Cláudio Rodrigues Leles

Accuracy of Cone Beam Computed Tomography and Panoramic and Periapical Radiography for Detection of Apical Periodontitis

The aim of this study was to evaluate the accuracy of imaging methods for detection of apical periodontitis (AP). Imaging records from a consecutive sample of 888 imaging exams of patients with endodontic infection (1508 teeth), including cone beam computed tomography (CBCT) and panoramic and periapical radiographs, were selected. Sensitivity, specificity, predictive values, and accuracy of periapical and panoramic radiographs were calculated. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic accuracy of the panoramic and periapical images. Prevalence of AP was significantly higher with CBCT. Overall sensitivity was 0.55 and 0.28 for periapical and panoramic radiographs, respectively. ROC curves and area under curve (AUC) with periapical radiography showed a high accuracy for the cutoff value of 5 for both periapical (AUC, 0.90) and panoramic (AUC, 0.84) radiographs. AP was correctly identified with conventional methods when showed advanced status. CBCT was proved to be accurate to identify AP.

Assessments of trabecular bone density at implant sites on CT images.

OBJECTIVES To evaluate the association between trabecular bone density measurements of potential implant sites made on axial DICOM images (DentaCT software) and on the same images with eFilm workstation, to correlate bone densities in Hounsfield units (HU) with subjective classification, and to establish a quantitative scale for each bone quality class. STUDY DESIGN Twenty-seven maxillary and 27 mandibular computed tomographic (CT) examinations of 75 potential implant sites were selected. Trabecular bone density was evaluated with DentaCT and eFilm. Bone quality was subjectively evaluated by 2 examiners. Descriptive statistics, between- and within-group comparison, correlation analysis, and Bland-Altman plot were used for data analysis. RESULTS DentaCT measurements were higher than eFilm (P < .001). Bone type 2 was the most prevalent, and bone density was significantly reduced from bone types 1 to 4. Quantitative parameters ranged as follows: bone type 4 <200 HU, bone types 2 and 3 >200 to <400 HU, and bone type 1 >400 HU. CONCLUSION Different qualities of bone can be found in any of the anatomical regions studied (anterior and posterior sites of maxilla and mandible), which confirms the importance of a site-specific bone tissue evaluation prior to implant installation.

Efficacy of sodium hypochlorite and chlorhexidine against Enterococcus faecalis: a systematic review

The efficacy of the sodium hypochlorite (NaOCl) and chlorhexidine (CHX) on Enterococcus faecalis was evaluated by systematic review and meta-analysis. The search strategies included search in electronic biomedical journal databases (MEDLINE, EMBASE, CENTRAL) and handsearching records, using different matches of keywords for NaOCl, CHX and Enterococcus faecalis. From 41 in vivo studies, 5 studies met the inclusion criteria. In a sample containing 159 teeth, E. faecalis was detected initially in 16 (10%) teeth by polymerase chain reaction (PCR) and 42 (26.4%) teeth by microbial culture techniques. After root canal disinfection, this species was observed in 11 (6.9%) teeth by PCR and 12 (7.5%) teeth by culture. Risk differences of included studies were combined as generic inverse variance data type (Review Manager Version 5.0 – Cochrane Collaboration, http://www.cc-ims.net, accessed 15 May 2008), taking into account the separate tracking of positive and negative cultures/PCR. The level of statistical significance was set at p<0.05. In conclusion, NaOCl or CHX showed low ability to eliminate E. faecalis when evaluated by either PCR or culture techniques.

Occurrence of maxillary sinus abnormalities detected by cone beam CT in asymptomatic patients

BackgroundAlthough cone beam computed tomography (CBCT) images of the maxillofacial region allow the inspection of the entire volume of the maxillary sinus (MS), identifying anatomic variations and abnormalities in the image volume, this is frequently neglected by oral radiologists when interpreting images of areas at a distance from the dentoalveolar region, such as the full anatomical aspect of the MS. The aim of this study was to investigate maxillary sinus abnormalities in asymptomatic patients by using CBCT.Methods1113 CBCT were evaluated by two examiners and identification of abnormalities, the presence of periapical lesions and proximity to the lower sinus wall were recorded. Data were analyzed using descriptive statistics, chi-square tests and Kappa statistics.ResultsAbnormalities were diagnosed in 68.2% of cases (kappa = 0.83). There was a significant difference between genders (p < 0.001) and there was no difference in age groups. Mucosal thickening was the most prevalent abnormality (66%), followed by retention cysts (10.1%) and opacification (7.8%). No association was observed between the proximity of periapical lesions and the presence and type of inflammatory abnormalities (p = 0.124).ConclusionsAbnormalities in maxillary sinus emphasizes how important it is for the dentomaxillofacial radiologist to undertake an interpretation of the whole volume of CBCT images.

Differential infiltration of CD8+ and NK cells in lip and oral cavity squamous cell carcinoma.

BACKGROUND CD8+ and natural killer (NK) cells have been considered the most effective cells in the combat of cancer, contributing to better prognosis and longer survival. METHODS The aim of this study was to evaluate the population of CD8+ and NK cells, by immunohistochemistry, in samples of oral cavity squamous cell carcinoma (OCSCC) and lip squamous cell carcinoma (LSCC), leukoplakia, actinic cheilitis, and healthy oral mucosa (control). The relationship of CD8+ and NK cells with survival data, lymph node metastasis, tumor size, and proliferative index was also evaluated. RESULTS The number of peritumoral and intratumoral CD8+ and NK cells was significantly higher in LSCC, when compared with control, pre-malignant lesions, and OCSCC. A higher proportion of peritumoral CD8+ cells demonstrated correlation with a lower neoplastic proliferative index. Moreover, patients with OCSCC with a high density of peritumoral CD8+ cells showed a tendency towards a longer survival time. CONCLUSIONS The differential CD8+ and NK cells infiltration in oral SCC might reflect a distinctive tumor microenvironment with a favorable local cytotoxic immune response against neoplastic cells.

Condição de saúde bucal em escolares de 12 anos de escolas públicas e privadas de Goiânia, Brasil

OBJETIVO: Comparar os alunos de 12 anos das escolas publicas e privadas de Goiânia, Goias, quanto a prevalencia de carie, condicao periodontal, anomalia dentofacial e fluorose. METODOS: Em 2003, o Projeto Condicoes de Saude Bucal da Populacao Brasileira 2002-2003 (SB Brasil) foi ampliado para Goiânia na forma de um estudo transversal, descrito neste trabalho. A amostra foi constituida por 1 947 escolares de 12 anos frequentando escolas da zona urbana do Municipio: 1 790 (91,9%) eram de escolas publicas e 157 (8,1%) de escolas privadas. Atraves de exame clinico, foram coletados dados sobre as seguintes condicoes bucais: carie dentaria (indice de dentes cariados, perdidos e obturado, CPOD), condicao periodontal (indice periodontal comunitario, CPI), anormalidade dento-facial (indice de estetica dental, DAI) e fluorose dentaria (indice de Dean). Para comparacao entre os grupos foram utilizados os testes do qui-quadrado e U de Mann Whitney. RESULTADOS: Houve diferenca entre os tipos de escola para todas as variaveis investigadas. Os escolares de instituicoes publicas apresentaram indices mais elevados de carie, condicao periodontal e anomalia dentofacial do que aqueles de escolas privadas (P < 0,05). Os escolares de instituicoes privadas apresentaram maior prevalencia de fluorose (P < 0,05). CONCLUSOES: O tipo de escola foi associado a condicao de saude bucal dos escolares pesquisados. Sao recomendados investimentos em acoes e servicos que busquem minimizar tais desigualdades e seus efeitos como parte das politicas de saude bucal.

Bone tissue microarchitectural characteristics at dental implant sites. Part 1: Identification of clinical‐related parameters

OBJECTIVE To identify the characteristics of bone tissue microarchitecture by microCT at dental implant bone sites, describing them in terms of clinical parameters. MATERIAL AND METHODS Forty-six bone implant sites of the maxilla and mandible from 32 volunteers were evaluated by conventional radiographs and CT scans. During the installation of each implant, bone biopsies were removed using a trephine bur at the first drilling to prepare the socket implant. Each sample was evaluated by microCT and dimensional parameters measured. RESULTS Factor analysis summarized the microparameters into four components, which accounted for 92.8% of the total variance. The identified factors were (1) architecture - variables affecting 3D trabecular bone configuration and organization, (2) density - variables relating to surface/volume ratios and volume/volume ratios, (3) bulk - variables relating to the amount of bone and (4) spacing - variable related to the distance between trabeculae and the quantity and organization of marrow spaces. CONCLUSION These four summarized factors correspond to clinical and radiographically recognizable parameters used for routine bone quality evaluation for implant treatment planning, which can potentially influence the primary stability of dental implants. The understanding of factors related to bone microarchitecture might reveal important aspects of its mechanical properties, essential for implant success.

Involvement of CXCL12 and CXCR4 in Lymph Node Metastases and Development of Oral Squamous Cell Carcinomas

The chemokine stromal cell-derived factor (SDF-1/CXCL12) and its specific receptor, CXCR4, have been implicated in the regulation of tumor growth and organ-specific spread. The aim of this study was to determine the expression of CXCL12 and CXCR4 in samples obtained from primary squamous cell carcinoma (SCC) of the oral cavity (OCSCC) and of the lip (LSCC) and in metastatic and non-metastatic lymph node tissues. The relationship of CXCL12/CXCR4 with clinical and microscopic parameters was also evaluated. The analysis of mRNA expression revealed a higher expression of CXCR4 in oral SCC compared with healthy oral mucosa (p = 0.006). The density of CXCR4+ cells was higher in parenchyma of OCSCC with lymph node metastases than in LSCC. With regard to the stroma, OCSCC showed a greater CXCR4+ and CXCL12+ cell percentage in relation to LSCC. Furthermore, the density of CXCL12+ and CXCR4+ nodal cells was higher in metastatic than non-metastatic lymph nodes in the same patients. Considering clinical and microscopic parameters, we found a positive association between the percentages of CXCL12+ and CXCR4+ stromal cells and the tumor proliferation index. Our findings suggest that the CXCL12/CXCR4 system may play a role in tumor cell spread to lymph nodes and also in neoplastic development.

Effect of intraoral low-level laser therapy on quality of life of patients with head and neck cancer undergoing radiotherapy.

Low‐level laser therapy has been used to reduce complications of head and neck cancer treatment. The aim was to assess the impact of laser in the quality of life (QOL) of patients receiving radiotherapy.

Effect of low level laser therapy in the reduction of oral complications in patients with cancer of the head and neck submitted to radiotherapy.

The aim of this study was to assess the effect of low level laser therapy on reducing the occurrence and severity of oral complications in patients with head and neck cancer undergoing radiotherapy. Sixty head and neck cancer outpatients from a cancer hospital receiving radiotherapy were selected and randomly assigned into two groups. The laser group was irradiated with an InGaAlP laser and the control received sham laser. The assessment of complications (oral mucositis, pain) was carried out one week after starting radiotherapy, and at the fifteenth and thirtieth sessions of radiotherapy. All patients from both groups showed some degree of oral mucositis. Better outcomes were observed in the laser group when compared with the control in the follow-up sessions, indicating lower degrees of oral mucositis, pain and higher salivary flow (p < .05). These findings support the use of laser therapy as an adjuvant treatment for the control of oral complications.