Clinical and radiographic characteristics of pycnodysostosis: A systematic review

Abstract

Purpose: Pycnodysostosis (PYCD), an autosomal recessive syndrome, is characterized by an imbalance in bone remodeling that produces various clinical and radiographic craniofacial manifestations. This review represents a systematic examination of these manifestations, as well as oral features associated with PYCD.

Materials and methods: A systematic review was conducted across 8 databases from February to March 2023. The search strategy focused on studies reporting cases of PYCD that examined the clinical and radiographic craniofacial and oral characteristics associated with this syndrome.

Results: The review included 84 studies, encompassing a total of 179 cases of PYCD. More than half of the patients were female (55.3%), and the mean age was 14.7 years. Parental consanguinity was reported in 51.4% of the cases. The most common craniofacial clinical manifestation was a prominent nose, observed in 57.5% of cases. Radiographically, the most frequently reported craniofacial characteristics included the presence of an obtuse mandibular angle (84.3%) and frontal cranial bosses (82.1%). Clinical and radiographic examinations revealed oral alterations, with micrognathia present in 62.6% of patients and malocclusion in 59.2%. Among dental anomalies, tooth agenesis was the most commonly reported, affecting 15.6% of patients.

Conclusion: Understanding the clinical and radiographic craniofacial features of PYCD is crucial for dental professionals. This knowledge enables these clinicians to devise effective treatment plans and improve patient quality of life.

Keywords: Diagnostic Imaging; Maxillofacial Abnormalities; Pycnodysostosis; Syndrome.

Fig. 1. Flowchart illustrates the article selection process.

Fig. 2. Geographic distribution, by continent, of pycnodysostosis cases reported in the literature and included in this study.

Fig. 3. Frontal extraoral photograph (A) and profile extraoral photograph (B) of a patient diagnosed with pycnodysostosis, present with a prominent nose, micrognathia, retrognathia, hypoplasia of the middle third of the face, and brachydactyly (C).

Fig. 4. Discontinuity of the cranial vault is evident on cone-beam computed tomography coronal (A) and sagittal (B) reconstructions. C and D. Three-dimensional reconstruction images show open sutures and fontanelles, as well as frontal and parietal bosses.

Fig. 5. A. Intraoral photograph shows malocclusion and enamel hypoplasia. B. Intraoral photograph reveals intraoral fistula, which is compatible with the clinical diagnosis of osteomyelitis. C. Panoramic radiograph illustrates increased bone density, obtuse mandibular angle, missing teeth, and the presence of an osteolytic lesion in the body of the left mandible, accompanied by areas of bony sequestrum. D. Axial cone-beam computed tomographic images of the mandible depicts a hypodense line in the lingual mandibular cortex, compatible with a pathological fracture.