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1.
J Prosthet Dent ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38036320

RESUMO

STATEMENT OF PROBLEM: Progressive peri-implant marginal bone loss and peri-implantitis have become a growing problem, but cross-sectional studies on their prevalence and risk factors are sparse. PURPOSE: The purpose of this cross-sectional clinical study was to investigate the prevalence of peri-implant marginal bone loss (MBL) and to identify systemic and local risk factors. MATERIAL AND METHODS: All adult patients who had received dental implants at the National Taiwan University Hospital (NTUH) during 2009 or 2010 were included. Their medical records were collected from the NTUH-integrative Medical Database. Consecutive follow-up radiographs were accessed for severity of MBL. The influence of each factor on MBL was estimated by using generalized estimating equations (GEEs). RESULTS: A total of 732 participants with 1873 implants were analyzed (mean follow-up: 5.30 years). The prevalence of MBL was 59.15% at the individual level and 49.55% at the implant level. The risk indicators identified for the presence of MBL were follow-up period of more than 2 years, diagnosis of diabetes within 12 months, radiation therapy (2 years after implant placement), implant location at maxillary canine (compared with mandibular molar), and implants from the Nobel Biocare brands (Brånemark System and NobelActive). A second multivariate GEE model confirmed the association of progressive MBL with implant location at the maxillary canine and mandibular incisor and implant brand or design. CONCLUSIONS: The identified risk indicators for MBL were longer follow-up period, diagnosis of diabetes, radiation therapy, implant location at maxillary canine, and implant brand or design.

2.
J Formos Med Assoc ; 121(7): 1295-1301, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34593273

RESUMO

BACKGROUND/PURPOSE: Crestal bone stability, implant rigidity and occlusal loading are issues with small-diameter implants. This article demonstrates the use of two small-diameter implants replacing a missing wide edentulous site and discusses factors that may affect bone changes. METHODS: Patients who wanted to restore an edentulous space measuring from 12 to 14 mm wide in the posterior region were offered an alternative treatment option, using two narrow or regular-diameter implants instead of one wide implant. In the study, the crestal bone stability of 12 implants in 6 edentulous sites was assessed by cone beam CTs and periapical radiographs in follow-up visits for up to 4 years. RESULTS: The bone level of all the implants was stable at buccal, lingual, mesial and distal sites, with mean values < 1 mm. The average buccal bone thickness was 1.15 ± 1.07 mm and lingual was 1.86 ± 0.89 mm, meaning that implants were surrounded by a sufficient amount of bone. The good treatment outcome may be attributed to the capability of fabricating better emergence profiles, angles (Mean: 20.67 ± 7.82° at the mesial and 20.25 ± 8.23° at the distal site) and cleansable embrasures of prostheses which are key to maintaining good oral hygiene and implant health. CONCLUSION: Using two narrow or regular-diameter implants to replace a single edentulous site measured around 12-14 mm wide in posterior region seemed to be a feasible treatment option. It is especially suitable for sites with ridge atrophy and/or patients suffering from systemic diseases.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/cirurgia , Seguimentos , Humanos , Mandíbula , Próteses e Implantes , Resultado do Tratamento
3.
Int J Mol Sci ; 23(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35008984

RESUMO

In this study, we fabricated gelatin/nano-hydroxyapatite/metformin scaffold (GHMS) and compared its effectiveness in bone regeneration with extraction-only, Sinbone, and Bio-Oss Collagen® groups in a critical size rat alveolar bone defect model. GHMS was synthesized by co-precipitating calcium hydroxide and orthophosphoric acid within gelatin solution, incorporating metformin, and cross-linked by microbial transglutaminase. The morphology, characterization, and biocompatibility of scaffold were examined. The in vitro effects of GHMS on osteogenic gene and protein expressions were evaluated. In vivo bone formation was assessed in a critical size rat alveolar bone defect model with micro-computed tomography and histological examination by comparing GHMS with extraction-only, Sinbone, and Bio-Oss Collagen®. The synthesized GHMS had a highly interconnected porous structure with a mean pore size of 81.85 ± 13.8 µm. GHMS exhibited good biocompatibility; promoted ALPL, RUNX2, SP7, BGLAP, SPARC and Col1a1 gene expressions; and upregulated the synthesis of osteogenic proteins, including osteonectin, osteocalcin, and collagen type I. In critical size rat alveolar bone defects, GHMS showed superior bone regeneration compared to extraction-only, Sinbone, and Bio-Oss Collagen® groups as manifested by greater alveolar ridge preservation, while more bone formation with a lower percentage of connective tissue and residual scaffold at the defect sites grafted with GHMS in histological staining. The GHMS presented in this study may be used as a potential bone substitute to regenerate alveolar bone. The good biocompatibility, relatively fast degradation, interconnected pores allowing vascularization, and higher bioactivity properties of the components of the GHMS (gelatin, nHA, and metformin) may contribute to direct osteogenesis.


Assuntos
Regeneração Óssea , Durapatita , Gelatina , Regeneração Tecidual Guiada , Metformina/administração & dosagem , Nanocompostos , Alicerces Teciduais , Animais , Materiais Biocompatíveis/química , Biomarcadores , Fenômenos Químicos , Durapatita/química , Gelatina/química , Regeneração Tecidual Guiada/métodos , Imuno-Histoquímica , Minerais , Modelos Animais , Nanocompostos/química , Nanocompostos/ultraestrutura , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Ratos , Engenharia Tecidual , Alicerces Teciduais/química , Microtomografia por Raio-X
4.
J Prosthodont ; 31(8): 681-688, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35770466

RESUMO

PURPOSE: To analyze the tissue morphology around implant-supported prostheses by digital technology and to evaluate the effect of prosthetic contours on the changes in tissues following the free gingiva graft procedure. MATERIAL AND METHODS: A total of 53 implants in 32 patients receiving free gingiva grafts were selected. These had previously presented insufficient keratinized mucosa width (KMW). At the follow-up visits (mean: 16.66 ± 9.97 months), the implant position and tissue condition were documented with an oral scanner. Vertical soft tissue thickness (VT), measured from the implant-abutment connection to the marginal tissues, and horizontal soft tissue thickness (HT), at the level of the platform, were calculated. The VT, HT, and emergence angle (EA) of prostheses were assessed by 3Shape analyzing software. The final KMW was measured by clinical assessment. Marginal bone loss (MBL) was calculated in the follow-up bitewing radiographs. RESULTS: The mean VT in the study was 2.65 ± 0.75 mm at the mid-buccal sites, 3.74 ± 1.22 mm at the mesial, 3.16 ± 1.08 mm at the distal, and 2.53 ± 0.92 at the mid-lingual aspects. The mid-buccal HT was 1.45 ± 0.53 mm while the mid-lingual was 1.05 ± 0.43 mm (p = 0.008). Interestingly, prostheses with mid-buccal EA > $\; > \;$ 30° exhibited slightly lower VT, but higher HT, than the ones with EA ≤ $\; \le \;$ 30°. Prostheses with proximal EA > 30° displayed slightly more MBL, compared to prostheses with EA ≤ $\; \le \;$ 30°. The mean KMW was 4.08 ± 1.10 mm. CONCLUSIONS: Free gingival grafting is a predictable treatment approach to augmenting soft tissue 3-dimensionally. Prostheses with EA ≤ $\; \le \;$ 30° were preferable for preserving the maximal VT and maintaining crestal bone stability.


Assuntos
Implantes Dentários , Dente , Humanos , Gengiva
5.
J Formos Med Assoc ; 119(4): 869-878, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31331705

RESUMO

This report provides three-phase concept for treating skeletal Class III growing patients with severe space deficiency. Three cases are presented. All had received miniplate-anchored facemask treatment and followed till near completion of growth. Infrazygomatic miniplates were used for both facemask protraction and distalization of the dentition to relieve crowding. With the aid of bone-anchored facemask, maxillary protraction may be continued independent of the orthodontic tooth movement even in late postpubertal growth peak stage. With cephalometric superimpositions using the structural method, we have demonstrated how vertical dental change could affect the skeletal changes and overall clinical outcomes. The persistent mandibular growth during pubertal growth spurt plays a main role in decreasing the effects of maxillary protraction. To keep up with the mandibular growth, we recommend using skeletally anchored facemask long-term till the end of growth spurt. Applying maxillary protraction from infrazygomatic miniplates exposed at the molar area has the merits that it avoids unwanted palatal rotation and that the miniplates maybe used as orthodontic anchorage when indicated. We emphasize the importance of planning the treatment contemplating the skeletal developmental stage and the completion of dental arches. This prolonged orthopedic treatment may contribute to greater long-term effects and stability.


Assuntos
Aparelhos de Tração Extrabucal , Má Oclusão Classe III de Angle/terapia , Desenho de Aparelho Ortodôntico , Técnicas de Movimentação Dentária/instrumentação , Cefalometria/métodos , Criança , Feminino , Humanos , Masculino , Mandíbula/patologia , Maxila/patologia , Dente Molar/patologia , Procedimentos de Ancoragem Ortodôntica/instrumentação
6.
J Formos Med Assoc ; 119(1 Pt 3): 420-429, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31387841

RESUMO

BACKGROUND/PURPOSE: Alveolar bone loss following peri-implantitis remains a clinical challenge. We aimed to design a novel bioactive dental implant to accommodate the large bone defect caused by removal of previously failed implant. METHODS: Bio-ActiveITRI dental implant was manufactured with laser-sintered additive 3D printing technique. A 7.5 mm diameter × 7.0 mm depth osteotomy defect was created at the lateral aspect of distal femur of 20 New Zealand white rabbits to simulate the bony defect after removal of failed dental implant. One side of distal femurs was randomly selected for the commercially pure titanium NobelActive™ implant (control group) and the other side with Bio-ActiveITRI Ti6Al4V porous dental implant (ITRI group). Animals were sacrificed at 4, 8 and 12 weeks after the implants' insertion. The samples were processed for gross morphological analysis, radiographic examination, micro-CT evaluation, and mechanical testing. RESULTS: In histomorphometrical evaluation and micro-CT analysis, active new bone formation and good osseointegration within the ITRI implants were observed at the bone gap surrounding the dental implants. The biomechanical parameters in the Bio-ActiveITRI dental implants were significantly higher than those of the commercially control samples. For the Bio-ActiveITRI dental implants, the trabecular thickness decreased, while the trabecular separation and total porosity increased from the prescribed 1-month to 3-month time points; reflecting the natural remodeling of surrounding bony tissue in the Bio-ActiveITRI dental implants. CONCLUSION: The novel porous structured Bio-ActiveITRI dental implants may have a great potential for the prosthetic reconstruction where bone support is compromised after removal of a previously failed implant.


Assuntos
Implantes Dentários , Fêmur/cirurgia , Lasers , Osseointegração/fisiologia , Impressão Tridimensional , Titânio/química , Animais , Teste de Materiais , Porosidade , Coelhos , Propriedades de Superfície , Titânio/efeitos da radiação , Microtomografia por Raio-X
7.
Int J Paediatr Dent ; 30(2): 156-170, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31680340

RESUMO

BACKGROUND: Obstructive sleep apnoea (OSA) affects many children, and adenotonsillar hypertrophy is the most common cause of paediatric OSA. AIM: Despite the growing treatment options, there is no comprehensive comparison of all interventions. We aimed to compare and rank the effectiveness of various treatments in a network meta-analysis. DESIGN: Literature was searched from inception to 13 May 2018 for paediatric OSA with adenotonsillar hypertrophy. The outcomes were the changes in apnoea-hypopnea index (AHI), oxyhaemoglobin desaturation index (ODI), and lowest arterial oxygen saturation (SaO2 ). Frequentist approach to network meta-analysis was used. Treatment hierarchy was summarized according to the surfaces under the cumulative ranking curves. RESULTS: Fourteen trials comprising 1064 paediatric OSA participants evaluating ten interventions (adenotonsillectomy, adenotonsillectomy + pharyngoplasty, adenotonsillotomy, antimicrobial therapy, steroids, leukotriene receptor antagonists [LTRAs], steroids + LTRAs, rapid maxillary expansion [RME], placebo, and no treatment) were identified for network meta-analysis. In terms of effectiveness in AHI reduction, surgical approach was still the most effective intervention than no treatment. RME was one of the most effective interventions to improve lowest SaO2 . No comparisons showed statistical significance in reducing ODI. CONCLUSIONS: Irrespective of the intervention used, complete resolution of OSA was not achieved in most trials.


Assuntos
Apneia Obstrutiva do Sono , Tonsilectomia , Adenoidectomia , Criança , Humanos , Metanálise em Rede , Técnica de Expansão Palatina
8.
J Formos Med Assoc ; 118(4): 750-765, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29523457

RESUMO

Many treatments have been proposed for adult obstructive sleep apnea (OSA), but no comprehensive comparison of all interventions has been performed. We aimed to compare and rank the effectiveness of all minimally invasive treatments for adult OSA in a systematic review and network meta-analysis. Literature was searched within Ovid MedLine, EMBASE Classic+Embase, Cochrane library, and Cochrane Database of Systematic Reviews from inception to Aug 9th, 2016 for randomized controlled trials comparing minimally invasive treatments for adult OSA. The outcomes were the changes in apnea-hypopnea index (AHI) and Epworth sleepiness scale (ESS). Frequentist approach to network meta-analysis was used and treatment hierarchy was summarized according to the surfaces under the cumulative ranking curves. Eighty-nine randomized controlled trials comprising 6346 adult OSA participants and comparing 18 different interventions were included. In comparison with no treatment, positive airway pressure (PAP) was most effective in reducing AHI (23.28 [weighted mean difference]; 95% confidence interval: 19.20-27.35). PAP was ranked first followed by mandibular advancement device (MAD) in reducing AHI. Exercise was ranked first followed by cervico-mandibular support collar in reducing ESS. Considering the effectiveness in reducing both AHI and ESS, PAP was ranked the best, followed by MAD and positional therapy, while lifestyle modification alone was the least effective intervention. Interventions that are highly effective in reducing objective laboratory-derived AHI do not demonstrate equivalent effectiveness in improving patients' subjective sleepiness. Future improvement of the interventions is necessary to simultaneously improve both objective and subjective outcomes.


Assuntos
Avanço Mandibular/instrumentação , Apneia Obstrutiva do Sono/terapia , Adulto , Exercício Físico , Humanos , Metanálise em Rede , Respiração com Pressão Positiva , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
J Prosthet Dent ; 122(6): 503-509, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31027949

RESUMO

Anterior implant restoration is one of the most challenging restorative procedures, especially for sites with vertical and/or horizontal hard and soft tissue deformities. Orthodontic extrusion before implant placement may be the best means of overcoming vertical deficiencies. This article describes a modification to the standard technique, involving staged orthodontic extrusion and buccal root torque. The main advantage of this modification is that it encourages bone and soft tissue development, thereby allowing the patient to receive immediate or early implant treatment. A clinical procedure is presented to illustrate the modified technique that resulted in an esthetically pleasing and stable 5-year outcome.


Assuntos
Implantes Dentários para Um Único Dente , Carga Imediata em Implante Dentário , Implantação Dentária Endóssea , Seguimentos , Humanos , Extrusão Ortodôntica , Raiz Dentária , Torque
10.
J Oral Rehabil ; 45(12): 939-947, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30133810

RESUMO

OBJECTIVE: The aim of this study was to analyse morphological changes in the upper airways in patients with anterior open bite treated with temporary anchorage devices for intrusion of upper posterior teeth. MATERIALS AND METHODS: Twelve nonobese (body mass index: <25) anterior open bite patients between the ages of 19 and 44 years (mean age: 22.83 ± 8.19 years) were recruited for this study. Cephalometric radiographs and magnetic resonance imaging (MRI) scans before and after anterior bite closure without bracketing on anterior teeth were used to measure the upper airway, which was divided into retropalatal and retroglossal regions. RESULTS: The mandibular plane angle and lower facial height were significantly reduced by intrusion of the upper posteriors and autorotation of the mandible. The retroglossal airway width (AW2) and retroglossal area (RG area) measured on cephalometric radiographs both increased significantly after treatment. Retroglossal volume increased and the retroglossal width/length ratio decreased significantly in MRI analysis. All other measurements were not significantly changed. However, no statistically significant correlations were observed between all measurements in 2D and 3D images, with the exception of the AW2 linear measurement in 2D images correlating with the AP length in MRI axial view images (r = 0.56, P = 0.0430). CONCLUSION: Counterclockwise rotation of the mandible after anterior open bite closed using orthodontic treatment changed the airway morphology. Retroglossal volume significantly increased and the airway shape became less elliptical after bite closure.


Assuntos
Adaptação Fisiológica/fisiologia , Cefalometria , Imageamento por Ressonância Magnética , Dente Molar/patologia , Mordida Aberta/fisiopatologia , Orofaringe/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica , Adulto , Feminino , Humanos , Imageamento Tridimensional , Masculino , Mandíbula/patologia , Maxila/patologia , Mordida Aberta/diagnóstico por imagem , Orofaringe/fisiopatologia , Estudos Prospectivos , Adulto Jovem
11.
BMC Infect Dis ; 17(1): 516, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28743235

RESUMO

BACKGROUND: When bacteria colony persist within a biofilm, suitable drugs are not yet available for the eradication of biofilm-producing bacteria. The aim of this study is to study the effect of magnetic nano-particles-induced hyperthermia on destroying biofilm and promoting bactericidal effects of antibiotics in the treatment of osteomyelitis. METHODS: Sixty 12-weeks-old male Wistar rats were used. A metallic 18G needle was implanted into the bone marrow cavity of distal femur after the injection of Methicillin-sensitive Staphylococcus aureus (MSSA). All animals were divided into 5 different treatment modalities. The microbiological evaluation, scanning electron microscope examination, radiographic examination and then micro-CT evaluation of peri-implant bone resorption were analyzed. RESULTS: The pathomorphological characteristics of biofilm formation were completed after 40-days induction of osteomyelitis. The inserted implants can be heated upto 75 °C by magnetic heating without any significant thermal damage on the surrounding tissue. We also demonstrated that systemic administration of vancomycin [VC (i.m.)] could not eradicate the bacteria; but, local administration of vancomycin into the femoral canal and the presence of magnetic nanoparticles hyperthermia did enhance the eradication of bacteria in a biofilm-based colony. In these two groups, the percent bone volume (BV/TV: %) was significantly higher than that of the positive control. CONCLUSIONS: For the treatment of chronic osteomyelitis, we developed a new modality to improve antibiotic efficacy; the protection effect of biofilms on bacteria could be destroyed by magnetic nanoparticles-induced hyperthermia and therapeutic effect of systemic antibiotics could be enhanced.


Assuntos
Antibacterianos/farmacologia , Hipertermia Induzida/métodos , Osteomielite/terapia , Infecções Relacionadas à Prótese/terapia , Infecções Estafilocócicas/terapia , Animais , Biofilmes , Hipertermia Induzida/instrumentação , Nanopartículas de Magnetita , Masculino , Staphylococcus aureus Resistente à Meticilina , Osteomielite/microbiologia , Ratos Wistar , Infecções Estafilocócicas/microbiologia , Resultado do Tratamento , Vancomicina/farmacologia
12.
J Formos Med Assoc ; 116(2): 107-113, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26922429

RESUMO

BACKGROUND/PURPOSE: Transforming growth factor (TGF)-ß is a key regulator in the pathogenesis of oral submucous fibrosis (OSF). Early growth response (Egr)-1 is essential for fibrotic responses to TGF-ß. Because TGF-ß signaling is cell-type- and context-dependent, we investigated the signaling involved in TGF-ß-induced Egr-1 in primary human buccal mucosal fibroblasts (BMFs). METHODS: TGF-ß-induced Egr-1 and its signaling were assessed by western blotting in BMFs. Egr-1 small interfering RNA was used to define the role of Egr-1 on TGF-ß-induced mRNAs of the α1- and α2-chains of type I collagen (COL1A1 and COL1A2) and acid-soluble collagen production (via Sircol collagen assay). The effects of epigallocatechin-3-gallate (EGCG) on TGF-ß-induced Egr-1 protein and acid-soluble collagen were also evaluated. RESULTS: TGF-ß1 stimulated Egr-1 production in BMFs. Pretreatment with PD98059, SP600125, SB431542, and SIS3, but not SB203580, significantly reduced TGF-ß1-induced Egr-1 protein expression. Genetic targeting of Egr-1 completely inhibited TGF-ß1-induced type I collagen mRNAs and collagen protein expression. EGCG fully inhibited TGF-ß1-induced Egr-1 and TGF-ß1-stimulated production of acid-soluble collagens. CONCLUSION: We conclude that activin receptor-like kinase (ALK)5, Smad3, extracellular signal-regulated kinase, and c-Jun N-terminal kinase are involved in the TGF-ß1-induced Egr-1 protein production in BMFs. Egr-1 mediates TGF-ß1-induced COL1A1 and COL1A2 mRNA expression and acid-soluble collagen production in BMFs. EGCG can block TGF-ß1-induced collagen production by attenuating Egr-1 expression in BMFs. Egr-1 is a key mediator in TGF-ß1-induced pathogenesis of OSF. EGCG may be useful in the prevention or treatment of OSF.


Assuntos
Catequina/análogos & derivados , Colágeno Tipo I/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Fibroblastos/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Antracenos/farmacologia , Benzamidas/farmacologia , Catequina/farmacologia , Células Cultivadas , Dioxóis/farmacologia , Proteína 1 de Resposta de Crescimento Precoce/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Flavonoides/farmacologia , Humanos , Mucosa Bucal/citologia , Fibrose Oral Submucosa/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos
13.
Clin Oral Investig ; 19(6): 1463-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25467236

RESUMO

OBJECTIVES: Triethylene glycol dimethacrylate (TEGDMA) is a common component of resin-based dental composites and endodontic sealers. TEGDMA induces apoptosis in several types of cells. However, the mechanisms are not completely understood. The aim of this study was to investigate the mechanisms underlying TEGDMA-induced apoptosis in human embryonic palatal mesenchymal (HEPM) pre-osteoblasts and primary human dental pulp (HDP) cells. MATERIAL AND METHODS: Cell viability was examined after TEGDMA treatment. Cell cycle progression was checked by flow cytometry. Apoptotic cells were evaluated using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling assay and visualized by fluorescence microscopy. Western blot analyses were performed to determine expressions of apoptosis-related proteins. The production of reactive oxygen species (ROS) was detected using flow cytometry. NADPH oxidase 4 (NOX4) expression levels were investigated using real-time quantitative polymerase chain reaction and Western blot analyses. RESULTS: TEGDMA increased cytosol cytochrome c levels and activated caspase-9 in HEPM and HDP cells. TEGDMA decreased the expression of anti-apoptotic protein Bcl-XL. TEGDMA-induced apoptosis was inhibited by caspase-9-specific inhibitor, anti-oxidants, NOX inhibitor, NOX4 inhibitor, and NOX4 small interfering RNA (siRNA). TEGDMA increased ROS production and upregulated NOX4 mRNA and protein expression. TEGDMA-induced intracellular ROS production was inhibited by NOX inhibitor and NOX4 inhibitor. CONCLUSIONS: We demonstrate significant involvement of NOX4 in the TEGDMA-induced ROS. NOX4-derived ROS subsequently induces mitochondrial cytochrome c release leading to apoptosis through activation of the intrinsic apoptotic pathway. CLINICAL RELEVANCE: NOX4 may be a potential target for strategies to prevent or ameliorate the TEGDMA-induced toxicity in HEPM and HDP cells.


Assuntos
Polpa Dentária/citologia , NADPH Oxidase 4/fisiologia , Osteoblastos/efeitos dos fármacos , Palato/citologia , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Ciclo Celular , Sobrevivência Celular , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Palato/embriologia , Reação em Cadeia da Polimerase em Tempo Real
14.
J Formos Med Assoc ; 114(11): 1122-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25260551

RESUMO

BACKGROUND/PURPOSE: The aim of this study is to comprehensively analyze the potential factors affecting the failure rates of three types of mini-implants used for orthodontic anchorage. METHODS: Data were collected on 727 mini-implants (miniplates, predrilled titanium miniscrews, and self-drilling stainless steel miniscrews) in 220 patients. The factors related to mini-implant failure were investigated using a Chi-square test for univariate analysis and a generalized estimating equation model for multivariate analysis. RESULTS: The failure rate for miniplates was significantly lower than for miniscrews. All types of mini-implants, especially the self-drilling stainless steel miniscrews, showed decreased stability if the previous implantation had failed. The stability of predrilled titanium miniscrews and self-drilling stainless steel miniscrews were comparable at the first implantation. However, the failure rate of stainless steel miniscrews increased at the second implantation. The univariate analysis showed that the following variables had a significant influence on the failure rates of mini-implants: age of patient, type of mini-implant, site of implantation, and characteristics of the soft tissue around the mini-implants. The generalized estimating equation analysis revealed that mini-implants with miniscrews used in patients younger than 35 years, subjected to orthodontic loading after 30 days and implanted on the alveolar bone ridge, have a significantly higher risk of failure. CONCLUSION: This study revealed that once the dental surgeon becomes familiar with the procedure, the stability of orthodontic mini-implants depends on the type of mini-implant, age of the patient, implantation site, and the healing time of the mini-implant. Miniplates are a more feasible anchorage system when miniscrews fail repeatedly.


Assuntos
Processo Alveolar/cirurgia , Implantes Dentários/normas , Análise do Estresse Dentário , Falha de Equipamento/estatística & dados numéricos , Procedimentos de Ancoragem Ortodôntica/normas , Adulto , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Análise Multivariada , Estudos Retrospectivos , Taiwan
15.
J Formos Med Assoc ; 113(7): 447-53, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24961187

RESUMO

BACKGROUND/PURPOSE: Mechanical loading plays an important role in regulating bone formation and remodeling. Relevant mechanical stretching can increase the proliferation and differentiation of osteoblastic cells in vitro. However, little is known about the effects of supraphysiological high-level mechanical stretching on the growth and cell cycle progression of osteoblastic cells. METHODS: Osteoblast-like MG-63 cells were seeded onto flexible-bottomed plates and subjected to cyclic mechanical stretching (15% elongation, 0.5 Hz) for 24 and 48 hours in a Flexercell FX-4000 strain unit. Cellular activities were measured by an assay based on the reduction of the tetrazolium salt, 3-[4,5-dimethyldiazol-2-yl]-2,5-diphenyl tetra-zolium bromide (MTT). The number of viable cells was also determined by the trypan blue dye exclusion technique. Cell cycle progression was checked by flow cytometry. mRNA expressions of apoptosis- and cell cycle-related genes (Bcl2, Bax, cdc2, cdc25C, and cyclin B1) were analyzed using an RT-PCR technique. RESULTS: The number of viable cells significantly decreased in osteoblast-like MG-63 cells subjected to cyclic mechanical stretching for 24 or 48 hours. The MTT activity of stretched cells did not change at 24 hours, whereas a significant decrease was noted at 48 hours in comparison to the unstretched controls. The flow cytometry showed that mechanical stretching induced S-phase cell cycle arrest. Furthermore, exposure to mechanical stretching led to apoptotic cell death, as shown by the increase in the hypodiploid sub-G0/G1 cell population. Furthermore, a decreased cdc25C mRNA level was consistently noted in stretched cells. However, the mRNA expressions of Bcl2, Bax, cdc2, and cyclin B1 genes were not significantly altered compared to the unstretched control cells. CONCLUSION: High-level mechanical stretching induced S-phase cell cycle arrest and apoptotic cell death in osteoblastic cells. The results suggest that heavy tensional force is a negative regulator of osteoblastic activities and should, therefore, be minimized if bone formation is attempted during orthodontic/orthopedic treatment.


Assuntos
Osteoblastos/fisiologia , Estresse Fisiológico/fisiologia , Apoptose , Fenômenos Biomecânicos , Proteína Quinase CDC2 , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Ciclina B1/genética , Quinases Ciclina-Dependentes/genética , Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Pontos de Checagem da Fase S do Ciclo Celular , Fosfatases cdc25/genética
16.
J Dent ; 148: 105212, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936456

RESUMO

OBJECTIVES: To investigate the effectiveness of different adjunctive local treatments combined with non-surgical periodontal therapy (NSPT) to reduce pocket depth (PD), gain clinical attachment level (CAL), and/or reduce glycated hemoglobin (HbA1c) in individuals with both type 2 diabetes mellitus (T2DM) and periodontitis in a systematic review and network meta-analysis. DATA SOURCES: Publications were searched in Cochrane databases, EMBASE, Google Scholar, MEDLINE, PubMed, opengrey.eu, and www. CLINICALTRIALS: gov up to May 29, 2024 with no language restriction. STUDY SELECTION: Only randomized controlled trials (RCTs) were included. Network meta-analysis utilized frequentist models. DATA: The network meta-analysis of 30 RCTs involving 1224 patients revealed that, in short-term (2-3 months) and medium-term (4-6 months), adjunctive local treatment involving statins or metformin significantly outperformed scaling and root planning (SRP) with/without additional interventions such as photodynamic and laser therapies (PDT/LT), phytotherapy, doxycycline, bisphosphonates, antibiotics, antiseptics, or placebo for reducing PD and/or gaining CAL. In the long-term (>6 months), statins yielded the most significant additional PD reduction and CAL gain, followed by antibiotics, compared to SRP with antiseptics or placebo. Only PDT/LT demonstrated significantly greater HbA1c reduction in the short term compared to SRP with/without statins, antiseptics, or placebo. CONCLUSION: This study moderately supports that adding metformin or statins locally to NSPT may enhance PD reduction and CAL gain compared to SRP with/without placebo. CLINICAL SIGNIFICANCE: Clinicians are guided to optimize adjunctive therapies, enhancing the health of patients with type 2 diabetes and periodontitis. A strategic approach is proposed to tackle systemic and oral health challenges simultaneously.

17.
Clin Oral Investig ; 17(2): 455-61, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22415218

RESUMO

OBJECTIVES: Transforming growth factor ß (TGFß) has been suggested as the main trigger for the increased collagen production and decreased matrix degradation pathways in oral submucous fibrosis (OSF). Connective tissue growth factor (CTGF/CCN2) and cyclooxygenase-2 (COX-2) were found to overexpress in OSF. The aim of this study was to investigate the molecular mechanism underlying the TGFß-induced CCN2 expressions in human buccal mucosal fibroblasts (BMFs) to identify the potential targets for drug intervention or chemoprevention of OSF. MATERIALS AND METHODS: TGFß-induced CCN2 expression and its signaling pathways were assessed by Western blot analyses in BMFs. RESULTS: TGFß1 stimulated CCN2 synthesis in BMFs. Pretreatment with c-Jun NH(2)-terminal kinase (JNK) inhibitor SP600125, p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580, and activin receptor-like kinase 5 (ALK5) inhibitor SB431542 significantly reduced TGFß1-induced CCN2 synthesis. Epigallocatechin-3-gallate (EGCG) completely blocked TGFß1-induced CCN2 synthesis by inhibiting the phosphorylation of JNK and p38 MAPK. Prostaglandin E(2) (PGE(2)) inhibited the TGFß1-induced CCN2 synthesis in human fetal lung fibroblasts IMR90 but not in BMFs. CONCLUSIONS: The TGFß1-induced CCN2 synthesis in BMFs could be mediated by the ALK5, JNK, and p38 MAPK pathways. EGCG blocks TGFß1-induced CCN2 by suppressing JNK and p38 in BMFs. CLINICAL RELEVANCE: The exceptional signal transduction pathways of TGFß1-induced CCN2 production in BMFs contribute to the resistance of PGE(2) downregulation of CCN2 expression; therefore, the CTGF/CCN2 levels are maintained in the OSF tissues in the presence of COX-2. EGCG may serve as a useful agent in controlling OSF.


Assuntos
Catequina/análogos & derivados , Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Fibroblastos/efeitos dos fármacos , MAP Quinase Quinase 4/antagonistas & inibidores , Mucosa Bucal/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Fator de Crescimento Transformador beta1/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Antracenos/farmacologia , Benzamidas/farmacologia , Catequina/farmacologia , Linhagem Celular , Células Cultivadas , Fator de Crescimento do Tecido Conjuntivo/efeitos dos fármacos , Dinoprostona/farmacologia , Dioxóis/farmacologia , Relação Dose-Resposta a Droga , Fibroblastos/enzimologia , Flavonoides/farmacologia , Humanos , Imidazóis/farmacologia , Pulmão/citologia , Pulmão/efeitos dos fármacos , Mucosa Bucal/citologia , Fibrose Oral Submucosa/enzimologia , Fibrose Oral Submucosa/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores
18.
J Formos Med Assoc ; 112(12): 801-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24331110

RESUMO

This report presents a case of a 12-year-old girl with maxillary deficiency, mandibular prognathism, and facial asymmetry, undergoing growth hormone (GH) therapy due to idiopathic short stature. Children of short stature with or without GH deficiency have a deviating craniofacial morphology with overall smaller dimensions; facial retrognathism, especially mandibular retrognathism; and increased facial convexity. However, a complete opposite craniofacial pattern was presented in our case of a skeletal Class III girl with idiopathic short stature. The orthodontic treatment goal was to inhibit or change the direction of mandibular growth and stimulate the maxillary growth of the girl during a course of GH therapy. Maxillary protraction and mandibular retraction were achieved using occipitomental anchorage (OMA) orthopedic appliance in the first stage of treatment. In the second stage, the patient was treated with a fixed orthodontic appliance using a modified multiple-loop edgewise archwire technique of asymmetric mechanics and an active retainer of vertical chin-cup. The treatment led to an acceptable facial profile and obvious facial asymmetry improvement. Class I dental occlusion and coincident dental midline were also achieved. A 3½-year follow-up of the girl at age 18 showed a stable result of the orthodontic and dentofacial orthopedic treatment. Our case shows that the OMA orthopedic appliance of maxillary protraction combined with mandibular retraction is effective for correcting skeletal Class III malocclusion with midface deficiency and mandibular prognathism in growing children with idiopathic short stature undergoing GH therapy.


Assuntos
Nanismo Hipofisário/tratamento farmacológico , Hormônio do Crescimento/uso terapêutico , Ortodontia Corretiva/métodos , Prognatismo/terapia , Adolescente , Criança , Assimetria Facial/complicações , Feminino , Humanos , Má Oclusão Classe III de Angle
19.
J Formos Med Assoc ; 111(10): 560-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23089691

RESUMO

BACKGROUND/PURPOSE: A smooth enamel surface after the removal of a bracket from a tooth is essential for both esthetic demands and the prevention of plaque accumulation. The purpose of this study was to evaluate enamel damage caused by three standardized debracketing techniques. METHODS: We established three standardized test devices based on the principles of the squeezing, shearing, and tensile testing methods, which were simulated using a How Plier (TASK 60-306), a Direct Bond Bracket Remover (TASK 60-335 T), and a Lift-Off Debracketing Instrument (3 M-Unitek 444-761), respectively. Thirty teeth in each group were evaluated after debracketing. An optical stereomicroscope and a CCD camera with a computerized image analysis system were used to ascertain the proportion of remnant adhesive area (RAE) on the enamel surface. Fractography was analyzed using a scanning electron microscope. RESULTS: The squeezing debracketing method exhibited the highest debonding force (54.3 ± 7.0 N) and the least damage to the enamel surface (RAE = 99.5% ± 2.4%). The tensile debracketing method preserved most of the adhesive on the enamel surface (RAE = 98.7% ± 3.3%) and required the least debonding force (6.8 ± 1.2 N). However, the shearing debracketing method exhibited a significantly higher debonding force (32.0 ± 8.2 N) and smaller RAE (77.3% ± 33.5%) compared to the tensile debracketing method (p < 0.05). Three specimens appeared to have vertical fractures on their enamel prisms when using the shearing method. CONCLUSION: With the proposed method, we conclude that the squeezing and tensile methods are acceptable for clinical use when debracketing, whereas the Direct Bond Bracket Remover may cause shearing failure, leading to a risk for enamel damage.


Assuntos
Descolagem Dentária/efeitos adversos , Descolagem Dentária/métodos , Esmalte Dentário/lesões , Braquetes Ortodônticos , Cimentos Dentários/efeitos adversos , Descolagem Dentária/instrumentação , Humanos , Microscopia Eletrônica de Varredura
20.
Am J Orthod Dentofacial Orthop ; 141(3): 279-288, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22381488

RESUMO

INTRODUCTION: The primary stability of a mini-implant is critical, since most orthodontic mini-implant failures occur at an early stage. As orthodontic mini-implants have restrictions in diameter and length, an optimal design of the shape is important for sufficient primary stability. The purpose of this study was to investigate the influence of various mini-implants design factors, including thread depth, degree of taper, and taper length on insertion torque, pullout strength, stiffness, and screw displacement before failure. METHODS: Finite element analyses were conducted first for identification of optimal design parameters. Four types of mini-implants with different design parameters were then custom manufactured and tested mechanically. All mechanical tests were performed in artificial bone with homogenous density to remove the variability associated with bone. RESULTS: Finite element results showed that, for mini-implants with a fixed external diameter of 2 mm, a thread length of 9.82 mm, and a pitch of 0.75 mm, those with greater thread depths, smaller taper degrees, and shorter taper lengths generated higher maximum stresses on the bone and thread elements. These mini-implants also had larger relative displacements. Maximum pullout resistance was attained with a core/external diameter ratio of 0.68. All mechanical results were compatible with the findings in the finite element analyses. CONCLUSIONS: Modification of the mini-implant design can substantially affect the mechanical properties. The finite element method is an effective tool to identify optimal design parameters and allow for improved mini-implant designs.


Assuntos
Implantes Dentários , Procedimentos de Ancoragem Ortodôntica/instrumentação , Desenho de Aparelho Ortodôntico , Ligas , Fenômenos Biomecânicos , Densidade Óssea/fisiologia , Osso e Ossos/fisiologia , Desenho Assistido por Computador , Ligas Dentárias/química , Análise do Estresse Dentário/instrumentação , Módulo de Elasticidade , Falha de Equipamento , Análise de Elementos Finitos , Humanos , Estresse Mecânico , Propriedades de Superfície , Titânio/química , Torque
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