Orthodontic and surgical management of cleidocranial dysplasia
A 14-year-old Caucasian girl diagnosed with CCD presented for orthodontic treatment with a desire to have greater number of teeth to be visible. Her mother and younger sister also had CCD. Her medical and surgical histories revealed mitral valve prolapse, tethered spinal cord, arthritis, Crohn's disease, thyroid reduction surgery, tonsillectomy, and Z-plasty of the lingual frenulum. The initial evaluation revealed jaw pain, bilateral temporomandibular joint clicking, and facial muscle pain. Mouth breathing, tongue thrusting, and clenching habits were also noted.\nThe patient had a concave facial profile and decreased facial height due to maxillary underdevelopment. Her lips were retrusive, resulting in an edentulous appearance (). The intraoral examination showed that she had five retained primary teeth (i.e., 55, 63, 75, 74, and 73) and 15 fully erupted permanent teeth (). She had a negative sagittal jaw relationship with class III malocclusion due to the hypoplastic maxilla (). On the panoramic radiograph, 14 impacted permanent teeth were identified and the left mandibular second molar was determined to be congenitally missing (). The lateral cephalogram confirmed maxillary hypoplasia (). Multiple impacted supernumerary teeth had been extracted 2 years earlier along with the mandibular right first molar, due to extensive caries.\nOrthodontic treatment was initiated with the following objectives: maxillary expansion, removal of the retained primary and supernumerary teeth, guided eruption or extrusion of the impacted permanent teeth, and correction of the class III jaw relationship by maxillary advancement surgery.\nA hyrax expander was placed for 2 months, which achieved 11 mm of expansion (). Heavy upper and lower wires were placed; the retained primary teeth were removed; and impacted permanent teeth 11, 15, 21, 22, 23, 35, and 47 were surgically exposed and bonded with gold chains placed close to the cusp tips for guided eruption (). All the bonded teeth except 21 erupted after approximately 11 months. The maxillary left central incisor was extracted because of exposure of the root, which was very short.\nOrthodontic alignment and coordination of the dental arches were complete in 14 months (). Le Fort I osteotomy was performed at age 18 (). With the removal of the remaining orthodontic appliances and placement of an implant and a fixed prosthesis for the maxillary left central incisor, the treatment was completed (). However, the patient's poor oral hygiene during the retention stage led to complete loss of the maxillary dentition.\nAlthough no post treatment extraoral and intraoral photographs were obtainable, because of the loss of the maxillary teeth, the Dolphin software was used to digitize and superimpose the pretreatment and postsurgical lateral cephalograms (). Comparison of the ANB and overjet values between these time points indicated improvement in the sagittal jaw relationship after the maxillary advancement surgery and orthodontic treatment (). The overbite also improved significantly, from -6.7 mm to 0.1 mm\nWe reviewed our database (FileMaker Pro 10.0 V3; FileMaker Inc., Santa Clara, CA, USA) of all the individuals with CCD who had been diagnosed at the UCSF. summarizes their clinical features.\nSeventeen (nine female and eight male) affected individuals were identified. Four of 15 individuals (the height of two individuals was not recorded) had short stature. Further, 57% had a family history of CCD, with one-to-three generations of CCD passed down in the family. Eight of the 17 individuals had vertebral changes such as scoliosis. The characteristic features of this condition, such as missing or hypoplastic clavicles, persistent metopic sutures, frontal bossing, and hypertelorism, were observed in 93%, 94%, 88%, and 69% of these subjects, respectively. A high incidence of otitis media that required surgery to place pressure-equalization tubes was noted. Seven patients had speech problems and received speech therapy ().\nRegarding the dental features, congenital hypodontia was observed in 12% of this population. The number of retained primary teeth ranged from 0 to 20, with the mandibular canine being the most frequently retained primary tooth (). On average, the mandibular primary teeth were slightly more likely to be retained than the maxillary ones. The number of impacted permanent teeth ranged from 3 to 27, with the incisors and canines being the most frequently impacted in the maxillary and mandibular arches, respectively (). Zero to 18 supernumerary teeth were observed.\nNoteworthily, 14 of the 17 subjects had maxillary hypoplasia, 88% had class III malocclusion due to the hypoplastic maxilla, and 10 patients required Le Fort I maxillary advancement surgery.