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1.
Niger J Clin Pract ; 23(8): 1110-1119, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32788489

RESUMEN

Background: Bimaxillary protrusion is a condition wherein esthetic concerns are the main reason behind seeking orthodontic treatment. Aim: The aim of this retrospective cephalometric study was to evaluate the soft tissue profile and dental changes among female Saudi bimaxillary protrusion patients treated with extraction of all second premolars followed by retraction of the anterior teeth. Subjects and Methods: Pre and posttreatment cephalometric radiographs of adult female patients (ages 18-30 years) who underwent orthodontic therapy for Class I bimaxillary protrusion were obtained. Data were analyzed with SPSS® software. A paired t-test and Pearson's correlation coefficients were conducted with the statistical significance set at 95% (P value < 0.05). Results: At posttreatment, there was an overall decrease in the mean values among the majority of the soft tissue and dental cephalometric angles and linear measurements. Among soft tissue variables, there was a marginal increase in the upper lip length by 1.49 mm (P < 0.001), and the nasolabial angle increased markedly by 7.64° (P < 0.001). Similarly, a marked increase in retroclination by 5.95° (P < 0.001) was observed among the dental variables. Conversely, no significant changes were noted in the lower incisors. Pearson's correlation analysis revealed a significant correlation between all the different dental variables. Within the soft tissue variables, there was a significant positive correlation between changes in the upper lip protrusion, lower lip protrusion, upper lip thickness, and the distance from the upper and lower lips to the S-line.


Asunto(s)
Diente Premolar/cirugía , Incisivo , Labio , Maloclusión/terapia , Adolescente , Adulto , Cefalometría/estadística & datos numéricos , Estética , Femenino , Humanos , Incisivo/patología , Labio/anatomía & histología , Labio/patología , Masculino , Ortodoncia Correctiva/métodos , Radiografía , Estudios Retrospectivos , Extracción Dental , Resultado del Tratamiento , Adulto Joven
2.
Oral Dis ; 26(2): 457-464, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31742839

RESUMEN

OBJECTIVE: To describe oral alterations in children with congenital Zika syndrome (CZS). METHODS: This was a case series, whose research instrument was a structured questionnaire, associated with the use of medical record data and extra and intraoral clinical examination. RESULTS: Thirty-two children were evaluated, the majority male (18/32%-56.3%), mean age 22 months (SD = 2.71). It was also observed that the majority of the patients (19/32%-59.4%) presented a low family income. All the children had a mean head circumference of 29.43 cm (SD = 1.42). Regarding the alterations, an ogival-shaped palate was observed in 14 children (43.7%), and delayed chronology of eruption was observed in 15 children (46.9%), of whom 7 children (21.9%) did not present eruption of the upper left lateral incisor (p = .0002) and upper right lateral incisor (p = .002) until the moment of analysis. Additionally, 03 children with yellowish dental pigmentation were identified in erupted teeth after the onset of phenobarbital use. Enamel hypoplasia was identified in 9 children (28.1%) and only one child with ankyloglossia. CONCLUSION: CZS may present delayed chronology of eruption, ankyloglossia, ogival-shaped palate, and enamel hypoplasia, requiring dental follow-up aimed at prevention, promotion, and rehabilitation of the health of these children.


Asunto(s)
Hipoplasia del Esmalte Dental/virología , Anomalías Dentarias/virología , Erupción Dental , Infección por el Virus Zika/complicaciones , Humanos , Incisivo/patología , Lactante , Masculino , Virus Zika
3.
Vet Rec ; 185(23): 730, 2019 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-31601733

RESUMEN

The progression of equine odontoclastic tooth resorption and hypercementosis (EOTRH) has not been completely evaluated, and currently, the only effective treatment is extraction of severely affected teeth. We aim to describe how the disease relates to the history and clinical findings and to report on the outcome in individual horses. This case series comprises data collected from 20 horses (age 14-29 years old) with radiographic findings of EOTRH in their incisor and/or canine teeth. Most horses affected with EOTRH in this study were admitted for dental problems, but some for other complaints such as colic. Of the 288 teeth evaluated radiographically, 224 teeth were abnormal. Radiographic findings were most frequently located in the apical aspect and reserve crown of the teeth, and lesions were also commonly found in clinically normal teeth. Histopathology of extracted teeth showed inflammation in the periodontal ligament and revealed that resorption often extended to the dentine. Some owners were unwilling to allow extraction of their horses' severely affected teeth, even though this treatment has been shown to increase the wellbeing of the horse. As EORTH is a life-long condition, the progression of the disease has to be continuously monitored and the treatments adjusted accordingly.


Asunto(s)
Enfermedades de los Caballos/patología , Hipercementosis/veterinaria , Resorción Dentaria/veterinaria , Animales , Diente Canino/diagnóstico por imagen , Diente Canino/patología , Enfermedades de los Caballos/diagnóstico por imagen , Enfermedades de los Caballos/cirugía , Caballos , Hipercementosis/patología , Hipercementosis/cirugía , Incisivo/diagnóstico por imagen , Incisivo/patología , Ligamento Periodontal , Radiografía Dental/veterinaria , Extracción Dental/veterinaria , Resorción Dentaria/patología , Resorción Dentaria/cirugía , Resultado del Tratamiento
4.
Cells ; 8(10)2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-31569682

RESUMEN

Poly(ADP-ribose) polymerase (Parp)-1 catalyzes polyADP-ribosylation using NAD+ and is involved in the DNA damage response, genome stability, and transcription. In this study, we demonstrated that aged Parp-1-/- mouse incisors showed more frequent dental dysplasia in both ICR/129Sv mixed background and C57BL/6 strain compared to aged Parp-1+/+ incisors, suggesting that Parp-1 deficiency could be involved in development of dental dysplasia at an advanced age. Computed tomography images confirmed that dental dysplasia was observed at significantly higher incidences in Parp-1-/- mice. The relative calcification levels of Parp-1-/- incisors were higher in both enamel and dentin (p < 0.05). Immunohistochemical analysis revealed (1) Parp-1 positivity in ameloblasts and odontoblasts in Parp-1+/+ incisor, (2) weaker dentin sialoprotein positivity in dentin of Parp-1-/- incisor, and (3) bone sialoprotein positivity in dentin of Parp-1-/- incisor, suggesting ectopic osteogenic formation in dentin of Parp-1-/- incisor. These results indicate that Parp-1 deficiency promotes odontogenic failure in incisors at an advanced age. Parp-1 deficiency did not affect dentinogenesis during the development of mice, suggesting that Parp-1 is not essential in dentinogenesis during development but is possibly involved in the regulation of continuous dentinogenesis in the incisors at an advanced age.


Asunto(s)
Pulpa Dental/patología , Displasia de la Dentina/etiología , Regulación del Desarrollo de la Expresión Génica , Incisivo/patología , Odontoblastos/patología , Odontogénesis , Poli(ADP-Ribosa) Polimerasa-1/fisiología , Factores de Edad , Animales , Pulpa Dental/metabolismo , Displasia de la Dentina/patología , Femenino , Incisivo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , Odontoblastos/metabolismo
5.
Medicine (Baltimore) ; 98(40): e17356, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31577730

RESUMEN

Molar-incisor malformation (MIM) is a recently defined dental abnormality of molar root and incisors, and introduced as one of the causes of periapical and periodontal abscess. The purpose of this study was to investigate the clinical and radiological features of MIM, with special emphasis on various medical history. A total of 38 patients with MIM were included in this study. Radiographic features and clinical data, including medical history, chief complaint, associated complications, treatment, and prognosis, were retrospectively investigated. On radiographs, the affected molars showed short, slender, underdeveloped roots and constricted pulp chambers. All affected incisors and canines exhibited dilacerated short roots, wedge-shaped defect on the cervical part of the crown. Complications included periodontal bone loss (52.6%), endodontic lesion (50.0%), and endodontic-periodontal lesion (28.9%). The medical histories of the patients with MIM indicate that almost all (94.7%) were hospitalized due to problems during the neonatal period. MIM may cause various dental problems, such as periapical and periodontal abscess and early loss of the affected teeth. The early diagnosis of MIM on radiographs and appropriate treatment will contribute to a favorable prognosis, especially for young and adolescent patients.


Asunto(s)
Incisivo/diagnóstico por imagen , Incisivo/patología , Diente Molar/diagnóstico por imagen , Diente Molar/patología , Anomalías Dentarias/diagnóstico por imagen , Anomalías Dentarias/patología , Adolescente , Pérdida de Hueso Alveolar/etiología , Niño , Preescolar , Cavidad Pulpar/diagnóstico por imagen , Cavidad Pulpar/patología , Femenino , Humanos , Masculino , Radiografía Dental , Estudios Retrospectivos , Anomalías Dentarias/complicaciones , Anomalías Dentarias/diagnóstico , Raíz del Diente/diagnóstico por imagen , Raíz del Diente/patología , Adulto Joven
6.
Homo ; 70(3): 185-192, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31486821

RESUMEN

The aim was to analyze the changes in mandibular dental arch shape during adolescence and assess its relation to late mandibular incisor crowding. Longitudinal study included 68 orthodontically untreated subjects (49% female) and analyzed their data for the ages of 12, 15, 18 and 21 years. Measurements included anterior arch depth, intercanine, interpremolar/anterior and intermolar/posterior width, Little's Irregularity and Bolton's index and the ratio between anterior arch depth and width. Males had significantly greater posterior widths than females at any age (p < 0.05). The anterior arch depth continuously decreased (p < 0.05), while width increased after the age of 18 years. Mandibular incisor crowding increased during all investigated periods (p < 0.05). The increase of intercanine width at 12-21 years of age reduced the risk for mandibular incisor crowding in the same period by 74% (OR: 0.265: 95% CI 0.076-0.931; p = 0.045). The shape of mandibular dental arch continues to change during adolescence becoming more squared while mandibular incisor crowding increases. The increase in mandibular intercanine width reduces the risk of crowding.


Asunto(s)
Arco Dental , Incisivo , Maloclusión/patología , Adolescente , Adulto , Antropología Física , Niño , Arco Dental/anatomía & histología , Arco Dental/crecimiento & desarrollo , Arco Dental/patología , Femenino , Humanos , Incisivo/anatomía & histología , Incisivo/patología , Estudios Longitudinales , Masculino , Odontometría , Adulto Joven
7.
Homo ; 70(2): 147-154, 2019 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-31486824

RESUMEN

The aim of this study was to compare the prevalence of anatomical variants of maxillary lateral incisors in archaeological and modern populations from the Maya region. Both populations were derived from the state of Yucatan, Mexico. The archaeological sample consisted of human remains representing 122 individuals from the ancient Maya archaeological site of Xcambo (AD 250-700). The modern sample consisted of 475 dental models from the municipality of Tahdziú, Yucatan. The anatomical variants evaluated included microdontia, barrel-shaped incisors, and talon cusp. The prevalence of each anatomical variant for each population was calculated and compared (Fisher p < 0.05). The prevalence of anatomical variants was 15.57% (n = 19) in the archaeological sample and 14.11% (n = 67) in the modern one; the difference was not significant (p = 0.666). When compared by specific anatomical variants, a significant (p = 0.013) association was observed for microdontia: 2.45% (n = 3) in the archaeological population and 9.05% (n = 43) in the modern population. Barrel-shaped incisors (p = 0.522) and talon cusp (p = 0.466) did not exhibit significant associations. The overall prevalence of anatomical variants in the maxillary lateral incisors in this region has not changed. The prevalence of microdontia has increased over the last 1500 years, and different microevolutionary processes may be called into question for such change.


Asunto(s)
Incisivo/anatomía & histología , Incisivo/patología , Maxilar/anatomía & histología , Anomalías Dentarias/patología , Arqueología , Historia Antigua , Historia Medieval , Humanos , México , Paleodontología , Anomalías Dentarias/historia
8.
Medicina (Kaunas) ; 55(9)2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-31484416

RESUMEN

Background and objectives: This study investigated the morphology of the labial and palatal bony wall of the maxillary central and lateral incisors using cone-beam computed tomography (CBCT). The difference between males and females and the measurement between right and left sides were measured. Materials and Methods: Twenty participants, consisting of 11 females and 9 males having normal occlusion, were used for the analysis. The mean age was 21.9 ± 3.0 years. The thickness of the labial bony wall and palatal bony wall, perpendicular to the long axis of the root, were evaluated at 3 and 5 mm apical from the cemento-enamel junction (CEJ) and at the root apex. The available bony wall below the apex of the central and lateral incisors, and the angulation between the long axis of the tested tooth and outer surface of the labial bone were measured. Results: The mean labial bony wall thickness at the 3 and 5 mm apical from the CEJ were 1.1 ± 0.3 mm and 1.0 ± 0.4 mm for central incisors, respectively, as well as 1.2 ± 0.4 mm and 1.0 ± 0.4 mm for lateral incisors, respectively. The mean palatal bony wall thickness at 5 mm from the CEJ was above 2 mm in the central and lateral incisors. The percentage of labial bony wall thickness 2 mm or greater at the root apex in central incisors was higher than in lateral incisors (62.5% vs. 55.0%). The percentage of palatal bony wall thickness ≥2 mm at 3 mm apical from the CEJ in the central incisors was higher than in the lateral incisors (37.5% vs. 15.0%). The results on the left and right sides did not show statistically significant differences, except in the labial and palatal bony wall thickness at 3 mm from the CEJ in the lateral incisor. Generally, no significant differences were seen between males and females, but males had a significantly higher labial bony wall thickness at 3 and 5 mm from the CEJ in the central and lateral incisors when compared with females. Conclusions: This study showed that a majority of the cases of Korean participants had less than 2 mm of labial bony wall thickness at 3 and 5 mm apical from the CEJ at central and lateral incisors, and this should be kept in mind while performing dental practices, including tooth extraction or immediate implantation in anterior regions. Preoperative analysis using CBCT may be beneficial for establishing the treatment plan.


Asunto(s)
Pérdida de Hueso Alveolar/clasificación , Oclusión Dental , Incisivo/patología , Adolescente , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Masculino , Maxilar/patología , Adulto Joven
9.
Braz Oral Res ; 33: e048, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31432924

RESUMEN

This cross-sectional study aimed to assess the prevalence of molar incisor hypomineralization (MIH) and its relationship with the number of primary teeth with developmental defects of enamel (DDE). A representative population-based sample of 731 schoolchildren was randomly selected from the public school system in Curitiba, Brazil. Schoolchildren aged 8 years with fully erupted permanent first molars and incisors were eligible for the study. MIH and DDE were classified by four calibrated examiners (kappa > 0.75) according to EAPD criteria and to the FDI-modified DDE index. Clinical data were collected in a school environment. Socioeconomic information was collected through a self-administered semistructured questionnaire applied to the children's caregivers. Statistical analyses were carried out using Poisson multiple regression with robust variance (α = 0.05). MIH prevalence was 12.1% (95%CI: 10-15), and opacities were the most prevalent defect. Socioeconomic factors were not associated with MIH. Children with demarcated opacity in primary teeth presented a higher prevalence of MIH than those without DDE in primary teeth. In the multiple analysis, the increase of one primary tooth affected by demarcated opacity increased the prevalence of MIH by 33% (PR = 1.33, 95%CI: 1.15-1.53, p < 0.001). Asian children had a higher prevalence of MIH (PR = 2.91, 95%CI: 1.08-8.09 p = 0.035) than did Caucasian children.Conclusion: Based on these findings, the prevalence of MIH in Curitiba was 12.1%. Demarcated opacity in primary teeth could be considered a predictor of MIH.


Asunto(s)
Hipoplasia del Esmalte Dental/epidemiología , Diente Primario , Brasil/epidemiología , Niño , Estudios Transversales , Hipoplasia del Esmalte Dental/patología , Femenino , Humanos , Incisivo/patología , Masculino , Diente Molar/patología , Prevalencia , Análisis de Regresión , Factores de Riesgo , Autoinforme , Índice de Severidad de la Enfermedad , Factores Socioeconómicos , Diente Primario/patología
11.
Am J Orthod Dentofacial Orthop ; 156(2): 210-219, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31375231

RESUMEN

INTRODUCTION: More patients are choosing customized orthodontic appliances because of their excellent esthetics. It is essential that clinicians understand the biomechanics of the tooth movement tendency in customized lingual orthodontics. This study aimed to evaluate the tooth movement tendency during space closure in maxillary anterior teeth with the use of miniscrew anchorage in customized lingual orthodontics with various power arm locations. METHODS: Three-dimensional finite element models of the maxilla were created with miniscrews and power arms; the positions were varied to change the force directions. A retraction force (1.5 N) was applied from the top of the miniscrews to the selected points on the power arm, and the initial displacements of the reference nodes of the maxillary teeth were analyzed. RESULTS: After applying force in different directions, power arms located at the distal side of the canines led to larger initial lingual crown tipping and occlusal crown extrusion of the maxillary incisors compared with power arms located at the midpoint between the lateral incisors and canines, and caused a decreasing trend of the intercanine width. CONCLUSIONS: In customized lingual orthodontic treatment, power arms located at the distal side of the canines are unfavorable for anterior teeth torque control and intercanine width control. Power arms located at the midpoint between the lateral incisors and canines can get better torque control, but still cannot achieve excepted torque without extra torque control methods, no matter whether its force application point is higher than, lower than, or equal to the level of the top of the miniscrews.


Asunto(s)
Tornillos Óseos , Análisis de Elementos Finitos , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Cierre del Espacio Ortodóncico , Técnicas de Movimiento Dental/instrumentación , Técnicas de Movimiento Dental/métodos , Adulto , Fenómenos Biomecánicos , Simulación por Computador , Diente Canino/patología , Humanos , Imagenología Tridimensional/métodos , Incisivo/patología , Maxilar , Modelos Biológicos , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos , Soportes Ortodóncicos , Cierre del Espacio Ortodóncico/instrumentación , Cierre del Espacio Ortodóncico/métodos , Alambres para Ortodoncia , Planificación de Atención al Paciente , Estrés Mecánico , Corona del Diente , Torque , Resultado del Tratamiento
12.
Am J Orthod Dentofacial Orthop ; 156(2): 248-256.e2, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31375235

RESUMEN

INTRODUCTION: The treatment options for adults with increased overbite are limited to dentoalveolar changes that camouflage the condition. Because of high relapse tendency, defining the problem area is important when creating a treatment plan. This study aimed to evaluate dentoskeletal morphology in skeletal Class I and II anomalies associated with Angle Class I, Class II Division 1 (Class II/1), and Class II Division 2 (Class II/2) malocclusions with increased overbite compared with normal occlusion. METHODS: Pretreatment cephalograms of 306 patients (131 men, 175 women; overall ages 18-45 years) were evaluated. Four groups were constructed. Three groups had increased overbite (>4.5 mm): group 1 (n = 96) skeletal Class I (ANB = 0.5°-4°), group 2 (n = 85) skeletal Class II (ANB >4.5°) with Class II/1; and group 3 (n = 79) skeletal Class II with Class II/2 malocclusion. Group 4 as a control (n = 46) skeletal Class I normal overbite. Dental and skeletal characteristics of the groups were compared by sex. For statistical evaluations, analysis of variance followed by Tukey post hoc, Mann-Whitney U, and Kruskall-Wallis tests were used. Additionally correlation coefficients between overbite and skeletal/dental parameters were calculated. RESULTS: Between sexes, with regard to skeletal parameters, the men had greater values in millimetric measurements, and the women had higher SN/GoGn values. Maxillary/mandibular molar heights and the mandibular incisor heights were higher in men. In group 1, decreased lower anterior facial height (LAFH), retrusive mandibular incisors, and increased interincisal degree were determined. The maxillary molars were intrusive, whereas the vertical position of the mandibular molars and incisors in both jaws were normal. In group 2, retrognathic mandible, increased LAFH and mandibular plane angle, extrusive maxillary/mandibular incisors, protrusive mandibular incisors, and decreased interincisal degree were found. In group 3, decreased LAFH, increased interincisal degree, and retrusive incisors in both jaws were determined. There were significant negative correlations between SN/GoGN, palatal plane, and overbite in group 2 and between ANS-SN and overbite in group 3, and positive correlation between interinsical angle and overbite in all increased overbite groups. CONCLUSIONS: Dental morphology seems to be the main factor of increased overbite. Differences between groups were related primarily to inclinations and vertical positions of the incisors, rather than molar positions.


Asunto(s)
Maloclusión de Angle Clase II/patología , Maloclusión de Angle Clase I/patología , Sobremordida/epidemiología , Sobremordida/patología , Adolescente , Adulto , Análisis de Varianza , Puntos Anatómicos de Referencia , Cefalometría , Femenino , Humanos , Incisivo/patología , Masculino , Maloclusión de Angle Clase III/patología , Mandíbula/patología , Maxilar/patología , Persona de Mediana Edad , Diente Molar/patología , Retrognatismo/patología , Factores Sexuales , Turquia , Adulto Joven
13.
Biomed Res Int ; 2019: 4934128, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31317031

RESUMEN

Introduction: With an increasing demand for orthodontic treatment for adult patients, orthodontic professionals are constantly seeking novel strategies and technologies that can accelerate tooth movement in order to shorten the treatment period. For instance, in recent years, the influences of different surgical techniques on orthodontic tooth movement in the ipsilateral side of surgery were intensively investigated. Here, we attempt to examine if corticotomy could also affect the rate of tooth movement in the contralateral side of the surgery by using a rodent model. Materials and Methods: 72 eight-week-old Sprague-Dawley rats were randomly divided into three groups as follows: the Control group (orthodontic treatment devices delivered only, no tooth movement), the orthodontic tooth movement (OTM) group (orthodontic treatment devices delivered and orthodontic treatment performed), and the Corticotomy + OTM group (remote corticotomy performed, orthodontic treatment devices delivered, followed by orthodontic treatment). The surgical procedure was conducted on the right side of the maxilla at the time of appliance placement and a force of 60 g was applied between the maxillary left first molar and maxillary incisors using nickel-titanium springs to stimulate OTM. The OTM distance and speed were tracked at 3, 7, 14, and 28 days post-surgery, followed by histological and immunohistochemical assessments. Results: In comparison with orthodontic treatment only, the contralateral corticotomy significantly accelerated OTM. Furthermore, animals undergoing corticotomy + OTM presented with a greater number of osteoclasts on the compression side, stronger staining of the osteogenic marker on the tension side, and higher expression of an inflammatory marker than the OTM group animals. Conclusion: Our current study demonstrates that remote corticotomy effectively accelerates alveolar bone remodeling and OTM. The study enriches our understanding of the regional acceleratory phenomenon (RAP) and offers an alternative strategy for accelerating OTM to shorten the orthodontic treatment period.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Resorción Ósea/cirugía , Incisivo/cirugía , Osteogénesis/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Humanos , Incisivo/crecimiento & desarrollo , Incisivo/patología , Maxilar/crecimiento & desarrollo , Maxilar/patología , Maxilar/cirugía , Diente Molar/crecimiento & desarrollo , Diente Molar/patología , Diente Molar/cirugía , Níquel/uso terapéutico , Alambres para Ortodoncia , Osteoclastos/metabolismo , Osteoclastos/patología , Ratas , Titanio/uso terapéutico , Técnicas de Movimiento Dental
14.
Am J Orthod Dentofacial Orthop ; 156(1): 137-147, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31256827

RESUMEN

A 16-year-old patient sought orthodontic correction for profile improvement and labially inclined maxillary incisors. She had Class II malocclusion, protrusive maxillary and mandibular incisors, and increased overjet and overbite with an American Board of Orthodontics discrepancy index value of 25. She was treated with maxillary premolar extractions and miniscrew-supported en masse retraction assisted with piezoincisions. Extraction spaces (7.5 mm per side) were closed with maximum anchorage in 10 months. Total treatment time was 23 months. Twenty-seven months after debonding, a pink spot was noted at the buccocervial region of the left central incisor. Radiographic evaluation on cone-beam computed tomographic scans revealed a severe case of invasive cervical resorption on both central incisors, around which the piezosurgical cuts had been made. Treatment proceeded with a nonintervention approach and the affected teeth were reinforced with a lingual retainer.


Asunto(s)
Maloclusión de Angle Clase II/terapia , Ortodoncia Correctiva/métodos , Sobremordida/terapia , Piezocirugía/efectos adversos , Adolescente , Diente Premolar/cirugía , Tornillos Óseos , Cefalometría , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Incisivo/diagnóstico por imagen , Incisivo/patología , Incisivo/cirugía , Maloclusión de Angle Clase II/diagnóstico por imagen , Maloclusión de Angle Clase II/cirugía , Mandíbula , Maxilar/diagnóstico por imagen , Maxilar/patología , Maxilar/cirugía , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos , Soportes Ortodóncicos , Alambres para Ortodoncia , Sobremordida/diagnóstico por imagen , Sobremordida/cirugía , Radiografía Panorámica , Resorción Radicular/etiología , Técnicas de Movimiento Dental/métodos , Resultado del Tratamiento , Dimensión Vertical
15.
Acta Odontol Latinoam ; 32(1): 44-48, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31206574

RESUMEN

Clinically, Molar-Incisor Hypomineralization (MIH) lesions are not distributed symmetrically, and their severity varies even within the same arcade. AIM: To estimate the frequency of asymmetries in hypomineralized lesions on permanent molars and incisors of children with MIH. METHODS: Three pediatric dentists, calibrated following the diagnostic criteria of Mathu-Muju and Wright (2006) (Kappa 0.87) identified presence and severity of opacities on molars and incisors of patients with MIH. Six pairs of teeth (permanent maxillary and mandibular first molars, central and lateral incisors) were evaluated in each patient. Degree of lesion severity (0-none, 1-mild, 2-moderate, 3-severe) was recorded for each tooth. For each pair containing any affected teeth, asymmetry of presence (one tooth in the pair with lesion and the other intact), asymmetry of severity (both teeth with lesions but with different degrees of severity) or symmetry of severity (both affected teeth with the same degree of severity) were evaluated. The recorded values were entered into a database to calculate percentages, 95% confidence intervals and Chi-Square test for comparisons. RESULTS: The sample consisted of475 of the 1032 pairs of teeth evaluated in the 172 patients included in the study, mean age 11±2.2 years, and 50% female. Asymmetry was found for 67.5% (63.1 - 71.7) of the pairs of the studied teeth. There was a significant relationship between asymmetries and symmetries (p=0.038). A total 50.1% of the pairs were asymmetrical for presence of opacities. Of these, 62.2% scored severity 1 (mild). Symmetry of severity was found for 32.5% of the lesions. Among the pairs of affected teeth, the most frequently observed degrees of lesion severity were mild and moderate, with the exception of lower molars, in which 49% had severe lesions. CONCLUSIONS: In this study, MIH lesions were asymmetrical both in presence and severity for all tooth types.


Asunto(s)
Hipoplasia del Esmalte Dental/epidemiología , Incisivo/patología , Maxilar/patología , Diente Molar/patología , Desmineralización Dental/epidemiología , Adolescente , Argentina/epidemiología , Niño , Hipoplasia del Esmalte Dental/clasificación , Femenino , Humanos , Masculino , Prevalencia , Índice de Severidad de la Enfermedad , Desmineralización Dental/clasificación
16.
J Forensic Odontostomatol ; 37(1): 51-62, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31187743

RESUMEN

Dental forensics for the resolution of unnatural death remains an underdeveloped field. Accordingly, an experimental study was conducted with six to seven months old Wistar rats that were drowned in order to identify key postmortem features and pattern of dental decomposition. The visual, structural and elemental changes were assessed periodically. Based on mode of death, they were designated as SB (euthanized and soil buried), FWD (fresh water drowned) and SWD (sea water drowned). Postmortem features as well as the structural and elemental patterns of decomposition of teeth were analyzed with Field Emission Scanning Electron Microscopy (FE-SEM) and Energy Dispersive Spectroscopy (EDAX) periodically for two months. The periodic observation of elemental changes in the teeth of SB, FWD and SWD rats allowed us to derive an equation using linear regression analysis to relate the degree of dental decomposition with the time since death. The difference in pattern of surface deterioration was also observed. The present findings could provide a better knowledge in resolving unnatural deaths and supporting evidence for legal prosecution.


Asunto(s)
Ahogamiento/patología , Incisivo/patología , Cambios Post Mortem , Animales , Entierro , Odontología Forense/métodos , Agua Dulce , Modelos Lineales , Microscopía Electrónica de Rastreo , Modelos Animales , Proyectos Piloto , Ratas Wistar , Agua de Mar , Espectrometría por Rayos X
17.
J Mech Behav Biomed Mater ; 97: 330-338, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31153114

RESUMEN

OBJECTIVES: To determine the effect of heat on flexural strength (FS), maximum strain (MS), storage modulus (SM), tan delta (TD) and chemical changes through micro-Raman spectroscopy of dentine exposed to 2.5% NaOCl or saline. METHOD: ology: Dentine bars were randomly allocated to 8 test groups. Half (groups 2,4,6,8) were treated with NaOCl for 20 min; the rest (groups 1,3,5,7) remained in saline. FS/MS were measured in groups 1-4 (n = 15) (3/4 were also heated to 200 °C & re-hydrated in saline). Micro-Raman spectroscopy was performed on bars from groups 1-4. SM/TD were measured in 5-8: in 5/6 (n = 10), repeated after heating (200 °C), then following re-hydration; in 7/8 (n = 3) after heating to 25-185 °C. RESULTS: Increase in MS on heat and FS/MS on heat + NaOCl was not significant (P > 0.05). SM increased (P = 0.06) after heat treatment but reduced to initial state after rehydration (P = 0.03). TD did not change (P = 0.4) after heat (200 °C) treatment but rehydration increased it compared with pre-treatment state (P = 0.001). For dentine bars pre-treated with NaOCl, SM did not change (P = 0.6) after heat (200 °C) treatment or rehydration but TD significantly increased (P = 0.02) upon re-hydration compared with pre- (P=0.007), or post- (P = 0.03) heat-treatment states. SM and TD varied between 25-185 °C with no consistent trend amongst the NaOCl pre-treated bars. Micro-Raman only detected chemical changes following NaOCl treatment in the mineral phase. CONCLUSIONS: Exposure of dentine bars to heat and NaOCl produced only moderate changes to quasi-static but marked changes to viscoelastic properties, which may be explained by chemical alterations.


Asunto(s)
Carbonatos/química , Dentina/química , Calor , Hipoclorito de Sodio/farmacología , Diente Canino/efectos de los fármacos , Diente Canino/patología , Elasticidad , Humanos , Incisivo/efectos de los fármacos , Incisivo/patología , Diente Molar/efectos de los fármacos , Diente Molar/patología , Espectrometría Raman , Estrés Mecánico , Viscosidad
18.
Int. j. morphol ; 37(2): 522-532, June 2019. graf
Artículo en Inglés | LILACS | ID: biblio-1002254

RESUMEN

Amelogenin is one of the enamel matrices secreted by ameloblasts. A mutation of the amelogenin gene can cause hereditary dental enamel defects known as amelogenesis imperfecta (AI). Since lysosome-associated membrane protein-1 (LAMP-1), -3 (LAMP-3), and 78kDa glucose-related protein (Grp78) were identified as binding proteins of amelogenin, several studies have suggested the involvement of these binding proteins with the cell kinetics of ameloblasts in normal or abnormal conditions. The purpose of this study is to investigate the distribution of these amelogenin binding proteins in the ameloblast cell differentiation of mice with a point mutation of the amelogenin gene (Amelx*). The incisors of Amelx* mice had a white opaque color and the tooth surface was observed to be rough under a scanning electron microscope. Among the sequential ameloblast cell differentiation in the Amelx* mice, the shape of ameloblasts at the transition stage was irregular in comparison to those in wild-type (WT) mice. Immunostaining of Grp78 revealed that the whole cytoplasm of the transition stage ameloblasts was immunopositive for Grp78 antibody, while only the distal part of cell was positive in the WT mice. Furthermore, in the Amelx* mice, the cytoplasm of the transition stage ameloblasts was immunopositive for LAMP-1 and LAMP-3. These results suggest that Amelx* may cause the abnormal distribution of amelogenin binding proteins in the cytoplasm of ameloblasts.


La amelogenina es una de las matrices de esmalte secretadas por los ameloblastos. Una mutación del gen de amelogenina puede causar defectos hereditarios del esmalte dental conocidos como amelogénesis imperfecta (AI). Dado que la proteína de membrana asociada a lisosoma-1 (LAMP-1), -3 (LAMP-3) y la proteína relacionada con la glucosa de 78 kDa (Grp78) se identificaron como proteína de unión a amelogenina, varios estudios han sugerido la participación de estas proteínas con la cinética celular de los ameloblastos en condiciones normales o anormales. El objetivo del estudio fue investigar la distribución de LAMP-1, LAM-3 y Grp78 durante la diferenciación celular de ameloblastos de ratones con una mutación puntual del gen de amelogenina (Amelx*). Los incisivos de los ratones Amelx* presentaron un color blanco opaco y se observó en microscopio electrónico de barrido que la superficie del diente era áspera. La diferenciación celular secuencial y la forma de los ameloblastos en la etapa de transición en los ratones Amelx* fue irregular en comparación con los ratones silvestres (RS). La inmunotinción de Grp78 reveló que todo el citoplasma de los ameloblastos en etapa de transición fue inmunopositivo para el anticuerpo Grp78, mientras que solo la parte distal de la célula fue positiva en los ratones RS. Además, en ratones Amelx*, el citoplasma de los ameloblastos en etapa de transición fue inmunopositivo para LAMP-1 y LAMP-3. Estos resultados sugieren que Amelx* puede causar distribución anormal de proteínas de unión a amelogenina en el citoplasma de los ameloblastos.


Asunto(s)
Animales , Ratones , Glicoproteínas de la Membrana Asociadas a los Lisosomas/metabolismo , Amelogenina/metabolismo , Amelogénesis Imperfecta , Proteínas de Choque Térmico/metabolismo , Microscopía Electrónica de Rastreo , Técnica del Anticuerpo Fluorescente , Esmalte Dental/patología , Proteína 1 de la Membrana Asociada a los Lisosomas/metabolismo , Amelogenina/genética , Proteína 3 de la Membrana Asociada a Lisosoma/metabolismo , Incisivo/patología
19.
Ortodoncia ; 82(164-165): 10-14, jun. 2019. ilus
Artículo en Español | LILACS, BINACIS | ID: biblio-1024520

RESUMEN

La ubicación en la arcada de un incisivo superior ectópico y con diagnóstico de dilaceración, sin duda, es un gran desafío. Ya sea por su alto compromiso estético, así como también, por las maniobras biomecánicas a aplicar. La alteración de forma y ubicación ectópica del incisivo central superior, puede estar dada por un desarrollo anormal de dicha pieza sin causa aparente en el mayor porcentaje de los casos; aunque por causas obstructivas, como la presencia de diferentes patologías: quistes, odontomas, dientes supernumerarios; así como también, en un porcentaje menor, por traumatismos en los dientes temporarios


Asunto(s)
Niño , Erupción Ectópica de Dientes , Diente Impactado , Incisivo/patología , Incisivo/diagnóstico por imagen , Maloclusión de Angle Clase II , Maxilar
20.
PLoS One ; 14(4): e0215370, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30978248

RESUMEN

Alterations in the structure and mechanical properties of teeth in adult Wistar rats exposed to cadmium were investigated. Analyses were conducted on two sets of incisors from female and male specimens, that were intoxicated with cadmium (n = 12) or belonged to the control (n = 12). The cadmium group was administered with CdCl2 dissolved in drinking water with a dose of 4mg/kgbw for 10 weeks. The oral intake of cadmium by adult rats led to the range of structural changes in enamel morphology and its mechanical features. A significant increase of cadmium levels in the teeth in comparison to the control, a slight shift in the colour and reduction of pigmented enamel length, higher surface irregularity, a decrease of hydroxyapatite crystals size in the c-axis and simultaneous increase in pigmented enamel hardness were observed. The extent of these changes was sex-dependent and was more pronounced in males.


Asunto(s)
Cadmio/toxicidad , Incisivo/efectos de los fármacos , Animales , Fenómenos Biomecánicos , Cadmio/administración & dosificación , Cadmio/farmacocinética , Cristalización , Esmalte Dental/efectos de los fármacos , Esmalte Dental/patología , Esmalte Dental/fisiopatología , Durapatita/química , Durapatita/metabolismo , Femenino , Dureza/efectos de los fármacos , Incisivo/patología , Incisivo/fisiopatología , Masculino , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Minerales/metabolismo , Ratas , Ratas Wistar , Difracción de Rayos X
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