[Effects of mid-palatal suture opening and midfacial bony structure changes induced by maxillary skeletal expansion in adults].

PURPOSE: To analyze the opening of mid-palatal suture, transverse changes in dental and dentoalveolar measurements and shift of midfacial bony structures induced by maxillary skeletal expansion (MSE) with cone-beam CT (CBCT), and to evaluate the effect of maxillary skeletal expansion and its influence on adjacent bony structures in adults. METHODS: The study sample consisted of 12 adult patients with maxillary transverse deficiency (4 males, 8 females) at a mean age of (21.17±4.13) years old. All patients were treated with MSE. After treatment, the posterior crossbite was corrected, and the width of the maxillary arch was achieved the optimal width. Pre- and post-treatment CBCT exams were taken before and after MSE treatment. Multiplanar coronal and axial slices obtained from CBCT images were used to measure the changes in transverse widths, angular changes and tooth inclination with Dolphin Imaging 11.9. SPSS 26.0 software package was used for statistical analysis. RESULTS: After MSE treatment, the anterior nasal spine width increased by (2.38±1.01) mm, posterior nasal spine width increased by (2.25±1.08) mm (P<0.01). The inter-crown and inter-apex distance at the first molar increased by (5.56±1.38) mm and (4.14±1.29) mm, respectively (P<0.01). No significant difference was seen in terms of tooth inclination of the first molar(P>0.05). Pterygoid process angle, pterygoid process width, anterior inter-maxillary distance, upper and lower inter-zygomatic distance were significantly larger after treatment (P<0.01), while the inter-temporal distance and bilateral zygomaticomaxillary angle remained unchanged(P>0.05). CONCLUSIONS: MSE has a favorable effect in adult patients with parallel skeletal expansion of the mid-palatal suture achieved after expansion. The teeth present with certain buccal inclination but show no significant movement relative to the alveolar bone. The midfacial bony structures also shift in three-dimensional under the effect of the expansion force.

Napabucasin Induces Mouse Bone Loss by Impairing Bone Formation via STAT3.

The novel small molecule Napabucasin (also known as BBI608) was shown to inhibit gene transcription driven by Signal Transducer and Activator of Transcription 3 (STAT3), which is considered a promising anticancer target. Many preclinical studies have been conducted in cancer patients examining the selective targeting of cancer stem cells by Napabucasin, but few studies have examined side effects of Napabucasin in the skeleton system. In the present study, we found treating bone marrow mesenchymal stem cells (BMSCs) with Napabucasin in vitro impaired their osteogenic differentiation. In terms of mechanisms, Napabucasin disrupted differentiation of BMSCs by inhibiting the transcription of osteogenic gene osteocalcin (Ocn) through STAT3. Moreover, through micro-CT analysis we found 4 weeks of Napabucasin injections induced mouse bone loss. Histological analysis revealed that Napabucasin-induced bone loss in mice was the result of impaired osteogenesis. In conclusion, this study provided evidence for the effect of Napabucasin on mouse bone homeostasis and revealed its underlying mechanisms in vivo and in vitro.

Evaluation of post-surgical stability in skeletal class II patients with idiopathic condylar resorption treated with functional splint therapy.

PURPOSE: To assess postsurgical stability of mandibular advancement combined with orthodontic treatment, following functional splint therapy, in patients with idiopathic condylar resorption (ICR). PATIENTS AND METHODS: Sixteen patients who were treated with functional splint therapy followed by orthognathic surgery combined with orthodontic treatment between 2010 and 2017 were included in this retrospective study. The primary outcome variable was skeletal stability, measured on the y-axis to point B (y-axis-B). Cephalometric analysis, including measurement of temporomandibular joint spaces, was carried out on serial magnetic resonance images (MRI) prior to orthognathic surgery (T0), immediately after surgery (T1), and after at least 1 year of follow-up (T2). The differences in the data between time points were compared using statistical analyses. RESULTS: All patients obtained an esthetic facial profile after orthognathic surgery, with normal occlusion as well as normal protrusive and laterotrusive excursion after treatment. Mean advancement of the mandible immediately following surgery (y-axis-B, T1 - T0) was 7.28 ± 5.79 mm. This was the only skeletal measurement that showed a sagittal positional change of the mandible. Mean backward movement (T2 - T1) was -1.04 ± 2.35 mm (p2 = 0.116). Thirteen out of 16 patients experienced no postsurgical relapse or less than 2 mm of mandibular backward movement (81.25%), while two out of 16 patients showed more than 2 mm of mandibular backward movement (12.5%). CONCLUSIONS: Patients who underwent mandibular advancement combined with orthodontic treatment, following functional splint therapy, exhibited a stable mandibular position at the 1-year follow-up. This study indicated that functional splint therapy prior to orthognathic surgery for mandibular advancement may be a good adjuvant treatment for ICR patients.