routine orthodontic procedure in Dhulikhel Hospital, Kathmandu University School of Medical Sciences are collected for the study. The tooth immediately after extraction is rinsed with water to clean the blood debris then dipped into 5.2% Sodium Hypochlorite solution for two minutes and stored in 10% formalin until measurements are done. While collecting the teeth, male and female teeth are collected in a separate collection bottles with clearly written labels. Verbal consent is obtained from patient to keep their extracted teeth in hospital. In case the patients who wanted to take their extracted teeth with them, the teeth were given. Teeth with fractured and incompletely formed roots, with open apex and gross malformation are excluded from the study. The root forms were identified as single root, double root, triple root and fused root; described originally by Turner [13] later by Loh [9]. The root and tooth length are measured from mid buccal cemento-enamel junction and tip of buccal cusp to the root apex respectively with the help of a digital caliper (MC 01010157, 150 mm, China). In case of double and triple rooted teeth, the measurement is taken up to the apex of the longest root. Descriptive analysis was done for the root from, tooth and root length. Root length and tooth length were compared between male and female samples by independent t-test. The p-value was kept 0.05 for the level of significance. ResultsThe frequency distribution of the root from, tooth and root length Keywords: Maxillary first premolar; Root form; Root length; Tooth length IntroductionOrthodontic treatment is usually associated with dental extraction and maxillary first premolar teeth are most commonly extracted teeth for this purpose [1][2][3][4][5]. Maxillary premolars are also commonly affected by dental caries which necessitates the need of root canal treatment. These teeth are found to have numerous variations in root form as well as root canal system which is of importance for general dentists as well as endodontists. First premolars being located in between anterior and posterior segment, they resemble with canine and molars in form as well as function [6]. On labial view, maxillary first premolars resemble more closely with maxillary canines where as they resemble the function of molar mostly i.e., grinding and chewing food. In absence of molars, premolars do the function of chewing food particles. However they are also used for tearing the food which is primarily the function of canines. Maxillary first premolars are usually thought to have two roots. However there are numerous racial differences on the root form, number of root and root canal system [7][8][9][10]. Extraction of maxillary first premolar might be difficult, especially when it has two separate roots. In orthodontic practice, therapeutic extraction of these teeth should be performed cautiously. When there is fracture of roots, extreme precaution should be taken to preserve the buccal cortical plate. If prior information about the number and curvature of root i...