Cystic fibrosis (CF) is an autosomal recessive disorder occurring in one of every 2000 births. It is the most common genetic disorder affecting whites. The genetically altered protein affects exocrine gland function which leads to micro obstruction of the pancreas, which results in cystic degeneration of the pancreas and ultimately a digestive enzyme deficiency producing malabsorption of nutrients. These children have increased chest diameter, clubbing of fingers and toes, chronic productive cough, decreased exercise tolerance. Cystic fibrosis related diabetes is more common with high incidence of tooth discoloration, low incidence of dental caries, high incidence of mouth breathing and open bite malocclusion associated with chronic nasal and sinus obstruction. It should be preferred to treat in a more upright position to allow them to clear secretions more easily. Extractions can be carried out under local anesthesia. Use of sedative agents that interfere with pulmonary function should be avoided. Along with possible etiological factors, clinical features, diagnosis, tests for CF and treatment options for discoloration of the teeth are discussed.