Introduction: Primary failure of eruption (PFE) can be defined as the partial or complete failure of eruption of at least one posterior tooth, without any mechanical obstacle; isolated and syndromic forms exist. PFE results from an abnormal dental eruption process that can affect temporary teeth and / or permanent teeth. Molars are the main affected teeth, inducing posterior infraclusions. Orthodontists are the specialists most often concerned by this rare pathology. Unsuccessful orthodontic-surgical traction therapies are commonly reported. Materials and Methods: The aim of our study using a prospective survey was to evaluate the level of knowledge reported by the orthodontists and the therapeutic difficulties they reported. An anonymous questionnaire was submitted to practitioners practicing in north-eastern France (Grand Est and Bourgogne-Franche-Comté regions). Results: The participation rate was 33.5%. In France, until 2015, specialization in orthodontics was obtained thanks to a local qualification, the Certificat d’Etudes Cliniques Spéciales – Mention Orthodontie (CECSMO), which has now been replaced by specialization following a national ranking competition. Most respondents obtained their qualification between 1980 and 2009 (80%), via the CECSMO (87%). Eighty-six per cent were aware of PFE but only 20% of them knew that PTHR1 (Parathyroid Hormone Receptor 1) gene could be involved in this pathology. The wide range of proposed therapies and the variable satisfaction rates highlight the difficulties encountered by practitioners. Discussion: Phenotypic variability complicates the diagnosis and makes any therapeutic systematization uncertain. Conclusion: New clinical research projects, particularly in the field of molecular diagnosis, may improve understanding of genotype-phenotype correlations, and may potentially pilot therapeutic management.