BackgroundOrthodontic tooth movement (OTM) is based on induction of periodontal tissue remodeling. Mechanical tooth stimulation results in the release of pro-inflammatory mediators. These mediators cause bone resorption and deposition at the pressure and tension sites and play a role in OTM. Thus, assessment of chemical biomarkers can help determine the exact amount of load and its duration of application required for each tooth and select the most efficient treatment plan with minimal complications.ObjectiveThis study aimed to determine the level of tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6) in gingival crevicular fluid (GCF) during OTM.MethodsThis randomized split-mouth clinical trial (parallel) was performed on 10 patients who were presenting to the Orthodontic Department of Qazvin University of Medical Sciences from November 2015 to June 2016. A canine tooth was randomly selected as the study group and subjected to distalization force while the contralateral canine tooth served as control. Using paper strip, GCF was collected from the study and control teeth prior to orthodontic force application (T0), one hour after (T1) and 28 days after force application (T2), then the level of TNFα and IL-6 was measured using ELISA. Data were analyzed using SPSS version 20 via Friedman and Wilcoxon test, and considering the significance level at p<0.05.ResultsThe level of TNFα (p=0.0799) and IL-6 (p=0.678) at both sides of study teeth was higher than both side of control teeth at T1. Also, the level of IL-6 (p=0.515) and TNFα (p=0.508) were higher at the tension side compared to the pressure side; but the difference was not statistically significant.ConclusionDue to the free circulation of GCF in gingival sulcus, the level of mediators in the GCF collected from the mesial and distal areas alone cannot serve as a suitable index for assessment of activity at the tension and pressure sites.Trial registrationThe trial was registered at the Iranian Registry of Clinical Trials with the IRCT ID: IRCT2017030632903N2.FundingThe present study was supported by a grant from the Research Council, Qazvin University of Medical Sciences, Qazvin, Iran (thesis no.: 40).

Objective: The purpose of this study was to identify which diagnostic parameters related to impacted maxillary canines can be reliably detected by the conventional orthodontic radiographic modalities and which factors need to be assessed by cone-beam computed tomography (CBCT). Design: In this cross-sectional study, 8 orthodontists evaluated 7 parameters related to the position and anatomy of the impacted canines by means of 2-dimensional (2D) records. After 1 month, the same process was repeated by means of CBCT by the same clinicians. Setting: Qazvin University of Medical Sciences. Patients and Participants: Thirty-two patients with alveolar cleft and impacted maxillary canines who had CBCT scans, lateral cephalograms, and orthopantomographs as pretreatment records. Main Outcome Measure: The diagnostic accuracy of 2D and 3-dimensional (3D) radiographic modalities was compared with each other and also with the gold standard by 3 radiologists. Results: The diagnostic accuracy of 2D and 3D imaging modalities was not significantly different regarding the mesiodistal inclination of the impacted tooth ( P = .09), apex anatomy ( P = .10), and mesiodistal position of the apex ( P = .19). Cone-beam computed tomography had significantly higher diagnostic accuracy than conventional radiographic modalities regarding overlapping the adjacent tooth ( P = .001), labio–palatal and apico–coronal position of the crown tip, and root resorption of the adjacent tooth ( P = .01). Conclusion: The conventional orthodontic radiographic modalities were as accurate as CBCT for determination of impacted canine inclination, apex anatomy, and mesiodistal position of the apex. Cone-beam computed tomography showed higher diagnostic accuracy for other parameters.