Logistic regression equation to screen for vertical root fractures using periapical radiographs
Abstract
Objectives: To develop a predictive equation to screen for vertical root fractures (VRFs) by numerically evaluating the shapes of radiolucent areas on the periapical radiographs of endodontically treated maxillary incisors and premolars.
Methods: 41 pre-operative periapical radiographs of maxillary incisors and premolars with radiolucent areas at root apices were used. Out of 41 teeth, 18 had a fractured root (VRF group) and 23 had a non-fractured root (non-VRF group). The periapical radiolucent area of each tooth was traced out by six examiners on a personal computer and two indices, “Complexity” and “Radial SD”, were measured. For each index, the difference between the VRF and non-VRF groups and the interexaminer differences were analysed with two-way ANOVA at 5% significance level. Multiple logistic regression analysis was used to develop a predictive equation and the probability of VRF in all samples was calculated. A receiver operating characteristic (ROC) curve was constructed to select the optimal cut-point. Each sample was predicted as “VRF” or “non-VRF” with this cut-point.
Results: For both “Complexity” and “Radial SD”, the VRF group showed significantly greater values than the non-VRF group (P<0.05). With a cut-point derived from the ROC curve, sensitivity, specificity and efficiency of VRF were 0.68, 0.80 and 0.75, respectively.
Conclusions: VRF teeth have more complicated radiolucent areas compared with non-VRF teeth. By evaluating the shapes of radiolucent areas, a logistic regression equation to screen for VRF was calculated and this equation could contribute to the diagnosis of VRF.
References
1 Meister F Jr, Lommel TJ, Gerstein H. Diagnosis and possible causes of vertical root fractures. Oral Surg Oral Med Oral Pathol 1980;49:243–253.
2 Sinai IH, Katz HR. Management of a vertical root fracture. J Endod 1978;4:316–317.
3 Vertucci FJ. Management of a vertical root fracture. J Endod 1985;11:126–131.
4 Walton RE, Michelich RJ, Smith GN. The histopathogenesis of vertical root fractures. J Endod 1984;10:48–56.
5 Lommel TJ, Meister F Jr, Gerstein H, Davies EE, Tilk MA. Alveolar bone loss associated with vertical root fractures. Oral Surg Oral Med Oral Pathol 1978;45:909–919.
6 Pitts DL, Natkin E. Diagnosis and treatment of vertical root fractures. J Endod 1983;9:338–346.
7 Tamse A, Fuss Z, Lustig J, Kaplavi J. An evaluation of endodontically treated vertically fractured teeth. J Endod 1999;7:506–508.
8 Tamse A. Iatrogenic vertical root fractures in endodontically treated teeth. Endod Dent Traumatol 1988;4:190–196.
9 Kositbowornchai S, Nuansakul R, Sikram S, Sinahawattana S, Saengmontri S. Root fracture detection: a comparison of direct digital radiography with conventional radiography. Dentomaxillofac Radiol 2001;30:106–109.
10 Culjat MO, Singh RS, Brown ER, Neurgaonkar RR, Yoon DC, White SN. Ultrasound crack detection in a simulated human tooth. Dentomaxillofac Radiol 2005;34:80–85.
11 Morfis AS. Vertical root fractures. Oral Surg Oral Med Oral Pathol 1990;69:631–635.
12 Sjögren U, Hägglund B, Sundqvist G, Wing K. Factors affecting the long-term results of endodontic treatment. J Endod 1990;16:498–504.
13 Vire DE. Failure of endodontically treated teeth: classification and evaluation. J Endod 1991;17:338–342.
14 Fuss Z, Lustig J, Tamse A. Prevalence of vertical root fractures in extracted endodontically treated teeth. Int Endod J 1999;32:283–286.
15 Gupta R, Hasselgren G. Prevalence of odontogenic sinus tracts in patients referred for endodontic therapy. J Endod 2003;29:798–800.
16 Tamse A, Zillburg I, Halpern J. Vertical root fractures in adjacent maxillary premolars: an endodontic-prosthetic perplexity. Int Endod J 1998;31:127–132.
17 Meister F Jr, Lommel TJ, Gerstein H, Bell WA. An additional clinical observation in two cases of vertical root fracture. Oral Surg Oral Med Oral Pathol 1981;52:91–96.
18 Jones DL, Irish WD, Klein GJ. Defibrillation efficacy. Comparison of defibrillation threshold versus dose-response curve determination. Circ Res 1991;69:45–51.
19 Song JH, Venkatesh SS, Conant EA, Arger PH, Sehgal CM. Comparative analysis of logistic regression and artificial neural network for computer-aided diagnosis of breast masses. Acad Radiol 2005;12:487–495.
20 Obuchowski NA. Receiver operating characteristic curves and their use in radiology. Radiology 2003;229:3–8.
21 Riddle DL, Stratford PW. Interpreting validity indexes for diagnostic tests: an illustration using the Berg balance test. Phys Ther 1999;79:939–948.
22 Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;33:159–174.
23 Agui T, Nakajima M. The basics of image engineering (6th edn).Tokyo: Shokodo, 1991. (In Japanese).
24 Signal Analytics Corporation. IPlab Spectrum user's guide. Fairfax, VA: Signal Analytics Corporation, 1989.
25 Nicopoulou-Karayianni K, Bragger U, Lang NP. Patterns of periodontal destruction associated with incomplete root fractures. Dentomaxillofac Radiol 1997;26:321–326.
26 Tamse A, Fuss Z, Lustig J, Ganor Y, Kaffe I. Radiographic features of vertically fractured, endodontically treated maxillary premolars. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88:348–352.
27 Nicopoulou-Karayianni K, Bragger U, Patrikiou A, Stassinakis A, Lang NP. Image processing for enhanced observer agreement in the evaluation of periapical bone changes. Int Endod J 2002;35:615–622.
28 Goldman M, Pearson AH, Darzenta N. Endodontic success: who's reading the radiograph? Oral Surg Oral Med Oral Pathol 1972;33:432–437.
29 Zakariasen KL, Scott DA, Jensen JR. Endodontic recall radiographs: how reliable is our interpretation of endodontic success or failure and what factors affect our reliability? Oral Surg Oral Med Oral Pathol 1984;57:343–347.
30 Reit C, Gröndahl L. Endodontic treatment decision making among a group of general practitioners. Scan J Dent Res 1988. 96:112–117.
31 Bender IB, Seltzer S Roentgenographic and direct observation of experimental lesions in bone: II. J Am Dent Assoc 1961;62:708–716.

