitro study showed that, more strains were induced to the maxillary supporting structures of the four Hybrid implants supported overdenture compared to the six Hybrid implants supported overdenture during unilateral and bilateral loading.
Comparing the microstrains recorded during bilateral loading on the two models revealed statistical significant difference between them. Also, the microstrains recorded on the right side (unloaded) during unilateral loading showed statistically significant difference. Also, the microstrains recorded on the left side (loaded) during unilateral loading showed statistically significant difference.
Based on the data obtained from this study it can be concluded that:
The support provided by four Hybrid implants induce more strains to the overdenture supporting structures compared to the six Hybrid implants.