USE OF MOUTHWASH AND DENTIFRICE CONTAINING AN ANTIMICROBIAL PHTHALOCYANINE DERIVATIVE FOR THE REDUCTION OF CLINICAL SYMPTOMS OF COVID-19: A RANDOMIZED TRIPLE-BLIND CLINICAL TRIAL.

PURPOSE: This clinical trial aimed to evaluate the use of mouthwash and dentifrice containing an antimicrobial phthalocyanine derivative (APD) to reduce the clinical symptoms in patients with COVID-19. METHODS: This randomized, triple-blind clinical trial enrolled 134 patients aged 18 years or older who underwent COVID-19 testing through the use of nasopharyngeal swab RT-qPCR in a reference center for the diagnosis of COVID-19, had no clinical contraindications to mouthwash and gargle, and had access to cell phones with communication applications. According to the use of a mouthwash and dentifrice containing antimicrobial phthalocyanine derivatives (APD), patients were randomly assigned (1:1) to the APD or non-APD (control) group. All participants were instructed to floss twice a day, brush teeth for 2 minutes 3 times a day, and gargle/rinse (5 mL) for 1 min/3 times a day for 7 days. An online questionnaire was sent to collect data on the clinical symptoms of COVID-19 3 times: T0 (baseline before using the oral hygiene products), T3 (3 days after), and T7 (7 days after). The investigators, patients, and outcome assessors were blinded to group assignment. The Mann-Whitney, Chi-Square, Fisher's exact, and Cochran's tests were used according to the nature of the variables studied, with the level of significance set at P < .05. RESULTS: No statistically significant difference was found in the prevalence of symptoms between groups at baseline. A statistically significant reduction in clinical symptoms was found in the control group (fatigue, shortness of breath, hoarse voice, sore throat, nasal congestion, and chest pain) and APD group (cough, fatigue, shortness of breath, hyposmia/anosmia, dysgeusia, hoarse voice, sore throat, nasal congestion, chest pain, diarrhea, and irritability/confusion) during the follow-up period. There were statistically significant differences, with a higher prevalence of symptoms in the control group at T3 and T7. Dysgeusia, sore throat, and irritability/confusion were less prevalent in the APD group at T3, and shortness of breath, hyposmia/anosmia, dysgeusia, hoarse voice, sore throat, diarrhea, and irritability/confusion were more prevalent in the control group at T7. CONCLUSIONS: Based on this methodology, the results demonstrated that the regular use of mouthwash and dentifrice-containing APD had a positive impact on the clinical symptoms, as reported by patients with COVID-19.

A single session of antimicrobial photodynamic therapy does not influence the alveolar repair process in rats.

The aim of this study was to use microscopic and molecular techniques to evaluate the effects of a single session of antimicrobial photodynamic therapy (aPDT) on the alveolar repair process after tooth extraction in rats. The study sample included 84 rats divided into four groups, as follows: a) Control - untreated socket; b) Laser - socket treated using photobiomodulation; c) TBO - socket treated with topic application of the photosensitizer agent, toluidine blue O (TBO); and d) aPDT - socket treated with TBO and laser irradiation. An additional rat was used for thermal mapping during socket irradiation. The animals were euthanatized at 6, 15, and 28 days after unilateral extraction of the upper incisor. Quantitative and qualitative analyses of the connective and bone tissues, blood clot, blood vessel, and inflammatory infiltrate were performed, and real-time polymerase chain reaction was used to study the expression of genes (collagen type I, osteocalcin, alkaline phosphatase [ALP], runt-related transcription factor 2 [RUNX2], and vascular endothelial growth factor [VEGF]) involved in the bone healing process. No statistically significant differences in microscopic and molecular outcomes were observed between the groups (p > 0.05). A positive correlation was seen to exist between blood clot and VEGF (p = 0.000), and a negative correlation was observed between bone tissue and ALP (p = 0.028) and blood vessel and VEGF (p = 0.018). A single session of aPDT in the dental extraction site did not influence the alveolar repair process in rats.

A single session of antimicrobial photodynamic therapy does not influence the alveolar repair process in rats

Abstract: The aim of this study was to use microscopic and molecular techniques to evaluate the effects of a single session of antimicrobial photodynamic therapy (aPDT) on the alveolar repair process after tooth extraction in rats. The study sample included 84 rats divided into four groups, as follows: a) Control - untreated socket; b) Laser - socket treated using photobiomodulation; c) TBO - socket treated with topic application of the photosensitizer agent, toluidine blue O (TBO); and d) aPDT - socket treated with TBO and laser irradiation. An additional rat was used for thermal mapping during socket irradiation. The animals were euthanatized at 6, 15, and 28 days after unilateral extraction of the upper incisor. Quantitative and qualitative analyses of the connective and bone tissues, blood clot, blood vessel, and inflammatory infiltrate were performed, and real-time polymerase chain reaction was used to study the expression of genes (collagen type I, osteocalcin, alkaline phosphatase [ALP], runt-related transcription factor 2 [RUNX2], and vascular endothelial growth factor [VEGF]) involved in the bone healing process. No statistically significant differences in microscopic and molecular outcomes were observed between the groups (p > 0.05). A positive correlation was seen to exist between blood clot and VEGF (p = 0.000), and a negative correlation was observed between bone tissue and ALP (p = 0.028) and blood vessel and VEGF (p = 0.018). A single session of aPDT in the dental extraction site did not influence the alveolar repair process in rats.

Reliability and accuracy of automatic segmentation of mandibular 3D models on linear measurements.

OBJECTIVE: Evaluate if automatic segmentation of mandibular three-dimensional (3D) models is reliable and accurate. MATERIALS AND METHODS: Eight dry mandibles with eight silica markers were scanned in the i-CAT Classic device (Imaging Sciences International). Automatic segmentation was performed using nine standard preset thresholds in the Dolphin software (Dolphin Imaging & Management Solutions). Three observers individually made twice eight linear measurements on the mandibular 3D models. Another observer made physical measurements, twice as well, on the dry mandibles. Reliability and accuracy were evaluated with intraclass correlation coefficients (ICCs), Dahlberg's formula, Bland-Altman analyses, and changing bias with regression analyses. RESULTS: Inter-observer and intra-observer ICCs and Dahlberg's error were ≥ 0.75 and ≤ 1.0 mm, respectively, for all measurements. Inter-observer agreement between mandibular 3D models and physical measurements ranged from -0.37 to 0.91 mm. CONCLUSIONS: Linear measurements made on mandibular 3D models obtained using standard preset thresholds are reliable and accurate. However, additional studies are necessary to confirm this hypothesis for clinical applications. CLINICAL RELEVANCE: Since the 3D models are useful for diagnostics and surgical planning, it is necessary to determinate whether the linear measurements made on 3D models obtained by automatic segmentation are sufficiently reliable and accurate.

Analysis of the Preventative Influence of an Oral Hygiene Protocol on Ventilator-Associated Pneumonia / Análise da Influência Preventiva de um Protocolo de Higiene oral na Pneumonia Associada à Ventilação Mecânica

Ventilator-associated pneumonia (VAP) is the most commonly reported nosocomial infection among intensive care unit (ICU) patients. This study aimed to evaluate the influence of an oral hygiene protocol on VAP incidence among mechanically-ventilated (MV) ICU patients. The dentate patients admitted without VAP to the hospital's adult ICU requiring mechanical ventilation for ≥48 hours during a 4-month period in two consecutive years (2015 ­ Control group and 2016 ­ Experimental group) were included in this investigation. The oral hygiene protocol was implemented daily, once a day, in the morning hours, using a disposable brush with suction and ultrasoft bristles and 3 g of 0.12% chlorhexidine gel. Hospital-related respiratory infection data, including VAP diagnoses and microbiological analyses, were collected from the monthly health epidemiological notification bulletins issued by the hospital. T tests were applied to compare variables before versus after implementation of the oral hygiene protocol with a significance criterion of P < .05. 43.94% reduction in VAP rate after the protocol implementation was observed. Implementation of the protocol was associated with a significant reduction of Enterobacter spp infections and no cases of VAP related to the main etiological agents of the disease (i.e., S. aureus and C. albicans) were identified. It can be concluded that an oral hygiene protocol performed with a suction brush and 0.12% chlorhexidine gel can serve as an effective prophylaxis against VAP in patients under mechanical ventilation. (AU)

A pneumonia associada à ventilação (PAV) é a infecção nosocomial mais comumente relatada em pacientes de Unidade de Terapia Intensiva (UTI). Este estudo teve como objetivo avaliar a influência de um protocolo de higiene bucal na incidência de PAV entre pacientes sob ventilação mecânica (VM). Os pacientes dentados internados na UTI adulta do hospital sem PAV e que necessitaram de ventilação mecânica por ≥ 48 horas durante um período de 4 meses em dois anos consecutivos (2015 - grupo Controle e 2016 - grupo Experimental) foram incluídos nesta investigação. O protocolo de higiene bucal foi implementado diariamente, uma vez ao dia, nas primeiras horas da manhã, utilizando-se escova descartável com cerdas de sucção e ultramacia e 3 g de gel de clorexidina a 0,12%. Dados de infecção respiratória relacionada ao hospital, incluindo diagnósticos de PAV e análises microbiológicas, foram coletados dos boletins mensais de notificação epidemiológica de saúde emitidos pelo hospital. Testes t foram aplicados para comparar as variáveis antes e após a implementação do protocolo de higiene bucal com um critério de significância de P <0,05. Observamos uma redução de 43,94% na taxa de PAV após a implementação do protocolo A implementação do protocolo foi associada à uma redução significativa das infecções por Enterobacter spp e não foram identificados casos de PAV relacionados aos principais agentes etiológicos da doença (isto é, S. aureus e C. albicans). Pode-se concluir que u protocolo de higiene bucal realizado com escova de sucção e gel de clorexidina a 0,12% pode servir como uma profilaxia efetiva contra a PAV em pacientes sob ventilação mecânica. (AU)

Analysis of the Gray-Value Reproducibility and Noise of a Direct Digital Radiography System / Análise da Reprodutibilidade do Valor de Cinza e Ruído de um Sistema de Radiografia Digital Direto

The digital radiograph represents a great advance in oral maxillofacial radiology because it incorporates informatics technology in the capture, interpretation, and archiving of radiographic images. Previous studies have demonstrated that it is possible to use gray values in bone lesion diagnosis and follow-up. However, these applications depend on radiograph system quality and exposure time. The aim of this study was to evaluate the gray-value reproducibility and noise produced by Dabi Atlante's IDA system, a direct digital radiography system. Radiographs were obtained in a standardized manner (70 kV, 7 mA, and 2.2-mm filtration) with a direct digital sensor and a stepwedge placed in a phantom at a 30-cm focus-film distance. Ten consecutive x-ray imaging series were completed at 0.10-s, 0.15-s, and 0.20-s exposure times. Gray values were analyzed in five regions of interest (ROIs): bone tissue (BT), soft tissue (ST), and three stepwedge steps (Step 1, Step 2, and Step 3). Mean gray values differed significantly across exposure times (p < .05) in all five ROIs. The ROI with the greatest gray-value variability (25.36%) and noise (9.46%) was ST. In conclusion, gray-value reproducibility and noise of the IDA system vary across areas with differing radiolucency. Thus, special attention is necessary for the diagnosis and follow-up of radiolucent lesions due to relatively high gray-value interference (AU).

A radiografia digital representa um grande avanço na radiologia bucomaxilofacial porque incorpora a tecnologia informática na captura, interpretação e arquivamento de imagens radiográficas. Estudos anteriores demonstraram que é possível usar os valores de cinza no diagnóstico e na proservação das lesões ósseas. No entanto, essas aplicações dependem da qualidade do sistema radiológico e do tempo de exposição. O objetivo deste estudo foi avaliar a reprodutibilidade do valor de cinza e o ruído produzido pelo sistema IDA da Dabi Atlante, um sistema de radiografia digital direto. As radiografias foram obtidas de maneira padronizada (70 kV, 7 mA e filtração de 2,2 mm) com um sensor digital direto e um penetrômetro colocados em um fantoma a uma distância de filme-foco de 30 cm. Dez imagens radiográficas consecutivas foram obtidas com tempos de exposição de 0,10-s, 0,15-s e 0,20-s. Os valores de cinza foram analisados em cinco regiões de interesse (ROIs): tecido ósseo (TO), tecido mole (TM) e três degraus do penetrômetro (Degrau 1, Degrau 2 e Degrau 3). Os valores de cinza médios diferiram significativamente entre os tempos de exposição (p <0,05) em todos as cinco ROIs. A ROI com maior variabilidade do valor de cinza (25,36%) e ruído (9,46%) foi TM. Em conclusão, a reprodutibilidade do valor de cinza e o ruído do sistema IDA variam entre áreas com radiolucência diferente. Assim, atenção especial é necessária para o diagnóstico e proservação de lesões radiolucentes devido à interferência dos valores cinza relativamente alta. (AU).

Panorama situacional dos cursos de Habilitação em Odontologia Hospitalar: revisão integrativa / Situational overview of the courses of Qualification in Hospital Dentistry: integrative review

Cirurgiões-dentistas habilitados em práticas baseadas em evidências científicas e na aplicação de modelos de cuidados em saúde bucal bem-sucedidos trazem benefícios tanto à saúde individual quanto à coletiva. Este estudo traçou um panorama sobre cursos de Habilitação em Odontologia Hospitalar ofertados no Brasil após a regulamentação da Resolução 162/2015 pelo Conselho Federal de Odontologia (CFO), para auxiliar a escolha dos profissionais que pretendem se habilitar na área. O método de pesquisa foi a revisão integrativa da literatura, com análise quantitativa, exploratória e descritiva dos dados. O modelo de busca aplicado foi "habilitação em odontologia hospitalar", na base de dados Google, com uma única consulta em março de 2019. Dezessete (17) propostas foram encontradas. Seguiram para análise treze (13) propostas que informavam número de vagas ofertadas, periodicidade do curso, dias da semana em que ocorriam as atividades, carga horária total, conteúdo programático (teórico e prático) e local da prática. Falta de conteúdo programático (n=2) e de atualização (n=1) foram critérios de exclusão imediata. Na análise descritiva das propostas (n=10) houve exclusões por falta de definição da carga horária teórica e prática (n=4); informação sobre o conteúdo prático (n=5) e de identificação do local de desenvolvimento e carga horária mínima exigida para a prática. O estudo evidenciou que, à época da coleta de dados, apenas uma proposta atendia à legislação e à normativa exigidas pelo CFO (AU).

Dentists qualified on evidence-based practices and on the application of successful oral health care models are beneficial to individual and collective health. The current study presents an overview of Hospital Dentistry Qualification courses available in Brazil after the regulation of Resolution 162/2015 by the Conselho Federal de Odontologia (CFO - Brazil), which focuses on assisting the selection by professionals who intend to qualify in this field. Integrative literature review, with quantitative, exploratory and descriptive data analyses, was the research method adopted in the present study. The mesh "hospital dentistry qualification" was used in the single search conducted on Google database, in March 2019. Seventeen (17) proposals were found. Thirteen (13) proposals that included information about vacancies available for students, course periodicity, weekdays when the course took place, total workload, program content (theoretical and practical) and place of practice were selected for analysis. Lack of program content (n=2) and outdated information (n=1) were immediate exclusion criteria. The descriptive analysis applied to the proposals (n=10) has shown that courses were excluded due to lack of definition ofthe workload of theoretical and practical activities (n=4); as well as of information about the practical content of the course (n=5), the hospital where the practice would take place and the minimum workload required for the practice. One (01) qualification proposal was included in the research based on qualitative synthesis. The current study has shown that one proposal was in compliance with the legislation and regulations required by FCD, as well as that the presentation of the information available in the website about the proposal makes it hard for the target audience to make the option for the course that would best meet their needs (AU).

Dimensional Stability of Alginates Molds Tridimentionally Scanned / Estabilidade Dimensional de Moldes de Alginatos Escaneados Tridimensionalmente

Alginate is among the most used materials in dentistry to create teeth negative printing and reproduction. The goal of this study was to compare dimensional changes of alginate scanned impression materials. Thirty impressions of a standard typodont were performed using three types of alginate (Hydrogum 5; Jeltrate Plus and Avagel). The impressions were scanned by the scanner 3Shape R700T and scans were performed immediately after molding. The analysis of digital models were performed at OrthoAnalyzer ™ 3D software. Measurements were carried out in relation to the transverse dimension (intercanine, interpremolares and intermolar). Method error was evaluated through the Intraclass Correlation Coefficient (ICC) and Bland-Altman. One-way ANOVA, Dunnet Post-test were used to compare the different groups in relation to Typodont (gold standard) for the different outcome variables. The data were tabulated in Statistical Package for Social Sciences version 20.0 and Minitab 17.0 softwares to compare groups. The significance level was 5%. The posterior transverse variables (D1PM, D2PM and DM) presented a statistically significant difference regarding the gold standard (Typodont) for the plaster models performed after the Avagel molding. In the digital models performed just after molding, only in DM, the Avagel material group presented values statistically higher than the control group. The alginates Hydrogum 5 and Jeltrate Plus presented dimensions closer to the gold standard.(AU).

O alginato está entre os materiais de moldagem mais utilizados na Odontologia para criar impressão e reprodução negativa dos dentes. O objetivo desse trabalho foi comparar alterações transversais de três marcas comerciais de alginato (Hydrogum, Jeltrate e Avagel) em moldes de alginatos. Trinta moldes de um Typodont padrão foram realizados, utilizando três tipos de alginato (Hydrogum 5; Jeltrate Plus e Avagel). Os moldes foram escaneados por meio do scanner 3Shape R700T e os escaneamentos realizados logo após a moldagem e logo após a obtenção dos modelos de gesso. As análises dos modelos digitais foram realizadas no software OrthoAnalyzer™ 3D. Foram realizadas mensurações em relação à discrepância transversal (inter-caninos, inter-primeiro pré-molar, inter-segundo pré-molar e inter-molares). O erro do método foi avaliado por meio do Coeficiente de Correlação Intraclasse (CCI) e Bland-Altman. Utilizou-se Análise de Variância (one-way ANOVA, Pós-teste Dunnet) para comparação dos diferentes grupos em relação ao typodont (padrão-ouro) para as diferentes variáveis de desfecho. A análise estatística foi realizada nos programas Statistical Package for Social Sciences versão 20.0 e no programa Minitab 17.0 para comparação dos grupos. O nível de significância foi de 5%. As variáveis transversais posteriores (D1PM; D2PM e DM) apresentaram diferença estatisticamente significante em relação ao padrão-ouro (manequim) para os modelos de gesso realizados após a moldagem com Avagel. Nos modelos digitais realizados logo após a moldagem, apenas na DM, o grupo do material Avagel apresentou valores estatisticamente maiores do que o grupo controle. Os alginatos Hydrogum 5 e Jeltrate Plus apresentaram dimensões mais próximas do padrão-ouro.(AU).

Avaliação do Conhecimento do Protocolo de Higiene Bucal pela Equipe de Enfermagem da Unidade de Terapia Intensiva de Dois Hospitais em Londrina/PR / Evaluation of Knowledge of the Oral Hygiene Protocol by the Nursing Team of the Intensive Care Unit of Two Hospitals In Londrina/PR

Oral hygiene in the Intensive Care Unit - ICU is considered a basic and indispensable procedure whose goal is to maintain the patients' healthy oral conditions, reducing complications and contributing to their recovery. The objective of this study was to evaluate the knowledge on the oral hygiene protocol by the ICU nursing team of two hospitals in Londrina/PR. The sample of this study was composed by the nursing and nursing technicians team of the Intensive Care Unit of the Hospital A and Hospital B, regardless of gender or age, and considering who had worked at the ICU for at least three months. A self-administered, unidentified questionnaire was used to collect data. The analyzed variables were: profession, age, sex, working time and oral hygiene. More than 80% of the professionals were Nursing Technicians, with average age above 30, female and working in the ICU of the hospital for over 3.5 years. The results of this study demonstrate the lack of knowledge of the oral hygiene protocol by more than 30% of the Nursing staff in both hospitals. Based on the methodology and the results analysis, it can be concluded that the oral hygiene protocol is unknown by more than a third of the ICU Nursing team of both surveyed hospitals.(AU).

A higiene bucal em Unidade de Terapia Intensiva - UTI é considerada um procedimento básico e indispensável cujo objetivo é manter saudáveis as condições bucais dos pacientes, reduzindo agravos e contribuindo para sua recuperação. O objetivo deste estudo foi avaliar o conhecimento do protocolo de higiene bucal pela equipe de enfermagem da UTI de dois hospitais em Londrina/PR. A amostra deste estudo foi composta pela equipe de Enfermagem (Enfermeiros e Técnicos em Enfermagem) da Unidade de Terapia Intensiva do Hospital A e do Hospital B, independente do sexo e idade, e que trabalhavam na UTI, no mínimo, há três meses. Para a coleta de dados foi utilizado um questionário autoaplicável, não identificado. As variáveis analisadas foram: profissão, idade, sexo, tempo de trabalho e higiene bucal. Mais de 80% dos profissionais eram Técnicos em Enfermagem, com idade média acima dos 30 anos de idade, do sexo feminino e atuando na UTI do hospital, em média, acima de 3,5 anos. Os resultados deste estudo demonstram a falta de conhecimento do protocolo de higiene bucal, por mais de 30% da equipe de Enfermagem, em ambos os hospitais. Com base na metodologia e análise dos resultados, pode-se concluir que o protocolo de higiene bucal é desconhecido por mais de um terço da equipe de Enfermagem da UTI de ambos os hospitais pesquisados. (AU).

Health-related quality of life of patients with squamous cell carcinoma: a comparison according to tumor location.

The aim of this study was to evaluate the health-related quality of life (QOL) of patients with squamous cell carcinoma (SCC) according to tumor location. The sample consisted of 27 patients with primary SCC in the oral cavity (n = 15), pharynx (n = 7), and larynx (n = 5) who were undergoing cancer treatment at the Cancer Hospital of Londrina, regardless of age, sex, clinical stage, and type of antineoplastic treatment. Health-related QOL was evaluated using the 30-item Cancer-Quality of Life Questionnaire (QLQ-C30), the 35-item Head and Neck Cancer-Quality of Life Questionnaire (QLQ-HN35), and the University of Washington Quality of Life Questionnaire (UW-QOL). These questionnaires were administered individually to each patient before ambulatory care. Sociodemographic data (age and sex) and clinical data (T stage, tumor location, and type of antineoplastic treatment) were collected from the patients' medical records. Scores were compared according to tumor location using the chi-squared test and one-way analysis of variance (p < 0.05). No score differed significantly according to tumor location. It can be concluded that the health-related QOL of patients with SCC was not influenced by tumor location.

Dimensional changes of dental arches produced by fixed and removable palatal cribs: A prospective, randomized, controlled study.

OBJECTIVE: To evaluate the dimensional changes of dental arches on digital models of open bite treatment with fixed and removable palatal cribs. MATERIALS AND METHODS: The sample comprised 41 patients of both sexes who were white, aged 7-10 years, and who had mixed dentition, Angle Class I molar relationship, and a negative overbite of at least 1 mm. The sample was randomly divided into two groups: G1, fixed palatal crib; and G2, removable palatal crib. Cast models, obtained initially (T1) and after 1 year of treatment (T2), were scanned by a three-dimensional (3D) scanner, 3Shape R700, producing a 3D image. Measurements were performed by a calibrated examiner using OrthoAnalyzer™ 3D software. RESULTS: At T2-T1, differences were observed between the groups regarding vertical dentoalveolar development and overjet. There was more mandibular incisor extrusion for G1 (-1.66 mm) than for G2 (-0.54 mm). An overjet increase was observed in G1 (0.56 mm), in contrast to a reduction in G2 (-0.40 mm). There was a similar overbite increase for both groups (3.51 mm for fixed palatal crib and 3.88 mm for removable palatal crib). CONCLUSIONS: Both the treatment protocols are similarly effective for anterior open bite correction, providing an overbite increase with dentoalveolar arch changes, especially in the anterior region.

Health-related quality of life of patients with squamous cell carcinoma: a comparison according to tumor location

Abstract: The aim of this study was to evaluate the health-related quality of life (QOL) of patients with squamous cell carcinoma (SCC) according to tumor location. The sample consisted of 27 patients with primary SCC in the oral cavity (n = 15), pharynx (n = 7), and larynx (n = 5) who were undergoing cancer treatment at the Cancer Hospital of Londrina, regardless of age, sex, clinical stage, and type of antineoplastic treatment. Health-related QOL was evaluated using the 30-item Cancer-Quality of Life Questionnaire (QLQ-C30), the 35-item Head and Neck Cancer-Quality of Life Questionnaire (QLQ-HN35), and the University of Washington Quality of Life Questionnaire (UW-QOL). These questionnaires were administered individually to each patient before ambulatory care. Sociodemographic data (age and sex) and clinical data (T stage, tumor location, and type of antineoplastic treatment) were collected from the patients' medical records. Scores were compared according to tumor location using the chi-squared test and one-way analysis of variance (p < 0.05). No score differed significantly according to tumor location. It can be concluded that the health-related QOL of patients with SCC was not influenced by tumor location.

Analysis of linear measurements on 3D surface models using CBCT data segmentation obtained by automatic standard pre-set thresholds in two segmentation software programs: an in vitro study.

OBJECTIVE: The aim of this in vitro study was to evaluate the reliability and accuracy of linear measurements on three-dimensional (3D) surface models obtained by standard pre-set thresholds in two segmentation software programs. MATERIALS AND METHODS: Ten mandibles with 17 silica markers were scanned for 0.3-mm voxels in the i-CAT Classic (Imaging Sciences International, Hatfield, PA, USA). Twenty linear measurements were carried out by two observers two times on the 3D surface models: the Dolphin Imaging 11.5 (Dolphin Imaging & Management Solutions, Chatsworth, CA, USA), using two filters(Translucent and Solid-1), and in the InVesalius 3.0.0 (Centre for Information Technology Renato Archer, Campinas, SP, Brazil). The physical measurements were made by another observer two times using a digital caliper on the dry mandibles. RESULTS: Excellent intra- and inter-observer reliability for the markers, physical measurements, and 3D surface models were found (intra-class correlation coefficient (ICC) and Pearson's r ≥ 0.91). The linear measurements on 3D surface models by Dolphin and InVesalius software programs were accurate (Dolphin Solid-1 > InVesalius > Dolphin Translucent). The highest absolute and percentage errors were obtained for the variable R1-R1 (1.37 mm) and MF-AC (2.53 %) in the Dolphin Translucent and InVesalius software, respectively. CONCLUSION: Linear measurements on 3D surface models obtained by standard pre-set thresholds in the Dolphin and InVesalius software programs are reliable and accurate compared with physical measurements. CLINICAL RELEVANCE: Studies that evaluate the reliability and accuracy of the 3D models are necessary to ensure error predictability and to establish diagnosis, treatment plan, and prognosis in a more realistic way.

Analysis of the reproducibility of the gray values and noise of a direct digital radiography system.

The aim of this study was to evaluate the reproducibility of the gray values and noise of a direct digital radiography system (Visualix eHD) for various exposure times and analyzed regions. To obtain radiographic images in a standardized manner, the digital sensor of the system and a stepwedge were positioned in a phantom at a focus-film distance of 30 cm in a dental device at 70 kV, 7 mA and 2.2 mm filtration. Ten consecutive repetitions of X-ray imaging were performed at each exposure time (0.05, 0.07, 0.09 and 0.13 s). Gray values were analyzed using ImageJ software in five regions of interest (ROIs): alveolar bone (AB), soft tissue (ST) and three steps of the stepwedge (S1, S2 and S3). The results showed that both the variability of the gray values and the noise were statistically greater (p < 0.05) in the most radiolucent region (ST). Only the noise was affected by the exposure time. In conclusion, the reproducibility of the gray values and the noise of the Visualix eHD system can vary in specific areas with different radiolucency.

Comparison between 3D volumetric rendering and multiplanar slices on the reliability of linear measurements on CBCT images: an in vitro study

OBJECTIVE: The purpose of this study was to determine the accuracy and reliability of two methods of measurements of linear distances (multiplanar 2D and tridimensional reconstruction 3D) obtained from cone-beam computed tomography (CBCT) with different voxel sizes. MATERIAL AND METHODS: Ten dry human mandibles were scanned at voxel sizes of 0.2 and 0.4 mm. Craniometric anatomical landmarks were identified twice by two independent operators on the multiplanar reconstructed and on volume rendering images that were generated by the software Dolphin®. Subsequently, physical measurements were performed using a digital caliper. Analysis of variance (ANOVA), intraclass correlation coefficient (ICC) and Bland-Altman were used for evaluating accuracy and reliability (p<0.05). RESULTS: Excellent intraobserver reliability and good to high precision interobserver reliability values were found for linear measurements from CBCT 3D and multiplanar images. Measurements performed on multiplanar reconstructed images were more accurate than measurements in volume rendering compared with the gold standard. No statistically significant difference was found between voxel protocols, independently of the measurement method. CONCLUSIONS: Linear measurements on multiplanar images of 0.2 and 0.4 voxel are reliable and accurate when compared with direct caliper measurements. Caution should be taken in the volume rendering measurements, because the measurements were reliable, but not accurate for all variables. An increased voxel resolution did not result in greater accuracy of mandible measurements and would potentially provide increased patient radiation exposure. .

Can bone thickness and inter-radicular space affect miniscrew placement in posterior mandibular sites?

PURPOSE: The proper angle of miniscrew insertion is important for cortical anchorage, patient safety, and biomechanical control. The purposes of this study are to report the alveolar process thickness and inter-radicular space in the posterior region of the mandible, to assess the impact of different miniscrew insertion angle protocols, and to identify differences between the genders or types of malocclusion. MATERIALS AND METHODS: In this retrospective study, 100 individuals were selected for orthodontic treatment at a radiology clinic. Cone-beam computed tomography data were imported into 3-dimensional software. The predictor variable was the location in the mandible and insertion angle. The demographic variables collected included age, gender, and malocclusion (Angle Classes I and II). The primary outcome variables were bone thickness and inter-radicular space. The inter-radicular spaces were evaluated 5 mm from the cement-enamel junction. The bone thicknesses were taken at 45°, 60°, and 90° in relation to the alveolar ridge, simulating a miniscrew insertion. These factors were evaluated for sexual dimorphism and malocclusion (Angle Classes I and II). Sexual dimorphism and malocclusion were evaluated with t tests. To compare the inter-radicular space and the thickness of bone between areas, an analysis of variance for repeated measures was used. RESULTS: The sample was composed of 100 patients with a mean age of 17.4 ± 6.74 years. There were 61 female and 39 male patients and 60 Class I and 40 Class II molar relationships. The inter-radicular space ranged from 2.46 to 3.31 mm, and alveolar bone thickness ranged from 8.01 to 13.77 mm. The thickness tended to decrease with the increase in insertion angle from 45° to 90°. No significant differences between the genders or types of malocclusion were found. CONCLUSIONS: The results of this study suggest that the safest areas for the placement of miniscrews are between the first and second premolars and between the first and second molars, regardless of the angle of insertion.

Comparison between 3D volumetric rendering and multiplanar slices on the reliability of linear measurements on CBCT images: an in vitro study.

OBJECTIVE: The purpose of this study was to determine the accuracy and reliability of two methods of measurements of linear distances (multiplanar 2D and tridimensional reconstruction 3D) obtained from cone-beam computed tomography (CBCT) with different voxel sizes. MATERIAL AND METHODS: Ten dry human mandibles were scanned at voxel sizes of 0.2 and 0.4 mm. Craniometric anatomical landmarks were identified twice by two independent operators on the multiplanar reconstructed and on volume rendering images that were generated by the software Dolphin®. Subsequently, physical measurements were performed using a digital caliper. Analysis of variance (ANOVA), intraclass correlation coefficient (ICC) and Bland-Altman were used for evaluating accuracy and reliability (p<0.05). RESULTS: Excellent intraobserver reliability and good to high precision interobserver reliability values were found for linear measurements from CBCT 3D and multiplanar images. Measurements performed on multiplanar reconstructed images were more accurate than measurements in volume rendering compared with the gold standard. No statistically significant difference was found between voxel protocols, independently of the measurement method. CONCLUSIONS: Linear measurements on multiplanar images of 0.2 and 0.4 voxel are reliable and accurate when compared with direct caliper measurements. Caution should be taken in the volume rendering measurements, because the measurements were reliable, but not accurate for all variables. An increased voxel resolution did not result in greater accuracy of mandible measurements and would potentially provide increased patient radiation exposure.

Analysis of the reproducibility of the gray values and noise of a direct digital radiography system

The aim of this study was to evaluate the reproducibility of the gray values and noise of a direct digital radiography system (Visualix eHD) for various exposure times and analyzed regions. To obtain radiographic images in a standardized manner, the digital sensor of the system and a stepwedge were positioned in a phantom at a focus-film distance of 30 cm in a dental device at 70 kV, 7 mA and 2.2 mm filtration. Ten consecutive repetitions of X-ray imaging were performed at each exposure time (0.05, 0.07, 0.09 and 0.13 s). Gray values were analyzed using ImageJ software in five regions of interest (ROIs): alveolar bone (AB), soft tissue (ST) and three steps of the stepwedge (S1, S2 and S3). The results showed that both the variability of the gray values and the noise were statistically greater (p < 0.05) in the most radiolucent region (ST). Only the noise was affected by the exposure time. In conclusion, the reproducibility of the gray values and the noise of the Visualix eHD system can vary in specific areas with different radiolucency.

Pixel value analysis for detection of simulated early external root resorption.

The aim of this study was to determine the efficacy of pixel value analysis using images generated by the Digora™ and Visualix™ systems for the early detection of external root resorption (ERR). Thirty extracted human lower incisors were radiographed using the Digora and Visualix systems; then, ERR was induced by immersing the teeth in 6 mol L-1 of hydrochloric acid for different periods of time (10, 30 and 60 minutes). ERR was confirmed by calcium quantification with an atomic absorption spectrophotometer. One digital image was acquired per time period at 70 kVp, 7 mA, 2.2 mm filtration, focus-film distance of 30 cm, and with exposure times of 0.09 s in the Digora system and 0.05 s in Visualix system. The region of interest was defined using ImageJ software. Statistical analysis was performed using ANOVA and Pearson's correlation (p < 0.05). There was no statistically significant difference between the time for ERR induction and the pixel values with either system. A positive correlation between the time of ERR induction and the calcium concentration was observed (r = 0.8892; p < 0.001). In conclusion, independent of the site of ERR induction and the digital system, pixel value analysis was not effective for ERR detection.