To evaluate clinically and radiographically an alveolar ridge, preservation technique with deproteinized bovine bone graft and absorbable collagen membrane and then restoration with delayed implants were done. The study included 30 patients. The trial group's sockets were filled with deproteinized bovine bone graft (Bio-Oss) and covered with absorbable collagen membrane (Bio-Gide). The control group's sockets healed without any treatment. Panoramic radiograph and computed tomography were taken immediately after graft and 3 and 6 months later to evaluate the height, width, and volume change of the alveolar ridge bone. Dental implants were inserted in all sockets at 6 months, and osseointegration condition was evaluated in the following 12 months. All sockets healed uneventfully. In the trial group, the mean (SD) height reduction of the alveolar ridge bone was 1.05 (0.24) mm at 3 months and 1.54 (0.25) mm at 6 months. The width reduction was 1.11 (0.13) mm at 3 months and 1.84 (0.35) mm at 6 months. Bone volume reduction was 193.79 (21.47) mm at 3 months and 262.06 (33.08) mm at 6 months. At the same trend, in the control group, the bone height reduction was 2.12 (0.15) mm at 3 months and 3.26 (0.29) mm at 6 months. The width reduction was 2.72 (0.19) mm at 3 months and 3.56 (0.28) mm at 6 months. Bone volume reduction was 252.19 (37.21) mm at 3 months and 342.32 (36.41) mm at 6 months. There was a significant difference in alveolar ridge bone height, width, and volume reduction in the 2 groups. The osseointegration condition had no significant difference between the 2 groups. This study suggested that the deproteinized bovine bone graft and absorbable collagen membrane were beneficial to preserve the alveolar ridge bone and had no influence on the osseointegration of delayed implant.

Objectives: To review the cases of accidental aspiration and ingestion of foreign objects during dental procedure, and to emphasize the importance of thorough documentation of the accidents. Methods: A comprehensive search on (dental procedure/treatment/practice), (aspiration/inhalation), and (ingestion/ swallow) was performed for all years before 1st October 2014 available. The statistic analysis was made on the variables including journals and reported year, patients' age, gender, general conditions, dental procedure and location for procedure, foreign objects, site of involvement, possible causes, anesthesia during procedure and treatment, symptoms, treatment time and treatment modality, follow-up, and so on. Results: A total of 617 cases reported by 45 articles from 37 kinds of journals were included and analyzed. Most reports made detailed record. While some important variables were recorded incompletely, including patient's general conditions, location for procedure, clinical experience of the involving dentists, tooth position of procedure, possible causes, and anesthesia during procedure and treatment for the accident. Conclusions: Aspiration and ingestion of foreign objects are rare and risky complication during dental procedure. Each accident should have thorough documentation so as to provide enough information for the treatment and prevention.

No abstract

Objectives To determine the predictive value of pretreatment MRI texture analysis for progression-free survival (PFS) in patients with primary nasopharyngeal carcinoma (NPC). Methods Ethical approval by the institutional review board was obtained for this retrospective analysis. In 79 patients with primary NPC, texture analysis of the primary tumour was performed on pretreatment T2 and contrast-enhanced T1-weighted images (T2WIs and CE-T1WIs). The Cox proportional hazards model was used to determine the association of texture features, tumour volume and the tumour-node-metastasis (TNM) stage with PFS. Survival curves were plotted using the Kaplan-Meier method. The prognostic performance was evaluated with the receiver operating characteristic (ROC) analyses and C-index. Results Tumour volume (hazard ratio, 1.054; 95% confidence interval [CI], 1.016–1.093) and CE-T1WI-based uniformity (hazard ratio, 0; 95% CI, 0–0.001) were identified as independent predictors for PFS ( p < 0.05). Kaplan-Meier analysis showed that smaller tumour volume (less than the cut-off value, 11.699 cm 3 ) and higher CE-T1WI-based uniformity (greater than the cut-off value, 0.856) were associated with improved PFS ( p < 0.05). The combination of CE-T1WI-based uniformity with tumour volume and the overall stage predicted PFS better (area under the curve [AUC], 0.825; Cindex, 0.794) than the tumour volume (AUC, 0.659; C-index, 0.616) or the overall stage (AUC, 0.636; C-index, 0.627) did ( p < 0.05). Conclusions A texture parameter of pretreatment CE-T1WI-based uniformity improves the prediction of PFS in NPC patients. Key Points • Higher CE-T1WI-based uniformity and smaller tumour volume are predictive of improved PFS in NPC patients. • The combination of CE-T1WI-based uniformity with tumour volume and the overall stage has a better predictive ability for PFS than the tumour volume or the overall stage alone. • Pretreatment MRI texture analysis has a prognostic value for NPC patients. Electronic supplementary material The online version of this article (10.1007/s00330-018-5961-6) contains supplementary material, which is available to authorized users.