8.4  Oral habits.

Oral habits

Keypoints:

1.Oral habits

A.Thumb and finger habits: openbite;

B.Tongue thrust (tongue anterior positioning):openbite, bimaxilla protrusion; proclined anterior teeth; anterior crossbite;

C. Lip habits: anterior deepbite; proclined anterior upper teeth; retruded mandible; anterior crossbite;

D.Month breathing: narrowed arches; protruded maxilla; retruded mandible;incompentent lips;

E.Bruxism: primary and permanent teeth worn; deep overbite;

F. Unilateral mastication: imbalance development of jaws.

2.The functional factors which can cause bad oral habits:

            A. masticatory function

         B. habits

         C.tongue thrust

         D. respiratory function

3.Equilibrium theory

4.Digit sucking 

         A kind of bad oral habit during which the tongue is lowered and the cheeks contract during sucking , the pressure balance against the upper teeth is altered, and the upper but not the lower molars are displaced lingually;

A.Digit sucking beyond the time that the permanent teeth begin to erupt (7 years of age) can lead to malocclusion:

    ●Flared and spaced maxillary incisors;

    ●Lingually positioned lower incisors;

    ●Anterior open bite;

    ●Narrow upper arch:

B.Greater effect on dental development

    ●Features

        ●Narrow V shaped maxillary arch

        ●Anterior open bite

        ●Retroclined lower incisors

        ●Buccal crossbite

5.Tongue thrust.

        Clinically, tongue thrust is defined as a forward placement of the tip of tongue, usually happens in the mixed dentition period, which causes openbite and tooth labially/buccally tipping. Tongue thrust needs to be treated in time.

●Infantile swallowing pattern:

       ●Active contractions of the musculature of the lips

       ●A tongue tip brought forward into contact with lower lip

       ●Little activity of the posterior tongue or pharyngeal musculature

●Adult swallowing pattern:

       ●No contracting the muscles

       ●Teeth are momentarily in contact

       ●Tongue remains inside the mouth

6.month breathing habits and respiratory problems

       ●Incompetent lips;

       ●Priclination of maxillary incisors;

       ●High and narrow palatal vault;

       ●Narrowed dental arches;

       ●Mandibular clockwise rotation:

       ●Skeletal class II, long face syndrome;

        Mouth breathing: Change in posture that secondarily altered long-duration pressures from the soft tissues.

7.Bruxism: Teeth grinding while sleeping;

  ●Causes:

       ●Occlusal interference

       ●Psychological factors;

       ●Sleep posture;

  ●Intervention:

       ●Occlusal adjustment;

       ●Psychological therapy;

       ●Tooth weatriness prevention;

       ●Others:

               ●Sleep posture adjustment;

               ●Masticatory muscle tense release: massage;

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Homework（please send your answer to email）：

Please illustrate your understanding of the clinic specialties of Pediatric Dentistry.