A comparative study of bite force associated with remaining bone level in anterior and premolar teeth at periodontal maintenance phase / 대한치주과학회지

Periodontal supporting tissue goes through destruction by chronic inflammatory periodontal disease as two aspect. One is qualitive aspect such as alteration of periodontium, the other is quantitative aspect such as alveolar bone loss. According to many authors, PDL is responsible for biting force, and there are two means for measuring PDL's function - mobility test and biting force test. This study was conducted to compare the biting force with remaining bone level, that is, quantitative aspect of periodontium, in anterior and premolar teeth at periodontal maintenance phase. 17 patients on periodontal maintenance phase during 6 months at minimum were selected for this study. For the same condition, 4 anterior, canine, premolar teeth were tested by MPM-3000 bite-force register at the same time(a.m.10-12), the same position, the same posture, by the same examiner. Patients of TMD, ill-fitting prosthesis, general disease, malocclusion and the teeth of TFO, absence of opposing teeth, malposition were excluded. Remaining bone level was measured on the panorama X-ray film through 5 level from 1mm below CEJ to root apex. Teeth were examined twice, and bigger one was selected. If the values showed large difference, examinatin was re-done and the mean was selected. The results were as follows ; 1. In the 4 anterior group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 3/5 bone level, maximal biting force is decreased significantly(p<0.01). 2. In the canine group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 2/5 bone level, maximal biting force is decreased significantly(p<0.01). 3. In the premolar group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 3/5 bone level, maximal biting force is decreased significantly(p<0.05). From the results of this study, clinicians could utilize these efficiently when they have to determine the proper restorative materials, time for tooth extraction. treatment plan, prognosis.

Biting force of upper premolar and molar in the patients with unilateral cleft lip and palate / 实用口腔医学杂志

Objective:To study the biting force of upper premolar and molar in the patients with unilateral cleft lip and palate(UCLP).Method:25 health people and 22 cases (13 male and 9 female with pemanent teeth) of UCLP without tempromandibular joint dysfuction were selected in the subject.Their biting force of upper premolar and molar in intercaspid position was tested by MBF 1 device,meanwhile,their mastictory perfomance and contact area of upper premolar and molar were checked.All of the results were managed by computer with SPSS 7.5 statistics software.Results:①Biting force of upper premolar and molar of male was higher than that of female in health people,but there was no sexual difference in UCLP.② Biting force in the group of UCLP was lower than that in the control (P