In all endodontic cases, a good intra-oral parallel radiograph of the root and periapical region is mandatory. Radiography is the most reliable of all the diagnostic tests and provides the most valuable information. However, it must be emphasised that a poor quality radiograph not only fails to yield diagnostic information, but also, and more seriously, causes unnecessary radiation of the patient. The use of film holders, recommended by the National Radiographic Guidelines
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and illustrated in Part 4, has two distinct advantages. Firstly a true image of the tooth, its length and anatomical features, is obtained (Fig. 3), and, secondly, subsequent films taken with the same holder can be more accurately compared, particularly at subsequent review when assessing the degree of healing of a periradicular lesion.
A radiograph may be the first indication of the presence of pathology (Fig. 4). A disadvantage of the use of radiography in diagnosis, however, can be that the early stages of pulpitis are not normally evident on the radiograph.
If a sinus is present and patent, a small-sized (about #40) gutta-percha point should be inserted and threaded, by rolling gently between the fingers, as far along the sinus tract as possible. If a radiograph is taken with the gutta-percha point in place, it will lead to an area of bone loss showing the cause of the problem (Fig. 5).
between them. Most pulp testers manufactured today are monopolar (Fig. 6). As well as the concerns expressed earlier about pulp testing, electric pulp testers may give a false-positive reading due to stimulation of nerve fibres in the periodontium. Again, posterior teeth may give misleading readings since a combination of vital and non-vital root canal pulps may be present. The use of gloves in the treatment of all dental patients has produced problems with electric pulp testing. A lip electrode attachment is available which may be used, but a far simpler method is to ask the patient to hold on to the metal handle of the pulp tester. The patient is asked to let go of the handle if they feel a sensation in the tooth being tested. The teeth to be tested are dried and isolated with cotton wool rolls. A conducting medium should be used; the one most readily available is toothpaste. Pulp testers should not be used on patients with pacemakers because of the possibility of electrical interference. Teeth with full crowns present problems with pulp testing. A pulp tester is available with a special point fitting which may be placed between the crown and the gingival margin. There is little to commend the technique of cutting a window in the crown in order to pulp test.