平行与层叠铸造分瓣桩核冠修复的临床对比观察

目的：比较平行与层叠铸造分瓣桩核冠修复牙冠大部分缺损的恒磨牙,并观察比较两种桩核冠临床修复的效果。方法：对52颗经过完善根管治疗的大面积缺损的磨牙,均采用铸造分瓣桩核冠,其中27颗采用平行分瓣桩核冠修复,25颗采用层叠分瓣桩核冠修复,随访3年。结果：平行分瓣桩核冠修复与层叠分瓣桩核冠修复方法的成功率依次是96.3%和92.0%,两组之间经χ2检验,无显著性差异。结论：采用平行分瓣桩核冠和层叠分瓣桩核冠修复牙冠大部分缺损的磨牙,均可取得良好的临床效果。     

整体铸造和分瓣铸造桩核冠修复的临床对比观察

目的　比较整体铸造和分瓣铸造桩核冠修复后牙严重缺损的临床效果。方法　对 5 1颗经过完善根管充填后的严重缺损的后牙 ,35颗进行整体铸造桩核冠修复 ,16颗进行分瓣铸造桩核冠修复 ,并随访观察 2～ 3年。结果　两组桩核冠修复的临床效果无显著性差异 (P >0 .0 5 )。结论　整体铸造和分瓣铸造桩核冠用于修复后牙严重缺损均可取得良好的临床效果     

3种铸造桩核冠修复后牙的临床疗效观察

目的比较整体铸造、分瓣铸造和插销式铸造桩核冠修复后牙严重牙体缺损的临床效果。方法选择180例患者的193颗后牙残冠、残根,在修复前行完善的根管治疗,其中87颗采用整体铸造桩核冠,56颗采用分瓣铸造桩核冠,50颗采用插销式铸造桩核冠的方法修复后牙严重牙体缺损。通过对修复后2年的复查结果进行临床效果评价。结果3组铸造桩核冠修复的临床效果无显著性差异(P>0.01)。结论整体铸造、分瓣铸造和插销式铸造桩核冠用于修复后牙严重牙体缺损均可取得良好的临床效果。     

两种桩核冠修复磨牙残根的临床观察

目的:观察分瓣铸造桩核冠和成品螺纹桩树脂核冠在磨牙残根修复中的效果。方法:对69例严重缺损的磨牙,32例进行分瓣铸造桩核冠修复(A组),37例进行螺纹桩树脂核冠修复(B组),术后对其中61例残根随访2~3年。结果:54例使用良好(A组26例,B组28例),A组和B组的成功率分别为86%和90%,总成功率为88.5%。结论:两种桩核冠用于磨牙残根修复均可取得良好的临床效果。     

2种不同印模方法制取间接桩核的临床效果评价

目的比较硅橡胶印模法与琼脂/藻酸盐联合印模法制取铸造间接桩核的临床效果。方法将牙体大面积缺损、根管治疗后要求桩核冠修复的389颗牙随机分为A、B组,A组采用硅橡胶印模法制取间接桩核,B组采用琼脂/藻酸盐联合印模法制取间接桩核,对2种印模法制取间接桩核的效果进行评价。结果硅橡胶印模法制取间接桩核的临床成功率高于琼脂/藻酸盐联合印模法,二者之间差异具有统计学意义（P<0.05）。其中,2种不同印模方法制取前牙间接桩核的成功率之间差异无统计学意义（P>0.05）,制取前磨牙和磨牙间接桩核的成功率之间差异有统计学意义（P<0.05）。结论采用硅橡胶印模法制取间接桩核的临床效果优于琼脂/藻酸盐联合印模法。     

超声骨刀在上颌磨牙分根术及半切术中的应用

目的探讨上颌磨牙使用超声骨刀行分根术及半切术后行桩核冠修复的临床疗效。方法临床选择符合条件的18颗存在严重牙体缺损的上颌磨牙,完善根管治疗后应用超声骨刀行分根术或半切术,必要时做牙冠延长术,根分叉有炎症先行牙周治疗,而后行桩核联冠或腭侧单冠修复。随访2年。结果 1例患者于1年后失访,其余17颗患牙均能保持良好的咀嚼功能,患者无明显不适,X线片示牙槽骨无明显吸收。结论应用超声骨刀行分根术及半切术联合桩冠修复对治疗严重缺损上颌磨牙有良好的临床效果。     

三种形式桩核冠修复磨牙大面积缺损的临床研究

目的 采用成品桩-光敏树脂核冠、成品桩-汞核冠及铸造桩核冠修复大面积缺损的磨牙,观察并比较其临床修复效果。方法 对87颗经过完善根管充填的大面积缺损的磨牙,14颗用成品桩-树脂核冠,41颗用成品桩-汞核冠,32颗行铸造桩核-冠修复,对其临床效果随访2～3年。结果 成品桩-树脂核冠组有1例桩折断,1例继发龋,成品桩-汞核冠组有1例刺激性龈炎;铸造桩核冠组有1例根折,经统计学检验,汞核冠组及铸造桩核冠组修复效果无显著性差异,树脂核冠组与汞核冠及铸造桩冠组有1例根折,经统计学检验,汞核冠组及铸造桩核冠组修复效果无显著性差异,树脂核冠组与汞核冠及铸造桩冠组有显著性差异。结论 成品桩-汞核冠和铸造桩核冠修复大面积缺损磨牙的效果较成品桩-树脂核冠好。     

分体式桩核在磨牙修复中的应用

目的评估分体式桩核冠修复大面积牙体缺损磨牙的临床效果。方法对113例大面积牙体缺损的磨牙行分体式桩核冠修复,并进行跟踪调查,评估其临床修复效果。结果分体式桩核冠修复大面积牙体缺损磨牙的成功率达85.8%。结论分体式桩核冠是修复大面积牙体缺损磨牙的有效手段,其临床修复效果满意。     

纤维桩与插销桩修复磨牙严重缺损的临床研究

目的比较2种桩核材料用于磨牙严重缺损的修复效果。方法80颗磨牙缺损患牙随机分为2组,分别进行玻璃纤维桩核冠修复和铸造插销式分体桩核冠修复,2年后对修复效果进行评价。结果玻璃纤维桩组出现1颗冠折;插销式分体桩组所有患牙均未出现冠松动脱落、冠桩脱落、冠折、根折、桩折,2组差异无统计学意义(P<0.05)。结论对于磨严重牙缺损患者,选用玻璃纤维桩核冠修复或铸造插销式桩核冠修复均可,但对于缺损严重合并牙根条件差的患牙,选用玻璃纤维桩需慎重。     

超声骨刀在下颌磨牙分根术及半切术中的应用

目的:评价应用超声骨刀进行分根术及半切术后行桩核冠桥修复的临床疗效。方法:临床选择符合条件的27颗下颌磨牙进行完善的根管治疗后应用超声骨刀行分根术或半切术,必要时做冠延长术,根分叉有炎症先行牙周治疗,而后做桩核联冠或固定桥修复。随访2年。结果:除一颗患牙牙周炎进展导致牙周脓肿松动拔除外,其余26颗患牙均能保持良好的咀嚼功能,患者主观感受无明显不适,X片示牙槽骨无明显吸收或少量增生。结论:应用超声骨刀行牙分根术及半切术联合冠桥修复对治疗严重缺损下颌磨牙具有良好的临床效果。     

Fracture Resistances of Cast Metal and Ceramic Dowel and Core Restorations: A Pilot Study

PURPOSE: The purpose of this study was to compare fracture strengths of teeth restored with cast metal and ceramic dowel and cores supporting all-ceramic crowns. MATERIALS AND METHODS: Eighteen recently extracted teeth were randomly divided into 3 equal groups. Metal dowel and cores (MDC) were fabricated for 1 group using a base metal alloy, and served as the control. The other groups received In-Ceram Spinell (ICS) and IPS Empress 2 (IPS) dowel and cores. IPS Empress 1 crowns were fabricated for all samples. Each tooth was subjected to a shear force at a crosshead speed of 2 mm/min on a universal testing machine until failure occurred. RESULTS: The mean fracture strengths and standard deviations of MDC, ICS, and IPS restorations were 1101 N (361), 832 N (288), and 1137 N (367), respectively. The differences between groups were insignificant (p < 0.05). Fractures of the all-ceramic crowns were observed in the MDC group, whereas the failure of ceramic dowel and core restorations was associated with root fracture at the cervical region. CONCLUSIONS: Due to improved mechanical properties, In-Ceram Spinell and IPS Empress 2 ceramic dowel and cores may be candidates for the restoration of endodontically treated anterior teeth.     

Effect of Core Material and Restoration Design on Strength of Endodontically Treated Bovine Teeth: A Laboratory Study

Purpose: The purpose of this study was to evaluate the fracture resistance of bovine teeth restored with one-piece cast core/crowns and no ferrule, compared to teeth restored with amalgam cores and full coverage crowns, with and without a dentine ferrule.
Materials and Method: Thirty bovine incisors were selected and modified to ensure all teeth had axial dentine walls of similar size. The teeth were then randomly allocated to one of the three groups: control group restored with amalgam core and cast crown without ferrule; ferrule group restored with amalgam core and cast crown with a 2-mm dentine ferrule; one-piece group restored with one-piece cast core/crown without ferrule. Each tooth was loaded to the point of fracture.
Results: The mean load resisted by the control group, the ferrule group, and the one-piece group were 1092.5, 1843.5, and 1463.1 N, respectively. The mean load resisted by the ferrule group was significantly greater than the control group ( p < 0.001) and the one-piece cast core/crown group ( p = 0.04). The mean load resisted by the one-piece cast core/crown group was significantly greater than the control group ( p = 0.04).
Conclusions: The maximum load resistance was significantly enhanced by a 2-mm ferrule compared with teeth with no ferrule and teeth restored with one-piece cast core/crowns. Teeth restored with one-piece cast core/crowns were significantly more resistant to loading than teeth restored with amalgam cores and crowns without a ferrule.     

应用髓室固位的金属嵌体冠修复磨牙重度牙冠缺损

目的:评价利用髓室同位制作嵌体冠修复磨牙残冠的效果.方法:对61颗磨牙残冠经完善根管治疗后,制作髓室固位的铸造金属嵌体冠,修复完成后,定期进行临床检查,评价修复效果.结果:经过1～5a的随访观察,61颗患牙经过修复治疗后获得满意效果,个别病例出现修复体颈缘密合不良、牙龈炎.或继发龋、食物嵌塞.结论:利用髓室固位的铸造金属嵌体冠治疗磨牙残冠,是一种简单易行、经济实惠、效果良好的修复方法,严格选择适应证以及准确的牙体预备和精确的加工制作,是修复成功的关键.     

单根管与多根管铸造桩核用于磨牙残冠修复的比较研究

目的比较单根管与多根管铸造桩核冠修复磨牙残冠的临床效果。方法选择140例患者的153颗磨牙残冠,在修复前行完善的根管治疗,其中92颗采用单根管整体铸造桩核冠修复,61颗采用插销式铸造的多根管桩核冠修复。对修复后两年的复查结果进行临床效果评价。结果单根管固位修复体桩核松动1个,其余桩核X线片显示桩核与根管结合紧密,修复效果良好。多根管分体插销式铸造桩核冠无松动。修复的临床效果无显著性差异(P>0.05)。结论采用单根管铸造桩核修复磨牙残冠不仅制作简单,而且与多根管分体桩核修复无显著性差异,同样可取得良好的临床效果。     

Comparative evaluation of fracture resistance of structurally compromised canals restored with different dowel methods

Purpose: The objective of this in vitro study was to evaluate and compare the fracture resistance and fracture mode of endodontically treated teeth with wide root canals restored with various dowel methods. Materials and Methods: Fifty human uniradicular mandibular premolar teeth were decoronated and endodontically treated. The canals were widened with diamond points. The specimens were divided into five groups on the basis of type of dowel method used: conventional custom‐made cast metal dowel; single glass fiber‐reinforced resin dowel; glass fiber‐reinforced resin dowel with accessory fiber dowels; relined glass fiber‐reinforced resin dowel; and dowels formed with the help of polyethylene fiber ribbon‐reinforced resin composite. Specimens were restored with indirect composite crowns, and 150,000 cycles of cyclic loading were applied. The specimens were loaded to test the fracture resistance and fracture mode (repairable and nonrepairable). Results: The cast metal dowel groups had the highest fracture resistance but showed nonrepairable fracture in 90% of specimens. Conclusions: Cast metal dowels had the highest fracture resistance but led to nonrepairable fracture while restoring the wide root canals under cyclic loading. Specimens restored with fiber dowels, accessory dowels, relined dowels, and ribbon‐reinforced resin provided adequate fracture resistance with increased incidence of repairable fractures.     

Clinical success of zirconium oxide posts with resin composite or glass-ceramic cores in endodontically treated teeth: a 4-year retrospective study

PURPOSE: This study retrospectively evaluated zirconium oxide posts with either direct resin composite cores or indirect glass-ceramic cores after several years of clinical service. MATERIALS AND METHODS: One hundred forty-five endodontically treated teeth in 88 patients were restored with zirconium oxide posts; 87 teeth were restored with direct composite cores, and 58 were restored with Empress cores prior to crowning. Seventy-nine posts with direct composite cores in 52 patients and 34 posts with glass-ceramic cores in 19 patients were reevaluated clinically and radiographically after a mean clinical service of 57.7 months and 46.3 months, respectively. RESULTS: Periodontal probing depths remained on a healthy clinical level, and esthetics were judged excellent for the majority of teeth in both groups. In the group with direct composite cores, no failures were observed in the 79 posts that were reevaluated. In the group with indirect glass-ceramic cores, three failures were observed after 42, 43, and 55 months of clinical service. All failures were due to loss of retention. In a best-case scenario posts that could not be reevaluated were considered successful, and in a worst-case scenario they were considered failures; respective success rates were 100% and 91% in the direct group and 95% and 53% in the indirect group. CONCLUSION: The observed clinical success of zirconium oxide posts with direct composite cores suggests that this method of post-and-core reconstruction is clinically promising. Zirconium oxide posts with indirect glass-ceramic cores displayed a significantly higher failure rate and a high dropout rate that precludes valid conclusions.     

桩核修复方法对梭形根管牙断裂强度的影响

目的：比较3种不同桩核修复方法对梭形根管牙断裂强度的影响。方法：30颗近期拔除的上颌中切牙根管治疗后预备成梭形,随机分为3组,每组10颗。Ⅰ组行玻璃纤维桩、Luxacore树脂核和铸造全冠修复;Ⅱ组根管扩大预备后行铸造镍铬桩核和铸造全冠修复;Ⅲ组玻璃离子水门汀重塑根管后行铸造镍铬桩核和铸造全冠修复。Zwick z010型电子万能试验机测试断裂强度。结果：Ⅰ组与Ⅱ组、Ⅲ组试件牙的断裂强度差异有显著性,Ⅱ组与Ⅲ组差异无显著性。结论：梭形根管牙的断裂强度与其修复设计有关,采用玻璃纤维桩及树脂核修复有较高的断裂强度,且断裂方式利于再修复。     

In vitro investigation on extensively destroyed vital teeth: is fracture force a limiting factor for direct restoration?

To evaluate the in vitro fracture load of extensively damaged vital teeth after either direct or indirect restauration, severe tooth substance loss was simulated for 96 molars. Subsequently, two cavities were prepared with little (design 1) or more substantial (design 2) residual tooth support. All molars were provided with a 2‐mm ferrule design and then divided into 12 test groups based on their occlusal surface size. They were restored with composite or with either of two types of single crown (cast metal or milled zirconia). After thermal ageing (10 000 cycles at 6·5 and 60 °C), 1·2 million cycles of chewing simulation were applied (64 N). Maximum fracture load was determined with a loading angle of 45°. Statistical analysis was performed by use of Kaplan–Meier modelling, Student's t‐tests, one‐way anova , post hoc Tukey's HSD tests and linear regression analysis. Regarding mean fracture load without ageing, the indirect restorations outperformed composite (design 1: direct: 508 ± 123 N, indirect: 741 ± 248 N; design 2: direct: 554 ± 167 N, indirect: 903 ± 221 N). After artificial ageing, however, these differences were no longer significant (design 1: direct: 328 ± 189 N, indirect: 506 ± 352 N; design 2: direct 399 ± 208 N, indirect 577 ± 292 N). Instead, the fracture load of the aged composite restorations was comparable with that for zirconia (design 1) and cast metal (design 2) crowns. Fracture loads of direct composite restorations after artificial ageing might fulfil clinical requirements.