The Primary Failure of Eruption in orthodontics: knowledge to prevent overtreatment

OBJECTIVES The aim of this paper is to report a rare clinical case of Primary Failure of Eruption (PFE) in a young Italian patient. MATERIALS AND METHODS A 19-year-old patient presented a bilateral posterior dental open bite with lingual interposition during swallowing that was not resolved with a previous four-years orthodontic treatment with fixed appliance. The diagnostic hypothesis of Primary Failure of Eruption emerged, so a genetic analysis with molecular analysis of the PTH1R gene was required. The analysis showed het-erozygosity in the sequence variant c.322-322deIT (p.C108Vfs*82), that is associated with Primary Failure of Eruption. This finding confirmed the diagnosis of Primary Failure of Eruption. The patient was finally referred to a maxillofacial surgeon for the evaluation of the most appropriate treatment of her clinical condition, as teeth affected by Primary Failure of Eruption cannot be moved with orthodontic treatment. RESULTS AND DISCUSSION As in patients with Primary Failure of Eruption an orthodontic treatment with teeth extrusion can cause their ankylosis, in the case presented it emerged the hypothesis that the previous orthodontic treatment might have promoted this process and that, therefore, it could have been performed because Primary Failure of Eruption has probably not have been suspected at the time of treatment begin. By considering the patient’s age, the level of infraocclusion and posterior open bite, and by sus-pecting the dental ankylosis of the infraoccluded teeth, the clinicians decided to refer the patient to a maxillofacial surgeon for the evaluation of the most appropriate therapeutic option for the management of the case. CONCLUSIONS Primary Failure of Eruption should be suspected if a bilateral infraoc-clusion or ankylosis of the teeth causing open bite is present, in order to avoid an orthodontic treatment which could lead to dental ankylosis. CLINICAL SIGNIFICANCE The authors of this paper wanted to contribute to spread the knowledge of a rare clinical condition repre-sented by Primary Failure of Erup-tion. They aimed to put the attention on the importance of a correct differential diagnosis with other simi-lar conditions in terms of clinical manifestations and on requiring a genetic analysis if a diagnostic sus-pect of Primary Failure of Eruption emerged. This is necessary in order to perform the most adequate treatment for the affected patient.