下颌第二磨牙"C"形融合根及其根管形态的观察

目的　观察具有“C”形融合根的离体下颌第二磨牙牙根外形及根管形态。方法　通过牙根水平片切及透明标本的制作 ,观察 4 0颗下颌第二磨牙牙根的形态特点 ,并测量其长度。结果　牙根均在颊侧融合 ,牙根长度较正常牙长且有显著性差异 (P <0 .0 5 )。根管形态变异较多 ,仅 4 0 %呈现根颈到根尖的“C”形 ,3 0 %为“分号”形 ,10 %为“分离”形 ,2 0 %的牙根内各横断面形态可有不同。结论　下颌第二磨牙“C”形融合根的变异较多 ,不利于根管的彻底清理和充填     

牙冠延长术后冠修复的有限元模型建立

目的探讨下颌第二双尖牙不同程度冠根折后行牙冠延长术并冠修复的三维有限元模型建立方法。方法通过螺旋CT扫描获得原始数据．将获得的二位图像数据输入Mimics软件建立三维图像．将三维图像数据导入ANSYS软件．运用ANSYS软件对模型进行修改并划分网格形成三维有限元模型。结果建立6个下颌第二双尖牙不同程度冠根折行牙冠延长术并桩冠修复的三维有限元模型：M0、M1、M2、M3、M4和M5。结论用此方法建模方便快捷，所建立的模型具有良好的几何相似性和生物相似性。     

Correlation of plasma osteopontin and osteocalcin with lower renal function in dental patients with carotid artery calcification and tooth loss

ObjectivesTo investigate plasma osteopontin (OPN) and osteocalcin (OCN) levels in dental patients with carotid artery calcification (CAC) and determine the correlations between these proteins and renal function and tooth loss.MethodsThe health parameters and number of teeth of 99 participants were recorded. Panoramic radiographs were taken for CAC evaluation, and OPN and OCN levels were measured.ResultsNone of the participants had overt kidney disease, and 14 (14.14%) had CAC. The age, sex, and health profiles of patients with CAC were not different from those without CAC. The OPN and OCN levels in participants with CAC were higher than in those without (p = 0.026 and p = 0.025, respectively). The OPN levels were correlated with the estimated glomerular filtration rate (eGFR) (p = 0.021) and tooth loss (p = 0.027). The OCN levels were correlated with the eGFR (p = 0.002), tooth loss (p = 0.023), blood urea nitrogen (p = 0.040), and creatinine levels (p = 0.031). The median tooth loss in individuals with an eGFR <60 mL/min/1.73 m² was higher than that of individuals with an eGFR ≥60 mL/min/1.73 m² (p = 0.033). In individuals with CAC, tooth loss correlated more strongly with the eGFR, and the correlation between OPN and OCN levels was more apparent.ConclusionDental patients with CAC and increased tooth loss have a greater tendency for decreased renal function, which may be associated with OPN and OCN; thus, these patients should be referred for investigation.     

Periodontal disease,undiagnosed diabetes,and body mass index: Implications for diabetes screening by dentists

BackgroundPeriodontal disease and diabetes are widespread comorbid conditions that are detrimental to oral and overall health. Dentists' performing chairside screenings for undiagnosed diabetes mellitus (UDM) can be beneficial to both patients and providers. The authors determined UDM rates in a population-based study and whether UDM and periodontal disease were independently associated.MethodsData from 7,343 participants in the Atherosclerosis Risk in Communities study visit 4 were used to determine rates of UDM by periodontal status, edentulism, and body mass index. The authors used a χ² test or analysis of variance, along with a 2-stage logistic regression model, to determine relationships with UDM. UDM was defined as no self-reported diabetes and blood glucose levels (fasting glucose ≥ 126 milligrams/deciliter or nonfasting glucose > 200 mg/dL). Periodontal disease was defined using the Periodontal Profile Classes system adapted to stages and the Centers for Disease Control and Prevention and American Academy of Periodontology index.ResultsUDM rates overall were 5.6%. The highest rates occurred in patients who were obese and edentulous (12.6%) and obese and had severe periodontal disease (12.2%). Significant associations were found for UDM and severe periodontal disease (Periodontal Profile Classes system stage IV) (odds ratio, 1.78; 95% confidence interval, 1.10 to 2.88). Edentulism was significantly associated with UDM in the Periodontal Profile Classes system model (odds ratio, 1.87; 95% confidence interval, 1.27 to 2.75) and Centers for Disease Control and Prevention and American Academy of Periodontology index (odds ratio, 1.70; 95% confidence interval, 1.08 to 2.67). Hyperglycemia was found in participants of all body mass index categories.ConclusionsUDM is significantly associated with obesity, edentulism, and periodontitis. These characteristics could help dentists identify patients at higher risk of developing DM. Patients without these characteristics still have UDM, so dentists performing chairside diabetes screening for all patients would yield additional benefit.Practical ImplicationsDental offices are a major point of contact within the US health care system. Diabetes screening in this setting can provide important health information with direct relevance to patient care.     

牙齿病理性磨损充填治疗的临床效果研究

目的观察尚未出现牙髓症状的牙齿病理性磨损充填治疗的临床效果。方法选择牙列完整、后牙骀面有病理性磨损且具有充填空间的患者10例，患牙48颗，均无牙髓症状。使用后牙树脂充填后，比较治疗前、治疗后3个月和1年时，患者主观感觉和咀嚼功能（咬合力、咀嚼效率和咬肌肌电活动）的变化，观察树脂充填的临床效果（美国公共健康部评价系统）。结果患牙经充填治疗后患者临床症状消失，咬合力增加（P〈0．05），咀嚼效率明显提高（P〈0．01），治疗前后下颌息止位、大力咬合时、咀嚼运动时，颞肌前束和咬肌的活动强度、活动对称性及用力方式差异均无统计学意义（P〉0．05）；治疗后3个月和1年时复查，48颗后牙树脂充填体各项指标A级率为100％。结论对后牙骀面尚未出现牙髓症状的病理性磨损用树脂进行充填是一种有效的治疗方法，可以解除患者的临床症状，减缓磨损的发展，增加咀嚼效率及患牙咬合力。     

牙体预备形态对烤瓷贴面复合体抗折强度及断裂模式的影响

目的比较三种牙体预备方法对烤瓷贴面复合体（PVCs）抗折强度及断裂模式的影响。方法分别对离体上颌中切牙进行3种形态（I型、L型、U型）牙体预备，制作长石质烤瓷贴面，树脂黏接剂黏接．用MTS力学实验机测试各牙的断裂载荷值，记录瓷贴面的断裂频数，数据作统计学分析。结果I、L、U三型牙体预备的PVCs与天然牙对照组的断裂载荷值分别为278．61±73．86N（n=9）．295．17±71．76N（n=9），303．42±96．87N（n=8），332．29±60．06N（n=10），经统计学分析四组间断裂载荷值及瓷贴面的断裂模式差别无统计学意义（P〉0．05），3组实验组与对照组的牙体断裂模式差异有统计学意义（P〈0．05）。结论在正中[牙合]瓷贴面间接受力的条件下，采用3种牙体预备设计的PVCs均具有良好的的抗折性能．但烤瓷贴面修复改变了牙体组织在加载条件下的力学特性。     

Periodontal regeneration of transplanted rat molars after cryopreservation

The effects of cryopreservation on periodontal regeneration of transplanted rat molars were investigated histologically and histochemically in rats. Bilateral first and second maxillary molars of 4-week-old Wistar rats were gently extracted and transplanted into the abdominal subcutaneous connective tissue immediately or after cryopreservation in liquid nitrogen overnight. Donor teeth were slowly frozen by a rate-controlling freezer (program freezer) using 5% dimethylsulfoxide (DMSO) and 6% hydroxyethyl starch (HES) as cryoprotectants. One-four weeks after transplantation, they were carefully excised with the surrounding tissues. Regeneration of acellular cementum, periodontal ligament, and alveolar bone were observed 2 weeks after immediate transplantation. The pulp was repaired by the ingrowth of granulation tissue from the root apex followed by the formation of calcified tissue. The regenerated periodontal ligament was positive for alkaline phosphatase (ALP). Small or mononuclear tartrate resistant acid phosphatase (TRAP) positive cells were scattered on the newly formed alveolar bone and on the hard tissue in the pulp, but there was no external or internal progressive root resorption at 4 weeks. Cryopreserved teeth had acellular cementum with a rough surface at 1 week, but with the increase of cementoblasts and the appearance of periodontal ligament and alveolar bone, the surface became smooth at 3 weeks. Epithelial rests of Malassez (ERM) also revived. After regeneration of the periodontal tissues at 4 weeks, there was no evidence of root resorption. Although the process proceeded slowly, the cryopreserved teeth showed the periodontal regeneration substantially similar to that of the immediately transplanted teeth without progressive root resorption, indicating that they could be applicable for clinical use.     

微创拔牙即刻种植的牙龈美学效果观察

目的探讨微创拔牙即刻种植技术的临床特点及修复后的牙龈美学效果。方法21例上前牙单个缺失病例，行不翻瓣微创拔牙同期23颗种植体即刻植入，并且同期安装愈合基台直接暴露于口腔，即非埋入式种植术式，种植体愈合6个月后进行永久修复。种植永久修复后观察时间平均27．6个月（13～51个月）。根据Jemt牙龈乳头指数（papilla index score，PIS）观察种植体永久修复12个月后的近远中牙龈乳头状况，根据Flirhauser的改良红色美学指数观察种植体永久修复1年后与相邻天然牙唇侧龈缘位置的协调性；唇侧软组织与相邻天然牙唇侧牙龈色泽协调性。结果23颗种植体均获得良好的骨结合；种植修复体近远中PIS均为Ⅱ级以上。种植修复体与相邻天然牙唇侧牙龈缘水平位置协调性一致的15颗，8颗不协调；唇侧软组织色泽与相邻天然牙协调一致的18个牙位，5个牙位有轻度差异。结论微创拔牙即刻种植术是一项要求较高的技术，多因素影响软组织美学效果，严格掌控适应证，才能获得理想修复效果。     

Efficacy of Commiphora myrrh mouthwash on early wound healing after tooth extraction: A randomized controlled trial

BackgroundThe early period after tooth extraction is a critical period for wound healing. Wound healing after tooth extraction is considered secondary intention healing. It passes through several stages in the following order: hemostasis, inflammatory phase, proliferative phase, and finally the remodeling phase.Wounds usually heal normally unless there is interference by local or systemic factors. In certain circumstances, early wound healing can be enhanced by several interventions such as antibiotics, mouthwashes, or topical medications. Myrrh has been used as a topical medication for promoting wound healing after tooth extraction. The purpose of this study was to assess the wound healing effect of myrrh mouthwash during the early post-extraction period.MethodsWe enrolled 40 healthy adult patients in this study (20: study group and 20: control group). All the activities performed for each group were double-blinded. All the participants underwent dental extraction under local anesthesia using standard protocol. Next, the study group used Commiphora molmol (myrrh) extract as a mouthwash while the control group used normal saline mouthwash. The participants used the mouthwashes twice a day for 7 days starting from the first post-extraction day. Clinical examination data were recorded and analyzed using the Mann Whitney Wilcoxon test.ResultsThere was a statistically significant between-group difference in postoperative surgical-site edema, tenderness, and socket size, with the test group showing greater improvements.ConclusionsMyrrh mouthwash has an enhancement effect on wound healing during the early period after tooth extraction.     

AVULSION OF PERMANENT TEETH: ANALYSIS OF THE EFFICACY OF AN INFORMATIVE CAMPAIGN FOR PROFESSIONALS FROM ELEMENTARY SCHOOLS

Tooth avulsion is a very common event in children and emergency care procedures are crucial for case prognosis. As anyone at the moment of accident can provide first-aid measures, knowledge of school professionals dealing with children is of paramount importance. An informative campaign about dental trauma was performed in urban schools in the city of Adamantina, São Paulo state, Brazil, in an attempt to educate school professionals about emergency procedures in cases of tooth avulsion. A questionnaire arguing on personal information, tooth avulsion knowledge and personal impressions of the campaign was handed out for evaluation of the informative campaign. Eighty school professionals participated in the survey. Most participants were females (93.75%) aged 41-60 years old (53.75%) with a college degree (77.5%). Time at work ranged from 1-5 years (22.5%). The efficacy of the campaign was considered positive, as 100% of the interviewees replied to the importance of emergency procedures in case of tooth avulsion. In addition, 81.25% of the respondents answered that they would store the avulsed tooth in some storage medium, of which milk was the most frequently mentioned (84.61%). The participants considered the campaign as satisfactory and a region-wide campaign will be accomplished at other schools.