Retrospective investigation of the prevention and characteristics of ectopic eruption of the first permanent molar

Ectopic eruption of permanent first molars is a local eruption disorder that results in impaction of the crown of the primary second molar distal due to the abnormal mesioangular eruption angle of the tooth. The aim of the present study was to evaluate the prevalence, distribution, and characteristics of ectopically erupted first permanent molars in children admitted to Gaziantep University, Department of Pediatric Dentistry, and also the prognosis of the ectopic eruption depending on the resorption degree. This retrospective study was performed by examining panoramic radiographs of 7070 patients aged 5 to 12 years. The age and gender of the patients, the number and location of ectopic first permanent molars, bilateral or unilateral formation, degree of resorption of the distal roots of primary second molars, and prognosis of the process were evaluated. The ectopic eruption was categorized according to the degree of resorption of the distal roots of the primary molars at the initial assessment, and was categorized according to the reversible-irreversible types at the follow-up appointment. Descriptive statistics were given as numbers, percentages, mean and standard deviation. Data were statistically analyzed using chi-square tests. 221 ectopic permanent first molar teeth were detected in 144 of 7070 cases examined, and the prevalence was found to be 2%. The mean age of 144 patients, whose ages ranged from 5 to 12 years, was 8.04 years. Ectopic eruption was most common (48.63%) in patients aged 7-8 years(p<0.05). Ectopic eruptions were more common in females (58.3%) than males (41.7%), and this rate was statistically significant (p<0.05). Of the ectopic permanent first molars, 143 (64.70%) were detected in the maxilla and 78 (35.30%) in the mandible. It was observed that most of the ectopic permanent first molars (77.50%) with mild to moderate primary tooth distal root resorption were reversible and resolved spontaneously without the need for treatment. It was determined that ectopic permanent first molar teeth (22.50%) with severe and very severe primary tooth root resorption were irreversible and remained impacted. This relationship between the degree of resorption and the type of ectopic eruption was found to be statistically significant (p<0.05). It was concluded that the increase in the severity of deciduous root resorption may cause irreversible ectopic eruption. Early diagnosis and treatment of ectopic permanent first molars is of great importance in order to prevent premature loss of primary second molars resulting in malocclusion.