Treatment of deep leg vein thrombosis
There is little need to modify anticoagulant therapy for most routine dental treatment. For patients taking warfarin, who are having procedures likely to cause significant bleeding, the physician managing the anticoagulation therapy should be consulted. The treatment may need to be changed depending on the procedure.
Surgery should preferably be undertaken in the morning to permit a reasonable period of immediate postoperative observation.

The medical history taken by dentists should always include an inquiry about any anticoagulant therapy. Patients with a history of thromboses, or with a prosthetic heart valve, are likely to be taking an anticoagulant.

Care should be taken with any injection into a patient on anticoagulant therapy. A new needle for each injection appears to minimise trauma. Injury of a vessel may cause a haematoma. A haematoma associated with a mandibular or maxillary block has the potential for serious complications.

Patients who are taking warfarin may experience interactions with drugs used or prescribed by dentists including aspirin, non-steroidal anti-inflammatory drugs, sulfonamides, metronidazole and erythromycin.

Hepatitis B: issues in laboratory diagnosis and vaccination
Blood-borne viral infections are of concern to dentists and their clinical auxiliaries, assistants and patients. The employment of standard precautions to prevent transmission of blood-borne viruses has provided effective protection. Immunisation of dental clinicians, including their clinical assistants and dental auxiliaries, for hepatitis B has been recommended for many years. It is usually provided during dental training before the teaching of clinical procedures commences. Pre-immunisation testing to assess whether immunisation is in fact needed should take place. This issue has caused considerable concern when dental students or dental professionals are found to have chronic hepatitis B virus (HBV) infection. There are major implications for continuing clinical practice. If clinical practice is not possible for dental students, they are usually unable to complete the dental curriculum.

Of special interest is the serology of chronic HBV infection. Until recently, the absence of HBe antigen was considered to be an indication that a carrier was no longer infectious. Recently, exceptions to this have been established.

If the HBe antigen is found, it is regarded as an indicator of chronic infection; HBe positive dentists are infectious and should stop doing dental procedures.

Acting on advice from infectious disease specialists who are familiar with clinical dentistry, dentists who are chronic hepatitis B carriers, but do not have HBe, may practise a limited range of dental procedures. These exclude exposure prone procedures.

With advances in our understanding of the disease and its serology, it may be possible in the future to review the stringent prohibitions on dental practice which have to be observed by chronic carriers of hepatitis B who are HBe antigen positive.