Removal of Third Molars National Institutes of Health
Consensus Development Conference Statement
November 28-30, 1979
This statement is more than five years old and is provided solely for historical purposes. Due to the cumulative nature of medical research, new knowledge has inevitably accumulated in this subject area in the time since the statement was initially prepared. Thus some of the material is likely to be out of date, and at worst simply wrong. For reliable, current information on this and other health topics, we recommend consulting the National Institutes of Health's MedlinePlus http://www.nlm.nih.gov/medlineplus/.
This statement was originally published as: Removal of Third Molars. NIH Consens Statement 1979 Nov 28-30;2(11):65-68.For making bibliographic reference to the statement in the electronic form displayed here, it is recommended that the following format be used: Removal of Third Molars. NIH Consens Statement Online 1979 Nov 28-30 [cited year month day];2(11):65-68.
A consensus development conference on Removal of Third Molars was held at the National Institutes of Health on November 28-3O, 1979. More than 200 practicing dentists and scientists, representing all disciplines within the profession, met in an effort to reach general agreement on when and under what circumstances third molar extraction is advised and to identify areas where further research is needed.
The conference was sponsored by the National Institute of Dental Research, National Institutes of Health. The NIH consensus development program brings together biomedical researchers, practicing dentists and physicians, consumers, and others, as appropriate, in an effort to arrive at general agreement on the efficacy and safety of medical and dental technologies and procedures.
The conference participants divided into five workshops to explore the following issues:
- the effect of third molar removal on growth and development;
- the timing and technical considerations for third molar removal;
- prosthodontic and periodontic considerations for third molar removal;
- the morbidity of third molar removal; and
- the advantages and disadvantages of third molar removal.
The workshop reports were presented and discussed by all participants on the final day and formed the basis for areas of consensus.
The Effect of Third Molar Removal on Growth and Development
Although there are cogent orthodontic reasons for early removal of third molars, the group felt that the suggested practice of enucleation of third molar buds, based on predictive studies at age 7 to 9, is not currently acceptable. The workshop concluded that, based on current research with longitudinal records, present predictive techniques for third molar eruption or impaction are not highly reliable, are overly simplistic, and should be used with caution. Another important decision of the workshop participants was that, in some patients, unerupted third molars should be removed before starting maxillary retraction procedures which would result in their impaction. Finally, it was agreed that there is little rationale, based on present evidence, for the extraction of third molars solely to minimize present or future crowding of lower anterior teeth, either in orthodontic or nonorthodontic patients.
The Timing and Technical Considerations for Third Molar Removal
There was agreement that postoperative pain, swelling, infection and other possible consequences of surgery are minimized in patients who are dentally young, as judged by the third molar roots being about two-thirds developed. An additional consideration relates to some evidence which suggests that early removal of the third molar has a beneficial effect on the periodontal health of the second molar. The workshop agreed that it is necessary to instruct the student and practitioner in recognizing the need for early removal of third molars in those instances where extraction is definitely indicated.
In assessing surgical risk and morbidity related to technique the workshop concluded that age itself is not a risk factor in patients judged healthy by the American Society of Anesthesiology classification system. The incidence of systemic disease increases with age, however, and post-surgical morbidity, both local and systemic, are age-related. Morbidity is minimized by careful surgical techniques, but clinical trials of variations in surgical protocols have not been done and should be initiated.
The workshop also identified several other areas of insufficient knowledge related to management of third molars and suggested that they should also be subjects of research. Some of these are: the relation of third molars to crowding of the dentition; the psychological effect of third molar surgery at various ages; the relative cost to the patient of early versus late third molar removal, including monetary investment and personal discomfort; and the effectiveness of adjunctive therapy such as steroids and antibiotics in reducing the morbidity of third molar surgery.
A final subject addressed by this workshop was the economic implications of third molar retention versus prophylactic removal at an early age. The group recognized the need to consider the cost to the patient and society of third molar surgery. However, the topic of cost could not be studied extensively within the context of this conference and it was suggested that it should be carefully analyzed in a separate, carefully planned study.
Prosthodontic and Periodontic Considerations for Third Molar Removal
The workshop recommended that fully-impacted third molars should be removed when there is evidence of pathological changes, as should partially impacted ones when there is evidence of irreversible pathology. Erupted third molars, which can be maintained in a state of health, should be retained for their potential usefulness as abutment teeth and for maintaining vertical dimension. The workshop also identified as an area for investigation the relative risk and/or benefit of retaining or delaying removal of impacted third molars for future prosthodontic use.
The workshop further recommended that both short- and long-term studies be undertaken in a number of areas related to periodontal considerations. Some of them are: variations of flap design and bone removal in third molar surgery and their effect upon the periodontal status of the adjacent second molar; the periodontal state of the second molar in situations of long-term third molar presence; the incidence of second molar root resorption due to an adjacent third molar; and the susceptibility of an erupted third molar to periodontal disease in comparison to other teeth.
The Morbidity of Third Molar Removal
The workshop recommended that patients should be informed of potential surgical risks, including any permanent condition that has an incidence greater than 0.5% or any transitory condition that occurs with an incidence of 5% or more. On this basis, available data indicate that for routine cases, patients should be informed about hemorrhage, pain, swelling, alveolar osteitis, trismus, and nerve injury. With unusual cases, other detailed statements should be made to the patient regarding morbidity.
There was also consensus that, where indicated, third molars should be removed in the younger aged patient because there is less transitory or permanent morbidity. After lengthy discussion, it was also agreed that impaction or malposition of a third molar is an abnormal state and may justify its removal. Such treatment is not considered "prophylactic." Finally, the workshop advised that further research be undertaken to study, prospectively, the incidence of preoperative, intraoperative, and postoperative morbidity in third molar surgery and its relationship to age. Other suggested research areas involve therapeutic approaches to the prevention or control of pain, swelling, trismus, infection, and hemorrhage.
The Advantages and Disadvantages of Third Molar Removal
This workshop concluded that third molars, whether impacted or erupted, with evidence of follicular enlargement should be removed and the associated soft tissue should be submitted for microscopic examination. Impacted teeth that develop soft tissue inflammatory conditions (pericoronitis) should also be removed because of their known potential for repetitive infection and morbidity. The workshop recognized, however, that the incidence and recurrence rate of pericoronitis has not been studied and is deserving of prospective investigation.
Although there was no consensus on the subject of removal of asymptomatic impacted teeth with no evidence of pathology, it was agreed that long-range studies of the subject are needed. Consensus was reached that third molars with nonrestorable carious lesions and third molars contributing to resorption of adjacent teeth should be removed.
Finally, there was some concern about the inadequacy of intra-oral radiographs, particularly bite-wings, in assessing third molars. It was decided that the absence of a third molar on a routine dental film, without a history of prior extraction, demands more extensive radiographic examination.
The conference participants carefully examined the long-established practice of third molar removal. A number of clinical procedures were endorsed; others were controversial but identified as subjects for additional research. A number of well-defined criteria for the removal of third molars emerged. They are, in part, infection, nonrestorable carious lesions, cysts, tumors, and destruction of adjacent teeth and bone. There is less morbidity associated with removal of these teeth in the young than in the older patient.
The effectiveness of removal of third molars to prevent crowding of lower incisors is not borne out by the studies currently available. Third molar bud removal in youngsters, based on predictive studies, is not currently an acceptable practice in view of available knowledge.
Clinical experience suggests that morbidity and serious complications may be reduced if impacted teeth are removed at an early age. The observation is not disputed by available data, but there is enough question about the life-cycle of impacted third molars to suggest the need for well-designed prospective studies of the subject.
Consensus Development Panel
Dr. Walter C. Guralnick (Co-chairman)
Harvard School of Dental Medicine
Dr. Daniel M. Laskin (Co-chairman)
College of Dentistry
University of Illinois
Dr. Robert Bruce
Dr. Thomas M. Graber
Dr. James Kelly
Dr. William R. Laney
Dr. Gilbert Lilly
Iowa City, Iowa
Dr. Alan M. Poison
Rochester, New York.
National Institute of Dental Research
Office of Medical Applications of Research