Background. Orthodontic treatment with fixed mechanotherapy using appliances and permanent retain ers bonded after treatment is a routine procedure performed in clinical dentistry. Patients with braces or retainers sometimes need to undergo magnetic resonance imaging (MRI) for various reasons. Radiologists do not know the exact impact of the materials used in orthodontics on the diagnostic image quality of MRI scans.Objectives. The aim of the study was to evaluate the influence of different types of orthodontic brackets and permanent retainers on the diagnostic image quality of MRI scans. Material and methods.Twenty patients with bonded brackets (stainless steel buccal/labial, stainless steel lingual, ceramic selfligating with metal slots, ceramic, and polycarbonate) and 18 patients with bonded fixed retainers (titanium, fiberreinforced composite, multistranded stainless steel, and different combinations of permanent retainers) participated in the study. The same adhesive was used for bonding. Cranial MRI scans of 6 regions were acquired for each subject, using a 1.5T MAGNETOM machine. Six radio logists evaluated the images and provided scores based on the modified receiver operating characteristic (ROC) analysis of distortion. The paired Wilcoxon signedrank test was used to assess differences between the materials and the anatomic sites with regard to the distortion rating scale. Cohen's kappa coefficient (κ) was applied to establish the interrater reliability. Results.A statistically significant difference was found between stainless steel brackets (both buccal/ labial and lingual) and all other experimental materials in terms of mean distortion scores (p = 0.020 or p = 0.024). The interrater reliability proved to be high. Conclusions.Stainless steel buccal/labial and lingual brackets caused maximum distortion of the images, which became nondiagnostic; hence, such brackets should be removed before MRI. Ceramic and polycarbonate brackets as well as fiberreinforced composite retainers did not distort the images; thus, they need not be removed. Ceramic selfligating brackets with metal slots, titanium retainers, multistranded stainless steel retainers, and combinations of fixed retainers caused minimal distortion; however, the images were still diagnostic. Hence, patients using these materials may not need to have them removed before MRI.

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Agenesis is a rare abnormality of paramesonephric ducts, which result in complete absence of uterus and fallopian tubes. In this article, cases of absent development of Mullerian ducts are presented, followed by a brief discussion of etiology, clinical presentation, diagnosis and management of the patient in Mullerian agenesis. Differential diagnosis in a patient presenting with primary amenorrhoea and normal external genitalia is discussed.