Craniofacial Morphology and Upper Airway Dimensions in Patients with Hypermobile Ehlers-Danlos Syndrome Compared to Healthy Controls

Head Posture and Upper Spine Morphological Deviations in Patients With Hypermobile Ehlers-Danlos Syndrome

OBJECTIVE

To compare head posture and upper spine morphology in hypermobile Ehlers-Danlos syndrome (hEDS) patients with healthy controls with neutral occlusion.

MATERIALS AND METHODS

The study consisted of 27 hEDS patients (23 females, 4 males, mean age 36.41 ± 11.35) and 39 healthy controls (28 females, 11 males, mean age 31.85 ± 11.35) with neutral occlusion and no previous orthodontic treatment. Head posture was analysed by angular measurements on lateral cephalograms taken in natural head position and upper spine morphology was assessed on Cone Beam Computed Tomography (CBCT) by visual analysis of fusion and partial cleft of the upper spine and compared by general linear and logistic analyses adjusted for age and gender.

RESULTS

In total, upper spine morphological deviations occurred significantly more often in hEDS patients (51.9%) compared to controls (15.4%) (p = 0.007). Out of the two categories of upper spine morphological deviations (fusion anomalies and posterior arch deficiencies (PAD)), PAD occurred significantly more often in hEDS patients (48.1%) compared to controls (12.8%) (p = 0.007). The differences remained significant when p-values were corrected for multiple testing comparing groups. Head posture was almost significantly more extended in hEDS patients compared to controls when the p-values were corrected for multiple testing comparing groups (NSL/VER, p = 0.089; NSL/OPT, p = 0.080).

CONCLUSIONS

The results of the present study indicate that upper spine morphology is affected in hEDS patients. The results may contribute to a further understanding of the spinal phenotypic spectrum in hEDS patients and thus prove valuable in the diagnostics and treatment of hEDS patients.

Oro-Dental Characteristics in Patients With Adult-Onset Hypophosphatasia Compared to a Healthy Control Group-A Case-Control Study

BACKGROUND

Hypophosphatasia (HPP) is a rare inherited disease that affects multiple organ systems including bone and teeth. Limited knowledge exists on dental and oral health in patients with adult-onset HPP (aHPP).

OBJECTIVE

The aim of this study was to investigate oro-dental characteristics in patients with aHPP compared to healthy controls.

METHODS

This case-control study included 20 patients with aHPP compared to 31 healthy controls. Oro-dental manifestations were examined by standardised interviews, clinical examinations as well as radiological registrations on panoramic radiograph (OP) and cone-beam computed tomography (CBCT) scans.

RESULTS

The subjective experience of tooth fractures (p = 0.010), caries in permanent teeth (p = 0.032) and early loss of permanent teeth (p = 0.002) was significantly higher in patients with aHPP compared to the controls. In the aHPP group, the presence of specific teeth (p ≤ 0.045) and attrition of 11 were significantly lower (p = 0.012) compared to the controls. Opacity of a few teeth (p ≤ 0.049), presence of denticles (p = 0.024), the distance between the enamel-cement junction (CEJ) and the marginal bone level at specific sites (p ≤ 0.021) and crown height of 11 (p = 0.017) were significantly higher in patients with aHPP than in healthy controls.

CONCLUSION

The results indicate that patients with aHPP have a subjective experience of having poorer dental health. Loss of permanent teeth, less attrition, tooth opacities, denticles and larger distance between CEJ and marginal bone level are possible oro-dental findings in patients with aHPP.

Craniofacial sutures: Signaling centres integrating mechanosensation, cell signaling, and cell differentiation

Cranial sutures are dynamic structures in which stem cell biology, bone formation, and mechanical forces interface, influencing the shape of the skull throughout development and beyond. Over the past decade, there has been significant progress in understanding mesenchymal stromal cell (MSC) differentiation in the context of suture development and genetic control of suture pathologies, such as craniosynostosis. More recently, the mechanosensory function of sutures and the influence of mechanical signals on craniofacial development have come to the forefront. There is currently a gap in understanding of how mechanical signals integrate with MSC differentiation and ossification to ensure appropriate bone development and mediate postnatal growth surrounding sutures. In this review, we discuss the role of mechanosensation in the context of cranial sutures, and how mechanical stimuli are converted to biochemical signals influencing bone growth, suture patency, and fusion through mediation of cell differentiation. We integrate key knowledge from other paradigms where mechanosensation forms a critical component, such as bone remodeling and orthodontic tooth movement. The current state of the field regarding genetic, cellular, and physiological mechanisms of mechanotransduction will be contextualized within suture biology.