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71.
The purpose of this study was to examine how patients perceived the professionalism of University of Minnesota School of Dentistry students, faculty, and staff. Professionalism is defined by the authors as an image that will promote a successful relationship with the patient. Patients within comprehensive care clinics were asked to assess physical attributes and behaviors of the dental care providers using a questionnaire. The patients read statements dealing with characteristics of the dental care providers and responded as to whether they agreed, were neutral, or disagreed with the statement. The surveyed population consisted of 103 males and 97 females, 64 percent of whom lacked insurance coverage. Fifty-one percent of the patients were between the ages of forty-four and sixty-nine, but the overall age distribution was dispersed over a range of eighteen to one hundred. Our research found that all dental care providers displayed a professional appearance as well as behavior. The attire of the dental care provider affected the comfort and anxiety levels of patients, as did first impressions of both students and faculty. Most patients reported that students and faculty displayed effective time management and used appropriate language during the appointment. Finally, hairstyle, makeup, and jewelry appeared to have little effect on patients' opinions of the various dental care providers.  相似文献   
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PURPOSE: This study was conducted to evaluate the effect of selected disinfectants incorporated in the liquid of dental stones on material strength properties with the aim of developing a material with acceptable mechanical properties. MATERIALS AND METHODS: Two types of dental stone (types III and V) were mixed with aqueous solutions of 0.525% sodium hypochlorite, 0.1% and 10% povidone-iodine, and 2% glutaraldehyde, and with water as a control. The liquid/powder ratios recommended by the manufacturer were used. These materials were subjected to further modification by adding a mixture of 1.0% gum arabic and 0.132% calcium hydroxide to the hemihydrate powders before mixing with the disinfectant solutions at 2 different liquid/powder ratios for each. Both the regular and the modified materials were tested for compressive and diametral tensile strength after 1 hour and 1 week from the start of the mix. The structure of set materials was determined by scanning electron microscopy examination of fracture surfaces. RESULTS: The disinfectants often reduced the strength of both types of dental stone. However, using either 0.1% povidone-iodine or 0.525% sodium hypochlorite resulted in strength values comparable with that of the control. The addition of gum arabic and calcium hydroxide helped reduce the mixing liquid/powder ratios, improving the strength properties of the disinfected materials. CONCLUSIONS: Chemical disinfectants reduce the strength of dental gypsum when used as mixing water substitutes. Gum arabic and calcium hydroxide additives permit a lower liquid/powder ratio and can help offset this weakening.  相似文献   
75.
An examination of 5616 endodontically treated and retreated maxillary first and second molars was made in an attempt to determine the percentage of MB2 canals that could be located routinely, and evaluate if there were any significant differences between initial treatments and retreatments. The teeth examined were 3578 first molars and 2038 second molars treated consecutively over a 5-yr period by six endodontists. Overall the MB2 canal was found in 2133 (60%) first molars, and 712 (35%) second molars. The incidence of a MB2 canal in first molar retreatments was 66% compared to a 58% incidence in initial treatments. Whereas in second molars the retreatment incidence was 40% compared to 34% in initial treatments. The significant difference in the incidence of a MB2 canal between initial treatments and retreatments suggests that failure to find and treat existing MB2 canals will decrease the long-term prognosis.  相似文献   
76.
BACKGROUND: Growth factors are generally accepted to be essential mediators of tissue repair via well-established mechanisms of action that include stimulatory effects on angiogenesis and cellular proliferation, ingrowth, differentiation, and matrix biosynthesis. The aim of this study was to evaluate in a large-scale, prospective, blinded, and randomized controlled clinical trial the safety and effectiveness of purified recombinant human platelet-derived growth factor (rhPDGF-BB) mixed with a synthetic beta-tricalcium phosphate (beta-TCP) matrix for the treatment of advanced periodontal osseous defects at 6 months of healing. METHODS: Eleven clinical centers enrolled 180 subjects, each requiring surgical treatment of a 4 mm or greater intrabony periodontal defect and meeting all inclusion and exclusion criteria. Subjects were randomized into one of three treatment groups: 1) beta-TCP + 0.3 mg/ml rhPDGF-BB in buffer; 2) beta-TCP + 1.0 mg/ml rhPDGF-BB in buffer; and 3) beta-TCP + buffer (active control). Safety data were assessed by the frequency and severity of adverse events. Effectiveness measurements included clinical attachment levels (CAL) and gingival recession (GR) measured clinically and linear bone growth (LBG) and percent bone fill (% BF) as assessed radiographically by an independent centralized radiology review center. The area under the curve (AUC), an assessment of the rate of healing, was also calculated for CAL measurements. The surgeons, clinical and radiographic evaluators, patients, and study sponsor were all masked with respect to treatment groups. RESULTS: CAL gain was significantly greater at 3 months for group 1 (rhPDGF 0.3 mg/ml) compared to group 3 (beta-TCP + buffer) (3.8 versus 3.3 mm; P = 0.032), although by 6 months, this finding was not statistically significant (P = 0.11). This early acceleration of CAL gain led to group 1 exhibiting a significantly greater rate of CAL gain between baseline and 6 months than group 3 as assessed by the AUC (68.4- versus 60.1-mm weeks; P = 0.033). rhPDGF (0.3 mg/ml)-treated sites also had significantly greater linear bone gain (2.6 versus 0.9 mm, respectively; P < 0.001) and percent defect fill (57% versus 18%, respectively; P < 0.001) than the sites receiving the bone substitute with buffer at 6 months. There was less GR at 3 months in group 1 compared to group 3 (P = 0.04); at 6 months, GR for group 1 remained unchanged, whereas there was a slight gain in gingival height for group 3 resulting in comparable GR. There were no serious adverse events attributable to any of the treatments. CONCLUSIONS: To our knowledge, this study is the largest prospective, randomized, triple-blinded, and controlled pivotal clinical trial reported to date assessing a putative periodontal regenerative and wound healing therapy. The study demonstrated that the use of rhPDGF-BB was safe and effective in the treatment of periodontal osseous defects. Treatment with rhPDGF-BB stimulated a significant increase in the rate of CAL gain, reduced gingival recession at 3 months post-surgery, and improved bone fill as compared to a beta-TCP bone substitute at 6 months.  相似文献   
77.
Bahcall JK  Carp S  Miner M  Skidmore L 《Dentistry today》2005,24(11):74, 76, 78-80; quiz 80
Complications can occur during many dental procedures. The prepared clinician responds by either correcting the problem during treatment, or, ideally, preventing the problem from occurring in the first place. In endodontic treatment separated rotary Ni-Ti files are a common procedural problem. Through understanding that the main causes of file breakage are cyclic fatigue and torsional stress, a dentist can best prevent this occurrence by using hand files before rotary files, creating a straight-line (glide path) access into a canal, and preflaring the coronal portion before using rotary files in the apical third of the canal. In addition, using an up and down motion with the electric slow-speed handpiece (not allowing the file to bind within the canal) will significantly reduce the incidence of file breakage. If a file does break, successful removal primarily depends on the location of the file in the canal rather than the specific technique employed for removal. A case does not necessarily fail if the separated file cannot be removed. The prognosis when file separation occurs can still be favorable, especially if care was taken to reduce the critical concentration of canal debris with hand instrumentation and chemical irrigation prior to rotary file insertion. In addition, the introduction of a new CS file design will help the dentist increase the chance of removing the file in the event of breakage.  相似文献   
78.
Template fabrication for a midpalatal orthodontic implant: technical note   总被引:2,自引:0,他引:2  
An implant has been developed as an adjunct to conventional orthodontic anchorage. Planning is advisable to determine the available bone and soft tissue thickness and the optimum position for orthodontic utilization. A simple method is described for fabrication of a radiographic and surgical template to aid in optimal placement of the implant.  相似文献   
79.
Recent advances in subperiosteal implant surgery of the mandible and maxilla are described in terms of changes in implant design, use of particulate autogenous marrow cancellous bone in conjunction with subperiosteal implant to structurally rebuild marked deficient mandibles at the time the implant is placed, and the of computerized tomography to develop a three-dimensional model for the construction of implant framework, eliminating the direct bone impression surgery. The latter procedure has revolutionized the use of subperiosteal implants. These techniques are outlined, and areas of future research in use of implants in structurally deficient areas are described.  相似文献   
80.
Evaluation of alveolar bone grafting: a survey of ACPA teams.   总被引:5,自引:0,他引:5  
OBJECTIVE: To evaluate the management of alveolar clefts by cleft palate and craniofacial teams in North America. DESIGN: An anonymous survey was mailed to 240 American Cleft Palate- Craniofacial Association teams across North America regarding alveolar bone grafting. The questionnaire included multiple questions about each team's approach to alveolar bone grafting and options for the missing tooth. RESULTS: Consensus was achieved in three areas: 90% of centers performed secondary alveolar bone grafting, 78% performed grafting between ages 6 and 9 years, and iliac crest donor site was the most popular site (83%). There was no consensus with respect to dental criteria for the timing of grafting, follow-up x-rays, or the use of a grading system for evaluating results. In addition, there was no consensus on the management of the missing tooth. CONCLUSION: There is wide acceptance of secondary bone grafting and there is a consensus for the age of grafting (6 to 9 years) and donor site (iliac crest). The disturbing finding was the lack of postoperative x-ray evaluation of the results. With so much variability in management, the use of a routine, standardized scale to measure postoperative results would allow for better outcome studies in alveolar bone grafting.  相似文献   
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