Some transient benign oral mucosal conditions are often observed in newborns. These lesions exhibit a wide range of developmental abnormalities and morphologic variations. The identification and differentiation of the lesions remain crucial to guide clinicians in prioritizing the management of these problems as well as in the education to anxious parents.
In 1880, a Prague pediatrician Alois Epstein first described Epstein disease as the presence of small nodules in the oral cavity of newborns.
Multiple investigators reported a high rate of occurrence of palatal mucosal cysts in fetuses and infants. However, it was not until 1967 when Alfred Fromm studied and classified them according to their location and composition as Epstein pearls, Bohn nodules, and dental lamina cysts based on his comprehensive study of 1367 newborn infants. This was one of the first and largest studies done on oral cysts. Fromm concluded that these lesions were commonly found among infants and there were distinct types based on their histology and clinical presentation.
Some authors use these terms interchangeably. Epstein pearls have been labeled as epithelial debris of the tooth follicle, gingival glands of Serres, and as abortive enamel organs on the Palatine area. On the other hand, Bohn’s nodules are those found along the buccal and lingual aspects of the dental ridges. Dental lamina cysts are usually found on the crest of the alveolar mucosa. Currently, Palatal cysts of the newborn are the preferred term instead of Epstein’s pearls, Bohn’s nodules, or gingival cysts.
Keratin entrapment within the soft and hard palates causes Epstein pearls.
Epstein pearls are observed in nearly 60% to 85% of newborn infants. Among the different racial groups, Japanese newborns are most commonly affected (up to 92%), followed by Caucasians and African-Americans. No gender predilection has been observed through the years.
In one study, Epstein pearls were more common in infants born to multigravida mothers, also with those with higher birth weight. One study done in Turkey found that Epstein's pearls were less frequent in post-term babies in comparison with pre-term and term ones. A greater rate seen in term babies was reported. (Moosavi et al.).
Near the end of the 8 weeks in utero, the palate begins its development. Each maxillary process generates a lateral palatine process within the mouth. These processes are horizontal and shelf like, growing from the lateral aspect of the mouth toward the midline and downward. Between the 10 to the 11 weeks in utero, the lateral palatine processes meet and fuse with each side and with the much smaller premaxillary process and the nasal septum; palatal fusions normally are completed by the end of the 4 months of gestation.
In this stage, there is a theory that states that epithelium entrapped between the palatal shelves and the nasal process formed cysts called Epstein pearls. Another theory expressed that these cysts may come from epithelial remnants that have arisen from the formation of the minor salivary glands of the palate.
Epstein pearls are keratin-filled cysts with stratified squamous epithelium lining. Located on the mid-palatal raphe at the junction of the hard and soft palates.
They are small, opaque whitish-yellow lesions adjacent to the mid palatine raphe with no mucous glands in it Lesions are firm in consistency, size range from less than a millimeter to several millimeters in diameter. Size does not progress over time. They can be palpated during sucking by the examiner.
Epstein pearls are a clinical diagnosis. No laboratory or imagining is needed.
No treatment or removal is required. Parental apprehension should be alleviated by reassurance.
After a lesion is found in the oral cavity, it is important to formulate a differential diagnosis since this will help lead any additional evaluation of the condition and managing the patient.
Some of the differential diagnosis for Epstein pearls include:
Most of these cysts involute or spontaneously rupture eliminating their keratin contents into the oral cavity within the first few weeks to months of postnatal life.The lesions are hardly ever seen after three months of age. However, it has been suggested that part of the cystic epithelium may remain inactive even in the adult gingiva.