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1.
Am J Orthod Dentofacial Orthop ; 163(3): 426-442, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36437146

RESUMO

Sotos syndrome is a genetic disorder characterized by overgrowth in childhood, specific facial manifestations, advanced bone age, and mental retardation. The purpose of this article is to describe the nonsurgical orthodontic treatment of a 10-year-old boy with a skeletal mandibular protrusion, unilateral posterior crossbite, and Sotos syndrome. After maxillary lateral expansion, the skeletal Class III relationship with an anterior crossbite improved because of mandibular clockwise rotation, whereas the facemask had a marginal effect. After growth at 16 years, he had a skeletal Class I relationship, and thus, conventional orthodontic treatment with preadjusted edgewise appliances was initiated. After 41 months of multibracket treatment, acceptable occlusion with a functional Class I relationship was obtained. One year postretention, few changes in occlusion and facial features were observed. Our results demonstrate that considering the maxillofacial vertical growth during the peripubertal period associated with Sotos syndrome, more attention should be paid to the early orthopedic treatment with the facemask and/or chincap.


Assuntos
Má Oclusão Classe III de Angle , Má Oclusão , Síndrome de Sotos , Masculino , Humanos , Criança , Má Oclusão Classe III de Angle/terapia , Cefalometria , Mandíbula , Técnica de Expansão Palatina , Aparelhos de Tração Extrabucal , Maxila
2.
J Contemp Dent Pract ; 22(10): 1184-1190, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35197388

RESUMO

AIM AND OBJECTIVE: To present an Apert syndrome patient with midfacial growth deficiency treated with Le Fort III distraction osteogenesis and subsequent two-jaw surgery. BACKGROUND: Apert syndrome is expressed as a severe and irregular craniosynostosis, midfacial hypoplasia, and symmetric syndactyly in the fingers and toes. For craniosynostosis syndromes, treatment planning is complex due to the disharmony between facial profile and occlusion. CASE DESCRIPTION: A 4-year-and-5-month-old boy, diagnosed with Apert syndrome, showed a concave profile accompanied with midfacial hypoplasia, moderate exorbitism, a reversed occlusion of -10.0 mm, an anterior open bite of -5.0 mm, and skeletal class III jaw-base relationship. The patient, aged 15 years and 4 months, underwent a Le Fort III osteotomy, and subsequent osteodistraction was performed via a rigid external distraction (RED) device. His midfacial bone was advanced by approximately 7.0 mm. One year after the distraction, preoperative treatment with 0.018-in preadjusted edgewise appliances was initiated. Two-jaw surgery with a Le Fort I osteotomy and bilateral sagittal split ramus osteotomy was performed after 42 months of preoperative orthodontic treatment. At the age of 20 years and 9 months, his facial profile dramatically changed to a straight profile, and an acceptable occlusion with an adequate interincisal relationship was obtained. A functional occlusion with an excellent facial profile was maintained throughout the 2-year retention period, although the upper dental arch width was slightly decreased, resulting in the recurrence of the left posterior crossbite. CONCLUSION: Our report indicates the necessity of long-term follow-up in patients with craniosynostosis because of syndrome-specific growth and methodologically induced relapse. CLINICAL SIGNIFICANCE: The two-stage operation combining early distraction osteogenesis and postgrowth orthognathic surgery proves to be an effective therapy for correcting midfacial hypoplasia and skeletal mandibular protrusion caused by Apert syndrome.


Assuntos
Acrocefalossindactilia , Mordida Aberta , Osteogênese por Distração , Acrocefalossindactilia/complicações , Acrocefalossindactilia/cirurgia , Adolescente , Adulto , Cefalometria/métodos , Humanos , Lactente , Masculino , Mordida Aberta/etiologia , Osteogênese por Distração/efeitos adversos , Osteogênese por Distração/métodos , Osteotomia de Le Fort/métodos , Adulto Jovem
3.
J Contemp Dent Pract ; 22(6): 713-720, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34393132

RESUMO

AIM: To report a treatment case of mandibular deviation caused by congenital cervical lymphangioma with traditional orthodontic techniques, following-up by 10-year retention. BACKGROUND: Lymphangiomas, developmental anomalies, can induce various disturbances of swallowing, mastication, speech, breathing, and skeletal deformities as well as psychological stress and anxiety for the patient and their family. Lymphangiomas are benign with virtually no possibility of turning into a malignant lesion, so clinical management aims to treat the patient functionally. CASE DESCRIPTION: A girl, aged 6 years and 4 months, complained about facial asymmetry and anterior crossbite caused by congenital cervical lymphangioma. Her facial profile was the straight type with an adequate lip position. Anterior and right-side posterior crossbites were observed. On the frontal cephalogram, the menton shifted 3.0 mm to the right. A functional appliance with an expander was placed to correct her dental midline deviation and posterior crossbite. After 2-year treatment, the anterior and right-side posterior crossbites were improved. Multibracket treatment began after the growth spurt. After 44-month active treatment, a functional occlusion, including a Class I molar relationship with a proper interincisal relationship, was achieved. A functional occlusion was maintained during a 10-year retention period, while a mandibular downward growth was observed through the retention period. CONCLUSION: Conventional orthodontic techniques enable functional and stable occlusion even in patients with mandibular deviation caused by congenital cervical lymphangioma, although only using early orthodontic management by itself may have some limitations. CLINICAL SIGNIFICANCE: The hybrid technique combining functional appliance and intermaxillary elastics proves to be an effective therapy for correcting occlusal cant and mandibular deviation caused by cervical lymphangioma.


Assuntos
Linfangioma , Má Oclusão , Cefalometria , Assimetria Facial , Feminino , Seguimentos , Humanos , Linfangioma/complicações , Linfangioma/terapia , Mandíbula
4.
Genes Dev ; 25(18): 1982-96, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21937715

RESUMO

Members of the Flamingo cadherin family are required in a number of different in vivo contexts of neural development. Even so, molecular identities downstream from the family have been poorly understood. Here we show that a LIM domain protein, Espinas (Esn), binds to an intracellular juxtamembrane domain of Flamingo (Fmi), and that this Fmi-Esn interplay elicits repulsion between dendritic branches of Drosophila sensory neurons. In wild-type larvae, branches of the same class IV dendritic arborization neuron achieve efficient coverage of its two-dimensional receptive field with minimum overlap with each other. However, this self-avoidance was disrupted in a fmi hypomorphic mutant, in an esn knockout homozygote, and in the fmi/esn trans-heterozygote. A functional fusion protein, Fmi:3eGFP, was localized at most of the branch tips, and in a heterologous system, assembly of Esn at cell contact sites required its LIM domain and Fmi. We further show that genes controlling epithelial planar cell polarity (PCP), such as Van Gogh (Vang) and RhoA, are also necessary for the self-avoidance, and that fmi genetically interacts with these loci. On the basis of these and other results, we propose that the Fmi-Esn complex, together with the PCP regulators and the Tricornered (Trc) signaling pathway, executes the repulsive interaction between isoneuronal dendritic branches.


Assuntos
Caderinas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriologia , Drosophila melanogaster/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Dendritos/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Inativação de Genes , Proteínas do Tecido Nervoso/genética , Sistema Nervoso/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Células Receptoras Sensoriais/citologia , Células Receptoras Sensoriais/metabolismo
5.
Am J Dent ; 31(2): 67-70, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29630788

RESUMO

PURPOSE: To evaluate the effect of pulsed ultrasound toothbrush on the removal of biofilm formed by Streptococcus mutans (S. mutans). METHODS: S. mutans biofilm grown on apatite pellet was destructed with four different sonic action toothbrushes: 1) pulsed ultrasound with sonic vibration (PUV); 2) continuous ultrasound with sonic vibration (CUV); 3) sonic vibration only (SV); and 4) no ultrasound nor sonic vibration (control). After 3 minutes of noncontact brushing, the amount of water-insoluble glucan was measured, and the residual biofilm was observed by scanning electron microscopy. RESULTS: PUV group revealed the smallest amount of the residual water-insoluble glucans (32 ± 19%), followed by the CUV group (54 ± 12%) and the SV group (64 ± 13%). The PUV group showed a significantly lower amount of the residual water-insoluble glucan than the SV group, while no significant difference was found between SV and CUV. The bacterial adherence and aggregation notably decreased in the PUV group, compared to the remaining three groups. CLINICAL SIGNIFICANCE: The sonic vibration with pulsed ultrasound showed more reduction of the biofilm compared to the control and the sonic vibration with and without continuous ultrasound. Thus, pulsed ultrasound action may be beneficial for biofilm removal of interproximal regions.


Assuntos
Placa Dentária , Streptococcus mutans , Escovação Dentária , Ondas Ultrassônicas , Biofilmes , Humanos , Escovação Dentária/instrumentação
6.
Am J Orthod Dentofacial Orthop ; 151(4): 793-803, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28364903

RESUMO

We successfully treated a patient with achondroplasia with conventional orthodontic techniques. It was followed by long-term retention. The patient, a 12-year-old boy, had chief complaints of occlusal disturbance and mandibular protrusion. He had been diagnosed with achondroplasia and had growth hormone treatment in his early teenage years. His facial profile was concave with a bulging forehead and a retrognathic maxilla. It was characterized by a skeletal Class III jaw-base relationship with a retropositioned maxilla. At the age of 12 years 9 months, maxillary protraction was initiated with a reverse headgear; for 2 years 6 months, the maxillomandibular growth was controlled. After the growth spurt, at the age of 15 years 6 months, leveling and alignment of both dental arches were started with preadjusted edgewise appliances. After 83 months of multibracket treatment, an acceptable occlusion with a Class I molar relationship and an adequate interincisal relationship was achieved, despite the simultaneous marked vertical growth of the mandible. The resultant occlusion was stable during a 6-year retention period, although considerable forward-downward mandibular growth was observed. Conclusively, our results indicated the necessity of long-term observation in this patient with achondroplasia, especially because of the persistent mandibular growth.


Assuntos
Acondroplasia/terapia , Má Oclusão Classe III de Angle/terapia , Ortodontia Corretiva/métodos , Acondroplasia/patologia , Assistência ao Convalescente , Criança , Seguimentos , Humanos , Masculino , Má Oclusão Classe III de Angle/patologia
7.
Dev Dyn ; 243(6): 791-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24403181

RESUMO

BACKGROUND: Planar cell polarity (PCP) originally referred to the coordination of global organ axes and individual cell polarity within the plane of the epithelium. More recently, it has been accepted that pertinent PCP regulators play essential roles not only in epithelial sheets, but also in various rearranging cells. RESULTS: We identified pepsinogen-like (pcl) as a new planar polarity gene, using Drosophila wing epidermis as a model. Pcl protein is predicted to belong to a family of aspartic proteases. When pcl mutant clones were observed in pupal wings, PCP was disturbed in both mutant and wild-type cells that were juxtaposed to the clone border. We examined levels of known PCP proteins in wing imaginal discs. The amount of the seven-pass transmembrane cadherin Flamingo (Fmi), one of the PCP "core group" members, was significantly decreased in mutant clones, whereas neither the amount of nor the polarized localization of Dachsous (Ds) at cell boundaries was affected. In addition to the PCP phenotype, the pcl mutation caused loss of wing margins. Intriguingly, this was most likely due to a dramatic decrease in the level of Wingless (Wg) protein, but not due to a decrease in the level of wg transcripts. CONCLUSIONS: Our results raise the possibility that Pcl regulates Wg expression post-transcriptionally, and PCP, by proteolytic cleavages.


Assuntos
Caderinas/metabolismo , Proteínas de Drosophila/biossíntese , Proteínas de Drosophila/metabolismo , Embrião não Mamífero/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Discos Imaginais/embriologia , Proteólise , Proteína Wnt1/biossíntese , Animais , Drosophila melanogaster , Embrião não Mamífero/citologia , Discos Imaginais/citologia
8.
Implant Dent ; 23(5): 576-81, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25192157

RESUMO

OBJECTIVE: To evaluate the torque ratio (TR) as a predictable factor on primary stability of orthodontic miniscrews. DESIGN: Fifty-eight orthodontic patients (17 men, 41 women; mean age, 21.9 years) with a total of 112 titanium miniscrews of 3 different diameters were subjected. Maximum insertion torque (MIT) and maximum removal torque (MRT) were measured by a digital torque checker at the screw placement. Four weeks after the placement, the stable screw was recorded as a success. Multiple logistic regression analysis was performed to estimate the influence of each clinical variable on success. RESULTS: Success rates were 82.1% to 89.5%, and there were no significant differences in the 3 types of miniscrews. MIT and MRT showed a positive correlation but did not affect the success rates of miniscrews directly. On the contrary, TR was significantly higher in the success group than in the failure group. In multiple regression analysis, age, TR, and screw proximity had a significant influence on the miniscrew success. CONCLUSIONS: TR might be related with the miniscrew success rates, and it can be used as a predictable factor on primary stability of orthodontic miniscrew implants. Miniscrew implants should be replaced if MRT is significantly lower than MIT at placement surgery.


Assuntos
Parafusos Ósseos , Ortodontia , Torque
9.
Genes Cells ; 17(6): 509-24, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22563761

RESUMO

Planar cell polarity (PCP) refers to the coordination of global organ axes and individual cell polarity in vertebrate and invertebrate epithelia. Mechanisms of PCP have been best studied in the Drosophila wing, in which each epidermal cell produces a single wing hair at the distal cell edge, and this spatial specification is mediated by redistribution of the core group proteins, including the seven-pass transmembrane cadherin Flamingo/Starry night (Fmi/Stan), to selective plasma membrane domains. Through genetic screening, we found that a mutation of the SMC3 gene caused dramatic misspecification of wing hair positions. SMC3 protein is one subunit of the cohesin complex, which regulates sister chromatid cohesion and also plays a role in transcriptional control of gene expression. In the SMC3 mutant cells, Fmi appeared to be upregulated by a posttranscriptional mechanism(s), and this elevation of Fmi was at least one cause of the PCP defect. In addition to the PCP phenotype, the loss of the cohesin function affected wing morphogenesis at multiple levels: one malformation was loss of the wing margin, and this was most likely a result of downregulation of the homeodomain protein Cut. At the cellular level, apical cell size and hexagonal packing were affected in the mutant wing. Dysfunction of cohesin in humans results in Cornelia de Lange syndrome (CdLS), which is characterized by various developmental abnormalities and mental retardation. Our analysis of cohesin in epithelia may provide new insight into cellular and molecular mechanisms of CdLS.


Assuntos
Adenosina Trifosfatases/metabolismo , Caderinas/metabolismo , Polaridade Celular , Proteínas de Drosophila/metabolismo , Drosophila/citologia , Drosophila/metabolismo , Adenosina Trifosfatases/genética , Animais , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Drosophila/genética , Embrião não Mamífero/metabolismo , Proteínas de Homeodomínio/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Asas de Animais/citologia , Asas de Animais/embriologia , Coesinas
10.
Case Rep Dent ; 2022: 5209667, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35284144

RESUMO

In the case of multiple facial fractures, a simple open reduction occasionally causes various disorders during healing process after the surgery. Moreover, esthetic disturbance of a facial deformity might be induced. Therefore, the acquisition of facial symmetry and the recovery of occlusal and masticatory functions become increasingly important. This case report presents a successful treatment of facial multiple fracture induced by a car accident. A 20-year-old male was diagnosed with suffered multiple midface and mandibular fractures induced by a car accident. Midface fractures included the LeFort I and II type fractures, as well as sagittal fracture at midline and fractures from right maxillary sinus anterior wall to orbital wall. In the mandible, midline and left body fractures were detected. The patient underwent open reduction and rigid fixation of the fractured left zygoma, comminuted LeFort I and II fractures, and midline and left body of the mandible with intermaxillary fixation by multibracket appliance; maxillary osteotomy with iliac bone grafting; orthognathic two-jaw surgery with coronoid process grafts onto the depressed zygoma; and onlay graft of hydroxyapatite block on mandible. As the result, the multidisciplinary treatments successfully recover functions and esthetics to the satisfactory level of the patient with multiple facial fractures. As treatments for multiple facial fractures are required complexity due to the extent of trauma, multidisciplinary approach under the close cooperation between hospital departments is thought to be important.

11.
J Dent Sci ; 17(3): 1217-1224, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35784158

RESUMO

Background/purpose: Patients with jaw deformities may show a reduction in masticatory function as a result of postoperative hypofunction. This study aimed to establish a novel rehabilitation program using a commercially available masticatory training food for patients with jaw deformities after orthognathic surgery. Materials and methods: Nine patients with mandibular prognathism (the training group: n = 5, and the non-training group: n = 4) and 6 control participants with normal occlusion were included in this study. For the rehabilitation program with masticatory exercise, patients were instructed to chew the training food once a day for 60 days starting from 10 days after the surgery. The effects of the rehabilitation program were assessed by determining the maximum bite force (MBF) and the masticatory performance (MP). Clinical assessments were performed just before orthognathic surgery (Pre) and at 10 days (T0), 1 month (T1), 2 months (T2), and 3 months (T3) after surgery. Results: Compared with the non-training group, the training group showed a trend toward greater recovery amount of MBF from Pre to T3, and a significantly greater recovery amount in MP (p < 0.05) from Pre to T3. When the time-series change of MP was evaluated in both groups from T0 to T3, a significant difference was observed in the interaction terms (p = 0.03). This result indicates that the effectiveness of the training may be demonstrated by following the postoperative course further. Conclusion: The rehabilitation using this training food may become a useful method for postoperative hypofunction in patients with jaw deformities.

12.
J Dent Sci ; 17(2): 822-830, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35756806

RESUMO

Background/purpose: Surgical orthodontic treatment is recommended for patients with severe dentoskeletal discrepancies, while camouflage orthodontic treatment is recommended for patients with mild to moderate discrepancies. However, the decision as to which treatment should be chosen is complicated. The purpose of this study was to determine differences in masticatory function in patients who underwent camouflage and surgical orthodontic treatment for skeletal Class III malocclusion, as well as the usefulness of Wits appraisal in treatment decision based on masticatory functional analysis. Materials and methods: The study subjects were 45 patients with skeletal Class III malocclusion (15 cases with camouflage orthodontics and 30 cases with orthognatic surgery) and 12 individuals with normal occlusion. We analyzed the pre-treatment records of electromyographic activities of masseter and temporalis muscles and jaw movements. Results: There were no significant differences in various functional measurements between the camouflage and surgery groups. However, there were significant but not strong correlations between ANB and both masseter muscle activity (r = 0.36, p < 0.01) and expression ratio of abnormal chewing (r = -0.54, p < 0.01). Division of patients into two groups using a cutoff value of -6.0 mm for Wits appraisal showed a significant difference in masseter muscle activity between -6.0 mm or less group and the control (p < 0.01) but none between more than -6.0 mm group and the control. Conclusion: Camouflage orthodontic treatment is inappropriate for patients with relatively severe dentoskeletal discrepancies. Wits appraisal of -6.0 mm is a potentially useful parameter for treatment decision.

13.
Sci Rep ; 12(1): 12367, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35859046

RESUMO

Cortical bone thickness is assumed to be a major factor regulating miniscrew stability. We investigated stress distribution in two miniscrews with different thread shapes (type A and B) and in cortical bone of three different thicknesses using three-dimensional (3D) finite element (FE) models. More specifically, 3D FE models of two different miniscrews were created and placed obliquely or vertically into a cylindrical bone model representing different cortical bone thicknesses. When force was applied to the miniscrew, the stress distribution on the screw surface and in the peri-implant bone was assessed using FE methodology. Miniscrew safety was evaluated using a modified Soderberg safety factor. Screw head displacement increased with a decrease in cortical bone thickness, irrespective of screw type. The smallest minimum principal stresses on the screw surfaces remained constant in type A miniscrews on changes in cortical bone thickness. Minimum principal stresses also appeared on the cortical bone surface. Lower absolute values of minimum principal stresses were seen in type A miniscrews when placed vertically and with upward traction in obliquely placed type B miniscrews. Both miniscrews had acceptable safety factor values. Taken together, orthodontists should select and use the suitable miniscrew for each patient in consideration of bone properties.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Osso Cortical , Análise de Elementos Finitos , Humanos , Procedimentos de Ancoragem Ortodôntica/métodos , Desenho de Aparelho Ortodôntico , Estresse Mecânico , Titânio
14.
Dent Mater J ; 41(3): 487-494, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35264547

RESUMO

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.


Assuntos
Colagem Dentária , Cimentos de Ionômeros de Vidro , Resinas Compostas/química , Materiais Dentários/química , Análise do Estresse Dentário , Condutividade Elétrica , Cimentos de Ionômeros de Vidro/química , Imersão , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Cloreto de Sódio , Propriedades de Superfície
15.
Dent Mater J ; 40(1): 35-43, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32779608

RESUMO

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 effect 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.


Assuntos
Colagem Dentária , Líquidos Iônicos , Resinas Compostas , Análise do Estresse Dentário , Cimentos de Ionômeros de Vidro , Imersão , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Água
16.
Dent Mater J ; 29(2): 193-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20379030

RESUMO

The purpose of this study was to examine the antibacterial activity of composite resin with glass-ionomer filler particles versus that of contemporary commercial composite resins. Three composite resins were used: Beautifil II (containing S-PRG filler), Clearfil AP-X, and Filtek Z250. Resin blocks were bonded to maxillary first molars, and plaque accumulation on the resin block surface was examined after 8 hours. For the antibacterial test, the number of Streptococcus mutans in contact with the composite resin blocks after incubation for 12 hours was determined, and adherence of radiolabeled bacteria was evaluated. Less dental plaque was formed on Beautifil II resin block as compared to the other two materials. Antibacterial test revealed that there were no significant differences in the number of Streptococcus mutans among the three composite resins. However, the adherence of radiolabeled bacteria to the saliva-treated resin surface was significantly (p<0.01) lower in Beautifil II than in the other two materials. These results suggested that Beautifil II could reduce dental plaque formation and bacterial adherence, leading to prevention of secondary caries.


Assuntos
Antibacterianos/farmacologia , Resinas Compostas/farmacologia , Materiais Dentários/farmacologia , Cimentos de Ionômeros de Vidro/farmacologia , Adulto , Aderência Bacteriana , Compostos de Bário/química , Compostos de Bário/farmacologia , Bis-Fenol A-Glicidil Metacrilato/química , Bis-Fenol A-Glicidil Metacrilato/farmacologia , Contagem de Colônia Microbiana , Resinas Compostas/química , Materiais Dentários/química , Placa Dentária/microbiologia , Feminino , Vidro/química , Cimentos de Ionômeros de Vidro/química , Humanos , Masculino , Teste de Materiais , Metacrilatos/química , Metacrilatos/farmacologia , Cimentos de Resina/química , Cimentos de Resina/farmacologia , Saliva/fisiologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Método Simples-Cego , Espectrometria por Raios X , Streptococcus mutans/crescimento & desenvolvimento , Propriedades de Superfície , Fatores de Tempo , Zircônio/química , Zircônio/farmacologia
17.
J Dent Sci ; 15(4): 419-425, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33505611

RESUMO

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 < 0.01; EI: p < 0.01), indicating the improvement of activity balance of masseter and temporalis muscles and conversion of the jaw movement from abnormal to normal pattern (p < 0.01). CONCLUSION: Our findings suggested that functional training using the gum chewing and patient-education exercise improved masticatory function in patients with mandibular prognathism.

18.
Biomed Mater Eng ; 19(2-3): 121-31, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19581705

RESUMO

Synthetic bone cement that has zinc oxide core particles covered with hydroxyapatite (HAP) was developed; that is, the conversion of hopeite, the traditional zinc phosphate cement, into HAP was attempted. Here, hopeite is the final product of the reaction between powders and trituration liquid of the traditional zinc phosphate cement. This cement may have many advantages not only in terms of biological functions but also the setting process of the traditional cement and the mechanical properties of the developed compact if the hopeite can be converted into calcium phosphate (CP). In this study, calcium nitrate solutions of various concentrations were used for the conversion of hopeite crystals into CP. The products after the solution treatment were analyzed by X-ray diffractometry (XRD), Fourier transform infrared spectrometry (FTIR), and scanning electron microscope (SEM) observation. These results indicated that the converted scholzite crystals could be partially detected. Several types of set zinc phosphate cement with different P/L ratios were arranged. The surface products of the set cement after the solution treatment were analyzed by XRD. However, the crystal phase such as hopeite was not detected except for zinc oxide. The set cement, which was treated with the calcium nitrate solution, was immersed in simulated body fluid (SBF). HAP-like crystals on the set cement could be detected for the specimens immersed for 4 weeks. These findings suggested that the binding phase in the set cement could be converted into HAP by immersion in SBF.


Assuntos
Materiais Biocompatíveis/química , Líquidos Corporais/química , Cimentos Ósseos/química , Durapatita/química , Fosfatos/química , Compostos de Zinco/química , Absorção , Adesividade , Cristalização/métodos , Dureza , Teste de Materiais , Tamanho da Partícula , Porosidade , Propriedades de Superfície
19.
Angle Orthod ; 88(5): 602-610, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29799272

RESUMO

OBJECTIVES: To determine the frictional force (FF) of the novel, elastic, bendable titanium-niobium (Ti-Nb) alloy orthodontic wire in stainless steel (SS) brackets and to compare it with those of titanium-nickel (Ti-Ni) and titanium-molybdenum (Ti-Mo) alloy wires. MATERIALS AND METHODS: Three sizes of Ti-Nb, Ti-Ni, and Ti-Mo alloy wires were ligated with elastic modules to 0.018-inch and 0.022-inch SS brackets. The dynamic FFs between the orthodontic wires and SS brackets were measured at three bracket-wire angles (0°, 5°, and 10°) with an Instron 5567 loading apparatus (Canton, Mass). RESULTS: FFs increased gradually with the angle and wire size. In the 0.018-inch-slot bracket, the dynamic FFs of Ti-Nb and Ti-Ni alloy wires were almost the same, and those of the Ti-Mo alloy wire were significantly greater ( P<0.05). FF values were 1.5-2 times greater in the 0.022-inch-slot bracket than in the 0.018-inch-slot bracket, regardless of alloy wire type, and the Ti-Mo alloy wire showed the greatest FF. Scanning electric microscopic images showed that the surface of the Ti-Mo alloy wire was much rougher than that of the Ti-Ni and Ti-Nb alloy wires. CONCLUSION: These findings demonstrate that the Ti-Nb alloy wire has almost the same frictional resistance as the Ti-Ni alloy wire, although it has a higher elastic modulus.


Assuntos
Fios Ortodônticos , Ligas , Elasticidade , Fricção , Técnicas In Vitro , Aço Inoxidável
20.
Saudi Med J ; 39(2): 169-178, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29436566

RESUMO

OBJECTIVES: To evaluate the effectiveness of pre-surgical nasoalveolar molding (PNAM) in patients with unilateral cleft lip nasal deformities. Methods: This was a retrospective study involving 29 patients with unilateral cleft lip and palate defects, of whom 13 were treated with palatal devices with nasal stents (PNAM group) and 16 were treated with palatal devices without nasal stents or surgical tapes (control group). Submental oblique photographs and orthodontic models were longitudinally obtained at the initial visit (T1) and immediately before (T2) and  after cheiloplasty (T3). Asymmetry of the external nose, degree of columellar shifting, nasal tip/ala nose ratio, nasal base angle, interalveolar gap, and the sagittal difference in the alveolar gap were measured. The study was conducted in the Orthodontic Clinic at Tokushima University Hospital, Tokushima, Japan between 1997 and 2012. Results: At T1, there were no significant intergroup differences in the first 4 asymmetry parameters. At T2, the PNAM group showed a significant improvement in all values compared to the control group. At T3, the PNAM group showed significant improvement in nasal asymmetry and columellar shifting. Model analysis showed significantly greater changes in the inter-alveolar gap and the sagittal difference of the alveolar cleft gap from T1 to T2 in the PNAM group. Conclusion: The use of PNAM is indispensable for pre-surgical orthodontic treatment at the early postnatal age.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Nariz/anormalidades , Cuidados Pré-Operatórios , Stents , Pontos de Referência Anatômicos , Humanos , Lactente , Recém-Nascido , Nariz/patologia , Fotografação , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos
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