[A clinical observation of epithelial pearls in newborn babies. 1. Appearances and continuous changes]

The purpose of this study was to learn about the appearances and continuous changes of epithelial pearls. The study group comprised 517 normal newborn babies (261 males and 256 females) aged from 24 hours of birth to 22 days. Furthermore, we made the follow-up survey on the continuous changes in 21 newborn babies at the Niigata University Medical Hospital. The following results were obtained by analyses of the examination of the oral cavity in newborn babies during the period from December 1987 to December 1988. 1) Yellow-white in colour, pinhead shaped, 1-3 mm diameter in size, elevated firm nodules were seen in the alveolar ridge mucosa of the maxilla, mandible and/or palate. The average number of epithelial pearls was 1-3. 2) The number of newborn babies who had epithelial pearls was 226 (109 males and 117 females) out of 517 (43.7%). There was no predominant sex preference. 3) The most common location was the maxillary alveolar mucosa (309, 72.5%) followed by the median palatine raphe (97, 22.8%) and mandibular alveolar mucosa (20, 4.7%). 4) In this study, the relationship between the environmental factors of newborn babies in the prenatal and postnatal periods (mother's age, the course of the pregnancy, trouble at birth, the period of pregnancy, baby weight at birth etc.) and the rate of appearances of the epithelial pearls was examined. These factors showed no significant relationships. 5) Based on the findings of the clinical investigation of epithelial pearls during neonatal period, some cases were found and involved thickening and/or thinning in changes in the quantity and number.