A common medical condition affecting the teeth is acid reflux, or gastroesophageal reflux disease GERD). Not all people actually report the feeling of reflux into the mouth. A variety of symptoms are generally reported such as hoarseness, shortness of breath, chest pain, difficulty sleeping (in many people reflux only occurs at night), coughing, or a bad taste or smells in the mouth. Studies show the adult incidence is about 7% for chronic reflux and about 36% for once a month reflux. Dentally we find also a variety of manifestations. Increased sear on the biting surfaces or along the gumline is frequently seen, especially in people that clench or grind the teeth (about 30% of adults). Also seen is dissolution of enamel on the inside of the teeth in more severe cases, generalized tooth sensitivity, yellowing and staining of the teeth, and increased incidences of decay. Patients with acid reflux may need dental care to repair the resulting erosion and decay, a nightguard to reduce future wear, and fluoride treatments. A common problem is the complete erosion of the enamel along the inside portion of the teeth requiring repair with fillings or even crowns. If all enamel is dissolved, the subsequent wear may progress quickly as only the softer dentin remains.