Dental extraction

• Mobile teeth.
• Periodontal disease Periodontal disease.
• Supernumerary teeth: if affecting occlusion or crowding other teeth.
• Persistent deciduous teeth Retained temporary teeth (Persistent primary teeth).
• Advanced caries.
• Fractured teeth Dental fracture: if beyond repair, eg long axis root fractures, root fractures in the middle third, teeth with crown fractures when no endodontic treatment is authorized.
• Teeth on fracture line of fractured mandible or maxilla.
  Skull smaller and more fragile in cat than in dog.

• Endodontic techniques.
• Restorative techniques.

Criteria for choosing test

• Ensure client understands that general anesthesia is necessary.

Minimum equipment

• Scalpel blade No. 11   and handle.
• Molt p9 periosteal elevator .
• Root tip pick.
• Svenska luxators   : 3 mm straight, 3 mm curved.
• Lindo-Levien elevators: LLL, LLM, LLS.
• Needle holder   .
• Fine-toothed dissecting forceps.
• Straight scissors 5 inch   .
  Must be sharp.
• Dental elevator: a selection of sizes to match tooth root size and diameter.
• Cutting burrs     : 701, 702, 330, round 2, 3, 4 and 5
• Bone file  .
• Drapes, clips, swabs.

Minimum consumables

• Suture material: monocryl 1.5 metric rapidly absorbable suture with swaged on cutting needle.

• Opioid .

• Mouth prop.
  Avoid using sprung mouth gags in cats as can cause serious muscle damage.

Step 1 - Single-rooted teeth

• Cut epithelial attachment at bottom of sulcus with No. 11 blade at 25° to long axis of root.
• Select an elevator or luxator with correct blade.
  Select blade with circumference one third the size of a target root.
• Introduce the elevator/luxator in an apical direction between alveolar bone and root surface .
• Rotate luxator blade circumferentially while maintaining apical pressure .
• Stop from time-to-time to allow the hydraulic pressure of hemorrhage from periodontal ligament to assist expulsion of root from alveolus.
• Continue working luxator against all surfaces of root until loose .
• Extract loose root .
• Debride alveolus, removing bone spikes .
• Radiograph to ensure complete removal.
• Suture gingiva.

Step 2 - Multi-rooted teeth

• Create one or more single roots for extraction.
• Break down epithelial attachment (see single-rooted tooth - earlier).
• Lift full-thickness mucous membrane and gingiva from bone using Molt elevator .
• If necessary incise gingiva at caudal and mesial margins diverging away from root axis.
• Remove semi-circle of crestal bone, using 701 cross-cut taper fissure burr, to identify furcation angle.
• Split tooth in two halves cutting from furcation coronally.
• Apply elevator into cut channel and gently rotate to push two roots apart.
• Hold pressure for 10 seconds then turn blade around and repeat procedure.
• Combine with longitudinal elevation of tooth root.
• Keep applying pressure until one or both roots becomes loose.
• Remove loose root.
• Elevate remaining root normally.
• Debride, filing off bone spikes.
• Suture gingiva.
• Radiograph to ensure complete removal.

Step 3 - Upper canine

• Sever epithelial attachment (see single-rooted teeth).
• Locate end of root by digital palpation following lateral canine eminence.
  Locate 2 mm rostral to rostral margin of root to avoid post-extraction suturing over a void.
• Extend incision forward to caudal margin of corner incisor and caudal to mesial root of lower premolar 2.
• Use Molt elevator to lift full thickness mucoperiosteal flap from leading margin at mesial angle of canine backwards to expose lateral canine eminence.
• Use a 701 cross-cut fissure burr or similar high speed, water cooled handpiece.
• Insert a luxator blade into the mesial channel down the long axis direction and rotate in a lateral direction.
• Repeat until periodontal ligament begins to loosen.
• Apply the blade to caudal channel in a similar direction and rotate.
• Repeat from side-to-side until root loosens and can be gently lifted from the socket with forceps.
• Gently irrigate the socket with saline 0.05% chlorhexidine gluconate.
  Blood or fluid from ipsilateral nostril indicates a fistula (see complications).
• Suture flap, using interrupted sutures. Start at leading edge of flap nearest caudal margin of upper incisor.
  ESSENTIAL that sutures are not under tension otherwise dehiscence will occur.

Step 4 - Lower canine

• More difficult than extracting upper canine tooth: long axis of tooth is buccolingual rather than dorsoventral; apex lies at caudal end of mandibular symphysis .
• Sever epithelial attachments as for single-rooted teeth .
• Incise oral mucous membranes on lingual aspect along the long axis of tooth from mesial margin .
• Cut channel round outline of root on lingual aspect to mid root depth or remove lingual bone plate with bone chisel.
• Apply luxator blade to caudal channel along long axis of root - rotate blade while applying pressure apically to rotate root out of alveolus.
• Repeat process in reverse with blade in mesial channel.
• Irrigate and suture (see upper canine extraction).

Step 5 - Deciduous teeth

• Indications: crowding. Most common is lingually displaced mandibular canines with the tips of the lower canines occluding into the hard palate.
• All deciduous teeth are rostral to their permanent counterparts with exception of lower canines which are buccal to permanents.
• Extraction follows same principle as permanent teeth, but deciduous teeth more fragile and prone to fracture.
  Excessive luxation may damage permanent tooth if it is undergoing amelogenesis at this time - important to know location of permanent tooth bud.
• Pre- and post-extraction radiography is very useful.

Analgesia

• Opioid administered pre-operatively or intra-operatively.

Antimicrobial therapy

• Antibiotics: good bone penetration; gram-negative anaerobic spectrum Clindamycin.

Potential complications

Oro-nasal fistula (ONF)

• At any location most commonly upper canines and caudally to them, where bone plates thinnest, ie medial to upper canine and upper premolar 4.

Flap dehiscence

• Requires complex flap surgery. Correct attention at the time of extraction can limit the need for complex flap surgery later. Debride socket gently with 0.05% chlorhexidine gluconate and suture the tissues closed without tension. Treat with suitable antibiotics. Review after 4-6 weeks to identify the need for flap surgery.
• Most commonly caused by tension on sutures or active infection at site.
  Expect 20% contraction of soft tissues during healing.
• Many oro-nasal fistulae stay open due to pressure differential between nasal and oral cavity.
• After 6 weeks, if ONF present, closure is indicated Oronasal fistula repair otherwise chronic rhinitis will occur (although may not be clinically apparent).

Hemorrhage

• Most sockets stop bleeding quickly post-extraction with little need for attention beyond gentle pressure.
• Packing socket with polylactic acid granules (expensive) or bone graft (cheap) may help.
• Hemostatic gauze may help but has to be removed after a short period.
  Beware of clotting factor defects. Pre-test clotting factors to assess suitability for surgery or bleeding time .
• Hospitalize overnight if necessary.

Root fracture

• Common with poor technique. Carnivore teeth taper towards the apex. Over-robust and impatient elevation will fracture the root.
• A fractured fragment containing necrotic pulp or in an infected periodontal pocket will cause bone lysis and must be removed:
  Either Use a root tip pick or fine blade luxator to loosen and remove root tip.
  Or Burr away part of the bone plate to remove the root tip.

Mandibular body fracture

• Beware of extensive bone loss predisposing to fracture.
  Pre-operative radiography may be helpful in assessing risk.
• Support body of mandible with the palm of the hand during tooth elevation.

Mistaken removal of permanent tooth

• Use radiography to differentiate temporary from permanent tooth - temporary teeth may have a less distinct root morphology.
  Do not extract tooth unless sure it is temporary - seek expert advice if necessary.

• See under Aftercare/Complications.

• See earlier.

Refereed papers

• Recent references from PubMed and VetMedResource.
• Wiggs R B, Lobprise H, Mitchell P Q (1998) Oral and periodontal tissue. Maintenance, augmentation, rejuvenation and regeneration. Vet Clin North Am Small Anim Pract 28 (5), 1165-1188 PubMed.
• Smith M M (1996) Lingual approach for surgical extraction of the mandibular canine tooth in dogs and cats. JAAHA 32 (4), 359-364 PubMed.
• DuPont G (1995) Crown amputation with intentional root retention for advanced feline resorptive lesions - a clinical study. J Vet Dent 12 (1), 9-13 PubMed.
• Scheels J L, Howard P E (1993) Principles of dental extraction. Semin Vet Med Surg Small Anim 8 (3), 146-154 PubMed.

Other sources of information

• Wiggs R B, Lobprise H B & Lipincott-Raven (1997) Veterinary Dentistry, Principles and Practice.