Craniofacial and oral alterations in patients with Neurofibromatosis 1

Abstract

Neurofibromatosis type 1 (NF1) is one of the most common inherited syndromes. The literature on craniofacial alterations associated with NF1 has been limited and partially contradictory. This review is based on literature search and the results of the clinical study "Craniofacial and Oral Alterations and Speech in patients with Neurofibromatosis 1", carried out at the University of Turku and Turku University Hospital, Finland in 2006-2012. By the end of 2012, a total of 110 NF1 patients, 54 female and 56 male patients, were examined.A part of our results confirms pre-existing understanding, a part is contradictory to previous considerations based mainly on case reports, and some are entirely novel. Specifically, our results confirmed that enlargement the mandibular canal is the most common abnormality of the mandible in patients with NF1. It should be noted, however, that this finding does not require treatment. Caries was not a major problem. In fact, it was less frequent in NF1 patients compared to reference population. These findings abrogate some previous perceptions. Novel findings of our project include periapical cemental dysplasia in females; short jaws, a finding which usually does not affect bite; and immunohistological analysis of oral mucosal abnormalities. Pioneering study on speech showed that various deviations were very common: As many as 94% of the participants showed some alterations.To conclude, the awareness of craniofacial alterations common in NF1would help avoiding unnecessary and even harmful involvement, e.g. of periapical cemental dysplasia or enlarged mandibular canal which do not require treatment.

Keywords: Craniofacial alteration; Dental age; Neurofibromatosis 1; Oral soft tissue; Periapical Cemental dysplasia; Speech; Tooth Developoment; Wide Mandibular Canal.

Fig. 1

Orthopantomogram and two intraoral radiographs (insets) of a 35-year-old woman with NF1 shows periradicular radiolucencies with intralesional calcification around vital teeth number 33 and 43 (arrows) suggesting the mature stage of periapical cemental dysplasia

Fig. 2

Orthopantomogram of a 55-year-old man with NF1. The mandibular canals (long arrows) on both sides of the mandible are widened in their full length and the mental foramen (short arrow) on the left side is enlarged. Note also the elongated right mandibular condyle (*)

Fig. 3

Lateral skull radiograph of a 53-year-old man with NF1 shows marked maxillary retrognatia

Fig. 4

A solitary mucosal neurofibroma (arrow) behind frontal teeth of lower jaw in a 58-year-old woman with NF1. Note also irregularities on both sides of the edge of the tongue arising suspicion of soft tissue overgrowth

Fig. 5

Mucosal neurofibroma (arrow) on dorsal tongue in 30-year-old woman with NF1