module 11 - Aging by dental exam

enamel spot

appears after the cup has worn down to the bottom

dental star

appears when tooth is worn to pulp space; pulp space filled in with dentin - appears on labial(lip) side of tooth

type of teeth most carnivores have?

brachydont (in humans) -permanent teeth fully erupt before maturity -normally survive for life of animal

how do horses grind down their teeth?

by grinding forage

the second section of teeth are called

canine teeth are in the bridal path -seen in male horses, pops 4 to 5 years of age -about 20-30% of females have them and they're smaller

the back teeth are known as

cheek teeth move causally from the canines

horses teeth have a long ____ which is actually within the gum

crown

details of aging horses - divide horses teeth into two types

deciduous (means transience) teeth (incisors) - baby teeth (I3'S) appearance: rounded or triangular in shape, smooth, no ridges

pulp cavity fills in with

dentin

occlusal surface of tooth

grinding/chewing surface -horses teeth are touching a grinding surface -all teeth have grinding surface

Galvayne's groove

groove on the lateral (Labial) surface of upper i3's 10 years = appears 15 years = 1/2 way down 20 years = all the way down (reaches occlusal surface 25 years = absent from upper 1/2 30 years = disappears

Eruption Times of (adult) Permanent Teeth

i1 = 2 1/2 years i2 = 3 1/2 years i3 = 4 1/2 canines = 4-5 years PM1 = 6 months (wolf tooth) PM2 = 2 years PM3 = 3 years PM4 = 4years M1 = 1 year M2 = 2 years M3 = 3 years

primarily can determine age by the _____ teeth

incisor - appear longer and taller as the teeth get older

The front teeth are called

incisors

vistidual means

left over in evolution

floating teeth means to

level

parts of the horse tooth

long part = crown/ called the body the part that splits = root

incisor teeth

look longer and taller as they age 12 teeth total (6 top, 6 bottom) things to notice -more rectangular, they're permanent -angulation of the INCISOR PROFILE -upper corner incisor, get groves that have staining

layed out into 4 section

looking from the front 1 = upper right 2 = upper left 3 = lower left 4 = lower right

the lower jaw is called the

mandible

The upper jaw is called the

maxilla

surface of the tooth is called the

occlusal surface

enamel spot

occur caudal to the dental star -after the "cup" is finally missing

Stages of incisor wear and ages

oval (transversely, birds eye view) - young round - ~9-10 years triangular - ~16-17 years oval (rostrocaudally) - ~20 years

what are we going to be looking for in a live horse?

physical depressions in the tooth - remember the infundibulum/the cup -we will see the dental star

cheek teeth consist of

pre-molars - have 1-4 small, 3 large ones vistidual tooth/small one = wolf teeth (can have up to 4) -very long -continually erupt until they're old and run out molars - in the back, roughly three -very long -continually erupt until they're old and run out of reserve crown

clinical crown and reserved crown

reserved =. part underneath the gum clinical = part we can see

labial surface of tooth

surface of the tooth facing the lips -upper and lower incisor teeth

lingual surface of tooth

surface of the tooth facing the tongue - all teeth have lingual surface

buccal surface of tooth

surface of tooth against the cheek - pre molars and morals

examine for aging steps

1.) LOOK AT INCISOR PROFILE 2.) determine the # of deciduous and/or permanent incisors 3.) shape of upper 13's (look for galvaynes groove) 4.) examine occlusal surface of lower incisors (CUPS)

Hypsodont teeth

1.) continually grown/erupt 2.) slowly erupt over most of life 3.) long crown (body) 4.) little root

Structures of an individual tooth (3)

1.) pulp -blood and nerve supply of the tooth -incisors/canines single pulp cavity - cheek teeth are complex = 5 compartments 2.)cementum -not very hard -gritty substance that comes off after floating teeth 3.) enamel

permanent dental formula

2 [I3/3, C 0-1/0-1, P3-4/3-4, M3/3]= 36-44 total -variation in number of adult teeth due to the -variability of the presence of 1st premolars (wolf teeth) in males and females -variability of canines in females

deciduous dental formula

2 [dI3/3, dC0/0, dP3/3, dM 0/0 ] = 24 numerator = top teeth (maxilla) denominator = bottom teeth (mandible)

deciduous rule of 8's

1-8 days = i1 erupts 4-8 weeks = i2 erupts 6-8 months = i3 erupts NO CANINES, WOLF TEETH, or MOLARS

terminology 'in wear' = "cup gone" =

"in wear" = when 2 erupted teeth grow enough to meet -erupt --- 6 months ---> in wear "Cup gone" = when tooth reaches bottom of cup

aging generalities

-eruption times of incisors (up to 5 years) -look at upper 1 3's (UCI) shape -height of upper central incisors (I1's) - older = angulated - younger = vertical - wear of upper and lower incisors (FOR LOSS OF CUPS ONLY) - galvaynes groover, incisor profile, and shape of occlusal surface

Horse Skull/teeth

1

official guide for determining the age of the horse ______ guide from 19__

AAEP guide 1966 but we normally use more practice info from a live horse

permanent incisors

Grooved, less white, not a distinct neck, more square/rectanglular in shape

di = dp =

ON EACH SIDE deciduous incisor (1-3) deciduous premolar (1-3) 12 ON TOP 12 on BOTTOM k-9, wolf teeth and molars, DON'T HAVE BABY TEETH

what are the dots in the older horses?

these are the pulp cavity also known as the dental star, they will never disappear