S Zhabuawala Murtuza, R Nadig Roopa, S Pai Veena, Gowda Yashwanth, M Aswathanarayana Ranjini
Postgraduate Student, Department of Conservative Dentistry and Endodontics Dayananda Sagar College of Dental Sciences, Bengaluru Karnataka, India.
Professor and Head, Department of Conservative Dentistry and Endodontics Dayananda Sagar College of Dental Sciences, Bengaluru Karnataka, India.
Int J Clin Pediatr Dent. 2017 Oct-Dec;10(4):351-357. doi: 10.5005/jp-journals-10005-1464. Epub 2017 Feb 27.
To evaluate the fracture resistance of simulated immature teeth with an apical plug of biodentine followed by composite resin vs total obturation with biodentine tested immediately and after 3 months of aging and also to find out the chemical composition of dentin in contact with these materials.
Extracted human maxillary central incisors with simulated immature apex with radicular dentin thickness (RDT) of 1 to 1.5 mm selected and divided into three groups of 20 each. Group I (control)-4 mm biodentine apically and thermoplasticized gutta-percha. Group II-4 mm biodentine apically and composite resin. Group III-complete obturation with biodentine. About 10 samples from each group were tested immediately and remaining 10 stored in phosphate buffered solution (PBS) and tested after 3 months for fracture resistance and chemical analysis of dentin.
No significant difference in fracture resistance between the groups was observed when tested immediately. After 3 months of aging, only biodentine group showed a significant reduction in fracture resistance with increased Ca/P ratio of root dentine.
Biodentine group has shown drastic reduction in fracture resistance after 3 months of aging, and hence, cannot be recommended as a reinforcement material in immature teeth with thin dentin walls. Zhabuawala MS, Nadig RR, Pai VS, Gowda Y, Aswathanarayana RM. Reinforcing Effects of Calcium Silicate-based Cement and Dual Cure Composite Resin in Simulated Immature Teeth with an Open Apex: An Study. Int J Clin Pediatr Dent 2017;10(4):351-357.
评估采用生物活性玻璃陶瓷根尖充填后再用复合树脂修复的模拟未成熟恒牙与即刻及老化3个月后采用生物活性玻璃陶瓷进行全封闭处理的模拟未成熟恒牙的抗折性能，并探究与这些材料接触的牙本质的化学成分。
选取拔除的具有模拟未成熟根尖、根管牙本质厚度（RDT）为1至1.5毫米的人类上颌中切牙，并将其分为三组，每组20颗。第一组（对照组）——根尖用4毫米生物活性玻璃陶瓷并热塑牙胶充填。第二组——根尖用4毫米生物活性玻璃陶瓷并复合树脂修复。第三组——用生物活性玻璃陶瓷进行全封闭充填。每组约10个样本即刻进行抗折性能测试，其余10个样本保存在磷酸盐缓冲溶液（PBS）中，3个月后进行抗折性能测试及牙本质的化学分析。
即刻测试时，各组间抗折性能无显著差异。老化3个月后，仅生物活性玻璃陶瓷组的抗折性能显著降低，且牙根牙本质的钙磷比增加。
生物活性玻璃陶瓷组在老化3个月后抗折性能急剧下降，因此，不推荐将其作为牙本质壁薄的未成熟恒牙的增强材料。扎布瓦拉·M·S、纳迪格·R·R、派·V·S、高达·Y、阿斯瓦塔纳拉亚纳·R·M。基于硅酸钙的水门汀和双固化复合树脂对模拟开放根尖未成熟恒牙的增强作用：一项研究。《国际临床儿科牙科学杂志》2017年；10（4）：351 - 357。
