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991.
Humphreys K Al Badri S Kinirons M Welbury RR Cole BO Bryan RA Campbell O Fung DE 《Pediatric dentistry》2003,25(5):475-478
PURPOSE: The objectives of the present study were to determine the prevalence of residual extrusion, pulpal necrosis, and resorption for extruded permanent teeth and to establish the effect of presentation and treatment factors. METHODS: Seventy-two traumatically extruded permanent incisors were studied at the Departments of Paediatric Dentistry in Belfast, Newcastle upon Tyne, and Glasgow. The mean age of the patients was 10.1 years (range=6 to 18 years). Clinical and radiographic outcomes were analyzed and related to presenting and treatment factors. RESULTS: The initial degree of extrusion was moderate for 46 teeth (64%), and the median delay prior to repositioning was 3 hours (range=1 to 168 hours). Pulp necrosis occurred in 31 teeth (43%), residual extrusion was present in 16 teeth (23%), and inflammatory resorption occurred in 11 teeth (15%). Residual extrusion was significantly associated with a delay in repositioning the tooth, pulpal necrosis was significantly more common in teeth with closed apices and in severely extruded teeth, and inflammatory resorption was more common after pulpal necrosis. CONCLUSIONS: Residual extrusion could be minimized by earlier presentation and repositioning. The risk of pulpal necrosis is greatest for severely extruded teeth and for those with closed apices. 相似文献
992.
993.
Milnes AR 《Journal (Canadian Dental Association)》2003,69(5):298-302
Providing comprehensive dental treatment for preschool children with early childhood caries (ECC) is probably the greatest challenge facing most dentists; many elect to hospitalize a child with ECC and provide treatment under general anesthesia. However, as waiting lists for hospital admission are long, ECC continues to progress and can cause pain or acute infection. Hospital treatment also results in substantial costs beyond those for dental treatment. This paper describes a cost-effective intravenous sedation program being used in a pediatric dental practice in Kelowna, British Columbia. The program offers an alternative to general anesthesia that allows qualified dentists to provide comprehensive dental treatment to children with ECC safely and efficiently in the private practice setting. 相似文献
994.
Bonding of self-etch and total-etch adhesives to carious dentin 总被引:7,自引:0,他引:7
Yoshiyama M Tay FR Doi J Nishitani Y Yamada T Itou K Carvalho RM Nakajima M Pashley DH 《Journal of dental research》2002,81(8):556-560
Carious dentin is partially demineralized and contains mineral crystals in the tubules. This may permit the deeper etching of intertubular dentin but prevent resin tag formation during bonding. We hypothesize that resin adhesives will produce lower bond strengths to caries-infected and caries-affected dentin compared with normal dentin. We tested this by measuring the microtensile bond strength of a total-etch adhesive and an experimental self-etching adhesive (ABF) to caries-infected, caries-affected, and sound dentin and by correlating those results with ultrastructural observations. The bond strengths of both adhesives to sound dentin were significantly (p < 0.05) higher than those to caries-affected dentin, which, in turn were significantly (p < 0.05) higher than those to caries-infected dentin. For both adhesives, hybrid layers in caries-affected dentin were thicker but more porous than those in sound dentin. The lower bond strengths may be due to the lower tensile strength of caries-affected dentin. Clinically, this may not be a problem, since such lesions are normally surrounded by normal dentin or enamel. 相似文献
995.
996.
For patients who lost one or more teeth, oral osseointegrating implants can offer a natural and solid solution. In order to rehabilitate (partially) edentulous patients with oral implants, a surgical intervention is inevitable. It is therefore of utmost importance that both esthetical and biomechanical demands are met in as few interventions and as little time as possible, which makes a thorough preoperative examination of the edentulous region mandatory. Radiographs of different kinds offer the possibility to evaluate bone volume and--to a lesser extent--quality of the area to be rehabilitated. It should however be kept in mind that radiography necessarily brings about a certain amount of possible detrimental radiation burden. Selection of the appropriate radiographic technique should therefore be based on a well thought-out balance between diagnostic value and risk level of the intervention on the one hand and radiation burden on the other. 相似文献
997.
Background. The necessity of nerve anastomosis in an attempt to regain cutaneous sensitivity following flap transfer has been the basis of many discussions. In our study, we investigated the degree of sensory recovery with emphasis on the different nerval qualities on the radial forearm and the latissimus dorsi flap. Collective. Sixty-two patients with 66 latissimus dorsi flaps and 19 patients with a radial forearm free flap were examined. Results. Except for five latissimus dorsi and two radial forearm flaps, all flaps investigated showed clinical signs of sensory recovery, whereby the degree and quality of cutaneous reinnervation varied. In comparison, neural reconstruction did not lead to any clinical improvement. Conclusion. Based on our clinical results, we consider nerve reconstruction during radial forearm and latissimus dorsi free flap transfer unnecessary. To what extent this can be said for other flaps requires further investigation. 相似文献
998.
J. I. Harris R. R. B. Russell M. A. Curtis J. Aduse‐Opoku J. J. Taylor 《Molecular oral microbiology》2002,17(4):224-230
Porphyromonas gingivalis produces virulence factors which can modify the molecular and cellular components of the host immune response. In the present work we investigated the role of specific virulence factors from P. gingivalis in the induction of apoptosis in Jurkat T cells. P. gingivalis culture supernatants mimicked the effect of butyric acid on T‐cell apoptosis and this effect was associated with an increase in histone H4 acetylation. A role for proteases was excluded in experiments which demonstrated that neither protease inhibitors nor use of P. gingivalis mutants defective in protease synthesis had any effect on the stimulation of T‐cell apoptosis in this system. 相似文献
999.
The emerging field of orofacial pain was considered by the American Dental Association for full status as a new dental specialty. While the recognition of orofacial pain as a specialty was denied, the American Academy of Orofacial Pain plans to continue its efforts. Many recent advances in the neuroscience of orofacial pain have led to treatments that provide significant relief for patients with chronic orofacial pain disorders. However, access to this care has been limited, leaving many patients to suffer. Dentists are generally supportive of the efforts to develop oral pain treatment into a specialty because the field will provide benefits for both dentists and their patients. A recent survey of 805 individuals who reported having a persistent pain disorder revealed that more than four out of 10 people have yet to find adequate relief, saying their pain is out of control--despite having the pain for more than five years and switching doctors at least once. "This survey suggests that there are millions of people living with severe uncontrolled pain," says Russell Portenoy, MD, president of the American Pain Society. "This is a great tragedy. Although not everyone can be helped, it is likely that most of these patients could benefit if provided with state-of-the-art therapies and improved access to pain specialists when needed." Development of the field of orofacial pain into a dental specialty has been moved primarily by the fact that historically, patients with complex chronic orofacial pain disorders have not been treated well by any discipline of healthcare. Recent studies of chronic orofacial pain patients have found that these patients have a higher number of previous clinicians and have endured many years with pain prior to seeing an orofacial pain dentist (see Figure 1). Complex pain patients and the clinicians who see them are often confused about who they should consult for relief of the pain. Treatment for those patients within the existing structure of dental or medical specialties has been inadequate, with millions of patients left suffering. Insurers are also confused with regard to reimbursement and may make decisions to exclude treatment for orofacial pain disorders under both dental and medical policies. However, dentistry has taken a leading role in healthcare to address the national problem of developing the field of orofacial pain into a dental specialty. A study of dentists and dental specialists has shown that there is a recognized need and broad support for developing this field into a specialty. 相似文献
1000.
Periodontal infection and preterm birth: results of a prospective study 总被引:22,自引:0,他引:22
Jeffcoat MK Geurs NC Reddy MS Cliver SP Goldenberg RL Hauth JC 《Journal of the American Dental Association (1939)》2001,132(7):875-880
BACKGROUND: Previous studies have suggested that chronic periodontal infection may be associated with preterm births. The authors conducted a prospective study to test for this association. METHODS: A total of 1,313 pregnant women were recruited from the Perinatal Emphasis Research Center at the University of Alabama at Birmingham. Complete periodontal, medical and behavioral assessments were made between 21 and 24 weeks gestation. After delivery, medical records were consulted to determine each infant's gestational age at birth. From these data, the authors calculated relationships between periodontal disease and preterm birth, while adjusting for smoking, parity (the state or fact of having born offspring), race and maternal age. Results were expressed as odds ratios and 95 percent confidence intervals, or CIs. RESULTS: Patients with severe or generalized periodontal disease had adjusted odds ratios (95 percent CI) of 4.45 (2.16-9.18) for preterm delivery (that is, before 37 weeks gestational age). The adjusted odds ratio increased with increasing prematurity to 5.28 (2.05-13.60) before 35 weeks' gestational age and to 7.07 (1.70-27.4) before 32 weeks' gestational age. CONCLUSIONS: The authors' data show an association between the presence of periodontitis at 21 to 24 weeks' gestation and subsequent preterm birth. Further studies are needed to determine whether periodontitis is the cause. CLINICAL IMPLICATIONS: While this large prospective study has shown a significant association between preterm birth and periodontitis at 21 to 24 weeks' gestation, neither it nor other studies to date were designed to determine whether treatment of periodontitis will reduce the risk of preterm birth. Pending an answer to this important question, it remains appropriate to advise expectant mothers about the importance of good oral health. 相似文献