983 resultados para Mandibular incisors


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Introduction: The aim of this prospective clinical study was to investigate the cephalometric changes produced by bonded spurs associated with high-pull chincup therapy in children with Angle Class I malocclusion and anterior open bite. Methods: Thirty patients with an initial mean age of 8.14 years and a mean anterior open bite of -3.93 mm were treated with bonded spurs associated with chincup therapy for 12 months. An untreated control group of 30 subjects with an initial mean age of 8.36 years and a mean anterior open bite of -3.93 mm and the same malocclusion was followed for 12 months for comparison. Student t tests were used for intergroup comparisons. Results: The treated group demonstrated a significantly greater decrease of the gonial angle, and increase in overbite, palatal tipping of the maxillary incisors, and vertical dentoalveolar development of the maxillary and mandibular incisors compared with the control group. Conclusions: The association of bonded spurs with high-pull chincup therapy was efficient for the correction of the open bite in 86.7% of the patients, with a 5.23-mm (SD, +/- 1.69) overbite increase. (Am J Orthod Dentofacial Orthop 2012;142:487-93)

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Objective. The objective of this study was to investigate the prevalence of dental anomalies in individuals with Richieri-Costa-Pereira syndrome. Study Design. A total of 13 individuals with Richieri-Costa-Pereira syndrome who were older than 8 years with at least 1 available panoramic radiograph were assessed. Dental anomalies were evaluated clinically and radiographically and classified as hyperplastic, hypoplastic, or heterotopic and as alterations of shape, number, position, and structure. Enamel alterations were classified by the DDE index. Results. All individuals exhibited anomalies, with predominance of hypoplastic disorders, mainly agenesis of mandibular incisors and second premolars and demarcated creamy-white enamel opacities primarily affecting the maxillary premolars. Conclusions. Individuals with Richieri-Costa Pereira syndrome exhibit high prevalence of tooth agenesis, especially mandibular incisors and premolars, as well as high frequency of enamel opacities. These findings are compatible with the mandibular cleft observed in all individuals and also reflect the hypoplastic characteristic of the syndrome. (Oral Surg Oral Med Oral Pathol Oral Radiol 2012;114:99-106)

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Scanning electron microscopy (SEM) can be used to analyze the presence of debris and smear layer on the internal walls of root canal. This study evaluated the debris and smear removal in flattened root canals using SEM after use of different irrigant agitation protocols. Fifty mandibular incisors were distributed into five groups (n = 10) according to the irrigant agitation protocol used during chemomechanical preparation: conventional syringe irrigation with NaviTip needle (no activation), active scrubbing of irrigant with brush-covered NaviTip FX needle, manual dynamic irrigation, continuous passive ultrasonic irrigation, and apical negative pressure irrigation (EndoVac system). Canals were irrigated with 5 mL of 2.5% NaOCl at each change of instrument and received a final flush with 17% EDTA for 1 min. After instrumentation, the roots were split longitudinally and SEM micrographs at x 100 and x 1,000 were taken to evaluate the amount of debris and smear layer, respectively, in each third. Data were analyzed by KruskalWallis and Dunn's post-hoc tests (a = 5%). Manual dynamic activation left significantly (p < 0.05) more debris inside the canals than the other protocols, while ultrasonic irrigation and EndoVac were the most effective (p < 0.05) for debris removal. Regarding the removal of smear layer, there was no statistically significant difference (p > 0.05) either among the irrigant agitation protocols or between the protocolcanal third interactions. Although none of the irrigant agitation protocols completely removed debris and smear layer from flattened root canals, the machine-assisted agitation systems (ultrasound and EndoVac) removed more debris than the manual techniques. Microsc. Res. Tech. 75:781790, 2012. (C) 2011 Wiley Periodicals, Inc.

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The aim of this study was to evaluate the efficacy of three rotary instrument systems (K3, Pro Taper and Twisted File) in removing calcium hydroxide residues from root canal walls. Thirty-four human mandibular incisors were instrumented with the Pro Taper System up to the F2 instrument, irrigated with 2.5% NaOCl followed by 17% EDTA, and filled with a calcium hydroxide intracanal dressing. After 7 days, the calcium hydroxide dressing was removed using the following rotary instruments: G1. - NiTi size 25, 0.06 taper, of the K3 System; G2 - NiTi F2, of the Pro Taper System; or G3 - NiTi size 25, 0.06 taper, of the Twisted File System. The teeth were longitudinally grooved on the buccal and lingual root surfaces, split along their long axis, and their apical and cervical canal thirds were evaluated by SEM (x1000). The images were scored and the data were statistically analyzed using the Kruskall Wallis test. None of the instruments removed the calcium hydroxide dressing completely, either in the apical or cervical thirds, and no significant differences were observed among the rotary instruments tested (p > 0.05).

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Objective: The aim of this prospective study was to compare the dentoalveolar effects produced by two types of palatal crib, removable (Rpc+C) and fixed (Fpc+C), combined with chincup in growing patients with anterior open bite. Material and Methods: Each group comprised 30 patients, in the mixed dentition phase, with similar cephalometric characteristics and skeletal ages. Group 1 (Rpc+ C) presented initial mean age of 8.3 years and mean anterior open bite of 4.0 mm. Group 2 (Fpc+C) presented initial mean age of 8.54 years and mean anterior open bite of 4.3 mm. The evaluation period comprised 12 months between initial (T1) and second lateral radiograph (T2). The T2-T1 changes were compared cephalometrically in the 2 groups using the non-paired t-test. Results: Vertical changes in the posterior dentoalveolar region were similar between the groups (about 1 mm) and no significant differences were found in molar mesialization. The Fpc+C group had in average 1.6 mm more improvement of the overbite as a result of greater maxillary incisor extrusion (1.3 mm). Patients in this group also presented less lingual tipping of maxillary incisors and more mandibular incisors uprighting. Conclusions: The Fpc+C combination was more efficient in the correction of the negative overbite mainly due to greater extrusion of the maxillary incisors. However, the Rpc+C appliance promoted better upper and lower incisor inclination, resulting in a more adequate overjet.

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Objective: To evaluate the dentoskeletal changes of Class II malocclusion treatment with the Twin Force Bite Corrector (TFBC). Materials and Methods: The sample comprised 86 lateral cephalograms obtained from 43 subjects with Class II division 1 malocclusion; the subjects were divided into two groups. The experimental group comprised 23 patients with a mean initial age of 12.11 years who were treated with the TFBC for a mean period of 2.19 years. The control group included 40 lateral cephalograms from 20 Class II nontreated patients, with an initial mean age of 12.55 years and a mean observation period of 2.19 years. The lateral cephalograms were evaluated before and after orthodontic treatment in group 1 and in the beginning and end of the observation period in group 2. t-Tests were used to compare the initial and final cephalometric characteristics of the groups as well as the amount of change. Results: The experimental group presented greater maxillary growth restriction and mandibular retrusion than the control group, as well as greater maxillomandibular relationship improvement and greater labial tipping of the mandibular incisors. The results also showed a greater decrease in overbite and overjet in the experimental group, and there were no statistically significant differences in the craniofacial growth pattern between groups. Conclusions: The TFBC promotes restriction of anterior maxillary displacement without significant changes in mandibular length and position and improvement of maxillomandibular relationship without changes in facial growth and significant buccal tipping of mandibular incisors. Class II correction with the TFBC occurred primarily as a result of dentoalveolar changes.

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Introduction: The aim of this prospective clinical study was to investigate the cephalometric changes produced by bonded spurs associated with high-pull chincup therapy in children with Angle Class I malocclusion and anterior open bite. Methods: Thirty patients with an initial mean age of 8.14 years and a mean anterior open bite of 3.93 mm were treated with bonded spurs associated with chincup therapy for 12 months. An untreated control group of 30 subjects with an initial mean age of 8.36 years and a mean anterior open bite of 3.93 mm and the same malocclusion was followed for 12 months for comparison. Student t tests were used for intergroup comparisons. Results: The treated group demonstrated a significantly greater decrease of the gonial angle, and increase in overbite, palatal tipping of the maxillary incisors, and vertical dentoalveolar development of the maxillary and mandibular incisors compared with the control group. Conclusions: The association of bonded spurs with high-pull chincup therapy was efficient for the correction of the open bite in 86.7% of the patients, with a 5.23-mm (SD, 61.69) overbite increase.

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Introduction: The aim of this study was to compare the dentoskeletal changes of patients with Class II Division 1 malocclusion treated with either the Jasper jumper appliance or the activator-headgear combination, both associated with fixed appliances. Methods: The sample comprised 72 subjects with Class II Division 1 malocclusion divided into 3 groups: group 1 included 25 subjects treated with fixed appliances and the force modules of the Jasper jumper at an initial mean age of 12.72 years, group 2 included 25 subjects treated with the activator-headgear combination followed by fixed appliances at an initial mean age of 11.07 years, and group 3 included 22 untreated subjects at an initial mean age of 12.67 years. Initial cephalometric characteristics and dentoskeletal changes were compared with analysis of variance. Results: Both experimental groups had similar dentoskeletal changes: restrictive effect on the maxilla, clockwise mandibular rotation and a slight increase in anterior face height, retrusion of the maxillary incisors, distalization of the maxillary molars, protrusion of the mandibular incisors, extrusion of the mandibular molars, and significant improvements of the maxillomandibular relationship, overjet, overbite, and the molar relationship. Conclusions: The effects of the Jasper jumper and the activator-headgear combination followed by fixed orthodontic appliances were similar in Class II malocclusion treatment.

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INTRODUCTION: The opinion on the 'straight-wire' concept has been evolving since its origin, characterized by faithful followers or absolute skepticism. Currently, it seems reasonable to state that most professionals have a more realistic and critical viewpoint, with an attitude that reveals Orthodontics' maturity and greater knowledge on the technique. The most relevant criticisms refer to the impossibility of the both the Straight-Wire and the Standard systems to completely express the characteristics related to the brackets due to mechanical deficiencies, such as bracket/wire play. OBJECTIVES: A critical analysis of this relationship, which is unclear due to lack of studies, was the scope of this paper. METHODS: The compensatory treatment of two patients, using Capelozza's individualized brackets, works as the scenery for cephalometric evaluation of changes in incisor inclination produced by different dimensions of leveling archwires. RESULTS: The evaluation of these cases showed that, while the introduction of a 0.019 x 0.025-in stainless steel archwire in a 0.022 x 0.030-in slot did not produce significant changes in incisor inclination, the 0.021 x 0.025-in archwire was capable of changing it, mainly in mandibular incisors, and in the opposite direction to the compensation. CONCLUSION: Considering compensatory treatments, even when using an individualized prescription according to the malocclusion, the bracket/wire play seems to be a positive factor for malocclusion correction, without undesirable movements. Therefore, it seems reasonable to admit that, until a bracket system can have absolute individualization, the use of rectangular wires that still have a certain play with the bracket slot is advisable.

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OBJECTIVE: This study aimed to evaluate the cephalometric effects promoted by the orthodontic treatment of Class II malocclusion patients with the use of the 10-Hour Force Theory, that consists in the use of fixed appliances with 8 hours a day using a cervical headgear appliance and 16 hours a day using Class II elastics, 8 hours on the first mandibular molar and 8 hours in the second mandibular molar. METHODS: Sample comprised 31 patients with mean initial age of 14.90 years, final mean age of 17.25 years and mean treatment time of 2.35 years. The lateral cephalograms in pre-treatment and post-treatment stages were evaluated. Evaluation of cephalometric changes between initial and final treatment phases was performed by paired t test. RESULTS: The cases treated with the 10-Hour Force Theory presented a slight restriction of anterior displacement of the maxilla, increase in the effective length of the mandible, significant improvement of the maxillomandibular relationship, significant increase in anterior lower face height, distal tipping of the maxillary premolar crowns, extrusion and distal tipping of the roots of maxillary molars, significant proclination and protrusion of mandibular incisors, significant extrusion and mesialization of mandibular molars, besides a significant correction of the molar relationship, overjet and overbite. CONCLUSION: The use of the 10-Hour Force Theory in treatment of Class II malocclusion provided satisfactory results.

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OBJECTIVE: The aim of this prospective study was to cephalometrically analyze the stability of dentoalveolar and skeletal changes produced by a removable appliance with palatal crib associated to high-pull chincup in individuals with anterior open bite treated for 12 months, and compare them to individuals with similar malocclusion and age, not submitted to orthodontic treatment, also followed for the same period. METHODS: Nineteen children with a mean age of 9.78 years old treated for 12 months with a removable appliance with palatal crib associated with chincup therapy were evaluated after 15 months (post-treatment period) and compared with a control group of 19 subjects with mean age of 9.10 years with the same malocclusion that was followed-up for the same period. Seventy-six lateral cephalograms were evaluated at T1 (after correction) and T2 (follow-up) and cephalometric variables were analyzed by statistical tests. RESULTS: The results did not show significant skeletal, soft tissue or maxillary dentoalveolar changes. Overall, treatment effects on the experimental group were maintained at T2 evaluation with an increase of 0.56 mm in overbite. Overjet and maxillary incisors/molars position (vertical and sagittal) remained essentially unchanged during the study period. Only mandibular incisors showed significant changes (labial inclination and protrusion) compared to control group. CONCLUSIONS: Thus, it can be concluded that the early open bite treatment with a removable appliance and palatal crib associated with high-pull chincup therapy provided stability of 95%.

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OBJECTIVES To evaluate the long-term development of labial gingival recessions during orthodontic treatment and retention phase. MATERIAL AND METHODS In this retrospective case-control study, the presence of gingival recession was scored (Yes or No) on plaster models of 100 orthodontic patients (cases) and 120 controls at the age of 12 (T12 ), 15 (T15 ), 18 (T18 ), and 21 (T21 ) years. In the treated group, T12 reflected the start of orthodontic treatment and T15 - the end of active treatment and the start of retention phase with bonded retainers. Independent t-tests, Fisher's exact tests and a fitted two-part "hurdle" model were used to identify the effect of orthodontic treatment/retention on recessions. RESULTS The proportion of subjects with recessions was consistently higher in cases than controls. Overall, the odds ratio for orthodontic patients as compared with controls to have recessions is 4.48 (p < 0.001; 95% CI: 2.61-7.70). CONCLUSIONS Within the limits of the present research design, orthodontic treatment and/or the retention phase may be risk factors for the development of labial gingival recessions. In orthodontically treated subjects, mandibular incisors seem to be the most vulnerable to the development of gingival recessions.

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OBJECTIVE To evaluate the long-term effects of asymmetrical maxillary first molar (M1) extraction in Class II subdivision treatment. MATERIALS AND METHODS Records of 20 Class II subdivision whites (7 boys, 13 girls; mean age, 13.0 years; SD, 1.7 years) consecutively treated with the Begg technique and M1 extraction, and 15 untreated asymmetrical Class II adolescents (4 boys, 11 girls; mean age, 12.2 years; SD, 1.3 years) were examined in this study. Cephalometric analysis and PAR assessment were carried out before treatment (T1), after treatment (T2), and on average 2.5 years posttreatment (T3) for the treatment group, and at similar time points and average follow-up of 1.8 years for the controls. RESULTS The adjusted analysis indicated that the maxillary incisors were 2.3 mm more retracted in relation to A-Pog between T1 and T3 (β  =  2.31; 95% CI; 0.76, 3.87), whereas the mandibular incisors were 1.3 mm more protracted (β  =  1.34; 95% CI; 0.09, 2.59), and 5.9° more proclined to the mandibular plane (β  =  5.92; 95% CI; 1.43, 10.41) compared with controls. The lower lip appeared 1.4 mm more protrusive relative to the subnasale-soft tissue-Pog line throughout the observation period in the treated adolescents (β  =  1.43; 95% CI; 0.18, 2.67). There was a significant PAR score reduction over the entire follow-up period in the molar extraction group (β  =  -6.73; 95% CI; -10.7, -2.7). At T2, 65% of the subjects had maxillary midlines perfectly aligned with the face. CONCLUSIONS Unilateral M1 extraction in asymmetrical Class II cases may lead to favorable occlusal outcomes in the long term without harming the midline esthetics and soft tissue profile.

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Este estudo teve como finalidade avaliar cefalometricamente, por meio de telerradiografias em norma lateral, as alterações dento-esqueléticas em pacientes Classe III submetidos a tratamento ortodôntico-cirúrgico. A amostra experimental constituiu-se de 16 pacientes Brasileiros, dos sexos masculino e feminino, na faixa etária pré-cirúrgica média de 21 anos e 11 meses, apresentando má oclusão de Classe III com indicação de tratamento cirúrgico representado por recuo mandibular isolado. Para cada paciente foram realizadas telerradiografias nas fases inicial, pré-cirúrgica e pós-cirúrgica, sendo comparadas a um grupo controle, constituído de telerradiografias de indivíduos com oclusão normal. Segundo a metodologia empregada e pela análise dos resultados obtidos, avaliados estatisticamente, constatou-se que os pacientes Classe III com indicação de recuo mandibular foram caracterizados por um mau relacionamento entre as bases esqueléticas representado por um bom posicionamento da maxila associado a prognatismo mandibular, aumento da altura facial ântero-inferior, incisivos inferiores e sínfise mandibular lingualizados e incisivos superiores vestibularizados. A partir do preparo ortodôntico pré-cirúrgico, observou-se uma rotação mandibular no sentido horário, descompensação dentária representada por lingualização e extrusão dos incisivos superiores e vestibularização dos incisivos inferiores, acompanhada por uma remodelação da cortical óssea vestibular da sínfise mandibular. Esta descompensação ortodôntica definiu características dento-alveolares semelhantes às dos indivíduos com oclusão normal. O comportamento das variáveis dento-esqueléticas após a cirurgia ortognática, a partir do deslocamento póstero-superior das estruturas dento-esqueléticas da mandíbula, proporcionou um equilíbrio destas estruturas, em relação à oclusão normal.

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Este estudo teve como finalidade avaliar cefalometricamente, por meio de telerradiografias em norma lateral, as alterações dento-esqueléticas em pacientes Classe III submetidos a tratamento ortodôntico-cirúrgico. A amostra experimental constituiu-se de 16 pacientes Brasileiros, dos sexos masculino e feminino, na faixa etária pré-cirúrgica média de 21 anos e 11 meses, apresentando má oclusão de Classe III com indicação de tratamento cirúrgico representado por recuo mandibular isolado. Para cada paciente foram realizadas telerradiografias nas fases inicial, pré-cirúrgica e pós-cirúrgica, sendo comparadas a um grupo controle, constituído de telerradiografias de indivíduos com oclusão normal. Segundo a metodologia empregada e pela análise dos resultados obtidos, avaliados estatisticamente, constatou-se que os pacientes Classe III com indicação de recuo mandibular foram caracterizados por um mau relacionamento entre as bases esqueléticas representado por um bom posicionamento da maxila associado a prognatismo mandibular, aumento da altura facial ântero-inferior, incisivos inferiores e sínfise mandibular lingualizados e incisivos superiores vestibularizados. A partir do preparo ortodôntico pré-cirúrgico, observou-se uma rotação mandibular no sentido horário, descompensação dentária representada por lingualização e extrusão dos incisivos superiores e vestibularização dos incisivos inferiores, acompanhada por uma remodelação da cortical óssea vestibular da sínfise mandibular. Esta descompensação ortodôntica definiu características dento-alveolares semelhantes às dos indivíduos com oclusão normal. O comportamento das variáveis dento-esqueléticas após a cirurgia ortognática, a partir do deslocamento póstero-superior das estruturas dento-esqueléticas da mandíbula, proporcionou um equilíbrio destas estruturas, em relação à oclusão normal.