Search

Copyright of Imaging Science & Photochemistry is the property of Imaging Science & Photochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective · To observe the effects of custom made fiber posts on the fracture resistance of young permanent teeth treated with calcium hydroxide for different time. Methods · Forty-five extracted human young permanent teeth (premolar) were selected and randomly assigned to 9 groups. One group was the control group and the rest 8 groups were treated with conventional root canal preparation. Of these 8 groups, 4 groups (FI, FIII, FIV, FIX) were restored by custom made fiber posts after being treated with calcium hydroxide for 1, 3, 6, and 9 months respectively, and other 4 groups (CI, CIII, CIV, CIX) were not restored by custom made fiber posts. All samples underwent fracture strength tests and their fracture modes were analyzed for the possibility of second repair. Results · The fracture load was decreased with the treatment time after being treated with calcium hydroxide for 1 month (P<0.01). The fracture loads in groups restored by custom made fiber posts were increased after being treated with calcium hydroxide for 6 and 9 months (P<0.05, P<0.01). After being treated with calcium hydroxide for 1 month, groups restored by custom made fiber posts were likely to have fracture modes that facilitate the second repair as compared with groups not restored by custom made fiber posts (P<0.05). Conclusion · The restoration by custom made fiber posts can increase the fracture resistance of young permanent teeth treated with calcium hydroxide for medium and long term ( ≥ 1 month). [ABSTRACT FROM AUTHOR]

Objective The aim of the present study is to investigate the prognosis and influencing factors of crownfractured young permanent teeth with pulp exposure. Methods Case records of crown-fractured young permanent teeth with pulp exposure in the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology during 1991 to 2008 with more than 2 years follow-up were collected. These patients were treated with pulpotomy at the first visit at our hospital no matter whether these teeth were treated or untreated with direct pulp capping. The age of patients, interval between trauma and treatment, root development, mobility and tenderness to percussion were recorded. The prognosis was analyzed and Logistic: regression was used to analyze the influencing factors. Results Totally 118 cases satisfied the inclusion criteria, including 136 crown-fractured teeth with pulp exposure. The patients of (8.8+1.2) years old were periodically monitored for (46.1±22.0) months. The success rate of pulpotomy after pulp exposure was 85.3%. Pulp necrosis occurred in 20 teeth (25.0±19.0) months after trauma. The extent of tenderness to percussion showed significant correlation with pulp necrosis, while the age of the patients, interval between injury and treatment, and mobility of the teeth were not related to pulp necrosis. Conclusion The success rate of pulpotomy after pulp exposure is good. Tenderness to percussion is an important signal of pulp necrosis. There are no evidence about the relationship between the patient's age, interval between injury and treatment, mobility of the pulp-exposed teeth and the pulp prognosis. [ABSTRACT FROM AUTHOR]

PURPOSE: To compare the young permanent teeth enamel demineralization after immersion in different kinds of soft drinks; to compare the degree of enamel demineralization caused by the different immersion time and frequency of beverages. METHODS: The change of young permanent teeth enamel surface microhardness was measured by a leitzs microhardness tester. The change of calcium and phosphate in the different drinks after immersion of the enamel was analyzed by Roche Biochemical analyzer. Two-way ANOVA in SPSS 15.0 software package was used for statistical analysis. RESULTS : The dissolution of calcium and phosphate in young permanent teeth enamel was caused by all kinds of soft drinks the surface microhardness of enamel was decreased by these drinks. There were great significant differences in the demineralization abilities among different beverages (P<0.05).The enamel demineralization was increased when prolonging the immersion time and frequency. CONCLUSIONS: The enamel demineralization can be caused by orange juice and carbonic acid drinks. The enamel remineralization can be increased by tea drink, which is an ideal healthy beverage. Supported by Excellent Middle-aged Science Foundation of School of Medicine, Shanghai Jiao Tong University (Grant No.040407). [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical effect of root canal obturation therapy using cold flowable gutta-percha on young permanent teeth after apexification., Methods: Ninety cases of young permanent teeth with pulp necrosis or periapical periodontitis treated by apexification were randomly divided into two groups. The cases in each group were divided into single root canal and multiple root canal according to the number of the root canal, and divided into classifications Ⅰ, and Ⅱ/Ⅲ/Ⅳ according to Frank's classification of root development after apexification. Cold flowable gutta-percha and warm gutta-percha obturation techniques were used for root canal obturation of the two groups. The operation time was recorded, and the patients' therapy pain degree was evaluated by visual analog scale (VAS) immediately after operation. Periapical X-ray was performed after operation to evaluate the effect of the root canal filling. The total length of the root was divided into equal three parts on the X-ray film, and three-dimensional tightness of the apical, middle, and coronal region of the root canals were statistically analyzed respectively. Clinical examinations and X-ray examination were performed 6 and 12 months after the operation to evaluate the treatment success rate., Results: The operation time of cold flowable gutta-percha group was significantly lower than that of the control group, which were 51 s and 74 s ( P < 0.05); The percentages of pain and discomfort in the two groups were 26.67% and 40.00%, respectively. There were two cases of underfilling and no overfilling in both groups. The percentages of proper filling and tight three-dimensional obturation in the experimental and control groups were 71.11% and 60.00% respectively; and the percentages of tight three-dimensional obturation in the apical third areas were 86.67% and 66.67%, the difference was significant ( P < 0.05). There was no significant difference in the three-dimensional tightness between the two groups in the middle and coronal third areas. The percentages of tight three-dimensional obturation in classification Ⅰ groups were 86.67%, 83.33%, 93.33% and 76.67%, 90.00%, 96.67% in experimental and control group, respectively; The percentages of classification Ⅱ/Ⅲ/Ⅳ groups were 86.67%, 86.67%, 100.00% and 46.67%, 86.67%, 100.00%, respectively, and the difference was significant ( P < 0.05). There were no apical lesions that occurred in either group during the one-year review period., Conclusion: The application of cold flowable gutta-percha on young permanent teeth root canal obturation after apexification can achieve good obturation effect. The root obturation effect in the apical third area is significantly better than that of warm gutta-percha obturation techniques. Cold flowable gutta-percha can shorten the clinical treatment time and ameliorate the patients' therapy comfort.