33 Complicated crown fracture with periapical disease
An extremely aggressive dog that only tolerates its owners! The dog needed to be muzzled at all times when in public. The first signs of aggression were noted when the dog was 16 weeks old. The aggression had become progressively worse with increasing age. The owner noticed a change in eating behaviour over the last few months. First, the dog went off its food for a few days and then started to wolf it down without chewing. They then noticed a swelling on the ventral mandible approximately a month prior to seeing us. They consulted their own veterinarian, who referred them to us for examination and treatment of the dog. The referring veterinarian had not been able to perform any examination at all.
ORAL EXAMINATION – CONSCIOUS
Conscious examination of this extremely aggressive dog was not possible.
ORAL EXAMINATION – UNDER GENERAL ANAESTHETIC
A thorough oral and dental examination, including investigating periodontal parameters, was performed. All findings were noted on the dental record sheet.
In summary, examination under general anaesthesia identified the following:
All four canines were mature teeth with closed apices. Periapical destruction and external root resorption were evident with all four canine teeth. The periapical lesions were more extensive in the lower jaw (Fig. 33.1), and had resulted in thinning and expansion of the ventral cortical bone.
ORAL PROBLEM LIST
Complicated crown fracture (CCF) resulting in pulpal inflammation and periapical disease affecting all four canines.
The crown fracture has exposed the pulp, resulting in pulpal inflammation. The teeth are mature, i.e. the apices are closed, so the injury must have occurred when the dog was more than 1 year old. The inflammatory response has spread to involve the periapical region, resulting in destruction of the periapical bone. This is evident as an apical rarefaction on a radiograph. The bone defect is filled with soft tissue, which may be granulation tissue (periapical granuloma), cyst (periapical or radicular cyst) or abscess (periapical abscess). Definitive differentiation between these three possibilities requires histopathology of the tissue. The periapical cyst usually occurs as a sequel to the periapical granuloma. It is a true cyst since the lesion consists of a pathological, often fluid-filled, cavity that is lined by epithelium. Periapical cysts enlarge due to the osmotic gradient set up between the lumen of the cyst and tissue fluids in the surrounding connective tissue. These lesions can become very large at the expense of the adjacent bone tissue, which is resorbed (due to pressure from the cyst). Periapical lesions may be entirely asymptomatic or excruciatingly painful. The periapical granuloma and periapical cyst rarely cause severe discomfort, but they may undergo exacerbation and develop into a periodontal abscess, which usually is an extremely painful condition.
Periapical disease as a consequence of pulpal inflammation is treated by removing the inflamed pulp. This can be achieved in one of two ways, either endodontic therapy (the pulp is removed, the debrided root canal is filled and the access cavities restored, and the tooth is maintained) or extraction of the affected tooth (the whole tooth is removed). The presence of periapical disease is not a contraindication for endodontic treatment. Once the inflamed pulp has been removed, the periapical bone will regenerate and the defect will heal.