1.Optimizing cone-beam computed tomography exposure for an effective radiation dose and image quality balance
Ananda Amaral SANTOS ; Brunno Santos de Freitas SILVA ; Fernanda Ferreira Nunes CORREIA ; Eleazar MEZAIKO ; Camila Ferro de Souza RORIZ ; Maria Alves Garcia SILVA ; Deborah Queiroz FREITAS ; Fernanda Paula YAMAMOTO-SILVA
Imaging Science in Dentistry 2024;54(2):159-169
Purpose:
The aim of this study was to evaluate the influence of different cone-beam computed tomography (CBCT) acquisition protocols on reducing the effective radiation dose while maintaining image quality.
Materials and Methods:
The effective dose emitted by a CBCT device was calculated using thermoluminescent dosimeters placed in a Rando Alderson phantom. Image quality was assessed by 3 experienced evaluators. The relation-ship between image quality and confidence was evaluated using the Fisher exact test, and the agreement among raters was assessed using the kappa test. Multiple linear regression analysis was performed to investigate whether the technical parameters could predict the effective dose. P-values<0.05 were considered to indicate statistical significance.
Results:
The optimized protocol (3 mA, 99 kVp, and 450 projection images) demonstrated good image quality and a lower effective dose for radiation-sensitive organs. Image quality and confidence had consistent values for all structures (P<0.05). Multiple linear regression analysis resulted in a statistically significant model. The milliamperage (b = 0.504; t = 3.406; P = 0.027), kilovoltage peak (b = 0.589; t = 3.979; P = 0.016) and number of projection images (b = 0.557; t = 3.762; P = 0.020) were predictors of the effective dose.
Conclusion
Optimized CBCT acquisition protocols can significantly reduce the effective radiation dose while maintaining acceptable image quality by adjusting the milliamperage and projection images.
2.Use of the n-butyl cyanoacrylate adhesive and the polyglactine thread suture for corneal rhaphy in rabbit (Oryctolagus cunicullus).
Francisco Claudio Dantas MOTA ; Duvaldo EURIDES ; Patricia Maria Coletto FREITAS ; Marcelo Emilio BELETTI ; Michelle Rodriques GOULART ; Livia Maria Ferreira CUNHA ; Luiz Antonio Franco DA SILVA ; Maria Clorinda Soares FIORAVANTI
Journal of Veterinary Science 2004;5(3):267-270
The aim of this study was to evaluate the cicatricial repair of perforating cornea in rabbits, by using the Nbutyl cyanoacrylate adhesive compared to the 910-polyglactine thread suture through macroscopic and histological assays. Corneas from 18 adult rabbits were perforated and subsequently occluded with N-butyl cyanoacrylate synthetic adhesive (right cornea) or by separated single points using the 910-polyglactine thread (left cornea). The rabbits were divided into groups containing three animals per group. Examination after 7, 15, and 30 days post-operative showed that both the synthetic adhesive and the suture were efficient in the occlusion of the surgical wounds, thus stabilizing the intra-ocular content. The N-butyl cyanoacrylate adhesive was shown to be superior to the 910-polyglactine suture thread with regards to the evolution and the organization of the healing process.
Animals
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Cornea/*injuries/*surgery
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Enbucrilate/*therapeutic use
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Female
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Male
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Polyglactin 910/therapeutic use
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Rabbits/*surgery
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*Sutures
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Tissue Adhesives/*therapeutic use
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*Wound Healing
3.Physicochemical characterization, the Hirshfeld surface, and biological evaluation of two meloxicam compounding pharmacy samples
Romani F.A. LUCIANA ; Yoshida I. MARIA ; Gomes C.L. ELIONAI ; Machado R. RENES ; Rodrigues F. FELIPE ; Coelho M. MÁRCIO ; Oliveira A. MARCELO ; Freitas-Marques B. MARIA ; Rosane A.S. San Gil ; Mussel N. WAGNER
Journal of Pharmaceutical Analysis 2018;8(2):103-108
Meloxicam (MLX) is an anti-inflammatory drug susceptible to variations and crystalline transitions. In compounding pharmacies, the complete crystallographic evaluation of the raw material is not a routine procedure. We performed a complete crystallographic characterization of aleatory raw MLX samples from compounding pharmacies. X-ray diffraction indicated the presence of two crystalline forms in one sample. DSC experiments suggested that crystallization, or a crystal transition, occurred differently be-tween samples. The FTIR and 1H NMR spectra showed characteristic assignments. 13C solid-state NMR spectroscopy indicated the presence of more than one phase in a sample from pharmacy B. The Hirshfeld surface analysis, with electrostatic potential projection, allowed complete assignment of the UV spectra in ethanol solution. The polymorph I of meloxicam was more active than polymorph Ⅲ in an experi-mental model of acute inflammation in mice. Our results highlighted the need for complete crystal-lographic characterization and the separation of freely used raw materials in compounding pharmacies, as a routine procedure, to ensure the desired dose/effect.
4.Positioning errors of dental implants and their associations with adjacent structures and anatomical variations: A CBCT-based study
Beatriz Ribeiro RIBAS ; Eduarda Helena LEANDRO NASCIMENTO ; Deborah Queiroz FREITAS ; Andréa dos ANJOS PONTUAL ; Maria Luiza dos ANJOS PONTUAL ; Danyel Elias CRUZ PEREZ ; Flávia Maria Moraes RAMOS-PEREZ
Imaging Science in Dentistry 2020;50(4):281-290
Purpose:
The objective of the present study was to evaluate the prevalence of dental implants positioning errors and their associations with adjacent structures and anatomical variations by means of cone-beam computed tomography (CBCT).
Materials and Methods:
CBCT images of 207 patients (584 dental implants) were evaluated by 2 oral radiologists. The distance between the implant and the adjacent teeth/implants was measured and classified as adequate (≥1.5 mm and ≥3 mm, respectively) or inadequate. The presence of thread exposure, cortical perforation, implant dehiscence, implant penetration into adjacent structures, and anatomical variations was also recorded. The incisor canal diameter and the depth of the concavity of the submandibular fossa were measured in order to evaluate their correlations with the frequency of implant penetration in these structures. Descriptive analyses, the Fisher exact test, and Spearman correlation analysis were performed (α= 0.05).
Results:
The overall prevalence of positioning errors was 82.9%. The most common error was the inadequate distance between the implant and the adjacent teeth/implants. The presence of anatomical variations did not significantly influence the overall prevalence of errors (P>0.05). There was a positive correlation between the diameter of the incisor canal and the frequency of implant penetration in this structure (r= 0.232, P<0.05).
Conclusion
There was a high prevalence of dental implant positioning errors, and positioning errors were not associated with the presence of anatomical variations. Professionals should be aware of the space available for implant placement during the preoperative planning stage.
5.Chemical composition, antiparasitic and cytotoxic activities of aqueous extracts of Ziziphus joazeiro Mart
Andrade Cosmo JACQUELINE ; Ana Raquel Pereira da Silva ; Ant?nia Thassya Lucas dos Santos ; Freitas Audilene MARIA ; Yedda Maria Lobo Soares de Matos ; Maria Flaviana Bezerra Morais Braga ; Bezerra Fonseca CAMILA ; Maria Isabeli Pereira Gon?alo ; Maria Celeste Vega Gomez ; Míriam Rolóm Cathia Coronel ; Paulo Riceli Vasconcelos Ribeiro ; Edy Sousa de Brito ; Henrique Douglas Melo Coutinho
Asian Pacific Journal of Tropical Biomedicine 2019;9(5):222-226
Objective: To compare the in vitro antiparasitic activity of aqueous extracts from Ziziphus joazeiro leaves and stem bark against Trypanosoma cruzi, Leishmania braziliensis, and Leishmania infantum, as well as to evaluate its cytotoxicity in mammalian cells, in addition to identifying the chemical composition of the extracts. Methods: Ziziphus joazeiro leaf and stem bark aqueous extracts were prepared by cold extraction maceration and subjected to ultra-efficient liquid chromatography coupled to a quadrupole/time of flight system. The susceptibility assays used Trypanosoma cruzi CL-B5 strains and promastigote forms of Leishmania braziliensis and Leishmania infantum for antiparasitic activity of the extracts. Moreover, mammalian fibroblasts NCTC clone 929 were used for cytotoxicity analysis. Results: Terpenoid compounds, flavonoids and phenolic acid were identified in extracts. The stem bark aqueous extracts presented more significant results in terms of antiparasitic activity compared with the leaf aqueous extracts, especially against Leishmania braziliensis and Leishmania infantum promastigote forms with an IC50 < 500 μg/mL. The cytotoxicity evaluation showed moderate toxicity of the stem bark aqueous extracts, which is relevant information for the rational use of this plant part since it is widely used by the population. Conclusions: These preliminary results may contribute to the formulation of new therapeutic agents against this group of neglected diseases, so further investigations are required to delineate the mechanisms of action mainly of the aqueous extract of stem bark of Ziziphus joazeiro.
6.Comparing a tablet computer and paper forms for assessing patient-reported outcomes in edentulous patients.
Thais Angelina CAETANO ; Adriana Barbosa RIBEIRO ; Maria Paula DELLA VECCHIA ; Tatiana Ramirez CUNHA ; Carolina de Andrade Lima CHAVES ; Raphael Freitas DE SOUZA
The Journal of Advanced Prosthodontics 2016;8(6):457-464
PURPOSE: The aim of this study was to determine whether two methods of documentation, print and electronic forms, for the assessment of patient-reported outcomes (PRO) in complete denture wearers provide comparable results. The study also quantified the time needed for filling the forms by each method. MATERIALS AND METHODS: Thirty participants enrolled in a university clinic answered two forms (a questionnaire for denture satisfaction and OHIP-EDENT). They provided answers with two application methods in a random order, with a one-month interval between them: (1) electronic forms on a tablet computer; and (2) print forms. The methods were compared in terms of mean results, correlation/agreement, internal consistency, and spent time. RESULTS: Mean results for both methods were similar for each denture satisfaction item (100-mm VAS) and OHIP-EDENT summary score. Both questionnaires presented good internal consistency regardless of the application method (Cronbach's α=0.86 or higher). Correlation and agreement between the methods regarding specific items was at least moderate for the majority of cases. Mean time for the electronic and print forms were 9.2 and 8.5 minutes, respectively (paired t test, P=.06, non-significant). CONCLUSION: The electronic method is comparable to print forms for the assessment of important PRO of prosthetic treatment for edentulism, considering the results and time needed. Findings suggest the viability of replacing print forms with a tablet for applying the tested inventories in clinical trials.
Computers, Handheld*
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Denture, Complete
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Dentures
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Equipment and Supplies
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Humans
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Methods
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Patient Satisfaction
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Quality of Life
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Treatment Outcome
7.Influence of voxel size on cone-beam computed tomography-based detection of vertical root fractures in the presence of intracanal metallic posts
Fernanda Paula YAMAMOTO-SILVA ; Claudeir Felipe DE OLIVEIRA SIQUEIRA ; Maria Alves Garcia Santos SILVA ; Rodrigo Borges FONSECA ; Ananda Amaral SANTOS ; Carlos ESTRELA ; Brunno Santos DE FREITAS SILVA
Imaging Science in Dentistry 2018;48(3):177-184
PURPOSE: This study was performed to evaluate the influence of voxel size and the accuracy of 2 cone-beam computed tomography (CBCT) systems in the detection of vertical root fracture (VRF) in the presence of intracanal metallic posts. MATERIALS AND METHODS: Thirty uniradicular extracted human teeth were selected and randomly divided into 2 groups (VRF group, n=15; and control group, n=15). The VRFs were induced by an Instron machine, and metallic posts were placed in both groups. The scans were acquired by CBCT with 4 different voxel sizes: 0.1 mm and 0.16 mm (for the Eagle 3D V-Beam system) and 0.125 mm and 0.2 mm (for the i-CAT system) (protocols 1, 2, 3, and 4, respectively). Interobserver and intraobserver agreement was assessed using the Cohen kappa test. Sensitivity and specificity were evaluated and receiver operating characteristic analysis was performed. RESULTS: The intraobserver coefficients indicated good (0.71) to very good (0.83) agreement, and the interobserver coefficients indicated moderate (0.57) to very good (0.80) agreement. In respect to the relationship between sensitivity and specificity, a statistically significant difference was found between protocols 1 (positive predictive value: 0.710, negative predictive value: 0.724) and 3 (positive predictive value: 0.727, negative predictive value: 0.632) (P < .05). The least interference due to artifact formation was observed using protocol 2. CONCLUSION: Protocols with a smaller voxel size and field of view seemed to favor the detection of VRF in teeth with intracanal metallic posts.
Artifacts
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Cone-Beam Computed Tomography
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Eagles
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Humans
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ROC Curve
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Sensitivity and Specificity
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Tooth
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Tooth Fractures
8.Questions about “No evidence on the effectiveness of oral splints for the management of temporomandibular joint dysfunction pain in both short and long-term follow-up systematic reviews and meta-analysis studies”
Matheus Souza Campos COSTA ; Sandy Maria da Silva COSTA ; Nicole Rosa de FREITAS ; Luísa Belluco GUERRINI ; Caio Sousa FERRAZ ; Ana Lúcia Pompéia Fraga de ALMEIDA
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2020;46(5):367-368
9.Effect of acidic beverages on surface roughness and color stability of artificial teeth and acrylic resin
Sandro Basso BITENCOURT ; Isabela Araguê CATANOZE ; Emily Vivianne Freitas da SILVA ; Paulo Henrique dos SANTOS ; Daniela Micheline dos SANTOS ; Karina Helga Leal TURCIO ; Aimée Maria GUIOTTI
The Journal of Advanced Prosthodontics 2020;12(2):55-60
PURPOSE:
. The aim was to evaluate the effect of four acidic beverages on the roughness (Ra) and color change (ΔEab) of two brands of artificial teeth and a heat-polymerized acrylic resin (HPAR) for use in a prosthetic base.
MATERIALS AND METHODS:
. All materials were divided into 5 groups, according to the used acidic beverage (artificial saliva - control, red wine, orange juice, coke-based, and lemon juice-based soft drink). The immersion process was divided into two stages: T1 - immersion in the acidic solutions for 10 minutes for 14 days; T2 - after T1, the samples were immersed in grape juice for 14 days. The Ra of the samples was evaluated in a rugosimeter and the ΔEab in a spectrophotometer, before and after the immersions. The analysis of variance of one (ΔEab) and two factors (Ra) and Tukey were performed (α=.05).
RESULTS:
. There was a statistical difference for roughness after immersion (T1) for Trilux and Tritone teeth, regardless of the acid solution. For Trilux teeth, all acid solutions increased Ra (P<.05). For Tritone teeth, only the coke-based soft drink did not statistically change Ra. Grape juice (T2) altered Ra only of artificial teeth (P<.05). The color was changed for all materials, after T1 and T2.
CONCLUSION
. In general, the acidic solutions changed the Ra and ΔEab of HPAR and artificial teeth after T1. The grape juice altered the roughness only of the artificial teeth, promoting a clinically acceptable color change in the materials.
10.Miniscrew insertion sites of infrazygomatic crest and mandibular buccal shelf in different vertical craniofacial patterns: A cone-beam computed tomography study
Murilo MATIAS ; Carlos FLORES-MIR ; Márcio Rodrigues de ALMEIDA ; Bruno da SILVA VIEIRA ; Karina Maria Salvatore de FREITAS ; Daniela Calabrese NUNES ; Marcos Cezar FERREIRA ; Weber URSI
The Korean Journal of Orthodontics 2021;51(6):387-396
Objective:
To identify optimal areas for the insertion of extra-alveolar miniscrews into the infrazygomatic crest (IZC) and mandibular buccal shelf (MBS), using cone beam computed tomography (CBCT) imaging in patients with different craniofacial patterns.
Methods:
CBCT reconstructions of untreated individuals were used to evaluate the IZC and MBS areas. The participants were divided into three groups, based on the craniofacial pattern, namely, brachyfacial (n = 15; mean age, 23.3 years), mesofacial (n = 15; mean age, 19.24 years), and dolichofacial (n = 15; mean age, 17.79 years). In the IZC, the evaluated areas were at 11, 13, and 15 mm above the buccal cusp tips of the right and left first molars. In the MBS, the evaluated areas were at the projections of the first molars’ distal roots and second molars’ mesial and distal roots, at a 4- and 8-mm distance from the cementoenamel junction. Intergroup comparisons were performed with analysis of variance and the Tukey test.
Results:
There was no statistically significant difference in the IZC bone thickness among the groups. For MBS bone availability, some comparisons revealed no difference; meanwhile, other comparisons revealed increased MBS bone thickness in the brachyfacial (first molars distal roots) and dolichofacial (second molars mesial and distal roots) patterns.
Conclusions
There was no significant difference in the IZC bone thickness among the groups. The facial skeletal pattern may affect the availability of ideal bone thickness for the insertion of extra-alveolar miniscrews in the MBS region; however, this variability is unlikely to be clinically meaningful.