[Review of clinical effects of disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation in 10 years].

PURPOSE: To analyze the bone remodeling around the implant 10 years after disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation and to investigate the influence of different factors on implant retention. METHODS: The clinical and imaging data of patients undergoing DSR-based sinus floor elevation with simultaneous implantation were collected from the Department of Dental Implantology, Affiliated Hospital of Qingdao University from January 2008 to December 2011. Panoramic film and CBCT were used to measure the changes of bone mass around implant in different periods. Kaplan-Meier and Log-rank tests were used to analyze the effects of different factors on implant retention with SPSS 26.0 software package. RESULTS: The study included 98 patients with a total of 128 implants. During the follow-up of 0-168 months, 7 implants failed, and the remaining formed good osseointegration and functioned, with a 10-year cumulative retention rate of 94.53%. The height of bone formation was (0.29±0.15) mm at the top and (2.74±0.66) mm in the sinus of 75 implant sites with complete imaging data obtained ten years after surgery. Kaplan-Meier and Log-rank tests showed that 8 factors including initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis had significant effects on implant retention. CONCLUSIONS: The DSR-based internal sinus floor elevation with implantation is a reliable and stable bone augmentation operation for vertical bone defect in maxillary posterior region, with a 10-year cumulative retention rate of no less than 94%. Initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis are the important factors affecting the long-term retention rate of implants.

[Effect of PRRX1 on autophagy of salivary adenoid cystic carcinoma cells].

PURPOSE: To investigate the effect of paired related homeobox1 (PRRX1) on autophagy of salivary adenoidcystic carcinoma (SACC) cells. METHODS: PRRX1-overexpressed lentiviral vectors and their negative control lentiviral vectors were used to transfect SACC cells. The transfection effect was detected by Western blot. Autophagosome was observed under transmission electron microscopy(TEM). The level of autophagy markers (LC3-II/Beclin1) was detected by immunofluorescence and Western blot. Statistical analysis was performed with SPSS 17.0 software package. RESULTS: PRRX1 protein level increased, autophagosome number decreased, and autophagy marker level decreased in the PRRX1 overexpressed group, compared to the control (P<0.05). CONCLUSIONS: PRRX1 inhibits the autophagy of SACC cells.

Modified Disk-Up Sinus Reamer for Sinus Floor Elevation and Simultaneous Implant Placement: An Animal Study with Miniature Pigs.

Objective: The disk-up sinus reamer (DSR) is a modified instrument used to elevate the maxillary sinus floor. This study aimed to compare the effects of modified DSR sinus floor elevation (DSFE) with osteotome sinus floor elevation (OSFE), both with simultaneous implant placement. Methods: Twelve miniature pigs were treated with DSFE on one side and OSFE on the other. Implants 9 mm in length were placed in six pigs without grafting, while implants 11 mm in length were placed in the other six pigs with grafting. After submerged healing for 3 months, vertical bone gain (VBG), general and histological observation, and bone contact ratio (BCR) were analyzed. Results: The mean maxillary residual bone height (RBH) when implants were placed was 6.45 ± 0.36 mm. In the no-grafting group, DSFE and OSFE had a similar VBG after 3 months. The grafting group with DSFE recorded a significantly higher VBG (VBG0: 7.83 ± 0.44 mm, VBG1: 7.54 ± 0.40 mm) than the graft group with OSFE (VBG0: 5.45 ± 0.56 mm, VBG1: 4.34 ± 2.15 mm) (p < 0.05). One implant became loose and the sinus mucosa of three pigs appeared metallic in color on the control side (OSFE). Conclusions: The effect of OSFE and DSFE is similar when there is no need for grafting. DSFE seems a better alternative method for sinus floor elevation with grafting when more VBG is needed.

[Influence of platform switching on crest bone maintenance around implants: a radiographic investigation in dogs].

PURPOSE: To evaluate and compare the dynamic changes in functional loading or non-functional loading with platform-switching (PLS) implants and butt-joint implants,and to refine the factors leading to marginal bone loss around PLS. METHODS: Six adult dogs were selected and numbered randomly.The second,third and fourth premolars in bilateral mandible of each dog were extracted. After 3 months, the implantation operation was carried out. There were 3 kinds of implants, 36 implants in total, which were divided in to 3 groups: Group A,Group G and Group U. In particular order, A, G and U were placed on each side of every dog. Three months later, the 2nd surgery was begun. At the 4th month from the 1st surgery, for each dog, on the right side only, the abutments were installed and impression was taken. Then, after 2 weeks, the dental prostheses were put on. All dogs were executed at the end of the 12th month. X-ray film was taken at the 3rd, 6th, 9th and 12th month and the moment of the 1st surgery (baseline). Measurements were made between the implant shoulder (IS),the most coronal level of bone in contact with implant (CLB), and the level of alveolar bone crest (BC). According to the different groups of implants (A, G, U), all records were analyzed with paired and Wilcoxon's signed rank test using SPSS11.5 software package. RESULTS: The mean IS-CLB and IS-BC values of group A, G were significantly different with those of group U at the 6th, 9th and 12th month, while there was no significant difference between group A and G. No matter they were loading or not, the self-comparison of each kind of implant presented no significant difference. There was no significant difference between every kind of implant on their self-comparison during the first three months; while, the differences were significant during the next 9 months. CONCLUSIONS: The most significant changes in the absorption of marginal bone around two stage submerged implant can be observed after 3 months of implanting. The bone absorption was not related to functional loading or not.

[Parotid major duct cyst: a case report].

Parotid gland cyst can be congenital or acquired, which is rarely seen in clinic. Cysts in the main duct of the parotid gland are especially rare. We reported a 37-year-old man who presented with a painless mass on the right cheek. Superficial parotidectomy was performed and histopathologic examination of the specimen revealed a main parotid duct cyst. The clinical features, diagnosis, and treatment of the case were discussed and the relevant literatures were reviewed.

[Osteoma in the soft palate: report of one case and review of the literature].

Osteoma is a benign tumor, which is composed of mature differentiated bone tissue and derived from osteoplast in periosteum endothecium. Osteomas is common in the bone in clinic, however, osteoma in the soft tissue is distinctly rare. Clinically, the lesion presents as hard, slowly growing mass with clear border. This article reported a case with soft palate osteoma. The clinical manifestation, differential diagnosis, pathologic diagnosis and treatment were discussed. Surgical resection with postoperative follow-up is suggested as the main treatment for this disease.

[Resection of carotid body tumor under interrupted block of common carotid artery].

7 patients with carotid body tumor (CBT) were evaluated by DSA preoperatively. Carotid artery (CA) blocking test was carried out under local anesthesia before operation. With CA blocked temporarily, tumors were resected under general anesthesia after the test was normal. Meanwhile some cases underwent restoration with CA repair, end-to-end anastomosis or artificial vascular grafting. No case underwent internal bypass. CA was blocked 2 to 4 times in operation. The average blocking time of CA was 22 minutes and the longest blocking time of that reached 28 minutes. The average blood loss of cases without embolization preoperatively was 1100 ml, cases with embolization was 480 ml. 3 cases had nerve complications. DSA is of important value in the diagnosis and treatments of CBT. Temporary blocking artery method can help to judge when to use internal bypass, make operation easy, decrease blood loss and nerve complications.