It is the dentists’ task to advise their patients what type of mouthguard grants the best possible protection. It is generally accepted that off-the-counter mouthguards are not sufficiently protective. These mouthguards are usually ill- fitting and not worn in the mouth but in the sporting shorts’ pocket instead. A customfabricated mouthguard is proven to offer maximal protection. A mouthguard has to offer adequate protection with high comfort. A composite laminate construction and space between the inner surface of the mouthguard and the labial surface of the upper front teeth are essential for adequate protection. Transitional dentition and/or orthodontic appliances are no limitation to fabricate a custom-formed mouthguard.

The high quality and rigid regulation of dental care in the Netherlands can form a barrier to the implementation of new or expensive techniques. Thus, laser techniques in dental care are quickly dismissed on the basis that they are an (excessively) expensive means of achieving a dental goal which can already be achieved with existing means. The laser, however, brings with it additional possibilities for treatment. Laser fluoresence makes additional caries and periodontal diagnostics possible. Lasers can contribute to the effective flushing of root-canals. Safe cleaning of deep periodontal pockets is also possible with laser technology. Surgery of soft tissue too can be carried out more simply and safely with lasers than with a knife, with the added advantage of less discomfort for the patient. The successful application of laser techniques depends on the use of the correct laser (with an appropriate wave-length and pulse system) for the intended purpose. It is almost impossible for a dentist who is uninformed about lasers to acquire an appropriate instrument in a responsible manner. It is certainly useful to follow a course on lasers before any purchase is made.

The lack of scientific basis for the treatment of mutilated dentition and the lack of a correlation between the loss of molar teeth and oral function were the reasons for carrying out a doctoral research project into mutilated dentitions. According to the thesis, loss of teeth was increased with age and loss of teeth followed a similar pattern in all socio-economic classes. No correlation was found between the number of teeth lost and oral function. Only a weak correlation could be demonstrated between the number of occluding pairs of maxillary and mandibular teeth and subjective chewing ability. Subsequent clinical trials and questionnaire studies revealed that, basically, hardly any convincing reason is available for prosthetic replacement of posterior teeth, providing the presence of 3 occluding pairs of maxillary and mandibular teeth. On the strength of scientific evidence available, one may assume that a sound dentition containing at least 20 teeth, maxillary and mandibular frontal teeth and premolars, is satisfactory functionally and aesthetically. For these cases, any reason for prosthetic replacement is absent.

The randomised experiment in a single patient, the N-of-1 trial, is the best study design for demonstrating causality, for example between agent and effect. Despite this, this type of study is only encountered sporadically in medical journals. One reason for this is that even this type of design cannot definitively demonstrate causality, because different points in time are compared with one another. Moreover, the design is rather inefficient, since the results correspond with those from observation without randomisation, placebo control or blinding. Even so, the N-of-1 trial is the ultimate form of verification in, for example, the individualisation of treatment. For this reason, this form of study might be used more often.

To determine whether there was a connection between the complaint of restless legs and the ingestion of artificial sweeteners in a patient with these symptoms after drinking certain ‘light’ beverages, a randomised, double-blind, placebo-controlled N-of-1 trial with a crossover design was used. During a period of 48 days, the patient took 4 capsules per day containing either 150 mg of cyclamate, 22.5 mg of saccharine, both sweeteners, or placebo on two successive days.Between each of these 2-day periods there was a 2-day rest period during which no capsules were taken. The hospital pharmacist had prepared the capsules and determined the sequence of the 2-day periods on a random basis. The patient did not know which capsules he was taking. Every day on arising, starting 3 weeks before the trial period, the patient noted the intensity and duration of the symptoms in the late evening and previous night. For this notation he used an 11-point scale, from 0 (= no restless legs) to 10 (= almost total inability to sleep because of restless legs). A score of 1-3 corresponded to mild symptoms that had no effect on the patient’s sleep; at a score of 4-6 his sleep was disturbed and at a score of 7-10 the patient hardly slept at all. The patient had symptoms more often while using saccharine or the combination of saccharine and cyclamate than when taking the placebo (4 and 4 versus 2 of the 6 nights); moreover, the average score was then statistically significantly higher (5.2 and 5.8 versus 3.3). It was concluded that there was a connection between the patient’s complaints of restless legs and the use of saccharine, but not the use of cyclamate.

A 38-year-old man developed dysphagia, fever and marked trismus, resulting in an abcess of the parafaryngeal region, soon after the surgical extraction of 2 mandibular molars. Despite systemic antibiotics and surgical drainage, the abcess spread to the mediastinum. Within a short space of time, cervical fasciitis necroticans and descending necrotizing mediastinitis developed. Because of the life-threatening health condition, the patient was admitted to a hospital for further treatment. He underwent surgical exploration of the cervical and sternal region, thoracotomy for mediastinal drainage, debridement, and daily mediastinal rinsing with hydrogen peroxide and betadine iodine. After 5 weeks intensive treatment, the patient could be discharged from the hospital in a fairly good condition of health.

Dental practitioners are supposed to have some knowledge of skin diseases, particularly those occurring in the face. They should encourage a patient to see his physician or a dermatologist for further evaluation and possible treatment. Diseases of the skin can be classified in various ways. In this overview, diseases are classified as infectious diseases, inflammatory diseases, autoimmune diseases, benign neoplasms, premalignant lesions, and malignant lesions. In the Dutch health care system, family doctors play an important role and, until recently, they have been the obvious persons to whom a patient with a detected skin disease was referred by dental practitioners. The general practitioner then determined whether a referral to a dermatologist was indicated. However, because of changes in the health care system it has become possible for a dentist to refer patients directly to a dermatologist in case of the presence of a skin disease.