Opinions of American and Swedish orthodontists about the role of erupting third molars as a cause of dental crowding.
OBJECTIVE
To compare the opinions of Swedish orthodontists and American orthodontists regarding the association between third molar eruption and dental crowding.


METHODS
A survey was distributed to Swedish orthodontists (n = 230) asking their views on the force exerted by erupting third molars, its relationship to crowding, and their recommendations for prophylactic removal. Results were compared with those from a similar study conducted in the United States. Chi square analysis was used to determine differences in responses to questions between Swedish and American orthodontists. P < or = .05 was considered significant.


RESULTS
Both Swedish and American orthodontists believed that lower third molars were more likely than upper third molars to cause force (65% and 58% for Swedish and American orthodontists, respectively) and crowding (42% and 40%, respectively). No statistically significant differences were seen between the answers of American and Swedish orthodontists regarding the role of upper and lower third molars in causing crowding. Although only 18% of Swedish orthodontists "generally" or "sometimes" recommended prophylactic removal of mandibular third molars, 36% of American orthodontists "generally" or "sometimes" recommended removal (P < .0001).


CONCLUSIONS
Most orthodontists in the United States and Sweden do believe that erupting lower third molars exert an anterior force; however, they also believe that these teeth "rarely" or "never" cause crowding of the dentition. The reason that more American orthodontists recommend prophylactic removal of mandibular third molars remains unexplained.
Department of Orthodontics, School of Dentistry, Virginia Commonwealth University, Richmond, VA, USA. etufekci@vcu.edu
E
E
Tüfekçi
D
D
Svensk
J
J
Kallunki
J
J
Huggare
S J
SJ
Lindauer
D M
DM
Laskin
D001291:Attitude of Health Personnel; D001696:Biomechanical Phenomena; D003815:Dentists / Q000523:psychology*; D006801:Humans; D008310:Malocclusion / Q000209:etiology* / Q000517:prevention & control; D008334:Mandible; D008437:Maxilla; D008964:Molar, Third / Q000503:physiopathology* / Q000601:surgery; D009970:Orthodontics; D013314:Stress, Mechanical; D013548:Sweden; D014078:Tooth Eruption / Q000502:physiology*; D014081:Tooth Extraction; D014481:United States