Learning objective. The specifics of Oral and Maxillofacial Surgery which make this subject different from soft tissue or bone surgery at other sites. Instrumentation, materials, suturing, tissue handling, haemostasis and other features of surgery will be discussed. General motto: "The tooth is not bone, the gum is not skin."

Standardisation in medicine is important. The use of standard techniques, instruments and materials recommended for oral and maxillofacial surgery help avoid complications occurring during surgical procedures as a result of medical errors.

Oral and maxillofacial surgery includes numerous procedures with different requirements and levels of difficulty. This specialised branch of surgery includes the following subcategories: tooth extraction, periodontal surgery, palatal surgery, soft tissue surgery, oncologic surgery, fracture repair, temporomandibular joint surgery and surgical endodontics.

Regardless of the surgical subcategory, the standards are similar and must be maintained. The following aspects of these surgical procedures must be considered: pain management, infection control, planning, respect for structures and their anatomy, specific techniques, tactile handling of the tissue and good surgical closure. Of course, these standards relate to any surgical procedure but since the head and particularly the oral cavity has a unique environment, the number of factors influencing the final outcome of an oral or maxillofacial surgical procedure is larger.

The oral and maxillofacial structures must be able to perform regular functions like chewing, swallowing and breathing in the immediate postoperative period. Therefore the shape and tension of wounds must allow normal function.

Pain management. The head is very well innervated and pain sensation is particularly intense here. Postoperative pain affects the patient's recovery and requires serious and efficient management. In dentistry and maxillofacial surgery, pain control must be of the highest standard for all procedures starting in the preoperative period, continuing through the operation and then must be maintained until full recovery of all oral functions. Preoperatively, the use of opioids, sedative drugs (benzodiazepines) and alpha-agonists in premedication as well as NSAIDS for 24 hours prior to surgery prepare the patient and prevent wind-up.

Intra-operatively, the use of local nerve blocks performed correctly and the delicate handling of tissues are two important aspects of the pain management plan.

Postoperative pain management depends on the kind of surgery performed but in most cases is based on the use of opioids at the outset and is continued with NSAIDS provided there are no contraindications for their use.

Infection control. The risk of overuse of antibiotics and the contraindication of the empiric use of antibiotics has to be balanced against the fact that all oral diseases are either initially subject to or complicated by infection. The benefits of antibiotic administration usually come from anaerobe infection control (deep wounds, periodontal abscess, periapical periodontitis or contaminated oral injuries) preventing dissemination and/or the need for treatment of local and regional complications or the management of systemic complications. Some antibiotics (e.g., doxycycline) have additional features, which may be used in immunomodulation of the host response.

Some suture materials are impregnated with triclosan, which additionally controls bacterial activity in the sutured area but studies have shown that they do not increase the safety and efficacy of procedures.

Using antiseptics in the oral cavity is common and very often indicated but an oral rinse with chlorhexidine solution prior to a prophylactic procedure only reduced the risk of bacteraemia in combination with clindamycin.¹ Copious lavage of the oral cavity before and after an oral surgical procedure is routinely performed with 0,12% chlorhexidine solution.

Treatment planning. Many oral surgeries show their best outcome if successful at the first attempt. Because of the numerous structures present in the maxillofacial area, which are vital for functionality and life comfort, a detailed preoperative plan is required including: incision lines, possible access to deeper structures, required flaps, section margins in oncologic surgery and closure of the wound to allow the immediate use of the involved structures. Good preparation for the surgery requires well-documented preoperative diagnostics and consideration of the 3D reconstruction required. Using a tissue marker to draw the incision lines is a valuable procedure.

Structures and anatomy. Good orientation and a thorough knowledge of normal anatomy is a prerequisite for any surgery. In oral and maxillofacial procedures one has to take into account the possible variations in existing structures as well as the abnormalities and pathologies, which change the presence of teeth and other structures. Before the procedure the instrumentation and materials that might be required for the most likely nonfavorable scenarios should be prepared. The innervation and vascularisation must not be compromised by inappropriate dissection.

Techniques: instruments and materials. Although the instrumentation is always organised to meet the personal preferences of the operator, a general requirement is to have clean, autoclaved and sharp instruments and ideally at least one spare kit ready to use. The wide range of breeds, sizes and anatomic features seen in dogs and cats requires different surgical kits for individuals in terms of size, head type and the location of the procedure. Usually, a feline surgery or feline extraction kit is different from one for dogs. Some specific procedures are well described in journals, textbooks and atlases of procedures. It is a good idea to perform less common procedures on a cadaver 1–3 days before the planned surgery and from time to time to do the least common ones just as a refresher.

In general, the best suture material for intraoral use is absorbable monofilament 5/0 or 4/0 material with a taper cut needle. This recommendation is based on studies available in the textbooks.²

Tactile handling. Stay sutures, moistened gauze, saline flushing and all efforts to avoid contamination are important to avoid problems with healing. Force is a last resort and almost never used in dentistry. Instruments with sharp working tips or surfaces help in performing oral surgery in the least traumatic manner.

Wound closure. High standards help to avoid dehiscence and necrosis of wounds in the oral cavity. Tension-free suturing and an appropriate shape and size of flap are of key importance. Flaps planned to cover certain areas have to be larger (approximately 50%) than the size of defect due to postoperative shrinkage.

Generally, absorbable monofilaments are recommended for oral surgery, size 5/0 for cats and small dogs and 4/0 for the dogs. This type of material causes the least irritation and is associated with the least amount of infection. Polyglecaprone 25 is the most popular material but in wounds where slow healing may be anticipated, PDS may be a good option.

Suture needles for oral surgery must be the swaged-on type. Needle curvature is either 3/8 or 1/2 with the latter more indicated in the caudal part of the oral cavity. A reverse cutting needle is the best for suturing gingiva and mucosa but for delicate mucosa, a taper point may be optimal.³

The needle should be inserted into tissues perpendicularly to make the smallest possible entry wound and to avoid tearing of the mucosa.

Double layer suturing in major surgical procedures is better than one layer if possible. A distance of 2–3 mm between the wound edge and the suture entry point and a 2–3 mm distance between interrupted sutures is recommended. In general a single interrupted suture is best and recommended in most oral procedures, although some authors suggest the use of continuous sutures after total extractions in stomatitis patients reduce the time of closure and decrease surgical time. This author prefers the use of simple interrupted hidden sutures in such circumstances. The knot should not be placed directly over the incision. No area of denuded bone should be left uncovered and the suture line should not lie over the defect. However, it is even more important to have tension-free sutures.⁴

References

1.  Bowersock T, Ching Wu, Inskeep G, Chester ST. Prevention of bacteria in dogs undergoing dental scaling by prior administration of oral clindamycin or CHX oral rinse. J Vet Dent. 2000 Mar;17(1):11–16.

2.  Tsugawa AJ, Verstreate FJM. Suture materials and biomaterials. In: Verstreate FJM, Lommer MJ. Oral and Maxillofacial Surgery in Dogs and Cats. Saunders; 2012:69–78.

3.  Dominick ED. Suture material and needle options in oral and periodontal surgery. J Vet Dent. 2014;204–211.

4.  Wiggs B. Oral Surgery in Veterinary Dentistry Principles and Practice. Lippincott-Raven; 1997:232–258.