Ramal inclination in the frontal plane after bimaxillary orthognathic surgery in skeletal class III facial asymmetry : Spontaneous changes and stability.

PURPOSE: This study aimed to observe spontaneous changes of ramal inclination in the frontal plane (FRI) and its stability in skeletal class III asymmetry patients corrected with bimaxillary surgery. The correlation between FRI change and surgical skeletal change was also investigated. METHODS: Forty-nine patients with skeletal class III facial asymmetry who underwent orthognathic surgery with at least 1° change in FRI after surgery were analyzed. FRI and other factors were measured on frontal and lateral cephalograms before surgery (T1), after surgery (T2), and at follow-up after at least 6 months (T3). Correlation analysis was performed to determine pre- and postoperative factors associated with FRI change and stability. RESULTS: FRI increased significantly on the deviated side and decreased on the nondeviated side after surgery. The FRI changes remained stable during follow-up. No correlation between FRI changes and skeletal changes during surgery were found except between the change of FRI during follow-up (T3-T2) and mandibular setback amount (T2-T1), with a weak coefficient of 0.32. CONCLUSION: The FRI changes after bimaxillary orthognathic surgery in skeletal class III asymmetry reduced the FRI difference between the deviated and nondeviated side and remained stable for at least 6 months after surgery. No clinically significant correlation was found between measured skeletal changes during surgery and FRI changes.

Effect of locally delivered protein complex-loaded nanoparticles on bone remodelling of atrophic alveolar ridge in beagles.

OBJECTIVE: To investigate the effect of local injection of mineralized hybrid nanoparticles loading dentin matrix protein-1 (DMP-1) and matrix metalloproteinase-13 (MMP-13) complex (P-NPs) on the bone remodelling on atrophic alveolar ridges (AAR) ahead of orthodontic tooth movement (OTM). SETTINGS AND SAMPLE POPULATION: Four beagles were randomly allocated into Group C (OTM only) and Group NP (OTM with P-NPs injection). Experimental model of AAR was prepared in 8 mandibular quadrants after extraction of the third premolars (n = 4 per Group). MATERIALS AND METHODS: Reciprocal traction of the second and fourth premolars was performed towards AAR for 8 weeks. P-NPs were prepared by loading recombinant DMP-1 and MMP-13 complex into calcium carbonate (CaCO3 )-mineralized hybrid nanoparticles and injected at 0, 3 and 6 weeks. The rate of OTM and the bone remodelling characteristics were compared between Groups using fluorescent microscopic analysis and microstructural histomorphometric analysis. RESULTS: Group NP revealed higher bone volume fraction and higher trabecular ratio with lower bone mineral density than Group C on AAR area. Meanwhile, the root movement towards AAR was facilitated in Group NP representing more bodily movement than Group C. CONCLUSION: Non-invasive intervention of P-NPs injection suggested a clinical potential to facilitate translational movement into the AAR with sustaining woven bone-like microstructural environment.

Automated Real-Time Evaluation of Condylar Movement in Relation to Three-Dimensional Craniofacial and Temporomandibular Morphometry in Patients with Facial Asymmetry.

The aim of this study was to investigate the correlation between craniofacial morphology, temporomandibular joint (TMJ) characteristics, and condylar functional movement in patients with facial asymmetry using an up-to-date automated real-time jaw-tracking system. A total of 30 patients with mandibular asymmetry and prognathism were included. Three-dimensional (3D) craniofacial and TMJ morphometric variables were analyzed in images captured using cone-beam computed tomography. Three-dimensional condylar movements were recorded during the opening, protrusion, and laterotrusion of the jaw and divided into those for deviated and non-deviated sides. Overall functional and morphometric variables were compared between the sides by a paired t-test. Pearson's correlation analysis and factor analysis were also performed. As a result, significant differences were found between the sides in morphometric and functional variables. The condylar path length was significantly longer and steeper on the deviated side during protrusion and lateral excursion. TMJ morphometric asymmetry, more so than the craniofacial morphologic asymmetry, seemed to be reflected in the functional asymmetry, representing different correlations between the sides, as supported by factor analysis. This study provides evidence explaining why the asymmetric condylar path remained unchanged even after orthognathic surgery for the correction of craniofacial asymmetry.

Effectiveness of 2D radiographs in detecting CBCT-based incidental findings in orthodontic patients.

Some craniofacial diseases or anatomical variations are found in radiographic images taken for other purposes. These incidental findings (IFs) can be detected in orthodontic patients, as various radiographs are required for orthodontic diagnosis. The radiographic data of 1020-orthodontic patients were interpreted to evaluate the rates of IFs in three-dimensional (3D) cone-beam-computed tomography (CBCT) with a large field of view (FOV) and investigate the effectiveness and accuracy of two-dimensional (2D) radiographs for detecting IFs compared to CBCT. Prevalence and accuracy in five areas was measured for sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). The accuracies of various 2D-radiograph were compared through a proportion test. A total of 709-cases (69.5%) of 1020-subjects showed one or more IFs in CBCT images. Nasal cavity was the most affected area. Based on the CBCT images as a gold standard, different accuracies of various 2D-radiographs were observed in each area of the findings. The highest accuracy was confirmed in soft tissue calcifications with comprehensive radiographs. For detecting nasal septum deviations, postero-anterior cephalograms were the most accurate 2D radiograph. In cases the IFs were not determined because of its ambiguity in 2D radiographs, considering them as an absence of findings increased the accuracy.

Palatal temporary skeletal anchorage devices (TSADs): What to know and how to do?

OBJECTIVES: Since palatal temporary skeletal anchorage devices (TSADs) have become important tools for orthodontic treatment, this narrative review was aimed to provide an updated and integrated guidelines for the clinical application of palatal TSADs. SETTING AND SAMPLE POPULATION: A narrative review article including researches on palatal TSADs in orthodontics related to anatomy, success rate and clinical application. MATERIALS AND METHODS: The anatomical characteristics, success rate and its consideration factors and clinical application of palatal TSADs based on the direction of tooth movement were evaluated. RESULTS: To improve the stability of TSADs, hard tissue factors such as bone depth, cortical bone thickness, bone density and soft tissue thickness were evaluated. Anatomically risky structures, including the nasopalatine foramen, canal and the greater palatine foramen, nerve, vessel need to be identified before placement. The success rate of palatal TSADs was greater than that of the buccal inter-radicular space. Palatal TSADs have been used for various purposes because they can control tooth movement in all directions and, three-dimensionally; their applications include the retraction of anterior teeth, protraction of posterior teeth, distalization, intrusion, expansion and constriction. They can be applied directly or indirectly to the lingual arch or transpalatal arch. Design modifications using splinted 2 miniscrews have been suggested. CONCLUSION: Palatal TSADs allow clinicians to perform minimally invasive and easy placement with good stability by understanding the anatomical characteristics of the palatal region, and they show good control over 3-dimensional tooth movements in various clinical cases.

Miniscrew-assisted rapid palatal expansion: A review of recent reports.

The miniscrew-assisted rapid palatal expander (MARPE) has extended not only skeletal effects with fewer dental changes and but also the age limit of nonsurgical maxillary expansion treatment. Amid its gaining popularity in clinical orthodontics, our current understanding of treatment effectiveness, efficiency, and stability needs to be reassessed. In this review article, the authors have attempted to evaluate MARPE from various aspects with a focus on recent studies.

Camouflage treatment of posterior bite collapse in a patient with skeletal asymmetry by using posterior maxillary segmental osteotomy.

Orthodontic treatment of posterior bite collapse due to early loss of molars and the consequent drift of adjacent teeth is complicated. When the posterior bite collapse occurs in patients with facial asymmetry, both transverse and vertical compensation are necessary for camouflage orthodontic treatment. In such cases, posterior maxillary segmental osteotomy (PMSO) can be an effective alternative procedure that simplifies the orthodontic treatment and shows long-term stability through dental compensation within the alveolar bone housing. This case report aimed to describe the orthodontic treatment of maxillary occlusal plane canting caused by severely extruded maxillary teeth in a patient with skeletal facial asymmetry that was corrected with PMSO along with protraction of the lower second molar to replace the space of the extracted first molar. The treatment duration was 18 months, and stable results were obtained after 2 years of retention.

Surface analysis of metal clips of ceramic self-ligating brackets.

OBJECTIVE: The aim of this study was to analyze the surface composition, roughness, and relative friction of metal clips from various ceramic self-ligating brackets. METHODS: Six kinds of brackets were examined. The control group (mC) consisted of interactive metal self-ligating brackets while the experimental group (CC, EC, MA, QK, and WA) consisted of interactive ceramic self-ligating brackets. Atomic force microscopy-lateral force microscopy and scanning electron microscopy-energy-dispersive X-ray spectroscopy were used to analyze the surface of each bracket clip. RESULTS: All the clips in the experimental groups were coated with rhodium except for the QK clip. The results showed that the QK clip had the lowest average roughness on the outer surface, followed by the MA, EC, WA, and CC clips. However, the CC clip had the lowest average roughness on the inner surface, followed by the QK, WA, MA, and EC clips. The QK clip also had the lowest relative friction on the outer surface, followed by the MA, EC, CC, and WA clips. Likewise, the CC clip had the lowest relative friction on the inner surface, followed by the QK, WA, MA, and EC clips. CONCLUSIONS: The surface roughness and relative friction of the rhodium-coated clips were generally higher than those of the uncoated clips.

Efficacy of Peracetic Acid (EndoPA®) for Disinfection of Endoscopes.

Background/Aims: We aimed to investigate the efficacy of peracetic acid (EndoPA® Firson Co., Ltd., Cheonan, Korea) in disinfecting endoscopes. Methods: We prospectively investigated the gastroscopes (Part I) utilized in 100 gastroscopic examinations and colonoscopes (Part II) utilized in 30 colonoscopic examinations after disinfecting them with 0.2% peracetic acid (EndoPA® Firson Co., Ltd.). These instruments had been collected consecutively throughout the study period. We reprocessed and disinfected the endoscopes according to the guidelines for cleaning and disinfecting gastrointestinal endoscopes laid down by the Korean Society of Gastrointestinal Endoscopy in 2017. Three culture samples were obtained from each examination, based on different sampling methods. The primary outcome was a positive culture rate. Results: In Part I of our study, two of 300 samples were positive. The culture positive rate after disinfection was 0.7% (2/300). The culture positive rate was not significantly different based on the exposure time to EndoPA® or the age of the scopes (p=0.7 or 0.2, respectively). In Part II of our study, all samples (n=90) were negative. Conclusions: We conclude that 0.2% peracetic acid (EndoPA®) appears to be a good disinfectant for both gastroscopes and colonoscopes.

Predictors of favorable soft tissue profile outcomes following Class II Twin-block treatment.

OBJECTIVE: The aim of this study was to determine cephalometric factors that help predict favorable soft-tissue profile outcomes following treatment with the Class II Twin-block appliance. METHODS: Pre- and post-treatment lateral cephalograms of 45 patients treated with the Class II Twin-block appliance were retrospectively analyzed. Profile silhouettes were drawn from the cephalograms and evaluated by three orthodontists in order to determine the extent of improvement. Samples were divided into a favorable group (upper 30% of visual analogue scale [VAS] scores, n = 14) and an unfavorable group (lower 30% of VAS scores, n = 14). Skeletal and soft-tissue measurements were performed on the cephalograms and an intergroup comparison was conducted. RESULTS: An independent t-test revealed that the following pre-treatment values were lower in the favorable group compared to the unfavorable group: lower incisor to mandibular plane angle, lower incisor to pogonion distance, point A-nasion-point B angle, sella-nasion line (SN) to maxillary plane angle, SN to mandibular plane angle, gonial angle, and symphysis inclination. The favorable group had a larger incisor inclination to occlusal plane. Moreover, the favorable group showed larger post-treatment changes in gonial angle, B point projection, and pogonion projection than did the unfavorable group. CONCLUSIONS: Class II malocclusion patients with a low divergent skeletal pattern and reduced lower incisor protrusions are likely to show more improvement in soft-tissue profile outcomes following Class II Twin-block treatment.

Effect of flapless osteoperforation-assisted tooth movement on atrophic alveolar ridge: Histomorphometric and gene-enrichment analysis.

OBJECTIVE: To investigate the effect of flapless osteoperforation on the tissue response of the atrophic alveolar ridge affected by orthodontic tooth movement (OTM). MATERIALS AND METHODS: An atrophic alveolar ridge model was established in the mandibular quadrants of eight beagle dogs. As a split-mouth design, the quadrants were randomly divided into group C (OTM only) and group OP (OTM with flapless osteoperforation). The rate of OTM for 10 weeks was compared between groups, and micro-CT-based histomorphometric analysis and RNA-sequencing-based gene-enrichment analysis were performed targeting the atrophic ridge. RESULTS: Group OP displayed more rapid tooth movement with lower bone mineral density and higher trabecular fraction in the atrophic ridge than did group C, showing no intergroup difference of total ridge volume. As contributing biological functional pathways in group OP, the genes related to osteoclast differentiation and TNF signaling pathway were up-regulated and those associated with Wnt signaling pathway and AMPK signaling pathway were down-regulated. CONCLUSIONS: Flapless osteoperforation facilitated the rate of OTM toward the atrophic ridge, maintaining low bone density, whereas it did not increase the volume of the atrophic ridge.

Depth and combined infection is important predictor of lower extremity amputations in hospitalized diabetic foot ulcer patients.

BACKGROUND/AIMS: As the prevalence of diabetes mellitus and its complications increase rapidly, diabetic foot ulcers (DFUs), which are a major diabetic complication, are expected to increase. For prevention and effective treatment, it is important to understand the clinical course of DFUs. The aim of this study was to investigate the natural course and predictors of amputation in patients with DFUs who required hospitalization. METHODS: A total of 209 patients with type 2 diabetes, aged 30 to 85 years, who visited emergency department or needed hospitalization due to DFUs were consecutively enrolled from May 2012 to January 2016, by retrospective medical record review. The main outcome was lower extremity amputation (LEA). RESULTS: Among 192 patients who completed follow-up, 113 patients (58.9%) required LEAs. Compared to patients without amputation, baseline levels of white blood cell counts and C-reactive protein were higher in patients with amputation. In addition, bone and joint involvement was more frequently observed in patients with amputation. Multivariable regression analysis revealed that combined infection (odds ratio [OR], 11.39; 95% confidence interval [CI], 2.55 to 50.93; p = 0.001) and bone or joint involvement (OR, 3.74; 95% CI, 1.10 to 12.70; p = 0.035) were significantly associated with an increased risk of LEA. CONCLUSION: The depth of the wound and combined infection of DFU, rather than the extent of the wound, were significant prognostic factors of LEAs in patients with type 2 diabetes.

Interfacial Layer Control by Dry Cleaning Technology for Polycrystalline and Single Crystalline Silicon Growth.

Native oxide removal prior to poly-Si contact and epitaxial growth of Si is the most critical technology to ensure process and device performances of poly-Si plugs and selective epitaxial growth (SEG) layers for DRAM, flash memory, and logic device. Recently, dry cleaning process for interfacial oxide removal has attracted a world-wide attention due to its superior passivation properties to conventional wet cleaning processes. In this study, we investigated the surface states of Si substrate during and after dry cleaning process, and the role of atomic elements including fluorine and hydrogen on the properties of subsequent deposited silicon layer using SIMS, XPS, and TEM analysis. The controlling of residual fluorine on the Si surface after dry cleaning is a key factor for clean interface. The mechanism of native oxide re-growth caused by residual fluorine after dry cleaning is proposed based on analytical results.

Promotion of osteoblastic differentiation and osteogenic transcription factor expression on a microgroove titanium surface with immobilized fibronectin or bone sialoprotein II.

We demonstrate that a composite surface of microgroove titanium (Ti) with immobilized fibronectin (FN) or bone sialoprotein II (BSP2) promotes osteoblastic differentiation and osteogenic transcription factor expression in human bone marrow-derived mesenchymal stem cells (MSCs). Comparisons made between smooth microgrooves, microgrooves with silanization and microgrooves with matrix protein (FN or BSP2)-immobilization Ti surfaces revealed a significant promotion of in vitro osteogenic activity and osteoblastic differentiation at various timelines of culture. An even more significant increase was verified on microgrooves with a matrix protein-immobilization Ti surface in 28 d time-dependent gene expression of the main osteogenic transcription factors, such as ARF4, FRA1, RUNX2, and OSX. As a result, a synergestic effect regarding the promotion of osteogenic transcription factor expression and osteoblastic differentiation in the matrix protein-microgroove Ti composite surface was confirmed. From a multiple regression analysis using various timelines of osteogenic culture as independent variables, day 13 was verified as the most prominent influential timeline for the promotion of osteoblastic differentiation induced by the matrix protein-microgroove Ti composite surface. The FN- or BSP2-microgroove Ti composite surface resulting from silanization can strongly induce the promotion of osteoblastic differentiation in human MSCs. The proposed surface is expected to be useful in the development of a variety of osteogenic biomaterial surfaces.

A New Designed Expander Supported by Spike Miniscrews With Enhanced Stability.

INTRODUCTION: This article represents a new design of expander-spike expander-to correct transverse maxillary deficiency. This new type appliance is easy to fabricate, more hygienic, and less soft-tissue irritation because of elimination of acrylic plate. In addition, because of the position of mini-implant, it can provide a relatively parallel alveolar expansion, compared with other types of expander. MATERIALS AND METHODS: The spike expander consists of 2 parts: 4 spike screws and an expansion screw. Four spike screws were placed on the palatal slope. After installation of the spike screws, based on the position of spike screw, the extension arms of expansion screw were bended on the cast model, and connected to the spike screws by adding resin. The expansion screw was turned once a day (0.25 mm/d), and the process was terminated at 6 weeks. RESULTS: The stability and design of the spike screw enable widening of maxilla easier. Compared with other expander, spike expander reduces the forces being placed directly on teeth, which can maximize skeletal expansion, minimize dental tipping, produce a relatively parallel expansion, and reduce soft-tissue irritation caused by acrylic pads. Furthermore, the teeth can be aligned and leveled simultaneously using the fixed appliance because teeth are free of contact by the expander. And the best point for spike expander is that it is simply fabricated and removed. CONCLUSIONS: The design of spike expander is combining spike screws and an expansion screw, which can provide a good and easy treatment method for transverse maxillary deficiency.

Analysis of midpalatal miniscrew-assisted maxillary molar distalization patterns with simultaneous use of fixed appliances: A preliminary study.

Skeletal anchorage-assisted upper molar distalization has become one of the standard treatment modalities for the correction of Class II malocclusion. The purpose of this study was to analyze maxillary molar movement patterns according to appliance design, with the simultaneous use of buccal fixed orthodontic appliances. The authors devised two distinct types of midpalatal miniscrew-assisted maxillary molar distalizers, a lingual arch type and a pendulum type. Fourteen patients treated with one of the two types of distalizers were enrolled in the study, and the patterns of tooth movement associated with each type were compared. Pre- and post-treatment lateral cephalograms were analyzed. The lingual arch type was associated with relatively bodily upper molar distalization, while the pendulum type was associated with distal tipping with intrusion of the upper molar. Clinicians should be aware of the expected tooth movement associated with each appliance design. Further well designed studies with larger sample sizes are required.

Combined effect of photobiomodulation with a matrix metalloproteinase inhibitor on the rate of relapse in rats.

OBJECTIVE: To investigate combined effect of photobiomodulation with a matrix metalloproteinase (MMP) inhibitor on the relapse rate in relation to MMP expression in rats. MATERIALS AND METHODS: Fifty-two rats were divided into four groups according to the treatment modality: control group, irradiation group, doxycycline group, and irradiation with doxycycline group. During a relapse period of 5 days after orthodontic movement, maxillary central incisors were treated by low-level laser therapy (LLLT) as a photobiomodulation and/or doxycycline as a synthetic MMP inhibitor. Relapse rate was evaluated in association with MMP expression at the gene and protein levels. RESULTS: Relapse rates were increased by LLLT (1.57-fold) and decreased by doxycycline (0.83-fold) compared with the control, showing positive correlation with the levels of expression for all MMPs in the periodontal ligament (PDL). LLLT concomitant with doxycycline administration resulted in no significant differences of relapse rate and MMP expression from the control. CONCLUSIONS: The combined effect of photobiomodulation with an MMP inhibitor around the relapsing teeth proved to be antagonistic to PDL remodeling activity during relapse. This study suggests a basis for developing a novel biologic procedure targeting the MMP-dependent PDL remodeling to control the relapse rate.

Uprighting mesially impacted mandibular molars with 2 miniscrews.

Mesially tilted or impacted mandibular molars cause occlusal disharmony and periodontal problems. For proper restoration of the occlusion and to prevent further periodontal damage, uprighting of tilted molars is the recommended treatment option. Although several orthodontic methods including miniscrews have been proposed, most of them have innate limitations and problems such as the possibility of unwanted tooth movement. In this case series, we introduce a new system that uses 2 miniscrews with slots that can accommodate rectangular orthodontic wires to 3 dimensionally control the tilted molar in 3 patients. We also discuss the advantages and possible disadvantages of this new system.

Induction of S100A4 in periodontal ligament cells enhances osteoclast formation.

BACKGROUND: An increase in the expression of S100A4 has been reported in various inflammatory diseases. However, little is known about the association between periodontal inflammation and S100A4 expression. The aims of this study were to investigate changes in S100A4 expression in human periodontal ligament (hPDL) cells in response to inflammatory stimuli and to describe a possible mechanism underlying the change. METHOD: Human PDL cells were treated with lipopolysaccharide (LPS) and the level of S100A4 was analyzed by real-time RT-PCR and Western blotting. LPS was added to co-cultures of hPDL and osteoclast progenitor cells under osteoclastogenic condition and the formation of osteoclasts was assessed. Alternatively, progenitor cells were directly treated with recombinant S100A4 for evaluation of osteoclastogenesis. The activity of nuclear factor kappaB (NFκB) was examined by Western blotting for phosphorylated forms of inhibitor kappaB (IκB) and p65. An NFκB inhibitor was added to the culture of hPDL cells with LPS and the level of S100A4 was measured by real-time RT-PCR. RESULTS: We found that LPS stimulation resulted in a significant increase of S100A4 expression in hPDL cells. S100A4 protein secretion from hPDL cells was also increased. The enhanced expression of S100A4 in hPDL cells under inflammatory conditions led to stimulation of the generation of osteoclasts. In addition, direct S100A4 treatment stimulated osteoclastogenesis. The underlying mechanism for the increased S100A4 expression in hPDL cells was activation of the NFκB signaling pathway. CONCLUSION: Our results suggest that bone destruction in periodontitis might be associated with increased S100A4 expression in hPDL cells.

Effects of increased low-level diode laser irradiation time on extraction socket healing in rats.

In our previous studies, we confirmed that low-level laser therapy (LLLT) with a 980-nm gallium-aluminum-arsenide diode laser was beneficial for the healing of the alveolar bone in rats with systemic disease. However, many factors can affect the biostimulatory effects of LLLT. Thus, we attempted to investigate the effects of irradiation time on the healing of extraction sockets by evaluating the expressions of genes and proteins related to bone healing. The left and right first maxillary molars of 24 rats were extracted. Rats were randomly divided into four groups in which extraction sockets were irradiated for 0, 1, 2, or 5 min each day for 3 or 7 days. Specimens containing the sockets were examined using quantitative real-time reverse transcription polymerase chain reaction and western blotting. LLLT increased the expressions of all tested genes, Runx2, collagen type 1, osteocalcin, platelet-derived growth factor-B, and vascular endothelial growth factor, in a time-dependent manner. The highest levels of gene expressions were in the 5-min group after 7 days. Five minutes of irradiation caused prominent increases of the expression of all tested proteins after both 3 and 7 days. The expression level of each protein in group 4 was higher by almost twofold compared with group 1 after 7 days. Laser irradiation for 5 min caused the highest expressions of genes and proteins related to bone healing. In conclusion, LLLT had positive effects on the early stages of bone healing of extraction sockets in rats, which were irradiation time-dependent.