Masseter is the main breastfeeding muscle of mastication and has help from the Mentalis muscle to evert lower lip (quick look slide 55).

Buccinator and orbicularis oris are muscles of facial expression mainly used by the bottle fed and those sucking on pacifiers and other decoys


  • Dampening and early extinguishing of the evolutionary safety of the tongue extrusion reflex in the bottle-fed
  • Undoing of evolutionary advantage leading to premature introduction of solids
  • Unphysiological sucking, chewing, swallowing, palate formation,
    cranio-facial growth and speech (quick look slide 55)
  • Malocclusions and sleep disordered breathing

Ashley Montagu Breastfeeding and Food Policy in a Hungry World Ed. Dana Raphael pp 192 ISBN 0-12-5809506

Catherine Watson Genna, Supporting sucking skills, 2nd ed., chapter 1, ISBN 978-1-4496-4736-0

Early Human Development  1995;42:185-193  Inoue N  et al

Safe solids as early as six months