Maxillary sinus augmentation and implant placement following removal of a maxillary antral cyst: a preliminary clinical study / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the clinical outcome of maxillary sinus augmentation and implant placement following removal of a maxillary antral cyst.</p><p><b>METHODS</b>In this study 32 patients with 33 maxillary antral cysts were enrolled. The partial wall of cyst was removed through a small lateral sinus approach and cyst spontaneous shrink was expected when wall of cyst was destroyed for open drainage. Three to six months later the secondary sinus approach 1.5 mm circling the first approach for augmentation was undertaken. Dental implants were placed simultaneously or later. All patients finished prosthetic rehabilitation in the study and were followed up for (30.9 ± 11.5) months. The intraoperative and postoperative complications were recorded. The survival rate of the implants was calculated.</p><p><b>RESULTS</b>In this study, 33 maxillary antral cysts of 32 patients were removed. Maxillary sinus augmentation was performed after a mean of (4.5 ± 1.5) months (range, 2-8 months). Sixty-two implants were inserted and all patients finished prosthetic rehabilitation after a mean of (10.8 ± 2.7) months (range, 5-17 months). The survival rate of implants was 95% (59/62). Three implants failed before their prosthesis delivered due to failure of osseointegration and were reinserted later. No recurrence of cyst was observed until the last recall. In this study, 24 specimens were mucosal cysts. Five specimens were mucoceles and 4 specimens were not certain in pathology.</p><p><b>CONCLUSIONS</b>Maxillary sinus cysts have a negative effect on maxillary sinus augumentation if not removed. The present preliminary data of the study suggests that the clinical result of maxillary sinus augmentation and implant placement following removal of a maxillary antral cyst is predictable.</p>

Application of xenograft for alveolar ridge preservation in posterior sites: a randomized controlled clinical trial / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of ridge preservation with Bio-Oss Collagen and Bio-Gide in posterior sites.</p><p><b>METHODS</b>From May 2010 to July 2013, 16 patients with bilateral posterior teeth planned to be extracted and replaced by implants were enrolled. One of the sockets was randomly selected and presserved with Bio-Oss Collagen and Bio-Gide (intervention group). The contralateral socket was left to heal spontaneously (control group). Cone-beam (CBCT) scans were performed immediately after the extraction and 6 month later. The bone cores were collected during the implant placement surgery and analyzed by micro-computed tomography.</p><p><b>RESULTS</b>After 6 month healing, the vertical and horizontal dimensional alteration of the treatment group were (0.55 ± 1.05) mm and (-0.99 ± 0.94) mm respectively, while the vertical and horizontal change of control group were (-0.71 ± 1.41) mm and (-2.26 ± 1.29) mm respectively. The micro-computed tomography results showed that there was no significant difference in new bone volume between control and intervention groups.</p><p><b>CONCLUSIONS</b>Applying Bio-Oss Collagen and Bio-Gide for ridge preservation in posterior sites resulted in less vertical and horizontal bone resorption of sockets following extraction.</p>

Occlusal force and its distribution in the position of maximum intercuspation in individual normal occlusion: a cross-sectional study / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the occlusal force in the position of maximum intercuspation in the population with individual normal occlusion using a new occlusal analyzing equipment (TeeTester).</p><p><b>METHODS</b>Twenty-nine volunteers aged from 21 to 32 years were recruited. Occlusal analysis was performed using TeeTester. An arch model of each subject was retrieved in order to measure the tooth width and to calculate the force applied on each tooth.</p><p><b>RESULTS</b>The occlusal force in the position of maximum intercuspation was (900 ± 361) N (range: 335-1 727 N). The maximum occlusal force was correlated with the contacting area. The mean value of occlusal force on the molars ranged from 107 to 156 N, with the mean value on the first molar greater than that on the second molar within the same quadrant. The mean value of occlusal force ranged from 39 to 66 N on the premolars, and from 11 to 33 N on the front teeth.</p><p><b>CONCLUSIONS</b>There is a great variation of occlusal force in maximum intercuspation in individual normal occlusion. TeeTester occlusal analyzing system provides absolute occlusal force in kilogram and can be cowerted to N, which may assist clinical examination in patients.</p>