Pycnodysostosis with Special Emphasis on Dentofacial Characteristics

Pycnodysostosis: Characteristics of teeth, mouth and jaws

OBJECTIVES

To describe the clinical and radiographic oro-dental characteristics of patients with pycnodysostosis (PDO).

MATERIALS & METHODS

A short interview and clinical examination of seven patients with PDO were performed as well as assessment of the temporomandibular joints and masticatory muscles using the diagnostic criteria for temporomandibular disorders, DC-TMD form. A full set of records were taken including photos and intraoral scan. Finally, existing cone beam computed tomography (CBCT) images and radiographs were also studied.

RESULTS

All patients presented with bimaxillary micrognathia, five had a convex profile, and two had a straight profile. In addition, posterior open bite, Angle Class III molar relation with accompanying anterior crossbite and a grooved median palate were common findings. No patient showed symptoms of temporomandibular disorder (TMD) apart from some clicking. Finally, the main radiographic findings were the obtuse mandibular angle, the frontal bossing, the elongation of the coronoid/condylar process and the presence of hypercementosis with obliterated pulp chambers.

CONCLUSION

The examined patients with PDO were characterized by dental crowding, malocclusion (anterior crossbite, posterior open bite), hypercementosis, obliterated pulp chambers and deviations in mandibular morphology. In conclusion, patients with PDO have a specific need for dental and orthodontic monitoring with focus on crowding and posterior open bite. The patients will benefit from a long-term orthodontic plan including extractions.

Clinico-Radiological Perspectives of Pycnodysostosis - A Rare Case Series

Pycnodysostosis is an inherited autosomal recessive disorder characterized by dysplasia of the skeletal system. It occurs in any human races with no disparity in gender or age predilection. The disease is diagnosed at a young age owing to the frequent fragile bone fractures. Craniofacial and dental manifestations may overlap with those of other craniofacial dysostosis; therefore, precise knowledge is essential in differential diagnosis as it may affect the treatment outcome. Here, we report three cases with typical clinical and radiological features, among which one presented with osteomyelitis of the mandible.

Clinical and radiographic characteristics of pycnodysostosis: A systematic review

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.

Evaluation of Clinical Characteristics and Growth Hormone Response in a Rare Skeletal Dysplasia: Pycnodysostosis

Introduction Pycnodysostosis is a rare osteosclerotic skeletal dysplasia; its clinical features include short stature, characteristic facial features, increased bone fragility, and acro-osteolysis of the distal phalanx. Lack of clear guidelines for treatment and follow-up in rare diseases such as pycnodysostosis with growth hormone (GH) deficiency poses a difficulty for the clinician. This study aims to identify clinical, radiological, and endocrine findings of patients with pycnodysostosis focusing on the first year of recombinant human growth hormone (rhGH) treatment response. The eminence of this study is that it presents clinical experience with rhGH, providing an approach for future similar cases. Methods Three girls and two boys from three different families diagnosed with pycnodysostosis via clinical, radiological, and genetic evaluation followed up in the pediatric endocrinology clinic between 2022 and 2023 were enrolled in this study. Clinical findings, anthropometric measurements (weight, height, body mass index [BMI]), and laboratory, radiological, and genetic examinations were evaluated retrospectively. Participants were evaluated for GH deficiency using L-DOPA and clonidine tests if growth rate was below -2 standard deviation score (SDS) for gender and age after one-year follow-up. Results Complaints on admission were short stature (80%) and recurrent bone fractures (20%). Characteristic facial features and brachydactyly were seen in all the patients. Median height SDS on admission was -3.0 (range: -1.9 to -3.8). Median height SDS on last clinic visit was -3.2 (range: -1.7 to -4.2) at a median age of 8 years (range: 3.5-14 years). BMI was normal in four patients, while one was overweight. Bone mineral densitometry z-score was high, and two patients had bone fractures following minor trauma, while one had recurrent fractures. Two siblings (first and second cases) and the third case were diagnosed with GH deficiency, and anterior pituitary hormones were normal otherwise. One had partial empty sella in hypophyseal magnetic resonance imaging. rhGH (33 mcg/kg/day, subcutaneously) was started. Growth rate of the first, second, and third cases increased from 3.3, 3.1, 3.9 to 5, 4.3, 7.2 cm/year, respectively. Prior to rhGH, two had adenoid hypertrophy which was stable following rhGH. Growth rate follow-up of the fourth case continues, while the fifth case, the only participant who has reached adult height, has normal height according to age and gender normative. Conclusion Although rare, pycnodysostosis should not be overlooked in a patient with characteristic facial features, disproportionate short stature, and recurrent fractures. GH deficiency should be evaluated early if growth rate is declining. rhGH may restore growth rate and the possibility of catch-up in growth in patients with pycnodysostosis and GH deficiency. Hence, after first year of rhGH, growth rate of patients with pycnodysostosis is lower when compared to other etiologies of GH deficiency.

Surgical treatment of pycnodysostosis associated with pathological tibial fracture : Case report and review of the literature

BACKGROUND

Pycnodysostosis is a rare autosomal recessive lysosomal disorder of bone characterized by diffuse skeletal condensation with thickening of the cortex and narrowing of the medullary canal.

CASE PRESENTATION

We present the case of a 4-year-old girl diagnosed with pycnodysostosis and associated pathological tibial fracture. The tibia had an absence of medullary canal. Surgery included reduction and reaming of the canal with placement of a 5 mm diameter telescopic growing nail.

CONCLUSION

The presentation of pycnodysostosis as tibial fracture is rare and there is limited literature on its management. We showed its approach focusing mainly on the management of the absent medullary canal.

Sclerotic bone lesions caused by non-infectious and non-neoplastic diseases: a review of the imaging and clinicopathologic findings

Bone sclerosis is a focal, multifocal, or diffuse increase in the density of the bone matrix on radiographs or computed tomography (CT) imaging. This radiological finding can be caused by a broad spectrum of diseases, such as congenital and developmental disorders, depositional disorders, and metabolic diseases. The differential diagnosis can be effectively narrowed by an astute radiologist in the light of the clinical picture and typical findings on imaging. Some of these lesions are rare and have been described as case reports and series in the literature. This article aims to collate the clinical-radiologic findings of non-infectious and non-neoplastic causes of bone sclerosis with relevant imaging illustrations.

Pycnodysostosis with Osteomyelitis of Maxilla: Case Report of Radiological Analysis

Pycnodysostosis is an autosomal recessive, rare genetic osteosclerotic disorder that caused by mutation in gene coding for Cathepsin K. The bones in pycnodysostosis are abnormally dense and brittle because of insufficient reabsorption process. This syndrome has a number of characteristic clinical and radiographic signs that differentiate it from other osteosclerotic conditions. This is a rare case report of a male patient with a history of multiple fractures of bones and osteomyelitis of maxilla which is a rare entity.

The Implications of Endocrinology in Orthodontics – Literature Review

Endocrinopathies have a variety of orofacial presentations which span from dental malocclusion to facial disfigurement. These characteristics depend on the nature and severity of the condition. An orthodontist should understand the body’s physiological processes to be able to timely determine the optimum intervention and plan treatment stages accordingly in compromised individuals. Communication between the two specialties should be well coordinated and should help facilitate quality health care to the patient. This review was aimed to impart the basic knowledge and the pivotal guidelines for orthodontic management in these conditions. Systemic conditions require multidisciplinary management and the dental team should aim to provide quality oral health care to enhance the overall quality of life and the orthodontist plays a vital role in helping patients achieve physical and psychological health.

Pycnodysostosis: Natural history and management guidelines from 27 French cases and a literature review

Pycnodysostosis is a lysosomal autosomal recessive skeletal dysplasia characterized by osteosclerosis, short stature, acro-osteolysis, facial features and an increased risk of fractures. The clinical heterogeneity of the disease and its rarity make it difficult to provide patients an accurate prognosis, as well as appropriate care and follow-up. French physicians from the OSCAR network have been asked to fill out questionnaires collecting molecular and clinical data for 27 patients issued from 17 unrelated families. All patients showed short stature (mean = -3.5 SD) which was more severe in females (P = .006). The mean fracture rate was moderate (0.21 per year), with four fractures in total average. About 75% underwent at least one surgery, with an average number of 2.1 interventions per patient. About 50% required non-invasive assisted ventilation due to sleep apnea (67%). About 29% showed psychomotor difficulties and 33% needed a school assistant or adapted schooling. No patient had any psychological evaluation or follow-up. Molecular data were available for 14 families. Growth hormone administration was efficient on linear growth in 40% of cases. We propose several axis of management, such as systematic cerebral MRI for Chiari malformation screening at diagnosis and regular psychological follow-up.

Clinical and radiographic features of pycnodysostosis: A case report

Pycnodysostosis is a rare disorder that was first described in 1962; however, it was only in 1996 that the defective gene was discovered, which led to a better understanding of this disease. This study reports and discuss a case of pycnodysostosis. In addition, a search of articles published in PubMed-Medline was performed. The case was a 13-year-old girl who was referred to a private clinic for dental treatment. Clinical examination showed midface hypoplasia, prominent cheeks, a high nasal bridge, beaked nose, spoon-shaped fingers, frontal bossing, open fontanelles and dental alterations, findings compatible with pycnodysostosis. Patients with this disease also suffer from fractures because of bone hardness with almost no elasticity, a fact that requires special care particularly in the case of children and adolescents. The diagnosis of pycnodysostosis is made based on clinical and radiographic findings. Clinicians should be aware of this disorder to provide adequate dental treatment.

Key words:Pycnodysostosis, developmental bone disease, imaging diagnosis.