Background: Tooth formation was recognized as useful body system to assess maturity and predict age. Tooth mineralization is much less affected by the endocrine and different nutritional status than bone mineralization, and teeth formation provides a more reliable indication of chronological age. Demirjian et al. in 1973 presented a scoring system and method for dental age estimation on a sample of French-Canadian children. Chaillet et al. and Willems et al. modified original Demirjian method. This study aimed to evaluate the accuracy of four Demirjian’s, Chaillet and Willems methods for age estimation in the children of Kosovo. Materials and methods: The cross-sectional study was based on the evaluation of the sample of 1022 orthopantomograms (OPTs) of healthy Kosovar children, aged between 5 and 14 years. OPTs were taken from the Radiology unit of University Dentistry Clinical Center of Kosova, as part of random clinical treatment. We tested the accuracy of four methods based on seven mandibular teeth, Demirjian from 1973 (Dem73) and 1976 (Dem76), Chaillet from 2005 (Chaillet) and Willems from 2001 (Willems) and two Demirjian’s methods based on different sets of four teeth (Dem76PM1 and Dem76IN2). Results: For most tested methods, we found statistically significant differences between the chronological age (CA) and dental age (DA) (p < 0.05). In males, the most accurate method were those using four teeth, Dem76IN2 (0.03 years) following by Dem76PM1 (−0.05 years), following those using seven teeth, Willems (−0.14 years), Chaillet (−0.24 years) and Dem73 (0.43 years). In females, dental age was the most accurate for the Willems method (−0.24 years) following Chaillet (−0.35 years), Dem76 (0.43 years) and Dem73 (0.55 years), while Dem76PM1 and Dem76IN2 overestimated by 0.45 years and 0.46 years, respectively. The mean absolute difference between DA and CA were between 0.61 years for the Willems, to 0.78 years for the Dem73 in males, and 0.64 years for the Willems to 0.75 years for the Dem76IN2 in females. Conclusion: The Willems method was the most accurate for estimating a dental age if all seven mandibular teeth are available for analysis, and we found the similar accuracy of Dem76PM1 and Dem76IN2 methods. Therefore, we may encourage their use for age estimation on the Kosovar children.