Masticatory hypofunction and soft food affect the tooth rows, occlusion, and jawbone. This study aimed to clarify the influence of tooth loss and a soft diet <span>on morphology of the tooth root during the grow...Masticatory hypofunction and soft food affect the tooth rows, occlusion, and jawbone. This study aimed to clarify the influence of tooth loss and a soft diet <span>on morphology of the tooth root during the growth period. We divided</span><span> 3-week-</span><span>old Wistar rats into the following three groups: Hard diet group (rats raised on solid standard diet), Powder diet group (rats raised on powdered standard feed diet), and Extraction group (rats raised on powdered standard diet with maxillary molars extraction). Length, width, cross-sectional area, and volume </span><span>of the root of the mandibular M1 and M2 were measured using micro-CT</span><span> analysis. Non-decalcified thin-slice specimens of sagittal sections of the M1 were obtained at the age of 20 weeks, and the roots were observed. The root length of all roots in the Extraction group was significantly longer than that in the other groups. The root width and cross-sectional area at the apical side 1/4 of all roots in the Extraction group were significantly smaller than those in the other groups. The root volume of the M1 mesial root in the Extraction group was significantly smaller than that in the other groups.</span><span> </span><span>This study clarified that when masticatory stimulus in the immature teeth is reduced by the extraction of opposing teeth and a powder diet, the root length increases due </span><span>to the promotion of cellular cementum addition at the apex, and the root</span><span> width and cross-sectional area decrease due to the suppression of cellular cementum addition at the apical side 1/4 of the roots.</span>展开更多
When the gearbox body interference is connected to the ring gear, prestressing occurs in the ring gear, which has a significant impact on the strength and life of the gear. Research on the prestressing of the inner ri...When the gearbox body interference is connected to the ring gear, prestressing occurs in the ring gear, which has a significant impact on the strength and life of the gear. Research on the prestressing of the inner ring gear is in the preliminary stage, and the distribution rule of the prestressing and the influence of each parameter on the interference prestressing have not been derived. In this paper, based on the method of calculating the prestressing of the thick cylinder in interference fit, the ring gear is found to be equivalent to a thick cylinder, and the distribution rule of prestressing of the ring gear in the interference fit is inferred. Then, by modeling and analyzing the gearbox body and ring gear in the interference fit using ABAQUS, the distribution rule of prestressing the ring gear in the interference fit is obtained through a numerical simulation. Finally, the prestressing of the ring gear in the interference fit is measured using X-ray di raction, and the distribution rule of prestressing of the ring gear in the interference fit is obtained through analysis. Compared with the distribution rule of prestressing in theory, numerical simulation, and experiment, the theoretical distribution rule of prestressing is amended through a statistical method, and a more accurate formula of prestressing is obtained. Through the calculation of the stress and bending moment in the dangerous section of the ring gear through prestressing, the formula for checking the tooth root flexural fatigue strength in the interference fit prestressing is inferred. This research proposes a tooth root bending strength conditional formula for the inner ring gear of the interference fit, which serves as a guide for the design and production of the actual interference joint inner ring gear.展开更多
The root is crucial for the physiological function of the tooth, and a healthy root allows an artificial crown to function as required clinically. Tooth crown development has been studied intensively during the last f...The root is crucial for the physiological function of the tooth, and a healthy root allows an artificial crown to function as required clinically. Tooth crown development has been studied intensively during the last few decades, but root development remains not well understood. Here we review the root development processes, including cell fate determination, induction of odontoblast and cementoblast differentiation, interaction of root epithelium and mesenchyme, and other molecular mechanisms. This review summarizes our current understanding of the signaling cascades and mechanisms involved in root development. It also sets the stage for de novo tooth regeneration.展开更多
Tooth formation is a highly orchestrated process that precisely regulates the size and shape of the tooth.During typical tooth development,Hertwig’s epithelial root sheath(HERS)interacts with mesenchymal cells to dir...Tooth formation is a highly orchestrated process that precisely regulates the size and shape of the tooth.During typical tooth development,Hertwig’s epithelial root sheath(HERS)interacts with mesenchymal cells to direct the elongation of the tooth root and the deposition of dentin and cementum,thereby contributing to the formation of a fully developed tooth root.BMP9,a member of the BMP family,plays a significant role in growth,development,and cell differentiation.However,the precise function of BMP9 in dental root development remains unclear,particularly regarding its influence on HERS and odontoblasts.In this study,we utilized a mouse molar model to investigate the role of BMP9 signaling in tooth root development.The tooth formation of Bmp9 knockout(Bmp9-KO)mice and wild-type(WT)littermates was compared.Our findings revealed that Bmp9-KO mice exhibited shorter mandibular first molar roots,wider apical foramina,and thinner dentin compared with WT mice by micro-CT and hematoxylin-eosin staining analysis.Additionally,the results of immunohistochemistry and quantitative PCR indicated that in the absence of Bmp9,odontoblast differentiation and secretory function were compromised.Furthermore,Bmp9 ablation resulted in reduced cell proliferation and increased intercellular junctions within HERS,subsequently impacting root dentin formation and apical foramen closure.This study offers new insights into the regulatory role of BMP9 signaling in odontoblast and HERS function,highlighting its significance in root development and providing potential avenues for future research in tooth root regeneration.展开更多
目的:观察iRoot BP Plus根尖屏障术治疗慢性根尖周炎伴根尖孔未闭合患者的效果。方法:回顾性分析2022年1月至2024年1月该院收治的84例慢性根尖周炎伴根尖孔未闭合患者的临床资料,依据治疗方案不同将其分为对照组和研究组各42例。对照组...目的:观察iRoot BP Plus根尖屏障术治疗慢性根尖周炎伴根尖孔未闭合患者的效果。方法:回顾性分析2022年1月至2024年1月该院收治的84例慢性根尖周炎伴根尖孔未闭合患者的临床资料,依据治疗方案不同将其分为对照组和研究组各42例。对照组采用三氧化物聚合物(MTA)根尖屏障术治疗,研究组采用iRoot BP Plus根尖屏障术治疗,比较两组治疗效果、临床相关指标(操作时间、术后疼痛时间)水平、治疗前后根尖周指数(PAI)评分和患牙保留率。结果:两组治疗总有效率比较,差异无统计学意义(P>0.05);研究组操作时间、术后疼痛时间均短于对照组,差异有统计学意义(P<0.05);治疗后,两组PAI评分均低于治疗前,且研究组低于对照组,差异有统计学意义(P<0.05);研究组患牙保留率高于对照组,差异有统计学意义(P<0.05)。结论:iRoot BP Plus根尖屏障术治疗慢性根尖周炎伴根尖孔未闭合患者可提高患牙保留率,缩短操作时间与术后疼痛时间,以及降低PAI评分的效果优于MTA根尖屏障术。展开更多
A series of changes occur in the remaining alveolar process after whole tooth extraction.The basic question is,why do the bony walls(especially the labial/buccal)get resorbed immediately after the tooth is removed?Thi...A series of changes occur in the remaining alveolar process after whole tooth extraction.The basic question is,why do the bony walls(especially the labial/buccal)get resorbed immediately after the tooth is removed?This could be because,with cementum of the concerned tooth and its periodontal ligament,the supporting bundle bone is dependent on the presence of the tooth.This loss can be compensated using numerous techniques,such as socket grafting using various biomaterials to preserve the alveolar bone and buccal grafting with guided tissue regeneration to increase the thickness of buccal bone or placement of implant immediately.However,none of these techniques prevent the modelling of the alveolar bone post-extraction.Few studies have demonstrated that preservation of the roots in the alveolar process maintains the bone volume and facilitates vertical bone growth.A histological study in animals and humans has shown that the retained root shell does not pose any interference in the osseointegration of the implant(if placed simultaneously).Although various names have been proposed to describe the concept of retaining full or part of the root to prevent the resorption of the ridge,socket-shield and pontic-shield are the two most commonly used terms worldwide.The extraction of the whole tooth might be the choice of therapy when socket-shield or pontic-shield is not possible due to anatomical variations,infections,or lack of clinical expertise.Irrespective of the size,when a whole root or a root fragment(is left in situ),it is the dentist’s ethical duty to advise/inform the patient and ensure repeated clinical and radiographic follow-up.The present study aimed to highlight the current status of these techniques,their benefits,and possible complications and address whether the paradigm of the teeth extraction methods should be altered.展开更多
Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment a...Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each （A/B/C） to 3 experimental groups （7 rats, 112/3）. （A） cone-beam-computed tomography （CBCT）; （B） histology/serology; （C） reverse- transcription quantitative real-time polymerase chain reaction （RT-qPCR）/cotinine serology--（1） control; （2） orthodontic tooth movement （OTM） of the first and second upper left molar （NiTi closed coil spring, 0.25 N）; （3） OTM with 1.89 mg-kg- 1 per day s.c. of L（- ）-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption （OIIRR）, osteoclast activity （histology）, orthodontic tooth movement velocity （CBCT, within 14 and 28 days of OTM） and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue （RT-qPCR）. Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.展开更多
目的:体外评价新型根尖倒充填材料iRoot BP plus和iRoot FS的生物学性能。方法:(1)将牙根预备成长3 mm、根管直径1 mm的试样,分别于根管内填充iRoot BP plus、iRoot FS和三氧化矿物凝聚体(mineral trioxide aggregate,MTA)。将制备好的...目的:体外评价新型根尖倒充填材料iRoot BP plus和iRoot FS的生物学性能。方法:(1)将牙根预备成长3 mm、根管直径1 mm的试样,分别于根管内填充iRoot BP plus、iRoot FS和三氧化矿物凝聚体(mineral trioxide aggregate,MTA)。将制备好的试样置于模拟体液(simulated body fluid,SBF)中,用扫描电子显微镜观察暴露的材料表面矿物沉积情况,并通过X射线能谱对其表面形成的晶体进行元素分析,测定SBF的p H值随时间的变化。(2)将iRoot BP plus、iRoot FS和MTA制备成直径8 mm、高度2 mm的圆柱,制备DMEM浸提液,通过MTT实验观察材料对MG63细胞增殖活性的影响,并通过实时荧光定量PCR和碱性磷酸酶(alkaline phosphatase,ALP)染色分析材料对ALP基因及蛋白表达的影响。结果:(1)在SBF中浸泡24 h时,iRoot BP plus、iRoot FS和MTA表面均已有矿物沉积,14 d后有大量矿物沉积,钙∶磷比值分别为1.43、1.39和1.51;(2)iRoot BP plus、iRoot FS和MTA均可使SBF的p H升高,3周时分别为8.09±0.07、7.91±0.06和8.11±0.06;(3)以体积比为1∶5和1∶10稀释的iRoot BP plus、iRoot FS和MTA浸提液对MG63细胞的增殖无明显促进或抑制作用;(4)iRoot BP plus、iRoot FS和MTA组对MG63细胞ALP基因的表达均具有促进作用,ALP染色各组未见明显差异。结论:iRoot在模拟体液中可诱导矿物质沉积,促进MG63细胞的分化和矿化,具有良好的生物活性和促成骨作用。展开更多
目的研究iRoot BP Plus用于外伤露髓年轻恒牙活髓切断术对牙齿变色率及根管钙化的影响。方法选取2018年1月至2020年6月于本院行活髓切断术的82例患儿,随机分为对照组(使用MTA盖髓材料)和观察组(使用iRoot BP Plus盖髓材料)各41例,随访1...目的研究iRoot BP Plus用于外伤露髓年轻恒牙活髓切断术对牙齿变色率及根管钙化的影响。方法选取2018年1月至2020年6月于本院行活髓切断术的82例患儿,随机分为对照组(使用MTA盖髓材料)和观察组(使用iRoot BP Plus盖髓材料)各41例,随访1年,比较两组不同时间的手术疗效、根管钙化和牙齿变色情况,以及手术时间、肿胀时间和疼痛持续时间、牙齿功能和美观度,并记录两组患儿术后并发症。结果两组术后3个月、末次随访的疗效差异无统计学意义(P>0.05);观察组肿胀时间、术后疼痛持续时间短于对照组(P<0.05);观察组的舒适、固定和美观评分高于对照组(P<0.05);术后6个月及末次随访观察组的根管钙化和牙齿变色率低于对照组(P<0.05);观察组的并发症发生率为2.44%,低于对照组的14.63%(P<0.05)。结论iRoot BP Plus与MTA均能较好地用于外伤露髓年轻恒牙的牙髓切断术,其中iRoot BP Plus能减少根管钙化、牙齿变色情况,应用前景良好。展开更多
目的观察iRoot Bp Plus作为盖髓剂,在活髓切断术中治疗感染性畸形中央尖的临床效果。方法将2018年10月—2019年12月在医院就诊,因畸形中央尖折断或磨损后继发牙髓感染的年轻恒牙为研究对象,共26颗,按就诊顺序将患者分为试验组(13颗)和...目的观察iRoot Bp Plus作为盖髓剂,在活髓切断术中治疗感染性畸形中央尖的临床效果。方法将2018年10月—2019年12月在医院就诊,因畸形中央尖折断或磨损后继发牙髓感染的年轻恒牙为研究对象,共26颗,按就诊顺序将患者分为试验组(13颗)和对照组(13颗)。试验组使用iRoot BP Plus进行活髓切断术,对照组使用氢氧化钙糊剂进行活髓切断术。比较两组活髓切断术后1、3、6、12个月复查,观察术后症状、钙化桥形成及牙根发育等,计算两组患儿临床及影像学成功率。结果试验组患者术后1、3、6、12个月复查术后症状明显低于对照组,而钙化桥形成率则高于对照组,差异有统计学意义(P<0.05)。两组患者在术后1个月、3个月时的复查临床及影像学成功率相比,差异无统计学意义(P>0.05)。在术后6、12个月时试验组复查临床及影像学成功率明显高于对照组,差异有统计学意义(P<0.05)。结论在感染性畸形中央尖活髓切断术中,运用iRoot Bp Plus进行活髓切断,可明显的减少术后的不良症状,促进患牙的钙化桥形成及牙根发育,提升患儿的临床及影像学成功率,获得较好的效果。展开更多
文摘Masticatory hypofunction and soft food affect the tooth rows, occlusion, and jawbone. This study aimed to clarify the influence of tooth loss and a soft diet <span>on morphology of the tooth root during the growth period. We divided</span><span> 3-week-</span><span>old Wistar rats into the following three groups: Hard diet group (rats raised on solid standard diet), Powder diet group (rats raised on powdered standard feed diet), and Extraction group (rats raised on powdered standard diet with maxillary molars extraction). Length, width, cross-sectional area, and volume </span><span>of the root of the mandibular M1 and M2 were measured using micro-CT</span><span> analysis. Non-decalcified thin-slice specimens of sagittal sections of the M1 were obtained at the age of 20 weeks, and the roots were observed. The root length of all roots in the Extraction group was significantly longer than that in the other groups. The root width and cross-sectional area at the apical side 1/4 of all roots in the Extraction group were significantly smaller than those in the other groups. The root volume of the M1 mesial root in the Extraction group was significantly smaller than that in the other groups.</span><span> </span><span>This study clarified that when masticatory stimulus in the immature teeth is reduced by the extraction of opposing teeth and a powder diet, the root length increases due </span><span>to the promotion of cellular cementum addition at the apex, and the root</span><span> width and cross-sectional area decrease due to the suppression of cellular cementum addition at the apical side 1/4 of the roots.</span>
基金Supported by Hunan Provincial Natural Science Foundation of China(Grant No.2018JJ4006)National Independent Innovation Demonstration Area Foundation of Changsha Zhuzhou Xiangtan(Grant No.2018XK2302)
文摘When the gearbox body interference is connected to the ring gear, prestressing occurs in the ring gear, which has a significant impact on the strength and life of the gear. Research on the prestressing of the inner ring gear is in the preliminary stage, and the distribution rule of the prestressing and the influence of each parameter on the interference prestressing have not been derived. In this paper, based on the method of calculating the prestressing of the thick cylinder in interference fit, the ring gear is found to be equivalent to a thick cylinder, and the distribution rule of prestressing of the ring gear in the interference fit is inferred. Then, by modeling and analyzing the gearbox body and ring gear in the interference fit using ABAQUS, the distribution rule of prestressing the ring gear in the interference fit is obtained through a numerical simulation. Finally, the prestressing of the ring gear in the interference fit is measured using X-ray di raction, and the distribution rule of prestressing of the ring gear in the interference fit is obtained through analysis. Compared with the distribution rule of prestressing in theory, numerical simulation, and experiment, the theoretical distribution rule of prestressing is amended through a statistical method, and a more accurate formula of prestressing is obtained. Through the calculation of the stress and bending moment in the dangerous section of the ring gear through prestressing, the formula for checking the tooth root flexural fatigue strength in the interference fit prestressing is inferred. This research proposes a tooth root bending strength conditional formula for the inner ring gear of the interference fit, which serves as a guide for the design and production of the actual interference joint inner ring gear.
基金supported by grants from the NIDCR, NIH (DE012711 and DE014078) to Yang ChaiNational Natural Science Foundation of China (81170943)+1 种基金Beijing Natural Science Foundation (7122051)Funding for Talents in Beijing (D) (2010D003034000012) to Xiao-Feng Huang
文摘The root is crucial for the physiological function of the tooth, and a healthy root allows an artificial crown to function as required clinically. Tooth crown development has been studied intensively during the last few decades, but root development remains not well understood. Here we review the root development processes, including cell fate determination, induction of odontoblast and cementoblast differentiation, interaction of root epithelium and mesenchyme, and other molecular mechanisms. This review summarizes our current understanding of the signaling cascades and mechanisms involved in root development. It also sets the stage for de novo tooth regeneration.
基金supported by the National Natural Science Foundation of China(No.82470977 to H.Z.,No.32070539 to W.L.)sponsored by the Natural Science Foundation of Chongqing,China(No.2024ZYYB005 to H.Z.).
文摘Tooth formation is a highly orchestrated process that precisely regulates the size and shape of the tooth.During typical tooth development,Hertwig’s epithelial root sheath(HERS)interacts with mesenchymal cells to direct the elongation of the tooth root and the deposition of dentin and cementum,thereby contributing to the formation of a fully developed tooth root.BMP9,a member of the BMP family,plays a significant role in growth,development,and cell differentiation.However,the precise function of BMP9 in dental root development remains unclear,particularly regarding its influence on HERS and odontoblasts.In this study,we utilized a mouse molar model to investigate the role of BMP9 signaling in tooth root development.The tooth formation of Bmp9 knockout(Bmp9-KO)mice and wild-type(WT)littermates was compared.Our findings revealed that Bmp9-KO mice exhibited shorter mandibular first molar roots,wider apical foramina,and thinner dentin compared with WT mice by micro-CT and hematoxylin-eosin staining analysis.Additionally,the results of immunohistochemistry and quantitative PCR indicated that in the absence of Bmp9,odontoblast differentiation and secretory function were compromised.Furthermore,Bmp9 ablation resulted in reduced cell proliferation and increased intercellular junctions within HERS,subsequently impacting root dentin formation and apical foramen closure.This study offers new insights into the regulatory role of BMP9 signaling in odontoblast and HERS function,highlighting its significance in root development and providing potential avenues for future research in tooth root regeneration.
文摘目的:观察iRoot BP Plus根尖屏障术治疗慢性根尖周炎伴根尖孔未闭合患者的效果。方法:回顾性分析2022年1月至2024年1月该院收治的84例慢性根尖周炎伴根尖孔未闭合患者的临床资料,依据治疗方案不同将其分为对照组和研究组各42例。对照组采用三氧化物聚合物(MTA)根尖屏障术治疗,研究组采用iRoot BP Plus根尖屏障术治疗,比较两组治疗效果、临床相关指标(操作时间、术后疼痛时间)水平、治疗前后根尖周指数(PAI)评分和患牙保留率。结果:两组治疗总有效率比较,差异无统计学意义(P>0.05);研究组操作时间、术后疼痛时间均短于对照组,差异有统计学意义(P<0.05);治疗后,两组PAI评分均低于治疗前,且研究组低于对照组,差异有统计学意义(P<0.05);研究组患牙保留率高于对照组,差异有统计学意义(P<0.05)。结论:iRoot BP Plus根尖屏障术治疗慢性根尖周炎伴根尖孔未闭合患者可提高患牙保留率,缩短操作时间与术后疼痛时间,以及降低PAI评分的效果优于MTA根尖屏障术。
文摘A series of changes occur in the remaining alveolar process after whole tooth extraction.The basic question is,why do the bony walls(especially the labial/buccal)get resorbed immediately after the tooth is removed?This could be because,with cementum of the concerned tooth and its periodontal ligament,the supporting bundle bone is dependent on the presence of the tooth.This loss can be compensated using numerous techniques,such as socket grafting using various biomaterials to preserve the alveolar bone and buccal grafting with guided tissue regeneration to increase the thickness of buccal bone or placement of implant immediately.However,none of these techniques prevent the modelling of the alveolar bone post-extraction.Few studies have demonstrated that preservation of the roots in the alveolar process maintains the bone volume and facilitates vertical bone growth.A histological study in animals and humans has shown that the retained root shell does not pose any interference in the osseointegration of the implant(if placed simultaneously).Although various names have been proposed to describe the concept of retaining full or part of the root to prevent the resorption of the ridge,socket-shield and pontic-shield are the two most commonly used terms worldwide.The extraction of the whole tooth might be the choice of therapy when socket-shield or pontic-shield is not possible due to anatomical variations,infections,or lack of clinical expertise.Irrespective of the size,when a whole root or a root fragment(is left in situ),it is the dentist’s ethical duty to advise/inform the patient and ensure repeated clinical and radiographic follow-up.The present study aimed to highlight the current status of these techniques,their benefits,and possible complications and address whether the paradigm of the teeth extraction methods should be altered.
基金the ReForM-A-research funding programme of the Faculty of Medicine(University of Regensburg)for their financial supportsupported by a ReForM-A grant from the ReForM research funding programme of the Faculty of Medicine of the University of Regensburg,Germany(Kirschneck 31 March 2015)the German Research Foundation(DFG)within the funding programme Open Access Publishing
文摘Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each （A/B/C） to 3 experimental groups （7 rats, 112/3）. （A） cone-beam-computed tomography （CBCT）; （B） histology/serology; （C） reverse- transcription quantitative real-time polymerase chain reaction （RT-qPCR）/cotinine serology--（1） control; （2） orthodontic tooth movement （OTM） of the first and second upper left molar （NiTi closed coil spring, 0.25 N）; （3） OTM with 1.89 mg-kg- 1 per day s.c. of L（- ）-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption （OIIRR）, osteoclast activity （histology）, orthodontic tooth movement velocity （CBCT, within 14 and 28 days of OTM） and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue （RT-qPCR）. Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.
文摘目的:体外评价新型根尖倒充填材料iRoot BP plus和iRoot FS的生物学性能。方法:(1)将牙根预备成长3 mm、根管直径1 mm的试样,分别于根管内填充iRoot BP plus、iRoot FS和三氧化矿物凝聚体(mineral trioxide aggregate,MTA)。将制备好的试样置于模拟体液(simulated body fluid,SBF)中,用扫描电子显微镜观察暴露的材料表面矿物沉积情况,并通过X射线能谱对其表面形成的晶体进行元素分析,测定SBF的p H值随时间的变化。(2)将iRoot BP plus、iRoot FS和MTA制备成直径8 mm、高度2 mm的圆柱,制备DMEM浸提液,通过MTT实验观察材料对MG63细胞增殖活性的影响,并通过实时荧光定量PCR和碱性磷酸酶(alkaline phosphatase,ALP)染色分析材料对ALP基因及蛋白表达的影响。结果:(1)在SBF中浸泡24 h时,iRoot BP plus、iRoot FS和MTA表面均已有矿物沉积,14 d后有大量矿物沉积,钙∶磷比值分别为1.43、1.39和1.51;(2)iRoot BP plus、iRoot FS和MTA均可使SBF的p H升高,3周时分别为8.09±0.07、7.91±0.06和8.11±0.06;(3)以体积比为1∶5和1∶10稀释的iRoot BP plus、iRoot FS和MTA浸提液对MG63细胞的增殖无明显促进或抑制作用;(4)iRoot BP plus、iRoot FS和MTA组对MG63细胞ALP基因的表达均具有促进作用,ALP染色各组未见明显差异。结论:iRoot在模拟体液中可诱导矿物质沉积,促进MG63细胞的分化和矿化,具有良好的生物活性和促成骨作用。
文摘目的研究iRoot BP Plus用于外伤露髓年轻恒牙活髓切断术对牙齿变色率及根管钙化的影响。方法选取2018年1月至2020年6月于本院行活髓切断术的82例患儿,随机分为对照组(使用MTA盖髓材料)和观察组(使用iRoot BP Plus盖髓材料)各41例,随访1年,比较两组不同时间的手术疗效、根管钙化和牙齿变色情况,以及手术时间、肿胀时间和疼痛持续时间、牙齿功能和美观度,并记录两组患儿术后并发症。结果两组术后3个月、末次随访的疗效差异无统计学意义(P>0.05);观察组肿胀时间、术后疼痛持续时间短于对照组(P<0.05);观察组的舒适、固定和美观评分高于对照组(P<0.05);术后6个月及末次随访观察组的根管钙化和牙齿变色率低于对照组(P<0.05);观察组的并发症发生率为2.44%,低于对照组的14.63%(P<0.05)。结论iRoot BP Plus与MTA均能较好地用于外伤露髓年轻恒牙的牙髓切断术,其中iRoot BP Plus能减少根管钙化、牙齿变色情况,应用前景良好。
文摘目的观察iRoot Bp Plus作为盖髓剂,在活髓切断术中治疗感染性畸形中央尖的临床效果。方法将2018年10月—2019年12月在医院就诊,因畸形中央尖折断或磨损后继发牙髓感染的年轻恒牙为研究对象,共26颗,按就诊顺序将患者分为试验组(13颗)和对照组(13颗)。试验组使用iRoot BP Plus进行活髓切断术,对照组使用氢氧化钙糊剂进行活髓切断术。比较两组活髓切断术后1、3、6、12个月复查,观察术后症状、钙化桥形成及牙根发育等,计算两组患儿临床及影像学成功率。结果试验组患者术后1、3、6、12个月复查术后症状明显低于对照组,而钙化桥形成率则高于对照组,差异有统计学意义(P<0.05)。两组患者在术后1个月、3个月时的复查临床及影像学成功率相比,差异无统计学意义(P>0.05)。在术后6、12个月时试验组复查临床及影像学成功率明显高于对照组,差异有统计学意义(P<0.05)。结论在感染性畸形中央尖活髓切断术中,运用iRoot Bp Plus进行活髓切断,可明显的减少术后的不良症状,促进患牙的钙化桥形成及牙根发育,提升患儿的临床及影像学成功率,获得较好的效果。
