Oral regurgitation after reflux provoking meals: a possible cause of dental erosion?

Certain foods and drinks such as alcohol, heavily spiced or fatty meals are known to provoke gastro-oesophageal reflux (GOR). This may give rise to symptoms of heartburn, epigastric pain and occasionally oral regurgitation of the gastric contents. Oral regurgitation of gastric juice is important in dentistry because of its association with dental erosion. This study measured oesophageal and oral reflux in 12 healthy subjects after a curry meal taken with alcohol 2 h before sleep. Each subject repeated the test with a bland non-reflux provoking control meal. GOR was measured by recording distal and proximal oesophageal pH on a dual channel, portable pH monitor. Oral pH was measured with a pH sensitive radio-telemetry capsule (RTC) held on the palate in a vacuum formed splint. Signals from the RTC were received by an aerial worn around the head. The pH change produced by GOR was estimated as the percentage time that pH (PTpH) was less than 4 in the distal oesophagus. Similarly, the PTpH was estimated < 4 and < 5 in the proximal oesophagus and < 5.5 and < 6 in the mouth over a period of 16 h. All subjects tolerated the monitors overnight with little loss of data and data were collected from all studies. The curry meal provoked GOR in all subjects, but only in six subjects to pathological levels according to international guidelines. The results show that GOR measured as the PTpH < 4 was significantly higher in the distal oesophagus whilst subjects were supine after the curry meal than with the control meal (P = 0.0006) and in the proximal oesophagus in the upright position (P = 0.006). There was a significant difference in the oral PTpH < 5.5 between the two meals for the total study period (P = 0.005). The bland meal provoked pathological levels of reflux in only two subjects. In one of these subjects the bland meal provoked oral regurgitation with a PTpH < 5.5 of 13.5%. In the remaining subjects little oral regurgitation occurred.