| Summary: | 碩士 === 高雄醫學大學 === 牙醫學研究所碩士班 === 92 === According to the conventional concept, implants were installed to parallel with each other and perpendicular to occlusion plane. Due to clinical limitations, non-parallel implants occurred at times. The purpose of this study was focused on the bony stress distribution of different implant tilting under masticatory load. Furthermore, attempted to find the desirable installation angle of implant.
The three-dimensional finite element models were constructed to simulate when mandibular first and second molar missing restored with implants. According to different angulation designs (15□), nine solid models were built up. A simulating load (200N) was applied vertically、 horizontally(buccal-lingual direction) and obliquely45°（B-L direction and mesial-distal direction) on the occlusal central fossa of the bridge prostheses.
Implant bodies tilting with the bridge prostheses not all got bad results. For stress distribution, some designs will be better than parallel installation. From the peak stress values , slightly divergent installed implants have near(model 2) or lower values (model 5&6); slightly convergent installed implants got higher values under vertical force. Under horizontal force, the peak values were close to each other, except the 2nd implant incline distally (model 4&9) .Under the oblique force of buccal-lingual direction, the results were similar to the horizontal force; the oblique force of mesial and distal direction, slightly divergent installed implants had lower values (model 2,5&6),the others had worse results than parallel installed implants (model 1).
Clinically, there are many reasons to explain why implant tilting occur, especially over posterior area. Slightly non-parallel installation of implant bodies is may be a better choice. We suggested the clinician to install the implant over the second molar area first and check X ray first to decide the next step, and check another X ray after installing the other implant over the first molar area to get prognosis.
|
|---|
