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21.
Abstract – A histometric method was applied for evaluation of root resorption in 57 experimentally replanted teeth and 22 controls. Representative axiobuccolingual sections were selected for measurement of resorptions at a magnification of × 40. The frequency of root resorption in the control teeth was low. In replanted teeth marked resorptive activity elicited by the trauma appeared after 2 wk. The extent of active resorptions increased until the third postoperative week. On an average 14% of the root periphery was affected at this stage. After the sixth postoperative week progressive cement deposition took place in the resorption lacunae. Incidental ankylosis of the periodontal membrane also occurred from this observation time but there was no increase among the long-term groups. 相似文献
22.
23.
阻生智齿误入周围组织间隙的临床处理 总被引:1,自引:0,他引:1
目的 探讨下颌阻生智齿拔除术中意外进入周围组织间隙的原因及处理与预防措施。方法 对1984年5月至2002年10月共15例意外将牙齿或牙根推入软组织间隙的病例进行回顾性分析。结果 经过准确定位,15例软组织内的牙齿或牙根全部拔除。术后发生6例于槽症,1例多间隙感染。结论 术中判断误差和器械使用不当,是牙体进入软组织间隙的主要原因。一旦牙体进入间隙,准确的定位和合理的处理是减少并发症的关键。 相似文献
24.
目的:临床观察QuickWhite美白胶对氟斑牙患者的漂白治疗效果。方法:选取63例I ̄III级不同程度的氟斑牙患者,采用QuickWhite美白胶进行漂白治疗,分别于治疗前及治疗后用Vita比色板对牙齿比色并记录,评价治疗效果。评价标准:治疗后无改变为无效,变白2个色阶为有效,变白3个色阶以上为显效。结果:使用QuickWhite美白胶治疗后,I级患者显效率为95.6%,II级患者显效率为50%。结论:QuickWhite美白胶可为氟斑牙患者提供可靠的漂白治疗效果。 相似文献
25.
D. Locker 《Community dentistry and oral epidemiology》1997,25(3):199-203
Abstract Although numerous investigators have reported on self-perceived oral health status in adult and older adult populations, few have examined how these perceptions change over time. This paper uses data from a longitudinal oral health survey of community-dwelling Canadians aged 50 years and over to explore this issue. Data were collected at baseline and after 3 years. Change was assessed using a global transition judgement and change scores on four subjective oral health status indicators. These indicators addressed chewing capacity, oral and facial pain symptoms, other oral symptoms, and the psychosocial impact of oral disorders. Overall, 23.0% reported that their oral health had worsened over this period, 66.5% that it had remained the same and 10.5% that it had improved. Change scores on the four indicators showed a similar pattern and were significantly associated with these global judgements. Over the same period, substantial proportions lost one or more teeth, acquired new coronal or root DPS increments or experienced loss of periodontal attachment. An additional 17% complained of dry mouth. However, the only clinical indicator associated with changing perceptions of oral health was tooth loss. Of interest was the fact that rates of tooth loss were equally high among those who reported a worsening of oral health and those who reported an improvement. This suggests that the impact of tooth loss on health status may be positive or negative depending upon the condition of the teeth lost. 相似文献
26.
Denis O'Mullane PhD ; Helen P. Whelton PhD ; Pat Costelloe BDS David Clarke BDS ; Stephen McDermott MSc ; Jacinta McLoughlin MDS 《Journal of public health dentistry》1996,56(5):259-264
The visit of Dr. Trendley Dean to Dublin in the mid-1950s helped accelerate the decision to introduce water fluoridation as a public health measure in the prevention of caries in the Republic of Ireland. A challenge to the constitutional validity of the Health (Fluoridation of Water Supplies) Act 1960 failed and in 1964 the water supplies of Dublin city were fluoridated. Over the next seven to eight years all the major urban communities in the Republic of Ireland were fluoridated. Currently, 67 percent of the 3.5 million people in the country reside in fluoridated communities. Studies conducted over the last 20 years show that residents of fluoridated communities have better dental health than those in nonfluoridated communities—the mean dmft is lower in children and the number of natural teeth present in adults is higher. 相似文献
27.
Abstract – Dental injuries are common following facial trauma. This article presents a rare injury: the dislocation of a third molar into the maxillary sinus after complex mandibular and maxillary tuberosity fractures. The possible mechanism and clinical treatment are discussed. 相似文献
28.
Conor Armstrong Séamus S. Napier Robert C. Boyd Terry A. Gregg 《Journal of oral pathology & medicine》2004,33(4):246-248
Histological examination of the deciduous teeth in two cases of segmental odontomaxillary dysplasia (SOMD) showed fibrous enlargement of the pulps, an irregular pulp/dentine interface displaying many pseudoinclusions and pulp stones. There were tubular defects in the coronal dentine from pulp horn to cusp tip, an irregular tubular structure to the circumpulpal dentine of the apical half, a focally deficient odontoblast layer and widespread external resorption. Together with the clinical features of unilateral maxillary enlargement, upper alveolar expansion in the distal segment, increased spacing and delayed eruption of the deciduous molars and absence of premolar teeth, these histological appearances allow distinction of this condition from fibrous dysplasia (FD), segmental hemifacial hypertrophy (SHH) and regional odontodysplasia (ROD). 相似文献
29.
饮水锶对大鼠骨骼生长发育影响的实验研究 总被引:1,自引:0,他引:1
研究了高锶饮水对大鼠骨骼生长发育的影响。结果表明,饮水中锶浓度为5~500mg/L达12周可引起Wistar大鼠血清、尿、股骨、颌骨和牙齿中锶含量增高,呈明显的剂量-反应关系。同时,锶还可使骨骼钙含量降低,牙齿钙含量和骨骼的骨密度增高,以及除第12周雌性大鼠外血清钙水平下降。尚未发现锶对动物体重、体长、血清AKP活性、尿钙水平以及股骨弯曲断裂载荷的影响。然而,锶对动物骨骼生长发育影响性别之间存在差异,如在第12周染锶组雄性大鼠血清钙含量降低,而雌性大鼠升高;在第4周和第8周时,仅雄性大鼠尿Hop/Cr比值增高,而雌性大鼠维持于正常水平;Sr2+还使雄性大鼠颌骨骨密度增加,而雌性大鼠股骨骨密度增加。上述改变提示可能是动物性别之间在内分泌调节和代谢过程上不同的结果。 相似文献
30.
目的 :观察高血压患者在监护拔牙过程中血压、心率、心电图变化及手术应激反应的年龄差异 ,探讨安全科学的监护方法。方法 :对 739例高血压患者监护拔牙的临床资料进行回顾性分析。观察高血压患者和不同年龄组高血压患者麻醉前、中、后 ,拔牙中、拔牙后 ,血压、心率变化。结果 :高血压组血压、心率比对照组显著增高、加快 (P <0 .0 1) ;80岁以上年龄组收缩压显著升高 (P <0 .0 1) ,4 9岁以下年龄组收缩压显著降低 (P <0 .0 5 ,P <0 .0 1)。结论 :各种高血压患者特别是高龄高血压患者 ,在分时安全管理下可以接受无痛拔牙。 相似文献