栀子标准汤剂的质量评价方法考察

目的:建立栀子标准汤剂的质量评价方法,为所有源于栀子水提液的制剂的质量标准制定提供参考。方法:制备15批栀子标准汤剂,测定其出膏率、指标成分转移率和pH;建立栀子标准汤剂的UPLC指纹图谱并对主要色谱峰进行质谱鉴定,离子化模式为正、负离子,离子源温度150℃,脱溶剂气体为高纯度氮气,温度550℃,流速800 L·h~(-1),毛细管电压1.0 kV,锥孔电压30 V,扫描范围m/z 50~1 200。结果:栀子标准汤剂的平均出膏率28.4%,栀子苷转移率77.7%,p H均为4。所有样品的指纹图谱相似度均0.99,栀子标准汤剂的主要成分为栀子苷。结论:建立的栀子标准汤剂的质量评价方法稳定可行、重复性好,该评价方法灵敏、准确,为所有源于栀子水煎剂的制剂的质量控制提供参考。     

红花标准汤剂的质量评价

目的:建立红花标准汤剂的质量控制方法。方法:收集有代表性的14批红花,制备红花标准汤剂,计算出膏率、指标成分转移率和溶液pH等参数,评价工艺的稳定性;建立指标成分含量测定和指纹图谱方法,采用UPLC-Q-TOF/MS对主要色谱峰进行结构确认,明确红花标准汤剂中的主要化学成分。结果:标准汤剂出膏率32.6%,羟基红花黄色素A的转移率61.2%,pH 4.1;标准汤剂中羟基红花黄色素A平均质量浓度3.6 g·L~(-1),指纹图谱相似度均0.9,标准汤剂的主要成分为黄酮类。结论:建立了系统评价红花标准汤剂的质量评价方法,为所有源于红花水煎液的制剂的质量标准制定提供参考,所得红花标准汤剂的指标成分转移率高、质量均一性良好。     

Traumatic injuries to the primary dentition and effects on the permanent successors – a clinical follow-up study

Abstract –  This study investigated problems in the permanent dentition that, according to history and records, were attributable to dental alveolar injuries of the primary dentition. 106 children have been involved in the study, who had experienced primary anterior tooth trauma affecting a total of 200 teeth. Thirty-nine patients (81 teeth) were available for follow-up examinations. In 25% of the cases followed up, damage was found on the successors in the secondary dentition (16 children/20 teeth). In half of the cases, a comparatively mild form of lesion like enamel discoloration was observed. This was the result of an injury during the tooth maturation process causing enamel hypoplasia. Clinically more relevant were the dental deformities: cessation of root formation or retention caused by ankylosis, which made up the remaining 50% of cases. This was confirmed by clinical long-term observation. The different effects on the permanent teeth can only be detected by radiography after an interval of several months or may even be clinically assessed only after the eruption of the clinical crown.     

盐酸米诺环素软膏治疗干槽症的临床观察

目的:比较盐酸米诺环素与碘仿纱条在治疗干槽症中的疗效。方法:对42例确诊为干槽症的患者经过常规清创后,分别采用牙槽窝注射盐酸米诺环素(21例)或者填塞碘仿纱条(21例)的方法治疗,借以控制或缓解临床症状,随访比较其疗效。结果:两种治疗方法的总有效率没有明显差异,但是盐酸米诺环素组的疗效评价为良好的比例明显高于碘仿纱条组(P<0.05)。结论:盐酸米诺环素牙用软膏辅助治疗干槽症是一种行之有效的方法。     

Oxygen reduction mechanism on corroded zinc

The mechanism of oxygen reduction on the as-polished and corroded zinc specimens has been studied using a rotating ring disc electrode (RRDE) system. On the as-polished surface, oxygen was reduced into two distinct steps. In the first step, about 44% of O₂ was reduced to H₂O₂ in a 2-electron reaction with the rest being reduced to OH^? in a 4-electron reaction. On the other hand, in the second step, with the increase of overpotential O₂ was almost exclusively reduced to OH^? in a 4-electron reaction. The first step reduction occurred on an air-formed oxide-covered surface at more positive potential than ?1.2 V vs. Ag/AgCl and the second step reduction (E < ?1.2 V) took place on a semi-uniformly active surface. On the corroded surface, the second step was not distinctly observed on the polarization curve, because reduction of the zinc corrosion products simultaneously took place around ?1.2 V. The O₂ reduction in the first step was inhibited by deposition of the corrosion products, though the ratio of amount of O₂ reduced to OH^? in a 4-electron reaction was larger than that on the as-polished surface. The mechanism of oxygen reduction is discussed on the basis of results obtained from the RRDE experiment.     

Shear bond strength of one-step self-etch adhesives with different co-solvent ingredients to dry or moist dentin

Objective

To evaluate the shear bond strength of one-step self-etch adhesives with different co-solvent ingredients to dry or moist dentin.

Materials and methods

A total of 60 extracted teeth were used in this study, and were divided according to the adhesive systems and dentin conditions into 6 groups of 10 teeth each [Xeno III – dry dentin, Xeno III – moist dentin, Adper Prompot L-Pop – dry dentin, Adper Prompot L-Pop – moist dentin, iBond – dry dentin, and iBond – moist dentin]. Resin composite cylinder was built up on each specimen, and then thermocycled. A shear load was applied to the specimens using universal testing (Instron machine) at a cross-head speed of 0.5 mm/min until failure occurred. Data were statistically analyzed by one-way ANOVA and Bonferroni multiple comparison test at 95% confidence level.

Results and conclusion

Based on the findings of this study: The highest mean shear bond strength to dry dentin was seen when Xeno III containing ethanol co-solvent ingredient was used. The highest mean shear bond strength to moist dentin was seen when iBond which contains acetone co-solvent ingredient was used. In the absence of a co-solvent ingredient in self-etch adhesive (Adper Prompot L-Pop), the mean shear bond strengths to dry and moist dentin were low with no significant difference between them.     

Traumatic intrusion of permanent teeth. Part 3. A clinical study of the effect of treatment variables such as treatment delay,method of repositioning,type of splint,length of splinting and antibiotics on 140 teeth

Abstract – A prospective study of 140 intruded permanent teeth was examined for the following healing complications: pulp necrosis (PN), root resorption (RR; surface, inflammatory and replacement resorption), and defects in marginal periodontal bone healing (MA). The occurrence of these healing complications was related to various treatment factors such as treatment delay, method of repositioning (i.e. expecting re‐eruption, orthodontic reposition and surgical reposition), type of splint (rigid, semirigid and flexible), length of splinting (days) and the use of antibiotics. Treatment delay, i.e. before and after 24 h, had no effect upon healing. Active repositioning in individuals with incomplete root formation (surgical or orthodontic) had a negative effect upon the three healing parameters compared with spontaneous eruption. In teeth with complete root formation and an age of 12–17 no repositioning was still the best treatment in regard to MA. In individuals older than 17 years of age, cases were not anticipated to spontaneously erupt and in these cases, the general choice of treatment was either active orthodontic or surgical repositioning. The former procedure appeared in this treatment scenario to slightly reduce the risk of MA complications. However, this treatment procedure was also found to be more time demanding (an average of 22 consultations for orthodontic repositioning compared with 17 consultations for surgical repositioning). If a surgical repositioning was performed, the type of splint (i.e. flexible, semirigid or rigid) appeared to have no significant effect on the type of healing. The same applied to the length of splinting time (shorter or longer than 6 weeks). No effect of dentin covering procedures for associated crown fractures (enamel–dentin fractures) could be demonstrated. Likewise, antibiotics had no apparent effect upon healing. In conclusion, in patients with intruded teeth with incomplete root formation, spontaneous eruption should be expected. In patients with completed root formation and with an age of 12–17 spontaneous eruption can still occur, but must be monitored very carefully. In older patients (i.e. >17 years) with completed root formation, either surgical or orthodontic extrusion should be attempted. The latter procedure appeared to lead to a slight reduction (not significant) in the risk of MA complications. The extent and direction of the intrusion may however favour surgical repositioning.     

A Rationale For Not Connecting Implants to Natural Teeth

When restoring partially edentulous arches with implants, there are some practitioners who believe it is occasionally beneficial to connect implants to natural teeth. This connection is performed to gain shared support from the natural tooth and implant, prevent rotation of the restoration, or sometimes merely to retain the natural tooth. A discussion and review of the literature concerning this connection is presented, and a patient treatment is shown to illustrate potential complications.     

Developmental anomaly of permanent teeth related to traumatic injury

Abstract A case is presented where a 4-year-old girl was injured in an automobile accident. The dental injury, intrusive luxation of the maxillary deciduous incisors, seemed unimportant at the time, since the child was in critical condition. The situation was first evaluated 5 years later, when the child was referred for treatment of an apical periodontitis originating from the right central incisor. The present case reflects several important aspects that were overlooked at the time of injury: the potential of intruded luxated deciduous teeth to cause developmental anomalies to the permanent dentition; the necessity of a longer follow-up period to detect such anomalies; and the need to develop effective treatment methods.     

微型种植体支抗和XIVE种植体在牙列缺损修复中的临床应用

目的：探讨用微型种植体作为正畸支抗压低伸长磨牙,同时用XIVE种植体修复对（牙合）缺失牙的可行性.方法：选择7例下颌第一磨牙缺失,对颌牙伸长＞2.5mm种植修复的患者.在对颌伸长的第一磨牙的近中腭侧和远中颊侧各植入1枚微型种植体.用橡皮链挂在颊、腭侧的种植体上,以压低伸长的对颌牙齿,定期更换并进行临床检查.同时缺牙区植入XIVE种植体,常规种植治疗.结果：7例患者中,1枚微型种植钉松动脱落,余6例患者伸长牙平均压低3mm,平均压低时间为5个月,经种植修复后均获得满意的临床效果.结论：针对下颌第一磨牙缺失对颌牙伸长较多的病例,微型种植体支抗和种植体的联合应用,能达到良好的修复效果.