Cone beam computed tomography (CBCT) referrals in paediatric patients: A 24-month retrospective study in two radiological centers in Campinas, Brazil.

PURPOSE: To evaluate the CBCT referrals in paediatric patients over a 24-month period. METHODS: A retrospective study was conducted in two radiological centers in Campinas, Brazil. Patients were divided into three age groups: G1: age under 10 years, G2: age between 10 and 12 years, and G3: age over 12 years. The following data were collected: patients' age and sex, localisation, reasons for referral and dental specialty responsible for the request of CBCT exams. RESULTS: Data from 367 patients were assessed. CBCT was used more frequently in the Group 3 (58.9%). There was significant association between the region of the exam and age group (P < 0.05), with a higher percentage of exams in the maxilla for the age over 12 years (35.6%) than that of up to 10 years (50.9%) and between 10 and 12 years (51.1%). Alterations were observed in 79.3% of the exams and 47.4% showed impacted teeth with significant association with the increase in age group (P < 0.05). Of the total number of exams, (55.3%) were requested in Orthodontics followed by Oral Surgery (30.0%) and Paediatric Dentistry (9.5%). CONCLUSIONS: It can be concluded that CBCT exams were indicated frequently for the age over 12 years. The presence of impacted teeth represented the main reason for referrals and Orthodontics was the dental specialty that indicated CBCT with higher frequency.

Alveolar antral artery in edentulous patients and their visualization through cone beam computed tomography.

OBJECTIVE OF THE STUDY: The aim of this study was to assess the anatomical features of the alveolar antral artery (AAA) in edentulous patients using cone beam computed tomography (CBCT). PATIENTS: The sample consisted of 191 CBCT scans of maxillary sinuses (n=382) of male (n=59) and female (n=132) edentulous patients (age: 38-89 years). MATERIAL AND METHODS: The images were analyzed in Dolphin™ 11.9 software. Visualization, location, and diameter of the AAA was registered. RESULTS: AAA was present in 88.5% of the assessed maxillary sinuses. Bilateral visualization was predominant 77% (P<0.0001). The mean vertical distance from the most anterior part of the AAA to the sinus floor was 7.9±6mm in female patients (both sides) and 12±7.22mm on the right side and 10.9±6.86mm on the left side in males. The mean diameter of the AAA was 1.2±0.7mm on both sides in females. In males, the diameter was significantly (P<0.05) larger: 1.5±0.62mm on the right side and 1.4±0.69 on the left side in females. CONCLUSION: The AAA had a higher visualization rate, better visualization, and larger diameter when it was present bilaterally in male and female patients.

Marginal bone loss in the second molar related to impacted mandibular third molars: comparison between panoramic images and cone beam computed tomography.

BACKGROUND: Deciding whether or not to extract third molars remains a controversial situation in dental practice. Image exams support this decision by enabling a close view of the third molar, its adjacent bone and its relationship with the second molar. This study aimed to assess and compare second molar bone loss adjacent to impacted mandibular third molar in panoramic radiographs (PAN) and cone beam computed tomography (CBCT) scans. MATERIAL AND METHODS: A sample of 70 patients was selected (n=124 teeth). Each patient had a set of a panoramic radiograph and CBCT scans consecutively taken for dental treatment purposes. In PAN and CBCT, mandibular third molars were classified based on their position and bone loss of the adjacent second molar. Agreement between PAN and CBCT scans was assessed and quantified. RESULTS: Outcomes of bone loss assessment were different between PAN and CBCT scans (p<0.05). Bone loss was found in 62.9% of the PAN, while in CBCT scans it was found in 80%. In particular, nearly 29% (n=27) of the teeth that were classified without bone loss in PAN were classified with bone loss in CBCT scans. Mesioangular and horizontal third molars had a statistically significant association with bone loss of the adjacent second molars (p<0.05). In general, PAN underestimated the severity of bone loss compared to CBCT scans (p<0.05). CONCLUSIONS: Diagnosing second molar bone loss due to impaction of adjacent third molar in PAN may be challenging because of false negatives. Impacted third molars justify preoperative CBCT scans if second molar bone loss needs to be precisely assessed for a more detailed and reliable treatment plan.

Evaluation of the accuracy of linear measurements on multi-slice and cone beam computed tomography scans to detect the mandibular canal during bilateral sagittal split osteotomy of the mandible.

The aim of this study was to compare the accuracy of linear measurements of the distance between the mandibular cortical bone and the mandibular canal using 64-detector multi-slice computed tomography (MSCT) and cone beam computed tomography (CBCT). It was sought to evaluate the reliability of these examinations in detecting the mandibular canal for use in bilateral sagittal split osteotomy (BSSO) planning. Eight dry human mandibles were studied. Three sites, corresponding to the lingula, the angle, and the body of the mandible, were selected. After the CT scans had been obtained, the mandibles were sectioned and the bone segments measured to obtain the actual measurements. On analysis, no statistically significant difference was found between the measurements obtained through MSCT and CBCT, or when comparing the measurements from these scans with the actual measurements. It is concluded that the images obtained by CT scan, both 64-detector multi-slice and cone beam, can be used to obtain accurate linear measurements to locate the mandibular canal for preoperative planning of BSSO. The ability to correctly locate the mandibular canal during BSSO will reduce the occurrence of neurosensory disturbances in the postoperative period.

Accuracy assessment of the axial images obtained from cone beam computed tomography.

OBJECTIVE: The aim of this study was to evaluate accuracy of linear measurements assessed from axial tomograms and the influence of the use of different protocols in two cone beam CT (CBCT) units. METHODS: A cylinder object consisting of Nylon® (Day Brazil, Sao Paulo, Brazil) with radiopaque markers was radiographically examined applying different protocols from NewTom 3G(TM) (Quantitative Radiology s.r.l, Verona, Veneto, Italy) and i-CAT(TM) (Imaging Sciences International, Hatfield, PA) units. Horizontal (A-B) and vertical (C-D) distances were assessed from axial tomograms and measured using a digital calliper that provided the gold standard for actual values. RESULTS: There were differences when considering acquisition protocols to each CBCT unit. Concerning all analysed protocols from i-CAT(TM) and Newtom 3G(TM), both A-B and C-D distances presented underestimated values. Measurements of the axial images obtained from NewTom 3G(TM) (6 inch 0.16 mm and 9 inch 0.25 mm) were similar to the ones obtained from i-CAT(TM) (13 cm 20 s 0.3 mm, 13 cm 20 s 0.4 mm and 13 cm 40 s 0.25 mm). CONCLUSION: The use of different protocols from CBCT machines influences linear measurements assessed from axial images. Linear distances were underestimated in both equipments. Our findings suggest that the best protocol for the i-CAT(TM) is 13 cm 20 s 0.3 mm and for the NewTom 3G(TM), the use of 6 inch or 9 inch is recommended.

Actinic cheilitis among agricultural workers in Campinas, Brazil.

OBJECTIVE: To assess the prevalence of Actinic Cheilitis (AC) among agricultural workers and analyze its risk factors. DESIGN: A cross sectional epidemiological study. A lip lesion was defined as an abnormal change on the lip mucosa surface, such as erythematous pigmented, ulcerative or swelling (Cataldo and Doku, 1981). Data were gathered according to age group, gender, ethnicity-time and frequency of occupational sunlight exposure, smoking habits, drinking habits and socio-economic status. SETTING: Sugar-cane plantation farms in Brazil. PARTICIPANTS: Full-time workers of both genders employed at sugar-cane plantation farms for at least six months. OUTCOME MEASURES: Correlations between AC prevalence, demographic and socioeconomic risk factors. RESULTS: 202 people were examined and the prevalence of AC was 39.6%. Results revealed that being black (0.15-0.88- 95% CI; OR = 0.36; p = 0.025) or mulatto (0.21-0.82- 95% CI; OR = 0.42; p =0.011) decreased the risk for AC, while age and gender sex had no effect. In relation to socioeconomic variables, formal education and more than four years of education (0.07-0.68- 95% CI; OR = 0.22; p = 0.009) decreased the risk for AC. Moreover, drinking alcohol was a risk for AC (1.05-3.37- 95% CI; OR = 1.88; p = 0.034), while tobacco smoking was not (0.60-2.02- 95% CI; OR = 1.10; p = 0.763). CONCLUSIONS: The prevalence of AC is high in agricultural workers who were fairskinned, had low education and high alcohol intake. Prevention and early diagnosis are required for workers exposed to sunlight.

Peroxiredoxin I is differentially expressed in multiple myelomas and in plasmablastic lymphomas.

BACKGROUND: Plasmablastic lymphoma (PBL) and multiple myeloma (MM) are B cell-derived malignancies that share many morphologic and immunophenotypic traits, making the differential diagnosis particularly complicated. We have recently demonstrated that peroxiredoxin I (PrdxI) is expressed in plasma cells but not in B lymphocytes, suggesting that its expression is development-associated. AIM: To analyze PrdxI expression in PBL and in MM in order to study its utilization as an additional diagnostic molecular tool. METHODS AND RESULTS: Eight cases of PBL and nine of MM were studied by immunohistochemistry. We have demonstrated that PrdxI expression is closely connected with the immunoglobulin production capacity of the cells, which means high in MM, but absent in PBL cases, except one, wherein few cells were stained. CONCLUSIONS: We hypothesize PrdxI as a component of the unfolded protein response (UPR), an adaptive pathway essential for plasma cell differentiation. As we have not detected immunoglobulin in our PBL cases, we suggest that UPR was not activated in the cells, accounting for the impediment of the developmental process, and for the inhibition of PrdxI expression observed. PrdxI could be considered an additional plasma cell functional marker and could also be speculated as a therapeutic target in the treatment of MM.