The control group included 20 subjects who had not started treatment yet and demonstrated no radiographic evidence for root shortening. test were utilized for statistical analysis. Results SDS-PAGE analysis identified proteins at 77, 66, 55, 50 and 26 kDa. Immunoblotting did not show any differential expression pattern between control and study groups. ELISA results revealed a significant difference in the concentrations of DMP1, PP and DSP between control and root resorption groups. Concentration of PP and DSP in severe root resorption group was also statistically higher than in moderate root resorption group. Conclusion DSP and PP could be suitable biological markers for monitoring root Rabbit Polyclonal to MYB-A resorption during orthodontic treatment, since a significant difference in the level of these dentin specific proteins is usually detected in all groups. Introduction External apical root resorption is usually a common and undesirable sequela of orthodontic treatment. 1 Generally root resorption may be described as moderate, moderate and severe. 2 Usually it is moderate and clinically insignificant; however it can occur in large amounts, i.e. loss of over one third of the root length, in some patients. Close radiographic examination of orthodontically treated individuals show some loss of Oligomycin root length in nearly every patient.3,4 The incisors are the most susceptible while the molars seem to be the least affected.5 Early detection of root resorption during orthodontic treatment is essential for identifying teeth at risk of severe resorption.6 At present, detection of root resorption is obtained using radiographic techniques. However, radiographs are technique sensitive and can detect resorption only after 60-70% of the mineralized tissue is lost and they only provide two-dimensional information primarily identifying apical change. In addition, radiographs cannot show if the process of root resorption is still active. Monitoring the progress of root resorption requires additional radiation exposure to the patient. The initial resorption lacunae are small and can be identified only by histological methods. Orthodontically-induced root resorption areas after 7 weeks of treatment, verified histologically, are not visible in periapical radiographs.7 Thus, using film-based radiography, the diagnosis is uncertain during the first months of treatment. After 5-6 months a reliable radiographic diagnosis of apical root resorption can be performed.8 Published results demonstrate the presence of DMP1 and PP in the GCF of patients undergoing orthodontic treatment.9 The purpose of this study is to determine if an alternate molecular method is effective in assessing ongoing resorption in active orthodontic patients by identifying and quantifying extracellular matrix proteins associated with dentin mineralization like dentin matrix protein 1 (DMP1), dentin phosphophoryn (PP) and dentin sialoprotein (DSP) in the gingival crevicular fluid (GCF) of subjects undergoing orthodontic treatment. PP and DSP are non-collagenous dentin-specific matrix proteins postulated to be involved in the mineralization of pre-dentin into dentin10-13, while DMP1 is present in dentin as well as in bone.14, 15 Dentin undergoes continuous deposition throughout life as a secondary dentin only around the pulpal surface. Therefore, these proteins are not routinely released into the surrounding space as dentin does not undergo the process of remodeling as in bone. It is only in the presence of active external root resorption that these proteins could be freed into the periodontal ligament space. Therefore, we hypothesize that a significant qualitative and quantitative difference of levels of these proteins exists between orthodontic Oligomycin patients with radiographic indicators of root resorption and non-treated patients and between patients with moderate and severe root resorption. Materials and methods Subject selection Sixty subjects were selected from Oligomycin patients seeking treatment in the Department of Orthodontics at the Oligomycin University or college of Illinois at Chicago. Two study groups and one control group were set up. One study group included 20 subjects in treatment for at least one year and with radiographic indicators of moderate root resorption, less than 2 mm (1.34 0.39 mm) of root loss (Fig. 1a).