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41.
M. Elizabeth Bennett PhD ; Christine Michaels MA DMD ; Kevin O'Brien MSc BDS FDS DOrth ; Robert Weyant DMD DrPH ; Ceib Phillips MPH PhD ; Katherine Dryland Vig BDS MS FDS DOrth 《Journal of public health dentistry》1997,57(4):215-223
Objectives : Few studies have examined what parents and orthodontists expect from and value about orthodontic treatment. In this study, we designed and tested a questionnaire to outline what drives consumer demand for children's orthodontic care. Further, we present data from the questionnaire to illustrate how expectations and values pertaining to orthodontic treatment relate to sociodemographic variables. Methods : Subjects were 220 Pennsylvania orthodontists and 220 parents at a university orthodontic clinic who were administered a questionnaire designed to assess what parents and orthodontists value about and expect from orthodontic treatment. Items for the questionnaire were developed via a qualitative, telephone interview process. Data were analyzed using factor analysis and reliability analysis for scale development, and analysis of variance for preliminary validity assessment. Results : Through factor analysis, the questionnaire was reduced from 84 to 52 items, and eight scales were examined: expected treatment benefits, expected treatment risks (short- and long-term), expected treatment inconveniences, value of treatment benefits, value of risks (short- and long-term), and value of treatment inconveniences. For parents, the reliability for all scales was in the acceptable range. For orthodontists, only the “short-term risks” scale failed to attain an acceptable reliability. Preliminary validity was assessed through examining relationships between demographic variables and subscale scores. For parents, income, father's education level, and sex of respondent were related to treatment expectations and values. For orthodontists, age, sex, and patient volume were related to treatment values. Conclusions : The questionnaire developed in the present study was found to be practical and reliable for use with providers and consumers of orthodontic care and can be used to explore factors affecting the demand for orthodontic care. Implications of possible unrealistic treatment expectations on the part of orthodontists and parents also are discussed. 相似文献
42.
Zhaokun Yu Judith M. Strutz DDS MSEd † Victor Kipnis PhD ‡ Shane N. White BDentSc MS MA § 《Journal of prosthodontics》1995,4(4):251-255
Purpose Reduced cement film thicknesses can improve crown seating and decrease marginal discrepancies. Improved marginal adaptation has the potential to reduce plaque accumulation, periodontal disease, and cement dissolution. Studies have indicated that dynamic seating methods can reduce seating discrepancies associated with zinc phosphate and resin cements. However, other types of cements and other dynamic techniques have not yet been studied or compared, nor has the mechanism for improved seating been fully explained. Therefore, the purpose of this study was to investigate the effect of a variety of loading methods on the film thicknesses of current types of crown and fixed partial denture cements compressed between glass plates. Materials and Methods This study investigated the effect of three dynamic loading methods on film thickness of six representative fixed prosthodontic cements. These included zinc phosphate, resin-modified glass ionomer, encapsulated glass ionomer, adhesive composite resin, composite resin, and polycarboxylate. The method was derived from American Dental Association specifications for cement film thickness. In control groups, the cements were placed between two glass plates and statically loaded with a 15-kg weight. The test groups were initially similarly loaded, and then for 30 seconds further subjected to simulated repeated patient opening and closing, vibrations from an electromallet, or an ultrasonic device. Results Mean film thicknesses ranged from 7.4 μm for polycarboxylate/ultrasound up to 40.3 μm for composite resin/static. Two-way analysis of variance revealed that the effects of material type and cementation method and their interaction all significantly affected film thickness (P < .0001). Multiple range analysis showed that dynamic methods were generally superior to static loading and that the ultrasonic method was the best overall. Conclusions The different dynamic loading methods all significantly decreased cement film thicknesses between glass plates. The ultrasonic method was the most effective. The type of cement used also influenced film thickness. Composite resins were more affected than other materials. 相似文献
43.
自体骨髓干细胞移植狗牙周缺损处引导组织再生的实验观察 总被引:4,自引:0,他引:4
目的本文对应用自体骨髓干细胞移植引导组织再生的动物实验的观察进行评价。方法6只成年狗,实验组,对照组各18颗牙。分别在每条狗抽取骨髓1ml,在实验室内进行原代骨髓干细胞培养,培养液为内含15%小牛血清(FCS)和0.5%青-链霉素抗生素的a-MEM培养液。第1代细胞转移到18块大小为6×2mm2胶原膜上,约每张胶原膜上1×107个细胞,培养24小时后相差显微镜下观察细胞在膜上附着情况。在人工制造的牙周缺损中进行体外培养的自体骨髓干细胞移植结合GTR方法(实验组)和单纯GTR方法(对照组)。在6周后切片行牙周组织学观察。结果实验组新生牙槽骨新生牙周膜组织及新生牙骨质的修复再生的效果明显好于对照组(P<0.05),形成了的牙周结构,只是引导再生的牙周组织基本恢复到正常的牙周组织高度。实验组牙槽骨再生高度平均为4.50±0.13mm;对照组为3.09±0.28mm。结论应用自体骨髓干细胞移植结合e-pTFE膜引导牙周组织再生可促进牙周组织的再生、加快正常骨结构组织的建立并缩短修复再生时间。 相似文献
44.
上颌前牙区种植修复5年临床疗效观察 总被引:1,自引:0,他引:1
目的:评估上颌前牙区种植义齿应用5年的临床效果.方法:2002年1月至2006年12月间,行上颌前牙区种植治疗患者234例,共植人种植体354颗.随访7~62个月,观察方法为X线片、临床检查及患者满意度调查.应用SPSS13.0软件包统计分析上颌前牙区种植义齿5年累计存留率(寿命表法),骨吸收情况(方差分析),软组织及美学效果.结果:上颌前牙区种植义齿5年累计存留率为97.9%;不同术式下种植体存留率无显著差异(P=1.00):种植体周垂直骨吸收量各年份相比无显著差异(P=0.88);19.8%的患者牙问乳头达到Jemt分级3分.91.7%患者对种植修复表示满意.结论:上颌前牙区行种植修复是有效的治疗方法. 相似文献
45.
腭隐裂患者头颅侧位X线片测量分析 总被引:2,自引:0,他引:2
目的 应用回顾性研究的方法对 50例腭隐裂患者X线片测量并与健康对照组对比分析 ,观察软腭在形态学、运动能力以及腭帆提肌附着位置等方面的特点 ,进一步研究腭隐裂患者腭咽闭合不全的原因 ,为其诊断提供依据。方法 腭隐裂患者 50例 (年龄 4~ 51岁 ,平均年龄 1 1 9岁 ,男性 2 0例 ,女性 30例 ,男∶女 =1∶1 5)。对术前头颅侧位定位X线片共 1 0 0张 (每例静止及发“i”音各 1张 )进行测量分析。结果 腭隐裂组的软腭相对长度较对照组短 ,患者的腭帆提肌附着点相对位置比对照组靠前 ,发音时软腭抬高角度较小 ,以上 3项指标经统计学分析 ,差异有显著性 (P <0 0 5)。两组间硬腭相对长度和发音时软腭伸长量的比较差异无显著性 (P >0 0 5)。结论 通过测量所得指标(包括软腭相对长度、腭帆提肌附着位置及发音时软腭抬高角度 )是诊断腭隐裂的重要指标 相似文献
46.
全冠边缘材料与位置对人牙周组织的影响 总被引:1,自引:0,他引:1
目的 探讨全冠边缘材料和位置对人牙周组织的影响.方法 对需作全冠或双端固定桥修复并符合纳入标准的20例患者的30颗牙,在牙体预备前、全冠或双端固定桥黏固后7~8周,分别记录其颊侧牙龈的菌斑指数(PLI)、牙周探诊深度(PD)、龈沟出血指数(SBI),并测量其龈沟液(GCF)量、龈沟液的天冬氨酸转氨酶活性(AST活性).全冠或固定桥黏固前后分别测量冠边缘间隙.暂时冠和全冠黏固后对患者各行1次口腔健康教育.结果 全冠黏固后7~8周,全冠对应牙龈的PD、 SBI≥2频率、GCF量及AST活性没有明显变化, PLI≥1的频率明显下降.结论 具有良好的口腔卫生习惯、制作精良的全冠黏固后7~8周,金属边缘、烤瓷边缘、平龈冠边缘、龈下冠边缘均不会引起人牙龈的不良反应. 相似文献
47.
48.
David N. Firtell DDS MA Jack H. Koumjian DDS MSD 《The Journal of prosthetic dentistry》1992,67(6):801-804
Some authors have stated that wax cannot be used to make impressions for complete dentures, while others have found that wax has some advantages over elastomeric impression materials. The purpose of this study was to compare mandibular impressions made with a fluid wax to those made with light-body polysulfide rubber. Fifteen maxillary and mandibular complete dentures were made using fluid wax as a final impression material. For comparison, 15 maxillary and mandibular complete dentures were made using light-body polysulfide rubber. The number of adjustments required over 1 year was recorded. No statistical difference in adjustments was noted between the two groups. 相似文献
49.
Arnaud Gleizal Laurent Kodjikian Frédérique Lebreton Jean-Luc Beziat 《Journal of cranio-maxillo-facial surgery》2005,33(3):201-204
Malignant melanoma of the lacrimal sac is rare, and only 21 cases have been reported in the world literature. They have an insidious onset and may look like chronic dacryocystitis. In only 6 of these cases were there no recurrences. In most of the survivors, the diagnosis was made early which appears to be the most important prognostic factor. Hence a CT-scan in cases of persistent dacryocystitis is important. Melanoma of the lacrimal duct system is a good example of a condition requiring a multidisciplinary approach between ophthalmologist and maxillofacial surgeon. Any persistently symptomatic lacrimal duct system may need a maxillofacial consultation. 相似文献
50.