Resumo O objetivo deste estudo foi avaliar a estabilidade de implante e a microarquitetura óssea em duas técnicas de fresagem, comparando a técnica convencional (CT) e a osseodensificação (OD) (Versah Burs - Jackson - Mississippi - EUA). O torque de inserção do implante (IT), quociente de estabilidade primária (ISQ) e a estrutura trabecular peri-implantar foram avaliados em fragmentos ósseos obtidos de tíbia de porco (n=12), divididos entre CT (n=6) e OD (n=6). Após o procedimento de fresagem, foram instalados implantes (3,5x8,5 mm, Epikut - SIN - São Paulo - Brasil). O IT e o ISQ foram aferidos por meio de um torquimetro digital e análise de frequência de ressonância. Em seguida, os fragmentos ósseos contendo os implantes foram removidos com trefina e analisados por microtomografia computadorizada (µCT, 8,0 µm). A comparação entre os grupos foi realizada por meio do teste-t não-pareado (α=0.05). Os resultados revelaram que a OD promove maior torque de inserção (CT: 7,67 ± 2,44º Ncm; OD: 19,78 ± 5,26 Ncm) (p=0,0005), embora a estabilidade primária não tenha sido diferente (CT: 61.33 ± 4.66; OD:63.25 ± 4.58) (p=0,48). Houve um aumento significativo no volume ósseo peri-implantar (CT: 23,17±3,39 mm3; OD: 32,01±5,75 mm3) (p=0,0089) e parâmetros trabeculares: separação (CT: 0,4357 ± 0,03 mm; OD: 0,3865 ± 0,04 mm) (p=0,0449), número (CT: 1,626 ± 0,18 1/mm; OD: 1,946 ± 0,13 1/mm) (p=0,007) e espessura (CT: 0,1130 ± 0,009 mm; OD: 0,1328 ± 0,015 mm) (p=0,02) O índice de modelo estrutural (SMI) não demostrou diferença estatisticamente significativa (p=0.1228). Concluindo, OD apresenta maiores valores de torque de inserção e promove mudanças benéficas na microarquitetura óssea em comparação com a TC, revelando maior volume ósseo peri-implantar. fresagem (CT (OD Versah EUA. EUA . EUA) IT, , (IT) (ISQ periimplantar peri implantar n=12, n12 n n=12 12 (n=12) n=6 n6 6 (n=6 n=6. 3,5x8,5 35x85 x 3 5x8 5 (3,5x8, mm Brasil. Brasil Brasil) ressonância seguida µCT, µCT (µCT 80 8 0 8, µm. µm µm) testet teste t nãopareado pareado α=0.05. α005 α α=0.05 05 (α=0.05) 767 7 67 7,6 244º º 2 44º Ncm 1978 19 78 19,7 526 26 5,2 p=0,0005, p00005 p p=0,0005 0005 (p=0,0005) 6133 61 33 61.3 4.66 466 4 66 OD63.25 OD6325 63.25 63 25 OD:63.2 4.58 458 58 p=0,48. p048 p=0,48 48 (p=0,48) 2317339 23 17 39 23,17±3,3 mm3 3201575 32 01 75 32,01±5,7 p=0,0089 p00089 0089 (p=0,0089 trabeculares 04357 4357 0,435 003 03 0,0 03865 3865 0,386 004 04 p=0,0449, p00449 p=0,0449 0449 (p=0,0449) 1626 1 626 1,62 018 18 0,1 1/mm 1mm 1946 946 1,94 013 13 p=0,007 p0007 007 (p=0,007 01130 1130 0,113 0009 009 0,00 01328 1328 0,132 0015 015 0,01 p=0,02 p002 02 (p=0,02 SMI (SMI p=0.1228. p01228 p=0.1228 1228 (p=0.1228) Concluindo TC periimplantar. implantar. (IT n1 n=1 (n=12 n= (n= 3,5x8, 35x8 5x (3,5x8 α00 α=0.0 (α=0.05 76 7, 197 19, 52 5, p0000 p=0,000 000 (p=0,0005 613 61. 4.6 46 OD63 OD63.2 OD632 6325 63.2 OD:63. 4.5 45 p04 p=0,4 (p=0,48 231733 23,17±3, 320157 32,01±5, p=0,008 p0008 008 (p=0,008 0435 435 0,43 00 0, 0386 386 0,38 p0044 p=0,044 044 (p=0,0449 162 62 1,6 194 94 1,9 p=0,00 p000 (p=0,00 0113 113 0,11 0132 132 001 p=0,0 p00 (p=0,0 p0122 p=0.122 122 (p=0.1228 (n=1 (n 3,5x8 35x (3,5x α0 α=0. (α=0.0 (p=0,000 4. OD6 OD63. 632 63. OD:63 p0 p=0, (p=0,4 23173 23,17±3 32015 32,01±5 043 43 0,4 038 38 0,3 p004 p=0,04 (p=0,044 16 1, 9 011 11 (p=0, p012 p=0.12 (p=0.122 3,5x α=0 (α=0. OD:6 p=0 2317 23,17± 3201 32,01± (p=0,04 (p=0 p01 p=0.1 (p=0.12 α= (α=0 p= 231 23,17 320 32,01 (p= p=0. (p=0.1 (α= 23,1 32,0 (p (p=0. (α 23, 32,

Abstract: The aim was to evaluate primary implant stability and bone microarchitecture in two drilling situations, by comparing the conventional technique (CT) and osseodensification (OD) (Versah Burs - Jackson - Mississippi - USA). The implant insertion torque (IT), implant stability quotient (ISQ), and the peri-implant trabecular microstructure were assessed on bone fragments obtained from pig’s tibia (n=12), divided between CT (n=6) and OD (n=6). After the drilling procedure, the implants were installed (3.5x8.5 mm, Epikut - SIN - São Paulo - Brazil). The IT and ISQ were measured using a digital torque wrench and resonance frequency analysis. Then, the bone fragments containing the implants were removed with a trephine and analyzed by Microtomography (µCT, 8.0 µm). The comparison between groups was performed using the unpaired t-test (α=0.05). The results revealed that OD promotes a higher insertion torque (CT: 7.67±2.44 Ncm; OD: 19.78±5.26 Ncm) (p=0.0005), although ISQ was not different (CT: 61.33±4.66; OD: 63.25±4.58) (p=0.48). There was a significant increase in peri-implant bone volume (CT: 23.17±3.39 mm3; OD: 32.01±5.75 mm3) (p=0.008), and trabecular parameters: separation (CT: 0.4357±0.03 mm; OD: 0.3865±0.04 mm) (p=0.0449), number (CT: 1.626±0.18 1/mm; OD: 1.946±0.13 1/mm) (p=0.007), and thickness (CT: 0.1130±0.009 mm; OD: 0.1328±0.015 mm) (p=0.02). Structure model index (SMI) data demonstrate no significant differences between groups (CT: 1.7±0.2; OD: 1.4±0.4) (p=0.12). In conclusion, OD increases the insertion torque values and promotes beneficial changes regarding bone microarchitecture compared with CT, revealing more peri-implant bone volume with consequent higher primary stability. Abstract situations (CT (OD Versah USA. USA . USA) IT, , (IT) ISQ, (ISQ) periimplant peri pigs pig s n=12, n12 n n=12 12 (n=12) n=6 n6 6 (n=6 n=6. procedure 3.5x8.5 35x85 x 3 5x8 5 (3.5x8. mm Brazil. Brazil Brazil) analysis Then µCT, µCT (µCT 80 8 0 8. µm. µm µm) ttest t test α=0.05. α005 α α=0.05 05 (α=0.05) 767244 7 67 2 44 7.67±2.4 Ncm 1978526 19 78 26 19.78±5.2 p=0.0005, p00005 p p=0.0005 0005 (p=0.0005) 61.33±4.66 6133466 61 33 4 66 63.25±4.58 6325458 63 25 58 p=0.48. p048 p=0.48 48 (p=0.48) 2317339 23 17 39 23.17±3.3 mm3 3201575 32 01 75 32.01±5.7 p=0.008, p0008 p=0.008 008 (p=0.008) parameters 04357003 4357 03 0.4357±0.0 03865004 3865 04 0.3865±0.0 p=0.0449, p00449 p=0.0449 0449 (p=0.0449) 1626018 1 626 18 1.626±0.1 1/mm 1mm 1946013 946 13 1.946±0.1 p=0.007, p0007 p=0.007 007 (p=0.007) 011300009 1130 009 0.1130±0.00 013280015 1328 015 0.1328±0.01 p=0.02. p002 p=0.02 02 (p=0.02) SMI (SMI 1.7±0.2 1702 1.4±0.4 1404 p=0.12. p012 p=0.12 (p=0.12) conclusion (IT (ISQ n1 n=1 (n=12 n= (n= 3.5x8. 35x8 5x (3.5x8 α00 α=0.0 (α=0.05 76724 7.67±2. 197852 19.78±5. p0000 p=0.000 000 (p=0.0005 61.33±4.6 613346 63.25±4.5 632545 p04 p=0.4 (p=0.48 231733 23.17±3. 320157 32.01±5. p000 p=0.00 00 (p=0.008 0435700 435 0.4357±0. 0386500 386 0.3865±0. p0044 p=0.044 044 (p=0.0449 162601 62 1.626±0. 194601 94 1.946±0. (p=0.007 01130000 113 0.1130±0.0 01328001 132 0.1328±0.0 p00 p=0.0 (p=0.02 1.7±0. 170 1.4±0. 140 p01 p=0.1 (p=0.12 (n=1 (n 3.5x8 35x (3.5x α0 α=0. (α=0.0 7672 7.67±2 19785 19.78±5 (p=0.000 61.33±4. 61334 63.25±4. 63254 p0 p=0. (p=0.4 23173 23.17±3 32015 32.01±5 (p=0.00 043570 43 0.4357±0 038650 38 0.3865±0 p004 p=0.04 (p=0.044 16260 1.626±0 19460 9 1.946±0 0113000 11 0.1130±0. 0132800 0.1328±0. (p=0.0 1.7±0 1.4±0 14 (p=0.1 3.5x α=0 (α=0. 767 7.67± 1978 19.78± 61.33±4 6133 63.25±4 6325 p=0 (p=0. 2317 23.17± 3201 32.01± 04357 0.4357± 03865 0.3865± (p=0.04 1626 1.626± 1946 1.946± 011300 0.1130±0 013280 0.1328±0 1.7± 1.4± α= (α=0 76 7.67 197 19.78 61.33± 613 63.25± 632 p= (p=0 231 23.17 320 32.01 0435 0.4357 0386 0.3865 162 1.626 194 1.946 01130 0.1130± 01328 0.1328± 1.7 1.4 (α= 7.6 19.7 61.33 63.25 (p= 23.1 32.0 043 0.435 038 0.386 16 1.62 1.94 0113 0.1130 0132 0.1328 1. (α 7. 19. 61.3 63.2 (p 23. 32. 0.43 0.38 1.6 1.9 011 0.113 013 0.132 61. 63. 0.4 0.3 0.11 0.13 0. 0.1

Aim To determine new energy parameters in micro-CT to allow appropriate segmentation of dental cementum from the surrounding structures. Methods For this pilot study, 11 single-rooted premolar teeth of young subjects aged 12 to 21 were selected. The teeth were scanned using high-energy microtomography (SkyScan 1173, Bruker) with varying acquisition energies (60, 70, and 80 kV). Each tooth was scanned three times. The images were reconstructed and analyzed by calculating the volume (mm3) of dental cementum in the cervical, middle, and apical root thirds among the different scanned stacks. The mean cementum volume in the root thirds was obtained, and correlated with the patient’s age, using Pearson’s correlation. Results The mean age of the patients in the sample was 16,73 years. For the 60kV energy, the cementum volumes were 1.01 mm3, 1.00 mm3, and 0.58 mm3, for the cervical, middle, and apical thirds, respectively. For 70kV, it was 1.08 mm3, 1.20 mm3, and 0.71 mm3 for the respective thirds. And for 80kV,0.55 mm3, 0.91 mm3, and 0.67 mm3 for the respective thirds. Conclusion An acquisition energy of 70kV resulted in the best segmentation and reproducibility of the results. Micro-CT can be a useful tool to non-destructively evaluate the dental cementum. microCT micro CT structures study 1 singlerooted single rooted 2 selected highenergy high SkyScan 1173 Bruker 60, 60 (60 70 8 kV. kV . kV) times mm (mm3 cervical middle stacks obtained patient s Pearsons Pearson correlation 1673 16 73 16,7 years 101 01 1.0 100 00 058 0 58 0.5 respectively 108 08 120 20 1.2 071 71 0.7 80kV055 80kV 55 80kV,0.5 091 91 0.9 067 67 0.6 results MicroCT Micro nondestructively non destructively 117 6 (6 7 (mm 167 16, 10 1. 05 5 0. 07 80kV05 80kV,0. 09 9 06 ( 80kV0 80kV,0 80kV,

ABSTRACT Objective: To compare the agreement of images in white light (WL), fluorescence (FL), and digital radiographs (DR), on the diagnosis and treatment decisions for occlusal caries lesions against a micro-CT gold standard. Material and Methods: Ten extracted third molars, with enamel and/or dentin caries (ICDAS 2-4), were included. Occlusal surface images were acquired with an intraoral camera (SoproLife®) in WL and FL modes. DR was obtained using an intraoral X-ray and a semi-direct digital system. A total of 780 images were needed, organized in a template, to be later examined by twenty-six dentists invited to compose the study. The Generalized Estimation Equations model was used to compare the proportions of the correct answers between the three methods and the gold standard. When significant, Bonferroni post-hoc test was used to identify differences (α=5%). Results: Most of the examiners were specialists (76.9%) with 14.5 years of experience. All diagnostic methods were similar and showed low agreement (DR 12.7%, WL 16.5%, and FL 16.5%) compared with gold standard caries diagnostic scores. Regarding treatment decisions, mean agreement for all diagnostic methods was higher (43.2%; p<0.001), and among all methods, WL (48.1%) and FL (51.2%) modes performed better than DR (30.4%, p<0.001). Conclusion: SoproLife® images could help clinicians to propose rational, minimally invasive treatments for occlusal caries lesions. Objective WL, , (WL) FL, (FL) DR, (DR) microCT micro CT Methods molars andor or ICDAS 24, 24 2 4 2-4) included SoproLife (SoproLife® Xray X ray semidirect semi direct system 78 needed template twentysix twenty six study significant posthoc post hoc α=5%. α5 α α=5% . 5 (α=5%) Results 76.9% 769 76 9 (76.9% 145 14 14. experience 127 12 7 12.7% 165 16 16.5% scores 43.2% 432 43 (43.2% p<0.001, p0001 p p<0.001 0 001 p<0.001) 48.1% 481 48 1 (48.1% 51.2% 512 51 (51.2% 30.4%, 304 30 (30.4% p<0.001. Conclusion rational (WL (FL 2-4 (SoproLife α=5 (α=5% 76.9 (76.9 12.7 16.5 43.2 (43.2 p000 p<0.00 00 48.1 (48.1 51.2 (51.2 30.4% 3 (30.4 2- α= (α=5 76. (76. 12. 16. 43. (43. p00 p<0.0 48. (48. 51. (51. 30.4 (30. (α= (76 (43 p0 p<0. (48 (51 30. (30 (α (7 (4 p<0 (5 (3 ( p<

Abstract Objective: To evaluate the efficacy of silver diamine fluoride (SDF) in arresting dentin caries lesions when applied under different concentrations and times. Material and Methods: Forty-two bovine blocks were selected and fixed in 24-well plates. Each well received a mixed bacterial inoculum added to the culture medium with 5% sucrose. The plates were incubated in microaerophilia (7 days) for caries formation, confirmed by micro-CT (M1). SDF was applied over the carious lesions for different times and concentrations (n=6): SDF 30% - immediate removal, 1 minute and 3 minutes; SDF 38%, - immediate removal, 1 minute and 3 minutes. The group without treatment was the control. Then, the samples were again scanned by micro-CT (M2) and submitted to a second cariogenic challenge for 21 days. Then, a final scan was performed (M3). Results: Mean pH at the culture medium and lesion depth were compared using Kruskal-Wallis and Wilcoxon tests. 38% SDF showed the lowest metabolic activity of the biofilm. All 38% groups and 30% 1 and 3 minutes did not show an increase in mean lesion depth comparing M3 with M1. However, only 30% 3 minutes and 38% 1 and 3 minutes showed a significant reduction of lesion depth. Conclusion: The minimum application time of 30% SDF to arrest dentin caries lesion was 1 minute, while 38% SDF arrested with application and immediate removal.

RESUMO Este estudo teve como objetivo avaliar o efeito in vitro de uma única aplicação de soluções experimentais de nanocompósitos na prevenção de cárie dentária em braquetes ortodônticos. Os espécimes foram expostos a nanocompósitos de sílica mesoporosa (MS) contendo fluoreto por associação com tetrafluoreto de titânio (TiF4) ou fluoreto de sódio (NaF). Os nanocompósitos também podem conter cálcio e os grupos foram descritos como MSCaTiF4, MSTiF4, MSCaNaF, MSNaF e controles (TiF4 e NaF). Os espécimes foram submetidos à formação de um biofilme multiespécie para gerar um desafio cariogênico. Após 24h, o pH e a concentração de flúor solúvel total do meio de cultura foram avaliados. A perda mineral foi avaliada pela porcentagem de perda mineral superficial (% SML), variação do volume mineral (ΔZ) do esmalte interno e microscopia de luz polarizada (PL). A rugosidade superficial linear (Ra) e volumétrica (Sa) e a microscopia eletrônica de varredura (MEV) foram utilizadas para avaliar a topografia do esmalte. As análises estatísticas foram realizadas considerando p <0,05. MSNaF apresentou o maior valor de pH do meio de cultura após o desafio cariogênico, semelhante ao MSTiF4. Todas as soluções de nanocompósitos liberaram menos flúor do que seus controles NaF e TiF4 (p <0,05). Todas as soluções de nanocompósitos apresentaram% SML menor em comparação com seus respectivos grupos de controle (p <0,05). Ra, Sa e ΔZ menores foram observados para os grupos experimentais em comparação ao TiF4 (p <0,05). Os resultados foram confirmados por análises PL e SEM. As soluções experimentais de nanocompósitos contribuíram para a menor desmineralização do esmalte ao redor dos braquetes ortodônticos.

Abstract This study aimed to evaluate the in vitro effect of a single application of experimental nanocomposite solutions on the prevention of dental caries around orthodontic brackets. The specimens were exposed to mesoporous silica (MS) nanocomposites containing fluoride by association with titanium tetrafluoride (TiF4) or sodium fluoride (NaF). Nanocomposites also could contain calcium and groups were described as MSCaTiF4, MSTiF4, MSCaNaF, MSNaF, and controls (TiF4, and NaF). Specimens were subjected to the formation of a multispecies biofilm to generate a cariogenic challenge. After 24h, both pH and total soluble fluoride concentration of the culture medium were assessed. Mineral loss was evaluated by percentage of surface mineral loss (%SML), mineral volume variation (ΔZ) of inner enamel and polarized light microscopy (PL). Linear (Ra) and volumetric (Sa) surface roughness and scanning electronic microscopy (SEM) were used to assess enamel topography. Statistical analyses were conducted considering p<0.05. MSNaF had the highest value of culture medium pH after cariogenic challenge, similarly to MSTiF4. All nanocomposite solutions released less fluoride than their controls NaF and TiF4 (p<0.05). All nanocomposite solutions presented lower %SML compared to their respective control groups (p<0.05). Lower Ra, Sa and ΔZ were observed for experimental groups compared to TiF4 (p<0.05). The results were confirmed by PL and SEM analysis. The experimental nanocomposite solutions contributed for lower enamel demineralization around orthodontic brackets.

Abstract This study aimed to evaluate the endodontic instrumentation outcomes with asymmetrical files compared to reciprocating and hand files (HFs) in 3D-printed prototypes of upper primary incisors using micro-computed tomography (micro-CT). For this purpose, 50 prototypes were randomly divided (n = 10) according to the instrumentation technique as follows: HFs, a reciprocating file (WaveOne® Gold [WOG]), and three asymmetrical movement files: XP-Endo® Shaper (XPS), XP-Endo® Finisher (XPF), and XP Clean (XPC). The specimens were scanned and, after registration of the baseline and instrumented volumes, changes in the root canal volume (RCV), debris accumulation, removed root material volume (RRMV), non-instrumented areas, and the presence of cracks/perforations were quantified. Data were analyzed by analysis of variance and Student’s t-test, while the effect size was calculated for statistically significant outcomes. All groups showed an increase in RCV after instrumentation (p < 0.05), but this was higher with HFs (p < 0.05). Accumulated debris was higher for WOG and XPS (p < 0.05), but WOG exhibited more in the medium and apical third areas. HFs showed the highest RRMV (p < 0.05), especially at the apical third. The non-instrumented areas were lower for HFs and XPC than for the other systems (p < 0.05). Cracks were present in a few WOG (n = 2) and HF specimens (n = 3) and in this group, one of the cracked specimens and two others showed perforations. The asymmetric systems resulted in conservative dentin removal and fewer cracks/perforations as compared to HFs and a reciprocation file in prototyped primary upper incisors. XPC showed the best compromise between RRMV and non-instrumented areas with a low accumulation of debris.

Resumo Objetivo: Avaliar e reconstruir imagens tridimensionais da vascularização ao longo da trompa de Falópio (TF) e sua relação com o ovário e fímbria do ovário, além de quantificar os vasos sanguíneos ao longo da TF de acordo com seus segmentos anatômicos usando microtomografia confocal (micro-TC). Materiais e Métodos: Nove espécimes (seis com TFs e três com TFs e ovários) foram fixados em solução de formol a 10% por mais de 24 h à temperatura ambiente. A coloração com iodo foi realizada usando solução de Lugol a 10% durante 24 h. Todos os espécimes foram avaliados usando micro-TC. Uma análise morfométrica foi realizada nas imagens reconstruídas para quantificar a distribuição vascular ao longo da TF. Resultados: A densidade dos vasos sanguíneos nas fímbrias foi significativamente aumentada em comparação ao segmento ístmico da TF (p < 0,05). A fímbria ovariana foi claramente identificada, demonstrando importante relação entre esses vasos e as fímbrias da TF. Conclusão: Acreditamos que as fímbrias apresentam vascularização aumentada e desproporcional em comparação com os demais segmentos da TF e que a fímbria ovariana desempenha importante papel nessa diferença.

Abstract Objective: To evaluate and reconstruct three-dimensional images of vascularization along the fallopian tube (FT), as well as to determine its relationship with the ovary and ovarian fimbria, and to quantify the blood vessels along the FT according to its anatomical segments, using confocal microtomography (micro-CT). Materials and Methods: Nine specimens (six FTs and three FTs with ovaries) were fixed in a solution of 10% formalin for > 24 h at room temperature. Iodine staining was performed by soaking the specimens in 10% Lugol’s solution for 24 h. All specimens were evaluated using micro-CT. A morphometric analysis was performed on the reconstructed images to quantify the vascular distribution along the FT. Results: In the FTs evaluated, the density of blood vessels was significantly greater in the fimbrial segments than in the isthmic segments (p < 0.05). The ovarian fimbria was clearly identified, demonstrating the important relationship between these vessels and the FT fimbriae. Conclusion: We believe that the vascularization in the fimbriae is greater than and disproportional that in the other segments of FT, and that the ovarian fimbria plays an important role in the development of that difference.

Abstract Objective: To compare the immediate microleakage of carious fissures sealed with a caries infiltrant covered by a flowable composite or solely with a flowable composite. Material and Methods: Extracted carious molars (n=20) were selected and paired among the experimental groups according to caries progression scores. Experimental groups (n=10) were divided according to the following sealing techniques: 1) caries infiltrant (Icon) + flowable composite (Z350 flow); 2) flowable composite (Z350 flow). Specimens were immersed in 3% methylene blue and evaluated in a stereomicroscope. Microleakage scores were attributed independently by two calibrated evaluators and the mode value was considered as the mean for the specimen. Binomial tests were used to test differences between two independent sample proportions at 5% significance level. Results: In the flowable composite group, a higher prevalence of dye penetration along the full depth of the fissure was observed, compared with caries infiltrant + flowable composite (p<0.05). For specimens showing dye penetration up to half of the fissure, in caries infiltrant + flowable composite group, all specimens showed dye penetration into the sealant, but not over the infiltrant. Conclusion: Using caries infiltrant as sealing material under a flowable composite cover is effective to improve the immediate sealing ability in carious fissures compared to sealing with flowable composite.

Resumo Para avaliar o volume de fissuras dentinárias levando em consideração a idade da dentina e o tipo de sistema de limas utilizadas para procedimentos endodônticos, 40 dentes unirradiculares, incisivos inferiores, apresentando similar volume radicular, recentemente extraídos foram divididos em dois grupos de acordo com a idade do paciente: Grupo Jovem (18 a 30 anos) e Grupo Idoso (60 anos ou mais). Cada espécime foi scaneada por microtomografia computadorizada (micro-CT) em três estágios: (i) antes de qualquer tratamento, (ii) após tratamento endodôntico com limas Reciproc (REC) e (iii) após subsequente retratamento endodôntico. Cada grupo foi subdividido em dois subgrupos, de acordo com a técnica de retratamento utilizada: retratamento com REC ou com lima ProTaper Universal Retreatment (PUR). As imagens foram analisadas quanto às diferenças no volume das fissuras dentinárias nos terços médio e apical dos dentes de acordo com a idade da dentina. Em ambos os estágios (antes e depois da instrumentação), as imagens de micro-CT da dentina radicular idosa apresentaram maior volume de trincas do que as jovens, sem significância estatística (p>0.01). O uso das limas REC mostram não ter diferença estatística significante na geração de fissuras, em qualquer tipo de dentina, quando comparadas às limas PUR (p>0.01). Quando retratada com PUR, a dentina radicular idosa apresentou um volume de trincas significativamente maior (p<0.01) quando comparado com a dentina radicular idosa inicialmente.

Abstract In order to evaluate the volume of dentinal cracks taking into account the age of the dentin and the type of file system used for endodontic procedures, forty freshly extracted single-rooted lower incisive teeth presenting similar root volume, were divided into two groups according to the age of the patient: Group Young (18 - 30 years old) and Group Old (60 years old or more). Each specimen was scanned by microcomputed tomography (micro-CT) in three stages: (i) before any treatment, (ii) after endodontic treatment with Reciproc files (REC), and (iii) after subsequent endodontic retreatment. Each group was subdivided into two subgroups, according to the retreatment technique used: retreatment with REC or with ProTaper Universal Retreatment (PUR) files. For each subgroup, the images were analyzed for differences in the volume of dentinal cracks in the middle and apical thirds of the teeth , according to the dentin age. In both stages (before and after instrumentation), the micro-CT images of the old root dentin presented with higher volume of cracks than those of the young root dentin, statistical significance notwithstanding (p>0.01). The use of REC files appeared to have no statistically significant differences in the generation of cracks in any type of root dentin when compared with PUR files (p>0.01). When retreated with PUR, the old root dentin presented with a significantly higher volume of cracks (p<0.01) when compared with the old root dentin initially.

Abstract The aim of this study was to check the in vitro accuracy of ICDAS criteria on digital images compared to visual examination for the diagnosis of occlusal caries against a micro-CT gold standard. ICDAS was scored in 40 extracted permanent molars by means of visual inspection and stereomicroscopic images. Visual examinations were performed in duplicate and at a one-week interval by three different calibrated examiners. The analysis of digital images by ICDAS criteria was also performed in duplicate, 1 month after visual examinations. The detection methods were compared by means of sensitivity, specificity, area under the curve, predictive positive and negative values, and accuracy for two different thresholds (1- sound vs. carious teeth; 2- tooth requiring operative vs. non-operative treatment). Sensitivity and accuracy values for threshold 1 in the visual ICDAS and image-based ICDAS methods were high for sensitivity (0.93 and 0.97) and for accuracy (0.83 and 0.85), but low for specificity (0.55 for both methods). Specificity values for threshold 2 were 0.77 and 0.82, while sensitivity was 0.33 and 0.28 for each method. Spearman’s rank correlation coefficient was 0.53 and 0.43 (p<0.05) for visual and image-based ICDAS compared to the gold standard scores. Both visual and image-based ICDAS scores were similar to each other in terms of diagnostic accuracy when compared to the micro-CT gold standard. Low specificity for the presence of caries and sensitivity for the detection of caries requiring operative treatment were found.

Resumo O objetivo deste estudo foi avaliar a relação de causa-efeito entre o preparo do canal radicular com o sistema ProTaper Universal (PTU) e a formação de defeitos dentinários usando a análise por micro-tomografia computadorizada (micro-CT). Quarenta raízes mesiais de molares inferiores com a configuração tipo II de Vertucci foram escaneadas com resolução isotrópica de 14.16 μm. A amostra foi distribuída em um grupo experimental (n = 30) e um grupo controle (n = 10), e os canais mesiais foram preparados com o sistema PTU até a lima F2. As amostras do grupo experimental foram escaneadas e as imagens de secção transversal das raízes mesiais, antes e após o preparo, foram analisadas para identificar a presença de defeitos dentinários. No grupo controle, os dentes foram seccionados perpendicularmente em relação ao longo eixo da raiz em fatias de 1 mm de espessura (n = 80) e examinados ao microscópio óptico. Uma vez detectado um defeito dentinário, a fatia foi escaneada através da micro-CT. No grupo experimental, defeitos dentinários foram observados em 4.828 secções transversais (24,04%). Em todas as imagens de secção transversal, os defeitos dentinários após os procedimentos experimentais já estavam presentes na secção pré-operatória correspondente. No grupo controle, 13 das 80 fatias (16,25%) apresentaram pelo menos um defeito dentinário visualizado através do microscópio, o qual foi identificado em um escaneamento posterior. A micro-CT mostrou confiabilidade com a microscopia óptica para detecção e visualização dos defeitos dentinários, permitindo acompanhar o tecido dentinário antes e depois do preparo do canal. O preparo do canal radicular com o sistema PTU não induziu a formação de novos defeitos dentinários.

Abstract This study aimed to evaluate the cause-effect relationship between canal preparation with ProTaper Universal (PTU) system and dentinal defects formation using micro-computed tomography (micro-CT) analysis. Forty mesial canals of mandibular molars with a type II Vertucci's canal configuration were scanned at an isotropic resolution of 14.16 µm. The sample was assigned to an experimental (n = 30) and a control (n = 10) groups, and the mesial canals were prepared with PTU system up to F2 instrument. The specimens from the experimental group were scanned and the cross-section images of the mesial roots, before and after preparation, were screened to identify the presence of dentinal defects. In the control group, the specimens were sectioned perpendicularly to the long axis of the root into 1-mm-thick slices (n = 80) and examined under optical microscope. Once a dentinal defect was detected, the slice was scanned through micro-CT. In the experimental group, dentinal micro-cracks were observed in 4,828 slices (24.04%). In all cross-section images, dentinal defects identified in the postoperative images were already present in the corresponding preoperative image. In the control group, 13 out of 80 slices (16.25%) had at least one dentinal defect visualized under stereomicroscopy, which was identified after a further micro-CT scanning. Micro-CT showed reliability as similar as optical microscopy in detecting dentinal defects, adding the possibility of tracking the dentinal tissue, before and after canal preparation, and providing a clear visualization of micro-cracks. Root canal preparation with PTU system did not induce the formation of new dentinal defects.

Resumo O objetivo deste estudo foi comparar a porcentagem de área não-instrumentada de canais radiculares preparados com diferentes ampliações utilizando sistemas reciprocantes de lima única (Reciproc e WaveOne) e um sistema rotatório convencional de múltiplas limas (BioRaCe) usando a análise da micro tomografia computadorizada. Trinta raízes mesiais de molares inferiores com curvatura moderada (10º a 20º) apresentando a configuração classe II de Vertucci e semelhança de volume do canal foram selecionadas e escaneadas em uma resolução isotrópica de 14,16 µm. A amostra foi dividida em 3 grupos (n=10) de acordo com o sistema utilizado para a preparação do canal radicular: grupo Reciproc, grupo WaveOne e grupo BioRaCe. Segundo e terceiro escaneamentos foram realizados após os canais serem preparados com instrumentos tamanhos 25 e 40, respectivamente. As imagens registradas de voxels da área de superfície dos canais, antes e após o preparo, foram examinadas desde o nível da furca até o ápice para quantificar a superfície não instrumentada. Os dados foram comparados estatisticamente através de GLM para medidas repetidas com um nível de significância de 5%. Os sistemas de instrumentação não influenciaram o percentual de superfícies não tocadas dos canais radiculares (p=0,690), enquanto que uma redução significativa no percentual de voxels estáticos foi observada após o alargamento do canal radicular (p=0,010) em todos os grupos (p=0,507). Nenhum dos sistemas foi capaz de preparar toda a área de superfície do canal mesial dos molares inferiores. O aumento do tamanho final apical resultou num efeito positivo significativo sobre a capacidade de modelar dos sistemas testados.

The aim of this study was to compare the percentage of non-instrumented area of root canals prepared with different enlargements using single-file reciprocating systems (Reciproc and WaveOne) and a conventional multi-file rotary (BioRaCe) system by micro-computed tomographic analysis. Thirty mesial roots of mandibular molars with moderate curvature (10° to 20°) presenting a type II Vertucci canal configuration and similar internal volume were chosen and scanned at an isotropic resolution of 14.16 µm. The sample was assigned to 3 groups (n=10) according to the system used for root canal preparation: Reciproc, WaveOne, and BioRaCe groups. Second and third scans were taken after the canals were prepared with instruments sizes 25 and 40, respectively. The recorded images of the surface area voxels of the canals, before and after preparation were examined from the furcation level to the apex to quantify the non-instrumented surface. Statistical data were compared using GLM for repeated-measures with a significance level set at 5%. Instrumentation systems did not influence the percentage of untouched root canal surfaces (p=0.690) whilst a significant reduction in the percentage of static voxels was observed after the enlargement of the root canal (p=0.010) in all groups (p=0.507). None of the systems was able to prepare the entire surface area of the mesial root canal of mandibular molars. The increased final apical size resulted in a significant positive effect on the shaping ability of the tested systems.

Duplex stainless steel is an example of composite material with approximately equal amounts of austenite and ferrite phases. Difference of physical and mechanical properties of component is additional factor that contributes appearance of residual stresses after welding of duplex steel plates. Measurements of stress distributions in weld region were made by X-ray diffraction method both in ferrite and austenite phases. Duplex Steel plates were joined by GTAW (Gas Tungsten Arc Welding) technology. There were studied longitudinal and transverse stress components in welded butt joint, in heat affected zone (HAZ) and in points of base metal 10 mm from the weld. Residual stresses measured in duplex steel plates jointed by welding are caused by temperature gradients between weld zone and base metal and by difference of thermal expansion coefficients of ferrite and austenite phases. Proposed analytical model allows evaluating of residual stress distribution over the cross section in the weld region.

Este artigo apresenta os resultados da análise de fragmentos de peroleiras e cachimbos cerâmicos, oriundos de escavações arqueológicas realizadas na região compreendida entre os rios Macacu e Caceribu, no estado do Rio de Janeiro, utilizando as técnicas de Fluorescência de Raios X (XRF), Microscopia Eletrônica de Varredura, com Espectroscopia por Dispersão em Energia (SEM-EDS) e estatística multivariada. Algumas peroleiras provenientes do naufrágio do galeão Santíssimo Sacramento, que ocorreu no litoral da Bahia em 1688, foram igualmente analisadas, e os resultados comparados com aqueles obtidos para os fragmentos encontrados no Rio de Janeiro. Nesse contexto, é proposta uma metodologia de análise para artefatos cerâmicos que possa auxiliar não somente a sua caracterização, como também fornecer suporte para a construção de interpretações concernentes à produção e à utilização desses objetos.

This article presents the results of the analysis of olive jars and ceramic pipes fragments, from archaeological excavations performed in the region located between the rivers Macacu and Caceribu, in the state of Rio de Janeiro, using the techniques of X-ray Fluorescence (XRF), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) and multivariate statistics. Some olive jars from the shipwreck of the Galleon Santíssimo Sacramento, which occurred in the coastal of Bahia in 1688, were also analyzed and the results compared with those obtained for the fragments found in Rio de Janeiro. In this context, is proposed a methodology of analysis for ceramic artifacts which can assist not only in its characterization, as also provide support for constructing interpretations concerning the production and use of these objects.