Dorelia Lucia Cãlin et al. 364 Vol. XI  Nr. 3  2012 CLINICAL ANATOMY Revista Românã de Anatomie funcþionalã ºi clinicã, macro- ºi microscopicã ºi de Antropologie DENTAL EROSION AND OTHER ORAL ANATOMICAL CHANGES CAUSED GASTROESOPHAGEAL REFLUX Dorelia Lucia Cãlin 1 , Mihaela Mitrea 2 , L.L. Frâncu 2 Gr. T. Popa University of Medicine and Pharmacy, Iaºi 1. Discipline of Cariology and Restorative Odontotherapy 2. Discipline of Anatomy DENTAL EROSION AND OTHER ORAL ANATOMICAL CHANGES CAUSED GASTROESO- PHAGEAL REFLUX (Abstract): Gastroesophageal reflux can cause oral pathological changes. Dental erosion is the predominant oral manifestation of the disease and allows the dentist to make the initial diagnosis. Undiagnosed erosion can cause devastating damage to the dentition over time. Patients were not aware of the underlying condition. The causes of erosion are difficult to define without a detailed history. Erosive lesions were present in various degrees in the same patient, maxillary teeth showing greater erosive lesions in comparison with the lower teeth. Dentists must be familiar with typical and atypical symptoms of the disease because they could be the first to suspect the presence of the disease by observing dental erosion that cannot be explained. The consequences of  intrinsic erosion are often severe and require a complex restorative treatment to restore tooth tissue loss. Key words: GASTROESOPHAGEAL REFLUX, TOOTH ERO- SION, ORAL EFFECTS OF GASTROESOPHAGEAL REFLUX Dental erosion or, more correctly, corro- sion is defined as an irreversible loss of hard tissues of tooth produced by chemical or elec- trolytic processes of nonbacterial origin, in contrast to carious tooth damage (1, 2). Dental erosion is caused by the presence of acid of non-bacterial origin in the mouth. Tooth enamel begins to dissolve at a pH of 5.5 (3). Hydrochloric acid in gastric juice pro- duced by parietal cells of the stomach, has a very low pH, less than 2 and therefore, it can cause significant chemical erosion (4). Dental erosion is caused by the presence of acids in the oral cavity that may be of intrinsic (endogenous), extrinsic (exogenous) origin or a combination them (5). The term intrinsic erosion implies the pres- ence of gastric acid in the oral cavity (6). Intrin- sic sources of acid include chronic vomiting, persistent acid regurgitation, gastroesophageal reflux, rumination (7). Acid reflux is defined as abnormal propul- sion of stomach contents into the esophagus. Reflux occurs when the lower esophageal sphincter, which controls the flow of food and fluids between the stomach and esophagus, does not work properly. This sphincter is a ring- -shaped muscle, being the anatomical location of the gastroesophageal junction, and behaves like a valve allowing normal passage of food and liquids only in one direction: from the esophagus to the stomach. Gastroesophageal reflux disease occurs when the lower esophageal sphincter relaxation oc- curs at the wrong time (the other time than the ingestion of food) and remains open for a long time. Normally the sphincter opens for a few seconds during swallowing. Sphincter relaxa- tion produces decrease in pressure gradient between it and the stomach. The stomach con- tent comes into contact with the cervical eso- phagus, pharynx and oral cavity. The etiology of gastroesophageal reflux. The main factors that cause weakness or re- laxation of lower esophageal sphincter are:  Lifestyle: alcohol consumption, smoking, obesity,  Medication: beta-blockers, calcium chan-