Rate and predictability of pulp revascularization in therapeutically reimplanted permanent incisors

Abstract The aim of the present investigation was to study the frequency of pulp revascularization in therapeutically reimplanted incisors as well; is its relationship with the following factors: width of apical foramen, duration of extra-alveolar lime, storage conditions and postoperative administration of antibiotics. Out of 72 immature teeth (width of apical foramen 1.1–5.0 mm) the pulp was revascularized in 13 (18%), while in 88 mature teeth (width of apical foramen 1.0 mm or less) no revascularization occurred. Among parameters tested statistically in immature teeth, a significantly increased frequency of revascularization (p < 0.05) was only found in teeth reimplanted within 45 minutes after avulsion, when compared with teeth reimplanted after a longer extra-alveolar time, and in mandibular incisors when compared with maxillary incisors (p < 0.01). All teeth in which revascularization did not occur exhibited a periapical radiolucency and/or external inflammatory root resorption.     

Comparison of computer-assisted learning with tutorial teaching in a group of first-year dental students

Two identical groups of first-year dental students were instructed in the pathology of dental caries and periodontitis using computer-assisted learning (CAL) or tutorial teaching (TT). A cross-over arrangement, in which the first group was taught about dental caries by CAL and periodontitis by TT and the second group in the reverse order, allowed comparison of the two methods. The comparison included a knowledge test and completion of a questionnaire. CAL and TT were equally effective as far as acquisition of knowledge was concerned. Students felt pressurized with CAL and had problems with note-taking. They liked a teacher to be present. Nevertheless, CAL was an acceptable method of instruction and was more economical, in terms of staff involvement, than TT.     

Effects of cooling and heating of the tooth on pulpal blood flow in man

Abstract Laser Doppler flowmetry (LDF) was used to study the changes in pulpal blood flow (PBF) evoked by application of cold or heat to the palatinal surfaces of teeth 11 or 21 in nine young subjects. Switching from a thermode temperature of 33° to 5° G on average induced a slow decrease of PBF to about 80% of control, and also warming to 39°C evoked a small reduction in most subjects. Inter individual differences were large, however, and both cooling and warming sometimes triggered a rise in PBF. In contrast, skin blood flow, as recorded with LDF in the forearm, invariably rose during warming and fell during local cooling. The results suggested a more complex interaction between local and nervously mediated effects of moderate changes in temperature in the tooth pulp than skin, and that the previous held view of cold and heat decreasing and increasing PBF, respectively, is wrong.     

Eligible Veterans'' Choice Between VA-covered and Non-VA-covered Dental Care

Veterans who were eligible for dental care in Department of Veterans Affairs (VA) facilities at no monetary cost responded to a mailed questionnaire. Seventy-one percent were aware that they were actually eligible for VA dental care. However, only 48 percent reported the VA as their only or primary source of dental care. Eligibility status, perceived quality of VA dental care, use of VA medical care, perception that one's income meets expenses, and perceived need for dental care were significant correlates of using the VA as one's current source of dental care. Level of formal education, perception that one's income meets expenses, transportation pattern, geographic distance from a VA facility, and eligibility status were significant correlates of using the VA as one's current medical care source. Research on VA utilization offers the opportunity to study issues of access to, and use of, a large public health care system whose patients largely receive care at no monetary cost. Veterans' use of VA dental and medical care is apparently influenced by a wide variety of factors, ranging from barriers to access to non-VA systems, to characteristics of the VA delivery system itself, to need for treatment.     

Long-term result of guided nerve regeneration with an inert microporous polytetrafluoroethylene conduit

Thedevelopmentinmicrosurgicaltechniqueshasgreatlyimprovednervefunctionalrecovery .However ,owingtotheinabilitytocoaptateandsuturethousandsofnervefiberstotheirfunctionallysimilarnervefibersandinaccuratesutureofthenervestumps ,regeneratednervefiberspartiallylosethechancetoselectivelyregrowintotheirtargetendoneurialtubes,1 4whichresultsinaninevitablemismatchofmotorandsensorynervefibers .Thus,thecontact guidance basedmicrosurgicalnerverepairhasfailedtoachieveconsistentsatisfactoryfunctionalrecover…     

重度磨耗患者髁道运动学初步评价

评价重度磨耗患者后方髁道运动学特征 ,探讨髁状突运动与牙合重建的关系。方法 :运用Pantronic髁状突运动描记系统和D5ADenar全调节式咬合架 ,对 15例中老年重度磨耗患者后方髁道决定因素对牙合运动的影响 ,以及对 5例已完成咬合重建的重度磨耗患者髁道运动学特征进行初步评价。结果 :15例重度磨耗患者平均髁间距离为 ( 60 .72± 4.40 )mm ,迅即侧移量 (ISS) 1.3 5mm (右 )和 1.2 4mm (左 ) ,渐进侧移量 (PSS)为14 .65°(右 )与 17.11°(左 ) ,前伸髁导斜度 (PRO)为 2 3 .45°(右 )与 2 6.85°(左 ) ,非工作侧髁道值 (ORB)为 2 6.5 0° ,前伸髁导斜度与非工作侧髁道之间极相关 ,存在较小的Fisher角。结论 :咬合重建主要影响侧移量和Pantronic重复运动指数 (PRI)的大小 ,反映出下颌侧方边缘运动限制所恢复的程度。但牙合重建对非工作侧髁道没有明显的影响 ,运动道的变化并不能预测治疗的效果。     

胃恶性上皮核仁组成区相关蛋白的研究

用嗜银染色技术对34例良性胃溃疡、40例胃粘膜异型增生、46例胃腺癌组织石蜡切片中的核仁组成相关蛋白(AgNOR)进行研究,25例正常胃粘膜组织作对照。发现对照组、良性溃疡组,异型增生组和腺癌组的细胞核AgNOR平均计数差异有显著性(P<0.01)。恶性细胞中AgNOR的体积、形状及在细胞核内的位置也不相同。作者认为此法有助于区别胃的良性和恶性病变。     

Comparative study of oral conditions in schoolchildren of Strasbourg, France, 1974–85

A representative sample of 1650 children randomly selected in the 6-15-yr-old schoolchild population of Strasbourg was examined by well-calibrated examiners. The prevalence of caries was determined with the DMFT, DMFS and dft indices using bitewing radiographs. Plaque, calculus and gingival indices were also determined. The results obtained were compared with the initial study of 1974 performed in Strasbourg using the same epidemiologic methods. Whereas no important variations were observed in caries prevalence of primary teeth, a significant reduction of caries activity was observed in DMFT and DMFS indices in all age groups. There was a reduction of these two indices of respectively 32% and 33% in the 12-yr-old children. The reduction was the most significant on approximal surface lesions. A statistically significant decrease of the calculus and gingival indices was also observed between 1974 and 1984. A less significant decrease was observed for the plaque index.