Mm In Depth Research Articles

Micro-shear bond strength of different calcium silicate materials to bulk-fill composite.

This study aimed to compare the micro-shear bond strength (µSBS) performances of two resin-based calcium silicate-based cement (CSC) (TheraCal PT and TheraCal LC), Biodentine, and two modified-MTA CSC materials (NeoMTA 2 and BioMTA+) to bulk-fill restorative material. Fifty 3D printed cylindrical resin blocks with a central hole were used (2 mm in depth and 4 mm in diameter). CSCs were placed in the holes (per each group n = 10) and incubated for 24 h. Cylindrical polyethylene molds (2 mm in height and diameter) were used to place the bulk-fill restorative materials on the CSCs and polymerize for 20 s. Then, all specimens were incubated for 24 h at 37 °C at a humidity of 100%. Specimen's µSBSs were determined with a universal testing machine. Data were analyzed with one-way ANOVA (Welch) and Tamhane test. Statistically higher µSBS was found for TheraCal PT (29.91 ± 6.13 MPa) (p < 0.05) respect to all the other materials tested. TheraCal LC (20.23 ± 6.32 MPa) (p > 0.05) reported higher µSBS than NeoMTA 2 (11.49 ± 5.78 MPa) and BioMTA+ (6.45 ± 1.89 MPa) (p < 0.05). There was no statistical difference among TheraCal LC, NeoMTA 2 and Biodentine (15.23 ± 7.37 MPa) and between NeoMTA 2 and BioMTA+ (p > 0.05). Choosing TheraCal PT as the pulp capping material may increase the adhesion and µSBS to the bulk-fill composite superstructure and sealing ability.

First report of brown rot caused by Monilia mumecola on Chinese plum (Prunus salicina) in Fujian, China.

Brown rot caused by Monilinia spp. (anamorph Monilia) is a common disease in stone fruits worldwide, but the species in different hosts or regions may vary. Monilia mumecola is a recently identified species, only reported in some regions. Although the pathogen has been found on plum in Yunnan, Hubei, and Zhejiang provinces, and Chongqing municipality in China (Yin et al. 2015), it has not been reported in southeast coast of China. In May 2022, brown rot with grey spores on fruit was observed in a plum orchard with 15% disease incidence in Sanming City, Fujian Province, located in southeast coast of China. Four single-spored isolates were obtained from germinating conidia on the water agar for further investigation. The colonies on potato dextrose agar (PDA) were initially white, gradually turned gray to brown, with lobbed margins and rare sporulation. Average mycelial growth rate ranged from 0.74 to 1.08 cm/day at 25 oC. Conidia were lemon-shaped or subglobose, hyaline, with an average size of 17.64 to 19.35×11.14 to 14.44 μm (n=30). Each isolate produced one to three or four germ tubes. Such characteristics are similar to M. mumecola (Yin et al. 2015). To confirm the identity of the isolates, genomic DNA was extracted and species-specific primers of Hu et al. (2011) were used to amplify the 712 bp sequence. In addition, the ITS region, partial genes of glyceraldehyde-3- phosphate dehydrogenase (GAPDH) and beta-tubulin (TUB2) were also amplified using primers sets ITS1/ITS4 (Glass and Donaldson 1995), Mon-G3pdhF/Mon-G3pdhR and Mon-TubF1/ Mon-TubR1, respectively (Hu et al. 2011). Sequences obtained for those three regions were 478, 762 and 1527 bp, respectively. Each region of all four isolates was identical, so one sequence for each region was submitted to GenBank with accession numbers OQ207672, OQ225251 and OQ225252, respectively, which had 100% identity with M. mumecola HQ908786 (ITS), HQ908784 (GAPDH), and HQ908775 (TUB2) using BLAST analysis in NCBI database, respectively. Pathogenicity was conducted with mycelium plugs from the edge of 7-day-old colony on three mature 'Angeleno' plums fruit (Prunus salicina) creating nine inoculations with three wounds per fruit, and each wound was 5 mm in diameter and 2 mm in depth. The same amount fruit and wounds inoculated with PDA plugs without fungi were used as a control. Brown rot symptoms were observed on all inoculated plums 4 days post-inoculation under room temperature with 100% humidity, whereas control plums remained symptomless. Fungal colonies re-isolated from the lesions showed the same morphological features as the original isolate , thus fulfilling Koch's postulates. To our knowledge, this is the first report of M. mumecola on plum in Fujian Province of China. The findings in this studies have important management implications for local plum growers because more than one Monilia species have been reported, where only M. fructicola was present in this region.

Planning Queen Elizabeth II’s Visit to Bondi Beach in 1954

Planning Queen Elizabeth II’s Visit to Bondi Beach in 1954

Tool Health Monitoring of a Milling Process Using Acoustic Emissions and a ResNet Deep Learning Model

In the industrial sector, tool health monitoring has taken on significant importance due to its ability to save labor costs, time, and waste. The approach used in this research uses spectrograms of airborne acoustic emission data and a convolutional neural network variation called the Residual Network to monitor the tool health of an end-milling machine. The dataset was created using three different types of cutting tools: new, moderately used, and worn out. For various cut depths, the acoustic emission signals generated by these tools were recorded. The cuts ranged from 1 mm to 3 mm in depth. In the experiment, two distinct kinds of wood-hardwood (Pine) and softwood (Himalayan Spruce)-were employed. For each example, 28 samples totaling 10 s were captured. The trained model's prediction accuracy was evaluated using 710 samples, and the results showed an overall classification accuracy of 99.7%. The model's total testing accuracy was 100% for classifying hardwood and 99.5% for classifying softwood.

Comparison of Diagnostic Accuracy of 2 Cone Beam Computed Tomography System (Newtom &amp;Planmeca) for Detection of External Root Resorption in Vitro

Introduction: External root resorption is a clinical problem that is difficult to diagnose, therefore radiographic examination is important for diagnose. The purpose of this study was comparing the diagnostic accuracy of 2 Cone Beam Computed Tomography in detecting of external root resorption, in vitro.Materials &amp; Methods: This study was done on 48 single-rooted teeth. Cavities of 0.3, 0.2 and 0.15 mm in depth with round bur 0.3 mm were drilled on buccal and lingual surfaces in the cervical, middle and apical thirds of some of roots. Then CBCT were taken and 4 observers assessed the scans. Sensitivity, specificity and Kappa value were determined. The statistical analysis was performed with the Z-test (p value &lt; 0.05).Results: In comparison of the accuracy, sensitivity and specificity of the two devices, there was no significant difference. In the apical, middle and cervical as well as at various depths there was no significant difference between the two devices, but in the numerical point of view, the sensitivity for both devices in the midsection, was in the highest amount. The highest value for the specificity is related to the apical region. For both devices, the sensitivity level GBJ, by increasing the depth. The lowest agreement between observers was 0.61. The highest agreement rate was in the middle section and the least amount of agreement was related to the apical region.Conclusion: CBCT brand type is not effective factor in the detection of external root resorption. The location and depth of external root resorption can be effective factors in diagnostic accuracy.

Rapid beamforming of ultrasound chirp signals in frequency domain using the chirp scaling algorithm

Linear frequency-modulated (chirp) transmits have been used successfully in the past to increase penetration depth of ultrasound signals in tissue and to improve the signal-to-noise ratio (SNR) in the resulting ultrasound images. However, beamforming chirp signals using delay-and-sum (DAS) can be slow on systems without a GPU. We propose using the chirp scaling algorithm (CSA), originally developed for synthetic aperture radar, as a faster alternative to DAS on CPU that results in similar image quality, especially at larger depths. To perform preliminary comparisons of the beamforming methods, we simulated in FIELD II monostatic synthetic aperture data containing point targets up to 300 mm in depth. The simulation accounted for average signal attenuation in soft tissue of 0.5 dB per MHz per cm. We analyzed the point spread functions and the runtimes of the methods in MATLAB with a single CPU. Beamformed point targets above 80 mm depth had almost identical sidelobe levels and full-width-at-half-maximum between the two methods, while the median runtime for CSA was 9.3 times faster than for DAS. We further extend CSA to multistatic acquisitions with chirp transmits and with curvilinear arrays for more clinical applicability and improved image quality.

Abstract P590: Clinical Significance of Nonspecific T-Wave Abnormalities on Electrocardiogram

Background: The electrocardiogram (ECG) is a tool to effectively evaluate for coronary heart disease (CHD). Clinicians seek out major ST/T changes as key indicators of myocardial infarction/ischemia. However, subtle T wave abnormalities which are less than 2 mm in depth are termed “nonspecific” or “borderline” and are often considered incidental. These findings have been previously reported to be associated with both CHD and cardiovascular disease mortality. CHD manifests in many different populations; therefore, it is vital to study the association of nonspecific T wave changes and ischemic heart disease in different genders, age groups, and ethnicities to determine if there is clinical significance of this finding. If so, this may serve as a prognostic factor for cardiac disease which may warrant the need for earlier CHD evaluation by stress test, echocardiogram, or cardiac catheterization. Prior observation from this group does not show any race or gender difference in EF in the general population. Methods: ECGs performed at a university-affiliated hospital from January 2015 to March 2015 were downloaded from ECG Intellispace software and analyzed for the presence of “nonspecific T” and “borderline T” abnormalities in order to determine their clinical significance. Patient encounters corresponding to these ECG findings were analyzed for age, gender, BMI, hypertension (HTN), diabetes, and history of smoking, in addition to documentation of available stress testing, cardiac catheterization (cath), and echocardiographic ejection fraction (EF) results. Ejection fraction analysis was compared amongst subgroups of patients divided by age, gender, and race by calculating the average EF and standard deviation along with performing student-t test and ANOVA. Results: Out of 2825 ECGs analyzed, there were 582 encounters (20.6%) with nonspecific T wave abnormalities, out of which 247 had documented EFs, and only 47 documented stress tests and 58 documented caths. Average age and BMI is 52.2 ± 16.1 years and 30.6 ± 9.12 kg/m2, respectively. The prevalence of HTN, diabetes, and smoking was 63.4%, 26.7%, and 43.8%, respectively. EFs (%) among WMs, WFs, AAMs, and AAFs were 54.7 ± 12.7, 57.1 ± 14.2, 51.6 ± 16.3, 58.2 ± 12.6, respectively (P = 0.03 by ANOVA, mostly contributed by the low EF in AAM). The stress test and cath numbers were too small to conduct a meaningful statistical analysis. Conclusion: Significantly lower EF in AAM was found compared with other gender and race subgroups. The reason for this finding is not clear; however, ischemia cannot be excluded since analysis for correlation between ECG finding of nonspecific T wave abnormalities and CHD was limited by the small number of stress tests and caths available. This finding was not previously reported in the literature, but is of paramount importance in considering EF evaluation in AAM with nonspecific T wave abnormalities by ECG.

Real-time detection of barely visible defects on composite structures based on surface reconstruction

Visual inspection is currently the most common way for surface defect detection in the damaged composite structure, which is considered unreliable for barely visible impact defects (BVIDs) of less than 0.3 mm in depth. This paper proposes a defect detection method using stereo vision-based surface reconstruction and curvature analysis, which can detect defects of less than 0.1 mm in depth. To meet the real-time requirement of on-site detection, a real-time image registration algorithm is proposed through deformation decomposition and deep learning-based image correlation, realizing 1 frame/s calculation speed for megapixel images. The detection experiments of barely visible defects on carbon fiber-reinforced plastic (CFRP) composite laminates are carried out to demonstrate the effectiveness and efficiency. The proposed method presents a low-cost and high-efficiency approach for non-destructive testing and health monitoring of composite structures.

Micro-Sized Pinhole Inspection with Segmented Time Reversal and High-Order Modes Cluster Lamb Waves Based on EMATs

Pinhole corrosion is difficult to discover through conventional ultrasonic guided waves inspection, particularly for micro-sized pinholes less than 1 mm in diameter. This study proposes a new micro-sized pinhole inspection method based on segmented time reversal (STR) and high-order modes cluster (HOMC) Lamb waves. First, the principle of defect echo enhancement using STR is introduced. Conventional and STR inspection experiments were conducted on aluminum plates with a thickness of 3 mm and defects with different diameters and depths. The parameters of the segment window are discussed in detail. The results indicate that the proposed method had an amplitude four times larger than of conventional ultrasonic guided waves inspection method for pinhole defect detection and could detect micro-sized pinhole defects as small as 0.5 mm in diameter and 0.5 mm in depth. Moreover, the segment window location and width (5−10 times width of the conventional excitation signal) did not affect the detection sensitivity. The combination of low-power and STR is more conducive to detection in different environments, indicating the robustness of the proposed method. Compared with conventional ultrasonic guided wave inspection methods, the proposed method can detect much smaller defect echoes usually obscured by noise that are difficult to detect with a lower excitation power and thus this study would be a good reference for pinhole defect detection.

Size effect of large high strength concrete beams with or without shear reinforcement

This paper presents a research programme conducted on a total of seven large high strength concrete (HSC) beams, up to 1800 mm in depth and 13400 mm in span, with and without shear reinforcement in the web. This study investigates experimentally the effects of aggregate size, shear reinforcement ratio, and effective depth on shear strength of large HSC beams. In addition, the test data are adopted for verification of design provisions in ACI 318–14, ACI 318–19 and EN 1992–1-1. It is experimentally shown that reduction in ultimate shear strength was observed with increasing beam depth, regardless of the maximum aggregate size and web reinforcement ratio. A larger beam depth led to a more extensive development of flexural and shear cracks, as well as a greater beam stiffness. Besides, the use of smaller aggregates results in a higher ultimate strength (in MPa) for the beams. Shear equations from ACI 318–14 overestimated shear strengths of the large HSC beams without web reinforcement, while ACI 318–19 and EN 1992–1-1 predictions were more conservative by accounting for the size effect term. It is also shown that the existing codes of practice could not account for the effect of aggregate size when determining shear strength. Additionally, predictions by all the three codes for the HSC beams with minimum shear reinforcement were generally conservative.

The association of psoriasis and psoriatic arthritis with periodontitis: A hospital-based case-control study.

Background Periodontitis can trigger and perpetuate inflammation in several chronic inflammatory diseases. The association of periodontitis with psoriasis has been investigated earlier, but data are incomplete and the influence of confounders has not been fully evaluated. We examined the relationship of dental and periodontal health parameters in patients with psoriasis and/or psoriatic arthritis. Methods This hospital-based cross-sectional analytical study was conducted in patients with chronic plaque psoriasis, psoriatic arthritis or both, and compared with controls. Dental and periodontal health parameters were assessed based on the WHO oral health assessment method. Multivariate logistic regression was done on variables with significant or near-significant values to find the association between periodontitis and psoriasis and/or psoriatic arthritis after adjusting for confounders. Results Psoriasis and/or psoriatic arthritis were independently and significantly associated with periodontal pockets ≥4 mm in depth. Limitations Causality and temporal relationship cannot be established as this was a cross-sectional study. As in all observational studies, the possibility of unmeasured or unknown confounders exists. Psoriatic arthritis was present only in a small subset of patients. Conclusion Patients with psoriasis and/or psoriatic arthritis have significant periodontal inflammation. This needs to be addressed by dental examination and intervention.

The Capability of Cocoa Pulp Juice (Theobroma cacao L.) on Crown Dentin Smear Layer Removal

Introduction: smear layer is a thin layer formed from tooth structure instrumentation which can prevent the restoration material bonds the tooth structure. Partial smear layer should be removed using dentin conditioner. One of dentin conditioners that is often used is 10% polyacrylic acid. The natural ingredient that is thought to be an alternative to dentin conditioner is cocoa pulp juice because it contains many acidic compounds. Methods: This research is a laboratory experimental study to determine the ability of 100% cocoa pulp juice (Theobroma cacao L.) to remove the crown dentin smear layer and compare it to 10% polyacrylic acid. Eight dental elements were prepared for class I cavities on the middle 1/3 of buccal surface to reach 3 mm in diameter and 2 mm in depth, enamel was prepared until 1 mm in depth of cavity left. The samples were irrigated with sterile aquades and dried. Furthermore, 4 samples were applied 10% polyacrylic acid and 4 samples used cocoa pulp juice, left for 20 seconds, irrigated, dried, and put in the oven for 2x24 hours. The samples were examined for their cavity cleanliness score using Scanning Electron Microscope (SEM) photo with 2000x of magnification. Result: both groups have the same score and statistical test shows that there is no significant difference between them. Conclusion: the 100% cocoa pulp juice was able to clean the smear layer of crown dentin and its ability equal to 10% polyacrylic acid.

The efficacy of non-surgical platelet-rich fibrin application on clinical periodontal parameters and periostin level in periodontitis: Clinical trial.

Platelet-rich fibrin (PRF) has been widely used in regenerative dentistry due to many growth factors produced. Periostin, a matricellular protein, is a reliable marker for tissue regeneration. Periostin is part of the cellular matrix and regulates bone homeostasis. This study aims to explore the efficacy of PRF in improvement of the clinical periodontal parameters as an adjunct to the scaling and root planing and to evaluate periostin level in gingival crevicular fluid (GCF) at baseline, 1- and 3-month recall visits. Fourteen periodontitis patients who met the inclusion criteria were recruited in this study. Two contralateral periodontal pockets with 4-6 mm in depth in each patient were selected. The sites in every participant were randomly allocated into control sites or test sites. In control sites, only conventional scaling and root planing was carried out. In test sites, however, scaling and root planing method and PRF were applied. Periostin level in GCF and clinical periodontal parameters were measured. The test sites revealed greater relative attachment gain (2.614 ± 0.606 mm and 3.321 ± 0.668 mm) than control sites (1.285 ± 0.671 mm and 1.839 ± 0.632 mm) and a significant pocket reduction (2.535 ± 0.664 mm and 3.321 ± 0.668 mm) than the control sites (1.21 ± 0.508 mm and 1.892 ± 0.655 mm) at 1- and 3-month recall visits respectively. In the test sites, level of periostin (48.83 ± 9.3ng/μl and 98.90 ± 24.94 ng/μl) were greater than periostin levels in the control sites (42.65 ± 7.03 ng/μl and 49.29 ± 15.14 ng/μl) at 1- and 3-month recall visits respectively. In conclusion, the non-surgical application of PRF as an adjunct to scaling and root planing significantly improved the clinical periodontal parameters through raising periostin level in GCF.

Effect of contact force on pulsed field ablation lesions in porcine cardiac tissue.

Contact force has been used to titrate lesion formation for radiofrequency ablation. Pulsed field ablation (PFA) is a field-based ablation technology for which limited evidence on the impact of contact force on lesion size is available. Porcine hearts (n = 6) were perfused using a modified Langendorff set-up. A prototype focal PFA catheter attached to a force gauge was held perpendicular to the epicardium and lowered until contact was made. Contact force was recorded during each PFA delivery. Matured lesions were cross-sectioned, stained, and the lesion dimensions measured. A total of 82 lesions were evaluated with contact forces between 1.3and 48.6 g. Mean lesion depth was 4.8 ± 0.9 mm (standard deviation), mean lesion width was 9.1 ± 1.3 mm, and mean lesion volume was 217.0 ± 96.6 mm3 . Linear regression curves showed an increase of only 0.01 mm in depth (depth = 0.01 × contact force + 4.41, R2 = 0.05), 0.03 mm in width (width = 0.03 × contact force + 8.26, R2 = 0.13) for each additional gramof contact force, and 2.20 mm3 in volume (volume = 2.20 × contact force + 162, R2 = 0.10). Increasing contact force using a bipolar, biphasic focal PFA system has minimal effects on acute lesion dimensions in an isolated porcine heart model and achieving tissue contact is more important than the force with which that contact is made.

Effect of low temperature and room temperature on the depth of cure of bulk-fill composite resins

The study analyzed the influence of temperature on the depth of cure of bulk-fill composite resins. Three discs (ISO 4049/2000) from each group were made, and four restorative materials were investigated: Opus Bulk-Fill Flow, Opus Bulk-Fill APS, Filtek™ One Bulk-Fill, and Filtek™ Bulk-Fill Flow. They were light-cured (Gnatus ± 1,200 mW/cm2) for 20 seconds, varying the temperature (23°C and 5°C) and simulating the use of the product both at room temperature and under refrigeration. The materials were inserted in aluminum matrices with 10 mm in depth and 4 mm in diameter. A clear film strip and a glass microscope slide were positioned at the top and bottom surfaces. The material was condensed and light-cured with the tip of the light source in close contact, for 20 seconds on the top surface. Immediately after irradiation, the samples were removed from the mold, and the uncured part was removed with a plastic spatula. The measurement was performed with a micrometer ± 0.1 mm, and the value was divided by 2. The data were analyzed with two-way ANOVA at a significance of 0.05. There was a statistical difference in the temperature between the results obtained in Opus Bulk-Fill APS (p &lt;0.001) and Filtek™ Bulk-Fill Flow (p = 0.018) resins. For the temperature of 5°C, Filtek™ Bulk-Fill Flow showed a statistical difference compared to the other resins, while Opus Bulk-Fill Flow and Opus Bulk-Fill APS did not. For the temperature of 23°C, Filtek™ Bulk-Fill Flow maintained the statistical difference from the others, but Filtek™ One Bulk-Fill and Opus Bulk-Fill APS did not present statistical differences. Storing the Filtek™ Bulk-Fill Flow composite resin in the refrigerator caused a greater depth of cure than the other resins, and the depth of cure decreased at room temperature. As for Opus Bulk-Fill APS, the depth of cure decreased proportionally to the temperature decrease. The temperature may affect the depth of cure of some composite resins.

Detection, distinction, and quantification of pipeline surface and subsurface defects by DC magnetization scanning induction thermography

Pipelines are the backbone of the oil and natural gas industry. In order to guarantee its quality, DC magnetization scanning induction thermography (DCMSIT) is proposed to detect, distinguish and quantify the pipeline surface and subsurface defects. The exciting method, consisting of Helmholtz DC magnetization coils and a toroidal AC induction heating coil, is designed to adapt the pipeline’s annular shape and realize full coverage automatic detection. Under DC magnetization, surface and subsurface defects cause distorted permeability distribution in the skin layer relating to defect depth. Under AC magnetization, the distorted permeability produces abnormal thermal distribution, indicating the characteristics of defects. Based on the different thermal distributions in shapes and intensities of surface and subsurface defects, continuous wavelet transform (CWT) is used for thermal signal spatial-frequency analysis to distinguish surface and subsurface defects. The principle of the proposed method is analyzed based on Faraday’s law, Joule’s law, and thermal propagation. Then, finite element simulation is conducted to investigate magnetic permeability distribution for pipeline surface and subsurface defects with different depths. Finally, the DCMSIT system for pipelines is designed and developed to validate the proposed method. Experimental results show that the proposed method can evaluate pipeline surface and subsurface defects from 1.0 mm to 5.0 mm in depth.

How far the zone of heat-induced transient block extends beyond the lesion during RF catheter cardiac ablation

Purpose While radiofrequency catheter ablation (RFCA) creates a lesion consisting of the tissue points subjected to lethal heating, the sublethal heating (SH) undergone by the surrounding tissue can cause transient electrophysiological block. The size of the zone of heat-induced transient block (HiTB) has not been quantified to date. Our objective was to use computer modeling to provide an initial estimate. Methods and materials We used previous experimental data together with the Arrhenius damage index (Ω) to fix the Ω values that delineate this zone: a lower limit of 0.1–0.4 and upper limit of 1.0 (lesion boundary). An RFCA computer model was used with different power-duration settings, catheter positions and electrode insertion depths, together with dispersion of the tissue’s electrical and thermal characteristics. Results The HiTB zone extends in depth to a minimum and maximum distance of 0.5 mm and 2 mm beyond the lesion limit, respectively, while its maximum width varies with the energy delivered, extending to a minimum of 0.6 mm and a maximum of 2.5 mm beyond the lesion, reaching 3.5 mm when high energy settings are used (25 W–20s, 500 J). The dispersion of the tissue’s thermal and electrical characteristics affects the size of the HiTB zone by ±0.3 mm in depth and ±0.5 mm in maximum width. Conclusions Our results suggest that the size of the zone of heat-induced transient block during RFCA could extend beyond the lesion limit by a maximum of 2 mm in depth and approximately 2.5 mm in width.

Clinical performance of two onlay designs for molars after root canal treatment.

To evaluate the clinical performance of two proposed onlay designs. Molars with occlusal and/or mesial/distal defects after root canal treatment were classified by design into three groups. Onlays without shoulders were the control group (Group C, n = 50). The designed onlays were Group O (n = 50) and the designed mesio-occlusal/disto-occlusal onlays were Group MO/DO (n = 80). All onlays had an occlusal thickness of approximately 1.5-2.0 mm, and the designed onlays had a shoulder depth and width of approximately 1 mm. In Groups C and O, the box-shaped retention was 1.5 mm in depth. The proximal box was connected with a dovetail retention in Group MO/DO. Patients were examined every 6 months and followed for 36 months. Restorations were evaluated by using the modified United States Public Health Service Criteria. Statistical analysis was performed by using Kaplan-Meier analysis, the chi-square test, and Fisher's exact test. No tooth fracture, debonding, secondary caries, or gingivitis was observed in any group. Groups O and MO/DO had satisfactory survival and success rates, and there was no significant difference in performance characteristics among the three groups (P > 0.05). The two proposed onlay designs were effective in protecting molars.

Effect of Silver Nanoparticles of Herbal Origin on the Compressive and Push-out Bond Strengths of Mineral Trioxide Aggregate.

The purpose of this in vitro study was to investigate the effect of incorporating silver nanoparticles (AgNPs) of herbal origin into mineral trioxide aggregate (MTA) on the push-out bond strength (PBS) and compressive strength (CS) in simulated furcal area perforations. In this in vitro study, simulated furcal area perforations (1.3 mm in diameter and 2 mm in depth) were created in 40 extracted human lower molar teeth, which were divided into two groups (n=20): MTA alone and MTA combined with AgNPs (2% wt). Using a universal testing machine, PBS was evaluated by performing push-out tests, while CS was assessed using cylindrical specimens. The normal distribution of data was checked using the Kolmogorov-Smirnov test, and statistical analysis was performed using two-way ANOVA. The CS results showed no significant difference between the MTA group at 4 and 21 days (P=0.297), but a significant difference was observed in the nanosilver/MTA group (P=0.013). However, there was no significant difference in the push-out bond strength among the study groups (P>0.05). The incorporation of herbal origin silver nanoparticles did not significantly affect the PBS or CS of MTA.

Histopathological investigation of the effect of chitosan on oral mucous wound healing in experimentally established diabetic rats.

In our study, it was aimed to histopathologically investigate the effects of chitosan on wound healing in the oral mucosa by applying the gel form of experimentally induced diabetes mellitus. In our study, 42 male Sprague Dawley rats weighing 340±20 g, 14-16 weeks old, were used. Diabetes induction was achieved by administering 55 mg/kg streptozotocin intraperitoneally (i.p.) to 32 of the subjects. Those with blood glucose levels above 250 mg/dl as measured at the end of the 2nd and 7th days were considered diabetic and included in the study. Afterwards, a wound of 5 mm in diameter and 1 mm in depth was created in the buccal mucosa of the experimental animals with a disposable punch biopsy tool. Wound healing was evaluated on the 2nd and 5th days after the surgical operation. The samples were evaluated histopathologically in terms of inflammation, fibrosis, epithelial regeneration, necrosis, and foreign body reaction. As a result of the statistical analysis, a significant difference was found between the groups in terms of inflammation levels on the 2nd and 5th days (p<0.05). In the intragroup evaluations, the rate of severe inflammation on the 2nd day in the diabetes+chitosan group was found to be statistically significantly higher than the 5th day (p<0.05). While there was no statistically significant difference between the groups in terms of fibrosis levels on the 2nd day (p>0.05), a statistically significant difference was found in terms of fibrosis levels on the 5th day (p<0.05). It was observed that chitosan did not cause foreign body reaction in any of the groups on the 2nd and 5th days.