Restoration of a vertical alveolar bone defect by orthodontic relocation of a mesially impacted mandibular first molar

• Alveolar bone defect has to be assessed before making an extraction decision.
• Orthodontic eruption can recover an infrabony defect caused by an impacted tooth.
• A miniscrew is a valuable tool for therapeutic diagnosis of possible ankylosis.

An impacted mandibular first molar tends to cause serious bone defects of the adjacent teeth. When choosing between the 2 typical treatment options—extraction or orthodontic relocation of the impacted tooth—the decision should be based on assessment of the prognosis. A 22-year-old man with severe mesioangulation and impaction of the mandibular first molar and a related vertical bone defect on the distal side of the second premolar was treated with extraction of the second molar and orthodontic relocation of the first molar with a retromolar miniscrew. Comprehensive orthodontic treatment involving premolar extraction was conducted. Strategic extraction of the molar and adequate orthodontic movement helped to restore the bone structure on the affected side. This case report suggests the effectiveness of restoration of bone defects by using viable periodontal tissues around the impacted tooth for the longevity of the periodontium.