Clinical evaluation on effects of functional muscular equal pressure zone on complete denture / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the clinical effect of the functional muscular equal pressure zone on complete denture.</p><p><b>METHODS</b>Artificial teeth were arranged within the functional muscular equal pressure zone. With this technique 35 complete dentures were made to rehabilitate 35 edentulous patients whose alveolar bones were moderately or seriously absorbed. After three months' following up, the satisfaction of these patients were investigate.</p><p><b>RESULTS</b>After prosthesis treatment, 35 patients enunciated well and the aesthetic effect was favorable. 89 percent of these patients satisfied the retention and the stability of the maxillary denture, and 78 percent satisfied the retention and the stability of the mandibular denture. 79.5 percent of these patients satisfied the mastication efficiency.</p><p><b>CONCLUSION</b>With the technique, the complete denture is fairly stable in patient's mouth. The technique can enhance the denture's retention and improve the patient's mastication efficiency, especially to these whose alveolar bones are moderately or seriously absorbed. Clinically the technique is of high practical value to these edentulous patients who are difficult to be rehabilitated.</p>

Laboratory study on abutment movement of the combined clasp, the extension clasp and the telescopic crown / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the influence of three kinds of retainers on the abutment movement of removable partial dentures (RPDs) for restoring the dentition with unilateral distal-extended tooth missing.</p><p><b>METHODS</b>The combined clasp, the extension clasp and the telescopic crown were designed to retain RPDs. When food chip was masticated between dentitions, the displacement of abutments was measured by a high-sensitive-laser-transferring-detector, and then the data was statistically analyzed.</p><p><b>RESULTS</b>All of abutments showed the inclination, torsion and vertical translocation. Of them, abutments with telescopic crowns had the lowest horizontal torsion (P < 0.01) and the highest vertical translocation (P < 0.01).</p><p><b>CONCLUSIONS</b>Compared with the combined clasp and the extension clasp, the telescopic crowns enable abutments to bear the load more axial and the stress to be distributed more even, so the design of the telescopic crown may be considered more favourable for the health of abutments.</p>

The influence of different inclination of cusp on the stress of an implant supported denture / 实用口腔医学杂志

Objective: To analyze the influence of different inclination of cusp on the stress of an implant supported denture. Methods: A spiral CT was used to scan a corpus' head.The model of mandible,teeth and implant was established by ANSYS 6.1 software. The superstructure of the denture had three different inclination of cusp.The stress distribution of the models under loading was analyzed. Results: When bearing non central loading, the maximum equivalent stress (max EQV) of the abutment was situated at the first screw of the abutment.When bearing central loading, the maximum equivalent stress(max EQV) of the abutment was situated at the cervix. Under all loading, the max EQV of the implant was situated at the cervix, the max EQV of mandible was situated at the upper cortical layer around the cervix of the implant. Higher inclination of cusp and non central loading lead to higher stress. Conclusion: The location of the max EQV of the abutment is consistent with the location of the abutment fracture; lower inclination of cusp and flatsurface teeth are benefit to the stress distribution of the implantation.