J Korean Assoc Oral Maxillofac Surg.  2016 Oct;42(5):251-258. 10.5125/jkaoms.2016.42.5.251.

Which factors are associated with difficult surgical extraction of impacted lower third molars?

• Park KL

• KMID: 2356250
• DOI: http://doi.org/10.5125/jkaoms.2016.42.5.251

Abstract

OBJECTIVES
The aim of this retrospective study was to investigate factors associated with increased difficulty in the surgical extraction of impacted lower third molars and to improve identification of difficult cases.
MATERIALS AND METHODS
A total of 680 patients who required 762 surgical extractions of impacted lower third molars from 2009 to 2014 were enrolled in the study. Demographic factors, clinical factors, radiographic factors, surgical extraction difficulty, and presumed causes of difficulty were collected. Data were statistically analyzed using IBM SPSS Statistics version 23.
RESULTS
Age, sex, depth of impaction, and blurred radiographic image influenced difficulty in surgical extraction. The position of the impacted tooth influenced surgical difficulty, especially when it was accompanied by other factors.
CONCLUSION
It is challenging to design a reliable and practical instrument to predict difficulty in surgical extraction of impacted lower third molars. To identify very difficult cases, root investigation using computed tomography is advised when impacted tooth position suggests difficult extraction.

Keyword

Third molar; Mandible; Impaction; Tooth extraction; Difficulty

MeSH Terms

Demography
Humans
Mandible
Molar, Third*
Retrospective Studies
Tooth Extraction
Tooth, Impacted

Figure

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  Fig. 1 Difficulty group distribution in Pederson index.

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  Fig. 2 Two types of radiographic images. A. A panoramic image that shows blurred root image and indistinct border. B. A panoramic image that shows relatively clear root anatomy and sharp border.

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