Linear measurement accuracy of CBCT panoramic reconstructions: experimental study with dry human mandibles.

INTRODUCTION: Studies on software accuracy of reformatted panoramic computed tomography (CT) images are scarce. OBJECTIVES: The aim of this study was to evaluate the software accuracy of reformatted panoramic views from cone-beam computed tomography (CBCT). METHODS: Ten dry mandibles were scanned using CBCT with different voxel sizes. Following the reconstruction of panoramic views with three different software, horizontal and vertical linear measurements were performed using the electronic rules of each software. Measurements of the corresponding dry mandibles were taken with a digital caliper and defined as the gold standard. RESULTS: There were no statistically significant differences in linear distances among the dry mandibles and reformatted panoramic CT views. The relative error ranged from 1.3 to 8.0%, depending on the software and voxel size. CONCLUSIONS: The linear measurements on reformatted panoramic views are reliable.

Dimensional error of three-dimensional images generated by different software.

The aim of this study was to evaluate the accuracy of three-dimensional (3D) reconstructions generated by different software, computed tomography (CT) scanners and slice thicknesses. Ten human dry mandibles were scanned by CT and cone beam CT (CBCT). Digital files were processed in different software systems and 3D reconstructions were performed. Linear measures were made and compared. The results showed significant differences in linear distances between the human dry mandibles and their 3D reconstructions. The relative error from CBCT images ranged from 3.10 to 4.82% and from 3.40 to 5.92% in CT images. It is important to consider that the performance of the software is not just related to the algorithm used, but mostly with its handling, that can facilitate or not the measurement by the operator. In conclusion, the discrepancies were not greater than 0.58 mm, so they should not affect the image quality.

Hábitos de higiene bucal e dieta de adolescentes de escolas públicas e privadas em Salvador, Bahia / Habits of oral hygiene and diet of adolescents of public and private schools in Salvador, Bahia

Objetivo: Obter informações acerca desses hábitos. Material e métodos: Aplicou-se um questionário estruturado para 1035 adolescentes de escolas públicas e privadas no município de Salvador-Bahia. Os dados foram consolidados no SPSS, versão 7.5. Resultados: Segundo os resultados, as razões pelas quais eles escovam os dentes são: revenção de cárie (54,8%) ou outras doenças (14,7%), higiene (43,9%), hálito bom (33,2%), estética (19,7%) e convívio social (3,3%). A maioria (98,5%), escova os dentes todos os dias, e destes, 67,4% escova três ou mais vezes ao dia. Quanto ao uso do fio dental, 33,8% não o utilizam e dos 66,2% que relataram usá-lo, 51,5% o fazem de vez em quando. Relativo à dieta 58% responderam que lancham mais de três vezes ao dia e dentre os alimentos mais consumidos estão os doces, salgadinhos e refrigerantes. Conclusão: Concluímos que os adolescentes relataram boa rotina de escovação, entretanto o uso do fio dental não se constitui em um hábito. Os alimentos consumidos são altamente cariogênicos e a freqüência de consumo é alta. É imprescindível, desse modo, o desenvolvimento de programas de promoção de saúde bucal paraesse grupo populacional.

Objective: Thus, the proposal of this work was to get information about these habits. Material and methods: A structuralized questionnaire was applied to 1035 adolescents of public and private schools in the city of Salvador-Bahia. The data had been consolidated in the SPSS, version 7.5.Results: According to the results, the reasons for which they brush teeth are: prevention of caries (54,8%) or other oral diseases (14,7%), hygiene (43,9%), good breath (33,2%), aesthetic (19,7%) and social conviviality (3,3%). The majority (98,5%), brushes teeth every day, and of these, 67.4% brush three or more times on a day. 33.8% do not use dental wireand 66.2% of those that had told to use it, 51.5% only do it sometimes. Relative to diet, 58% answered that they eat snacks more than tree times a day and among the consumed foods most of them are the candies, chips and soda. Conclusion: We conclude that the adolescents had a goodroutine of teeth brushing; however the use of the dental wire does not consist in a habit. The consumed foods are of high cariogenic potential and the consumption frequency is high. It is essential, in this way, the development of programs to promote oral health for this population group.

Tratamento de defeitos alveolares verticais pela técnica de distração osteogênica / Treatment of vertical alveolar defects by means of osteogenic distraction technique

Introdução: a reconstrução alveolar de defeitos ósseos verticais ainda constitui um desafio dentro da Implantodontia. Dentre as diversas técnicas empregadas para a correção de tais defeitos, está a distração osteogênica, a qual tem sido descrita como uma técnica empregada para ganho de tecido ósseo e tecidos moles, sobretudo em cirurgias para reconstrução de rebordos alveolares mandibulares e maxilares, com a finalidade de permitir a instalação de implantes osseointegrados bem posicionados e com maior previsibilidade de sucesso quando submetidos a cargas funcionais. Objetivo: o propósito desse estudo foi avaliar a efetividade do procedimento em dois pacientes tratados pela técnica de distração osteogênica alveolar Relato de caso: os casos clínicos foram avaliados quanto ao ganho ósseo através de exame clínico e radiográfico, pré e pós-distração. Resultados: em ambos os casos, constatou-se, ao final do tratamento, ganho ósseo suficiente para posterior reabilitação com implantes. Conclusão: o sucesso relatado na literatura e nos casos apresentados comprova a eficiência da técnica e sua viabilidade clínica.

Introduction: Alveolar reconstruction of vertical bone defects remains a daunting challenge in implant dentistry. Among the various techniques used to correct such defects is distraction osteogenesis (DO), which has been described as a technique used to gain bone and soft tissues, especially in surgeries for reconstruction of mandibular and maxillary alveolar ridges to allow the placement of dental implants in a favorable position and with greater success predictability when subjected to functional loads. Objective: The purpose of this studywas to evaluate the effectiveness of DO in two patients treated with the technique of alveolar distraction osteogenesis. Case report: The clinical cases were evaluated for bone gain through clinical and radiographic examination, pre- and post-distraction. Results: At the end of treatment, both cases had gained sufficient bone as to enable subsequent rehabilitation with implants. Conclusions: The success rate reported in the literature and in the cases presented here prove the efficiency of the technique and its clinical feasibility.