SUBDISCIPLINES OF VDOS
Please click on each item below to learn more about the many subdisciplines of veterinary dentistry and oral surgery (VDOS):
"It's much more than just scraping teeth."
Oral Examination and Dental Radiology
Detailed examination of extraoral and intraoral structures and thorough dental, periodontal and oral charting are performed to record abnormalities and allow for appropriate treatment planning. Dental records are legal documents and help determine arrest or progression of previously present pathology. Dental radiography is essential for diagnosis and treatment of dental and periodontal conditions. Full-mouth dental radiographs are usually obtained of all cats and any new patients. Radiographs of the head (skull) are utilized when dental films or digital sensors do not provide enough surface area to visualize all areas of interest.
Maxillofacial Computed Tomography Interpretation
Computed tomography (CT) is a useful tool for the diagnosis of disease and treatment planning for various conditions of the head, including lesions of the nasal cavity and sinuses; disorders of the temporomandibular joint; fractures of the skull, and oral and maxillofacial tumors. It is of great value for exploration of a large volume of soft and hard tissue in a relatively short examination time. This is particularly important when a rapid diagnosis is needed for patients with head trauma or uncertain head pathology and those that are less than optimal anesthesia candidates. CT is very helpful in detecting lesions of hard tissues (such as bone) which is imperative when defining tumor margins and planning radical surgical excision. Cone-beam CT is a variation of diagnostic imaging modality, providing even greater detail for the study of affected hard tissues.
Dental Cleaning and Closed Periodontal Debridement
Professional dental cleaning and closed periodontal debridement refer to removal of plaque and calculus (tartar) and elimination of diseased periodontal tissues. This is accomplished with hand instruments (scalers and curettes) and power instruments (various sonic and ultrasonic scalers). Gingival and subgingival curettage are utilized in conjunction with closed root planing to remove the inflamed and infected soft tissue lining of the periodontal pocket. Once all tooth surfaces are cleaned and gingival tissues have been debrided, the teeth are polished with a fine polishing paste and a rubber cup. Perioceutic treatment involves insertion of low-dose antimicrobial gels into cleaned periodontal pockets after root planing and gingival curettage to enhance healing and connective tissue reattachment.
Local and Regional Anesthesia and Analgesia
Local and regional anesthesia/analgesia is commonly performed in cats and dogs with dental, periodontal, oral and maxillofacial disease. It is an effective measure in reducing the concentration of an inhalant anesthetic needed, thus minimizing complications from hypotension, bradycardia and hypoventilation. Consequently, such patients should recover more quickly and with fewer complications. Local and regional anesthesia also provides analgesia in the postoperative period, thus improving the patient’s comfort and decreasing the need for systemic analgesics.
Periodontal Surgery and Implantology
The goals of periodontal surgery include elimination of plaque-retentive areas, reduction of periodontal inflammation, and regeneration of periodontal tissues. The choice of periodontal surgery depends on the type and severity of periodontal disease. Flaps are reflected to allow for tissue debridement, osseous surgery, and placements of osteopromotive materials and then repositioned at varying locations. Sliding flaps, gingival grafting and guided tissue regeneration are procedures designed for creation of physiologic periodontal morphology. Apical positioning flaps are used for crown-lengthening procedures of teeth fractured close to or below the gum line to allow for placement of prosthodontic crowns in working dogs. Gingivectomy and gingivoplasty are procedures to eliminate pseudopockets in patients with gingival enlargement. Osteointegrated implants can replace lost teeth.
Closed and Open Tooth Extraction
Tooth extraction is a surgical procedure. The most common indications for tooth extraction in dogs are periodontal disease and tooth fracture, and in cats tooth resorption and stomatitis. If the disease process is too advanced for the teeth to be saved, extraction is necessary. Financial and other considerations may lead the client to request extraction. There are two techniques, closed and open extraction. Closed extraction is performed without raising a flap. Open extraction requires creation of a periodontal flap and removal of alveolar bone in order to loosen the tooth from its attachments to the jaws. "Full-mouth" extractions are sometimes performed for treatment of severe oral inflammatory conditions such as stomatitis in cats.
Vital, Standard and Surgical Endodontics
Trauma is usually the cause of fractured canine and carnassial teeth in the dog. Tooth resorption may result in crown fractures in cats, with root fragments remaining in the jaws. Vital pulp therapy is primarily utilized for ‘recent’ tooth fractures or after intentional surgical crown reduction to preserve pulp vitality and increase the strength of the tooth by allowing continued dentin formation. Pulp exposure allows bacteria to enter the tooth, resulting in pulpal inflammation and necrosis, which ultimately leads to periapical disease and abscess formation. Standard root canal therapy is then needed to prevent loss of the tooth. Surgical root canal therapy is occasionally required and involves removal of the tip (apex) of the root. Luxated and avulsed teeth require repositioning, stabilization, and endodontic therapy due to the likely loss of blood supply to the pulp.
Operative Dentistry and Prosthodontics
The goal is to restore the tooth and its function as close as practical to its natural state before the occurrence of disease or trauma. Indications for operative dentistry include fractured teeth, bonding for enamel hypoplasia and other defects, and management of dental caries and tooth resorption. Restorative materials such as composites, glass ionomers and combination products (compomers) have largely replaced amalgam. Extra retention of restorative materials to the tooth can be achieved by the use of pins and posts. The ultimate restorative, however, are prosthodontic crowns which are primarily utilized to restore and protect fractured or weakened teeth of dogs that put their dentition at risk of trauma (e.g., police dogs).
Orthodontics and Genetic Counseling
Orthodontics deals with the diagnosis and treatment of dental and skeletal malocclusion. The goal is to provide the patient with a pain-free and functional bite. Neutering should be done to rule out the possibility of transferring genetic components of malocclusion to offspring. Interceptive orthodontics is defined as extraction of deciduous or permanent teeth that cause malocclusion. Passive orthodontic movement is achieved with a direct inclined plane which is commonly utilized for treatment of lingually displaced lower canine teeth (base-narrow or instanding mandibular canine teeth). Buttons and elastic chains are typically utilized to actively move rostrally displaced upper canine teeth (lance teeth, spear teeth). Rather than performing extraction or orthodontic movement, the crown of a maloccluded tooth that causes trauma to adjacent structures may be reduced in length. This requires sterile instrumentation for the vital pulp therapy after surgical crown reduction.
Oral and Maxillofacial Trauma Management
Jaw fractures and oral and maxillofacial soft tissue injury may be due to automobile trauma, falls, kicks, hits, gunshots, and fights with other animals. Pathologic jaw fracture often occurs secondary to severe periodontal disease. Following stabilization of life-threatening injuries and control of blood loss, soft tissue injuries are cleaned, rinsed and sutured closed. Several techniques are available for successful jaw fracture repair. They include non-invasive and invasive techniques. Non-invasive techniques make use of the teeth as anchor points for stabilization devices and include maxillomandibular fixation, circumferential wiring, interarch wiring and splinting, and interdental wiring and splinting. Invasive techniques are sometimes required and include intraosseus wiring, external skeletal fixation, and bone plating.
Temporomandibular Joint Surgery
Patients with temporomandibular joint (TMJ) problems may have difficulty either to open or to close the mouth. Acute TMJ luxation is treated by manual reduction and tape muzzling to prevent recurrence of luxation. Chronic luxation may require surgical removal of the mandibular condyle. Open-mouth jaw locking can occur when the mouth is opened wide and the coronoid process of the mandible locks ventrolateral to the zygomatic arch. This is commonly confused with TMJ luxation but warrants an entirely different treatment. Acute treatment consists of opening the jaw further to release the coronoid process from the lateral aspect of the zygomatic arch and then closing the mouth. Definitive treatment involves partial resection of interfering bones. The latter surgery is also required in typically young patients with TMJ ankylosis (fusion of the bones that form a joint).
Oral and Maxillofacial Tumor Surgery
The oral cavity is the fourth most common site of malignant neoplasia in dogs and cats (predominately malignant melanoma, squamous cell carcinoma, fibrosarcoma, and osteosarcoma). Obtaining and examining a biopsy specimen allows the clinician to establish a diagnosis, formulate a treatment regimen, and give the owner information regarding prognosis. Describing the clinical extent (staging) of the malignancy is an essential prerequisite of rational treatment and typically involves aspirating enlarged lymph nodes and obtaining thoracic radiographs. The treatment of choice for most oral and maxillofacial tumors (lip, cheek, tongue, tonsil, mandible, maxilla, palate, etc.) is wide surgical excision. Most mandibulectomies, maxillectomies, and other radical surgeries can be performed without significant compromise of quality of life.
Maxillofacial Reconstruction and Oral Rehabilitation
There is a wide variety of reconstructive surgery available, including palate defect surgery (see below), commissuroplasty (a forward advancement of the lip commissure to prevent the tongue from hanging out to the side of the mouth after mandibulectomy procedures), lip and cheek reconstruction (with axial pattern skin flaps that are harvested from the head or neck), and jaw bone defect management (with osteoconductive, osteoinductive or osteogenetic grafts). Principles of microsurgery (vessel anastomosis and nerve repair) are also applied, including free microvascular tissue transfer.
Palate Surgery and Palatal Prosthetics
Congenital defects of the formation of lip and palatal structures may be inherited or result from an insult during fetal development. Palate defects acquired after birth result from severe periodontal disease, trauma, cancer, and surgical and radiation therapy. Cleft lips rarely result in clinical signs beyond mild local rhinitis, and repair may be performed for aesthetic reasons. Cleft hard and soft palate defects are best repaired in animals of three to four months of age. Preoperative management requires nursing care by the owner, which includes tube feeding to avoid aspiration pneumonia. Acquired palate defects are either repaired surgically or—if applicable—by placement of a silicone or acrylic obturator. Brachycephalic patients with respiratory problems may benefit from surgical expansion of nostrils (naroplasty) and shortening/thinning of the soft palate.
Surgery of the Salivary Gland-Duct Complex
Swelling is the most common sign of salivary gland disease and is caused by firm enlargement of the gland itself (inflammation, infection, necrosis, neoplasia) or by soft accumulation of saliva in an abnormal area (salivary mucocele). The swelling may be on the side of the face, below the lower jaw, under the tongue, in the pharynx, or beneath the orbit causing the eye to bulge outwards. Biopsy of the swollen gland will help determine benign or malignant pathology, requiring medical therapy or surgical resection. Injuries to the salivary glands and their ducts may result in formation of a mucocele. Marsupialization is a procedure that creates a large opening into the mucocele through which saliva can drain into the mouth. However, this treatment has a tendency to fail and is therefore less successful than complete resection of the involved salivary gland(s).
Oral Medicine (Inflammatory, Infectious, Neoplastic)
Some autoimmune diseases manifest along the lips or inside the mouth (pemphigus vulgaris, bullous pemphigoid, discoid lupus erythematosus), others affect the masticatory muscles necessary for chewing (masticatory muscle myositis). These and many other conditions of the mouth (e.g., eosinophilic granuloma) can be treated by means of specific medications. However, a soft tissue and bone biopsy is often required for making an accurate diagnosis and for medical or surgical treatment planning. Laser surgery can be performed for ablation of large oral ulcers as can be seen in cats and dogs with focal or generalized stomatitis.
Small Mammal Dentistry and Oral Surgery
This discipline deals with a large variety of special species, including rabbits, guinea pigs, chinchillas, and ferrets. Lagomorphs and rodents kept as pets in captivity are often exposed to diets that are inappropriate for their masticatory apparatus and chewing needs. Tooth elongation and abscess formation with osteomyelitis of the jaws are resulting problems. Early surgical intervention by means of malocclusion correction and diet modification are essential to achieve long-term therapeutic success.
Exotic Animal Dentistry and Oral Surgery
Among oral diagnostic and therapeutic procedures performed on the many large exotic animals, this discipline also deals with smaller species such as birds and reptiles that may have beak, shell, dental, oral and oropharyngeal problems. Examples include dental and oral surgical procedures performed on animals in zoos and other zoo-like collections.
Equine Dentistry and Oral Surgery
Even though modern equine dentistry may have performed over eighty years ago, it has taken a global renaissance of the last three decades to reestablish this discipline as a fundamental area of veterinary science. The level of dentistry and oral surgery provided to horses today has never been so varied. It is important for the welfare of the horse that knowledgeable clinicians perform the equine oral examination, make accurate diagnoses and perform appropriate treatments.