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991.
Ridgway HK Mellonig JT Cochran DL 《The International journal of periodontics & restorative dentistry》2008,28(2):171-179
This study histologically evaluated recombinant human platelet-derived growth factor-BB (rhPDGF-BB) in combination with beta-tricalcium phosphate (beta-TCP) for the treatment of human intraosseous periodontal defects. Eight patients, each with two teeth treatment planned for extraction, were enrolled. Presurgical measurements included probing depth, clinical attachment level, and recession. Initial surgery consisted of flap reflection, debridement, placement of a root notch through the base of calculus, scaling and root planing, root biomodification with 50 mg/mL tetracycline, grafting with rhPDGF-BB + beta-TCP, and complete wound closure. One tooth in each patient was treated with 0.3 mg/mL of rhPDGF-BB + beta-TCP, and the other tooth was treated with 1.0 mg/mL of rhPDGF-BB + beta-TCP. After a minimum of 6 months of healing, postsurgical clinical measurements were made, and teeth were removed en bloc. Soft tissue healing was uneventful. Histologic evaluation demonstrated new bone, cementum, and periodontal ligament coronal to the reference notch in 13 of the 16 teeth. Six of the eight 0.3-mg/mL sites and seven of the eight 1.0-mg/mL sites demonstrated periodontal regeneration. This study provides proof of principle that 0.3 mg/mL and 1.0 mg/mL of rhPDGF-BB and beta-TCP can promote periodontal regeneration in human intraosseous periodontal defects. 相似文献
992.
OBJECTIVE: To compare the costs of providing dental treatment under general anaesthesia or sedation for special needs patients. METHODS: After a Delphi exercise, a questionnaire was designed, piloted and then sent to nine NHS Trust dental service managers, within the Salaried Dental Services in the North East of England, to obtain information on the costs incurred during the treatment of special needs patients using sedation or general anaesthesia. The questionnaire related to the average number of such patients treated per session, staff costs, depreciation cost for buildings and equipment, and overhead costs including consumables and drugs. RESULTS: All nine dental service managers returned completed questionnaires. The all-inclusive cost for treatment per patient under general anaesthesia ranged from 203.65-479.50 pounds (mean cost: 285.79 pounds) and for sedation from 57.60-153.50 pounds (mean cost: 90.81 pounds). On average three special needs patients were treated per session. The greatest variation in the costs for general anaesthesia was due to staffing costs, which ranged from 1064.10 to 350.00 pounds per session across the Trusts. CONCLUSIONS: In the small number of centres sampled, the cost of delivering dental care under sedation or general anaesthesia was shown to vary widely. Overall, the mean cost of sedation was one-third that of general anaesthesia. However, the cost of both was substantial and cognisance needs to be taken of the costs of such services. 相似文献
993.
OBJECTIVES: Adhesive analysis, under the scanning electron microscope of microtensile specimens that failed through the adhesive interface, was conducted to evaluate the amount of voids present at the axial versus gingival cavity walls of class II composite restorations restored under in vivo and in vitro conditions. METHODS: Five patients received class II resin composite restorations, under in vivo and in vitro conditions. A total of 14 premolar teeth yielded 59 (n=59) microtensile adhesive specimens that fractured through the adhesive interface. The fractured surfaces of all specimens were examined and the % area of voids was measured. RESULTS: Voids at the adhesive joint were highly predictive of bond strengths. An increase in the number of voids resulted in a decrease in the microtensile bond strength. The area of voids at the adhesive interface was as follows: in vivo axial 13.6+/-25.6% (n=12); in vivo gingival 48.8+/-29.2% (n=12); in vitro axial 0.0+/-0.0% (n=19) and in vitro gingival 11.7+/-17.6% (n=16). SIGNIFICANCE: Composite resin may bond differently to dentin depending upon the amount of voids and the cavity wall involved. The bond to the gingival wall was not as reliable as the bond to the axial wall. An increase in the amount of surface voids was a major factor for reducing microtensile bond strengths of adhesive to dentin. 相似文献
994.
995.
We report the case of a woman of 34 years who had ulcerative colitis and atypical pyoderma gangrenosum. The pyoderma gangrenosum responded to conservative treatment. 相似文献
996.
997.
Estafan D David A David S Calamia J 《Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)》1999,20(6):555-60; quiz 562
Ceramic materials provide an alternative when choosing a tooth-colored restoration. Currently, posterior composite restorations can be used to achieve esthetic restorations; however, they have many disadvantages with regard to wear, polymerization shrinkage, discoloration, marginal leakage, and technique sensitivity. The use of CEREC CAD/CAM enables the dentist to place feldspathic porcelain (Vitablocs Mark II) and machinable glass ceramic (Dicor MGC) restorations in a single visit. When compared to composite materials, these materials closely approximate the physical properties of enamel in compressive and tensile strength and wear resistance. This study evaluated 50 CEREC CAD/CAM restorations after 4 years in service. Restorations ranged from Class I to 7/8s crown preparations. 相似文献
998.
999.
Portnof JE Israel HA Brause BD Behrman DA 《The Journal of the Michigan Dental Association》2007,89(4):46-8, 50-2
In 1997, the American Dental Association (ADA) and the American Academy of Orthopaedic Surgeons (AAOS) published an advisory statement regarding antibiotic prophylaxis for patients with total joint replacements undergoing dental treatment. The first periodic update of these guidelines was published in 2003. Nevertheless, confusion exists among dentists and physicians as to the clinical indications for premedication in this patient population. This article serves as an overview of current recommendations for use of chemoprophylaxis in the dental treatment of patients ith prosthetic joints. 相似文献
1000.
PURPOSE: Data are used to examine current and future conditions important to the private practice of prosthodontics. A concern is raised as to whether the future supply of prosthodontists is in sync with the dynamics of the US population and patient population. MATERIALS AND METHODS: Four trends are examined using data from various sources. The trends include: (1) growth in the number of private practicing prosthodontists, (2) projections of the future number of private practicing prosthodontists, (3) first year enrollment in dental schools, and (4) enrollments and graduates in residency programs. RESULTS: The number of private practicing prosthodontists has increased modestly over the past 21 years, growing 1.33% per year. The number of private practitioners is projected to reach 4,125 in 2025. A key variable in this projection is the growing number of elderly adults. While dental school enrollments have been increasing, concern is raised about the amount of exposure by students to an undergraduate curriculum in prosthodontics. There has been a general decline in enrollment in the nation's prosthodontics residency programs at the rate of -2.9% per year. An average of 181 program graduates are needed to achieve the 4125 projected number of private practitioners. CONCLUSION: Increasing demand for services from prosthodontists is supported by an increasing US population size and a growing population of elderly. Efforts to grow the number of private practicing prosthodontists will have to consider several concerns including residency program enrollments, undergraduate exposure to prosthodontics, and the overall economic returns expected from engaging in the private practice of prosthodontics. Choosing a career as a private practicing prosthodontist is a timely consideration and complimented by expected increases in demand for care and favorable financial returns to practice. 相似文献