Oral Thrush (Candidiasis): This is a common condition in newborns, especially in the first few weeks of life. The presence of white bumps without redness or pain is highly suggestive of oral thrush, which is caused by an overgrowth of Candida fungus. It's often seen in the oral cavity, including the tongue and lips.

Milk Pustules or Milk Blisters: These are small, benign bumps that can appear on the tongue or lips of newborns, often associated with breastfeeding. They are thought to be caused by the blockage of minor salivary glands.
Fordyce Spots: These are small, white or yellowish bumps on the lips, inside of the cheeks, and sometimes on the tongue. They are caused by the abnormal presence of sebaceous glands in the mucous membranes and are generally harmless.
Traumatic Irritation: Minor trauma, such as from sucking or feeding, can cause small, white bumps on the tongue or lips.

Congenital Syphilis: Although less common, congenital syphilis can cause a variety of oral manifestations, including mucous patches or snail track ulcers, which might initially appear as white bumps. Given the potential severity of untreated syphilis, it's crucial to consider this diagnosis.
Herpes Simplex Virus (HSV) Infection: Neonatal HSV can present with oral lesions, although these are typically painful and may be accompanied by other systemic symptoms. The absence of pain and redness makes this less likely, but it's a critical diagnosis not to miss due to its potential severity.

White Sponge Nevus: A rare, benign condition that affects the mucous membranes, causing white, spongy lesions. It's usually present at birth or appears during early childhood.
Leukoedema: A condition characterized by a white, opaque appearance of the buccal and labial mucosa, which can sometimes be mistaken for white bumps. It's more common in older children and adults but can be considered in the differential diagnosis of oral white lesions in newborns.