Ectopic eruption of the second premolar: an analysis of four different treatment approaches

  • M. Q. Ismail
  • E. Lauridsen
  • J. O. Andreasen
  • N. V. HermannEmail author
Original Scientific Article



Ectopic second premolars may lead to impaction and loss of space in the jaws, and in rare cases even to resorption of the first permanent molar. The aim of this study was to analyse different treatment strategies of ectopic second premolars and if possible give guidelines on when to favour different treatment approaches.

Materials and methods

The study was a retrospective, non-randomised, outcome analysis of treatment on 41 ectopic second premolars in 37 patients (24 females and 13 males). In all cases oral examination, radiographs (pre-, peri-, and post) and full medical history were obtained. The treatment options included: (a) spontaneous eruption, (b) spontaneous eruption + extraction of primary tooth, (c) surgical exposure, (d) surgical uprighting, and (e) surgical uprighting + orthodontic extrusion. For evaluation each tooth was scored according to: (1) stage of root development, (2) distance between edges of the premolar and first permanent molar, (3) depth of impaction, (4) inclination, (5) horizontal position of the tooth. The level of significance was set to 5%.


Only mild cases of ectopic second premolars are self-correcting. Based on the position of the tooth in the jaw different treatment options may be chosen, these may include: extraction of primary predecessor (impaction depth < 5 mm, inclination < 55°), surgical exposure of tooth germ (impaction depth < 5.5 mm, inclination < 95°) or surgical uprighting (impaction depth > 5.5 mm with no inclination limit).


If there is no sign of self-correction after a short observation period, it is important to consider active treatment to help guiding the tooth into the correct eruption pathway.


Ectopy Impaction Eruption Second premolar Surgical exposure Surgical uprighting 


Compliance with ethical standards

Conflict of interest

The authors have no disclosures.

Research involving human participants and/or animals

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© European Academy of Paediatric Dentistry 2019

Authors and Affiliations

  1. 1.Department of Pediatric Dentistry and Clinical Genetics, School of Dentistry, Faculty of Health SciencesUniversity of CopenhagenCopenhagen NDenmark
  2. 2.Resource Centre for Rare Oral DiseasesCopenhagen University Hospital RigshospitaletCopenhagen ØDenmark

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