Regional Veterinary Surgery

EXODONTIA / DENTAL EXTRACTION

Indications

• The indications for tooth extraction are,
  • Retained deciduous teeth
  • Infected teeth
  • Traumatised teeth
  • Mal occluded and supernumerary teeth
• Normally the eruption of permanent tooth causes the shedding of the temporary one, whose roots are small and rudimentary.
• The cause for failure of shedding of temporary teeth is considered to be due to the failure of the periodontal membrane to detach from the tooth and alveolus.
• Canine distemper may facilitate retention of temporary teeth.
• Retention of the cheek tooth is very rare as the growing permanent tooth virtually push the temporary tooth out. But the permanent incisors and canines being not directly beneath the deciduous teeth, if they are not shed in time, there will be extra number of such teeth.
• In the case of puppies, if the temporary incisors or canines are not shed even by 6-7 months of age, they should be extracted.
• Infection of a dental root with damage to the periodontal membrane is the most common indication for extraction.
• The infection may be either primary bacterial invasion or a sequel to gingivitis.
• In brachycephalic breeds and in certain individuals, short jaws lead to crowding of the teeth and malocclusion. In such cases, it is advisable to extract those maloccluding teeth.

Technique

• The instruments required for dental extraction are root elevators, canine extractors, molar extractors. Small sized hack saw blades, bone chisels, rongeur forceps and periosteal elevators.
• In small animals, general anaesthesia is required to get effective control of the patient. Regardless of type of tooth, the principle of tooth extraction is to displace the root from the socket using a root elevator.
• The first step is to loosen the gums by inserting the elevator completely around the neck between the tooth and gum. The elevator is then inserted around the root, separating it from the remaining attachments

• Loosening the root in the alveolus can be hastened by using the dental extractor to twist the tool gently back and forth. Once the tooth is loosened, the back of the extractor can be used as a fulcrum against the remaining teeth to withdraw the loosened one.
• The upper molar and 4^th premolar teeth present special problems because they have 3 roots. The single posterior root should be separated from the anterior pair before extraction. After loosening the gum from the neck, the tooth is split with a tooth splitter or a small hack saw blade. Once split, the roots can be extracted separately as described earlier.
• The upper carnassial tooth may some times pose difficulty while extraction. In such cases the alveolar resection method is adopted. In this case, the gum over the affected tooth is incised vertically between the anterior and posterior roots. The gum is reflected from the tooth and then the lateral aspect of the alveolus is removed with a mallet and chisel. The root elevator is driven between the roots and by it’s up and down movement, roots are loosened.
• Loosened molars are removed using molar extractors. The cut edges of the gum may be apposed with interrupted absorbable sutures. In the case of canine teeth, their long root and firm attachment present difficulty while extraction. In cases of failure of conventional methods of tooth extraction, the alveolus may be opened using a bone chisel from the neck to the apex of the root, after retracting the gum. The lateral wall of the alveolus is removed and the root is loosened and the tooth is removed. The gingival incision is sutured with interrupted sutures.

Post operative care

• Control of haemorrhage is most important. This is done by packing the alveolus with cotton or absorbable gelatin foam.
• The alveolus should be checked for bone spicules or rough edges and in case of their presence, they should be removed with a burr or a rongeur forceps. Most alveoli fill with granulation tissue and ossify. But if the cavity is very large or when many teeth are removed, the alveoli should be packed with dental wax. This will seal the cavity and as the granulation tissue fill the cavity, this plug will be pushed out.

Post operative complication

• Osteomyelitis, endocarditis and suppurative arthritis are the common sequelae to oral surgery. Hence these can be prevented by providing sufficient antibiotic cover, which should be started a day or two ahead of surgery.