Spontaneous eruption of an impacted mandibular first molar with root development at Nolla stage 9 after removal of the odontoma: a case report

Background: A mandibular first molar impaction is relatively rare. Several factors contribute to first molar impaction, including inadequate space in the dental arch, mechanical obstructions like supernumerary teeth or odontomas, eruption mechanism disruptions and idiopathic causes. Clinical scenarios offer a range of treatment options, such as observation, surgical exposure, orthodontic traction or extraction. Case: In this case, a mandibular first molar was impacted beneath a large odontoma. Located near the lower border of the mandible, this impacted molar exhibits a distally curved and notably shortened root with root development at Nolla stage 9. A surgically removed odontoma resulted in spontaneous eruption of the impacted first molar and normal occlusion without orthodontic traction. Further, the impacted tooth’s root length gradually increased until it was comparable to the contralateral molar’s. Conclusions: In this situation, observation with the intention of waiting for spontaneous eruption after obstructions have been removed is an optional treatment approach if the impacted tooth is enclosed by a dental follicle and is erupting in the correct direction.

Impacted mandibular first molar; Nolla stage 9; Odontoma; Spontaneous eruption

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