Clinical safety evaluation of contrast agents based on real-world evidence.

WHAT IS KNOWN AND OBJECTIVE: This study was aimed at comparing the adverse drug reactions (ADRs) arising from the use of iodinated contrast medium (ICM) and gadolinium-based contrast media (GBCM), and to provide a basis for the clinical selection of contrast media. METHODS: Retrospective data for ADR cases occurring from the use of ICM or GBCM during enhanced scanning in computed tomography and magnetic resonance imaging were collected between June/2013 and May/2020 from Wenling Hospital of Traditional Chinese Medicine. Chi-square tests were performed based on the characteristics of patients and the classification of contrast medium. Bonferroni correction was applied to the statistical analyses with multiple comparisons of proportions. RESULTS: Among 27,328 patients who were subjected to enhanced CT scanning, 207 cases (0.76%) showed ICM-related ADRs. Among 16,381 patients who were subjected to enhanced MRI scanning, 25 cases (0.15%) showed ADRs related to GBCM. The incidence of ADR induced by GBCM was significantly lower than ICM-induced ADR (p < 0.01). There were no significant differences in the incidence among different types of ICM, including ioversol and iodixanol, as well as iodixanol from different manufacturers (p > 0.05). Interestingly, the ADR incidence of ICM seemed to be associated with gender, with a significantly higher incidence in females than in male patients, and it was also associated with the age, with a lower occurrence in older (>44 years) compared to younger patients. WHAT IS NEW AND CONCLUSION: With respect to ADR incidence, the safety profile of ICM of different types and different manufacturers was found to be similar in clinical use, warranting no need of specifically choosing imported or more expensive products. While choosing contrast medium type for clinical use, attention should be paid to certain populations, especially to younger and female patients when the patients are about to undergo a contrast-enhanced examination.

Endoscope-assisted neurectomy and inferior alveolar nerve avulsion in treating trigeminal neuralgia.

OBJECTIVE: To explore endoscope-assisted surgical treatment for idiopathic trigeminal neuralgia (TN), with neurectomy and avulsion of the inferior alveolar nerve (IAN), when patients are not willing to undergo intracranial procedures. CLINICAL MATERIALS AND METHODS: Five TN patients with inferior alveolar neuralgia in the mandibular branch were admitted; endoscope-assisted inferior alveolar neurectomy and avulsion was performed for TN treatment. Clinical observation and postoperative follow-up were conducted. RESULTS: After the operation, all patients had complete relief of pain, with mild postoperative swelling, limited mouth opening, and fast recovery. Patients were followed up for 3-24 months. Facial numbness and paresthesia were felt in the IAN distribution area of the operated side, with no recurrence. CONCLUSION: Endoscope-assisted neurectomy and avulsion of the IAN is a safe surgical method to treat TN in the mandibular branch when craniotomy is contraindicated or when patients decline neurosurgical options. It is effective in pain relief, with limited invasiveness and speedy recovery.

miR-1827 inhibits osteogenic differentiation by targeting IGF1 in MSMSCs.

We recently reported that maxillary sinus membrane stem cells (MSMSCs) have osteogenic potential. However, the biological mechanisms of bone formation remain unclear. In this study, we investigated the role and mechanisms of microRNAs (miRNAs) in the osteogenic differentiation of MSMSCs. The expression of miRNAs was determined in differentiated MSMSCs by comprehensive miRNA microarray analysis and quantitative RT-PCR (qRT-PCR). We selected miR-1827 for functional follow-up studies to explore its significance in MSMSCs. Here, miR-1827 was found to be up-regulated during osteogenic differentiation of MSMSCs. Over expression of miR-1827 inhibited osteogenic differentiation of MSMSCs in vitro, whereas the repression of miR-1827 greatly promoted cell differentiation. Further experiments confirmed that insulin-like growth factor 1 (IGF1) is a direct target of miR-1827. miR-1827 inhibited osteogenic differentiation partially via IGF1, which in turn is a positive regulator of osteogenic differentiation. Moreover, miR-1827 suppressed ectopic bone formation and silencing of miR-1827 led to increased bone formation in vivo. In summary, this study is the first to demonstrate that miR-1827 can regulate osteogenic differentiation. The increase in miR-1827 expression observed during osteogenesis is likely a negative feedback mechanism, thus offering a potential therapeutic target to address inadequate bone volume for dental implantation through inhibiting miR-1827.

Clinical application of light solidified calcium hydroxide as temporary crown adhesive / 口腔疾病防治

Objective @# To investigate the feasibility of using UV curable calcium hydroxide as temporary crown binder. @*Methods @#242 patients with temporary crown were selected and randomly divided into three groups according the order of registration week each month, and respectively underwent temporary crown cement with TempoCemNE (n = 78), Provicol (n = 80) and Calcimol LC (n = 84) for each tooth. The retention effect and the status of the gum and the pulp were observed at one week after operation.@*Results @# There was no significant difference between the three groups in the retention effect and the status of the gum and the pulp (χ12 = 5.553, P1 = 0.062 > 0.05; χ22 = 4.783, P2 = 0.091 > 0.05; χ32 = 3.290, P3 = 0.193 > 0.05). There was a good effect of temporary crown cement in three groups of TempoCemNE, Provicol and Calcimol LC.@*Conclusion @#Calcimol LC can be used as a new type of temporary crown cement with good bonding performance and the protection to gums and pulp, and simple operation.

Investigation of multipotent postnatal stem cells from human maxillary sinus membrane.

Maxillary sinus membrane (MSM) elevation is a common surgical technique for increasing bone height in the posterior maxilla prior to dental implant placement. However, the biological nature of bone regeneration in MSM remains largely unidentified. In this study, MSM tissue was obtained from 16 individuals during orthognathic surgery and used to isolate MSM stem cells (MSMSCs) by single-colony selection and STRO-1 cell sorting. The cell characteristics in terms of colony-forming ability, cell surface antigens, multi-differentiation potential and in vivo implantation were all evaluated. It was found that MSMSCs were of mesenchymal origin and positive for mesenchymal stem cell (MSC) markers such as STRO-1, CD146, CD29 and CD44; furthermore, under defined culture conditions, MSMSCs were able to form mineral deposits and differentiate into adipocytes and chondrocytes. When transplanted into immunocompromised rodents, MSMSCs showed the capacity to generate bone-like tissue and, importantly, maintain their MSC characteristics after in vivo implantation. These findings provide cellular and molecular evidence that MSM contains stem cells that show functional potential in bone regeneration for dental implant.

Treatment of alveolar cleft with distraction osteogenesis using anchorage with a tooth-microimplant joint in a dog model.

Our aim was to investigate the efficacy of correction of an alveolar cleft with distraction osteogenesis using anchorage with a tooth-microimplant joint in a canine model, which was established in 12 adult mongrel dogs that were subsequently randomised into two groups (n=6 in each). The first group comprised dogs that had osteogenesis using anchorage with a tooth (tooth group), while in the second, anchorage with tooth-microimplant joint (microimplant group) was used. All animals were killed one month after completion of distraction. Samples were collected for gross observation and histological examination. There was a significant difference in the degree of movement of the anchorage teeth in the transport discs between the 2 groups (p<0.01). There was less prominent inclination and shift of the natural teeth in the transport disc and less bony resorption around the root in the microimplant group than in the tooth group. These changes were less remarkable in the microimplant group. Treatment of alveolar cleft by distraction osteogenesis using anchorage with a tooth-microimplant joint is practical, and yields better results.

[Maxillary sinus augmentation with simultaneous implantation using guided bone regeneration].

OBJECTIVE: To investigate the effect of new bone formation in sinus augmentation with guided bone regeneration (GBR) using collagen membranes. METHODS: The first maxillary molars of 18 adult female Beagle dogs were extracted and the sinus floors of both sides were lifted with simultaneous implantation. A combination of autografts and Bio-Oss in a 2:1 ratio was placed in the space under the membrane. On the experimental side in each dog, the collagen membrane was folded at the lateral osteotomy window, the apex of the implants and a certain part of palatal bone. On the contralateral control side, the collagen membrane only covered the osteotomy window. Six animals were sacrificed at 4, 12, and 24 weeks respectively after surgery. Gross observation, biomechanical testing and histological examinations were performed. RESULTS: The translocation of grafted materials and bone absorption were found on the top of implants in the control side, and the grafted materials kept original shape at the experimental side at 4th week. The granule of Bio-oss absorbed obviously at 12th and 24th week. The pull-out force increased with time. At 24th week, the force of pull out was 558.1 ± 37.4 N at the study side, and 471.4 ± 31.5 N at the control side. There was a significant difference in the pull-out force was noted between the two groups (P < 0.01). Histological examination showed new bone formation on the sinus floor, and the grafted materials gradually reduced with time CONCLUSIONS: GBR with the enfolded-coverage of the membrane can effectively decrease absorption of the grafted materialon the apical surface of implants and stimulate new bone formation in the sinus augmentation.

Craniocervical necrotizing fasciitis of odontogenic origin with thoracic extension.

Craniocervical necrotizing fasciitis is an uncommon but aggressive infection with high morbidity and mortality. We present a case of craniocervical necrotizing fasciitis with thoracic extension caused by a dental infection in a 56-year-old man, with a successful outcome involving broad-spectrum intravenous antibiotics and an aggressive surgical debridement.

[The impact of changing the buccal position of the transported bone on early bone formation after alveolar vertical distraction].

OBJECTIVE: To assess the effects of 1-step method of changing the buccal position of the transported bone after distraction on early bone formation. METHODS: The custom-made bidirectional distraction devices were used. Total of 8 adult mongrel dogs were procured. The bilaterally mandible premolars were extracted. After 1 month, the complete osteotomy was performed and the devices were placed. The gradual distraction was started after 1 week latency at the rate of 1 mm per day, total 6 mm in height was achieved. The 1-step method of changing the buccal position of the transported bone was performed the day after the vertical distraction period in one side of the animals, and the other side as the controlled side. All animals were killed after a 7 days consolidation. The vascular system was stained post mortem carbon ink perfusion to assess possible damages. Quantitative evaluations of bone density were performed with dual-energy X-ray absorptiometry (DEXA), analysis of the ratio of vascular square was conducted in a computer. RESULTS: All animals tolerated the procedures well. After vertical distraction, the tested side can be moved 3 mm in buccal direction. DEXA examination showed that the density of the distracted bone was no statistical difference in both the tested and the controlled side. Vascular damage was not observed, and there was no statistical difference in the ratio of vascular square by analyzing the histological section in computer. CONCLUSION: In some extent, 1-step method of changing the buccal position of the transported bone after distraction can mold the regenerate bone to correct the axial displacement, without endangering early callus formation and vascularization.

Management of high-flow arteriovenous malformation in the maxillofacial region.

Management of high-flow arteriovenous malformation (AVM) in the oral and maxillofacial region, one of the greatest challenges facing oral and maxillofacial surgeons, is patient-specific in almost all cases. The aim of this study was to review our experience with superselective intra-arterial embolization followed by surgical resection and bone wax packing (BWP) of the bone cavity and curettage to manage AVM. Sixteen patients with AVM of the oral and maxillofacial region were included in this study. All patients were evaluated with preoperative angiography, and superselective intra-arterial embolization of the lesions was done in the same session by the same interventional radiologists. Forty-eight to 72 hours later, surgical resection of the soft-tissue vascular lesions and BWP of the bone cavity and curettage were performed. There were no complications related to either the preoperative angiography or the embolization procedure. The pulsation and noise were absent, and the hemorrhage disappeared. Followed up after the surgical treatment for a mean of 38 months (range, 7-63 months), 14 cases were controlled and 2 were improved, and no case was persistent or recurred. Superselective intra-arterial embolization followed by surgical resection and BWP of the bone cavity and curettage was an effective therapy in the oral and maxillofacial region.