Dental problems that get complicated?

The steady output of publications on the subject of equine dentistry on the literature has fueled improving understanding of the aetiology and risk factors associated with equine dental disease. Technological advances coupled with this have resulted in increased ambition from veterinary dental professionals, technicians and a temptation to attempt any procedure in a field situation. While the efficacy of many treatments remains unvalidated, the complications associated with some of these techniques have been documented. Opportunities for dental training are widespread now but only a minority attend a rigorous assessed post-graduate training programme, as is common in other specialities. It is therefore important for the veterinary dentist, particularly when working alone in a peripatetic setting, to be aware of the possible complications of any procedure, be cognisant of the limitations of their equipment and expertise and to guard against their medical judgement being swayed by excessive ambition, commercial interest or owner pressure.

Most dental procedures are carried out in conscious sedated horses. The planning of any procedure should be preceded by a thorough examination including diagnostic imaging where needed and appropriate, detailed planning and informed consent of the procedure that may be staged on a different occasion. The planning should include: consideration of location and facilities; technical assistance; instrumentation and contingency plans for anticipated complications. Intrinsic to this is the safety of the veterinarian, assistants, owners and the horse itself as a result of a dangerous response of the animal to the stimulation, and the risk of iatrogenic damage if procedures are undertaken in compromised circumstances.

The majority of horses respond favourably to sedative analgesic protocols combined with regional analgesia. These enable quite intrusive surgical and dental procedures to be carried out safely. However with some intolerant patients the risks associated with these outweigh the perceived risks of doing the procedure with the horse anaesthetised and this should be remembered as an option ¹ .

The trend for motorised mechanical devices to perform odontoplasty has improved the efficiency and precision of this when done safely and precisely. Nevertheless in poorly restrained animals such instruments are capable of afflicting iatrogenic dental pulp exposure unwittingly if used improperly.

Odontoplasty for the treatment of periodontal disease removes interproximal dentine that can lie just a few mm superficial to mesial and distal pulp horns. Good restraint and precise treatment guided by oroscopic observation minimise the risk of this. The veterinarian should know and be equipped to performed first aid measures on any iatrogenically exposed dental pulp ² .

Dental extraction per os if performed competently has a low incidence of complications (9%) ³ and is the most effective technique for equine dental extraction. However not all teeth can be extracted thus. Pathologically diseased, fractured or impacted teeth require some form of surgical extraction. All of the more invasive technique require specialised instrumentation, additional training and considerable experience to undertake without high complication rates ^{4, 5}. Newer minimally invasive techniques have superceded traditional repulsion which is largely obsolete due to the unacceptable rate of complications. Such techniques require greater precision, more technical assistance and very careful case selection to enable consistent results ^6,7.

Removal of teeth with fractured crowns, particularly maxillary teeth associated with the paranasal sinuses, caudal mandibular molars and impacted teeth can be particularly challenging. A large array of different equipment is needed to enable all technical possibilities ^8,9. The benefit of CT images that inform treatment selection and possibilities is unquestioned but this three-dimensional imaging modality of only widely available in selected geographical areas such as the United States and Europe. Treatment failure can manifest as failure of exodontia, persistent sinusitis, sequestrum formation, fistula formation and iatrogenic supporting bone fracture ^{10, 11, 12}. When considering a potentially complex treatment the veterinary dentist must consider the resources available to them, the resources of the owner, the availability locally of specialist knowledge and equipment and the contingency for complications to avoid iatrogenic damage, and predict and avoid any of these complications .