الفهرس | Only 14 pages are availabe for public view |
Abstract Seven patients were selected for this study. Patients were having edentulous maxilla. Two restorable canines having adequate bone support were only the remaining natural teeth in the lower ridge. Root canal treatment was carried out to the 2 remaining lower canines. The crowns were reduced to 1-2 mm above the free gingival margin and contoured to a dome shape preparation. Upper conventional complete upper denture and lower complete tooth supported overdenture were constructed for each patient. The EMG activity of masseter and temporalis muscles was recorded for each patient during maximum clinching and eating soft food (banana). The root canals of the two abutments were prepared to receive the post part of the ball attachment. Impression was made for the seated castable posts in the root canals. Construction of the attachment (post, coping and ball head) was done and cemented in the patient mouth. The metal housings with the rubber o-rings were seated on the ball heads of the attachment. Relief of the fitting surface of the lower denture was done opposite to the the two metal housings using an acrylic bur. The relieved areas were filled with pink, fast cold-cure acrylic resin mix in dough stage. The denture was inserted in the patient’s mouth and the patient was instructed to close in maximum intercuspation till full curing of the resin to a hard set. The denture was removed, cleaned, and flash was trimmed and delivered to the patients Another EMG activity of masseter and temporalis muscles was recorded during maximum clinching and eating soft food (banana) for the tooth retained lower overdenture against the upper conventional complete denture. Surface electrodes were repositioned at the same elctrode sites using a face transparent template constructed for each patient at the end of the 1st electromyographic record. The 2nd electromyographic record was done with the same procedures and under the same circumstances of the 1st record. Data obtained from the electromyographic evaluation of the 2 masticatory muscles (masseter and temporalis) were collected, arranged, tabulated and statistically analyzed. The results of this study reviled statistical insignificant difference between the electromyographic activity of masseter and temporalis muscles for tooth supported overdentures and tooth retained overdentures during maximum clenching. However statistically significant decrease of muscle activity of the two studied muscles was recorded for the tooth retained mandibular overdenture compared with the tooth supported mandibular overdenture during chewing soft food . |