Dr. Murat ÇALIŞKAN Exodontics

Exodontics

Dr. Murat ÇALIŞKAN

Small Animal Dentistry A manual of techniques Cedric Tutt

www.vet-dentist.com Blackwell Publishing

The lateral incisor was damaged and the middle incisor is missing in this patient. There was no history of trauma but these injuries must have occurred before the animal was three months of age judging by the enamel defects on the canine.

The mandibular right canine and third premolar are fractured with chronic pulp exposure. Restoration and root canal therapy is

contraindicated in these teeth, where the fractures extend sub- gingivally.

fractured teeth which cannot be restored

• teeth affected by caries (lesions so severe that restoration is not possible)

• persistent deciduous teeth

• supernumerary teeth causing crowding

• maloccluding teeth

• teeth in a jaw fracture line (which are not providing fixation stability)

Indications for tooth extraction

• periodontally compromised teeth

• severe chronic gingivo-stomatitis

• malformed teeth causing gingivitis and periodontal disease

• luxated or subluxated teeth (including intruded teeth) not amenable to treatment

• retained (unerupted) teeth

• teeth affected by odontoclastic resorption

This patient was

kicked in the mouth by a horse and suffered

multiple fractures of its teeth.

The lateral incisor was

damaged and the middle incisor is missing in this patient.

The mandibular right

canine and third premolar are

fractured with chronic pulp exposure.

Restoration and

root canal therapy is

contraindicated in these teeth, where the fractures

extend sub- gingivally^.

Persistent deciduous canine teeth should be extracted before they compromise the permanent dentition as they have in this case.

Supernumerary teeth should be extracted if they cause crowding or compromisation of the adult dentition.

The ‘peg tooth’ in left figure. Note the severely dilacerated root.

A draining sinus on the cheek or face is often an indication of periapical pathology.

Purulent exudate was found at the apex of this canine tooth even though the crown was intact.

Haematogenous infection (anachoresis) of the root and pulp is the most likely cause.

Teeth associated with oral tumours are most

commonly extracted.

A surgical extraction kit should comprise:

periosteal elevator, Adson’s tissue

forceps,

No. 3 scalpel handle, Metzenbaum surgical scissors,

material scissors needle holder.

A

Important

structures to consider when planning

extractions:

A = thin alveolar bone labial to

incisor teeth

B

B = a branch of the majör palatine artery passes through

between the canine and lateral incisor and bleeds profusely when severed (digital

pressure effects haemostasis)

C = the mental neurovascular bundle exits the

mandibular canal at the middle mental foramen^;

c

orbital

neurovascular

structures exit the infraorbital

canal here;

D

E= there is very little alveolar bone distal to the caudal maxillary molar (periodontal

disease can destroy all of this bone);

E

F(inset) = the orbit is

unprotected caudal to the

maxillary second molar;

* = the globe!

Severing the periodontal ligament

mesially using a Luxator®.

Severing the periodontal ligament distally using a Luxator®.

Luxation and elevation instruments must be held using the palm grip.

An elevator correctly held.

The luxation instrument is used to sever the periodontal ligament circumferentially around the tooth.

The Luxator® creates space for the elevator to fit into by

compressing the alveolar bone.

The index finger must be extended along the shaft of the Luxator® to protect tissues should it slip off the bone or tooth

Once the ligament is severed

circumferentially begin luxating lingually /

palatally.

Luxating distally. Luxating mesially. Note the rotational force applied to the Luxator® moving the tooth away from the alveolar wall.

Using a Luxator® to deliver the tooth

Do not use Luxators® and elevators in the manner in which one would use a screwdriver to lever the lid from a paint can!

Canines and maxillary lateral incisors have large, strangely

shaped roots which can complicate the simple extraction

technique and should therefore be extracted surgically.

Following simple extraction the alveolus may be allowed to heal by second intention or an apposing suture may be placed in the gingiva to hold the clot in place, preventing impaction of food and other debris and promoting first intention healing.

Suturing is desirable unless the alveolus is infected.

Stages in raising and

closing a mucoperiosteal flap^{. A:}

A gingival incision is made with releasing incisions mesially and distally.

The releasing incisions are made perpendicular to the gingival incision to preserve blood supply to the gingiva.

B:

A periosteal elevator is used to raise the

mucoperiosteal flap from the alveolar bone.

C:

The flap is raised to expose the juga (bony alveolar

bulge covering the root) of the tooth to be extracted.

D: An alveolotomy is performed removing bone to expose the periodontal ligament.

E: A luxation instrument is used to sever the

periodontal ligament and dislodge the tooth from its alveolus.

F: The flap is sutured back in place using synthetic

monofilament absorbable suture material.

G (from left to right):

Luxation and elevation instruments are used to dislodge the tooth from its alveolus.

The alveolar bone is used as a fulcrum

against which rotational forces are applied.

Alveoloplasty is

performed prior to flap

closure to ensure the flap is not traumatised by

sharp alveolar edges.

Mucoperiosteal flap access for extraction of multi-rooted teeth.

A: The gingiva is incised by placing the scalpel

blade into the gingival sulcus / pocket and

incising down to the alveolar margin.

The releasing incisions are made perpendicular to the gingival margin and at the line angles of the tooth / teeth to be

extracted or the adjacent teeth.

B: A small envelope flap is raised to expose the

furcation of the tooth to be extracted.

C: The crown of the tooth to be extracted is

sectioned from the furcation through the crown and a wedge of crown may be

removed.

D: The mucoperiosteal flap is raised by inserting the

periosteal elevator under the periosteum apical to the mucogingival line

and working it in a coronal direction before

progressing rostrally and caudally.

E: The flap is raised and

reflected to reveal the juga (bony alveolar bulge) over the roots.

F: Alveolotomy is

performed to expose the periodontal ligament for a distance of about three quarters of the length of the roots.

G: Luxation and

elevation of the crown / root segments is

performed

H: The flap is closed without tension, using synthetic monofilament

absorbable suture material.

If there is tension in the

flap, a periosteal releasing incision should be made.

I: (Top to bottom): The tooth is luxated and then elevated using alveolar bone as a leverage

fulcrum. Alveoloplasty is performed prior to flap

closure to prevent damage to the flap from sharp

alveolar edge

Extracting three-rooted teeth

The maxillary carnassial and molar teeth usually have three roots in dogs.

In the cat the maxillary carnassial has three roots and although the maxillary molar may have two or three roots the buccal roots are usually fused

When ‘important’ teeth (canines and carnassials) have been extracted, occlusion of the remaining

teeth must be evaluated to ensure that they do not cause trauma to the opposing tissues.

The mandibular carnassial tooth (molar 1) may bite into the palate after the maxillary

carnassial tooth (premolar 4) and molar 1 have been extracted.

This tooth may require odontoplasty to shorten the crown to prevent palatal trauma.

The palatal cusp of the maxillary left molar 1 is being sectioned.

The palatal cusp of maxillary right carnassial is being sectioned. The bur should be directed at about 45° between the palatal and buccal cusps.

The buccal cusps of the maxillary right molar 1 are being sectioned.

The buccal cusps of the maxillary right carnassial tooth are being sectioned.

The three crown

segments of maxillary right molar 1.

The three crown segments

of maxillary right carnassial tooth.

Possible complications associated with extractions

The mandibular molar 1 and maxillary

carnassial tooth roots can have a developmental groove running from the furcation to the apex of the root. These grooves provide additional anti- rotational support to these teeth and can result in their extraction taking longer than expected.

The carnassial teeth have longitudinal

developmental grooves (distally on the mesial root and mesially

on the distal root) which improve anti- rotational stability.

These can

complicate extraction of these teeth

In geriatric animals the periodontal ligament space is narrower than in young animals and the alveolar bone more dense.

This can complicate extraction as access to the

periodontal ligament space is limited and the alveolar bone is not easily compressed during luxation and

elevation.

Greater patience is also required to prevent iatrogenic root / crown fractures

Iatrogenic oro–nasal communication often occurs when periodontally compromised maxillary teeth are extracted as a result of bone loss affecting the palatal alveolar wall. Sometimes the only separation between the tooth and the nasal passage is inflamed soft tissue which tears loose during extraction. Bleeding is usually noticed from the ipsilateral nostril.

A mucoperiosteal flap

was raised to extract the maxillary left canine and premolars and an oro-

nasal communication resulted at the canine alveolus. The nasal passage was visible through the alveolus.

The acute oro–nasal communication was repaired by tension- free closure of the mucoperiosteal flap and healed

uneventfully.

Entrapment of the upper lip by the left mandibular canine tooth following extraction of the left maxillary canine tooth