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排序方式: 共有7747条查询结果,搜索用时 15 毫秒
991.
Robert Fermergård DDS Per Åstrand DDS PhD 《Clinical implant dentistry and related research》2012,14(2):198-205
Background: The bone support for implants in the posterior part of the maxilla is often poor. This condition may be treated with augmentation of the maxillary sinus floor. The most common technique used is to elevate the sinus floor by inserting a bone graft through a window opened in the lateral antral wall. In 1994, a less‐invasive technique using osteotomes was suggested by Summers. Purpose: The aim of this study was to evaluate the clinical and radiographic outcome of implants placed in the posterior maxilla with the osteotome sinus floor elevation (OSFE) technique without grafting. Materials and Methods: The study population comprised 36 consecutive patients in whom 53 implants were inserted with the OSFE technique. The indication for sinus floor elevation was that the bone height below the maxillary sinus was considered to be 10 mm or less. Results: The mean height of the alveolar process in the intended implant sites was 6.3 ± 0.3 mm, and the mean elevation of the sinus floor was 4.4 ± 0.2 mm. Two implants in edentulous patients were lost at the 1‐year follow‐up, and one more at the 3‐year examination. The remaining 50 implants inserted were in function, giving a 3‐year cumulative survival rate of 94%. Implants used in single‐tooth replacements and in partially edentulous cases had a 100% survival rate. The marginal bone level at the time of loading of the implants was 0.1 ± 0.04 mm below the reference point. One year later, the corresponding value was 0.5 ± 0.06 mm. The mean bone loss between the two examinations was 0.4 ± 0.05 mm. At the final examination after 3 years, the mean bone level was situated 0.6 ± 0.09 mm below the reference point, indicating a nonsignificant change between 1 year and 3 years. Conclusions: The OSFE technique, without bone grafts, was found to produce predictable results in the treatment of 36 patients with restricted bone volume in the posterior part of the maxilla. 相似文献
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993.
Hakan H. Tuz DDS PhD Ercument M. Onder DDS PhD Reha S. Kisnisci DDS PhD 《American journal of orthodontics and dentofacial orthopedics》2003,123(6):620-623
The prevalence and rank of order of 4 otologic complaints in 200 temporomandibular disorder (TMD) patients, as well as the relationship between the complaints and TMD subgroups, were investigated and compared with an asymptomatic control group. No subjective otologic complaints were reported by 45 (22.5%) TMD patients; the remaining 155 (77.5%) patients had at least 1 otologic complaint. Otalgia, tinnitus, vertigo, and hearing loss were reported by 63.6%, 59.1%, 50%, and 36.4%, respectively, of the subjects with myofascial pain and dysfunction; by 46.1%, 44.2%, 32.5%, and 22% of the patients with internal derangement; and by 62.5%, 45.8%, 41.6%, and 20.8% of the patients with both myofascial pain and dysfunction and internal derangement. However, the incidence of otalgia (8%), tinnitus (26%), vertigo (14%), and hearing loss (14%) was found to be lower for the control group. Statistically, the control group had fewer otologic complaints. Patients in the TMD groups had high incidences of otologic complaints compared with the control subjects without TMD signs or symptoms. Aural symptoms in patients with internal derangement or myofascial pain and dysfunction, or their combination, were nonspecific. 相似文献
994.
Tancan Uysal DDS Faruk Ayhan Basciftci DDS MS Serdar Ü
ümez DDS PhD Zafer Sari DDS PhD Ahmet Buyukerkmen DDS 《American journal of orthodontics and dentofacial orthopedics》2003,123(6):628-632
The purpose of our study was to determine the effect of a 35% hydrogen peroxide bleaching agent on the shear bond strength of metallic orthodontic brackets. Sixty premolars were randomly divided into 3 groups of 20 each. Teeth in group A were etched with 37% phosphoric acid before bonding metallic premolar brackets. Teeth in the other 2 groups were bleached with a 35% hydrogen peroxide in-office bleaching agent according to the manufacturer's recommendations. Twenty bleached teeth (group B) were bonded immediately, and the other 20 (group C) were stored in artificial saliva for 30 days before bonding. Shear bond strength of these brackets was measured on a universal testing machine and recorded in MPa. Adhesive remnant index (ARI) scores were determined after the brackets failed. Data were analyzed with analysis of variance (ANOVA) and chi-square tests. The shear bond strength values of groups A, B, and C were 12.9 +/- 3.4, 12.0 +/- 4.6, and 14.8 +/- 4.0 MPa, respectively. Results of ANOVA showed no statistically significant differences in shear bond strengths between groups (P >.05). ARI scores were significantly different in all groups. The unbleached group's failures were primarily at the bracket/adhesive interface, whereas the bleached groups either showed cohesive failures within the adhesive or failed at the adhesive/enamel interface. The results of this study suggest that office bleaching with hydrogen peroxide does not adversely affect the bond strengths of brackets bonded immediately after bleaching or 30 days after bleaching, even though bleaching can result in differences in the failure site. 相似文献
995.
The genetics of human tooth agenesis: New discoveries for understanding dental anomalies 总被引:10,自引:0,他引:10
Heleni Vastardis DDS DMSca 《American journal of orthodontics and dentofacial orthopedics》2000,117(6):650-656
The important role of genetics has been increasingly recognized in recent years with respect to the understanding of dental anomalies, such as tooth agenesis. The lack of any real insight into the cause of this condition has led us to use a human molecular genetics approach to identify the genes perturbing normal dental development. We are reporting a strategy that can be applied to investigate the underlying cause of human tooth agenesis. Starting with a single large family presenting a clearly recognizable and well-defined form of tooth agenesis, we have identified a defective gene that affects the formation of second premolars and third molars. With the use of "the family study" method, evidence is produced showing that other genetic defects also contribute to the wide range of phenotypic variability of tooth agenesis. Identification of genetic mutations in families with tooth agenesis or other dental anomalies will enable preclinical diagnosis and permit improved orthodontic treatment. 相似文献
996.
997.
998.
Mehmet Cem Özden PhD Ali Veysel Özden DDS PhD Abdülkadir Çankaya DDS PhD Erdinç Kolay PhD Sami Yıldırım DDS PhD 《Cranio : the journal of craniomandibular practice》2020,38(5):305-311
ABSTRACT
Objective
This randomized, single-center clinical trial aimed to compare the efficacy of superficial dry needling (SDN) and deep dry needling (DDN) in patients with myofascial temporomandibular disorder (MTMD) related to the masseter muscle.Methods: Forty patients showing MTMD with trigger points in the masseter muscle were randomly assigned to groups. Dry needling of the masseter muscle was performed once per week for three weeks. Pressure pain threshold (PPT) measurements, visual analog scale scores, and maximal jaw opening were assessed.Results: Both patient groups showed significant pain reduction, but the SDN group showed significantly better pain reduction. The PPT measurements obtained in the follow-up examinations at three and six weeks were significantly better than the values in SDN and DDN groups.Discussion: SDN showed better pain-reduction efficacy in patients with MTMD. Further research with a larger size sample and a longer follow-up period will help elucidate the benefits of SDN. 相似文献999.
1000.