Incompetent minors, insane persons, and all those who are prohibited to conclude contracts by law cannot enter into contracts. This means that the consent is required from the parent or guardian. Certain minors, intellectually and physically mature, can take decisions in relation with their health, especially if there are no major risks involved, which is almost always the case in the dentistry. This means that for young people under the age of 15 the consent of the parents or guardian must be obtained. Young people often come to the dentist alone with a dental problem. The dentist should in that case contact the parents in order to obtain consent, unless the children have a written consent of the parents. That is a very unreasonable and impractical situation, which in practice is difficult to apply. A young person who is in pain has a right to treatment, and the dentist who should not treat it would be guilty of failure to treat a person in distress. For this reason, it seems logical that in such a case, the treatment should be limited to the problem for which the child consults the dentist and further treatments will be postponed until a consent from the parents is obtained.

Sometimes necessary interventions cannot be performed if the parents do not consent to the treatment. That would be the case with orthodontic treatments. If the orthodontic treatment can be postponed to the moment that the child can give a valid consent (18 years in Belgium), there is not a big problem. If such a treatment will not be possible anymore or with a less favorable outcome, it is in principle possible that a child seeks the assistance of the Public Prosecutor who can send the case to the juvenile court in order to get a court decision. That is very exceptional but not impossible.

Another problem that arises with children is that consent, in case of divorce of the parents, shall be obtained from the parent who has the right of custody, except in emergency situations.

The subject of the contract is the commitment to give, to do or not to do something. Only things that are on the market can be the subject of agreements.

A cause is not valid if it is prohibited by law or contrary to public order or public morals. Dental surgery is allowed if it is necessary and therapeutic. What about pure cosmetic or esthetic treatments? Do they have a therapeutic value? Do we have to take only in consideration the physical or functional values? This can be disputed. A human being is concerned not only about physical but also about psychological well-being.

The problem of a patient suffering from an inferiority complex because of strong discolored teeth as a result of tetracyclines or due to heavily filled teeth can only be resolved with porcelain or acrylic veneers.

We can imagine that an intervention is unlawful if the risks of surgery are not in proportion with the therapeutic effects.

A patient has the right to interrupt a treatment unilaterally at any time. This may seem a contradiction at first sight, but it is not because agreements which cover the physical integrity are always revocable.

The revoking of the consent is therefore not a contractual error and does not give rise to damages.

A dentist can also step out of a treatment contract on condition that the health of the patient is not at risk and that he shall ensure that the continuity of the treatment will be guaranteed.

The dental contract is an agreement intuïtu personae, which means that a dentist should carry out the agreed treatment himself and not delegate the treatment without the consent of the patient.

The agreement is automatically terminated by the death of the dentist.

When something goes wrong during treatment and causes damage and if there is a causal relation between the fault and the damage, liability is possible.

The patient has the burden of proof and that is not always easy. He often does not even know that an error was made, and sometimes the damage appears many years after the treatment.

Each patient may expect that his/her dentist is competent, skilled, and experienced in the field of dentistry. This distinguishes him/her from the ordinary man who does not have these skills. He should not be world champion or the best specialist in that field of dentistry, but someone who meets the normal standards of good practice.

The standard of care is measured through objective, external, and impersonal criteria and compared with the behavior of a standard dentist with the same qualifications under the same circumstances.¹ It does not take into account subjective data such as age, sex, intelligence, and character. A dentist must be aware of his/her limits, and if he has no sufficient basic knowledge to perform a certain treatment, it is appropriate to refer the patient to a specialist or another colleague or to first acquire the specific technique. A dentist who performs a surgery which belongs to a recognized specialization in dentistry will be assessed according to the standard of care of that specialty. In Belgium there are two dental specialties recognized: orthodontics and periodontology. Since a general dentist received during his/her training the basic knowledge of orthodontics and periodontology, he may also exercise these subareas of dentistry on the condition that he meets the standards of care that are required for these specialties. A general dentist who performs endodontic or prosthetic treatments will not be compared with the dentists who followed additional training in this area of dentistry at the universities (which are not (yet) been officially recognized as a specialty) but with the standard general dentist. A lack of experience cannot be relied upon as a defense if something goes wrong. That means that a newly graduated dental professional or just starting up specialist must fulfill the same standards as his/her colleagues nor can an older dentist rely on the fact that he did not kept up with new treatment techniques.

That standard of care is not determined by the dental profession. It will be the privilege of the judge to decide what a dentist ought to do.

A dentist, who has to appear before court in a case where an endodontic file was swallowed, cannot argue that a rubber dam is not widely used in the region (country) where he practices.

The judge will take into account certain circumstances of time and place. That can be when a dentist performs an extraction on a bedridden patient without the necessary infrastructure (difficult circumstances, no accurate lightning) or when the treatment is urgent and life threatening.

The court will take into account the acquirements of science at the time of the surgery. The court will never rely on new scientific insights that were published after the disputed intervention.

The problem with dental and medical treatments is to determine if we are dealing with a fault or a complication and that is not always obvious.

Complications can be linked to the patient, the treatment, or the practitioner.

A patient can be allergic for some products (chrome-cobalt or adrenaline).

There are always risks that are inherent to the treatment. If adrenaline enters a blood vessel during injection of the local anesthetic, he may get tachycardia or syncope. This has no serious consequences for a healthy patient, but might have damaging consequences for a patient with a hidden or existing heart disease.

Practitioner-related complications are mostly the consequence of a lack of experience or incompetence, and in these cases we have to think more in terms of fault.

A judge will decide a case based on the provided evidence if a fault has been made.

In some cases, the burden of proof will be facilitated if the judge has a strong suspicion, deduced from known facts, that a fault has been committed. In that case, the burden of proof will shift to the practitioner.

A dead certainty is not necessary in civil cases, and a judicial certainty is enough (that means that there is such a strong degree of certainty that the judge does not have to consider the opposite anymore, even if it is still theoretical possible).

A dentist who recognizes that he committed a fault during treatment does not recognize liability. A dentist must deal honestly with his/her patient and inform him/her when something went wrong during treatment.

Recognizing liability by the practitioner should be avoided, even if that recognition does not bind the insurer. The patient has still the burden of proof, and he will only get compensation for damages from the insurer when he succeeds.

The prescription period of a medical error has a double limitation period: the legal action expires at 5 years. It starts to run from the day following the date on which the injured party discovers that something went wrong. No claim for damages can be installed 20 years after the date of the committed error.

A typical treatment can be divided into several phases: the diagnosis and the medical history, the consent of the patient, the treatment itself, and the aftercare.