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961.
BACKGROUNDClinical femoral neck fracture is common. Based on patient age and fracture type, different surgical methods can be selected, including cannulated screw fixation of the femoral neck and artificial total hip joint or semi-hip joint replacement. When patients with femoral neck fracture are treated with cannulated screw fixation, a cannulated screw may be positioned too deep. The excessively deep-placed screw is difficult to remove and causes major trauma to the patient.CASE SUMMARYA patient with poliomyelitis and femoral neck fracture was treated with a cannulated screw that was placed too deep. A self-made auxiliary tool (made of a steel sternal wire) was used to remove the cannulated screw near the pelvic cavity.CONCLUSIONThe depth of the cannulated screw can be estimated before screw placement using an improved hollow screwdriver with a scale mark, thus improving the safety of screw placement and facilitating clinical use.  相似文献   
962.
963.
《Journal of endodontics》2020,46(3):425-430
IntroductionThe purpose of this study was to investigate the influence of both polymerization cycles and mechanical exposure procedures on the adhesion of instrument fragments using a modified tube technique with a light-curing composite.MethodsEighty Mtwo instruments (size 15.05; VDW, Munich, Germany) were cut at a diameter of 35/100 mm and clamped in a vice with an overlap of 2 mm. Matching cannulas were filled with SDR composite (Dentsply, York, PA) and placed over the instruments. Prime & Bond Active (Dentsply Sirona, Bensheim, Germany) was used as the bonding material. Glass fiber was inserted from the opposite side into the cannula, and 1, 2, 4, or 6 polymerization cycles of 30 seconds were applied (800 mW/mm2) (n = 20/group). Sixty further identical instruments (n = 20/group) were divided into the following groups: group 1, cut at 10 mm and left unprepared (taper = 5%); group 2, parallelized using diamond instruments (taper = 0%); and group 3, prepared in a way that an inverted conical taper resulted (taper = 2%). Polymerization was performed for 2 minutes. The failure load and mode of failure were determined using a tensile testing device (2 mm/min). Data were statistically analyzed using the Kruskal-Wallis or chi-square test.ResultsThe failure load increased significantly with the number of polymerization cycles (P < .0001). More than 4 polymerization cycles had no further benefit (P > .05). The failure load in the inverted conical group was significantly lower (P < .0001) compared with the parallel and the unprepared groups. Adhesive failure was significantly more frequent in groups 2 and 3 (20/20) than in group 1 (16/20) (P < .05).ConclusionsBoth the number of polymerization cycles and the mechanical exposure procedures had a significant impact on the adhesive force when using the tube technique.  相似文献   
964.
《Journal of endodontics》2020,46(8):1059-1066
IntroductionThe purpose of this in vivo study was to evaluate the accuracy of small-volume cone-beam computed tomographic (CBCT) imaging compared with conventional periapical radiography (CPR) in the diagnosis of vertical root fractures (VRFs) using exploratory surgery as the reference standard.MethodsEighty-two dental records of 85 teeth with suspected VRFs that underwent CPR, CBCT imaging, and exploratory surgery were included. Two observers assessed CPR and CBCT images independently for the presence or absence of root fractures, and findings from the exploratory surgery were considered the reference standard. Diagnostic sensitivity, specificity, accuracy, and the receiver operating characteristic curve values were obtained. The effect of single- and multirooted teeth on diagnostic accuracy as well as the association between clinical symptoms and the presence of VRFs were also assessed.ResultsVRFs were surgically detected in 64 of the 85 teeth (75.3%), of which 62.5% were multirooted and 76.6% had intracanal posts. CBCT imaging was more sensitive and accurate (65.6% and 64%) than CPR (27.3% and 40.5%). Both CPR and CBCT diagnostic accuracies were higher in single- than multirooted teeth. Pain on percussion, a localized periodontal pocket, and tooth mobility were associated with the presence of VRFs (P < .05; odds ratio = 4.15, 13.5 and 4.1, respectively).ConclusionsThe accuracy of CBCT imaging for the diagnosis of VRFs was poor, although it was higher than with CPR. Multirooted teeth in the presence of intracanal posts may limit its diagnostic value.  相似文献   
965.
《Journal of endodontics》2020,46(9):1204-1209
IntroductionThe aim of this multicentric prospective study was to evaluate the clinical and radiographic outcomes of Biodentine (BD) pulpotomies on permanent teeth with complicated crown fractures.MethodsThis study was carried out in 2 hospital-based dental departments in Quebec, Canada. Children seeking emergency care after trauma to anterior permanent teeth were invited to participate in this study. The treatment outcome was assessed clinically and radiographically at 1 week and 1, 3, 6, 12, 18, and 24 months after treatment.ResultsForty-five patients between the ages of 8 and 16 years (mean, 10.8 ± 2.4) were included in this study. Fifty-one teeth were treated with a BD pulpotomy. The study showed a survival rate of 100% and a success rate of 91%. Four failures were noted at 1-, 6-, and 15-month follow-up, and the teeth were subsequently treated with either conventional root canal therapy or regenerative endodontic procedure. Dental sensitivity to cold reported by patients reduced over time, and more teeth responded normally to pulp vitality tests during the course of this study. Slight discoloration was noted on 8 teeth (17%). Radiographic outcomes showed dentinal bridge formation in 91% of cases, and all immature teeth showed continued root formation.ConclusionsBD is a suitable material for pulpotomies on anterior permanent teeth with complicated crown fractures. It may be a good alternative to mineral trioxide aggregate pulpotomies because it does not cause significant discoloration, and it allows root maturation.  相似文献   
966.
967.
《Saudi Dental Journal》2020,32(5):242-249
PurposeThe aim of the present study was to analyze the prevalence, causes, and patterns of maxillofacial fractures retrospectively in patients who were treated at Prince Sultan Military Medical City, Riyadh, Saudi Arabia.MethodsPatients′ medical records were reviewed from 2005 to 2014. Patient′s age, gender, cause, and the pattern of maxillofacial fractures were studied. Associated body injuries were also recorded.ResultsOut of 263 patients, 207 (78.7%) were male and 56 (21.3%) were female. The age range was from 3 to 67 yr with a mean age of 26.21 yr. Road traffic accidents 236 (89.8%) were the most commonly reported cause of maxillofacial fractures, followed by falls 14 (5.3%), assaults 4 (1.5%), gunshot 3 (1.1%), and sport accidents 2 (0.8%). Most of the cases of maxillary fracture were Le Fort II 27 (36.5%), followed by LeFort I 23 (31.1%), LeFort III 20 (27.0%) and palatal fractures 4 (5.4%). Of the mandibular fractures, parasymphysis fractures constituted 61 (27.4%), body 50 (22.4%), condyle 45 (20.2%), angle 40 (17.9%), symphysis 16 (7.2%), ramus 7 (3.1%) and coronoid 4 (1.8%). Zygomatic complex fractures 110 (94.8%) were the most commonly reported fractures in the mid and upper facial region. Other facial fractures included orbital floor 61 (97.0%), naso-orbito-ethmoidal 18 (19.8%), and frontal 12 (13.2%).ConclusionRoad traffic accidents were the most common cause of maxillofacial fractures. Spreading awareness among young drivers regarding road safety regulations is highly recommended.  相似文献   
968.
969.
Avulsion of permanent teeth is one of the most serious dental injuries. Prompt and correct emergency management is essential for attaining the best outcome after this injury. The International Association of Dental Traumatology (IADT) has developed these Guidelines as a consensus statement after a comprehensive review of the dental literature and working group discussions. It represents the current best evidence and practice based on that literature search and expert opinions. Experienced researchers and clinicians from various specialties and the general dentistry community were included in the working group. In cases where the published data did not appear conclusive, recommendations were based on consensus opinions or majority decisions of the working group. They were then reviewed and approved by the members of the IADT Board of Directors. The purpose of these Guidelines is to provide clinicians with the most widely accepted and scientifically plausible approaches for the immediate or urgent care of avulsed permanent teeth. The IADT does not, and cannot, guarantee favorable outcomes from adherence to the Guidelines. However, the IADT believes that their application can maximize the probability of favorable outcomes.  相似文献   
970.
Traumatic dental injuries (TDIs) occur most frequently in children and young adults. Older adults also suffer TDIs but at significantly lower rates than individuals in the younger cohorts. Luxation injuries are the most common TDIs in the primary dentition, whereas crown fractures are more commonly reported for the permanent teeth. Proper diagnosis, treatment planning and follow up are very important to assure a favorable outcome. These updates of the International Association of Dental Traumatology's (IADT) Guidelines include a comprehensive review of the current dental literature using EMBASE, MEDLINE, PUBMED, Scopus, and Cochrane Databases for Systematic Reviews searches from 1996 to 2019 and a search of the journal Dental Traumatology from 2000 to 2019. The goal of these guidelines is to provide information for the immediate or urgent care of TDIs. It is understood that some follow‐up treatment may require secondary and tertiary interventions involving dental and medical specialists with experience in dental trauma. As with previous guidelines, the current working group included experienced investigators and clinicians from various dental specialties and general practice. The current revision represents the best evidence based on the available literature and expert opinions. In cases where the published data were not conclusive, recommendations were based on the consensus opinions of the working group. They were then reviewed and approved by the members of the IADT Board of Directors. It is understood that guidelines are to be applied using careful evaluation of the specific clinical circumstances, the clinician's judgment, and the patient's characteristics, including the probability of compliance, finances and a clear understanding of the immediate and long‐term outcomes of the various treatment options vs non‐treatment. The IADT does not, and cannot, guarantee favorable outcomes from adherence to the Guidelines. However, the IADT believes that their application can maximize the probability of favorable outcomes.  相似文献   
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