The mandibular third molar. Dentists' judgement in the removal of asymptomatic molars

Research output: ThesisDoctoral Thesis (compilation)


The aim was to study dentists' judgement on the removal of and on the development of pathology associated with asymptomatic mandibular third molars. Thirty general dental practitioners (GDPs) and 10 oral surgeons were asked to judge 36 molars with equal distribution of three cues: patient's age, angular position and degree of impaction of the molar. Rating on a VAS was found to be an appropriate method to analyse the need for removal of asymptomatic molars.

The number of molars proposed for removal varied between O and 26 for the GDPs and between 3 and 21 for the oral surgeons. There was no molar all judges agreed should be removed. There was a substantial variation between the individual GDP and oral surgeon concerning the relative weight they gave different diseases for the development of pathology. The GDPs, as a group, considered cyst formation and the oral surgeons pericoronitis to be the most influential pathological entity.

Regarding the influence of the cues on the judgement of the need for removal, there was also a considerable variation in the dentists' individual judgements. As a group, the GDPs differentiated between two age-groups, and the oral surgeons differentiated between three age-groups. GDPs estimated the need for removal to be highest for distoangular and lowest for vertical molars, whereas oral surgeons gave the highest priority to removal of vertical and distoangular molars and the lowest priority to horizontal and mesioangular molars. Molars partially covered by soft tissue were given the highest priority for removal by both groups of judges. The mean proportion of variation for six diseases explained by the cues was high.

Risk for molars of different angular positions and degrees of impaction was calculated from evidence in the literature. The risk, i.e. the odds ratio, for development of pathology was more than 22 times higher for molars partially covered by soft tissue compared with other degrees of impaction, and 5 to 12 times higher for distoangular molars compared with molars in other positions.


  • Kerstin Knutsson
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Dentistry


  • visual analogue scale, oral surgery, tooth extraction, third molar, linear models, judgment, Decision making, impacted tooth, Odontology, stomatology, Odontologi
Original languageEnglish
Awarding Institution
Supervisors/Assistant supervisor
  • [unknown], [unknown], Supervisor, External person
Award date1996 May 10
Print ISBNs91-628-2005-2
Publication statusPublished - 1996
Publication categoryResearch

Bibliographic note

Defence details Date: 1996-05-10 Time: 09:15 Place: Aulan, Tandvårdshögskolan, Malmö External reviewer(s) Name: [unknown], [unknown] Title: [unknown] Affiliation: [unknown] ---