Segmenting teeth in dental X-ray images has been pursuit for many years, mainly relying in unsupervised methods. Although many approaches were proposed and tested, successful results were still far from being reached. Segmenting tooth in buccal images are mandatory for more complex tasks in decision support systems. This is the first step to detect not only teeth and their constituent parts, but also artifacts (e.g., prosthesis), tooth problems, and even missing teeth.