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1.
Orthod Craniofac Res ; 26(2): 151-162, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35737876

RESUMEN

OBJECTIVE: To compare the transverse dental and skeletal changes in patients treated with bone-anchored palatal expander (bone-borne, BB) compared to patients treated with tooth and bone-anchored palatal expanders (tooth-bone-borne, TBB) using cone-beam computer tomography (CBCT) and 3D image analysis. METHODS: The sample comprised 30 patients with transverse maxillary discrepancy treated with two different types of appliances: bone-borne (Group BB) and tooth-bone-borne (Group TBB) expanders. CBCT scans were acquired before (T1) and after completion of maxillary expansion (T2); the interval was 5.4 ± 3.4 and 6.2 ± 2.1 months between the T1 and the T2 scans of Group TBB (tooth-bone-borne) and Group BB (bone-borne), respectively. Transverse, anteroposterior and vertical linear and angular three-dimensional dentoskeletal changes were assessed after cranial base superimposition. RESULTS: Both groups displayed marked transverse skeletal expansion with a greater ratio of skeletal to dental changes. Greater changes at the nasal cavity, zygoma and orbital levels were found in Group BB. A relatively parallel sutural opening in an anterior-posterior direction was observed in Group TBB; however, the Group BB presented a somewhat triangular (V-shaped) opening of the suture that was wider anteriorly. Small downward-forward displacements were observed in both groups. Asymmetric expansion occurred in approximately 50% of the patients in both groups. CONCLUSION: Greater skeletal vs dental expansion ratio and expansion of the circummaxillary regions were found in Group BB, the group in which a bone-borne expander was used. Both groups presented skeletal and dental changes, with a similar amount of posterior palate expansion. Asymmetric expansion was observed in both groups.


Asunto(s)
Técnica de Expansión Palatina , Diente , Humanos , Adulto Joven , Tomografía Computarizada de Haz Cónico/métodos , Maxilar/diagnóstico por imagen , Hueso Paladar
2.
Am J Orthod Dentofacial Orthop ; 161(6): 849-857, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35151529

RESUMEN

INTRODUCTION: The correction of maxillary transverse discrepancy is achieved by means of rapid maxillary expansion, which may be performed by conventional or surgically-assisted rapid maxillary expansion, and more recently, by miniscrew-assisted rapid palatal expansion (MARPE). This study assessed the bone thickness of the palate on cone-beam computed tomography (CBCT) images for placement of mini-implants and anchorage of MARPE. METHODS: The sample consisted of 223 CBCT scans from patients of both genders (137 females and 86 males) aged ≥18 years. By using the Image Studio software (Anne Solutions, São Paulo, Brazil), measurements of the bone thickness of the palate were performed bilaterally, as follows: in the axial plane, the bone thicknesses were determined in the anterior region (distal face of the first premolars) and the posterior region (distal face of the first molars), at 3 mm and 6 mm laterally to the midpalatal suture. So in the sagittal plane, the bone thicknesses of the palate were measured in these placements from the palatal cortical to the nasal floor cortical in the anterior region at 30°, 45°, and 90°. In the posterior region, the bone thickness was determined only at 90°. The statistical tests used were the Kruskal-Wallis H test (analysis of variance on ranks) with Dunn's post-hoc test and Mann-Whitney U test (P <0.05). RESULTS: The bone thickness of the palate in the anterior region varied from 8.57 mm in women to 11.28 mm in men at 3 mm from the midpalatal suture and from 7.99 mm in women to 10.47 mm in men at 6 mm for 30°; from 6.35 mm in women to 9.28 mm in men at 3 mm from the midpalatal suture and from 6.20 mm in women to 8.88 mm in men at 6 mm for 45°; from 4.51 mm in women to 6.85 mm in men at 3 mm from the midpalatal suture and from 4.29 mm in women to 6.64 mm in men at 6 mm for 90°. In the posterior region, the bone thickness varied from 2.93 mm (3 mm from the suture) to 1.78 mm (6 mm from the suture) for women and from 3.24 mm (3 mm from the suture) to 1.99 mm (6 mm from the suture) for men. In general, the bone thickness of the palate is greater in the anterior region at 3 mm from the midpalatal suture at 30°. CONCLUSIONS: There was high variability in the bone thickness of the palate among patients and in different areas. Therefore, it is necessary to make an individualized diagnosis of the patient and manufacture the MARPE appliance carefully by performing a prior evaluation of the palatal bone thickness by means of CBCT to determine the ideal sites and inclinations for placement of mini-implants.


Asunto(s)
Técnica de Expansión Palatina , Hueso Paladar , Adolescente , Adulto , Brasil , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Masculino , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Hueso Paladar/diagnóstico por imagen
3.
Am J Orthod Dentofacial Orthop ; 161(5): 666-678, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34980520

RESUMEN

INTRODUCTION: The objective was to determine the skeletal and dental changes with microimplant assisted rapid palatal expansion (MARPE) appliances in growing (GR) and nongrowing (NG) patients using cone-beam computed tomography and 3-dimensional imaging analysis. METHODS: The sample consisted of 25 patients with transverse maxillary discrepancy treated with a maxillary skeletal expander, a type of MARPE appliance. Cone-beam computed tomography scans were taken before and after maxillary expansion; the interval was 6.0 ± 4.3 months. The sample was divided into GR and NG groups using cervical vertebral and midpalatal suture maturation. Linear and angular 3-dimensional dentoskeletal changes were assessed after cranial base superimposition. Groups were compared with independent-samples t test (P <0.05). RESULTS: Both groups displayed marked transverse changes with a similar ratio of skeletal to dental transverse changes and parallel sutural opening from the posterior nasal spine-anterior nasal spine; a similar amount of expansion occurred in the anterior and the posterior regions of the maxilla. The maxilla expanded skeletally without rotational displacements in both groups. The small downward-forward displacements were similar in both groups, except that the GR group had a significantly greater vertical displacement of the canines (GR, 1.7 ±1.0 mm; NG, 0.6 ± 0.8 mm; P = 0.02) and anterior nasal spine (GR, 1.1 ± 0.6 mm; NG, 0.5 ± 0.5 mm; P = 0.004). CONCLUSIONS: Treatment of patients with MARPE appliance is effective in GR and NG patients. Although greater skeletal and dental changes were observed in GR patients, a similar ratio of skeletal to dental transverse changes was observed in both groups.


Asunto(s)
Técnica de Expansión Palatina , Diente , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Hueso Paladar
5.
Am J Orthod Dentofacial Orthop ; 148(6): 1010-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26672707

RESUMEN

INTRODUCTION: The aim of this study was to analyze the diagnostic performance of the cervical vertebral maturation (CVM) method in estimating accurately the stages of maturation of the midpalatal suture. METHODS: Cone-beam computed tomography (CBCT) images from 142 subjects (84 female, 58 male; mean age, 14.8 ± 9.7 years) were analyzed by 2 calibrated examiners to define, by visual analysis, the maturational stages of the cervical vertebrae and the midpalatal suture. These CBCT images were required by orthodontists and surgeons for diagnosis and treatment purposes. Positive likelihood ratios (LHRs) were calculated to evaluate the diagnostic performance of the CVM stages in identifying the maturational stages of the midpalatal suture. RESULTS: Positive LHRs greater than 10 were found for several cervical vertebral stages (CSs), including CS1 and CS2 for the identification of midpalatal suture stages A and B, CS3 for the diagnosis of midpalatal suture stage C, and CS5 for the assessment of midpalatal suture stages D and E. These positive LHRs indicated large and often conclusive increases in the likelihood that the CVM stages were associated with specific stages of midpalatal suture maturation. At CS4, there were a moderate positive LHR for stage C and low positive LHRs for stages D and E. CONCLUSIONS: Most CVM stages can be used for the diagnosis of the stages of maturation of the midpalatal suture, so that CBCT imaging may not be necessary in these patients. In the postpubertal period, however, an assessment of the midpalatal suture maturation using CBCT images may be indicated in deciding between conventional rapid maxillary expansion and surgically assisted rapid maxillary expansion. On the other hand, if the CVM stage cannot be assessed, chronologic age may be a viable alternative to predict some midpalatal suture stages (particularly the early stages).


Asunto(s)
Determinación de la Edad por el Esqueleto/estadística & datos numéricos , Vértebras Cervicales/crecimiento & desarrollo , Suturas Craneales/crecimiento & desarrollo , Hueso Paladar/crecimiento & desarrollo , Adolescente , Adulto , Anatomía Transversal/estadística & datos numéricos , Cefalometría/estadística & datos numéricos , Niño , Preescolar , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Funciones de Verosimilitud , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pubertad/fisiología , Sensibilidad y Especificidad , Adulto Joven
6.
Eur J Orthod ; 36(2): 192-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23736378

RESUMEN

AIM: To examine the long-term effects induced by treatment with the function regulator (FR-2) appliance 7 years post-treatment compared with untreated class II subjects. SUBJECTS AND METHODS: The FR-2 sample was collected prospectively and comprised 17 subjects (10 boys and 7 girls, mean age 10.8 years) who were treated with the FR-2 appliance for 1.7 years and re-evaluated 7.1 years after treatment. The step-by-step mandibular advancement was performed gradually (increments up to 3-4 mm), until a 'super class I' molar relationship was obtained. The control group consisted of 17 class II subjects (9 boys and 8 girls, mean age 11.3 years) with class II malocclusion, excessive overjet, and class II molar relationship, matched to the treated group as to ages at all times, gender distribution, and stages of skeletal maturity (evaluated by the cervical vertebral maturation method). The lateral cephalograms were analysed at T1 (initial), T2 (final), and T3 (7.1 years post-treatment). The compatibility between the groups and the comparisons of their changes at T1-T2, T2-T3, and T1-T3 intervals were examined by independent sample t-tests (P < 0.05). RESULTS: FR-2 treatment provided a significant improvement in the maxillomandibular relationship due to an increase in mandibular length compared with controls, which remained stable over time. Also overjet, overbite, and molar relationship corrections demonstrated stability. Among dentoalveolar changes, only the increased mesial movement of the mandibular molars in the FR-2 group demonstrated stability. CONCLUSIONS: Correction of class II malocclusion remained stable 7 years after FR-2 treatment mainly due to the stability of the skeletal changes.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Avance Mandibular/instrumentación , Aparatos Ortodóncicos Funcionales , Adolescente , Cefalometría/métodos , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Maloclusión Clase II de Angle/patología , Maloclusión Clase II de Angle/fisiopatología , Mandíbula/crecimiento & desarrollo , Avance Mandibular/métodos , Desarrollo Maxilofacial/fisiología , Diente Molar/patología , Sobremordida/terapia , Estudios Prospectivos
7.
Am J Orthod Dentofacial Orthop ; 144(5): 759-69, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24182592

RESUMEN

INTRODUCTION: In this study, we present a novel classification method for individual assessment of midpalatal suture morphology. METHODS: Cone-beam computed tomography images from 140 subjects (ages, 5.6-58.4 years) were examined to define the radiographic stages of midpalatal suture maturation. Five stages of maturation of the midpalatal suture were identified and defined: stage A, straight high-density sutural line, with no or little interdigitation; stage B, scalloped appearance of the high-density sutural line; stage C, 2 parallel, scalloped, high-density lines that were close to each other, separated in some areas by small low-density spaces; stage D, fusion completed in the palatine bone, with no evidence of a suture; and stage E, fusion anteriorly in the maxilla. Intraexaminer and interexaminer agreements were evaluated by weighted kappa tests. RESULTS: Stages A and B typically were observed up to 13 years of age, whereas stage C was noted primarily from 11 to 17 years but occasionally in younger and older age groups. Fusion of the palatine (stage D) and maxillary (stage E) regions of the midpalatal suture was completed after 11 years only in girls. From 14 to 17 years, 3 of 13 (23%) boys showed fusion only in the palatine bone (stage D). CONCLUSIONS: This new classification method has the potential to avoid the side effects of rapid maxillary expansion failure or unnecessary surgically assisted rapid maxillary expansion for late adolescents and young adults.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Suturas Craneales/crecimiento & desarrollo , Técnica de Expansión Palatina , Paladar Duro/crecimiento & desarrollo , Adolescente , Adulto , Factores de Edad , Anatomía Transversal , Densidad Ósea/fisiología , Niño , Preescolar , Suturas Craneales/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Masculino , Maxilar/crecimiento & desarrollo , Persona de Mediana Edad , Paladar Duro/diagnóstico por imagen , Adulto Joven
8.
Int J Orthod Milwaukee ; 23(3): 29-34, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23094556

RESUMEN

Abstract: There are many appliances that can be used to correct molar relationship, achieving upper molar distalization, in Class II malocclusion. This research aimed to study the dental effects promoted by lip bumper to retain maxillary molars that had previously been distalized using a Cetlin appliance in conjunction with headgear.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Diente Molar/fisiología , Aparatos Ortodóncicos , Retenedores Ortodóncicos , Técnicas de Movimiento Dental , Cefalometría , Niño , Aparatos de Tracción Extraoral , Femenino , Humanos , Masculino , Maxilar
9.
Clin Oral Investig ; 15(3): 357-60, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20336472

RESUMEN

The aim of the present study was to evaluate DNA damage (micronucleus) and cellular death (pyknosis, karyolysis, and karyorrhexis) in exfoliated buccal mucosa cells from individuals following digital lateral radiography. A total of 30 healthy patients (15 men and 15 women) indicated to the orthodontic therapy were submitted to digital lateral X-ray. Exfoliated oral mucosa cells were collected immediately before the X-ray exposure and after 10 days. The results pointed out no significant statistically differences (p > 0.05) of micronucleated oral mucosa cells. On the other hand, X-ray was able to increase other nuclear alterations closely related to cytotoxicity such as karyorrhexis, pyknosis, and karyolysis. In summary, these data indicate that exposure to digital lateral radiography may not be a factor that induced chromosomal damage, but it is able to promote cytotoxicity.


Asunto(s)
Núcleo Celular/efectos de la radiación , Mucosa Bucal/efectos de la radiación , Radiografía Dental Digital/efectos adversos , Muerte Celular , Daño del ADN , Femenino , Humanos , Masculino , Micronúcleos con Defecto Cromosómico , Pruebas de Micronúcleos , Mucosa Bucal/citología , Estadísticas no Paramétricas , Adulto Joven
10.
Am J Orthod Dentofacial Orthop ; 139(4 Suppl): e399-404, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21435548

RESUMEN

INTRODUCTION: The aim of the present study was to evaluate DNA damage (micronucleus) and cellular death (pyknosis, karyolysis, and karyorrhexis) in exfoliated buccal mucosa cells from adults after fixed orthodontic therapy. MATERIAL AND METHODS: A total of 23 healthy adults (10 men and 13 women) undergoing orthodontic therapy were included in this setting. RESULTS: The results pointed out no significant statistically differences (P >0.05) of micronucleated oral mucosa cells. In the same way, orthodontic therapy was not able to increase other nuclear alterations closely related to cytotoxicity such as karyorrhexis, pyknosis and karyolysis (P >0.05). CONCLUSION: In summary, these data indicate that orthodontic therapy may not be a factor that induces chromosomal damage, nor it is able to promote cytotoxicity. Since DNA damage and cellular death are important events during carcinogenic processes, especially in early phases, this study represents a correct evaluation with respect to real health risks induced by orthodontic devices.


Asunto(s)
Daño del ADN , Mucosa Bucal/efectos de los fármacos , Aparatos Ortodóncicos/efectos adversos , Adolescente , Adulto , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Aleaciones de Cromo/toxicidad , Femenino , Humanos , Cariometría , Masculino , Pruebas de Micronúcleos , Mucosa Bucal/citología , Níquel/toxicidad , Acero Inoxidable/toxicidad , Estadísticas no Paramétricas , Titanio/toxicidad , Adulto Joven
11.
Am J Orthod Dentofacial Orthop ; 139(4): 504-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21457861

RESUMEN

INTRODUCTION: The purpose of this study was to evaluate whether corrosion eluates obtained from commercially available orthodontic brackets are able to induce genetic damage in vitro. MATERIAL AND METHODS: Genotoxicity was assessed by the single cell gel (comet) assay using Chinese hamster ovary (CHO) cells. The following orthodontic metallic brackets were used: Morelli (Sorocaba, Brazil); Abzil (São José do Rio Preto, Brazil); Dentaurum (Pforzheim, Germany); and 3M Unitek (Puchheim, Germany). Each dental bracket was submitted to a corrosion process in a solution containing equal amounts of acetic acid and sodium chloride at 0.1 M concentration for 1, 3, 7, 14, 21, 35, and 70 days. CHO cells were exposed to eluates for 30 minutes at 37°C. The negative control was treated with the same solution used for corrosion process for 30 minutes at 37°C. Independent positive control was performed with methyl methanesulfonate (MMS) (Sigma Aldrich, St. Louis, Mo) at 1 ug/mL for 1 hour. RESULTS: None of the eluates was found to exhibit genotoxicity, regardless of the different commercial brands of orthodontic appliance used. CONCLUSIONS: In summary, our results indicate corrosion eluates obtained from orthodontic brackets do not induce genetic damage as assessed by single cell gel (comet) assay.


Asunto(s)
Células CHO/efectos de los fármacos , Aleaciones Dentales/química , Mutágenos/química , Soportes Ortodóncicos , Ácido Acético/química , Animales , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Corrosión , Cricetinae , Cricetulus , Daño del ADN , Aleaciones Dentales/farmacología , Relación Dosis-Respuesta a Droga , Ensayo de Materiales , Metilmetanosulfonato/efectos adversos , Mutágenos/efectos adversos , Mutágenos/farmacología , Cloruro de Sodio/química , Temperatura , Factores de Tiempo
12.
Angle Orthod ; 91(2): 187-194, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33351888

RESUMEN

OBJECTIVES: To evaluate whether the success of miniscrew-assisted rapid palatal expansion (MARPE), performed in patients with advanced bone maturation is related to factors such as midpalatal suture (MPS) maturation, age, sex, or bicortical mini-implant anchorage. MATERIALS AND METHODS: Twenty-eight cone beam computed tomography (CBCT) scans of adults and post-pubertal adolescents treated by MARPE were included in the sample. CBCT images before (T0) and after expansion (T1) were used to evaluate the skeletal changes and the success or failure of MARPE. Axial images of MPS were extracted from T0 and classified into one of the five maturation stages. The correlation between MARPE success and the factors of age, sex, MPS maturation, and bicortical mini-implant anchorage was investigated. RESULTS: Only the age showed a statistically significant negative correlation with MARPE success and all the skeletal measures. There was an 83.3% success rate among individuals aged 15 to 19 years, 81.8% from 20 to 29 years, and 20% from 30 to 37 years. MPS maturation showed a negative correlation with the expansion effect. Subjects with stages B or C of MPS maturation showed a 100% success rate, followed by stage D (62.5%) and stage E (58.3%). CONCLUSIONS: As age increased, there was a decrease in MARPE success and the skeletal effects of maxillary expansion. Sex and bicortical mini-implant anchorage were not shown to be relevant factors. There was no correlation between MPS maturation and MARPE success; however, it was observed that all cases of MARPE failure were classified as stage D or E of MPS maturation.


Asunto(s)
Maxilar , Técnica de Expansión Palatina , Adolescente , Adulto , Tomografía Computarizada de Haz Cónico , Suturas Craneales , Humanos , Maxilar/diagnóstico por imagen , Hueso Paladar/diagnóstico por imagen , Adulto Joven
13.
Clin Oral Investig ; 14(6): 669-74, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19798520

RESUMEN

The aim of the present study was to comparatively evaluate DNA damage (micronucleus) and cellular death (pyknosis, karyolysis, and karyorrhexis) in exfoliated oral mucosa cells from smokers and non-smokers submitted to dental X-ray using two anatomic sites: buccal mucosa and lateral border of the tongue. A total of 15 heavy smokers and 17 non-smokers were submitted to panoramic dental radiography for orthodontic reasons. Individuals had epithelial cells from cheek and lateral border of the tongue mechanically exfoliated, placed in fixative, and dropped in clean slides which were checked for the above nuclear phenotypes. The results pointed out no significant statistically differences (p > 0.05) of micronucleated oral mucosa cells before versus after X-ray exposure for both oral sites evaluated either to smokers or to non-smokers. X-ray exposure was able to increase other nuclear alterations closely related to cytotoxicity such as karrhyorexis, pyknosis, and karyolysis for two groups evaluated. Nevertheless, the most pronunciated effects were found to lateral border of the tongue of smokers. In summary, these data indicate that panoramic X-ray is able to induce cellular death in oral mucosa cells. It seems that lateral border of the tongue is more sensitive site to cytotoxic insult induced by ionizing radiation combined with continuous cigarette smoke exposure.


Asunto(s)
Mucosa Bucal/patología , Radiografía Panorámica , Fumar/patología , Lengua/patología , Adulto , Muerte Celular/efectos de la radiación , Núcleo Celular/efectos de la radiación , Daño del ADN , Exposición a Riesgos Ambientales , Células Epiteliales/patología , Células Epiteliales/efectos de la radiación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Micronúcleos con Defecto Cromosómico/clasificación , Mucosa Bucal/efectos de la radiación , Dosis de Radiación , Lengua/efectos de la radiación
14.
Radiat Med ; 26(6): 325-30, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18677605

RESUMEN

PURPOSE: Although it has been clearly demonstrated that X-rays play a key role in diagnosing medical and dental problems, this type of ionizing radiation is also able to induce noxious activities, such as genetic damage. The aim of the present study was to evaluate DNA damage (micronucleus) and cellular death in exfoliated buccal mucosa cells from healthy individuals (smokers and nonsmokers) following dental X-ray exposure. MATERIAL AND METHODS: A total of 39 healthy people who had submitted to panoramic dental radiography were included in the study: 9 smokers and 30 nonsmokers. RESULTS: The results indicated no significant statistically differences (P>0.05) in micronucleated oral mucosa cells before and after dental X-ray exposure. On the other hand, X-ray exposure did increase other nuclear alterations closely related to cytotoxicity, such as karyorrhexis, pyknosis, and karyolysis. It seems that cigarette smoke did not affect X-ray outcomes induced in buccal cells. CONCLUSION: These data indicate that dental panoramic radiography may not induce chromosomal damage, but it is able to promote cytotoxicity. Because cellular death is considered a prime mechanism in nongenotoxic mechanisms of carcinogenesis, dental X-ray should be used only when necessary.


Asunto(s)
Daño del ADN/genética , Monitoreo del Ambiente/métodos , Mucosa Bucal/citología , Mucosa Bucal/efectos de la radiación , Radiografía Panorámica/efectos adversos , Adulto , Muerte Celular , Femenino , Humanos , Masculino , Pruebas de Micronúcleos , Fumar/efectos adversos
15.
Eur J Orthod ; 30(6): 572-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19054813

RESUMEN

This study compared the effects produced by two different molar distalizers, namely cervical headgear (CHG) and the intraoral pendulum appliance, associated with fixed orthodontic appliances. The headgear group comprised 30 patients (19 females, 11 males), with an initial age of 13.07 years [standard deviation (SD) = 1.3], treated with CHG and fixed orthodontic appliances for a mean period of 3.28 years, and the pendulum group 22 patients (15 females, 7 males), with initial age of 13.75 years (SD = 1.86), treated with the pendulum appliance followed by fixed orthodontic appliances for a mean period of 4.12 years. Lateral cephalograms were taken at the start (T1) and on completion (T2) of orthodontic treatment. The pendulum and CHG groups were similar as to initial age, severity of the Class II malocclusion, gender distribution, initial cephalometric characteristics, and initial and final treatment priority index (TPI). Only treatment time was not similar between the groups, with a need for annualization for data for the pendulum group. The data were compared with independent t-tests. There was significantly greater restriction of maxillary forward growth and improvement of the skeletal maxillomandibular relationship in the CHG group (P < 0.05). The maxillary molars were more mesially tipped and extruded and the mandibular molars more uprighted in the CHG group compared with the pendulum group (P < 0.05). There was more labial tipping of the mandibular incisors and greater overbite reduction in the pendulum group. The pendulum appliance produced only dentoalveolar effects, different from the CHG appliance, which restricted maxillary forward displacement, thus improving the skeletal maxillomandibular relationship.


Asunto(s)
Aparatos de Tracción Extraoral , Maloclusión Clase II de Angle/terapia , Diseño de Aparato Ortodóncico , Ortodoncia Correctiva/métodos , Técnicas de Movimiento Dental/instrumentación , Adolescente , Cefalometría , Niño , Femenino , Humanos , Masculino , Estudios Retrospectivos , Estadísticas no Paramétricas
16.
Saudi Dent J ; 30(1): 38-42, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30166869

RESUMEN

The aim of this study was to investigate genotoxicity and cytotoxicity of some orthodontic glass ionomer cements commercially available by means of the single cell gel (comet) assay. For this purpose, five commercial orthodontic glass ionomer cements (Vidrion C®, Meron®, Optiband®, Multicure® and Ultra Band Lok®) were tested in murine fibroblasts in vitro. For this purpose, eluates from each cement were prepared according manufactures instructions at 0, 2, 4, 8, 18, 32 and 64 days of immersion in artificial saliva at 37 °C. All orthodontic glass ionomer cements failed to induce cytotoxicity to murine fibroblasts for all periods evaluated in this study. However, Vidrion C® was able to induce genotoxicity after 64 days of exposure to eluates. Meron® also demonstrated genotoxicity as depicted by increasing DNA damage on 2nd day. Multicure® demonstrated genotoxicity on 32nd day and Ultra band Lok on 18th, 32nd days of exposure. Taken together, our results demonstrated that orthodontic cements derived from resin-modified glass ionomer composite (Multicure®) and compomer (Ultra Band Lok®) cause genetic damage in mammalian cells in vitro.

17.
Anticancer Res ; 37(10): 5383-5388, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28982846

RESUMEN

Dental X-rays are widely used in clinical practice, since the technique is an important approach for diagnosing diseases in dental and periodontal tissues. However, it is widely known that radiation is capable of causing damage to cellular systems, such as genotoxicity or cytotoxicity. Thus, the aim of this review was to present a critical analysis regarding the studies published on genotoxicity and cytotoxicity induced by dental X-rays in oral mucosa cells. Such studies have revealed that some oral cell types are more sensitive than others following exposure to dental X-rays. Certainly, this review will contribute to a better understanding of this matter as well as to highlighting perspectives for further studies. Ultimately, such data will promote better safety for both patients and dental professionals.


Asunto(s)
Transformación Celular Neoplásica/efectos de la radiación , Daño del ADN , Mucosa Bucal/efectos de la radiación , Neoplasias de la Boca/etiología , Neoplasias Inducidas por Radiación/etiología , Radiografía Dental/efectos adversos , Animales , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Humanos , Mucosa Bucal/metabolismo , Mucosa Bucal/patología , Neoplasias de la Boca/genética , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Neoplasias Inducidas por Radiación/genética , Neoplasias Inducidas por Radiación/metabolismo , Neoplasias Inducidas por Radiación/patología
18.
J Vasc Access ; 18(2): 167-169, 2017 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-27911465

RESUMEN

OBJECTIVE: Describe the construction of arteriovenous fistula for hemodialysis in chronic renal patient on hemodialysis who presented chronic arterial obstruction in the upper limb. METHODS: A surgical procedure was performed on a patient with obstruction of the brachial artery in its proximal third. The procedure was carried out by the construction of a bypass with autologous vein between the proximal brachial and distal brachial arteries and the performing of an arteriovenous fistula with superficialized and anteriorized basilic vein, with anastomosis in the bypass at the same surgical procedure. RESULTS: There was good immediate result and arteriovenous fistula presented function for 43 months. CONCLUSIONS: Even when faced with chronic obstructive arterial disease in the arm, there is the possibility of creating a new arteriovenous fistula for hemodialysis.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/métodos , Arteria Braquial/cirugía , Enfermedades Renales/terapia , Enfermedad Arterial Periférica/complicaciones , Diálisis Renal , Extremidad Superior/irrigación sanguínea , Venas/cirugía , Angiografía , Arteria Braquial/diagnóstico por imagen , Arteria Braquial/fisiopatología , Enfermedad Crónica , Humanos , Enfermedades Renales/complicaciones , Enfermedades Renales/diagnóstico , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/fisiopatología , Resultado del Tratamiento , Grado de Desobstrucción Vascular , Venas/diagnóstico por imagen , Venas/fisiopatología
19.
Am J Orthod Dentofacial Orthop ; 130(4): 502-10, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17045150

RESUMEN

INTRODUCTION: The purpose of this study was to evaluate the skeletal and dental changes in patients who underwent distalization of their maxillary molars with pendulum appliances. METHODS: The sample consisted of 31 patients (initial mean age, 14.58 years) with Angle Class II molar relationships and all permanent teeth up to the second molars. The maxillary molars were distalized with pendulum appliances for a mean period of 5.87 months. Lateral cephalograms, 45 degrees oblique radiographs, and dental casts were obtained before and after distalization. Changes produced by the pendulum appliance were analyzed with paired t tests. RESULTS: Maxillary first molar distalization accounted for 63.5% of the space opening; mesial movement of the maxillary first premolars contributed 36.5% of the space. The mean space opening on lateral cephalograms was 7.25 mm, and the rate of molar movement was 1.23 mm per month. The mean distalization of the maxillary molars was 4.6 mm, with a mean distal crown tipping of 18.5 degrees The maxillary molars experienced expansion, with a smaller effect on the first molars than on the second molars. The pendulum appliance produced symmetrical expansion, with a rate of 1.04 mm per month on the right and 1.10 mm per month on the left. CONCLUSIONS: The pendulum appliance is effective for distalization of the maxillary molars and the establishment of a Class I molar relationship in a relatively short time. However, caution is needed to control collateral effects, including mesial movement of the first premolars and distal tipping of the molar crowns.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Movimiento Mesial de los Dientes/etiología , Aparatos Ortodóncicos/efectos adversos , Técnicas de Movimiento Dental/instrumentación , Adolescente , Cefalometría , Niño , Femenino , Humanos , Masculino , Maxilar , Modelos Dentales , Diente Molar/fisiopatología , Métodos de Anclaje en Ortodoncia/instrumentación , Estudios Prospectivos
20.
Am J Orthod Dentofacial Orthop ; 129(4): 520-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16627178

RESUMEN

INTRODUCTION: This prospective clinical study analyzed the distalization of maxillary molars achieved by the pendulum appliance and its effect on the anchorage teeth during and after fixed orthodontic treatment. METHODS: Lateral cephalograms of 22 adolescents (15 girls, 7 boys) taken pretreatment, after distalization, after leveling and aligning, and after fixed orthodontic treatment were evaluated. The initial mean age was 14.5 years (SD = 1.80). The mean time for distalization of the maxillary molars was 5.85 months (SD = 1.82), and the total treatment time was 3.61 years (SD = 1.83). RESULTS: The pendulum appliance moved the maxillary molars distally, but with significant distal inclination, protrusion of the anterior teeth, and increase in lower anterior facial height (LAFH) due to the clockwise mandibular rotation. After fixed orthodontic treatment, the maxillary incisors and the maxillary first premolars and first molars were returned to their pretreatment anteroposterior positions. Thus, at postdistalization, there was 2.1 mm of protrusion of the maxillary first molars, despite the anchorage reinforcement (Nance button and cervical headgear worn at night during fixed appliance therapy). However, at the end of treatment, all patients had Class I molar relationships. CONCLUSIONS: The pendulum appliance followed by fixed orthodontic treatment corrected the Class II sagittal relationship, especially due to the dentoalveolar changes secondary to the spontaneous mandibular growth in the anterior direction during fixed appliance treatment.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Maloclusión/etiología , Métodos de Anclaje en Ortodoncia , Aparatos Ortodóncicos/efectos adversos , Técnicas de Movimiento Dental/instrumentación , Adolescente , Factores de Edad , Cefalometría/estadística & datos numéricos , Contraindicaciones , Cara/anatomía & histología , Femenino , Humanos , Masculino , Maloclusión/terapia , Mandíbula/crecimiento & desarrollo , Diente Molar/fisiopatología , Retenedores Ortodóncicos , Ortodoncia Correctiva/instrumentación , Ortodoncia Correctiva/métodos , Estudios Prospectivos
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