Dentition Teeth of Mammals B Sc II Mrs

Dentition (Teeth) of Mammals B. Sc. II Mrs. S. M. Jaunjal Department of Zoology GKG College Kolhapur

Hard and pointed structure connected to jaw bones in buccal cavity is called teethes

Arrangement of teeth in upper and lower jaw is called Dentition

Dentition is highly specialized in mammals except

Primary function of teethes

Importance of Dentition

Differenation or shape of teeth

Homodont / isodont Ex- Whales, dolphins, porpoies and armadillos etc Function- Prevent the escape of the struggling of fishes

Heterodont

Attachment of teeth

Succession of teeth

Monophyodont moles

Examples

Kinds of teeth

Incisors teeth

Front teeth by premaxillae in upper and dentaries in lower jaws

Single rooted, monocuspid and long

Curved and Sharp Chisel like Edges Ex- Rodents Cutting, biting and

Sloth bear (incisors totally absent)

Canines

Single, occur in half of each jaw, outside the incisors, upper canine is first teeth of maxillae

Elongated, single rooted and with sharp conical monocuspid crown

Piercing and tearing the flesh of prey

offence and defense

Diastema

Premolar and molar Cheek teeth / grinders

And Premolar Broad surface with ridges and tubercles

Difference

Carnassial teeth In carnivorous animals, last premolar of upper jaw and first molar of lower jaw is very sharp cups. For cracking bones and shearing tendons

Wisdom Teeth

Types

Tricodont teeth Three cones are arranged in linear series Ex- Mesozoic mammals (Extinct mammals)

Trituberculate teeth Three cones, arrange in trianges Ex- Fossil Mammals

Bunodont Crown- Rounded, small, separate tubercles for crushing Found- mammals and mixed diet animals Ex- Man, dog, pig etc

Secodont Sharp cutting edges For tearing and cutting flesh Found in carnivorous animals

Ex - Dog Last upper premolar and first lower molar are large and sharp cutting edges They bite on each other like scissors for cutting flesh Also called cranassial teeth, shearing, sectorial teeth

Selenodont teeth Crown of these teeth bears vertical crescentric cups of hard enamel Ex- Grazing animals for grinding the food Two Types

Normal teeth Lowcrowned With short tooth Ex- Ground Squrial Elongated Prism shaped High crown Low roots Ex- Grazing animals (horse and cattle)

Lophodont Intricate folding of Enamel and Dentine Cups are connected by transverse ridges called loops. Ex- elephant Single large 30 cm x 10 cm Present half of each jaw Adapted to grind all sorts of plants and grasses

Dental formula

• Number of teeths in different species, but number of teeth are constant and characteristic of same species • Number and kind of teeth I mammals represented by the formula called dental formula • It represent each type of teeth present in half of the jaw • Teeth of upper jaw paced in numerators and those of the lower jaw as denominator • Kinds of teeth are denoted by initial letters-i, c, pm and m respectively • Number of teeth present in the dental formula multiplied by the two gives total number of teeth in a species.