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1.
J Adhes Dent ; 23(4): 357-365, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34269546

RESUMO

PURPOSE: This study evaluated whether active application of self-etching adhesives would influence their microtensile bond strength (µTBS) to dentin cut with burs of different grit sizes. MATERIALS AND METHODS: Eighty-four human premolars were divided into 12 groups according to 1) two dentin surface preparations with either superfine- or regular-grit diamond burs; 2) three adhesives - Clearfil SE Bond 2 (SE2), Scotchbond Universal (SBU, 3M Oral Care) and G-Premio Bond (GPB, GC); and 3) two application modes of each adhesive (active or passive). Six bonded teeth per group were sectioned into sticks for µTBS testing. Statistical analyses were performed using 3-way ANOVA followed by Duncan's test (p < 0.05). Additional teeth were prepared to observe the interaction between the dentin smear layer obtained from each bur with adhesives under different application modes using transmission electron microscopy (TEM). RESULTS: Active application significantly increased the dentin bond strength of SE2, irrespective of the kind of bur used (p < 0.05). The highest bond strength of SBU was observed when bonded to superfine-grit diamond bur-cut dentin with the active application. There was, however, no influence of the tested factors on GPB group (p > 0.05). TEM observation showed that active application promoted dentin smear layer dissolution in all adhesive groups. CONCLUSIONS: Bond strengths of self-etching adhesives to dentin are influenced by bur-cut smear layers and mainly by application mode of adhesive materials. Active application improves µTBS of self-etching adhesives by enhancing smear layer modification and resin penetration into bur-cut dentin.


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos , Resinas Compostas , Cimentos Dentários , Dentina , Humanos , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície , Resistência à Tração
2.
J Radiat Res ; 62(3): 483-493, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33899102

RESUMO

We developed a confidence interval-(CI) assessing model in multivariable normal tissue complication probability (NTCP) modeling for predicting radiation-induced liver disease (RILD) in primary liver cancer patients using clinical and dosimetric data. Both the mean NTCP and difference in the mean NTCP (ΔNTCP) between two treatment plans of different radiotherapy modalities were further evaluated and their CIs were assessed. Clinical data were retrospectively reviewed in 322 patients with hepatocellular carcinoma (n = 215) and intrahepatic cholangiocarcinoma (n = 107) treated with photon therapy. Dose-volume histograms of normal liver were reduced to mean liver dose (MLD) based on the fraction size-adjusted equivalent uniform dose. The most predictive variables were used to build the model based on multivariable logistic regression analysis with bootstrapping. Internal validation was performed using the cross-validation leave-one-out method. Both the mean NTCP and the mean ΔNTCP with 95% CIs were calculated from computationally generated multivariate random sets of NTCP model parameters using variance-covariance matrix information. RILD occurred in 108/322 patients (33.5%). The NTCP model with three clinical and one dosimetric parameter (tumor type, Child-Pugh class, hepatitis infection status and MLD) was most predictive, with an area under the receiver operative characteristics curve (AUC) of 0.79 (95% CI 0.74-0.84). In eight clinical subgroups based on the three clinical parameters, both the mean NTCP and the mean ΔNTCP with 95% CIs were able to be estimated computationally. The multivariable NTCP model with the assessment of 95% CIs has potential to improve the reliability of the NTCP model-based approach to select the appropriate radiotherapy modality for each patient.

3.
J Prosthet Dent ; 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33468316

RESUMO

STATEMENT OF PROBLEM: Anterior tooth selection is an important step in complete denture treatment as it plays a pivotal role not only in esthetics but also in mastication and pronunciation. However, conventional methods for tooth selection are not well established and rely on facial measurements and proportions, which vary among different ethnicities. PURPOSE: The purpose of this clinical study was to investigate the relationship between interalar width and intercanine distance and to compare different clinical methods for determining the position of the canine tooth. MATERIAL AND METHODS: Two hundred Thai participants (100 men and 100 women) aged 18 to 25 years with 6 full maxillary anterior teeth were enrolled in this study. The interalar width and intercanine distance were measured with digital vernier calipers and compared by using the paired-samples t test. To determine the canine position, 2 reference lines-the alar line (A line) and the inner canthus of the eye to alar line (IA line)-were drawn through the canine on both sides. The horizontal distances from each reference line to the canine cusp tip and distal contact point were evaluated and then analyzed using the 1-sample t test. RESULTS: All measurements were significantly different between men and women (P<.01). Interalar width was greater than intercanine distance in both sexes. In men, the A line coincided with the canine distal contact point (P>.05). In contrast, the IA line was distal to the canine distal contact point by 3.5 ±3.6 mm on the left side and by 3.9 ±3.4 mm on the right side. In women, the A line was situated between the canine cusp tip and distal contact point. It was mesial to the distal contact point by 2.0 ±2.0 mm on the left side and by 1.8 ±2.0 mm on the right side. The IA line was distal to the canine distal contact point by 1.2 ±2.6 mm on the left side and by 1.6 ±2.7 mm on the right side. CONCLUSIONS: The interalar width is greater than the intercanine distance in both sexes. The A line is more clinically relevant than the IA line for predicting canine position. The A line can directly determine the distal contact point of the canine in edentulous male patients. However, in women, a distance of approximately 2 mm should be added distal to the A line to locate the distal contact point of the canine on both sides.

4.
Head Neck Pathol ; 15(2): 408-415, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32720035

RESUMO

Enhancer of zeste homolog 2 (EZH2), a component of the polycomb repressive complex 2 that catalyzes trimethylation of H3K27 (H3K27me3), has been shown to promote tumor development and progression. Expression of EZH2 is associated with cell cycle regulation and cell proliferation in various neoplasms. Oral verrucous hyperplasia (OVH) and Oral verrucous carcinoma (OVC) are rare entities and share several clinical and histopathologic features. Problems distinguishing these lesions are added by a lack of adjacent normal tissue of the biopsy samples and poorly oriented tissue sections. The aim of this study was to investigate the expression of EZH2 and H3K27me3 in OVH and OVC and comparing the expression with normal oral mucosa and oral squamous cell carcinoma (OSCC). Seventy-eight samples, including 25 cases of OVC, 8 cases of OVH, 35 cases of OSCC and 10 cases of normal oral mucosa, were retrieved and submitted for immunohistochemical staining. The results demonstrated that the mean labeling indices (LIs) of EZH2 and H3K27me3 expression were highest in OSCC, followed by the OVC, OVH, and normal mucosa. Statistical differences in EZH2 LI were observed among these lesions whereas H3K27me3 LI was significantly different among OSCC, OVH and normal mucosa. EZH2 LI was found to have a sensitivity of 72.00% and specificity of 87.50% in distinguishing OVH from OVC, and a sensitivity of 57.14% and specificity of 84.00% in distinguishing OVC from OSCC. A positive correlation between EZH2 and H3K27me3 expression was significantly found in OVC but not in OVH and OSCC. These findings highlight the involvement of epigenetic regulation by EZH2-mediated H3K27me3 in the pathogenesis of OVH and OVC, and EZH2 expression indicates disease progression of these verrucous lesions. Diagnostic test analysis further suggests that EZH2 may be used as an additional test for differentiating OVH from OVC in questionable cases.

5.
Int J Paediatr Dent ; 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33220141

RESUMO

BACKGROUND: Bonding before sealant application enhances retention on saliva-contaminated sound teeth; however, there are few studies of bonding's efficacy on sealant retention on occlusal caries. AIM: To evaluate a bonding agent's efficacy on sealant retention on occlusal caries and caries transition. DESIGN: One hundred twenty pairs of first permanent molars with occlusal caries (ICDAS 2-4) from 98 children aged 7.3-9.9 years were included. One molar was randomly selected to use bonding (Adper™ Single Bond 2, 3M ESPE) applied before sealant application (Helioseal® clear, Ivoclar Vivadent). Bonding was not used on the contralateral tooth. Retention was determined using Simonsen's criteria; caries transition was evaluated using ICDAS scores, DIAGNOdent values, and bitewings at baseline, 6, 12, and 24 months. Data were analyzed with McNemar's and Fisher's exact tests. RESULTS: Bonding agent use significantly increased sealant retention rates (P < .001). Bonded (B) sealants had a higher retention rate (83.3%) than non-bonded (NB) sealants (53.7%). The difference in the caries-transition rate was not significant between the groups (P > .05). Three teeth (1.4%; NB:B = 2:1) were restored due to radiographic dentin-caries progression. CONCLUSIONS: Using a bonding agent before applying sealant on permanent molar occlusal caries (ICDAS 2-4) significantly enhanced sealant retention. Caries progression was rarely detected at the 24-month follow-up.

6.
J Int Soc Prev Community Dent ; 10(4): 415-423, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042882

RESUMO

Objectives: The aim of this study was to evaluate toothbrushing effectiveness in children with mild and moderate levels of severity of autism spectrum disorder (ASD) after using visual pedagogy. Materials and Methods: This quasi-experimental study was carried out with 30 children with ASD aged 5-17 years; 21 had mild ASD and 9 had moderate ASD. Informed consent and the subject's demographic information were obtained from caregivers. All subjects were then asked to show their toothbrushing practices, which were recorded by video. The toothbrushing ability, toothbrushing cooperation, and plaque index were evaluated before the study and at 2 weeks, 4 weeks, 3 months, and 6 months after visual pedagogy had been used. Results were analyzed by the Friedman test, Pearson's chi-square test, Fisher's exact test, and Mann‒Whitney U test. Results: Toothbrushing ability was significantly improved at all periods of follow-up. Toothbrushing cooperation and the dental plaque index were significantly better than before the study at 4 weeks, 3 months, and 6 months of follow-up. The toothbrushing ability of subjects with mild ASD was significantly better than that of subjects with moderate ASD at 4 weeks and 6 months of follow-up. The toothbrushing cooperation of the mild group was significantly better than that of the moderate group at 2 weeks, 4 weeks, and 3 months. There was no statistically significant reduction in the plaque index between the two groups. Conclusion: Visual pedagogy is useful for improving toothbrushing effectiveness in children with mild or moderate severity ASD. However, children with moderate severity ASD take longer to improve.

7.
Int J Paediatr Dent ; 30(4): 505-513, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32011037

RESUMO

BACKGROUND: Sensory over-responsivity (SOR) is common in autistic spectrum disorder (ASD), and it leads to a more intense response to sensory stimuli. AIM: To compare toothbrushing cooperation at home and in a dental office between SOR and sensory not over-responsivity (SNOR) children with ASD. DESIGN: This cross-sectional observational study was conducted with 51 children with ASD aged 4-17 years. Caregivers assessed each subject's sensory response by completing a back-translation questionnaire listing eight sensitivities. Subjects who had three or more of the sensitivities were considered SOR subjects. Toothbrushing cooperation in the dental office was recorded on videos. Statistical analysis used the Spearman correlation coefficient, chi-square test, Fisher's exact test, and Mann-Whitney U test. RESULTS: SNOR subjects (n = 10) had significantly higher scores in toothbrushing cooperation at home and in the dental office than did SOR subjects (n = 41) (P < .05). Oral sensitivity was significantly associated with toothbrushing cooperation at home, whereas oral, light, sound, and touch (face) sensitivities were significantly correlated with toothbrushing cooperation in the dental office (P < .05). CONCLUSIONS: SOR subjects showed less toothbrushing cooperation than SNOR subjects both at home and in the dental office.


Assuntos
Transtorno do Espectro Autista , Escovação Dentária , Adolescente , Cuidadores , Criança , Pré-Escolar , Estudos Transversais , Humanos , Percepção , Inquéritos e Questionários
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