Renato Rodrigues de Almeida

Short-Term Treatment Effects Produced by the Herbst Appliance in the Mixed Dentition

This prospective clinical investigation evaluates the dentoalveolar and skeletal cephalometric changes produced by the Herbst appliance during treatment of mixed dentition patients with Class II division 1 malocclusion. Thirty individuals (15 male and 15 female individuals; initial mean age nine years 10 months) were treated with the Herbst appliance for a period of 12 months. For comparison, the records of 30 untreated Class II children (15 boys, 15 girls; initial mean age nine years eight months) were followed without treatment for a period of 12 months. The results indicated that the treatment effects produced in the mixed dentition patients were primarily dentoalveolar in nature. The mandibular incisors were tipped labially, and the maxillary incisors were retruded; a significant increase in mandibular posterior dentoalveolar height occurred, and there was a restriction in the vertical development of the maxillary molars. There was no difference in the forward growth of the maxilla between the two groups. In comparison with the controls, however, the Herbst treatment produced a modest but statistically significant increase in total mandibular length. This increase in total mandibular length, however, was less than that observed in adolescent Herbst patients in other studies.

Comparison of root resorption between self-ligating and conventional preadjusted brackets using cone beam computed tomography.

OBJECTIVEnTo compare the magnitude of external apical root resorption (EARR) of incisors in patients undergoing the initial phase of orthodontic treatment with two sets of brackets.nnnMATERIALS AND METHODSnAccording to the results of the power analysis for sample size calculation, 19 Angle Class I patients (anterior crowding: 3 to 5 mm; mean age: 20.6 years) were included in the study and randomly divided into two groups: group I (n u200a=u200a 11, self-ligating brackets) and group II (n u200a=u200a 8, conventional preadjusted brackets). The degree of EARR was detected in 152 upper and lower incisors by using cone-beam computed tomography (CBCT) scans and a three-dimensional program (Dolphin 11.5, Dolphin Imaging & Management Solutions, Chatsworth, Calif) with 25% level of sensitivity. The CBCT scans were obtained before (T1) and 6 months after initiation of treatment (T2). Differences between and within groups were analyzed by nonpaired and paired t-test, respectively, with 5% significance level.nnnRESULTSnSignificant differences were found for both groups between T1 and T2. However, no differences in the degree of EARR were detected between the groups studied.nnnCONCLUSIONSnAlthough EARR has occurred in all teeth evaluated, the bracket design (self-ligating or conventional) did not demonstrate any influence on the results observed.

Comparison of manual, digital and lateral CBCT cephalometric analyses

Objective: The aim of this study was to compare the reliability of three different methods of cephalometric analysis. Material and Methods: Conventional pretreatment lateral cephalograms and cone beam computed tomography (CBCT) scans from 50 subjects from a radiological clinic were selected in order to test the three methods: manual tracings (MT), digitized lateral cephalograms (DLC), and lateral cephalograms from CBCT (LC-CBCT). The lateral cephalograms were manually analyzed through the Dolphin Imaging 11.0(tm) software. Twenty measurements were performed under the same conditions, and retraced after a 30-day period. Paired t tests and the Dahlberg formula were used to evaluate the intra-examiner errors. The Pearsons correlation coefficient and one-way analysis of variance (ANOVA) tests were used to compare the differences between the methods. Results: Intra-examiner reliability occurred for all methods for most of the measurements. Only six measurements were different between the methods and an agreement was observed in the analyses among the 3 methods. Conclusions: The results demonstrated that all evaluated methodologies are reliable and valid for scientific research, however, the method used in the lateral cephalograms from the CBCT proved the most reliable.

Early Treatment Protocol for Skeletal Class III Malocclusion

Skeletal Class III malocclusion, with its unpredictable and unfavorable nature, has been characterized by a growth pattern with doubtful prognosis regarding orthodontic mechanics, even when performed early. For a long time, Class III malocclusion was regarded as a synonym of mandibular prognathism, regardless of the affected skeletal structures. Mandibular growth, essentially determined by genetic factors, could barely be controlled by early orthodontic interventions. Therefore, the treatment choice was to wait for the patient to grow, and then make an orthodontic intervention associated with an orthognathic surgery. Maxillary involvement in the etiology of Class III malocclusion was conclusive to change orthodontic therapeutics. Maxillary intramembranous growth has a better response to orthopedic treatment, based on growth control and redirection, thus contributing for early intervention success. In several cases, excellent results have been achieved with rapid maxillary expansion and protraction. The aim of this study was to describe and discuss the treatment of a patient with Class III malocclusion, whose treatment planning comprised two phases: interceptive (mechanical orthopedic appliances) and comprehensive (fixed orthodontic appliance). The results of this case showed that Class III malocclusion should be intercepted as early as possible to permit growth redirection, mainly when the maxilla is the primary etiologic factor or dental and/or functional factors are involved. Diagnosis, treatment planning and prognosis depend on patient age, growth potential and severity of malocclusion. Early intervention, adequate indication of appliances, and patient compliance are key factors for good outcomes.

Estudo comparativo das alterações dentoesqueléticas da má-oclusão de Classe II, 1ª divisão de Angle, nos jovens sem tratamento e nos submetidos a dois tipos de aparelhos ortodônticos

The purpose of this study was to compare the skeletal and dental changes of the Class II, division 1 malocclusions with and without treatment. Seventy five patients were divided in three groups: control, treated with a modified maxillary splint and treated with fixed appliance and Kloehn headgear, each one having thirteen males and twelve females. The cephalometric radiographs were traced and analyzed by means of the Dentofacial Planner software. The results showed that there is little change in the pattern of growth and that the anteroinferior facial height increases in the three groups. There is no significant improvement in the maxillomandibular relationship in the control group, while in the treatment groups, the maxilla seemed to be retracted with a significant decrease in the ANB angle. The dentoalveolar changes showed that the appliance used in the second group is efficient in controlling the vertical extrusion of the upper teeth. In both treated groups, they are moved distally, leading to a normal molar relationship and the reduction of the overjet. In the controls, however, the teeth continue to develop in an anteroinferior direction, maintaining the Class II characteristics.

Assessment of facial profile changes in patients treated with maxillary premolar extractions

OBJETIVO: avaliar as alteracoes do perfil facial decorrentes do tratamento ortodontico com extracoes de dois primeiros pre-molares superiores, sob a optica de ortodontistas, cirurgioes-dentistas e leigos. METODOS: foram tracados os perfis faciais das telerradiografias pre- e pos-tratamento de 70 pacientes com ma oclusao de Classe II, divisao 1, e foi montado um album com as silhuetas dos 70 pacientes, de forma aleatoria, sendo dois perfis em cada folha do mesmo paciente. A seguir, 30 ortodontistas, 30 cirurgioes-dentistas e 30 leigos escolheram o perfil facial mais estetico (A ou B), e a quantidade de alteracao que percebiam entre os dois perfis pre- e pos-tratamento, de acordo com a escala visual analogica (EVA). RESULTADOS: os resultados revelaram que 83 examinadores preferiram o perfil pos-tratamento, sendo que somente tres cirurgioes-dentistas e quatro leigos escolheram com maior frequencia os perfis pre-tratamento. Assim, os ortodontistas escolheram mais frequentemente os perfis pos-tratamento, seguidos pelos cirurgioes-dentistas, sem diferenca estatisticamente significativa entre cirurgioes-dentistas e leigos. Houve diferenca estatisticamente significativa intragrupos na preferencia do perfil pre- e pos-tratamento. Alem disso, os tres grupos de avaliadores indicaram que os perfis pre- e pos-tratamento nao diferiram substancialmente. CONCLUSOES: o tratamento da ma oclusao de Classe II, divisao 1, com extracao de dois primeiros pre-molares produziu um efeito positivo na estetica do perfil facial.

Alterações dentoesqueléticas e do perfil facial em pacientes tratados ortodonticamente com extração de quatro primeiros pré-molares

OBJECTIVE: the purpose of this prospective study was to cephalometrically analyze the dentoalveolar and soft tissue changes after the orthodontic treatment followed by the extraction of four premolars. MATERIAL ANS METHODS: the sample was comprised by 30 Class II division 1 patients with mean initial age of 12 years and 4 months. Two lateral cephalograms were obtained from each patient at the beginning and at the end of the treatment. The variables analyzed were the nasalabial changes and upper and lower incisors changes in relation to a vertical and horizontal x and y reference lines. RESULTS: upper and lower incisors retraction was 3.4 and 1.8mm, respectively. The SNA angle was decresead by 1.7 degrees followed by a retraction of point A mainly due to the upper incisor retraction. There was a significant decrease of the Wits and ANB variables. There was an increase in the lower anterior facial height. Upper incisor retraction was followed by an increase in the nasolabial angle (ratio 1:2.8 degrees). However, a wide range of individual variability was found. CONCLUSIONS: the present study did not support the simple expectation that treatment with extractions of four premolars will result in a dished in face. It appeared that facial changes were more related to a normal facial growth, the amount of incisor retraction and the anchorage control during the upper and lower incisor.

Avaliação microbiológica da contaminação residual em diferentes tipos de alicates ortodônticos após desinfecção com álcool 70

AIM: The aim of this study was to verify, by means of microbiological analysis, the contamination in different kinds of orthodontic pliers (Distal End Cutter, Bird Beak, Band Remover and Weingart), after washing with water and detergent and followed by disinfection with 70% alcohol for 1 minute. METHODS: All the pliers were, initially, sterilized in autoclave for 20 minutes, at 121oC and 1atm of pressure. After the orthodontic appointment, the pliers were adequately transported to Microbiology Laboratory and the evaluations of variety and quantity of bacteria were made. Afterward, the same pliers were washed with water and detergent, and rubbed with gauze with 70% alcohol (p/p) for 1 minute. New bacteriological tests were done and compared to a control group of non utilized pliers. RESULTS: Results showed a great quantity and variety of residual bacteria after the disinfection with alcohol. CONCLUSIONS: Even pliers not inserted in patient mouth, but only handed by clinician, should be sterilized, once merely disinfection is not an adequate method for infection control.

Diastema interincisivos centrais superiores: quando e como intervir?

Contemporaneamente, os diastemas interincisivos centrais superiores sao vistos como um fator antiestetico sendo altamente prejudicial do ponto de vista social. O diagnostico diferencial dessa anomalia da oclusao deve ser realizado o mais cedo possivel, nao so para orientar o paciente e seus pais bem como para encetar o tratamento procurando devolver ao paciente uma estetica agradavel e o bem estar social. Na realidade o diastema mediano constitui um aspecto de normalidade durante a infância e com o desenvolvimento da oclusao ha um fechamento fisiologico significativo. A sua persistencia depende da etiologia que e multifatorial e geralmente esta relacionada a: discrepância dente-osso positiva, microdontia, agenesias dos incisivos laterais superiores, habitos principalmente de succao, dentes supranumerarios irrompidos ou ainda intra-osseo, hereditariedade, freio labial hipertrofico e outros. O objetivo principal desse trabalho e o de nortear o leitor com relacao a epoca (quando) e como intervir para o cerramento desse espaco. Resumo

Dentoskeletal effects produced by removable palatal crib, bonded spurs, and chincup therapy in growing children with anterior open bite

OBJECTIVEnTo evaluate the dentoskeletal effects of different anterior open bite treatment modalities in children.nnnMATERIALS AND METHODSnThis cephalometric study assessed changes resulting from different treatment approaches on 77 growing children with anterior open bite. A control group (n = 30) was used for comparison. Lateral cephalograms were available before treatment and after 12 months. The sample was divided into four groups: removable palatal crib associated with a chincup (G1), bonded spurs associated with a chincup (G2), chincup (G3), and nontreated control (G4). Statistical comparisons among the four groups were performed on T1 and the treatment changes using analysis of variance with Tukeys post hoc tests.nnnRESULTSnNo statistically significant changes in skeletal variables were found among the groups, except for lower anterior face height (LAFH) increase in G1. Overall, effects in all of the treated groups were exclusively dentoalveolar. A larger overbite (OB) increase was observed in G1 and G2 when compared with G3 and G4. The maxillary incisors in G1 showed increased palatal tipping, retrusion, and more vertical dentoalveolar development as well as increased lingual tipping among mandibular incisors. There was less vertical development of maxillary and mandibular molars in G3.nnnCONCLUSIONSnA removable palatal crib provided an improvement in OB (97.5%), followed by the bonded spurs (84.5%). Conversely, the chincup-only group did not have positive OB effects.