A FOCUS ON FEEDING, CHEWING AND TEETHING

BY DAVID A. TESINI DMD, MS, FDS RCSEd

Feeding and chewing behaviors are important conditioners for proper development of the face and jaws. The progression of oro-facial development from infancy through childhood affects the skills of chewing, drinking, swallowing, speech and breathing.

Eruption of the teeth occur in a specific progression and timed sequence consistent with food progressions from liquids to pureed to solids. For Children with Special Health Care Needs (CSHCN), development of the necessary skills are often burdened by sensory and tactile delays. It is important to know that over-the-counter products can be both helpful and harmful. This article will give you that general understanding of the related science and practical knowledge needed to advocate for your child's needs.

A LITTLE SCIENCE TO GET US STARTED

Human feeding is dependent on an integrated sequence of events requiring the coordination of over 20 muscles to move food and saliva in the mouth, from the first chew to the swallow. Children's oral motor development begins with the mouth working as a total unit, but as the child matures, the movement of jaws, the tongue and lips function as separate but coordinated entities. There is a progression over time with corresponding development of the jaw joint (TMJ) which adds jaw stability needed to chew foods varying in firmness, size and texture. More recent research added to the understanding that early perceptual and discriminatory abilities also develop between infancy and early toddlerhood.

ONCE BITTEN: Learning to bite and chew food is challenging for Children with Special Health Care Needs, and most difficult for those with sensory integration type disorders.

It has been demonstrated that the oro-motor developmental stages of the child jaw movement, masticatory muscle functions, (i.e., feeding functions, tongue functions and eruption of the teeth) has an influence on what textures are accepted or rejected. Simply put, the child knows what types of food she can eat and what types she cannot. Infants start out with only liquids and at four to six months, the diet is complemented with the first solid foods, which are semi-liquid (e.g., pureed fruits or vegetables). At around six months, teeth will develop and the lateral/more advanced movement of chewing begins. By this stage, infants have experienced different textures and learn to like textures that can be easily manipulated by their tongue, lips and gums. These preferences are determined by their prior experience with texture variations.

In fact, over the first two years of a child's life, the most marked period of increasing oral skill occurs between the age of six and 10 months for transition to more solid textures. Further increases in chewing efficiency continue up to 24-36 months. This corresponds directly with the "teething stage" (the eruption of teeth and the downward and forward growth of the mandible). The chronological link between chewing and teething thereby has been established.

What the science teaches us is that, as the child matures, the movement of jaws, the tongue and lips function as separate, but coordinated entities. Jaw movement, masticatory muscle functions, i.e., feeding functions, tongue functions and eruption of the teeth, have an influence on what textures are accepted or rejected. The child must strengthen their muscles and coordination skills in order to progress along the feeding and speech path. During the most critical time of oral development (age 6-24 months) the child's muscles/joints/ tongue learn to handle and coordinate the eating of complex solids. This corresponds directly with the eruption of