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Objectives To determine the accuracy of three-dimensional (3D) printed models fabricated from cone-beam computed tomography (CBCT) scans of human mandibular dry skulls in comparison with models derived from intraoral scanner (IOS) data. Materials and Methods Six human mandibular dry skulls were scanned by IOS and CBCT. Digital models (DMs) constructed from the IOS and CBCT data were fabricated physically using a 3D printer. The width and thickness of individual teeth and intercanine and molar widths were measured using a digital caliper. The accuracy of the DMs was compared between IOS and CBCT. Paired t-tests were used for intergroup comparisons. Results All intraclass correlation coefficient values for the three measurements (mesial-distal, buccal-lingual, width) exceeded 0.9. For the mandibular teeth, there were significant discrepancies in model accuracy between the IOS (average discrepancies of 0.18 ± 0.08 mm and 0.16 ± 0.12 mm for width and thickness, respectively) and CBCT (0.28 ± 0.07 mm for width, 0.37 ± 0.2 mm for thickness; P < .01). Intercanine (P = .38) and molar widths (P = .41) showed no significant difference between groups. Conclusions There was a statistically significant difference in the accuracy of DMs obtained from CBCT and IOS; however, this did not seem to result in any important clinical difference. CBCT could be routinely used as an orthodontic diagnostic tool and for appliance construction.

Infectious bronchitis virus (IBV) is the causative agent of infectious bronchitis (IB) in chickens. There is a correlation between cross-protection and percentage of similarity between nucleotide sequences encoding the S1 subunit, which is responsible for generating neutralizing and serotype-specific antibodies. Therefore, RT-PCR is commonly used to amplify the IBV-S1 gene following DNA sequencing in order to predict the efficacy of vaccines against IBV strains. We successfully enhanced the sensitivity for detection of the IBV-S1 gene by second PCR after purification of the 1st RT-PCR product. Using that method, we obtained detailed information on the prevalence of IBV on poultry farms in Gifu Prefecture, Japan. The IBV-S1 gene detection method used in the current study will enable accurate information on the prevalence of IBV in Japan to be obtained.

Minimally invasive esophagectomy (MIE) is increasingly performed to expect lower complication rate compared to open esophagectomy. Studies of minimally invasive Ivor Lewis esophagectomy (MIILE) with circular staplers have reported better outcomes compared to MIE with cervical anastomosis, but frequent anastomotic complications have also been reported. MIILE with linear staplers is a promising alternative, but the long-term functional and oncological outcomes are uncertain. To evaluate the functional and oncological outcomes of MIILE with linear stapled anastomosis, a retrospective cohort study was performed in 104 patients who underwent MIILE with linear stapled anastomosis for esophageal malignant tumors. The primary endpoints were the overall complication and anastomotic leak rates. The secondary endpoints were late complications, overall and disease-free survival, and nutritional status at 6 and 12 months after MIILE. Anastomotic leak occurred in 4 patients (3.8%). The short-term complication rate of grade IIIb or higher was 6.7%. During a median 57-month follow-up period, anastomotic stricture occurred in one patient, 7 required hiatal hernia repair, and 2 underwent conduit revision surgery. The 5-year overall survival and disease-free survival rates were 69.3% and 59.5%, respectively. Status of reflux esophagitis at the time of most recent evaluation was grade N/A/B/C/D in 52/10/10/13/8 among 93 patients who had follow-up endoscopy. The mean body weight loss at 6 and 12 months after MIILE was 11.3 and 11.8% with maintenance of the serum albumin level. MIILE with linear stapled anastomosis is a safe procedure with a low anastomotic complication rate and favorable long-term functional and survival outcomes.

Aim To present a case of skeletal mandibular protrusion with multiple impacted ankylosed teeth, which were treated with conventional orthognathic surgery and alveolar corticotomy, respectively. Background Tooth ankylosis is characterized by the fusion of a root surface with the surrounding alveolar bone. Various treatment modalities for tooth ankylosis have been developed and are used commonly in the clinic. Corticotomy is defined as the application of intentional surgical injury to the cortical bone to mobilize a tooth with the adjacent bone and soft tissues. The corticotomy technique has been improved in recent years to avoid possible risks such as periodontal damage, tooth devitalization, and osseous necrosis due to an inadequate blood supply. Case description A female patient aged 16 years and 3 months was diagnosed with anterior crossbite and the impaction and ankylosis of multiple canines. After the confirmation of ankylosis, alveolar corticotomy was performed on the maxillary left and mandibular right canines. After 6 months of traction (patient age, 19 years and 7 months), both canines had extruded successfully. After the completion of preoperative treatment, bilateral intraoral vertical ramus osteotomy was performed to correct the anterior crossbite involving a skeletal mandibular protrusion. The amounts of mandibular setback on the right and left sides were approximately 7 and 5 mm, respectively. The total treatment period was 55 months. Acceptable occlusion with a balanced profile was maintained over a 5-year retention period, indicating the long-term stability and success of the treatment. Conclusion Our results indicate that alveolar corticotomy should be considered to facilitate the treatment of multiple impacted ankylosed teeth. Clinical significance This report proposes an efficacy of alveolar corticotomy for extrusion of impacted ankylosed teeth.

Objectives To investigate the role of hypoxia-inducible factor 1 alpha (HIF-1 alpha) signaling, the expression profile of M1 and M2 macrophages, and the role of the sphingosine 1-phosphate (S1P)/S1P receptor system in palatal wound healing of heterozygous HIF-1 alpha-deficient (HIF-1 alpha HET) mice. Materials and methods HIF-1 alpha HET and wild-type (WT) littermates underwent palatal tissue excision at the mid-hard palate. Histological analysis, immunostaining, real-time PCR, Western blotting (WB), and cellular migration assays were performed to analyze wound closure and macrophage infiltration. Results DMOG pretreatment showed an acceleration of palatal wound closure in WT mice. In contrast, the delayed palatal wound closure was observed in HIF-1 alpha HET mice with diminished production of Col1a1, MCP-1, and MIP-1 alpha, compared with WT mice. Decreased infiltration of M1 macrophage (F4/80(+)TNF-alpha(+), F4/80(+)iNOS(+)) and M2 macrophage (F4/80(+)Arginase-1(+), F4/80(+)CD163(+)) was observed. The numbers of F4/80(+)S1P(1)(+) macrophages of HIF-1 alpha HET wounded tissues were significantly lower compared with WT tissues. S1P treatment of bone marrow macrophages (BMMs) significantly upregulated expression of S1P(1) in WT mice compared with HIF-1 alpha HET. Phosphorylation of MAPK rapidly decreased in BMMs of HIF-1 alpha HET mice than in BMMs of WT mice by S1P stimulation. Moreover, S1P enhanced HIF-1 alpha expression via S1P(1) receptors to affect macrophage migration. Conclusions HIF-1 alpha deficiency aggravates M1 and M2 macrophage infiltration and controls macrophage motility via S1P/S1P(1) signaling. These results suggest that HIF-1 alpha signaling may contribute to the regulation of palatal wound healing.

Objective: We aimed to identify the immunoregulatory role of the cyclin-dependent kinase inhibitor p21 in the homeostasis of mandibular condylar cartilage affected by mechanical stress. Materials and Methods: Ten C57BL/6 wild-type (WT) and ten p21–/– mice aged 8 weeks were divided into the untreated and treated groups. In the treated groups, mechanical stress was applied to the temporomandibular joint (TMJ) through forced mouth opening for 3 h/day for 7 days. The dissected TMJs were assessed using micro-CT, histology, and immunohistochemistry. Results: Treated p21–/– condyles with mechanical stress revealed more severe subchondral bone destruction, with thinner cartilage layers and smaller proteoglycan area relative to treated WT condyles; untreated WT and p21–/– condyles had smoother surfaces. Immunohistochemistry revealed significant increases in the numbers of Caspase-3, interleukin-1β, matrix metalloprotease (MMP)-9, and MMP-13 positive cells, and few aggrecan positive cells, in treated p21–/– than in treated WT samples. Moreover, the number of TUNEL positive cells markedly increased in p21–/– condyles affected by mechanical stress. Conclusion: Our findings indicate that p21 in chondrocytes contributes to regulate matrix synthesis via the control of aggrecan and MMP-13 expression under mechanical stress. Thus, p21 might regulate the pathogenesis of osteoarthritis in the TMJ.

The enhancement in the bonding strength of advanced dental cements has enabled long-lasting dental restorations. However, the high bonding strength can cause difficulty in removing these restorations. Therefore, “smart” dental cements with simultaneous strong bonding and easy on-demand debonding ability are required. A resin-modified glass-ionomer-cement (RMGIC) with an ionic liquid (IL) has demonstrated significant reduction in the bonding strength with current application (CA). This research investigates the effects of immersion in distilled water on the electric conductivity and bonding strength of RMGIC with and without an IL and CA. The RMGIC without the IL exhibited significant electric conductivity after immersion, and a significant decrease in bonding strength with CA. In comparison, the electric conductivity after immersion and the decrease in bonding strength with CA were greater for RMGIC with the IL. Thus, the feasibility of smart dental cements capable of electrically debonding-on-demand is indicated.

Background/purpose: Even after surgical orthodontic treatment, the level of masticatory function in patients with jaw deformities is still lower than that of healthy subjects. The purpose of this study was to evaluate the effects of functional training program using gum chewing exercise after orthognathic surgery on masticatory function in patients with mandibular prognathism. Materials and methods: The study subjects were 16 patients with mandibular prognathism who underwent orthognathic surgery and 8 individuals with normal occlusion. Patients were divided into two groups (training group and non-training group; n = 8 per group). Functional training included gum chewing exercise and patient-education about masticatory function. The training; gum chewing exercise of 5 min twice a day for 90 days, started at 3 months after surgery. For each subject, electromyographic activities of masseter and temporalis muscles during maximum voluntary clenching (MVC) and jaw movement during gum chewing were recorded before and after surgical orthodontic treatment. Two parameters; activity index (AI: ratio of activity of masseter and temporalis muscles) and error index (EI: ratio of the number of abnormal chewing patterns), were used. Results: In the training group, the AI value during MVC increased significantly and the EI value during gam chewing decreased significantly after surgical orthodontic treatment (AI: p

Advancements in dental cements have considerably improved their bond strengths. However, high bond strength often makes the removal of restorations difficult. Thus, smart dental cements that show controllable bond strength are required. A conventional resin-modified glass-ionomer-cement demonstrated a significant reduction in the bond strength after current application. However, for this system, the ions in the cement are released into the oral cavity, resulting in a reduction of the electrical conductivity and in losses of the expected on-demand debonding property. Herein, the effects of immersion in 0.9 and 15% NaCl solutions on the electrical conductivity and debonding properties were investigated. The cement immersed in 0.9% NaCl solution from 1 to 28 days maintained similar bond strength reductions after current application, whereas that in 15% NaCl solution initially showed no bond strength reduction after 1 day but exhibited an increase in the bond strength reduction after immersion for 28 days.

Background: Idiopathic condylar resorption (ICR) is an aggressive degenerative disease of the temporomandibular joint that is most frequently observed in teenage girls. However, no specific cause of ICR has been identified. To explore the specific causes of the onset and progression of ICR, we performed a survey-based study on ICR in orthodontic patients and described its subjective symptoms, clinical signs, and condylar morphological features. Methods: A total of 1735 participants were recruited from 2193 orthodontic patients. For each participant, subjective symptoms and clinical signs of temporomandibular disorders (TMDs) were evaluated through clinical examination and a questionnaire. Furthermore, three-dimensional computed tomography (CT) was performed to diagnose ICR. Results: Among the 1735 patients evaluated, ICR was present in two male and ten female patients. All 12 patients had maxillary protrusion and an anterior open bite. Four patients with ICR underwent orthodontic treatment. Based on CT findings, patients with ICR had significantly different condylar sizes and shapes from patients with TMDs alone. Conclusions: The coexistence of intrinsic and extrinsic factors, such as sex-hormone imbalance and a history of orthodontic treatment, might lead to the onset of ICR. We suggest that growing patients suspected of having ICR should undergo CT evaluation because CT findings may precede clinical symptoms and signs.

Following liver transplantation (LT), allograft liver failure can be developed by various causes and requires re-LT. Hence, this study aimed to clarify the characteristics and prognostic factors of patients with allograft liver failure awaiting deceased donor LT (DDLT) in Japan.Of the 2686 DDLT candidates in Japan between 2007 and 2016, 192 adult patients listed for re-LT were retrospectively enrolled in this study. Factors associated with waitlist mortality were assessed using the Cox proportional hazards model. The transplant-free survival probabilities were evaluated using the Kaplan-Meier analysis and log-rank test.The median period from the previous LT to listing for re-LT was 1548 days (range, 4-8449 days). Primary sclerosing cholangitis (PSC), which was a primary indication, showed a higher listing probability for re-LT as compared with other primary etiologies. Recurrent liver disease was a leading cause of allograft failure and was more frequently observed in the primary indication of hepatitis C virus (HCV) infection and PSC in contrast with other etiologies. Multivariate analysis identified the following independent risk factors associated with waitlist mortality: age, Child-Turcotte-Pugh (CTP) score, mode for end-stage liver disease (MELD) score, alanine aminotransferase (ALT), and causes of allograft failure.Recurrent HCV and PSC were major causes of allograft liver failure in Japan. In addition to CTP and MELD scores, either serum ALT levels or causes of allograft failure should be considered as graft liver allocation measures.