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1.
J Esthet Restor Dent ; 32(7): 638-644, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32603555

RESUMO

OBJECTIVE: Restorative treatment of anterior teeth is often required as the final step of orthodontic therapy to optimize the esthetics and function. This case report presents a direct minimally invasive approach for post-orthodontic recontouring of anterior teeth using the composite injection technique with a digital workflow. CLINICAL CONSIDERATIONS: The extraction of central incisors with short roots was indicated to resolve maxillary anterior crowding. The gained space was closed with lateral incisors, and it was necessary to recontour them and canines to resemble central and lateral incisors, respectively. The restorations were digitally designed, and a transparent silicone index was fabricated from a 3D-printed cast of the digital wax-up. After lateral incisors and canines were bonded with a universal adhesive in the etch-and-rinse mode, a highly filled injectable composite resin was applied into the index. The restorative treatment was preceded by gingivectomy using an Er:YAG laser and home bleaching. CONCLUSIONS: In cases where more complex recontouring of anterior teeth is necessary, the composite injection technique could be a suitable alternative to indirect restorations, because it is straightforward, cost-effective, and does not require any preparation. The digital workflow simplified and expedited the treatment while contributing to its precision. CLINICAL SIGNIFICANCE: Post-orthodontic recontouring using direct composite restorations is well accepted by patients due to low cost and non-invasiveness. However, in complicated cases, the free-hand technique is time-consuming and technique-sensitive. The presented composite injection technique with a digital workflow significantly simplifies and expedites the composite placement while predictably enhancing the treatment outcome.


Assuntos
Restauração Dentária Permanente , Fluxo de Trabalho , Resinas Compostas , Estética Dentária , Humanos , Incisivo
2.
Dent Mater J ; 38(4): 638-645, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31178545

RESUMO

Differences in the volumes of artifacts caused by variously shaped titanium objects on magnetic resonance imaging (MRI) were evaluated. Spherical-, square cubic-, and regular tetrahedron-shaped isotropic, and elongated spherical-, elongated cubic-, and elongated tetrahedron-shaped anisotropic objects, with identical volumes, were prepared. Samples were placed on a nickel-doped agarose gel phantom and covered with nickel-nitrate hexahydrate solution. Three-Tesla MR images were obtained using turbo spin echo and gradient echo sequences. Areas with ±30% of the signal intensity of the standard background value were considered artifacts. Sample volumes were deducted from these volumes to calculate the total artifact volumes. Isotropic samples had similar artifact volumes. For anisotropic samples, the artifact volume increased in proportion with the normalized projection area. MRI artifact size can be reduced by high anisotropic designs, and by positioning the long axis of the metal device as parallel as possible to the magnetic field axis.


Assuntos
Artefatos , Imageamento por Ressonância Magnética , Titânio
3.
Dent Mater J ; 38(1): 22-27, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30158348

RESUMO

The aim of this study was to evaluate in vitro detection of enamel white spot lesions around orthodontic brackets using swept-source optical coherence tomography (SS-OCT). Twenty-four clear orthodontic brackets were bonded onto the enamel surface of bovine incisor specimens using three types of orthodontic resin adhesives: non-fluoridated, fluoridated, and fluoridated light cured. The specimens were subjected to artificial demineralization. SS-OCT images were captured before demineralization and at 24 h and 1 week after demineralization. Lesion depth (LD) was measured and analyzed using Image J software. Results revealed significant increases in LD with time in all three groups. LDs were, however, significantly smaller in the fluoridated adhesive groups than in the non-fluoridated group. In addition, SS-OCT was validated for the detection of micro-leakage and white spot lesions beneath and around the orthodontic brackets.


Assuntos
Braquetes Ortodônticos/efeitos adversos , Tomografia de Coerência Óptica , Desmineralização do Dente/diagnóstico por imagem , Desmineralização do Dente/etiologia , Animais , Bovinos , Cimentos Dentários/química , Fluoretos/química , Processamento de Imagem Assistida por Computador , Técnicas In Vitro , Incisivo , Software
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 1797-1800, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30440743

RESUMO

The purpose of this study is to develop the sensing device which measures three-axis force and three-axis moment for reducing the number of accident in orthodontic treatment. The device is necessary for adequate quantitative evaluation of orthodontic forces during orthodontics. The developed sensing device is composed of six-axis force sensors, tooth models, and arms for connecting sensors and tooth models. The developed device simulates rows of teeth in orthodontic operation and measures $14 \times 6$ axes force and moment from tooth models simultaneously. The averages of the difference of force and moment to theoretical values in each direction are 1.78 % (0.043 N) and 2.72 % (0.60 Nmm) respectively. The average moment applying couple forces is 17.1 % (0.81 Nmm). Then the device is able to measure more accurately as the value of the moment was larger. Therefore using our proposed device, we can conduct the orthodontic treatment which dentition moves large for attaching the rail of wire to the teeth.


Assuntos
Dente , Acidentes , Fenômenos Biomecânicos , Modelos Dentários , Desenho de Aparelho Ortodôntico , Fios Ortodônticos , Estresse Mecânico
5.
J Formos Med Assoc ; 117(1): 71-79, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28408197

RESUMO

BACKGROUND/PURPOSE: The application of an appropriate force system is indispensable for successful orthodontic treatments. Second-order moment control is especially important in many clinical situations, so we developed a new force system composed of a straight orthodontic wire and two crimpable hooks of different lengths to produce the second-order moment. The objective of this study was to evaluate this new force system and determine an optimum condition that could be used in clinics. METHODS: We built a premolar extraction model with two teeth according to the concept of a modified orthodontic simulator. This system was activated by applying contractile force from two hooks that generated second-order moment and force. The experimental device incorporated two sensors, and forces and moments were measured along six axes. We changed the contractile force and hook length to elucidate their effects. Three types of commercial wires were tested. RESULTS: The second-order moment was greater on the longer hook side of the model. Vertical force balanced the difference in moments between the two teeth. Greater contractile force generated a greater second-order moment, which reached a limit of 150 g. Excessive contractile force induced more undesired reactions in the other direction. Longer hooks induced greater moment generation, reaching their limit at 10 mm in length. CONCLUSION: The system acted similar to an off-center V-bend and can be applied in clinical practice as an unconventional loop design. We suggest that this force system has the potential for second-order moment control in clinical applications.


Assuntos
Braquetes Ortodônticos , Fechamento de Espaço Ortodôntico/métodos , Fios Ortodônticos , Técnicas de Movimentação Dentária/instrumentação , Dente Pré-Molar/cirurgia , Fenômenos Biomecânicos , Análise do Estresse Dentário , Humanos , Estresse Mecânico
6.
Am J Orthod Dentofacial Orthop ; 153(1): 54-60, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29287652

RESUMO

INTRODUCTION: Few studies have examined the secondary insertion of orthodontic miniscrews after failure of the first insertion. We investigated both the primary and secondary success rates of miniscrews used for maxillary anchorage and compared the stability of the maxillary buccal area (MB) and the midpalatal suture area (MP). METHODS: In total, 387 miniscrews were primarily inserted into the MB (between the second premolar and first molar); of these, 81 (20.9%) miniscrews lacked stability and were reinserted into the MB (same position or more distal position) or the MP. Additionally, 84 miniscrews were primarily inserted into the MP; 13 (15.5%) of those lacked stability and were reinserted into the MP. We calculated and compared the primary and secondary success rates in each area. Moreover, we investigated the factors affecting clinical success. RESULTS: Although the success rate of the secondary insertion was significantly lower than that of the primary insertion into the MB, miniscrews inserted into the MP were stable in both primary and secondary insertions. The screw length was significantly associated with the stability of miniscrews inserted into the MB. CONCLUSIONS: For secondary insertions, miniscrews placed in the MP may be more stable than those inserted in the MB.


Assuntos
Procedimentos de Ancoragem Ortodôntica/instrumentação , Âncoras de Sutura , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino , Maxila , Palato , Estudos Retrospectivos , Fatores de Risco , Falha de Tratamento , Adulto Jovem
7.
Am J Orthod Dentofacial Orthop ; 152(2): 224-231, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28760284

RESUMO

INTRODUCTION: Although the success of using orthodontic miniscrews for primary insertion has been reported in the literature, few studies have followed up on secondary insertions after failure of the first insertion. In this study, we investigated not only the primary but also secondary success rates of miniscrews and considered the risk factors influencing their stability. METHODS: Five hundred miniscrews were inserted for orthodontic anchorage in 240 patients. Ninety-eight miniscrews lacked stability; thus, 77 of these were removed and reinserted. We calculated and compared the primary and secondary success rates of insertion. Moreover, we investigated which clinical parameters affected the stability of miniscrews. RESULTS: The success rate of secondary insertion (44.2%) was significantly lower than that of primary insertion (80.4%). The screw length and jaw receiving the insertion were significantly associated with the stability of miniscrews. The 8.0-mm miniscrews were significantly more stable than the 6.0-mm miniscrews, and the success rate for insertions into the maxilla was significantly higher than that for the mandible. CONCLUSIONS: Secondary insertions lack stability; therefore, clinicians should be aware of the reduced success rate of reinsertion and know the risk factors to avoid failure of secondary insertions.


Assuntos
Parafusos Ósseos , Procedimentos de Ancoragem Ortodôntica/instrumentação , Adulto , Parafusos Ósseos/efeitos adversos , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Procedimentos de Ancoragem Ortodôntica/métodos , Desenho de Aparelho Ortodôntico , Prognóstico , Resultado do Tratamento , Adulto Jovem
8.
Dent Mater J ; 35(6): 908-917, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27680034

RESUMO

We developed a device to evaluate the orthodontic force applied by systems requiring high operability. A life-sized, two-tooth model was designed, and the measurements were performed using a custom-made jointed attachment, referred to as an "action stick", to allow clearance for the oversized six-axis sensors. This tooth-sensor apparatus was accurately calibrated, and the error was limited. Vector analysis and rotating coordinate transformation were required to derive the force and moment at the tooth from the sensor readings. The device was then used to obtain measurements of the force and moment generated by the V-bend system. Our device was effective, providing results that were consistent with those of previous studies. This measurement device can be manufactured with force sensors of any size, and it can also be expanded to models with any number of teeth.


Assuntos
Modelos Dentários , Técnicas de Movimentação Dentária , Fenômenos Biomecânicos , Fios Ortodônticos , Dente
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 2206-2209, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28268769

RESUMO

The purpose of this study is to develop a sensing system device that measures three-axis orthodontic forces and three-axis orthodontic moments for dentist training. The developed sensing system is composed of six-axis force sensors, action sticks, sliders, and tooth models. The developed system also simulates various types of tooth row shape patterns in orthodontic operations, and measures a 14 × 6 axis orthodontic force and moment from tooth models simultaneously. The average force and moment error per loaded axis were 2.06 % and 2.00 %, respectively.


Assuntos
Modelos Dentários , Modelos Biológicos , Ortodontia/educação , Fenômenos Biomecânicos , Odontólogos , Humanos , Dente/fisiologia
10.
Am J Orthod Dentofacial Orthop ; 148(6): 982-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26672704

RESUMO

INTRODUCTION: Autotransplantation has become a major therapeutic option for replacing missing teeth in adult orthodontic patients. However, little systematic information is available about the long-term stability of autotransplanted teeth with complete root formation after the application of an orthodontic force. The objective of this study was to investigate the outcomes of autotransplanted teeth with complete root formation that underwent orthodontic treatment. METHODS: One hundred teeth, autotransplanted in 89 patients, were examined over a mean observation period of 5.8 years. Orthodontic force was applied with nickel-titanium wires 4 to 8 weeks after autotransplantation. Root resorption, ankylosis, mobility, pocket depth, and inflammation at the recipient site were investigated clinically and with radiographs. RESULTS: The survival rate of the autotransplanted teeth was 93.0%. Abnormal findings were found in 29 teeth, including 7 lost teeth, for a success rate of 71.0%. Donor tooth type and occlusal condition of the donor tooth before transplantation were associated with abnormal findings. CONCLUSIONS: The early application of orthodontic force may increase the success rate of autotransplanted teeth, and the type and presurgical occlusal condition of donor teeth affect the success rate.


Assuntos
Autoenxertos/transplante , Odontogênese/fisiologia , Ortodontia Corretiva , Raiz Dentária/crescimento & desenvolvimento , Dente/transplante , Adolescente , Adulto , Criança , Ligas Dentárias/química , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Níquel/química , Fios Ortodônticos , Bolsa Periodontal/etiologia , Periodontite/etiologia , Estudos Retrospectivos , Reabsorção da Raiz/etiologia , Titânio/química , Anquilose Dental/etiologia , Mobilidade Dentária/etiologia , Resultado do Tratamento , Adulto Jovem
11.
Dent Mater J ; 34(6): 814-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26632229

RESUMO

Although the accumulation and distribution of metals from metallic orthodontic appliances in the oral mucosa have been studied extensively, they remain unclear because their concentration is quite low. In this study, metal specimens (Ni, Ni-Ti, and Co-Cr) were sutured in the unilateral oral mucosa of rats, and the distribution of the eluted elements in the mucosal tissue was estimated using inductively coupled plasma mass spectrometry (ICP-MS) and synchrotron radiation X-ray fluorescence analysis (SR-XRF). While the infiltrations of Ni, Co, and Cr into the oral mucosal connective tissue were observed with SR-XRF, significant increases were only found in Ni from the pure Ni group and Cr from the Co-Cr group. Furthermore, Ni and Co were estimated as hydrated ions while Cr was estimated in oxide form through X-ray absorption fine structure (XAFS) analysis.


Assuntos
Mucosa Bucal/metabolismo , Animais , Ligas de Cromo/química , Feminino , Microscopia de Fluorescência , Níquel/química , Aparelhos Ortodônticos , Ratos , Ratos Wistar , Espectrometria por Raios X , Espectrofotometria Atômica , Titânio/química , Oligoelementos/química , Espectroscopia por Absorção de Raios X
12.
Dent Mater J ; 34(1): 114-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25748467

RESUMO

Most orthodontic equipment is fabricated from alloys such as stainless steel, Co-Cr and Ni-Ti because of their excellent elastic properties. In recent years, increasing esthetic demands, metal allergy and interference of metals with magnetic resonance imaging have driven the development of non-metallic orthodontic materials. In this study, we assessed the feasibility of using three super engineering plastics (PEEK, PES and PVDF) as orthodontic wires. PES and PVDF demonstrated excellent esthetics, although PEEK showed the highest bending strength and creep resistance. PEEK and PVDF showed quite low water absorption. Because of recent developments in coloration of PEEK, we conclude that PEEK has many advantageous properties that make it a suitable candidate for use as an esthetic metal-free orthodontic wire.


Assuntos
Cetonas/química , Fios Ortodônticos , Polietilenoglicóis/química , Polímeros/química , Polivinil/química , Sulfonas/química , Análise do Estresse Dentário , Elasticidade , Estudos de Viabilidade , Teste de Materiais , Propriedades de Superfície , Resistência à Tração
13.
Dent Mater J ; 33(5): 638-47, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25273043

RESUMO

Titanium (Ti) is widely used for oral cavity biomedical devices. However, because it penetrates the mucosa and exists partially external to the tissue, it sometimes induces tissue inflammation, minor infection, or peri-implantitis due to oral bacteria after implantation and causes serious consequences. We have previously shown that poly(ethylene glycol) (PEG)- electrodeposited Ti inhibits bacterial adhesion and biofilm formation. However, the effect of the PEG coating in body fluid is still unclear. In this study, we investigated bacterial colony morphology and biofilm formation on PEG-electrodeposited Ti in comparison with untreated Ti in the presence of saliva. After 48 h incubation, Streptococcus mutans biofilms adhered on the untreated Ti were rigid and cohesive, while those on the PEG-electrodeposited were loose and were easily washed off. These results indicate electrodeposited-PEG layers inhibit the biofilm formation on Ti in the presence of saliva.


Assuntos
Biofilmes , Polietilenoglicóis/química , Saliva/metabolismo , Titânio/química , Humanos , Microscopia Eletrônica de Varredura , Propriedades de Superfície
14.
Acta Biomater ; 9(9): 8433-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23707948

RESUMO

Susceptibility artifacts generated in magnetic resonance (MR) images were quantitatively evaluated for various metals using a three-dimensional (3-D) artifact rendering to demonstrate the correlation between magnetic susceptibility and artifact volume. Ten metals (stainless steel, Co-Cr alloy, Nb, Ti, Zr, Mo, Al, Sn, Cu and Ag) were prepared, and their magnetic susceptibilities measured using a magnetic balance. Each metal was embedded in a Ni-doped agarose gel phantom and the MR images of the metal-containing phantoms were taken using 1.5 and 3.0 T MR scanners under both fast spin echo and gradient echo conditions. 3-D renderings of the artifacts were constructed from the images and the artifact volumes were calculated for each metal. The artifact volumes of metals decreased with decreasing magnetic susceptibility, with the exception of Ag. Although Sn possesses the lowest absolute magnetic susceptibility (1.8×10(-6)), the artifact volume from Cu (-7.8×10(-6)) was smaller than that of Sn. This is because the magnetic susceptibility of Cu was close to that of the agarose gel phantom (-7.3×10(-6)). Since the difference in magnetic susceptibility between the agarose and Sn is close to that between the agarose and Ag (-17.5×10(-6)), their artifact volumes were almost the same, although they formed artifacts that were reversed in all three dimensions.


Assuntos
Artefatos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Metais/análise , Metais/química , Interpretação de Imagem Assistida por Computador/instrumentação , Campos Magnéticos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Orthodontics (Chic.) ; 13(1): 216-25, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22567635

RESUMO

AIM: An onplant is an orthodontic anchorage device fixed to the bone surface with osseointegration. Compared with implants, the onplant has fewer limitations regarding placement and is less invasive. The purpose of this study was to clarify the effect of bone-surface treatment and the fixing method of a newly designed smaller-sized onplant and establish a prospective surgical procedure for placement of the onplant. METHODS: Thirty-eight onplants were placed in six beagle dogs. The bone surface was planed where the cortical bone was thick and reducible (bone-planed). Where the cortical bone was thin and uneven, a filling was inserted in the space between the onplant and bone (filled). The onplant was fixed to the bone in one of two ways: using a membrane that covered the onplant and fixing the membrane with titanium pins (membrane-fixed) or fixing the onplant directly to the bone using the same titanium pins (pin-fixed). RESULTS: Twelve weeks later, all the onplants were osseointegrated. The bone-planed group showed significantly (P < .05) larger shear stress than the filled groups. In the bone-planed group, the pin-fixed group showed significantly (P < .05) larger shear stress than the membrane-fixed group. The shear stresses were considered strong enough to function in orthodontic treatment. CONCLUSION: The effect of the bone-surface treatment and the onplant-fixing method on the shear stress was clarified, and the findings in the present study may be useful for the improvement of surgical procedures for orthodontic onplants.


Assuntos
Osso e Ossos , Osseointegração , Animais , Implantes Dentários , Procedimentos de Ancoragem Ortodôntica/instrumentação , Estudos Prospectivos , Titânio
16.
Am J Orthod Dentofacial Orthop ; 138(3): 323-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20816302

RESUMO

INTRODUCTION: The purpose of this study was to clarify the frontal chewing patterns of various crossbite malocclusions. METHODS: A mandibular kinesiograph was used to record the masticatory movements of 106 subjects (ages, 12-35 years) with crossbite malocclusion and 22 subjects (ages, 16-30 years) with normal occlusion. The chewing patterns were classified into 8 chewing types according to the cycle shape of the frontal incisor point movement. The crossbite subjects were divided into 5 groups by the anteroposterior position of the crossbite, and then the subjects with posterior crossbite were divided into 3 groups by the transverse position of the crossbite. The Mann-Whitney U test was used to compare the frequency of each chewing type between any crossbite group and the control group; and between the various crossbite groups. RESULTS: In the crossbite groups, normal chewing occurred much less often than in subjects with normal occlusion. In the posterior crossbite group, reverse chewing was greater (P = 0.002), and normal chewing was less frequent (P = 0.001) compared with the anterior crossbite group. When accompanied by mandibular shift, mandibular prognathism, arch crossbite, in the crossbite or shift side, reverse type, and reverse-crossing type occurred more often than in contralateral side. CONCLUSIONS: In the frontal plane, patients with posterior crossbite might have more abnormal chewing types than those with anterior crossbite, and posterior crossbite could contribute to the high frequency of reverse and reverse-crossing chewing types, especially when accompanied by mandibular shift, mandibular prognathism, or arch crossbite.


Assuntos
Má Oclusão/fisiopatologia , Mastigação/fisiologia , Adolescente , Adulto , Dente Pré-Molar/fisiopatologia , Criança , Arco Dental/fisiopatologia , Oclusão Dentária , Feminino , Humanos , Incisivo/fisiopatologia , Masculino , Mandíbula/fisiopatologia , Dente Molar/fisiopatologia , Dente Serotino/fisiopatologia , Prognatismo/fisiopatologia , Adulto Jovem
17.
Angle Orthod ; 78(6): 1015-22, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18947276

RESUMO

OBJECTIVE: To clarify the influence of occlusal hypofunction on the integrity of gingival tissue and gingival extracellular matrix biosynthesis. MATERIALS AND METHODS: Thirteen-week-old male Wistar rats were divided into two groups. To eliminate occlusal forces, all the right maxillary molars were extracted in the hypofunctional group. The control group was anesthetized but not subjected to surgery. The rats were killed at 2 and 4 weeks after the procedure, and the lower right second molars were prepared for histological analysis. To investigate the effect of occlusal hypofunction on collagen biosynthesis, the expression of connective tissue growth factor (CTGF) and lysyl oxidase (LOX) was determined by immunohistochemistry as well as histological examination by hematoxylin and eosin staining. RESULTS: Disorientation of the collagen fibers, proliferation of the connective tissue fibroblasts, and enlargement of epithelial intercellular gaps were observed in gingival tissue of rat molars with experimental occlusal hypofunction. Immunohistochemically, the expression of CTGF and LOX was increased significantly (P < .05) in the hypofunctional group. CONCLUSION: These results suggest that occlusal hypofunction can affect the structural integrity and the expression of CTGF and LOX in gingival tissue.


Assuntos
Doenças da Gengiva/etiologia , Má Oclusão/complicações , Atrofia Periodontal/etiologia , Animais , Força de Mordida , Proliferação de Células , Colágeno/biossíntese , Fator de Crescimento do Tecido Conjuntivo/análise , Células Epiteliais/patologia , Matriz Extracelular/metabolismo , Espaço Extracelular , Fibroblastos/patologia , Gengiva/patologia , Imuno-Histoquímica , Masculino , Maxila , Dente Molar/cirurgia , Proteína-Lisina 6-Oxidase/análise , Ratos , Ratos Wistar , Extração Dentária
18.
Angle Orthod ; 78(3): 495-501, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18416609

RESUMO

OBJECTIVE: To investigate how the preapplication of orthodontic forces to the donor teeth affects the periodontal healing after transplantation. MATERIALS AND METHODS: The orthodontic force (1.5 cN) was applied to the maxillary right molars of 6-week-old male Spraque-Dawley rats (n = 21) in the experimental side, and the left side of the same animals was used as the control. After 7 days, both right and left maxillary second molars were extracted or replanted. Periodontal conditions were evaluated in the histological specimens 7 days after applying orthodontic force (before and after extraction) and 14 days after replantation. RESULTS: The application of orthodontic force for 7 days significantly increased the periodontal ligament (PDL) space and also the width of the alveolar socket, which resulted in a rich attached PDL to the root surface of the extracted teeth. Significantly more root resorption was also detected in the control side without preapplication of orthodontic force 14 days after replantation. This root resorption might involve in the disruption of the PDL. CONCLUSION: These results suggested that the preapplication of orthodontic force to the donor teeth increased the PDL width and eased the extraction, which might decrease root resorption after replantation.


Assuntos
Dente Molar/fisiopatologia , Fios Ortodônticos , Periodonto/fisiopatologia , Reimplante Dentário , Fosfatase Ácida/análise , Processo Alveolar/patologia , Processo Alveolar/fisiopatologia , Animais , Biomarcadores/análise , Isoenzimas/análise , Masculino , Modelos Animais , Dente Molar/patologia , Dente Molar/cirurgia , Osteoclastos/patologia , Periodonto/patologia , Ratos , Ratos Sprague-Dawley , Reabsorção da Raiz/etiologia , Reabsorção da Raiz/patologia , Estresse Mecânico , Fosfatase Ácida Resistente a Tartarato , Fatores de Tempo , Ápice Dentário/patologia , Ápice Dentário/fisiopatologia , Extração Dentária , Raiz Dentária/patologia , Raiz Dentária/fisiopatologia , Alvéolo Dental/patologia , Alvéolo Dental/fisiopatologia , Cicatrização/fisiologia
19.
J Med Dent Sci ; 55(1): 129-35, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19845158

RESUMO

Occlusal stimuli and the periodontal healing of replanted teeth have been reported to be related. However, the mechanism for preventing dentoalveolar ankylosis remains unclear. Basic fibroblast growth factor (bFGF/FGF-2) is considered as a key factor in wound healing. The purpose of this study was to evaluate the relationship between occlusal stimuli, bFGF, and the periodontal healing after tooth replantation. Five-week-old male rats were divided into non-occluded, occluded, and recovery groups. The right maxillary first molars were replanted in all groups, and the left maxillary first molars in the 2-week occluded group without replantation were served as nontreated. An anterior bite plate was attached to the maxillary and mandibular incisors to produce occlusal hypofunction in the non-occluded group and was then removed after 1 week in the recovery group. Histological observations were performed after 1 and 2 weeks of the experimental period. After 2 weeks, the non-occluded group had detectable ankylosis and obvious periodontal tissue stricture. Meanwhile, the occluded and recovery groups showed enlarged and thickened periodontia without ankylosis. The number of bFGF-positive cells in the occluded and recovery groups significantly increased as compared to in the non-occluded group. These results suggest that occlusal stimuli enhance the production of bFGF in the periodontal healing of replanted teeth and prevent dentoalveolar ankylosis.


Assuntos
Fator 2 de Crescimento de Fibroblastos/biossíntese , Mastigação/fisiologia , Ligamento Periodontal/fisiologia , Regeneração , Anquilose Dental/prevenção & controle , Reimplante Dentário , Processo Alveolar/fisiologia , Animais , Força de Mordida , Regeneração Óssea , Proliferação de Células , Análise do Estresse Dentário , Fator 2 de Crescimento de Fibroblastos/análise , Fator 2 de Crescimento de Fibroblastos/fisiologia , Imuno-Histoquímica , Masculino , Ligamento Periodontal/citologia , Ratos , Ratos Sprague-Dawley , Anquilose Dental/etiologia , Reimplante Dentário/efeitos adversos
20.
Angle Orthod ; 77(3): 549-56, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17465669

RESUMO

This case report describes the treatment of a Japanese girl aged 11 years 10 months who had a severe Class III malocclusion with a concave facial profile. She presented hypodivergent skeletal pattern with a -4.0-mm anterior crossbite and a deep overbite. She also had facial asymmetry attributed partly to the lateral mandibular shift to avoid incisal interferences. The treatment plan included a monoblock appliance, rapid palatal expansion, and fixed edgewise appliances at the final stage. The monoblock appliance was used to redirect the growth of the mandible to a clockwise direction and simultaneously correct the incisal relationships along with fixed edgewise appliances. Good incisal relationships were achieved, and facial esthetics was greatly improved after 28 months of treatment. Stability of the treatment result was excellent in the 3-year 9-month follow-up at the age of 18.


Assuntos
Assimetria Facial/terapia , Má Oclusão Classe III de Angle/terapia , Aparelhos Ortodônticos , Ortodontia Corretiva/métodos , Cefalometria , Criança , Estética Dentária , Face/anatomia & histologia , Feminino , Humanos , Má Oclusão Classe III de Angle/diagnóstico por imagem , Mandíbula/crescimento & desenvolvimento , Ortodontia Corretiva/instrumentação , Técnica de Expansão Palatina , Radiografia
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