Equine Dentistry 1 & 2 Flashcards
Anatomy refresher
Describe anatomy of single tooth?
» Cementum
» Enamel
» Dentine
» Secondary dentine at pulp horns
* pulp may lie as little as 2mm below this
» Infundibulae
* Maxillary only
Maxillary cheek teeth?
» 3 roots: 2 buccal, 1 palatial
» 2 infundibulae
» 06 / 07 roots within maxillary bone
» 08/09 roots within Rostral Maxillary Sinus
» 10/11 roots within Caudal Maxillary Sinus
Mandibular cheek teeth?
» 2 Roots: rostral and caudal
» No infundibulae
» Narrower bucco-lingually compared to maxillary teeth
What good Hx questions?
- Has the horse ever seen a dentist?
- If yes when was the last time?
- Did they find any problems / what were their comments?
- What is the horse fed? How often? How much?
- Have you noticed any problems with eating?
- Do you use a bit in the mouth? What type?
- Any other general concerns?
Palpate the head for:
Cheeks
TMJ
Submandibular lymph nodes
Masseter & temporal muscles
Commissure of lips
Lateral excursion to molar contact test
What to look at with incisors?
Malocclusions?
Mucous membrane colour
Diastemata?
Periodontal disease?
Discolouration of teeth?
Ulcers?
Fractures?
Essential dental equipment?
- Gag
- Headlight
- Head stand
- Gloves
- Flush
- Rasps
- Bucket
- Dental charts and pen
- Dental mirror
How to approach dental systematically
- Look at the mouth pre-flushing (any food stassi? hypersal?)
- Examine all arcades in turn
- 3 side -> buccal, lingual/palatal of tooth, surface of tooth)
- Inspect gingiva
- Check the teeth
- Count teeth
Routine dental charting should include:
- findings
- Tx
- Sedation given
- Management adviuce
Re -exam date?
- Most horses 12 months
- If findings ‘severe’ but mostly resolved -9 months
- If findings require more than 1 session to resolve - 3 months
Equine Dental Technicians -> Qualificartions & regulations?
» 2 DEFRA approved organisations regulating EDT’s
» Having a DEFRA recognised qualification allows you to carry out
‘Category 2’ procedures (acts of veterinary surgery)
» Only veterinary surgeons can legally carry out Category 3 procedures
Category 1 procedures?
Procedures that may be carried out by anyone, irrespective of whether they have undertaken any training or have any qualifications
What comes under cat 1 procedures?
- Examination of teeth
- Removal of sharp enamel points using manual (hand) floats only
- Removal of small dental overgrowths (maximum 4mm reductions) using
manual rasps only - Removal of loose deciduous caps
- Rostral profiling of the first cheek teeth (maximum 4mm reductions),
previously termed ‘bit seat shaping’ - Removal of supragingival calculus
Category 2 proceudres must have????
must have passed a DEFRA approved exam to undertake procedures
Category 2 procedures?
- Examination, evaluation and recording of dental abnormalities
- The extraction of teeth or dental fragments with negligible periodontal attachment.
- The removal of erupted, non-displaced wolf teeth in the upper or lower jaw under direct and continuous
veterinary supervision - Palliative rasping of fractured and adjacent teeth
- The use of motorised dental instruments where these are used to reduce dental overgrowths and remove sharp enamel points only
What to be careful with in cat 1 procedures?
- DO NOT OVERRASP!!
- 2ary dentine staining -> dark turn to light brown -> STOP
- If you see any pink/red you have injured the tooth
What cat is wolf teeth removal?
Category 2 -> removal of erupted, non displaced wolf teeth in upper or lower jaw under direct and continuous vet supervision
Describe radiography use
» Essential diagnostic tool for apical infections (tooth root infections) and sinus disease.
» Signs can be subtle.
» CT is much more sensitive!
» Tips:
* Horse must be sedated – no movement blur.
* Take images of both sides for comparison.
* Good image quality requires accurate positioning.
Superimposition?
- Lateral views fo sinuses
- Oblique views for apices ro crowns
Radiograph naming?
- Where coming from
- What angl e
- Where going ot
Describe incisor radiography
» Intra oral:
* Beware of plate damage from chewing!
» Angles will depend on age of horse – bisecting technique.
* Aim perpendicular to a line drawn between occlusal surface and
position of tooth root.
Describe sinus radiograph?
» Lateral view.
» Both sides for comparison.
» Dorsoventral view.
WHAT IS A RELIABLE RADIOGRAPHC FINDING?
- PEriapical Halo
Compare periapical sclerosis & Halo ro normal and to root clubbing
What might you see in an older equine?
» Wide PL.
» Mild halo.
» Mild sclerosis.
» Older equine
List some developmental Incisor Issues
- Malocclusions -> Oberjet or Overbite
- Retained deciduous teeth
- Supernumerary teeth / Hypodontia
Describe overjet?
- Upper incisors rostral to lower incisors.
- Horses cope clinically.
- Cheek teeth – overgrowths on upper 06 and lower 11’s.
Describe Overbite?
- Upper incisors overlie lower incisors.
- More severe CT issues.
- Secondary issues of ulceration.
- Try to correct when young – referral procedure
Describe retained deciduous teeth ?
- Deciduous are usually labial to permanent teeth.
- Displacement of permanent tooth – can resolve with exodontia of deciduous.
- If confusing – radiograph!
- Remove – easy vs. challenging.
describe supernumerary teeth/hypodontia?
- Important to count teeth!
- Often confusing which is normal vs extra – radiograph.
- Leave but monitor – check for wear abnormalities.
List some incisor issues that are ACQUIREd?
- Malocclusions: incisor slant/diagonal
- Incisor wear abnormalities
-Incisor diastema / periodontal dx - Incisor caries
- Incisor fractures
Describe incisor wear abnormalities?
- Primary incisor issue - Missing tooth / fractured tooth.
- Behavioural – crib biting, windsucking (oral stereotypy).
- Age related.
Describe Incisor diastema / periodont dx?
- Often older horses (due to roots tapering).
- Food trapping, rots.
- Management via owners – teeth brushing.
Incisor caries?
- Not common.
- Associated with feed?
- Pain? Carrot test.
- Radiograph, check pulp - may need restoration or exodontia.
Describe incisor fractures?
- Individual tooth fracture.
- Avulsion fracture.
» Repair via removal or endodontics.
What is EOTRH?
Equine Odontoclastic Tooth Resorption & Hypercementosis
Describe EOTRH?
» Resorptive lesions.
» Hypercementosis.
» ?Older horses.
» Carrot test – pain.
» Treatment – extraction ?all ? in stages?
» Client concerns – needs good communication.
* Tongue protrusion
What developmental cheek teeth issues?
- Malocclusions. * Retained deciduous teeth. * Supernumerary Teeth. * Hypodontia (missing teeth). * Dysplastic teeth. * Displacements. * Diastemas.
What Acquired cheek teeth issueS?
- Wear abnormalities. * Caries. * Endodontic dz and apical infection. * Diastema and periodontal dz. * Fractures.
What wear abnormalities do we see in cheek teeth?
- Excessive Transverse ridges (ETRs)
- Sharp Buccal ad Lingual Points (BLPs)
Describe ETRs?
- Transverse ridges are normal – increase surface area.
- Do not remove.
- Beware individual ETR’s – look for a cause (diastema
opposite?). - If abnormal – reduce.
Describe Sharp Buccal and Lingual Points
- Enamel overgrowths.
- Remember anisognathic!
* Mandibular lingual BLPs.
* Maxillary buccal BLPs. - Need reducing to prevent soft tissue trauma.
Describe Rostral or Caudal hooks?
» Count teeth number – may be due to
supernumerary ‘12’ or extracted tooth.
» Beware – exaggerated curve of Spee is NOT
a caudal hook. Check distance from gum
margin compared to other teeth.
How do we reduce rostral or caudal hooks?
Reductions may have to be done in stages:
* Beware iatrogenic pulp exposure.
* May be as little as 2mm beneath surface.
* Water cooling?
Wheek teeth wear abnormalities can either be … or …
- steps -> single overgrown tooth
or - Wave mouth - undulating occlusal curface in ostro-caudal direction
What is Shear mouth?
- > 45°.
- due to minimal side to side mov when chewing
- usually due to pain - check carefully fo an inciting cause
- Reduce over several tx
Calculus on cheek teeth?
» Often found on canines and buccal aspect of upper 06/07/08’s.
» Having removed build up look for a primary cause.
teeth present at birth & first 3 molars?
» Teeth present at birth: 500,600,700,800.
» First 3 molars 06/07/08.
What is shedding time for pre-molar caps?
- 2.5, 3, 4 years
Should you remove pre-molar caps?
» Only remove if loose or causing issues:
* Diastemas.
* Fractures.
* Sharp – mouth ulcers
Eruption cysts are common in ….
3-4yo horses
- Vertical impaciton of teeth
- Predisp to apical infection?
Describe cheek teeth: smooth mouth
» Aged animals, normal physiological process.
» Tooth roots have no enamel.
» Hypercementosis of roots can develop as a
protective mechanism.
» Chewing ability reduced – manage diet.
Describe cheek teeth displacements?
» Can be medial or lateral.
» More common in miniature breeds – overcrowding.
» Varying degrees.
» Care with rasping – beware pulp horns.
» Best treatment may be extraction.
» Often a cause of diastema formation.
What are caries?
» Tooth decay: destruction of calcified dental tissue by bacterial fermentation and acid production
Peripheral caries?
often only cementum secondary to primary diastemata or
periodontal dz.
* Prognosis good – below the gum line healthy cement waits to replace
diseased cement
Infundibular grading of caries?
- 0 none visible.
- 1 Caries of infundibular cementum only.
- 2 Caries of infundibular cement and enamel.
- 3 Caries of infundibular cementum, enamel and dentine.
- 4 Caries of mesial and distal infundibula with coalescence.
- 5 Infundibular associated dental fracture, apical disease or tooth loss.
Tx for Caries?
May be restored according to grade.
* Grade 1-2: monitor, take out of wear.
* Grade 2-4: if > 10mm deep consider restoration.
* Grade 4-5: exodontia.
Describe Diastemas?
» One of the most painful dental disorders.
» Mandibular more common than maxillary.
» Teeth should act as one functional unit.
» Angulation of 06 and 11’s pushes teeth together.
Developmental causes of Diastemata?
» Developmental causes: * Tooth buds too far apart. * Inadequate angulation of 06’s or 11’s. * Overcrowding of teeth / displacements. * Supernumerary teeth. * Dysplastic teeth.
Acquired causes of Diastema?
Secondary displacement.
* Age related.
* Lost / extracted tooth.
CLS of Diastemata?
- None! * Quidding. * Halitosis / Frothy saliva. * Incisor slope / Shear mouth. * Buccal / lingual ulcers. * Food packing. * Nasal discharge (sinusitis). * Jaw swelling.
MOA of Diastemata?
Diastemata tx approach ?
» Treatment often involves management rather than cure.
» Can be expensive as often requires repeated treatments.
» Owners need to be on board – diet changes / mouth
flushing.
» Can get good results but can also be frustrating
How to actually treat diastemata?
- Sedation and pain relief.
- Rasp mouth.
- Pick out and flush.
- Packing with dental putty .
- Extraction of teeth.
- Diastema widening
Fractures can be … or …
Slab fractures or saggital fractures
Cause of fractures?
- Trauma (incisors)
- Idiopathic (cheek teeth)
- Caries
Investigation of fractures?
Endoscope ; radiograph
tx of fractures?
- Removal of segment
- Removal of whole tooth
Route of apical infection in mandibular vs maxillary cheek teeth?
CLS of Apical infection
- Pulp exposure. * Gas bubbles. * Discharging tracts. * Smell. * Fractures. * Caries. * Periodontal disease. * Facial swelling
Imaging of apical infection?
Radiograph & CT
Tx for apical infection
- Endodontic therapy
- Exodontia
What are the different sinuses?
Primary sinusitis can be …
- Acute or chronic
- Idiopathic
- Tx: sinus lavage
2ary Sinusitis?
- Dental dx
- Sinus cyst
CLS of sinusitis ?
- Unilateral nasal discharge… plus…
- Submandibular lymphadenopathy.
- Epiphora.
- Facial swelling.
- Exophthalmos.
- Decreased airflow.
- Neurological signs.
- Pain?
What links between teeth and sinuses?
» Apex of (08),09,10,11’s in close association with the floor of the
maxillary sinuses.
» Examine oral cavity closely
What do we want to determine & do if teeth/sinus issue?
» Radiograph – fluid line? Which tooth is the problem?
» Treat the primary problem via exodontia.
» +/- Trephination to flush sinuses.
Describe sinus cyst / mass?
» Idiopathic, all ages.
» Facial swelling +/- airway obstruction.
» Inhibit sinus drainage causing sinusitis.
» DV or lateral radiograph.
» Needle aspiration diagnostic.
» Good prognosis.
why do we nerve block teeth?
- Analgesic protocols work better if pre-emptive.
- Multi-modal anaesthesia should be routinely employed.
- Allows for decreased sedation.
- Local + sedation eliminates need for general anaesthetic – safer for patient
What are out MAIN nerve blocks & WHAT DO THEY BLOCK?
Infraorbital nerve block - where and what for?
» Rostral end of maxillary nerve – use for removing maxillary
incisors.
» Halfway between naso incisive notch and rostral facial crest.
» Under levator nasolabialis muscle – move dorsally.
How do we DO our infraorbital nerve block
» Need to introduce needle into the foramen as nerve
branches 1cm within the entrance.
» 21g needle.
» 4-8 ml local.
» Exploding nerve block – don’t stand in front of the head!
Where & when do do mental nerve block?
» Blocks rostral aspect of mandible on same side – use
when removing mandibular incisors.
» Foramen is midway between 06 and 03
How to do Mental nerve block?
» 23/25g needle.
» 3-5 ml local.
How do we go about Maxillary nerve block?
» Block at maxillary foramen.
» Sedated patient and STERILE.
» 18 or 19g spinal needle (7-10cm).
Approaches to maxillary nerve blocks?
- Angled.
- Dorsal.
- Perpendicular.
How much fluid in Maxillary nerve block?
10 - 15 ml local - always draw back before injecting
Potential complications for maxillary nerve block?
- Excessive local will cause Horner’s syndrome.
- Haematoma formation post damage to vessels – exophthalmos.
- Keep pressure on eye, if swollen keep moist.
- Symptoms resolve in 48-72 hours.
Where can we find Mandibular (Inferior Alveolar) Nerve Block?
» Also known as inferior alveolar NB.
» Foramen on medial side of mandible
How to find mandibular block site?
» Draw a line from lateral canthus of the eye and dental
crowns. Aim for where these lines bisect.
» Don’t block both sides as equine will traumatise tongue.
Needle, volume & post. op for mandibular NB?
» Use 12.5cm spinal needle.
» 10ml local
» Care post block, wait until worn off before allow eating
or will traumatise tongue
What considerations for doing exodontia?
» Equipment needed = n+1
» Remove the TOOTH, the whole TOOTH and nothing but the TOOTH.
» If you can’t handle the TOOTH – refer!
» Always have a plan B,C,D.
» Oral extraction with sedated patient (CRI vs top ups).
HOW TO Exodontia?
» Sedate – horse.
» Block – tooth.
» Elevate – gingiva.
» Spread – interdental space.
» Stretch – periodontal ligament.
» Extract – tooth.
» Plug – socket
What might be your plans B,C,D (advanced exodontia) ?
- Restoration extraction
- Dental sectioning -> post extraction or pre extraction (crowl removal)
- Fragment extraction
- Minimally invasibe repulsion (MIR)
- Minimally invasive trans-buccal screw extraction (MTE)
