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1.
Eur J Orthod ; 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33300988

RESUMO

OBJECTIVE: The primary objective of this study was to quantify the orthodontic tooth movement (OTM) and orthodontically induced root resorption (OIRR) with differential force system in conjunction with minimal surgical insult. MATERIAL AND METHODS: 15-week-old, 48 male Wistar rats were used in the research and were randomly divided into six groups: 1. Group 1 (8 Wistar rats): OTM for 14 days with 8-g force; 2. Group 2 (8 Wistar rats): OTM for 14 days with 25-g force; 3. Group 3 (8 Wistar rats): OTM for 14 days with 100-g force; 4. Group 4 (8 Wistar rats): OTM for 14 days with 8-g force and alveolar decortications (ADs); 5. Group 5 (8 Wistar rats): OTM for 14 days with 25-g force and ADs; 6. Group 6 (8 Wistar rats): OTM for 14 days with 100-g force and ADs. A nickel-titanium spring was used to protract the molar mesially using maxillary incisors as an anchorage. ADs (minimal surgical insult) were done using a hand piece and a round bur, adjacent to the left first maxillary molar on the palatal alveolar bone. After 14 days of OTM, Wistar rats were killed and microfocus computed tomography and histological analysis were performed. RESULTS: The 100-g group showed significant increase (P < 0.05) in OTM. However, with ADs, the OTM was significantly higher (P < 0.05) in 8 and 100 g. In addition, with ADs, there is significant increase (P < 0.05) in OIRR and significant decrease (P < 0.05) in bone volume fraction. Histological quantification of tartrate-resistant acid phosphatase indicated a significant increase (P < 0.05) in the number of osteoclasts with ADs when compared without ADs. CONCLUSIONS: Light force in conjunction with ADs are optimal to accelerate the OTM. Additionally, ADs increases the OIRR.

2.
J World Fed Orthod ; 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33162355

RESUMO

BACKGROUND: The objective of this study was to evaluate the effects of single plane and multiplane rotational errors in yaw, pitch, and roll of the head while recording the lateral cephalogram on CVM (cervical vertebrae maturity) assessment. METHODS: A total of 40 cone-beam computed tomography (CBCT) scans and 360 lateral cephalograms were analyzed for patients with different rotations: Controls (no rotation), Y5 (yaw 5° rotation), Y10 (yaw 10° rotation), R5 (roll 5° rotation), R10 (Roll 10° rotation), P5 (pitch 5° rotation), P10 (pitch 10° rotation), YRP5 (yaw, roll, and pitch 5° rotation), and YRP10 (yaw, roll, and pitch 10° rotation). The C2, C3, and C4 concavity and their base-anterior ratio and posterior-anterior ratio were measured. In addition, maxillomandibular linear parameters, such as effective mandibular length and height, mandibular body length, effective midface length, and maxillomandibular differential, were also evaluated. RESULTS: Y5, Y10, R5, and R10 led to overestimation of CVM in comparison with controls. Multiplane rotations (YRP5 and YRP10) led to more inaccuracies in CVM measurements than single plane rotations; 10° of rotation led to more inaccuracies than 5° of rotation while recording the lateral cephalogram, irrespective of the plane. Yaw rotational errors led to an underestimation of maxillomandibular linear measurements, whereas roll rotational errors led to an overestimation of the measurements; however, there were wide individual variations in the measurements between the different rotations and controls. CONCLUSIONS: Rotational errors lead to overestimation of CVM assessment. Multiplane rotations cause higher inaccuracies than single plane rotations. Increased degree of rotations while capturing the lateral cephalograms lead to more inaccuracies in CVM assessment.

3.
Front Oncol ; 10: 570376, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194663

RESUMO

Background: Curative resection of sigmoid colon and rectal cancer includes "high tie" of the inferior mesenteric artery (IMA). However, IMA ligation compromises blood flow to the anastomosis, which may increase the complication rate. We present preliminary experiences of operative and oncologic outcomes of patients with rectal or sigmoid colon cancer who underwent robotic surgery employing the high dissection and selective ligation technique. Methods: Over May 2013 to April 2017, 113 stage I-III rectal or sigmoid colon cancer patients underwent robotic surgery with the single-docking technique at one institution. We performed D3 lymph node dissection and low-tie ligation of the IMA (i.e., high dissection and selective ligation technique). Clinicopathological features, perioperative parameters, and postoperative outcomes were retrospectively analyzed. Overall survival (OS) and disease-free survival (DFS) were calculated using the Kaplan-Meier method. Results: Sphincter preservation rate was 96.3% in rectal cancer patients. Median number of harvested lymph nodes was 12. Apical nodes were pathologically harvested in 84 (82.4%) patients. R0 resection was performed in 108 (95.6%) patients. Overall complication rate was 17.7%; but most complications were mild and the patients recovered uneventfully. Estimated 5-year OS was 86.1% and 3-year DFS was 79.6% after median follow-up periods of 49.1 months (range, 5.3-85.3). Conclusions: High dissection of the IMA and selective ligation of the major feeding vessel to the sigmoid colon or rectum can be safely performed using da Vinci Surgical System,yielding favorable clinical, and oncologic outcomes in rectal or sigmoid colon cancer treatment.

4.
World J Surg Oncol ; 18(1): 308, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239020

RESUMO

BACKGROUND: The application of minimally invasive surgery in patients with colorectal cancer (CRC) and a history of previous abdominal surgery (PAS) remains controversial. This retrospective study with propensity score matching (PSM) investigated the impact of PAS on robotic-assisted rectal surgery outcomes in patients with locally advanced rectal adenocarcinoma undergoing preoperative concurrent chemoradiotherapy (CCRT). METHODS: In total, 203 patients with locally advanced rectal adenocarcinoma who underwent preoperative CCRT and robotic-assisted rectal surgery between May 2013 and December 2019 were enrolled. Patients were categorized into PAS and non-PAS groups based on the PAS history. The PSM caliper matching method with 1-to-3 matches was used to match PAS patients with non-PAS. RESULTS: Of the 203 enrolled patients, 35 were PAS patients and 168 were non-PAS patients. After PSM, 32 PAS patients and 96 non-PAS patients were included for analysis. No significant between-group differences were noted in the perioperative outcomes, including median console time (165 min (PAS) vs. 175 min (non-PAS), P = 0.4542) and median operation time (275 min (PAS) vs. 290 min (non-PAS), P = 0.5943) after PSM. Postoperative recovery and overall complication rates were also similar (all P > 0.05). Moreover, the between-group differences in pathological or short-term oncological outcomes were also nonsignificant (all P > 0.05). No 30-day postoperative deaths were observed in either group. CONCLUSION: The current results indicate that robotic-assisted surgery is safe and feasible for PAS patients with locally advanced rectal adenocarcinoma undergoing preoperative CCRT. However, future prospective randomized clinical trials are required to verify these findings.

5.
PLoS One ; 15(10): e0240742, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33064768

RESUMO

BACKGROUND: This aim of this study was to evaluate the effects of time interval between the completion of radiotherapy and robotic-assisted surgery on the outcomes among patients with rectal cancer undergoing preoperative concurrent chemoradiotherapy (CCRT). METHODS: In total, 116 patients with stage I-III rectal cancer who underwent preoperative CCRT and robotic-assisted surgery between September 2013 and February 2019 were enrolled. Patients were categorized into two groups based on the time interval: group A (10-12 weeks) and group B (≥ 12 weeks). RESULTS: Among the 116 enrolled patients, 98 (84.5%) had middle and lower rectal cancers. Two (1.7%) patients underwent abdominoperineal resection with a sphincter preservation rate of 98.3%. Thirty-seven (31.9%) patients had a pathologic complete response (pCR). The circumferential resection margin and distal resection margin were positive in 2 (1.7%) and 1 (0.9%) patients, respectively. Therefore, the R0 resection rate was 97.4%. A total of 24 (22.4%) patients experienced postoperative relapse and 12 (10.3%) patients died; these were slightly more common in group B than in group A (28.8% vs 15.8% and 15.3% vs 5.3%, respectively; both P > 0.05); however, this difference was nonsignificant. Three-year disease-free survival (DFS) and overall survival (OS) were 75% and 89%, respectively, among all patients. Non-significant trend of favorable 3-year DFS, 3-year OS, 3-year locoregional control rate and 3-year distant metastasis control rate were observed in group A compared with group B (all P > 0.05). CONCLUSION: Robotic-assisted surgery after a longer interval is safe and feasible for patients with rectal cancer undergoing preoperative CCRT. The present study's results suggested that the time interval of 10-12 weeks can be considered because comparable clinical and perioperative outcomes and preferable oncological outcomes were observed for interval of this length. However, future prospective randomized clinical trials are required to verify the present finding.

6.
Cartilage ; : 1947603520962565, 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33012179

RESUMO

OBJECTIVE: Employ an automated indentation technique, using a commercially available machine, to assess the effect of fibroblast growth factor 2 (FGF2) expression on structural stiffness over the surface of both murine femoral articular cartilage (AC) and temporomandibular joint (TMJ) mandibular condylar cartilage (MCC). DESIGN: Experiments were performed using 3-month-old female homozygote Fgf2KO mice with wild type (WT) littermates. After euthanization, isolated mandibles and hindlimbs were either processed for histology or subjected to automated indentation on a Biomomentum Mach-1 v500csst with a 3-axis motion controller in a phosphate buffered saline bath using a 0.3 mm spherical tip indenter. The effect of indentation depth on normal force was characterized, then structural stiffness was calculated and mapped at multiple positions on the AC and MCC. RESULTS: Automated indentation of the AC and TMJ MCC was successfully completed and was able to demonstrate both regional variation in structural stiffness and differences between WT and Fgf2KO mice. Structural stiffness values for Fgf2KO AC were significantly smaller than WT at both the medial/anterior (P < 0.05) and medial/posterior (P < 0.05) positions. Global Fgf2KO also lead to a decrease in MCC thickness of the TMJ compared with WT (P < 0.05) and increased structural stiffness values for Fgf2KO at both the posterior and anterior location (P < 0.05). CONCLUSIONS: Automated indentation spatially resolved differences in structural stiffness between WT and Fgf2KO tissue, demonstrating FGF2 expression affects femoral AC and TMJ MCC. This quantitative method will provide a valuable approach for functional characterization of cartilage tissues in murine models relevant to knee joint and TMJ health and disease.

8.
Turk J Orthod ; 33(3): 192-196, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32974066

RESUMO

Unilateral posterior crossbite typically presents as a narrow maxillary arch and a broad mandibular arch on the side of the crossbite. Unwanted overexpansion and iatrogenic crossbite may develop as side effects if conventional rapid maxillary expansion is done in such cases. Thus, unilateral expansion of the maxilla with unilateral posterior crossbite can help us avoid these side effects and improve the transverse relationship between the maxillary and mandibular posterior dentition on the affected side only. In this case report, we describe a mini-implant-supported unilateral expansion of the maxillary arch in a patient with a unilateral posterior crossbite.

9.
J Exerc Sci Fit ; 18(3): 142-147, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32514277

RESUMO

Background: Tai-Chi benefits older adults by enhancing balance control and increasing the muscle strength of the lower limbs. However, a complete set of traditional Tai-Chi exercises is sometimes too difficult for beginners. We investigated whether practicing augmented reality-assisted training with selected Tai-Chi movements tailored to the practitioner's ability (selected Tai-Chi, or sTC) is as effective as performing a complete set of Tai-Chi sequences (complete traditional Tai-Chi, or tTC). Methods: In this prospective randomized trial carried out in the Beitou District of Taipei City, Taiwan, community-dwelling adults aged ≥65 and without any debilitating diseases (n = 28) were included. Participants were randomly assigned to the sTC group (n = 14) or the tTC group (n = 14). Participants in the sTC group practiced selected Tai-Chi movements using the augmented reality Tai-Chi training system. Participants of the tTC group were asked to complete the 24-form Yang-style Tai-Chi following the instructions of Tai-Chi masters. Each training session lasted 30 min, with 3 sessions per week for 8 weeks. Pre- and post-intervention evaluations included functional balance tests, comprising the Berg Balance Scale (BBS), Timed Up and Go test (TUG), and Functional Reach Test (FRT), as well as muscle strength measurements of the lower extremities. Results: Pre-intervention evaluations showed significant differences in FRT (p = 0.034) and left hip abductor muscle strength (p = 0.046) between the sTC and tTC groups. After 8 weeks of training, the BBS, TUG, and FRT scores in the sTC group showed significant improvement overall. Although all three functional balance test scores improved in the tTC group, only the improvement in BBS was statistically significant (p = 0.001). After 8 weeks, all muscle strength measurements increased by an average of 3.1 ± 1.0 kgw in the sTC group and 1.6 ± 0.8 kgw in the tTC group. Conclusions: The augmented reality-assisted training with selected Tai-Chi movements, designed based on objective measurements of the practitioner's capability, improved balance control and muscle strength of lower limbs at least as effectively as the complete sequence of traditional Tai-Chi exercises. Trial registration: This study was approved by the Institutional Review Board of National Yang-Ming University (IRB number: 1000087). Written informed consent was obtained from all participants.

10.
Angle Orthod ; 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32134334

RESUMO

OBJECTIVE: To determine the effect of alveolar decortication on orthodontically induced root resorption. MATERIALS AND METHODS: A total of 24 male Wistar rats (14 week old) were used. The rats were randomly divided into one of the following three groups: group 1 (control group), orthodontic tooth movement (OTM) for 2 weeks; group 2, OTM for 2 weeks + two alveolar decortications (2AD); group 3, OTM for 2 weeks + four alveolar decortications (4AD). The first molar was moved mesially for 2 weeks. Micro computed tomography was used to analyze root volume. In addition, histological sections were stained with Tartrate Resistant Acid Phosphatase (TRAP) to quantify the osteoclast number. RESULTS: The buccal root volume in OTM + 4AD group was decreased by 8.92% and 6.11% when compared with the OTM-only group and OTM + 2AD group, respectively. Similarly, the other four root volumes in the OTM + 4AD group was decreased by 8.99% and 5.24% when compared with the OTM-only group and OTM + 2AD group, respectively. There was a decrease in buccal root density in the OTM + 4AD group by 4.66% and 3.56% when compared with the OTM-only group and the OTM + 2AD group, respectively. In addition, there was an increase in the number of osteoclasts by 195.73% and 98.74% in OTM + 4AD group in comparison with the OTM and OTM + 2AD group. CONCLUSIONS: The amount of orthodontically induced root resorption was positively correlated with the extent of surgical injury used to accelerate orthodontic tooth movement.

11.
Eur J Orthod ; 42(4): 371-377, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32065225

RESUMO

BACKGROUND AND OBJECTIVES: Orthodontic relapse is a physiologic process that involves remodelling of the alveolar bone and principle periodontal ligament fibres. Raloxifene is an Food and Drug Administration (FDA)-approved selective oestrogen receptor modulator that inhibits systemic bone loss. In our study, we examined the effects of Raloxifene on alveolar bone modelling and orthodontic relapse in a rodent model. MATERIALS AND METHODS: The efficacy of raloxifene was evaluated in 15-week-old male Wistar rats, 8 in each group (Control, Raloxifene, Raloxifene + 7-day relapse, Raloxifene + 14-day relapse) for a total of 42 days. All animals had 14 days of orthodontic tooth movement with a closed nickel-titanium coil spring tied from incisors to right first molar applying 5-8 gm of force. On the day of appliance removal, impression was taken with silicon material and the distance between first molar and second molar was filled with light-cured adhesive resin cement for retention phase. Raloxifene Retention, Raloxifene Retention + 7D, Raloxifene Retention + 14D groups received 14 daily doses of raloxifene (2.0 mg/kg/day) subcutaneously after orthodontic tooth movement during retention. After 14 days of retention, the retainer was removed and right first molar was allowed to relapse for a period of 14 days. Raloxifene injection continued for the Raloxifene + 14-day relapse group during relapse phase too. Control group received saline injections during retention. Animals were euthanized by CO2 inhalation. The outcome measure included percentage of relapse, bone volume fraction, tissue density, and histology analysis using tartrate-resistant acid phosphatase staining and determining receptor activator of nuclear factor-кB-ligand (RANKL) and osteoprotegerin expression. RESULTS: Raloxifene Retention + 14D group had significantly less (P < 0.05) orthodontic relapse when compared with other groups. There was a significant increase (P < 0.05) in bone volume fraction and tissue density in the Raloxifene Retention + 14D group when compared with other groups. Similarly, there was significant decrease in number of osteoclasts and RANKL expression in Raloxifene Retention + 14D group when compared with Raloxifene Retention + 7D group (P < 0.05). CONCLUSION: Raloxifene could decrease post-orthodontic treatment relapse by decreasing bone resorption and indirectly enhancing bone formation.


Assuntos
Cloridrato de Raloxifeno/farmacologia , Técnicas de Movimentação Dentária , Animais , Remodelação Óssea , Masculino , Dente Molar , Osteoclastos , Ratos , Ratos Wistar , Recidiva
12.
Geroscience ; 42(3): 995-1004, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31993924

RESUMO

Osteoarthritis (OA) of the knee is closely associated with aging; however, little is known about the age-related degeneration in the mandibular condylar cartilage (MCC) of the TMJ. Our objective was to examine whether a correlation exists between aging and degeneration of the MCC of the TMJ. Thirty-two male C57BL/6J wild-type mice were aged to 2, 12, 18, and 25 months old. The mice were euthanized by CO2 inhalation and were dissected and examined by micro-CT and histology. Sagittal sections of the condyles were stained for tartrate-resistant alkaline phosphatase, alkaline phosphatase, safranin O, picrosirius red, and toluidine blue. In addition, immunostaining for BMP2, BMP4, BMP7, PRG4, and MMP13 was performed. Bone volume fraction and tissue density significantly increased with the age of the animals. There was a significant increase in the Osteoarthritis Research Society International histopathological score and mineralization of the noncalcified cartilage in the aged animals. There was a decrease in cartilage thickness, proteoglycan distribution, and cellularity in the aged animals. Additionally, we noted increased picrosirius red staining with the increase in the age of the animals. Our protein expression showed increased BMP2, BMP4, BMP7, and MMP13, whereas there was a decrease in PRG4 expression in the aged animals. As the animal ages, there is decreased proteoglycan secretion, decreased cellularity, decreased cartilage thickness, increased fibrillation, and increased proteolytic activity. A better understanding of the basic mechanisms underlying the degeneration of the MCC in the older animals could provide novel ways to slow the development of OA.

13.
Eur J Orthod ; 42(3): 317-325, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-31147678

RESUMO

BACKGROUND: Accelerating orthodontic tooth movement (OTM) through biologically effective methods, such as increasing osteoclast-mediated alveolar resorption, could effectively shorten treatment time. OBJECTIVE: To evaluate an injectable formulation containing receptor activator of nuclear factor kappa-B ligand (RANKL) on the OTM. MATERIALS AND METHODS: We fabricated a RANKL formulation from 100 µl of 100 µg/ml RANKL adsorbed on 10 mg of poly(lactic acid-co-glycolic acid) microspheres embedded in a 10 wt% aqueous hydroxyethyl cellulose carrier gel. We characterized these formulations for the rate of RANKL release, and then tested for bioactivity using in vitro cell culture. In vivo OTM studies were conducted using 15 week old male Wistar rats for 14 days. We injected the RANKL formulations palatal to the left maxillary first molar and accomplished OTM with a nickel-titanium (NiTi) coil spring applying 5-8 g force. Control groups involved the application of NiTi coil spring with and without placebo formulation. The outcome measure included the distance of tooth movement, bone volume fraction, tissue density, and root volume determined with micro-computed tomography. We determined the amount of osteoclast activity using tartrate-resistant acid phosphatase (TRAP) staining. RESULTS: These formulations were able to sustain the release of RANKL for more than 30 days, and the released RANKL showed a positive effect on mice osteoclast precursor cells (RAW 264.7). Reported injectable RANKL formulations were effective in accelerating OTM compared with other control groups, with 129.2 per cent more tooth movement than no formulation and 71.8 per cent more than placebo formulation, corresponding with a significant increase in the amount of TRAP activity. We did not observe any significant differences in root resorption between the groups. CONCLUSION: Our study shows a significant increase in OTM with injectable formulations containing RANKL.


Assuntos
Osteoclastos , Técnicas de Movimentação Dentária , Animais , Preparações de Ação Retardada , Masculino , Camundongos , Ratos , Ratos Wistar , Microtomografia por Raio-X
14.
Turk J Orthod ; 32(3): 182-189, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31565695

RESUMO

Protraction of posterior teeth to close the spaces in patients with congenitally missing maxillary lateral incisors is challenging. Mini-implants are a reliable source of anchorage for this purpose. This case report demonstrates the application of a T-bar protraction appliance with a palatal mini-implant for en masse protraction of posterior teeth into the lateral incisor space in an adolescent patient. The patient's occlusion and esthetics were significantly improved, and ideal overjet and overbite were obtained after 30 months of treatment. Follow-up records six months after the completion of the treatment displayed stable results.

15.
Am J Transplant ; 19(12): 3250-3262, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31162867

RESUMO

A recurrence of hepatocellular carcinoma (HCC) after living donor liver transplantation (LDLT) is one of the major concerns reflecting the higher mortality of HCC. This study aimed to explore the impact of circulating exosomes on HCC development and recurrence. One-shot transfusion of hepatoma serum to naïve rats induced liver cancer development with gradual elevation of alpha-fetoprotein (AFP), but exosome-free hepatoma serum failed to induce AFP elevation. The microarray analysis revealed miR-92b as one of the highly expressing microribonucleic acids in hepatoma serum exosomes. Overexpression of miR-92b enhanced the migration ability of liver cancer cell lines with active release of exosomal miR-92b. The hepatoma-derived exosomal miR-92b transferred to natural killer (NK) cells, resulting in the downregulation of CD69 and NK cell-mediated cytotoxicity. Furthermore, higher expression of miR-92b in serum exosomes was confirmed in HCC patients before LDLT, and its value at 1 month after LDLT was maintained at a higher level in the patients with posttransplant HCC recurrence. In summary, we demonstrated the impact of circulating exosomes on liver cancer development, partly through the suppression of CD69 on NK cells by hepatoma-derived exosomal miR-92b. The value of circulating exosomal miR-92b may predict the risk of posttransplant HCC recurrence.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Transplante de Fígado/efeitos adversos , MicroRNAs/genética , Recidiva Local de Neoplasia/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Animais , Carcinoma Hepatocelular/etiologia , Proliferação de Células , Exossomos , Feminino , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas Experimentais/diagnóstico , Neoplasias Hepáticas Experimentais/etiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Recidiva Local de Neoplasia/etiologia , Complicações Pós-Operatórias/etiologia , Ratos
16.
Cartilage ; : 1947603519833146, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30897936

RESUMO

OBJECTIVE: To characterize the long-term effects of intermittent parathyroid hormone (I-PTH) on the mandibular condylar cartilage (MCC) and subchondral bone of the temporomandibular joint, in vivo and in vitro. MATERIALS AND METHODS: For the in vivo experiments, sixteen 10-week-old mice were divided into 2 groups: (1) I-PTH ( n = 8)-subcutaneous daily injection of PTH; (2) control group ( n = 8)-subcutaneous daily injection of saline solution. Experiments were carried out for 4 weeks. Mice were injected with calcein, alizarin complexone, and cell proliferation marker before euthanasia. For the in vitro experiments, primary chondrocyte cultures from the MCC of eight 10-week-old mice were treated with I-PTH for 14 days. RESULTS: There was a significant increase in bone volume, tissue density, mineral deposition, osteoclastic activity, cell proliferation in the cartilage, and cartilage thickness in the I-PTH-treated mice when compared with the control group. In addition, immunohistochemistry in cartilage revealed that I-PTH administration led to an increase in expression of vascular endothelial growth factor and to a decreased expression of sclerostin, matrix metallopeptidase 13, and aggreganase-1 (ADAM-TS4). Quantitative polymerase chain reaction analysis of the I-PTH-treated chondrocytes revealed significantly decreased relative expression of collagen type X ( Col10a1), alkaline phosphatase ( Alp), and Indian Hedgehog ( Ihh) and remarkable increased expression of Sox9, fibroblast growth factor 2 ( Fgf2), and proteoglycan 4 ( Prg4). CONCLUSION: I-PTH administration causes anabolic effects at the subchondral region of the mandibular condyle while triggers anabolic and protective effects at the MCC.

17.
Eur J Orthod ; 41(6): 601-608, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30828725

RESUMO

OBJECTIVE: The primary objective of this study was to investigate how the extent of surgical insult affects the orthodontic tooth movement (OTM) and the alveolar bone modelling and remodelling in a rodent model. MATERIAL AND METHODS: 15-week-old male Wistar rats were used in the research and they were randomly divided into three treatment groups: (1) OTM only (N = 8); (2) OTM + 2 alveolar decortication (AD) (less surgical insult) (N = 8); and (3) OTM + 4 AD (more surgical insult) (N = 8). A nickel-titanium spring delivering 5-8 g of force was used to protract the molar mesially using maxillary incisors as an anchorage. AD was done using a hand piece and a round bur, adjacent to the left first maxillary molar on the palatal alveolar bone. After 14 days of OTM Wistar rats were killed and microfocus computed tomography and histological analysis were performed. RESULTS: The OTM + 4AD group presented with a significant increase (P < 0.05) in the rate of tooth movement when compared to OTM + 2AD group and OTM only group. In addition, the OTM + 4AD group had a significant decrease in bone volume and tissue density (P < 0.05) and a significant increase (P < 0.05) in the trabecular spacing and trabecular thickness when compared to OTM only. Histological quantification of tartrate-resistant acid phosphatase indicated a significant percent increase (P < 0.05) in OTM + 4AD group, when compared to OTM + 2AD and OTM only group. RESULTS: Increased surgical insult increases the rate of OTM. Additionally, increased surgical insult decreases the bone volume and the tissue density.


Assuntos
Remodelação Óssea , Técnicas de Movimentação Dentária/efeitos adversos , Animais , Masculino , Dente Molar/cirurgia , Osteoclastos , Ratos , Ratos Wistar , Fosfatase Ácida Resistente a Tartarato
18.
Am J Orthod Dentofacial Orthop ; 155(3): 421-431, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30826045

RESUMO

Short root anomaly (SRA) is a rare familial dental condition that is often misdiagnosed. Orthodontic treatment of patients with SRA is challenging because it is difficult to diagnose, it may be accompanied by other dental anomalies, and it has been reported to contribute to additional susceptibility to root resorption during orthodontic treatment. In this article, we describe a methodical and evidence-based means of diagnosing and orthodontically managing a patient with SRA. The patient had additional challenges, including impacted and ectopic teeth. An individualized treatment plan that incorporated efficient and effective mechanics led to a well seated occlusion and an esthetic smile.


Assuntos
Extrusão Ortodôntica/métodos , Ortodontia Corretiva/métodos , Erupção Ectópica de Dente/diagnóstico por imagem , Erupção Ectópica de Dente/terapia , Raiz Dentária/anormalidades , Raiz Dentária/diagnóstico por imagem , Dente Impactado/terapia , Adolescente , Cefalometria , Tomografia Computadorizada de Feixe Cônico , Estética Dentária , Feminino , Humanos , Radiografia Panorâmica , Sorriso , Dente Impactado/diagnóstico por imagem
19.
Transl Oncol ; 12(3): 502-512, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30594039

RESUMO

BACKGROUND: To evaluate the efficacy and toxicities of regorafenib plus irinotecan, dose-escalated on the basis of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) genotyping, in previously heavily treated metastatic colorectal cancer (mCRC) and the prognostic values of EGFR expression, KRAS mutations, and tumor sidedness. METHODS: Forty-one patients with mCRC with disease progression after treatment with fluoropyrimidines, oxaliplatin, irinotecan, anti-VEGF, and anti-EGFR MoAbs were subjected to UGT1A1 genotyping and received regorafenib combined with FOLFIRI with dose-escalated irinotecan. RESULTS: The median follow-up period was 10.0 months (1.3-23.5 months). The overall disease control rate was 58.5%, whereas the median progression-free survival (PFS) and overall survival (OS) were 6.0 months and 12.0 months, respectively. KRAS mutations were significantly associated with positive EGFR expression (P = .026). KRAS mutations significantly correlated with a shorter OS than KRAS wild-type (6.0 vs. 14.4 months, P = .014) but had no significant association with PFS. Positive EGFR expression had an inverse correlation with PFS (2.5 vs. 14.0 months, P = .039) and OS (9.6 vs. 19.7 months, P = .044). Moreover, left-sided tumors associated with superior PFS (2.0 vs. 7.0 months, P < .0001) and OS (4.0 vs. 13.0 months, P < .0001), and tumor sidedness was an independent prognostic factor by the multivariate analysis. CONCLUSION: Regorafenib and FOLFIRI concomitant therapy with dose-escalated irinotecan seemed to be potentially practicable with satisfactory oncological results. KRAS mutations and EGFR expression might be predictors of poor oncological outcomes; however, left-sided mCRCs would be more beneficial for concomitant regorafenib and FOLFIRI therapy.

20.
J Vis Exp ; (137)2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30102279

RESUMO

A proper understanding of the force system created by various orthodontic appliances can make treatment of patients efficient and predictable. Reducing the complicated multi-bracket appliances to a simple two-bracket system for the purpose of force system evaluation will be the first step in this direction. However, much of the orthodontic biomechanics in this regard is confined to 2D experimental studies, computer modeling/analysis or theoretical extrapolation of existing models. The objective of this protocol is to design, construct and validate an in vitro 3D model capable of measuring the forces and moments generated by an archwire with a V-bend placed between two brackets. Additional objectives are to compare the force system generated by different types of archwires among themselves and to previous models. For this purpose, a 2 x 4 appliance representing a molar and an incisor has been simulated. An orthodontic wire tester (OWT) is constructed consisting of two multi-axis force transducers or load cells (nanosensors) to which the orthodontic brackets are attached. The load cells are capable of measuring the force system in all the three planes of space. Two types of archwires, stainless-steel and beta-titanium of three different sizes (0.016 x 0.022 inch, 0.017 x 0.025 inch and 0.019 x 0.025 inch), are tested. Each wire receives a single vertical V-bend systematically placed at a specific position with a predefined angle. Similar V-bends are replicated on different archwires at 11 different locations between the molar and incisor attachments. This is the first time an attempt has been made in vitro to simulate an orthodontic appliance utilizing V-bends on different archwires.


Assuntos
Teste de Materiais/métodos , Desenho de Aparelho Ortodôntico/métodos , Fios Ortodônticos/estatística & dados numéricos , Humanos , Propriedades de Superfície
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