Surgical Orthodontic Treatment for Skeletal Class I with Facial Asymmetry and Occlusal Cant: A Case Report

Background: Cases of facial asymmetry with chin deviation and canted occlusal plane represent a challenge in orthodontic treatment. Case Report: We report successful surgical orthodontic treatment for skeletal Class I with severe facial asymmetry. Miniscrew anchorage was used to decompensate the canted occlusal plane in presurgical orthodontic treatment with a fixed appliance by the intrusion of the maxillary right molars and extrusion of the left molars. Then, orthognathic surgery consisting of bilateral sagittal split osteotomy for asymmetric mandibular setback was performed. Treatment resulted in marked improvement of facial asymmetry. Conclusion: The use of miniscrew implant anchorage may represent a superior presurgical orthodontic treatment and expand the possibility of treatment by one-jaw surgery.

MicroRNA expression profiles in peri-miniscrew implant crevicular fluid in orthodontics: a pilot study

Background This study systematically evaluated microRNA (miRNA) expression patterns in peri-miniscrew implant crevicular fluid (PMICF) in orthodontic patients. Methods Next-generation sequencing (NGS) was performed to obtain miRNA profiles in PMICF or gingival crevicular fluid (GCF) collected from 3 healthy volunteers (H), 3 peri-implantitis patients (PMSII) and 5 periodontitis patients (P). MiRNA expression patterns were compared between normal and orthodontic PMICF and GCF. Differentially expressed miRNAs were estimated by quantitative real-time PCR (qRT-PCR). Enrichment analyses of the gene targets controlled by these miRNAs were conducted by Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Results Compared with healthy donors, in PMSII patients, a total of 206 upregulated miRNAs and 152 downregulated miRNAs were detected in PMICF, while periodontitis patients had 333 upregulated miRNAs and 318 downregulated miRNAs. MiR-544a, miR-1245b-3p, miR-1825, miR-4291, miR-3689e, and miR-4477a were chosen randomly for further examination. qRT-PCR examination confirmed that the expression levels of miR-1245b-3p and miR-4291 were higher in PMSII than in H samples and that the expression levels of miR-1825 were higher in PMSII than in P samples. However, contrary to the NGS results, qRT-PCR analysis showed decreased expression of miR544a in PMSII. MiR3689e and miR4477a expression did not differ significantly among all samples. According to GO and KEGG pathway analyses of miR-1825, miR-4291, and miR-1245b-3p high enrichment of target genes involved in the PI3K-AKT signalling pathway was observed. Conclusions The NGS analysis of normal and orthodontic PMICF/CGF showed different miRNA profiles, which may lay the foundation for future research on the molecular mechanism of PMSII. miR-4291, miR-1245b-3p and miR-1825 may be used as diagnostic markers and potential therapeutic targets for PMSII.

Expression of circulating cell-free nucleic acids around miniscrew implant during orthodontic tooth movement—a prospective study

Objectives Literature shows that the expression of various biomarkers in peri-miniscrew crevicular fluid (PMICF) is related to the stability of miniscrew implants (MSIs). The present study investigated the role and alterations in levels of circulating cell-free nucleic acids (cfNAs) in PMICF before and after orthodontic loading. Material and methods This prospective study consisted of forty-six MSIs placed between the second premolar and first molar in the maxillary and mandibular arches. Direct loading was done after 3 weeks of MSI insertion with nickel-titanium closed coil spring exerting a force of 200 g. The PMICF sample was collected at various time intervals, and the level of cfNA was determined. Clinical parameters, including implant mobility and gingival health, were also assessed. Pre-loading and post-loading parameters were assessed using Wilcoxon’s rank-sum test. Results Among 46 MSIs, 36 were stable during the study and 10 MSIs showed peri-implant inflammation and increased mobility. There was a significant rise in the cfNA concentration 24 h after implant insertion (0.4 ± 0.86 ng/μl). The level of cfNAs significantly decreased over 3 weeks and reached the baseline level (0.2 ± 0.31 ng/μl). There was also a significant rise in the levels of cfNA (0.8 ± 0.70 ng/μl) at 24 h after loading MSIs, which gradually decreased to 0.2 ± 0.24 ng/μl after 63 days. The expression of cfNAs was on the average 0.32 units more in the cases with failed implants (P = 0.05). Conclusions cfNA levels in PMICF showed an upward trend 24 h after MSI insertion and 24 h after orthodontic loading. The expression of cfNA was more in cases with failed MSIs. Hence, the cfNAs can be considered as a prognostic biomarker of MSI stability.

Measurement of inter radicular bone width in different growth patterns for determining safe zone for placement of miniscrew implants – A cone beam computed tomography study

To measure the inter-radicular spaces in both arches for miniscrew implant placement and to determine the most reliable sites using CBCT. A CBCT radiograph was taken for 75 subjects that met with inclusion criteria. They were divided into 3 categories- Hypodivergent, average, and hyperdivergent group. Images were calibrated by using software and printed as a film. Interradicular space on the right side of the jaw was measured in the sagittal plane after assuming the jaw to be symmetrical. Bucco-lingual and mesiodistal width were measured up to desired bone levels. In vertical growth pattern, in posterior maxilla highest mesiodistal width between 2nd premolar and 1st molar at 7mm. In the mandible, it was between the 1st and 2nd molar at 11mm. In horizontal growth pattern, in posterior maxilla highest mesiodistal width between 1st and 2nd premolar, and mandible it was between 1st and 2nd molar at 11mm. In average growth pattern, in posterior maxilla highest mesiodistal width between 2nd premolar and 1st molar and 1st molar at 7mm. In the mandible, it was between the 1st and 2nd molar at 11mm. The importance of the relationship between the growth pattern and the availability of inter radicular space may aid the clinician in planning appropriate surgical sites for miniscrew implant placement.

Torque Requirements and the Influence of Pilot Holes on Orthodontic Miniscrew Microdamage

This study aimed to quantify the microdamage to cortical bone of different thickness and the maximum insertion torque during orthodontic miniscrew implant (OMI) placement with and without a pilot hole. Forty-five porcine bone specimens were prepared with thicknesses of 1.5, 2 and 2.5 mm. Ten bone specimens per thickness had a pilot hole drilled prior to the insertion of an OMI, and the remaining 15 bone specimens had an OMI without a pilot hole inserted. Sequential staining was used to identify damage caused by bone preparation and surface microdamage from OMI insertion and confocal laser microscopy images were used to quantify damage characteristics. Of the five damage characteristics, only one decreased when a pilot hole was used for all bone specimens (p = 0.025), while two increased as cortical bone thickness increased (p = 0.0064, p = 0.0003). There was no evidence that maximum insertion torque differed according to pilot hole status (p = 0.1144) and increased as cortical bone thickness increased (p = 0.0001). The presence of a pilot hole had minimal effect on microdamage characteristics and no effect on maximum insertion torque. As cortical bone thickness increased, an increase in microdamage and in maximum insertion torque was observed.