Effect of Different Isolation Methods on Bioaerosol Distribution: An In Vitro Study.

Purpose: The purposes of this in vitro study were to evaluate the effect of three isolation methods to mitigate bioaerosols during stainless steel crown (SSC) preparations and assess the distribution of Streptococcus mutans by aerosolization in closed-room operatories. Methods: Melamine teeth coated in laboratory-grown S. mutans biofilm were prepared for SSCs using three different isolation methods. Agar plates were placed in five locations throughout the operatory and opened during each preparation as well as for 10 minutes immediately following to collect aerosolized S. mutans. Bacterial colonies were counted after incubating plates for 48 hours. Data were analyzed for differences between the isolation method and plate locations. Results: Bacterial colony counts for teeth prepared using high-volume evacuation suction (HVE) with dental dam (DD) isolation were statistically significantly higher than for those prepared using HVE with a DryShield®(DS) and HVE with no isolation at the assistant (A) (P<0.001), operator face shield (FS) (P<0.001), and patient (Pt) (P=0.002) locations. No significant differences were found among isolation methods for parent (Pa) or rear delivery (RD) locations. The location that produced the most bacterial colony counts using HVE with DD isolation was FS (P<0.001), followed by A (P=0.04), Pt (P<0.001), and RD and Pa (P<0.001). Counts produced from teeth prepared with DS isolation were significantly higher at the Pt location than the A (P<0.001), FS (P=0.002), RD (P<0.001), and Pa (P=0.008) locations. Conclusion: The use of dental dam with high-volume evacuation suction during stainless steel crown preparations increased bioaerosols near the procedure, while dental evacuation systems (DryShield®) may effectively limit their spread.

Comparing Shear Bond Strength Between Pink Opaquer and Other Tooth-Colored Restorative Materials on Demineralized Dentin Treated with Silver Diammine Fluoride.

Purpose: The purposes of this study were to evaluate the effect of silver diammine fluoride (SDF) on the shear bond strength (SBS) of pink opaquer (PO) compared to resin-modified glass ionomer (RMGI) and conventional composite (COMP) on demineralized dentin, and also to investigate the mode of failure (MOF). Methods: Sixty extracted third molars were prepared, demineralized for 14 days, and divided into four groups: (1) COMP; (2) SDF+PO; (3) SDF+RMGI; and (4) SDF+COMP (restoration size: two by two mm). SBS, MOF, modified adhesive remnant index (MARI), and remnant adhesive volume (RAV) were evaluated using an Instron® machine, light microscopy, 3D digital scanner ( 3Shape©), and GeoMagic Wrap© software. Results: There was no significant difference in SBS (MPa) among the COMP mean??standard deviation (2.5±1.59), SDF+COMP (2.28±1.05), SDF+PO (3.31±2.63), and SDF+RMGI groups (3.74±2.34). There was no significant difference in MOF and MARI among the four groups (P>0.05). There was no significant difference in RAV (mm3) among the COMP (0.5±0.33), SDF+COMP (0.39±0.44), SDF+PO (0.42±0.38), and SDF+RMGI groups (0.42±0.38; P>0.05). A significant correlation existed between MOF and RAV (R equals 0.721; P<0.001). MOF, MARI, and RAV did not show any correlations with SBS (P>0.05). Conclusions: Silver diammine fluoride does not affect shear bond strength between carious dentinal surface and tooth color restorative materials. The amount of material left on the interface is not related to the amount of shear force needed to break the restoration.

Study on the disinfection effect of chlorine dioxide disinfectant (ClO2) on dental unit waterlines and its in vitro safety evaluation.

BACKGROUND: Ensuring the safety of dental unit waterlines (DUWLs) has become a pivotal issue in dental care practices, focusing on the health implications for both patients and healthcare providers. The inherent structure and usage conditions of DUWLs contribute to the risk of biofilm formation and bacterial growth, highlighting the need for effective disinfection solutions.The quest for a disinfection method that is both safe for clinical use and effective against pathogens such as Staphylococcus aureus and Escherichia coli in DUWLs underscores the urgency of this research. MATERIALS: Chlorine dioxide disinfectants at concentrations of 5, 20, and 80 mg/L were used to treat biofilms of S. aureus and E. coli cultured in DUWLs. The disinfection effectiveness was assessed through bacterial counts and culturing. Simultaneously, human skin fibroblast cells were treated with the disinfectant to observe changes in cell morphology and cytotoxicity. Additionally, the study included corrosion tests on various metals (carbon steel, brass, stainless steel, aluminum, etc.). RESULTS: Experimental results showed that chlorine dioxide disinfectants at concentrations of 20 mg/L and 80 mg/L significantly reduced the bacterial count of S. aureus and E. coli, indicating effective disinfection. In terms of cytotoxicity, higher concentrations were more harmful to cellular safety, but even at 80 mg/L, the cytotoxicity of chlorine dioxide remained within controllable limits. Corrosion tests revealed that chlorine dioxide disinfectants had a certain corrosive effect on carbon steel and brass, and the degree of corrosion increased with the concentration of the disinfectant. CONCLUSION: After thorough research, we recommend using chlorine dioxide disinfectant at a concentration of 20 mg/L for significantly reducing bacterial biofilms in dental unit waterlines (DUWLs). This concentration also ensures satisfactory cell safety and metal corrosion resistance.

Role of preservation methods using deep-freezing and liquid nitrogen in bone allograft characteristics: An in vitro study.

Bone grafting has emerged as a key solution in bone defect management such as allograft, graft of bone from another individual. However, bone allografts usually undergo rigorous preparation to eliminate immune-triggering elements. The deep-freezing methods may delay graft use, while cryopreservation using liquid nitrogen allows rapid freezing but may alter graft characteristics. The aim of this study was to investigate the post-preservation changes in bone allograft characteristics and to compare the effectiveness of deep-freezing and liquid nitrogen methods using animal model. An experimental study using a post-test only control group design was conducted. Fresh-frozen femoral cortical bone was obtained from male New Zealand white rabbits. Preservation by deep-freezing involved placing bone samples in a -80°C freezer for 30 days. For liquid nitrogen preservation, bone grafts were immersed in liquid nitrogen for 20 min, followed by a 15-min rest at room temperature and a final immersion in 0.9% sodium chloride at 30°C for 15 min. Bone samples then underwent evaluation of cell viability, compression, and bending tests. Cell viability test employed the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and the compression and bending tests used the Universal Testing Machine (UTM). Independent Student t-test or Mann-Whitney U test were used to compare the methods as appropriate. Our study found that the use of deep-freezing and liquid nitrogen resulted in similar outcomes for cell viability, compression, and bending tests, with p-values of 0.302, 0.745, and 0.512, respectively. Further exploration with larger sample sizes may help to optimize the methods for specific applications.

Cone-beam computed tomography evaluation of shaping ability of kedo-S square and fanta AF™ baby rotary files compared to manual K-files in root canal preparation of primary anterior teeth.

BACKGROUND: Pediatric rotary file systems were developed to solve manual file limitations. With many systems available, it may be tricky to select the most appropriate one. AIM: to assess & compare Kedo-S Square, Fanta-AF™-Baby rotary files with manual K-file concerning removed dentin amount, canal transportation, centric ability & root canal taper using CBCT in primary anterior teeth. DESIGN: Extracted Seventy-five upper primary anterior teeth with intact 2/3 root length were collected and divided into three groups based on root canal instrumentation, group-I: prepared using K-file, group-II: prepared using Kedo-S Square, and group-III: prepared using Fanta AF™ Baby file. The teeth were imaged with CBCT before & following canal instrumentation. Then, the removed dentin amount was calculated at each root-canal level. The Kruskal-Wallis test was utilized to statistically analyze study data. RESULT: The difference among the three groups was highly statistically significant at cervical & apical thirds concerning dentin thickness changes on both mesial & distal sides following canal preparation with the least removed dentin in the Kedo-S Square group(P < 0.0001). Regarding transportation & centering ability, a non-significant difference between the three groups was found. 80% of the Fanta AF™ Baby group had good-tapered preparation compared to the Kedo-S Square (72%) and K-file (40%) groups(P < 0.05). CONCLUSION: Kedo-S Square was preferable to Fanta-AFTM-Baby & manual K-files in primary root canal preparation.

A conservative approach to localize loose implant screw through cemented crown: an in vitro experimental study.

BACKGROUND: Retrieval of cement-retained implant-supported restorations is intriguing in cases of screw loosening. Detecting the estimated size of the screw access hole (SAH) could decrease destruction to the prosthesis and preserve the crown. OBJECTIVES: To precisely localize loose implant screws through cemented crowns to reduce crown damage after screw loosening. MATERIALS AND METHODS: In this in vitro study, 60 cement-retained implants supported 30 zirconia-based, and 30 ceramics fused to metal (CFM) lower molar crowns were invented, and each was subdivided into three subgroups (10 each). In group I (AI/BI) (control), SAH was created with the aid of orthopantomography (OPG). In contrast, in group II (zirconia-crown), SAH was created with the aid of CBCT + 3D printed surgical guide with a 2 mm metal sleeve in subgroups IIA/IIIA and CBCT + MAR was used to develop SAH in subgroups IIB/IIIB. SEM and Micro-CT scanned the SAH openings to determine the diameter of the hole, cracking, chipping, and chipping volume. RESULTS: Regarding the effect of plane CBCT and CBCT + MAR on prepared crowns, a highly significant association between group I with group II (p = 0.001) and group III (p = 0.002) was detected. Regarding the cracking of SAH, significant differences between the zirconium crown and CFM restoration (p = 0.009) were found, while for the chipping, no significant association was seen between groups (p = 0.19). CONCLUSIONS: CBCT, either as a plane CBCT or with MAR, significantly improved the accuracy of drilling the screw channel and decreased injury to the existing restoration and abutment, aiding in better localization of SAH in loosened implant abutment screws.

Enhancing physicochemical, rheological properties, and in vitro rumen fermentation of starch with Melastoma candidum D. Don fruit extract.

The utilization of polyphenol-modified starch in ruminants has not undergone extensive exploration. This study aimed to investigate the impact of the complex formed between starch and Melastoma candidum D. Don fruit extract on physicochemical properties, phenol release kinetics in various buffers simulating the gastrointestinal tract, methane production, and post-rumen digestibility. The interaction between starch and M. candidum D. Don fruit extract significantly (p < 0.001) increased resistant starch and particle size diameter. The maximum phenolic release from complex between starch and M. candidum D. Don fruit extract, due to gastrointestinal tract-simulated buffers, ranged from 22.96 to 34.60 mg/100 mg tannic acid equivalent. However, rumen and abomasum-simulated buffers released more phenolic content, whereas the intestine-simulated buffer showed higher antioxidant activity (ferric ion-reducing antioxidant power). Furthermore, complex between starch and M. candidum D. Don fruit extract significantly decreased dry matter rumen digestibility (p < 0.001) and maximum methane gas production (p < 0.001).

Accuracy of the novel digital non-cross-arch surgical guides with integration of tooth undercut retention and screw-bone support for implant placement in mandibular free-end.

BACKGROUND: Large cross-arch free-end surgical guides can obscure the visual field, compromising surgical accuracy due to insufficient stability at the free-end. This in vitro study aims to evaluate the accuracy of novel digital non-cross-arch surgical guides designed for implant placement at the mandibular free-end, incorporating tooth undercut retention and screw-bone support. MATERIALS AND METHODS: A mandibular dental model lacking left molars was utilized to fabricate unilateral (cross-arch) tooth-supported surgical guides (GT I, n = 20). Subsequently, two additional types of surgical guides were fabricated: GT II (covering two teeth, n = 20) and GT III (covering three teeth, n = 20). These novel surgical guides were designed to utilize the undercut of the supporting teeth for retention and enhance stability with screw-bone support at the guide's free-end. Furthermore, 60 identical guiding blocks were assembled on the three types of surgical guides to facilitate the implants' insertion. On a phantom head, 120 implant replicas were placed at the Federal Dentaire Internationale (FDI) teeth positions #36 and #37 on the dental model, employing a combination of surgical guides and guiding blocks. To assess accuracy, planned and placed implant positions were compared using intraoral optical scanning. Discrepancies in angulation and linear deviations, including the coronal/apical 3D deviations, lateral deviation as well as depth deviation, were measured. Statistical analysis was performed using two-way ANOVA and Bonferroni test (α = 0.05). RESULTS: GT I exhibited significantly largest discrepancies, including angular and linear deviations at the crest and apex at every implant site. Especially in depth, at implant site #36, the mean deviation value of GT I (0.27 ± 0.13 mm) was twice as large as GT III (0.13 ± 0.07 mm), and almost twice as large as GT II (0.14 ± 0.08 mm). However, at implant site #37, this deviation increased to almost a five-fold relationship between GT I (0.63 ± 0.12 mm) and II (0.14 ± 0.09 mm), as well as between GT I and III (0.13 ± 0.09 mm). No significant discrepancies existed between the novel surgical guides at either implant site #36 or #37. CONCLUSION: This study provides a practical protocol for enhancing accuracy of implant placement and reducing the size of free-end surgical guides used at mandibular molar sites.

A 3D In-vitro model of the human dentine interface shows long-range osteoinduction from the dentine surface.

Emerging regenerative cell therapies for alveolar bone loss have begun to explore the use of cell laden hydrogels for minimally invasive surgery to treat small and spatially complex maxilla-oral defects. However, the oral cavity presents a unique and challenging environment for in vivo bone tissue engineering, exhibiting both hard and soft periodontal tissue as well as acting as key biocenosis for many distinct microbial communities that interact with both the external environment and internal body systems, which will impact on cell fate and subsequent treatment efficacy. Herein, we design and bioprint a facile 3D in vitro model of a human dentine interface to probe the effect of the dentine surface on human mesenchymal stem cells (hMSCs) encapsulated in a microporous hydrogel bioink. We demonstrate that the dentine substrate induces osteogenic differentiation of encapsulated hMSCs, and that both dentine and ß-tricalcium phosphate substrates stimulate extracellular matrix production and maturation at the gel-media interface, which is distal to the gel-substrate interface. Our findings demonstrate the potential for long-range effects on stem cells by mineralized surfaces during bone tissue engineering and provide a framework for the rapid development of 3D dentine-bone interface models.

Effect of rice bran fermented with Ligilactobacillus equi on in vitro fermentation profile and microbial population.

This study was conducted to assess the effects of fermented rice bran (FRB) with Ligilactobacillus equi on ruminal fermentation using an in vitro system. Oat hay, corn starch, and wheat bran were used as substrate for control. Ten percent of wheat bran was replaced with rice bran (RB), rice bran fermented with distilled water, and rice bran fermented with L. equi for T1, T2, and T3, respectively. The experimental diets were mixed with buffered rumen fluid from wethers under nitrogen gas and incubated for 24 h at 39°C. The fermentation profile and microbial population were analyzed after the incubations. The results revealed that the RB and FRB (with or without L. equi) significantly reduced the gas, methane (CH4), and CH4 per dry matter digested (p < 0.001). Total short-chain fatty acid was also reduced in T1 and T2 in comparison with the control (p < 0.001). Propionate proportion was increased while butyrate proportion was reduced in response to treatment addition in cultures (p < 0.001). Anaerobic fungi and Fibrobacter succinogenes abundance were decreased in treatments (p < 0.001). Overall, CH4 production in vitro can be reduced by RB and FRB supplementation as a result of the reduction of fiber-degrading microorganisms and a decrease in gas production.

In vitro evaluation of the potential of mites of the family Macrochelidae (Acari: Mesostigmata) as macrobiological agents against the nematode Haemonchus contortus (Strongylida: Trichostrongylidae).

Small ruminants (sheep and goats) constantly suffer from endoparasitoses caused by gastrointestinal nematodes. Among these, the species Haemonchus contortus (Rudolphi, 1803) is considered to be the one of greatest importance within sheep farming. This nematode is difficult to control due to its resistance to most commercial anthelmintics. The aim of the present study was to assess the potential of macrochelid mites as macrobiological agents for controlling endoparasitoses of sheep caused by the nematode, H. contortus. For this, novel in vitro methodology was used, in which assessments were made not only of the predatory ability but also the population growth of mite species (Macrocheles merdarius, Macrocheles robustulus and Holostaspella bifoliata) when offered larvae of the nematode, H. contortus. The predatory ability of the mites, M. merdarius and H. bifoliata were efficient regarding their predatory ability against H. contortus nematode larvae. The mite, M. merdarius exhibited the highest predation rate with mean distribution values for the treated group of 18656 ± 10091 and for the control group of 1178 ± 712 (P < 0.0001). The species, H. bifoliata presented the highest population growth rate, with a percentage acarid recovery rate of 263% in relation to the number added initially. The data from this in vitro predation experiment suggest that, M. merdarius and H. bifoliata showed promise as macrobiological agents for controlling gastrointestinal endoparasitoses of sheep caused by the nematode, H. contortus given that both species reduced the population of this helminth by more 70% and the number of mites recovered was three times greater than the number added.

An in vitro assessment of teething gels' effects on human gingival mesenchymal stem cells.

BACKGROUND: The aim of this study is to examine the cytotoxic effects of dental gels with different contents, which are frequently used during teething, on gingival mesenchymal stem cells (G-MSCs). METHOD: The teething gels used in this study were Dentinox, Gengigel, Osanite, and Jack and Jill. The human gingival mesenchimal stem cells (hG-MSCs) were incubated with these teething gel solutions (0.1%, 50% and 80% concentrations). Reproductive behavior of G-MSCs was monitored in real time for 72 h using the xCELLigence real-time cell analyzer (RTCA) system. Two-way repeated Anova test and post hoc Bonferroni test were used to evaluate the effect of concentration and dental gel on 0-hour and 72-hour viability. Significance was evaluated at p < 0.05 level. RESULTS: Teething gels prepared at 50% concentration are added to the G-MSC culture, the "cell index" value of G-MSCs to which Dentinox brand gel is added is significantly lower than all other groups (p = 0.05). There is a statistically significant difference between the concentrations in terms of cell index values at the 72nd hour compared to the 0th hour (p = 0.001). CONCLUSIONS: The local anesthetic dental gels used in children have a more negative effect on cell viability as concentration increases.

Dental restorative materials and halitosis: a preliminaryin-vitrostudy.

Despite the widespread use of dental restorative materials, little information exists in the literature regarding their potential impact on bad breath. This in vitro study aims to fill this gap by investigating the influence of different restorative materials on the release of hydrogen sulfide (H2S). Thirteen diverse dental restorative materials, including composites, flowable composites, glass ionomer restorative materials, high-copper amalgam, and CAD-CAM blocks, were examined. Cellulose Sponge models were used as negative and positive control. All samples were prepared with a diameter of 5 mm and a height of 2 mm. Except for the negative control group, all samples were embedded into Allium cepa L., and the emitted H2S was measured using the Wintact W8802 hydrogen sulfide monitor. Surface roughness's effect on emission was explored by roughening the surfaces of CAD-CAM material samples, and gas emission was measured again. The data were statistically analyzed using the Kruskal-Wallis test and DSCF pairwise comparison tests. Fiber-reinforced flowable composite (EverX Flow), amalgam (Nova 70-caps), and certain composite materials (IPS Empress Direct, Tetric Evoceram, Admira Fusion X-tra) released higher H2S concentrations compared to the negative control. The H2S release period lasted longer in the same materials mentioned above, along with G-aenial Universal Injectable. Indirectly used materials, such as GC Cerasmart, Vita Enamic, and Vita YZ HT, demonstrated significantly lower emissions compared to other direct restoratives. Importantly, the surface roughness of indirect materials did not significantly affect peak H2S concentrations or release times. The study reveals variations in H2S release among restorative materials, suggesting potential advantages of indirect restorative materials in reducing H2S-induced halitosis. This comprehensive understanding of the relationship between restorative materials and halitosis can empower both dental professionals and patients to make well-informed treatment choices. Notably, there is evidence supporting the enhanced performance of indirect restorative materials for individuals affected by halitosis.

The effect of freezing on the fracture pattern of adhesive on debonding: an in-vitro study.

The purpose of this study was to quantitatively evaluate adhesive remnants on the enamel surface following bracket debonding using a freezing element. Thirty-six sound premolars were used in this study. In each case, a bracket was bonded onto each tooth with conventional light-cured composite resin and de-bonded after one week. Freezing of the underlying composite through the bracket was performed immediately before debonding with a portable cryosurgical system (-55 °C). Specimens were divided into three groups according to the duration of freezing: a control group without freezing was used as a reference and two interventional groups with different durations of freezing (15 or 40 s). Brackets were removed by using debonding pliers to squeeze the wings of the bracket in an occluso-gingival manner. Adhesive remnants on the tooth were then quantitatively evaluated by stereo-microscopy. Pearson's Chi-squared test was used to investigate the relationship between the proportion of remaining resin and the group of teeth. In the control group, 100% of the composite remained on the enamel surface of all specimens. Significantly less adhesive remnants were found in the intervention groups (p = 0.001 for the 15 s group and p = 0.043 for the 40 s group). There was no significant difference between the two interventions (p = 0.165) in terms of the proportion of remaining adhesive remnants. Freezing of the bracket and the underlying adhesive resin prior to bracket debonding may favorably alter the behavioral pattern of composite fracture, thus reducing the extent of adhesive remnants on the enamel. Increasing the freezing time from 15 to 40 s did not exert significant effects on adhesive remnants following debonding. Further research now needs to investigate the effect of freezing on the mechanical properties of the adhesive remnants and its in-vivo effect on pulp vitality over both short- and long-terms.

Evaluation of various obturation techniques with bioceramic sealers in 3D-printed C-shaped canals.

This in vitro study compared various obturation techniques with bioceramic sealers for filling C-shaped 3D-printed replicas. A mandibular molar with a C-shaped root canal with a C1 configuration was obtained. After instrumenting with M3 Pro Gold files (United Dental, Shanghai, China) up to size #30/0.04, a CBCT scan of the tooth was taken. Sixty 3D-printed replicas of the tooth were created. The samples were obturated with EndoSeal TCS sealer (E. TCS; Maruchi, Wonju, Korea) or EndoSeal MTA (E. MTA; Maruchi, Wonju, Korea) (n = 30). The samples in each group were obturated with the following techniques (n = 10): (1) single-cone technique (SC), (2) SC with ultrasonic activation (UA), and (3) cold hydraulic compaction (CHC). Following incubation, the replicas' apical, middle, and coronal thirds were inspected under a digital microscope, and the proportion of filling material and void were calculated. Also, the obturation time and sealer extrusion were recorded. Data were analyzed using ANOVA, LSD post-hoc, and the chi-square tests (α = 0.05). The results indicated that in the apical third, E. TCS-SC, E. TCS-UA, and E. MTA-UA had the lowest void percentage among groups (p < 0.05). In the middle thirds, samples obturated with E. TCS-UA showed a significantly lower void percentage among all groups (p < 0.05). However, in the coronal third, E. TCS-CHC showed the least void percentage (p < 0.05), followed by E. TCS-UA and E. MTA-CHC. The E. TCS-SC and E. TCS-UA were the least time-consuming methods (p < 0.05). Sealer extrusion significantly differed among the groups, with E. MTA-UA and E. TCS-UA showing higher incidence (p = 0.019). It was concluded that E. TCS-UA was the most convenient obturation technique. However, care must be taken when obturating the canals with high flow and ultrasonic activation near the vital anatomical landmarks.

Effect of fence tray matching care on excess adhesive and bracket placement accuracy for orthodontic bonding: an in vitro study.

OBJECTIVE: This study aimed to evaluate the effect of fence tray matching care (FTMC) in bracket bonding by measuring excess adhesive, as well as linear and angular deviations, and by comparing it with the half-wrapped tray (HWT). MATERIALS AND METHODS: An intraoral scanner was used to acquire data on the maxillary dental arch of a patient with periodontitis.Furthermore, 20 maxillary dental arch models were 3D printed. Using 3Shape, PlastyCAD software, and 3D printing technology, 10 FTMC (method I) and HWT (method II) were obtained. By preoperative preparation, intraoperative coordination, and postoperative measurement, the brackets were transferred from the trays to the 3D-printed maxillary dental arch models. Additionally, the bracket's excess adhesive as well as linear and angular deviations were measured, and the differences between the two methods were analyzed. RESULTS: Excess adhesive was observed in both methods, with FTMC showing less adhesive (P< 0.001), with a statistical difference. Furthermore, HWT's vertical, tip and torque, which was significantly greater than FTMC (P< 0.05), with no statistical difference among other respects. The study data of incisors, canines, and premolars, showed that the premolars had more adhesive residue and were more likely to have linear and angular deviations. CONCLUSIONS: The FTMC had higher bracket bonding effect in comparison to HWT, and the adhesive residue, linear and angular deviations are smaller. The fence tray offers an intuitive view of the precise bonding of the bracket, and can remove excess adhesive to prevent white spot lesions via care, providing a different bonding method for clinical applications.

In-vitro biofilm removal from TiUnite® implant surface with an air polishing and two different plasma devices.

BACKGROUND: We investigated the efficacy of two different cold atmospheric pressure jet plasma devices (CAP09 and CAPmed) and an air polishing device with glycine powder (AP) either applied as monotherapies or combined therapies (AP + CAP09; AP + CAPmed), in microbial biofilm removal from discs with anodised titanium surface. METHODS: Discs covered with 7-day-old microbial biofilm were treated either with CAP09, CAPmed, AP, AP + CAP09 or AP + CAPmed and compared with negative and positive controls. Biofilm removal was assessed with flourescence and electron microscopy immediately after treatment and after 5 days of reincubation of the treated discs. RESULTS: Treatment with CAP09 or CAPmed did not lead to an effective biofilm removal, whereas treatment with AP detached the complete biofilm, which however regrew to baseline magnitude after 5 days of reincubation. Both combination therapies (AP + CAP09 and AP + CAPmed) achieved a complete biofilm removal immediately after cleaning. However, biofilm regrew after 5 days on 50% of the discs treated with the combination therapy. CONCLUSION: AP treatment alone can remove gross biofilm immediately from anodised titanium surfaces. However, it did not impede regrowth after 5 days, because microorganisms were probably hidden in holes and troughs, from which they could regrow, and which were inaccessible to AP. The combination of AP and plasma treatment probably removed or inactivated microorganisms also from these hard to access spots. These results were independent of the choice of plasma device.

Vascular Response of Triiodothyronine on Isolated Aortic Rings: Contribution of Redox Mechanisms. / Resposta Vascular da Triiodotironina sobre Anéis de Aortas Isoladas: Contribuição de Mecanismos Redox.

BACKGROUND: Vascular dysfunction constitutes the etiology of many diseases, such as myocardial infarction and hypertension, with the disruption of redox homeostasis playing a role in the imbalance of the vasomotor control mechanism. Our group previously has shown that thyroid hormones exert protective effects on the aortic tissue of infarcted rats by improving angiogenesis signaling. OBJECTIVE: Investigate the role of triiodothyronine (T3) on vascular response, exploring its effects on isolated aortas and whether there is an involvement of vascular redox mechanisms. METHODS: Isolated aortic rings (intact- and denuded-endothelium) precontracted with phenylephrine were incubated with T3 (10-8, 10-7, 10-6, 10-5, and 10-4 M), and tension was recorded using a force-displacement transducer coupled with an acquisition system. To assess the involvement of oxidative stress, aortic rings were preincubated with T3 and subsequently submitted to an in vitro reactive oxygen species (ROS) generation system. The level of significance adopted in the statistical analysis was 5%. RESULTS: T3 (10-4 M) promoted vasorelaxation of phenylephrine precontracted aortic rings in both intact- and denuded-endothelium conditions. Aortic rings preincubated in the presence of T3 (10-4 M) also showed decreased vasoconstriction elicited by phenylephrine (1 µM) in intact-endothelium preparations. Moreover, T3 (10-4 M) vasorelaxation effect persisted in aortic rings preincubated with NG-nitro-L-arginine methylester (L-NAME, 10 µM), a nonspecific NO synthase (NOS) inhibitor. Finally, T3 (10-4 M) exhibited, in vitro, an antioxidant role by reducing NADPH oxidase activity and increasing SOD activity in the aorta's homogenates. CONCLUSION: T3 exerts dependent- and independent-endothelium vasodilation effects, which may be related to its role in maintaining redox homeostasis.

FUNDAMENTO: A disfunção vascular constitui a etiologia de diversas doenças, incluindo infarto do miocárdio e hipertensão, diante da ruptura da homeostase oxi-redutiva ("redox"), desempenhando um papel no desequilíbrio do mecanismo de controle vasomotor. Nosso grupo demonstrou anteriormente que os hormônios tireoidianos melhoram a sinalização da angiogênese, exercendo efeitos protetores sobre o tecido aórtico de ratos infartados. OBJETIVOS: Investigar o papel da triiodotironina (T3) na resposta vascular, explorando seus efeitos em aortas isoladas e a presença de mecanismos redox vasculares. MÉTODOS: Anéis aórticos isolados (endotélio intacto e desnudado) pré-contraídos com fenilefrina foram incubados com T3 (10-8, 10-7, 10-6, 10-5 e 10-4 M) e a tensão foi registrada usando um transdutor de deslocamento de força acoplado a um sistema de coleta. Para avaliar o envolvimento do estresse oxidativo, os anéis aórticos foram pré-incubados com T3 e posteriormente submetidos a um sistema de geração de espécies reativas de oxigênio (ROS) in vitro. O nível de significância adotado na análise estatística foi de 5%. RESULTADOS: A T3 (10-4 M) promoveu o vasorrelaxamento dos anéis aórticos pré-contraídos com fenilefrina em endotélio intacto e desnudado. Os anéis aórticos pré-incubados na presença de T3 (10-4 M) também mostraram diminuição da vasoconstrição provocada pela fenilefrina (1 µM) em preparações de endotélio intacto. Além disso, o efeito vasorrelaxante da T3 (10-4 M) persistiu em anéis aórticos pré-incubados com éster metílico de NG-nitro-L-arginina (L-NAME, 10 µM), um inibidor inespecífico da NO sintase (NOS). Por fim, a T3 (10-4 M) exibiu, in vitro, um papel antioxidante ao reduzir a atividade da NADPH oxidase e aumentar a atividade da SOD nos homogenatos aórticos. CONCLUSÃO: A T3 exerce efeitos dependentes e independentes de endotélio, o que pode estar relacionado ao seu papel na manutenção da homeostase redox.

Mechanism of action of Coptidis Rhizome in treating periodontitis based on network pharmacology and in vitro validation.

OBJECTIVE: Explore the therapeutic mechanism of Coptidis Rhizome (CR) in periodontitis using network pharmacology, and validate it through molecular docking and in vitro experiments. METHODS: Screened potential active components and target genes of CR from TCMSP and Swiss databases. Identified periodontitis-related target genes using GeneCards. Found common target genes using Venny. Conducted GO and KEGG pathway analysis. Performed molecular docking and in vitro experiments using Berberine, the main active component of CR, on lymphocytes from healthy and periodontitis patients. Assessed effects on inflammatory factors using CCK-8, flow cytometry, and ELISA. RESULTS: Fourteen active components and 291 targets of CR were identified. 30 intersecting target genes with periodontitis were found. GO and KEGG analysis revealed oxidative stress response and IL-17 signaling pathway as key mechanisms. Molecular docking showed strong binding of Berberine with ALOX5, AKT1, NOS2, and TNF. In vitro experiments have demonstrated the ability of berberine to inhibit the expression of Th17 + and other immune related cells in LPS stimulated lymphocytes, and reduce the secretion of IL-6, IL-8, and IL-17. CONCLUSION: CR treats periodontitis through a multi-component, multi-target, and multi-pathway approach. Berberine, its key component, acts through the IL-17 signaling pathway to exert anti-inflammatory effects.

Effect of light-, chemical-, and dual-cured universal adhesives on the internal adaptation of resin composites to pulpal and gingival internal walls.

PURPOSE: To compare the internal adaptation of restorative systems bonded to mid-coronal and gingival dentin using light-cured, chemical-cured, and dual-cured adhesives, both immediately and after aging. METHODS: 60 molars were selected and received occluso-mesial preparations with dentin gingival margins. Restorations were performed using different restorative systems with light-cured, chemical-cured, and dual-cured adhesives. Internal adaptation was assessed by examining the percentage of continuous margin (%CM) at the pulpal and gingival dentin under a scanning electron microscope at x200 magnification. Half of the teeth were stored in sterile water for 24 hours, while the other half underwent 10,000 thermal cycles. Micro-morphological analysis was conducted on representative samples at x1,000 magnification. RESULTS: The restorative system with light-cured adhesive exhibited significantly lower %CM values at the gingival dentin, particularly after aging. Aging had a negative impact on the %CM values of the pulpal and gingival dentin in restorative systems with light-cured and dual-cured adhesives. Regional dentin variations influenced the %CM values, especially after aging, regardless of the restorative system used. The tested restorative system with chemical-cured adhesive is preferable for achieving improved internal adaptation when bonding to both mid-coronal and gingival dentin, compared to the other tested systems. CLINICAL SIGNIFICANCE: The study highlights the variations in adhesive performance between different regional dentin areas using the tested restorative systems.