Oral Examination

Conscious examination is limited to visual inspection and some digital palpation. Examination involves assessing not only the oral cavity proper, but also palpation of the face, temporomandibular joint, salivary glands and lymph nodes. The mouth is first examined by gently holding the jaws closed and retracting the lips to look at the soft tissues and buccal aspects of the teeth. This is the optimal time to evaluate occlusion. A useful checklist for occlusal evaluation is as follows:

 Head symmetry

 Incisor relationship

 Canine occlusion

 Premolar alignment

 Distal premolar/molar occlusion

 Individual teeth positioning

Finally, open the animal's mouth. Most animals allow at least a cursory inspection of the oral cavity once the jaws have been opened. The mucous membranes of the oral cavity should be examined as well as the teeth. Assess the oropharynx if possible.

Definitive oral examination requires general anaesthesia. The oropharynx should be examined prior to endotracheal intubation. Normal anatomical features of the oral cavity need to be identified and inspected. A series of useful checklists are as follows:

Table. Checklists for oral examination.

 Oropharynx:

 Soft palate

 Palatoglossal arch

 Tonsillary crypts

 Tonsils

 Hamular process of the pterygoid

 Fauces

 Lips and cheeks:

 Mucocutaneous junction

 Vestibules

 Philtrum

 Frenula (maxillary and mandibular)

 Salivary papilla (parotid and zygomatic)

 Oral mucous membranes:

 Alveolar mucosa

 Mucogingival line

 Attached gingiva

 Free gingiva

 Hard palate:

 Incisive papilla

 Incisive duct openings

 Palatine raphe and rugae

 Floor of mouth and tongue:

 Sublingual caruncle

 Lingual frenulum

 Lingual salivary gland (cat)

 Tongue papillae (types and distribution)

 Teeth:

 Primary, permanent or mixed dentition

 Missing and/or supernumerary teeth

 Abnormalities in size and/or shape

 Abnormalities in angulation and/or position

 Wear patterns (abrasion, attrition)

 Pathology e.g., caries, enamel hypoplasia, tooth fracture

The periodontium of each tooth needs to be assessed to:

1.  Identify the presence of periodontal disease (gingivitis and periodontitis)

2.  Differentiate between gingivitis (inflammation of the gingiva) and periodontitis (inflammation of the periodontal tissues resulting in loss of attachment and eventually tooth loss)

3.  Identify precise location of disease processes

4.  Assess the extent of tissue destruction where there is periodontitis

The following indices and criteria should be evaluated for each tooth:

1.  Gingivitis and gingival index

2.  Periodontal probing depth

3.  Gingival recession

4.  Furcation involvement

5.  Mobility

6.  Periodontal (clinical) attachment level

In animals with large accumulations of dental deposits (plaque and calculus) on the teeth, it may be necessary to remove these to assess periodontal status accurately

The information resulting from the examination (and any treatment performed) needs to be recorded. A basic dental record consists of written notes and a completed dental chart. Additional diagnostic tests and radiographs are included as indicated. A dental chart is a diagrammatic representation of the dentition, where information (findings and treatment) can be entered in a pictorial and/or notational form. It provides a simple way of recording most of your findings and treatments. However, it is only a chart and needs to be supplemented by clinical notes, radiographs, etc. to make a complete dental record.

Radiography

Radiography is a vital diagnostic tool in veterinary dentistry. Radiographs are required to:

1.  Reach a diagnosis

2.  Plan optimal treatment

3.  Perform certain procedures

4.  Assess outcome of treatment performed

General anaesthesia is required for radiography. Ideally, clinical examination and recording should precede the radiographic evaluation. It is also useful to clean the teeth before any radiographs are taken. Dental calculus, because it is radio-dense, can obscure pathological lesions on a radiograph.

For a dental radiograph to be diagnostic, it should be an accurate representation of the size and shape of the tooth without superimposition of adjacent structures. Intraoral (film placed inside mouth and X-ray beam directed from outside the mouth through tooth and adjacent structures onto the film) radiographic techniques are therefore required. The two basic techniques for intraoral dental radiography are:

1.  Parallel technique for the mandibular premolars and molars

2.  Bisecting angle technique for all other teeth

Extra-oral views are not ideal for dental examination mainly due to superimposition of the contra-lateral side, which obscures the image and causes distortion of the image. However, it may be possible to obtain diagnostic radiographs of the maxillary and mandibular premolars and molars using extra-oral film placement, especially in dogs with wide skulls. Some examiners routinely use extra-oral film placement to radiograph the maxillary premolars and molar in the cat.

Full mouth radiographs describes a series of films where each tooth of the dentition is accurately depicted in at least one view. A full mouth radiographic series provides valuable information, but is not always practically or financially viable. However, it is strongly recommended that all adult cats have full mouth radiographs taken as part of the oral and dental examination. Odontoclastic resorptive lesions are common in cats and clinical examination without radiography will only detect end stage lesions.

In cats, it is necessary to take a minimum of 8 views, but 10 views are recommended, to ensure that all teeth are properly visualised. These are as follows:

Essential:

 Incisor view in the upper jaw (1 film)

 Lateral view for each of the canines of the upper jaw (2 films)

 Left and right maxillary premolar and molar views (2 films)

 Mandibular incisor and canine view (1 film)

 Left and right mandibular premolar and molar views (2 films)

Recommended:

 Lateral view for each of the canines of the mandible (in addition to the 8 essential views)

The choice of film size for each view is subjective. The smallest film that will depict the area of interest should be used to facilitate film positioning. Adult periapical size film can be used for all cat views.

In the case of dogs, full mouth radiographs are encouraged, especially at first examination. If this is not possible then radiographs should be taken where indicated based on the findings during the clinical examination. In the event of full mouth radiographs, the size of film and the number of films used will depend upon the breed of dog and the shape of its face.

Equipment

Equipment and materials for conventional intra-oral radiography include:

1.  X-ray machine ( a dental X-ray machine is preferable to a veterinary X-ray machine)

2.  X-ray film (dental film)

3.  Processing facilities

4.  Mounts or envelopes for film storage

Equipment and materials for digital intra-oral radiography include:

1.  X-ray machine

2.  Digital sensors

3.  Computer and software

Both indirect and direct digital systems are available on the market for intra-oral radiography. The digital sensor replaces conventional film. The advantages of using digital radiography include speed, reduction in exposure requirements and easier storage of patient data.

Interpretation

Radiographic interpretation requires practice. The radiographs of the contra-lateral structures, to those being evaluated, are used for comparative purposes. A good knowledge of the radiographic appearance of normal structures of the upper jaw and mandible is imperative to avoid misdiagnosis.