Large Animal Surgery II: Dentistry

What to check on exam

Range of motion -lateral excursion -equal on both sides — should be able to go 1-1.5 tooth in both directions Full moth speculum essential!! Visual exam -light source Dental mirrors Palapation -full mouth speculum Gloves

What is the most important piece of equipment to enable a thorough oral examination in a horse?

A full mouth speculum

Periodontitis cause and clinical signs

Cause: (common in older animals) -decomposition of packed feed -main cause of apical abscessation Clinical signs: -Gingivitis (not as obvious) -periodontal pockets -mouth pain -dysmastication -tooth loss

Diagnosis of apical abscess

Clincal exam Oral exam radiography — essential Oral/sinus endoscopy Diseased usually advanced at time of diagnosis

Apical abscess treatment

Conservative -long term antibiotics — 2-3 weeks, penicillin -sinus lavage — trephination —> usually unsuccessful Endodontic -apicoectomy -endontic treatment -filling of pulp cavity Extraction (oral or surgical) -fracture + apical infection -extensive root infection -advanced dental disease

Horse dental formula

Deciduous: 330/330 = 12 Permanent: 3(1)3(4)3/3(1)33 = 18-21 ()= may or may not have canine or wolf tooth Diphydont

What makes up the tooth

Dentin: dental cavity, dental pulp (nerves, blood vessels) Enamel -hardest substance, formed ridges and is the grinding surface -creases Cementum -outer surface

What type of teeth do horses have?

Diphydont Heterodont Hypsodont (long crown that grows out over time) Diastema -interdental space between incisors and cheek teeth (term is used for pathological lesions) Curve of Spee: curve up, caudal teeth hard to access Prognathia: overbite — when head goes down to graze the lower jaw fall forward in correct position

When to Examination based on age (5year, 6-15, >15)

Up to 5 years old -every 6 months —> ensure caps are shedding —> cheek teeth in balanced wear —> correct abnormalities early on 6-15 -yearly checks (bridal sits right where the teeth are) -More frequent if abnormalities present >15 years -start losing teeth: frequently dentistry to reduce overgrowth -early correction of steps and waves -periodontal disease

Galvayne's groove

Upper corner incisor -first appears at 10 -reaches half-way down by 15 -completely down by 20 -halfway gone by 25 -completely gone by 30

Hook/notch

Upper corner incisor age 6, disappears by age 8 -reappears at age 14, disappears 1 year later

Ageing by teeth shape and cups

Usually with incisors Shape of the corner incisors -wider than tall <10 -square 10-15 -taller than wide >15 Side of the middle incisors -I1 taller and wider than I2 <10 -I1 = I2 10-15 -I1 narrower and shorter than I2 >15 Cups in lower incisors -I1 gone at 7 -I2 gone at 8 I3 gone at 9

Wolf teeth and indications for removal

Vestigial premolar (PM1) -no purpose -NOT automatically a problem Indications for removal -usually notice at beginning of training -head tossing -unwilling to accept bit on one side -'blind' wolf teeth —> haven't broken through the gums (where the bit fits —> Problem)

Wolf teeth complications

-Broken root — needs to be removed -alveolar fracture — removal of fragments, risk of tooth root disease in adjacent teeth -palatine artery laceration — pack mouth and tape shut -Maxillary fracture

Cheek teeth diastema treatment

-Change diet — remove long fiber foods -remove overgrowths -remove impacted feed — transient improvement, continue eating widening of diastema — best long term results!!

Cheek teeth diastema(ta)

-Most painful EQUINE dental disease -difficult to diagnose -usually, caudal lower cheek teeth affected -a small diastema can be more problematic than a large diastema (large food will fall out) -food trapped between cheek teeth while eventually get packed into periodontal spaces —> periodontitis

Supernumerary incisors

-develop in addition to the 6 normal permanent adult incisors -have long (up to 7cm) reserve crowns -lie close to reserve crowns and roots of normal permanent incisor -usually cause little problem -often best NOT to remove

Complications of apical abscess

-incomplete root removal (most common) -bone sequestrum formation -chronic alveoli this and sinusitis — oro-sinus (oroantral) fistula -removal of wrong tooth -fractured alveolus -damage adjacent tooth -mandibular fracture -fractured hard palate — palatine artery laceration -damage to buccal (facial) nerve or salivary duct (buccotomy only)

Oral extraction of apical abscess

-loose tooth -difficult in younger horses and caudal teeth — long roots, curve of spee -standing and sedation -instruments — dental pick, molar spreaders, molar extractors, fulcrum, molar cutters Least complications!

Eruption bumps

-normal in 3-4 year old horses -issues and vascular changes during root formation and eruption of permanent cheek teeth -non-painful bumps on the ventral mandible (will go away when full grown at 5 years of age) -NO treatment necessary -if hot or painful —> IMPACTION (retained cap) — will need treatment (cap removal)

Apical abscess aftercare

-packing of alveolus — oro-sinus fistula last 3.5 cheek teeth -antibiotic cover -sinus lavage — if involved -regular dental reduction of opposing tooth (biannual) — adjacent teeth will migrate into space in young horses

Retained caps

-premolars — PM 3and4, no deciduous molars so cant have retained — seen 3.5-5 years old -[incisors] occasionally -sharper, inflamed gingiva, ulcerations Signs: -mouthy -quidding -problems with bridling Remove with cap extractor

Wolf teeth procedure

-sedation and local anesthesia —> veterinary procedure!! -loosen with periosteal elevator -rotate extractor to cut maxilla -"scoop" out tooth

Clinical signs of apical abscess

-swelling/draining tract on mandible -maxillary sinusitis — nasal discharge, only if last 3.5 cheek teeth involved -halitosis -bitting issues -quidding -hypersalivation -weight loss -colic -head tilt

Retained deciduous incisors

-usually lie in front of permanent tooth — cause displacement of permeant tooth -if loose remove with forceps (tiny roots) -if firmly attached, remove with dental elevators and local anesthetic of the mental/maxillary nerve (infraorbital foramen or mandibular foramen)

Brachy and prognathia

Abnormal relationship of length of maxilla to mandible -maxilla > mandible -"parrot mouth" -more common in horses Mandible > maxilla -"sow mouth" Can affect just incisors or whole dental arcade —> overgrowth of incisors —> hooks/ramps on 1st and last cheek teeth exacerbated

T/F Wolf teeth are likely to cause bitting issues and should ALWAYS be removed

False

T/F young horses only need to start regular dentist visits once they are being backed (ridden)

False —> want much more frequently, every 6 months easier to correct

Surgical extraction of apical abscess

GA -internasal intubation -steinman pin -buccotomy — mandibular tooth, cut through the cheek (lots of things that can be affected) Standing -maxillary or mandibular nerve block —> repulsion -sinusotomy -trephination

Etiology of apical abscess

Gingivitis and periodontal disease (most common) -> ascending infection -> apical infection and alveolar osteitis Hematogenous (younger) -extensive blood supply to erupting teeth -median age 5-7years Tooth fracture Maldentation 109/209 most common (M1)

Brachy and prognathia treatment

Increase frequency dentristy -includes cutting incisors Braces -wire from PM2 to incisors — need to take off the right time -ethical considerations — HEREDITARY!!, castrated and spayed while doing

What is the most common cause of a step mouth in horses?

Loss of a cheek tooth Unopposed growth of a cheek tooth

Jaw of the horse

Maxilla wider than the mandible Figure of 8 chewing motion —> angulation of teeth 45º normal

Possible signs of tooth issues

Nothing a lot of the time, will eat no matter water -quidding: eating hay, form balled up bits they spit out -packing food into cheeks — typical odor -poorly digested food in feces -bitting or head carriage problems -weight loss — only in extreme cases -unilateral nasal discharge (only on last upper molars, in maxially sinus)

Which method of tooth extraction has the LESAT complications

Oral extraction

What is the main cause of tooth root infection in horses?

Periodontitis

Normal findings

Sharp points -lower lingual -upper buccal Hooks and ramps -predominantly rostral maxillary caudal mandibular due to mild maxillary prognathia when fed in an upright position -feed horse on the ground

What are the parts of a routine dental?

Smooth over points -upper buccal -lower lingual -don't do anything on occlusal surface unless necessary, grinding surface need them! Reduce hooks and ramps (horses that feed with the head up) -rostral maxillary -caudal mandibular —> when horse does put head back and the jaw will not fall forward if you don't fix

Periodontitis treatment and prognosis

treatment: -occlusal equilibration — opposite arcade -removal or packed feed -antiseptic mouth wash — chlorahex -debridement of necrotic tissue -take affected tooth out of occlusion if loose -tooth extraction Prognosis: -excellent with appropriate treatment