DENTAL FORMULA

DENTAL FORMULA

•  This is numerical representation of teeth on upper half & lower half of the jaws
• If total number of teeth of a formula is multiplied by two ,it will give total number of teeth
• In  mammals ,there is fixed number of teeth characteristics of each species
• The maximum number of teeth in placental mammals with heterodont dentition is 44 e.g; horses & pigs
• A natural space between two types of teeth id referred to as a diastema
• In Rabbit which lacks canine teeth, a diastema is present between the incisor & premolar one each side
• In cat , there is a diastema between the canine and first premolar on each side of the lower jaw
• In many carnivore mammals such as dog ,last upper premolar and first lower molar teeth (carnassial teeth) are specially large and used for shearing the flesh
• Premolar is the biscuspid of dentist with two cusps and bifurcated roots
• Molar is polycuspid with many roots
• Both premolars and molars are known as “Cheek teeth ” or grinding teeth
• Tusk of elephant is an enormously enlarged upper incisor tooth and grows continuously throughout life.
• Tusk of walnus are modified canines
• The gnawing chisel-like incisor of rabbit or rat have also open pulp cavity and grow continuously
• Teeth are absent in toads of the genera bufo  and Pipa .
• Teeth are lacking in chelonia (reptiles )and modern birds.
• Fangs are certain specialized teeth attach to maxillary bones in poisionous snakes
• Fangs are long , curved ,Sharp & pointed . they serve as hypodermic needles for injecting poison into the body of the victim
• When a functional fang is long or damaged , it is replaced by one of the reserve fang