LECTURE 8 teeth Flashcards
function of teeth
ingestion and mechanical breakdown of food
2 sets of teeth/dentition
primary/deciduous teeth, permanent teeth
types of permanent teeth
incisors (rip, cut), canines (tear and pierce), premolars (grinding), molars (grinding)
articulations of teeth
mandible and maxilla, covered with gingiva (oral mucosa, gums)
type of joint of teeth
gomphosis (peg in socket with ligament), periodontal ligaments (collage fibers) anchor tooth in bony socket (continuous with gingiva, cementum attaches external surface of tooth to periodontal ligament), synarthrosis, teeth are not bone but are part of skeleton
regions of teeth
crown (projects into oral cavity), neck (gumline), root (beyond neck in alveolus of bone)
description of enamel of teeth
covers crown of tooth, avascular and acellular (calcium salts), hardest substance in body (harder than bone, not renewed or replaced)
description of dentin of teeth
deep to enamel forming bulk of tooth, made of minerals and collagen, harder than bone but softer than enamel, maintained during life
description of pulp cavity of teeth
center of tooth, loose CT with vessels and nerves, supplies nutrients to hard tissues
description of root canal of teeth
portion of pulp cavity in the root
description of apical foramina of teeth
opening into the root canal at the tip of each root for blood vessels and nerves
blood supply to teeth
superior/inferior alveolar artery, branches of external carotid artery
innervation of teeth
trigeminal nerve V, maxilla: superior alveolar nerves, mandible: inferior alveolar nerves
teeth at birth
no teeth are erupted (developing in mandible/maxillae), jaw covered by gingiva
teeth at 6 months
lower central incisors first to appear, 20 deciduous teeth by age 2, no premolars
deciduous dental formula
2I, 1C, 2M/2I, IC, 2M x 2 = 20 teeth
teeth in adolescence to adulthood
permanent teeth enlarge and develop, roots of deciduous teeth reabsorbed, teeth loosen and fall out, begin to erupt from 7-13 years of age, third molars (wisdom teeth) emerge from 17-25 years (may be absent)
adult dental formula
2I, IC, 2P, 3M/2I, IC, 2P, 3M x 2 = 32 teeth
description of cavities of teeth
caries, demineralization of enamel by bacteria, in severe cases erodes dentin of tooth, most sever cases erosion penetrates pulp cavity
description of gingivitis
inflammation of the gingiva cause by plaque accumulation, leads to periodontitis
description of periodontitis
infection of periodontal ligament leading to its destruction along with the bone around the teeth
