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1.
Angle Orthod ; 89(4): 630-636, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30730198

RESUMO

OBJECTIVES: To evaluate the Interleukin-4 (IL-4), bone-specific alkaline phosphatase (BALP), and C-telopeptide of type I collagen (CTX-I) levels in peri-miniscrew crevicular fluid (PMCF) during orthodontic tooth movement between 75 and 150 g of distalization force. MATERIALS AND METHODS: Thirty miniscrews were placed bilaterally between the maxillary second premolars and first molars. The right and the left maxillary canines were moved distally using either 75 or 150 g of force. PMCF samples were collected before loading (T0); at 2 hours (T1) and 24 hours (T2) later; and on days 7 (T3), 14 (T4), 21 (T5), 30 (T6), and 90 (T7) after force application. Enzyme-linked immunosorbent assay kits were used to determine BALP, CTX-I, and IL-4 levels. RESULTS: There was no significant difference between the force groups at all time points with respect to BALP, CTX-I, and IL-4 levels (P > .05). There was no significant difference among time points for the two force groups in terms of BALP and IL-4 levels (P > .05). The CTX-I level at T3 was significantly higher than at T0 for both force groups (P < .05). CONCLUSIONS: Both 75 g and 150 g of orthodontic force are within optimal force limits, and there is no difference in biochemical markers of bone turnover.


Assuntos
Parafusos Ósseos , Colágeno Tipo I , Interleucina-4 , Peptídeos , Técnicas de Movimentação Dentária , Fosfatase Alcalina , Fenômenos Biomecânicos , Remodelação Óssea , Colágeno Tipo I/metabolismo , Líquido do Sulco Gengival , Humanos , Interleucina-4/metabolismo , Procedimentos de Ancoragem Ortodôntica , Peptídeos/metabolismo
2.
J Craniofac Surg ; 27(3): 571-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27092908

RESUMO

The repair of cleft lips has an important place in plastic and reconstructive surgery. In the treatment of these deformities, the aim was to restore the normal lip morphology in the cleft area as well as repairing any coexisting nasal deformities. Various methods are in use for this purpose. One of the most commonly employed surgical methods is Millard repair. However, this method may lead to additional scarring in the alar base on the cleft side subsequent to the incision. In this study, the results obtained from a group who have been applied alar base incisions during the modified Millard repair are compared to a group who have undergone intranasal wide dissections.The patients enrolled in the study were randomized into 2 groups. The first group were applied the modified Millard repair. In the second group, the rotation, advancement, and C-flaps were prepared according to Millard surgical repair technique; however, instead of an alar base and nasofacial groove incision on the cleft side, a nasal and maxillary supraperiosteal wide dissection was made through the incision in the mucosa of the nostril.The intranasal dissection performed during the study was observed to provide the targeted outcome and a more satisfactory cosmetic result through the modified Millard repair. In conclusion, the authors are of the opinion that the limited alar base incision and the wide supraperiosteal dissection performed in patients with cleft lips is an alternative method that can be employed in a wide range of patients.


Assuntos
Anormalidades Múltiplas , Fenda Labial/cirurgia , Nariz/anormalidades , Rinoplastia/métodos , Retalhos Cirúrgicos , Administração Intranasal , Feminino , Humanos , Lactente , Masculino , Nariz/cirurgia , Fatores de Tempo
3.
Korean J Orthod ; 43(3): 134-40, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23814708

RESUMO

OBJECTIVE: To evaluate lower incisor position and bony support between patients with Class II average- and high-angle malocclusions and compare with the patients presenting Class I malocclusions. METHODS: CBCT records of 79 patients were divided into 2 groups according to sagittal jaw relationships: Class I and II. Each group was further divided into average- and high-angle subgroups. Six angular and 6 linear measurements were performed. Independent samples t-test, Kruskal-Wallis, and Dunn post-hoc tests were performed for statistical comparisons. RESULTS: Labial alveolar bone thickness was significantly higher in Class I group compared to Class II group (p = 0.003). Lingual alveolar bone angle (p = 0.004), lower incisor protrusion (p = 0.007) and proclination (p = 0.046) were greatest in Class II average-angle patients. Spongious bone was thinner (p = 0.016) and root apex was closer to the labial cortex in high-angle subgroups when compared to the Class II average-angle subgroup (p = 0.004). CONCLUSIONS: Mandibular anterior bony support and lower incisor position were different between average- and high-angle Class II patients. Clinicians should be aware that the range of lower incisor movement in high-angle Class II patients is limited compared to average- angle Class II patients.

4.
Korean J Orthod ; 43(2): 83-95, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23671833

RESUMO

OBJECTIVE: To evaluate the changes in cortical bone thickness, alveolar bone height, and the incidence of dehiscence and fenestration in the surrounding alveolar bone of posterior teeth after rapid maxillary expansion (RME) treatment using cone-beam computed tomography (CBCT). METHODS: The CBCT records of 20 subjects (9 boys, mean age: 13.97 ± 1.17 years; 11 girls, mean age: 13.53 ± 2.12 year) that underwent RME were selected from the archives. CBCT scans had been taken before (T1) and after (T2) the RME. Moreover, 10 of the subjects had 6-month retention (T3) records. We used the CBCT data to evaluate the buccal and palatal aspects of the canines, first and second premolars, and the first molars at 3 vertical levels. The cortical bone thickness and alveolar bone height at T1 and T2 were evaluated with the paired-samples t-test or the Wilcoxon signed-rank test. Repeated measure ANOVA or the Friedman test was used to evaluate the statistical significance at T1, T2, and T3. Statistical significance was set at p < 0.05. RESULTS: The buccal cortical bone thickness decreased gradually from baseline to the end of the retention period. After expansion, the buccal alveolar bone height was reduced significantly; however, this change was not statistically significant after the 6-month retention period. During the course of the treatment, the incidence of dehiscence and fenestration increased and decreased, respectively. CONCLUSIONS: RME may have detrimental effects on the supporting alveolar bone, since the thickness and height of the buccal alveolar bone decreased during the retention period.

5.
Eur J Orthod ; 35(5): 555-62, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21734255

RESUMO

The aim of this study was to evaluate the relationship between the tongue volume and lower incisor irregularity, using cone-beam computed tomography (CBCT), and to identify the possible gender differences. CBCT images of 60 patients between 16 and 36 years of age were selected from 1400 sets of images in the database. Tomography was carried out using iCAT® (Imaging Sciences International, Hatfield, Pennsylvania, USA) and segmentation was carried out by using Mimics 10.1 software (Materialise NV, Leuven, Belgium). The tongue volume was calculated by using the volume of the voxels from the scan and the number of voxels selected for a given mask. Lower incisor crowding was measured with the Little's irregularity index and divided into three groups: mild, moderate, and severe. Independent samples t-test, analysis of variance (ANOVA), and Tukey test were used at P < 0.05 level. Pearson correlation coefficients and linear regression model were calculated to determine the correlation between tongue volume and incisor irregularity. No significant gender dimorphism was found for the tongue volume (females: 28.13 ± 8.54 cm(3) and males: 31.02 ± 9.75 cm(3)). According to ANOVA, there was statistically significant difference in the tongue volume measurements among subjects with different levels of irregularity. Tukey analysis indicated that mild irregularity group (33.97 cm(3)) showed higher values for tongue volume than severe irregularity group (26.60 cm(3); P = 0.025). The relationship between incisor irregularity and tongue volume was evaluated for both genders and significant inverse correlation (r = -0.429; P = 0.029) was determined between lower incisor irregularity and tongue volume in males. In female group, no significant correlation was determined between tongue volume and incisor irregularity.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Incisivo/anormalidades , Má Oclusão Classe I de Angle/diagnóstico por imagem , Língua/anatomia & histologia , Adolescente , Adulto , Feminino , Humanos , Incisivo/diagnóstico por imagem , Masculino , Tamanho do Órgão , Caracteres Sexuais , Software , Língua/diagnóstico por imagem , Adulto Jovem
6.
Am J Orthod Dentofacial Orthop ; 142(5): 645-53, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23116505

RESUMO

INTRODUCTION: The aim of this study was to test the null hypothesis that increased irregularity of the mandibular incisors is associated with a reduction in the alveolar support on cone-beam computed tomographic sections. METHODS: From a sample of 1100 digital volumetric tomographs, 125 tomographs of subjects with Class I malocclusion (mean age, 21.6 ± 4.8 years) were selected for this study. An irregularity index was used to categorize these tomographs as having mild, moderate, or severe crowding. All tomographs were taken by using an iCAT (Imaging Sciences International, Hatfield, Pa) imaging device. The following parameters were measured on the sections corresponding to the 4 mandibular incisors with the iCAT software: height, thickness, and area of the entire symphysis; height, thickness, and area of the cancellous bone of the symphysis; and distance between the vestibular and lingual cortices. For the statistical evaluation, independent samples t test, analysis of variance, and the Tukey HSD test were used at an alpha level 0.05. The Pearson correlation coefficient and a simple linear regression were calculated to determine the relationship between mandibular anterior bony support and incisor crowding. RESULTS: Almost all mandibular anterior bone measurements were greater in the male subjects than in the female subjects (height of the mandibular symphysis, P <0.001; cancellous bone height, P <0.001). Female subjects with mild crowding had higher values for cancellous bone height (P = 0.025) and vestibular cancellous bone thickness (P = 0.004) than did those with severe crowding. However, no differences were detected in the male subjects. Additionally, significant correlations were determined between incisor crowding and thickness of the mandibular symphysis, cancellous bone thickness, and the vestibular part of cancellous bone thickness in female subjects. CONCLUSIONS: Significant relationships were found between the measures of mandibular incisor crowding and basal bone dimensions in female subjects. Except for the vestibular part of cancellous bone thickness, all mandibular incisor bone measurements were greater in the male subjects than in the female subjects.


Assuntos
Perda do Osso Alveolar/complicações , Incisivo/patologia , Má Oclusão Classe I de Angle/etiologia , Má Oclusão Classe I de Angle/patologia , Doenças Mandibulares/complicações , Adolescente , Adulto , Perda do Osso Alveolar/diagnóstico por imagem , Análise de Variância , Densidade Óssea , Cefalometria , Queixo/patologia , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Modelos Lineares , Masculino , Doenças Mandibulares/diagnóstico por imagem , Fatores Sexuais , Estatísticas não Paramétricas , Adulto Jovem
7.
Angle Orthod ; 82(5): 868-74, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22356702

RESUMO

OBJECTIVE: To test the null hypothesis that the presence of alveolar defects (dehiscence and fenestration) was not different among patients with different vertical growth patterns. MATERIALS AND METHODS: A total of 1872 teeth in 26 hyper-divergent (mean age: 24.4 ± 4.8 years), 27 hypo-divergent (mean age: 25.1 ± 4.5 years), and 25 normo-divergent (mean age: 23.6 ± 4.1 years) patients with no previous orthodontic treatment were evaluated using cone-beam computed tomography. Axial and cross-sectional views were evaluated with regard to whether dehiscence and/or fenestration on buccal and lingual surfaces existed or not. For statistical analysis, the Pearson chi-square test was used at a P < .05 significance level. RESULTS: According to the statistical analysis, the hypo-divergent group (6.56%) had lower dehiscence prevalence than the hyper-divergent (8.35%) and normo-divergent (8.18%) groups (P  =  .004). Higher prevalences of dehiscence and fenestration were found on buccal sides in all vertical growth patterns. While fenestration was a common finding for the maxillary alveolar region, dehiscence was a common finding in the mandible in all groups. CONCLUSION: The null hypothesis was rejected. Although the prevalence of fenestrations was not different, significant differences for dehiscences were found in patients with different vertical growth patterns.


Assuntos
Processo Alveolar/anormalidades , Ossos Faciais/crescimento & desenvolvimento , Mandíbula/anormalidades , Maxila/anormalidades , Dente/anatomia & histologia , Adulto , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/crescimento & desenvolvimento , Tomografia Computadorizada de Feixe Cônico , Ossos Faciais/diagnóstico por imagem , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Dente/diagnóstico por imagem
8.
Angle Orthod ; 82(1): 67-74, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21696298

RESUMO

OBJECTIVE: To test the null hypothesis that the presence of dehiscence and fenestration was not different among patients with skeletal Class I, II, and III malocclusions. MATERIALS AND METHODS: In this retrospective study, a total of 123 cone-beam computed tomography (CBCT) images were obtained with an iCAT scanner (Imaging Sciences International, Hatfield, Pa). Patients with normal vertical patterns were classified according to dental malocclusion and ANB angle. Class I comprised 41 patients-21 girls and 20 boys (mean age, 22.4 ± 4.5 years); Class II comprised 42 patients-22 girls and 20 boys (mean age, 21.5 ± 4.2 years); and Class III comprised 40 subjects-22 girls and 18 boys (mean age, 22.1 ± 4.5 years). A total of 3444 teeth were evaluated. Analysis of variance and Tukey's test were used for statistical comparisons at the P < .05 level. RESULTS: Statistical analysis indicated that the Class II group had a greater prevalence of fenestration than the other groups (P < .001). No difference was found in the prevalence of dehiscence among the three groups. Although fenestration had greater prevalence in the maxilla, more dehiscence was found in the mandible for all groups. In Class I, alveolar defects (dehiscence, fenestration) were matched relatively in both jaws. Furthermore, Class II and Class III subjects had more alveolar defects (41.11% and 45.02%, respectively) in the mandible. Dehiscences were seen with greater frequency in the mandibular incisors of all groups. CONCLUSION: The null hypothesis was rejected. Significant differences in the presence of fenestration were found among subjects with skeletal Class I, Class II, and Class III malocclusions. Fenestrations had greater prevalence in the maxilla, but more dehiscences were found in the mandible.


Assuntos
Perda do Osso Alveolar/patologia , Retração Gengival/etiologia , Má Oclusão/complicações , Tomografia Computadorizada por Raios X , Técnicas de Movimentação Dentária/efeitos adversos , Adolescente , Adulto , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Processo Alveolar/diagnóstico por imagem , Análise de Variância , Cefalometria , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Má Oclusão/classificação , Má Oclusão/patologia , Má Oclusão/terapia , Mandíbula , Maxila , Estatísticas não Paramétricas , Raiz Dentária/diagnóstico por imagem , Adulto Jovem
9.
Angle Orthod ; 82(3): 488-94, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21843038

RESUMO

OBJECTIVE: To evaluate the root resorption after rapid maxillary expansion (RME) via cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Records of 25 patients who had undergone RME with tooth-borne banded expander were obtained from the archive of the orthodontic department. CBCT data were reconstructed with surface and volume rendering, and the volumetric images were manipulated to display the root surfaces from various orientations. On these three-dimensional images, permanent first molars and first and second premolars were segmented, and their roots were isolated. Volumes of roots were calculated. The difference between pre-expansion and postexpansion root volumes was statistically evaluated with a paired-samples t-test. Also, the percentage of root volume loss was calculated for each root and statistically compared with each other with one-way analysis of variance at the P < .05 level. RESULTS: The difference between the pre-expansion and postexpansion root volumes was statistically significant for all roots investigated. Maximum volume decrease was observed for the mesiobuccal root of first molar teeth (18.60 mm(3)). It was determined that the distobuccal root of first molar teeth was less affected from the expansion procedure (9.47 mm(3)). No statistically significant difference was found for the percentage of root volume loss. CONCLUSION: Following RME treatment, significant root volume loss was observed for all investigated posterior teeth. However, the percentage of volume loss was not statistically different among roots.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Técnica de Expansão Palatina/efeitos adversos , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/etiologia , Análise de Variância , Criança , Análise do Estresse Dentário , Feminino , Humanos , Imageamento Tridimensional , Masculino , Estudos Retrospectivos , Reabsorção da Raiz/patologia , Técnica de Subtração
10.
Eur Arch Otorhinolaryngol ; 269(3): 711-20, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21947434

RESUMO

Cone beam computed tomography (CBCT) allows us to evaluate 3-dimensional (3D) morphology of the maxillofacial skeleton and also used in dentomaxillofacial imaging to solve complex diagnostic and treatment planning problems such as craniofacial fractures, temporamandibular dysfunctions or sinus imaging. CBCT uses a rectangular or round 2D detector, which allows a single rotation of the gantry to generate a scan of the entire region of interest. Technological and application-specific factors such as development of compact, relatively low-cost, high-quality, large, flat-panel detector arrays; the availability of low-cost computers with processing power sufficient for cone beam image reconstruction; the fabrication of highly efficient radiograph tubes capable of multiple exposures necessary for cone beam scanning at prices lower than those currently used for fan beam CT; and limited volume scanning (e.g., head and neck) eliminating the need for subsecond gantry rotation speeds make this possible. The objective of this study is to review published evidence for CBCT having an important role in ORL treatments. We aimed to review all the available literature about the CBCT imagination in ORL treatments. Systematic literature search was performed using PubMed and Ovid. Additional literature was retrieved from reference lists in the articles. Systematic analysis of the literature from 1998 to 2010 was performed. A total of 40 abstracts were evaluated independently by two members of the project group, and 38 articles were included in the review.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Otolaringologia/métodos , Otorrinolaringopatias/diagnóstico por imagem , Humanos
11.
Angle Orthod ; 81(6): 966-74, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21591969

RESUMO

OBJECTIVE: To test the hypotheses that (1) there is no difference in mandibular asymmetry between the crossbite and normal side in a unilateral crossbite group (UCG) and between the right and left sides in a bilateral crossbite group (BCG) and a control group (CG); and (2) there is no significant difference in mandibular asymmetry among crossbite groups and control group. MATERIALS AND METHODS: The cone-beam computed tomography scans of three groups were studied: (1) 15 patients (6 male, 9 female; mean age: 13.51 ± 2.03 years) with unilateral posterior crossbite; (2) 15 patients (8 male, 7 female; mean age: 13.36 ± 2.12 years) with bilateral posterior crossbite; and (3) 15 patients (8 male, 7 female; mean age: 13.46 ± 1.53 years) as a control group. Fourteen parameters (eight linear, three surface, and three volumetric) were measured. Side comparisons were analyzed with paired samples t-test, and for the intergroup comparison, analysis of variance (ANOVA) and Tukey tests were used at the P < .05 level. RESULTS: According to side comparisons, no statistically significant difference was found in the UCG. There were statistically significant differences in hemimandibular (P = .008) and ramal (P = .004) volumes for the BCG and in ramal height (P = .024) and body length (P = .021) for the CG. Intergroup comparisons revealed significant differences in hemimandibular (P = .002) and body volume (P < .001) for the normal side of the UCG and left sides of the other groups, and in angular unit length (P = .025) and condylar width (P = .007) for the crossbite side of the UCG and the right sides of the other groups. CONCLUSIONS: Contrary to UCG, CG and BCG were found to have side-specific asymmetry. Skeletal components of the mandible have significant asymmetry among the crossbite groups and the CG.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Assimetria Facial/diagnóstico por imagem , Má Oclusão/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Adolescente , Análise de Variância , Estudos de Casos e Controles , Cefalometria , Criança , Feminino , Humanos , Masculino , Má Oclusão/patologia , Estudos Retrospectivos , Estatísticas não Paramétricas
12.
World J Orthod ; 11(3): 278-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20877739

RESUMO

This is a report about the orthodontic treatment of a 13-year, 10-month-old boy with total ankyloglossia combined with a Class III occlusion. The patient's tongue was fixed to the floor of his mouth and could not be elevated at all. He had a maxillary deficiency and a mandibular protrusion with a negative overjet. However, he was able to retrude his mandible to an edge-to-edge position. Before orthodontic treatment, the ankyloglossia was surgically rectified. Orthodontic treatment was initiated to improve the patient's occlusion and facial appearance by correcting his retruded maxilla by means of a face mask, fixed appliances, and Class III elastics. This led to a functional occlusion and an acceptable facial appearance.


Assuntos
Má Oclusão Classe III de Angle/terapia , Língua/anormalidades , Adolescente , Anodontia/terapia , Cefalometria/métodos , Diastema/terapia , Estética Dentária , Aparelhos de Tração Extrabucal , Humanos , Masculino , Maxila/anormalidades , Placas Oclusais , Braquetes Ortodônticos , Planejamento de Assistência ao Paciente , Prognatismo/terapia , Língua/cirurgia , Dimensão Vertical
13.
Am J Orthod Dentofacial Orthop ; 137(3): 368-74, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20197174

RESUMO

INTRODUCTION: After fixed appliance treatment, one concern is to restore the enamel surface as closely to its original state as possible. A variety of cleanup processes are available, but all are time-consuming and carry some risk of enamel damage. The purpose of this study was to examine tooth surfaces restored with different cleanup protocols. METHODS: Ninety-nine premolars extracted for orthodontic purposes were used. The 2 materials tested were Sof-Lex disks (3 M ESPE AG, Seefeld, Germany) and fiberglass burs (Stain Buster, Carbotech, Ganges, France). These were used alone and in combination with high- and low-speed handpieces, with which they were also compared. Eight groups were ultimately tested. All groups were compared with intact enamel, which served as the control group. From each group, 10 samples were examined with profilometry and 1 with scanning electron microscopy. Adhesive remnant index scores were recorded to ensure equal distributions for the groups. The time required for the cleanup processes and profilometry test results were also recorded. RESULTS: The fastest procedure was performed with high-speed handpieces, followed by low-speed handpieces. Sof-Lex disks and fiberglass burs required more time than carbide burs but did not result in significantly longer times for the cleanup procedure when combined with tungsten carbide-driven low- or high-speed handpieces or when used alone with low-speed handpieces. Although Sof-Lex disks were the most successful for restoring the enamel, it was not necessary to restore the enamel to its original surface condition. Generally, all enamel surface-roughness parameters were increased when compared with the values of intact enamel. The average roughness and maximum roughness depth measurements with Sof-Lex disks were statistically similar to measurements of intact enamel. CONCLUSIONS: No cleanup procedure used in this study restored the enamel to its original roughness. The most successful was Sof-Lex disks, which restored the enamel closer to its original roughness.


Assuntos
Esmalte Dentário/lesões , Restauração Dentária Permanente/métodos , Microabrasão do Esmalte/instrumentação , Aparelhos Ortodônticos/efeitos adversos , Microabrasão do Esmalte/métodos , Humanos , Microscopia Eletrônica de Varredura , Propriedades de Superfície
14.
Eur J Orthod ; 31(3): 271-5, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19233930

RESUMO

The purpose of this ex vivo study was to compare the bond strengths and modes of failure of brackets bonded with three self-etching products [Adper Prompt L-Pop (3M Espe), Futurabond NR (Voco) and Transbond Plus (3M Unitek)] and a conventional 38 per cent phosphoric acid-etching system Etch-Rite (Pulpdent Corp.) at two different time points. Ninety-six defect-free premolars were randomly allocated to eight groups (n = 12). The etching procedure was carried out according to the manufacturers' instructions. The shear bond strengths (SBSs) were measured after storage in distilled water for 12 and 24 hours. The brackets were debonded using a universal testing machine with a cross-head speed of 0.5 mm/minute. Multiple comparisons of the SBSs for the different etching types were performed using analysis of variance. The chi-square test was used to evaluate differences in adhesive remnant index (CARI) scores among the groups. The differences between SBSs analysed at 12 and 24 hours were not significantly different. Although a significant difference (P < 0.01) was observed with conventional and self-etching primer (SEP) adhesive systems, SEP revealed bond strengths higher than clinically accepted limits (6-8 MPa). SEP systems can achieve successful orthodontic bond strengths. The rate of development of the bond strength must be determined to ensure sufficient maturation of orthodontic adhesives before functional loading.


Assuntos
Condicionamento Ácido do Dente/métodos , Colagem Dentária , Nanocompostos/química , Cimentos de Resina/química , Lâmpadas de Polimerização Dentária , Ligas Dentárias/química , Esmalte Dentário/ultraestrutura , Análise do Estresse Dentário/instrumentação , Falha de Equipamento , Humanos , Metacrilatos/química , Braquetes Ortodônticos , Ácidos Fosfóricos/química , Resistência ao Cisalhamento , Aço Inoxidável/química , Estresse Mecânico , Propriedades de Superfície , Fatores de Tempo , Água/química
15.
Am J Orthod Dentofacial Orthop ; 134(2): 193-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18675199

RESUMO

INTRODUCTION: The purposes of this study were to assess the shear bond strength, the surface characteristics, and the adhesive remnant index scores of teeth prepared for bonding with erbium, chromium doped: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser etching, and to compare laser etching with phosphoric-acid etching and a self-etching primer. METHODS: Sixty-four premolars, extracted for orthodontic purposes, were randomly divided into 4 groups, and a different method was used to prepare the tooth enamel in each group for bonding: irradiation for 15 seconds with a 0.75-W Er,Cr:YSGG laser; irradiation for 15 seconds with a 1.5-W Er,Cr:YSGG laser; etching with 37% phosphoric acid; application of a self-etching primer. After surface preparation, standard edgewise stainless steel premolar brackets were bonded; 1 tooth in each group was not bonded and was examined under a scanning electron microscopic. The brackets were debonded 24 hours later; shear bond strengths were measured, and adhesive remnant index scores were recorded. RESULTS: Irradiation with the 0.75-W laser produced lower shear bond strengths than the other methods. No statistically significant differences were found between 1.5-W laser irradiation, phosphoric-acid etching, and self-etching primer. Adhesive remnant scores were compared with the chi-square test, and statistically significant differences were found between all groups; when the 0.75-W laser irradiation group was excluded, no statistically significant differences were observed. CONCLUSIONS: Irradiation with a 1.50-W laser produced sufficient etching for orthodontic bonding, but irradiation with the 0.75-W laser did not.


Assuntos
Colagem Dentária , Esmalte Dentário/efeitos da radiação , Corrosão Dentária/métodos , Lasers , Análise de Variância , Esmalte Dentário/ultraestrutura , Análise do Estresse Dentário , Humanos , Dente Molar , Ácidos Fosfóricos/efeitos adversos , Resistência ao Cisalhamento , Propriedades de Superfície
16.
Eur J Orthod ; 30(2): 183-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18263892

RESUMO

The purpose of the study was to determine if sandblasted and laser-irradiated enamel may be viable alternatives to acid etching for molar tube bonding. Seventy-seven molar teeth extracted for periodontal reasons were used. Seventy teeth underwent shear bond strength (SBS) testing and the remaining seven were examined under scanning electron microscopy (SEM). Adhesive remnant index (ARI) scores were also considered. An erbium, chromium-doped:yttrium-scandium-gallium-garnet (Er, Cr: YSGG) laser was used for enamel etching. Sandblasted and laser-irradiated enamel surfaces with different power outputs (0.5, 0.75, 1, 1.5, and 2 W) were compared with conventional phosphoric acid etching. Descriptive statistics, including mean, standard deviation, and minimum and maximum values, were calculated for each group. Multiple comparisons of the SBS of different etching types were performed by analysis of variance testing. The chi-square test was used to evaluate differences in ARI scores between groups. Acid-etched, 1-, 1.5-, and 2-W laser irradiation groups demonstrated a clinically acceptable mean SBS (7.65 +/- 1.38, 6.69 +/- 1.27, 7.13 +/- 1.67, 7.17 +/- 1.69 MPa, respectively). Irradiation with an output of 0.5 and 0.75 W and sandblasting of the enamel showed a lower SBS than the other groups (2.94 +/- 1.98, 4.16 +/- 2.87, 2.01 +/- 0.64 MPa, respectively). SEM evaluation of 1, 1.5, and 2 W laser irradiation revealed similar etching patterns to acid etching. Sandblasting and 0.5, and 0.75 W laser etching were not able to etch enamel in preferential patterns. Laser irradiation at 1.5 and 2 W was able to etch enamel. More adhesive was left on the enamel surface with low-power laser irradiation. Sandblasting and low-power laser irradiation (0.5, 0.75, and 1 W) are not capable of etching enamel suitable for orthodontic molar tube bonding, but 1.5- and 2-W laser irradiation may be an alternative to conventional acid etching.


Assuntos
Colagem Dentária/métodos , Aparelhos Ortodônticos , Condicionamento Ácido do Dente , Abrasão Dental por Ar , Análise de Variância , Distribuição de Qui-Quadrado , Esmalte Dentário , Análise do Estresse Dentário , Humanos , Lasers de Estado Sólido , Dente Molar , Cimentos de Resina , Resistência ao Cisalhamento
17.
Eur J Orthod ; 30(1): 61-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17906307

RESUMO

This study examined the effects of rapid palatal expansion (RPE) and maxillary protraction headgear therapy in 18 patients with a skeletal Class III malocclusion (11 girls and seven boys; mean age 10.9 years) on upper airway dimensions compared with an untreated control group (nine girls and eight boys; mean age 10.9 years). Pre- and post-treatment cephalometric radiographs were traced and analysed at similar time intervals. The average treatment time was 6.94 +/- 0.56 months. Wilcoxon's test was used for intragroup comparisons and the Mann-Whitney U-test for intergroup comparisons. A significant increase occurred in the maxillary forward position. Mandibular forward movement and downward and backward rotation were inhibited. In addition, the upper incisors were proclined (P < 0.001), and the lower incisors were significantly retroclined (P < 0.05). When the treatment and control groups were compared, the upper airway linear measurements (pns-ad1, pns-ad2, APW-PPW, APW'-PPW') and the nasopharyngeal area had increased in the treatment group. These results demonstrated that maxillary expansion together with protraction of the maxilla improved naso- and oropharyngeal airway dimensions in the short term.


Assuntos
Má Oclusão Classe III de Angle/terapia , Maxila/patologia , Ortodontia Corretiva/métodos , Técnica de Expansão Palatina , Faringe/patologia , Aparelhos Ativadores , Cefalometria/métodos , Criança , Aparelhos de Tração Extrabucal , Feminino , Seguimentos , Humanos , Incisivo/patologia , Masculino , Mandíbula/patologia , Nasofaringe/patologia , Orofaringe/patologia , Técnica de Expansão Palatina/instrumentação , Rotação , Fatores de Tempo
18.
J Oral Pathol Med ; 37(1): 26-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18154574

RESUMO

The aim of this study was to assess quantitative and qualitative alterations in the carrier rate of Candida spp. in south-eastern Turkey among adolescents, and to investigate the effect of fixed orthodontic appliances on the Candida count in a 1-year follow-up study. In the first phase of the study, the oral Candida carriage rate of 72 patients was evaluated. Samples were collected from the dorsal surface of the tongue, the mid-palate and saliva. In the second phase of the study, 42 patients who were determined to be carriers of oral Candida were treated with fixed orthodontic appliances, and from these patients a second set of samples were collected from the saliva and the orthodontic brace surfaces of eight teeth adjacent to the enamel surfaces. The saliva samples were collected before and during orthodontic treatment at 1st, 6th and 12th month, and samples from the braces were collected during the 1st, 6th and 12th month of treatment. Forty-two of the 72 patients (58.5%) were oral Candida carriers. The distribution of Candida spp. in these patients was as follows: (i) Candida albicans was identified in 31 patients (73.8%), (ii) C. tropicalis, C. krusei and C. kefyr were found in three patients each (7.14%) and (iii) C. parapsilosis occurred in two patients (4.76%). During orthodontic treatment, the micro-organism count increased both in the saliva and on tooth surfaces. The results indicate that the prevalence of oral Candida spp. is high in young adults in south-eastern Turkey and that the Candida counts increase when braces are involved.


Assuntos
Candida/isolamento & purificação , Boca/microbiologia , Aparelhos Ortodônticos/microbiologia , Saliva/microbiologia , Adolescente , Adulto , Candidíase Bucal/microbiologia , Portador Sadio , Contagem de Colônia Microbiana , Feminino , Seguimentos , Humanos , Masculino , Estatísticas não Paramétricas , Turquia
19.
Am J Orthod Dentofacial Orthop ; 131(4): 447.e13-20, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17418707

RESUMO

INTRODUCTION: The aim of this study was to investigate the relationships between the stages of calcification of teeth and the cervical vertebral maturity stages in Turkish subjects. METHODS: A retrospective cross-sectional study was designed. The final study population consisted of 590 Turkish subjects. Statistical analysis of the data was performed with computer software. Spearman rank order correlation coefficients were used to assess the relationship between cervical vertebral and dental maturation. For a better understanding of the relationship between cervical vertebral maturation indexes and dental age, percentage distributions of the studied teeth were also calculated. RESULTS: Strict correlations were found between dental and cervical vertebral maturation of Turkish subjects. For males, the sequence from lowest to the highest was third molar, central incisor, canine, first premolar, second premolar, first molar, and second molar. For females, the sequence from lowest to the highest was third molar, canine, second premolar, first premolar, central incisor, first molar, and second molar. CONCLUSIONS: Dental maturation stages can be used as a reliable indicator of facial growth.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Determinação da Idade pelos Dentes/métodos , Vértebras Cervicais/crescimento & desenvolvimento , Calcificação de Dente/fisiologia , Dente/crescimento & desenvolvimento , Adolescente , Fatores Etários , Criança , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Fatores Sexuais , Dente/química , Dente/diagnóstico por imagem , Raiz Dentária/crescimento & desenvolvimento , Turquia
20.
Angle Orthod ; 77(1): 117-23, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17029548

RESUMO

OBJECTIVE: To test the shear bond strength, surface characteristics, and fracture mode of brackets that are bonded to enamel etched with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser operated at different power outputs: 0.5 W, 1 W, and 2 W. MATERIALS AND METHODS: Human premolars that had been extracted for orthodontic purposes were used. Enamel was etched with an Er,Cr:YSGG laser system operated at one of three power outputs or with orthophosphoric acid. RESULTS: The shear bond strength associated with the 0.5-W laser irradiation was significantly less than the strengths obtained with the other irradiations. Both the 1-W and 2-W laser irradiations were capable of etching enamel in the same manner. This finding was confirmed by scanning electron microscopy examination. The evaluation of adhesive-remnant-index scores demonstrated no statistically significant difference in bond failure site among the groups, except for the 0.5-W laser-etched group. Generally, more adhesive was left on the enamel surface with laser irradiation than with acid etching. CONCLUSION: The mean shear bond strength and enamel surface etching obtained with an Er,Cr: YSGG laser (operated at 1 W or 2 W for 15 seconds) is comparable to that obtained with acid etching.


Assuntos
Corrosão Dentária/métodos , Lasers , Análise de Variância , Dente Pré-Molar , Distribuição de Qui-Quadrado , Cromo , Colagem Dentária , Descolagem Dentária , Esmalte Dentário , Análise do Estresse Dentário , Érbio , Humanos , Microscopia Eletrônica de Varredura , Ácidos Fosfóricos , Resistência ao Cisalhamento , Propriedades de Superfície
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