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2008年第31卷第3期 目录
反3/4冠抗切向脱位力的实验研究
丁农乐，杨 正
（泸州医学院附属口腔医院修复科，四川泸州 646000）
摘 要 目的：通过测量并比较金属3/4冠与金属烤瓷反3/4冠修复离体上颌中切牙抗切向脱位力的差异，论证金属烤瓷反3/4冠的抗切向脱位力能否满足临床固位要求。方法：选择20颗牙冠完整的离体上颌中切牙行牙体预备，制作金属3/4冠并就位于对应离体牙上，用万能试验机测量并统计各个样本的切向脱位力。再对20颗离体上颌中切牙行牙体预备，制作金属烤瓷反3/4冠金属底冠并就位于对应离体牙上，用万能试验机测量并统计各个样本的切向脱位力。用SPSS14.0统计软件包对测量结果进行配对T检验(parired-samples
T Test)。结果：①金属3/4冠的切向脱位力为0.545±0.487N。②金属烤瓷反3/4冠金属底冠的切向脱位力为2.96±1.58N。③金属3/4冠的抗切向脱位力和金属烤瓷反3/4冠金属底冠的切向脱位力差异有显著统计学意义(P<0.01)。后者抗切向脱位力大于前者。结论：金属烤瓷反3/4冠修复离体上颌中切牙，其抗切向脱位力能够满足临床要求。
关键词 上颌中切牙；金属烤瓷反3/4冠；抗切向脱位力
INCISAL DISLOCATION STRENGTH OF ANTERIOR TEETH RESTORED WITH
METAL-CERAMIC REVERSE THREE-QUARTER CROWNS: AN IN VITRO STUDY
Ding Nongle, et al
Department of Prosthodontics,the Dental Hospital of Luzhou medical
college
Abstract Objective: To investigate the incisal
dislocation strength of maxillary central incisors restored
with metal-ceramic reverse three-quarter crowns. Methods: Twenty
noncarious human maxillary central incisors were prepared for
three-quarter crowns. Three-quarter crowns were fabricated according
to laboratory procedure. All restorations were placed to abutments
respectively.Tensile strength was tested with a universal testing
machine at crosshead speed of 2mm per minute paralleling the
long axis of the tooth. Tensile sterngth was automatically recorded
by the testing machine. Then twenty teeth were prepared for
metal-ceramic reverse three-quarter crowns(the metal coping
of metal-ceramic reverse three-quarter crowns were fabricated
according laboratory procedure. All restorations were placed
to abutments respectively. tensile strength was tested with
a universal testing machine at crosshead speed of 2mm per minute
paralleling the long axis of the tooth).And after the same procedure,the
tensile sterngth was automatically recorded. Means were calculated
and analyzed with paired-samples T test by the SPSS14.0 software
package. Results: The means of tensile strength were : three-quarter
crowns, 0.54 0.487N; metal-ceramic reverse three-quarter crowns,
2.96 1.58N. There was significant difference(P＝0.01).Conclusion:
The incisal dislocation strength of metal-ceramic reverse three-quarter
crowns can achieve clinical requisition.
Key words Maxillary central incisors；Metal-ceramic
reverse three-quarter crowns；Dislocation strength
