Clinical Research About Factors Associated With Cracked Teeth And The Extent Of The Crack

Objectives1. The objective of this study was to analyze the factors associated with cracked teeth through a questionnaire about the possible influencing factors of cracked teeth, and to provide reference for the prevention of cracked teeth.2. Comparing the difference between the cone-beam CT and periapical radiography in the diagnostic aspects of cracked teeth. By measuring the length, width of occlusal crack and length of the vertical surface crack, observe the extent of the crack after opening the pulp, and do the relevant analysis of these.Methods 1. According to the diagnostic criteria of cracked teeth, collecting35 patients as the case group in Department of Endodontics of Tianjin Medical University Dental Hospital, a 1: 2 pairing method matched case-control study, selecting 70 cases non-cracked teeth patients as a control group. Fill out the questionnaire of cracked teeth.Questionnaire should include: basic patient information, medical history, past history, history of systemic disease, if there is bruxism, quench eating habits, joint disease, clenching habits, unilateral chewing habit, the habit of knocking teeth, like to eat rough tough food and other habits. Clinical checklist including: pulp vitality test temperature, percussion, palpation, biting clinic, loosening of teeth, if there is an implicit direction cracks and hidden cracks.2. March 2014-December 2015 period, collecting 22 teeth as the case group in Department of Oral and Maxillofacial Surgery of Tianjin Medical University Dental Hospital,, under a microscope and make a clear diagnosis.The cone beam CT and X-ray be imaged, and save the image data in the database backup.Measuring the length, width of occlusal crack and length of the vertical surface crack, after Micro-CT scanning.Opening the pulp under the microscope, and exposed pulp chamber to observe and observe the extent of the crack.Application of statistical methods to compare differences between PR and CBCT in the diagnosis of cracked teeth diseases; the correlation analysis of the the length, width of occlusal crack and length of the vertical surface crack; using ROC curves to assess the diagnostic value of the length, width of occlusal crack in whether the crack extends to the root.Results 1. Whether to cracked teeth as the dependent variable, bruxism, quench eating habits, unilateral chewing, like rough tough food, biting hard objects are independent variables, univariate conditional Logistic regression analysis, the above five indicators are questionnaire there was statistically significant(P <0.05). In more than five are independent variables, multivariate conditional Logistic regression analysis, only unilateral chewing habit, quench eating habits, likes rough tough food, biting hard objects was statistically significant(P <0.05).2. Compare the differences between PR and CBCT in the diagnosis of cracked teeth, the difference was statistically significant(P <0.001).Comparisons correlation the length, width of occlusal crack and length of the vertical surface crack, the correlation coefficients were 0.782, 0.651, were statistically significant(P <0.001).The AUC of length of occlusal crack 0.839; when the cutoff value of 3.75, the sensitivity and specificity were 0.9?0.91.The AUC of width of occlusal crack was 0.760. When the cutoff value of 0.15, the s was ensitivity and specificity were 1?0.354. The the difference was statistically significant(P <0.05).Conclusions 1. Unilateral chewing habit, quench eating habits, likes rough tough food, biting hard objects, four factors were independent risk factors for cracked teeth occurred.2. The length, width of occlusal crack can be a diagnostic value in predictive whether the crack extends to the root.3. CBCT is better than periapical radiographs in aspect of cracked teeth diagnosis.