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Background: Single-component adhesives do not require the application of a primer on the enamel surface that has been etched and has been reported to have acceptable shear bond strengths on in vitro evaluation. Aim: This split-mouth study aimed to examine and assess the rates of bracket bond failure of hydroxyethyl methacrylate (HEMA)-based (Aqualine LC) and bisphenol A-glycidyl methacrylate (BisGMA)-based (Orthofix SPA) single-component adhesives used to bond orthodontic brackets over 6 months. Materials and Methods: This in vivo study involved the participation of 50 adult subjects, with 1080 metallic brackets directly bonded to the labial/facial surface in a split-mouth design. After 6 months of treatment, 49 patients with 490 brackets bonded using a HEMA-based adhesive and 490 brackets bonded using a BisGMA-based adhesive were evaluated for bracket bond failures. Descriptive statistics and chi-square tests were done to compare the results. Results: The overall bracket bond failure rate (BFR) with single-component adhesives was 6.02%. Bracket BFRs of HEMA-based and BisGMA-based adhesives were 4.16% and 7.8%, respectively, and the difference was statistically significant (P < 0.05). Significant differences in BFRs between maxillary teeth (4.28%) and mandibular teeth (7.75%) were noted (P < 0.05). No significant differences in bond failures between either side or region were noted. Conclusion: Bond failures were more in brackets bonded with BisGMA-based adhesive (Orthofix SPA) compared with HEMA-based adhesive (Aqualine LC). Bond failures were less in the maxillary arch.
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Introduction Evaluating craniofacial growth is an essential component of orthodontic treatment, and it is assessed by examining the cranial base. The anterior cranial base is regarded as a stable structure, and the frontal sinus is also recognised as a contributing component in the formation of the cranial base. The frontal sinus, a cavity present in the frontal bone, displays variation in both size and shape and has an impact on the overall structure of the skull and face. This study aims to evaluate the impact of vertical skeletal pattern and gender on the volume of the frontal sinus. Materials and methodology In this study, 90 cone beam computed tomography (CBCT) scans from the record's section were included, comprising 46 males (55.44%) and 44 females (48.88%) aged 20 to 35 undergoing orthodontic treatment. The assessment involved evaluating vertical skeletal patterns using a lateral cephalogram derived from the CBCT scans, and volumetric analysis of the frontal sinus was conducted using Dolphin Imaging software (version 11.9; Dolphin Imaging and Management Solutions, Chatsworth, California). Statistical analysis was performed on the collected data using SPSS software, version 20.0 (IBM Corp., Armonk, NY). Pearson correlation, a one-way ANOVA test to determine any statistically significant differences between the means of both frontal sinus volume and cranial base length groups individually and an independent t-test to compare the sample means between the frontal sinus volume and cranial base length groups were performed. Results: A non-significant association was observed between frontal sinus volume and cranial base length in skeletal open bite (p = 0.73) and skeletal deep bite (p = 0.12) between males and females, which implies there is no substantial association between frontal sinus volume (p = 0.08) and cranial base length (p = 0.41) in the different vertical skeletal patterns. Conclusion: Frontal sinus volume was similar in subjects with a skeletal open bite and a deep bite. Males and females did not show a difference in frontal sinus volume. Hence, it was concluded that frontal sinus volume and anterior cranial base cannot be used as parameters to predict vertical malocclusions.
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Introduction Nanoparticles (NPs) have been widely used for biomedical applications. Various methods of synthesis of NPs have been performed and the sol-gel technique is one of the most common and feasible methods. ZnO and SnO2 NPs are widely used due to their interesting properties and versatile medical applications. The present study aimed to synthesize a composite of ZnO- SnO2 NPs and evaluate its structural, morphological, and antibacterial properties. Materials and methods ZnO-SnO2 NPs were prepared via the sol-gel technique. The morphological study was performed by scanning electron microscopy (SEM) imaging, the structural study was performed by X-ray diffraction (XRD) analysis, and chemical studies were performed by Fourier transform infrared spectroscopy (FT-IR) and energy-dispersive X-ray spectroscopy (EDAX). Antibacterial properties of the NPs were assessed by the agar diffusion test and the area of bacterial growth that was inhibited was measured under high and low concentrations of the NPs. Results The SEM analysis confirmed the irregular shape and elemental composition of the synthesized NPs. The purity of the NPs was confirmed by the EDAX spectrum, which indicates the weight percentages of the elements in the NPs as follows: Sn-53.8%, Zn-12.5%, O-29.1%, and C-4.7%. The chemical bonds between the NPs were confirmed by Fourier transform infrared spectroscopy. XRD analysis confirmed the high degree of crystallinity of the NPs and orthorhombic structure of SnO2 and the hexagonal structure of ZnO. The zone of inhibition against S. aureus, S. mutans, and E. coli for low concentrations of the NPs was 24 mm, 26 mm, and 30 mm and for high concentrations of the NPs it was 26 mm, 28 mm, and 31mm and these values were similar to the control antibiotics. Conclusion ZnO- SnO2 NPs were successfully prepared by the sol-gel method. The presence of NPs was confirmed and successfully characterized. The prepared NPs had a good antimicrobial effect against the tested pathogens.