Differentiation Between Dental Follicle and Dentigerous Cyst in Impacted Mandibular Third Molars: A Prospective Cohort Study.

BACKGROUND

Impacted mandibular third molars may be associated with pericoronal tissues that can undergo cystic transformation. Distinguishing dental follicles (DFs) from dentigerous cysts (DCs) based solely on radiographic findings is often unreliable, highlighting the importance of histopathological evaluation for accurate diagnosis and management.

PURPOSE: The study purpose was to measure the association between radiographic and demographic variables and histologic diagnosis among patients with impacted third molars.

STUDY

DESIGN

In this single-center prospective cohort study, the investigators analyzed data from subjects who underwent mandibular third molar removal between 2010 and 2011 at Ondokuz Mayıs University. Inclusion criteria were fully bone-retained impacted mandibular third molars with histopathologic confirmation of epithelial tissue and age ≥16 years. Subjects with partially erupted teeth, non-DC pathologies, or systemic contraindications to surgery were excluded.

INDEPENDENT VARIABLES: The independent variable was a set of radiographic findings, including follicular width and tooth position.

MAIN OUTCOME VARIABLES: The outcome variable was histologic diagnosis, categorized as DF or DC.

COVARIATES: Covariates included age and sex.

ANALYSIS: Bivariate associations were evaluated using relative risks (RRs) with 95% CIs. Multivariable logistic regression assessed independent predictors of DC.

RESULTS

The sample consisted of 250 subjects with a mean age of 22.4 years (SD 2.5); 178 (71.2%) were female. Histologic examination revealed 111 (44.4%) DFs and 139 (55.6%) DCs. Lesions with a radiographic width ≥2.5 mm (33.6% of cases) were associated with DC (RR = 1.79; 95% CI, 1.46 to 2.19; P < .001). Compared with mesioangular impactions, vertical (RR = 2.62; 95% CI, 1.98 to 3.48), horizontal (RR = 2.12; 95% CI, 1.50 to 3.00), and distoangular positions (RR = 2.89; 95% CI, 2.10 to 4.00) were also associated with DC (all P < .001). Subjects in the third decade demonstrated an increased risk of DC compared with those in the second decade (RR = 1.95; 95% CI, 1.41 to 2.70; P < .001), whereas sex was not associated with histologic diagnosis (RR = 1.11; 95% CI, 0.88 to 1.40; P = .37).

CONCLUSION AND RELEVANCE: The absence of clinical symptoms does not exclude radiographic findings indicative of pathological changes in impacted third molars. Increased follicular width and tooth position were associated with DC, supporting integrated clinical, radiographic, and histopathological evaluation.