unit 7-dentistry

Dentistry

Only small part of tooth can be seen by handler.

Teeth grow out continuously, and so we can tell the age of a horse fairly accurately.

Horses have deciduous and permanent teeth. By five years of age all permanent teeth are in- full mouth. Molars are not present in deciduous teeth.

Teeth are classified as incisors, molars, premolars, wolf and canine teeth.

Mature males will have up to 42 teeth whereas mature females will usually have 36-38 teeth.

Canines only develop normally in male-but 2-3% mares will have upper and lower, 20-30% lower, 6-7% in upper row only.

Parrot mouth is a serious defect in the dentition of a horse whereas the upper arcade or row of teeth

protrude further out in front of the lower row.

Undershot jaw is a condition opposite that of parrot mouth.

Points- the most common problem caused by the two teeth surfaces grinding each other to a sharp point- teeth must be floated to remedy such a situation.

Shear mouth is an especially bad case of points.

Wave mouth is when the table surface of the teeth is uneven.

Smooth mouth is when the grinding surface of the teeth is worn smooth in an older horse.

Alveolar Periostitis is infection of the tooth socket. A root canal must be performed.

Dental Formula

I= incisor I1= central incisor I2= middle incisor I3=corner incisor

Pm = premolar M=molar C= canine

Deciduous dental formula

2 ( Di 3/3 Dc 1/1 Dpm 3/3 )= 28

Permanent dental formula 2 ( I 3/3 C 1/1 Pm 3-4/3 M 3/3) =40

Aging the horse by his mouth

Looking to see what the color, shape, and presence of dental markers present.

When looking at the tooth we can only see part of the neck-portion covered by gum.

• Nor can we see the fang or root- which are imbedded into the bone.

• We do see the crown of the tooth, which is composed of (outside to inside) the cement, dentine, central enamel, and infindibulum. Later we will see the pulp cavity.

• We do see the infindibulum as "the cup"

eruption of the temporary teeth,

the replacement of the temporary teeth and the

presence of other markers

Primarily we use the:

shape and disappearance of the cupsthe appearance and position of the dental

starthe shape, position and disappearance of

the enamel ringshape of the table surfaceslength of the crown, angle of the teeth,

Galyvayne's GroovePresence or absence of the 7 and 11

year hook.The determination of age from one to six

years of age are based primarily on the appearance of the incisor teeth. Look at above factors, especially the presence

of the cup. Cup disappears about 3 years after eruption of tooth.

Check for permanent incisors. None? Horse is under 2.5 years old.

Central, middle, and corner incisors break through at 2.5, 3.5, 4.5 years of age. In wear within 6 months.

Central, middle, and corner incisors lose cup at 6,7, and 8 years, respectively. Upper central incisors lose cup at 9,10,11 years.

Central, middle, and corner incisors gain star at 8, 9, and 10 years of age.

Central, middle incisors become round at 9, 10 years of age.

Teeth become triangular at 16, 17 years.