Can vacuum-formed retainers maintain arch dimensions and alignment compared to Hawley and fixed bonded retainers after treatment with fixed appliances? A systematic review and meta-analysis.

BACKGROUND: Different types of retention appliances have been proposed over the years, but their effectiveness in maintaining arch dimensions and alignment after orthodontic treatment is still unclear. AIM: To assess the efficacy of vacuum-formed retainers (VFRs) in preserving arch widths, arch length, and anterior alignment in maxillary and mandibular arches, compared to removable Hawley retainers (HRs) or fixed bonded retainers (FBRs). Search methods: unrestricted literature search of five major databases up to March 2024. SELECTION CRITERIA: randomized/non-randomized clinical studies comparing VFRs to removable HRs or FBRs. DATA COLLECTION AND ANALYSIS: after duplicate study selection, data extraction, and risk of bias assessment, random effects meta-analyses of standardized mean differences and their 95% confidence intervals were performed, followed by meta-regressions, sensitivity analyses, and assessment of the quality of evidence with GRADE. RESULTS: Twenty-two prospective studies (4 non-randomized and 18 randomized controlled trials) involving 1797 patients (mean age 17.01 years, 38.3% males) were included. No significant differences were found in the intercanine width, intermolar width, and arch length between VFRs and HRs, in both arches (P > 0.05). However, VFRs were statistically more effective than HRs in terms of Little's irregularity scores (LII) in the maxilla (eight studies; SMD = -0.42; 95% CI: -1.03 to -0.09; P = 0.02; I2 = 73.4%) but not in the mandible (P = 0.12). No significant differences were reported for all considered outcomes between VFRs and FBRs in in both arches (P > 0.05), except for lower LII, where VFRs were significantly less efficient (eight studies; SMD = 1.49; 95% CI = 0.26-2.7; P = 0.02; I2 = 93%). Follow-up times, risk of bias, and wire type (of FBRs) did not show statistically significant effects on outcome variables. Sensitivity analyses showed robustness of the findings for including non-randomized and postretention studies. The certainty in these estimates was from moderate to low due to the risk of bias and inconsistency. CONCLUSIONS: Low to moderate quality evidence indicates that VFRs are as effective as HRs in maintaining arch widths, length, and alignment. Low-quality evidence found similar efficacy between VFRs and FBRs, with FBRs being statistically more effective at maintaining lower arch alignment, but the difference was not clinically significant. REGISTRATION: PROSPERO registration (CRD42024518433).

An assessment of knowledge, attitude, and practice regarding organ donation among students and physicians.

OBJECTIVE: To assess the knowledge, attitude and practice of students and physicians regarding tissue and organ donation at a teaching hospital. Methods: The cross-sectional study was conducted at the Dow University of Health Sciences, Karachi, in 2019, and comprised physicians and students of ether gender. Data was collected using a 43-item self-administered questionnaire. Dichotomous questions were scored as 1 or 0, while multiple-option questions were scored as 2, 1 or 0. Data was analysed using SPSS 25. RESULTS: Of the 859 subjects, 761(88.6%) were students with a mean age of 20.3±1.5 years and 98(11.4%) were physicians with a mean age of 30.6±9.4. Among the students, 630(82.8%) were medical students, while 131(17.2%) were dental. The largest group among the students was of those in the second year of their studies 271(35.6%). Besides, 531(69.8%) and 64(65.3%) physicians were females. Compared to males, female students reported better mean scores in terms of attitude, while higher practice scores were obtained by both male students and physicians (p=0.021). Muslim subjects scored comparatively lower in knowledge, attitude and practice terms than non-Muslims (p<0.05). CONCLUSIONS: There were high knowledge and attitude scores, while scores reflecting practice were low. Effective measures should be taken to encourage medical professionals to donate organs and promote organ donation.

Effect of Plant-Based Mouthwash (Morinda citrifolia and Ocimum sanctum) on TNF-α, IL-α, IL-ß, IL-2, and IL-6 in Gingival Crevicular Fluid and Plaque Scores of Patients Undergoing Fixed Orthodontic Treatment.

Background and Objectives: To investigate the antiplaque properties of two plant-based mouthwashes, Morinda citrifolia (MC) and Ocimum sanctum (OS), and their effect on TNF-α, IL-α, IL-ß, IL-2, and IL-6 in gingival crevicular fluid (GCF) of patients undergoing fixed orthodontic treatment. Materials and Methods: Seventy-five individuals were recruited according to defined inclusion and exclusion criteria. This study was structured into two distinct phases. Phase I was a combination of toothbrushing using toothpaste containing fluoride (Protocol A), while Phase II toothbrushing included fluoride toothpaste and use of a mouthwash (Protocol B). For Phase II, individuals participating in this study were allocated into different groups through a randomization process: Group 1-0.12% CHX, Group 2-5% MC, and Group 3-4% OS. Each individual's Phase I and Phase II scores were assessed. GCF was measured in three phases to determine the level of inflammatory biomarkers. The paired t-test evaluated the disparities between the pre- and post-plaque index. Categorical data were subjected to crosstab analysis to assess qualitative variables. The mean values of cytokine levels were presented. An unpaired t-test was employed to assess the levels of cytokines between individuals in Phase I and Phase II. Results: Toothbrushing, fluoride toothpaste, and the supplementary use of mouthwash (Phase II) resulted in mean plaque scores significantly lower than group A (p < 0.001). Cytokines TNF-α, IL-α, and IL-ß demonstrated a significant downward trend in herbal mouthwash users. Conclusions: In conjunction with fluoridated toothpaste and brushing, OS and MC can serve as a viable alternative to conventional synthetic mouthwash CHX. This combination demonstrates reducing mean plaque scores and diminishing the levels of cytokines TNF-α, IL-α, and IL-ß.

Levels of Inflammatory and Bone Metabolic Markers in the Gingival Crevicular Fluid of Individuals Undergoing Fixed Orthodontic Treatment in Comparison to Those Utilizing Invisalign.

Background and Objectives: Evaluation of the levels of cytokine and bone metabolic biomarkers (BMBs) in patients receiving fixed orthodontic therapy (FOT) and Invisalign. Materials and Methods: Sixty participants were enrolled after meeting the predefined inclusion criteria. Patients then underwent either FOT or Invisalign by allocating them randomly to each group (n = 30). The basic periodontal assessment was performed, including the plaque index (PI), gingival index (GI), and bleeding on probing (BoP), at baseline and again after 4 weeks. Gingival crevicular fluid (GCF) samples were taken from each individual at baseline and after 4 weeks. An enzyme-linked immunosorbent assay (ELISA) technique was used to determine the cytokine and BMB levels. An unpaired t-test compared the FOT and Invisalign group's means and SDs. Paired t-tests examined the difference between T0 baseline and T1. Results: Patients treated with either FOT or Invisalign presented no statistically significant difference in terms of periodontal parameters such as PI, GI, and BoP (p > 0.05). The levels of IL-6 were significantly higher in patients treated with FOT as compared to Invisalign at T1 (p < 0.05) The other tested cytokines, IL-10, 13, 17, and GM-CSF, were not significantly different in either the FOT or Invisalign group at baseline and 4 weeks follow-up (p > 0.05). Regarding BMBs, it was detected that NTx and OC levels in both of the investigated groups were not significantly different at baseline and after 4 weeks (p > 0.05). However, NTx levels rose significantly (p < 0.05) and OC levels fell from T0 to T1. Conclusions: FOT and Invisalign displayed comparable outcomes in terms of cytokine and BMB levels. However, only IL-6 and NTx were significantly different at week 4 from baseline.

Evaluation of skeletal variations and establishment of Cephalometric Norms in Saudi Sub Population using Bjork Jarabak's analysis.

OBJECTIVE: To evaluate the skeletal variations amongst individuals and to compare the measurements with the standardized linear and angular values of Bjork Jarabak's analysis. METHODS: This study was conducted at POS Department, King Khalid University on 100 adult Saudi patients recruited through convenience sampling. It was conducted between April to September 2017, had inclusion criteria of patients between the age group 17 to 22 years showing normal occlusion. After history and examinations, lateral cephalographs were taken, scanned and traced using Dolphin Imaging Software and Cephalometric points were recognized. Linear and angular dimensions were calculated according to Bjork-Jarabak's method. RESULTS: Analysis and assessment of Saudi male and female values revealed considerable variation in the anterior and posterior cranial base lengths (p<0.05), anterior and posterior face height, ramus height, and mandibular length. Male measurements in contrast to Jarabak's values showed noteworthy variances in articular angle, anterior and posterior cranial base, ramus height, length of mandible, anterior face height and Jarabak's ratio. Female dimensions in relation to Jarabak's norms showed considerable variances in articular angle, anterior cranial base, posterior facial height with less significant values in Saudi females while compared with Jarabak's norms apart from mandibular body length which is more in Saudi females. CONCLUSION: Skeletal variations amongst Saudi males and females were significant and comparison with standardized linear and angular values of Bjork Jarabak's analysis was also significant.

Single-step synthesis of monolithic comb-like CdS nanostructures with tunable waveguide properties.

Using a simple in situ seeding chemical vapor deposition (CVD) process, comb-like (branched) monolithic CdS micro/nanostructures were grown. Efficient optical coupling between the backbone and the teeth of the branched architecture is demonstrated by distributing light from an UV-laser-excited spot at one end of the backbone to all branch tips. By varying the deposition conditions, the orientation of the branches with respect to the backbone, their size and density can be tuned as well as the size of the backbone. This in situ seeding CVD method has the potential for a low-cost single-step fabrication of high-quality, micro/nanointegrated photonic devices, with tunable complex waveguiding possibilities.

Salivary and crevicular fluid proinflammatory cytokines and advanced glycation end products in patients with different glycemic levels undergoing fixed orthodontic treatment.

OBJECTIVE: To examine whether patients with different blood glycemic levels undergoing fixed orthodontic therapy demonstrate changes in the biochemical profiles of crevicular fluid and salivary advanced glycation end products (AGEs) and proinflammatory cytokine levels in comparison with nondiabetic healthy subjects. MATERIALS AND METHODS: Prediabetic subjects, subjects with type 2 diabetes mellitus (T2DM), and subjects without a diabetes mellitus diagnosis undergoing fixed orthodontic therapy with MBT prescription brackets (0.022-inch brackets and 0.019 × 0.025-inch stainless steel archwires) were included in the study. The following clinical periodontal parameters were evaluated: (1) plaque score (PS), (2) probing depth (PD), (3) bleeding on probing (BOP), and (4) clinical attachment loss. Crevicular fluid and saliva specimens were collected during regular orthodontic visits. Salivary and crevicular fluid tumor necrosis factor alpha, interleukin-6, ghrelin, resistin, AGEs, and receptor activator of nuclear factor κΒ ligand were evaluated using a human magnetic Luminex multiplex assay. RESULTS: BOP scores were significantly higher among T2DM subjects (19.2%) than among nondiabetic subjects (11.2%) and prediabetic subjects (15.9%). Comparable values were demonstrated by all three study groups regarding PD scores and PSs. T2DM subjects demonstrated higher scores for gingival crevicular fluid (GCF) chemokines than nondiabetic and prediabetic subjects. A statistically significant difference was found in the levels of AGEs and resistin among the three study groups. The scores revealed for the levels of GCF resistin and AGEs versus periodontal BOP demonstrated a significant positive association by the Pearson correlation test. CONCLUSIONS: T2DM patients demonstrated significantly higher levels of GCF resistin and AGEs during fixed orthodontic therapy. Chronic hyperglycemic patients undergoing orthodontic therapy demonstrated a proinflammatory response.

Orthodontic adhesive loaded with different proportions of ZrO2 silver-doped nanoparticles: An in vitro µTBS, SEM, EDX, FTIR, and antimicrobial analysis.

Zirconium dioxide silver-doped nanoparticles (ZrO2AgDNPs) impacts the adhesive material in terms of its physical characteristics, antimicrobial properties, degree of conversion (DC), and micro-tensile bond strength (µTBS) of orthodontic brackets to the enamel surface. A comprehensive methodological analysis utilizing a range of analytical techniques, including scanning electron microscopy coupled with energy-dispersive x-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, DC analysis, and µTBS testing. A light-curable orthodontic adhesive, specifically Transbond XT, was combined with ZrO2AgDNPs at 2.5% and 5%. As a control, an adhesive with no incorporation of ZrO2AgDNPs was also prepared. The tooth samples were divided into three groups based on the weightage of NPs: group 1: 0% ZrO2AgDNPs (control), group 2: 2.5 wt% ZrO2AgDNPs, and group 3: 5 wt% ZrO2AgDNPs. EDX graph demonstrated silver (Ag), Zirconium (Zr), and Oxygen (O2), The antibacterial efficacy of adhesives with different concentrations of NPs (0%, 2.5%, and 5%) was assessed using the pour plate method. The FTIR spectra were analyzed to identify peaks at 1607 cm-1 corresponding to aromatic CC bonds and the peaks at 1638 cm-1 indicating the presence of aliphatic CC bonds. The µTBS was assessed using universal testing machine (UTM) and bond failure of orthodontic brackets was seen using adhesive remanent index (ARI) analysis. Kruskal-Wallis test assessed the disparities in survival rates of Streptococcus mutans. Analysis of variance (ANOVA) and post hoc Tukey multiple comparisons test calculated µTBS values. The lowest µTBS was observed in group 1 adhesive loaded with 0% ZrO2AgDNPs (21.25 ± 1.22 MPa). Whereas, the highest µTBS was found in group 3 (26.19 ± 1.07 MPa) adhesive loaded with 5% ZrO2AgDNPs. ZrO2AgDNPs in orthodontic adhesive improved µTBS and has acceptable antibacterial activity against S mutans. ZrO2AgDNPs at 5% by weight can be used in orthodontic adhesive alternative to the conventional method of orthodontic adhesive for bracket bonding. RESEARCH HIGHLIGHTS: The highest µTBS was found in orthodontic adhesive loaded with 5% ZrO2AgDNPs. ARI analysis indicates that the majority of the failures fell between 0 and 1 among all investigated groups. The colony-forming unit count of S. mutans was significantly less in orthodontic adhesive loaded with nanoparticles compared with control. The 0% ZrO2AgDNPs adhesive showed the highest DC.

Visible light-activated curcumin-doped zinc oxide nanoparticles integrated into orthodontic adhesive on Micro-tensile bond strength, degree of conversion, and antibacterial effectiveness against Staphylococcus Aureus. An investigation using scanning electron microscopy and energy-dispersive X-ray spectroscopy.

AIM: To acquire a thorough comprehension of the photoactivated Cur-doped ZnONPs at different concentrations 0%, 2.5%, and 5% on the physical qualities, antibacterial efficacy, degree of conversion, and µshear bond strength between orthodontic brackets and the enamel surface. MATERIAL AND METHODS: An extensive investigation was carried out utilizing a range of analytical methods, scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, micro tensile bond strength (µTBS) testing, and evaluation of antibacterial effectiveness. Cur-doped ZnONPs at concentrations of 2.5% and 5% were blended with Transbond XT, a light-curable orthodontic adhesive. A control group without the addition of Cur-doped ZnONPs was also prepared. The tooth samples were categorized into three groups based on the weight percentage of NPs: Group 1 (control) with 0% Cur-doped ZnONPs, Group 2 with 2.5 wt% Cur-doped ZnONPs, and Group 3 with 5 wt% Cur-doped ZnONPs. The SEM technique was employed to analyze the morphological characteristics of Cur-doped ZnONPs and ZnONPs. The composition and elemental distribution of the modified Cur-doped ZnONPs were assessed using energy-dispersive X-ray spectroscopy. The effectiveness of NPs at various concentrations against S.Mutans was gauged through the pour plate method. DC of Cur-doped ZnONPs at a region of 1608 cm-1 to 1636 cm-1 for the cured area, whereas the uncured area spanned the same range of 1608 cm-1 to 1636 cm-1 was assessed. The Adhesive Remnant Index (ARI) approach was utilized to investigate the bond failure of orthodontic brackets, while a Universal Testing Machine (UTM) was utilized to test µTBS. The Kruskal-Wallis test was employed to investigate variations in S.mutans survival rates. To determine the µTBS values, analysis of variance (ANOVA) and the post hoc Tukey multiple comparisons test were used. RESULTS: The maximum µTBS was given and documented in group 3: 5 wt% Cur-doped ZnONPs (21.21 ± 1.53 MPa). The lowest µTBS was given in group 2: 2.5 wt% Cur-doped ZnONPs (19.58 ± 1.27 MPa). The highest efficacy against S.mutans was documented in group 3 in which 5 wt% Cur-doped ZnONPs (0.39 ± 0.15). The lowest efficacy was seen in group 1 in which no Cur-doped ZnONPs were used (6.47 ± 1.23). The ARI analysis indicated that the predominant failure was between scores 0 and 1 among all experimental groups. Control group 1 which was not modified showed the highest DC (73.11 ± 4.19). CONCLUSION: Orthodontic adhesive, containing 5% Cur-doped ZnONPs photoactivated with visible light exhibited a favorable impact on µTBS and indicated enhanced antibacterial efficacy against S.mutans. Nevertheless, it was observed that the addition of Cur-doped ZnONPs at different concentrations (2.5%,5%) resulted in a decrease in the monomer-to-polymer ratio compromising DC.

Photoactivated riboflavin-doped hydroxy apatite nanospheres infiltered in orthodontic adhesives.

To assess micro-tensile bond strength (µTBS), degree of conversion (DC), microleakage (ML) antibacterial efficacy, and adhesive remnant index (ARI) of orthodontic brackets to enamel with different concentrations of photoactivated riboflavin-doped hydroxyapatite (HA) nanospheres (NS) (0%,1%,5% and 10%) and 0.5 wt% RF alone in orthodontic adhesive. Samples were included on the predefined inclusion criteria and positioned up to the cementoenamel junction (CEJ). Hydroxy apatite nanospheres (HANS) commercially bought were doped with RF. Surface characterization of HANS and RF-doped HANS were assessed along with EDX analysis. Samples were grouped based on experimental orthodontic adhesive modification. Group 1: Transbond XT no modification, Group 2: experimental Transbond XT 0.5 wt% RF, Group 3: experimental Transbond XT 0.5 wt% RF-doped 1% HANS, Group 4: experimental Transbond XT 0.5 wt % RF-doped 5% HANS and Group 5: Experimental Transbond XT 0.5 wt% RF-doped 10% HANS. Brackets were placed based on different adhesive modifications and samples underwent thermocycling. Samples were evaluated for µTBS, DC, and ML. The type of failure was assessed using ARI. Adhesive modified and un-modified in four different concentrations (0%, 1%, 5%, and 10%) and 0.5 wt% RF only were used to test efficacy against Streptococcus mutans (S.mutans). The survival rate of S.mutans and ML was determined using the Kruskal-Wallis Test. For the analysis of µTBS, ANOVA was employed, followed by a post-hoc Tukey HSD multiple comparisons test. The highest µTBS and lowest ML were observed in Group 2 experimental Transbond XT 0.5 wt% RF only. The lowest µTBS, highest ML, and lowest DC was seen in Group 5 experimental Transbond XT 0.5 wt% RF-doped 10% HANS. Samples in Group 1 in which Transbond XT was used as adhesive demonstrated significantly the highest microbial count of S.mutans and DC. Photoactivated RF-doped HANS in 1% and 0.5 wt% Riboflavin alone in orthodontic adhesive for metallic bracket bonding improved micro tensile bond strength, ML, DC, and antibacterial scores. RESEARCH HIGHLIGHTS: The highest µTBS and lowest ML were observed in Group 2 experimental Transbond XT 0.5 wt% RF only. The lowest µTBS, highest ML, and lowest DC was seen in Group 5 experimental Transbond XT 0.5 wt% RF-doped 10% HA-NS. Samples in Group 1 in which Transbond XT was used as adhesive demonstrated significantly the highest microbial count of S.mutans and DC.

Assessment of changes in enamel colour following fixed orthodontic therapy using an advanced spectrophotometer: An in vivo study.

BACKGROUND: Any manipulation of the surface of natural teeth may result in a variation of their colour. The fixed orthodontic treatment (FOT) is one such procedure which alters the enamel surface during the procedure. OBJECTIVE: To clinically evaluate the colour changes in teeth associated with comprehensive FOT (to compare the changes in test and control groups) and to determine the relationship of age and gender on enamel colour due to FOT by using an advanced spectrophotometer. METHODS: The selection of sixty patients for the study was done randomly and among these thirty patients who underwent the FOT as the case group, the other thirty patients who did not need FOT, were the control group. The recordings of spectrophotometric data were done in a standardized manner for all patients in the labial circular region of every anterior tooth, following debonding and cleaning operations, and before bracket bonding. The Commission Internationale de l'Eclairage's L*, a*, and b* (lightness, red/green, and blue/yellow) tooth-type characteristics were used to measure color, and the associated color differences (DE) between the groups were computed. One-way ANOVA (a < 0.05) and the paired t-test were used to evaluate any changes in these color characteristics. RESULTS: Fixed orthodontic treatment is associated with changes in colour parameters. L* values decreased (P< 0.001), while a* and b* values increased (P< 0.001) at the end of treatment. All measured tooth types showed significant colour change (DE); their mean differences ranged from 1.64 to 2.96 DE units. CONCLUSIONS: Fixed orthodontics can change the natural colour of teeth. The CIE colour parameters L*, a*, and b* of natural teeth showed statistically significant differences after debonding the orthodontic appliances. The L* values decreased making the teeth look darker. The adolescent and male patients had more tooth colour changes than the adult and female groups.

Effect of adding sodium fluoride and nano-hydroxyapatite nanoparticles to the universal adhesive on bond strength and microleakage on caries-affected primary molars.

Evaluation of micro tensile bond strength (µTBS) and marginal leakage of sodium fluoride (NaF) and nano-hydroxyapatite (n-HA) modified universal adhesives (UAs) bonded using etch-and-rinse (ER) and self-etch (SE) bonding technique to the carious affected dentin (CAD). One hundred and twenty primary molars were prepared for CAD on the occlusal surface. The occlusal CAD surface was flattened and underwent a polishing procedure. The specimens were divided into six groups using a random allocation method based on the UAs applied and the mode of etching used (n = 20) Group A1: UAs (ER), Group B1: UAs (SE), Group A2: UAs (NaF) + ER, Group B2: UAs (NaF) + SE, Group A3: UA (n-HA) + ER and Group B3: UAs (n-HA) + SE. Composite restoration was placed and samples were thermocycled. Microleakage, µTBS, and failure mode assessment were performed using a dye penetration test, universal testing equipment, and stereomicroscope respectively. The µTBS and microleakage results (mean ± SD) were examined using analysis of the variance (ANOVA) and Tukey post hoc tests. Group B1 (UAs + SE) demonstrated the maximum scores of microleakage (25.14 ± 9.12 nm) and minimum recorded value of µTBS (14.16 ± 0.55 MPa). In contrast, Group A3 (UAs (n-HA) + ER) displayed a minimum value of marginal leakage (12.32 ± 6.33 nm) and maximum µTBS scores (19.22 ± 0.92 MPa). The outcomes of the intergroup comparison analysis showed that Group A2 (UAs (NaF) + ER), Group B2 (UAs (NaF) + SE), Group A3 (UA (n-HA) + ER) and Group B3 (UAs (n-HA) + SE) presented comparable outcomes of marginal seal outcomes and µTBS scores (p > 0.05). NaF and n-HA-modified UAs displayed favorable bond strength and minimum marginal leakage to the deciduous affected dentin surface.

Modified Hybrid Hydroxyapatite-Silver Nanoparticles Activated via a Blue Light Source in Various Concentrations in Two-Step Self-Etch Adhesive to Caries-Affected Primary Dentin.

Aims: To evaluate hydroxyapatite-silver (HA-Ag) hybrid nanoparticles (NPs), as an antibacterial agent when integrated in self-etch (SE) adhesive. Blue light activated HA-Ag hybrid NP incorporation on mechanical properties, degree of conversion (DC), and microtensile bond strength (µTBS). Method: Eighty primary molar teeth have carious lesions reaching the dentin but not involving the pulp. The infected dentin was removed and carious-affected dentin (CAD) was preserved. Forty samples were inoculated with Streptococcus mutans. All primary teeth (n = 80) were allocated into four groups based on the incorporation of HA-Ag hybrid NPs in different concentrations (0%, 1%, 5%, and 10%). Group 1: 0% HA-Ag hybrid NPs + Clearfil SE bond primer, group 2: 1% HA-Ag hybrid NPs + Clearfil SE bond primer, group 3: 5 wt% HA-Ag NPs + Clearfil SE bond primer, and group 4: 10 wt% HA-Ag NPs + Clearfil SE bond primer. The survival rate assessment of S. mutans was conducted on 40 inoculated samples. On the remaining primary teeth (n = 40), Clearfil SE bonding agent was applied uniformly via a blue light source. The composite buildup was performed on the samples and µTBS and failure analysis assessed. Fourier transform infrared spectroscopy was performed to assess DC. Survival rates of S. mutans and µTBS among the tested groups were compared using ANOVA and Tukey post hoc analysis. Results: 10 wt % HA-Ag NPs + Clearfil SE bond primer exhibited the highest level of antibacterial efficacy (0.14 ± 0.02 CFU/mL) against S. mutans. The highest µTBS (18.38 ± 0.78 MPa) at the composite/CAD interface was in group 2 (1 wt % HA-Ag NPs + Clearfil SE bond primer + Clearfil SE bonding agent + activation with a blue light source). The highest DC was observed in the control group with Clearfil SE bond primer + Clearfil SE bonding agent + activation with a blue light source. Conclusion: 1 wt% HA-Ag hybrid NPs showed enhanced antibacterial effectiveness, DC, and bond strength of the SE adhesive to the primary CAD.

Role of six cytokines and bone metabolism biomarkers in gingival crevicular fluid in patients undergoing fixed orthodontic appliance treatment in comparison with aligners: a clinical study.

OBJECTIVES: The objective of this study was to assess bone biomarkers and cytokines in patients with conventional labial appliances (CLAs) and aligners. MATERIALS AND METHODS: Participants were recruited to undergo orthodontic treatment with CLAs and aligners according to predefined inclusion and exclusion criteria. Periodontal examination was accomplished at baseline and 4 weeks using the plaque index (PI), gingival index (GI), and bleeding on probing (BoP). Samples of gingival crevicular fluid (GCF) were collected at baseline (T0) before the start of treatment and at the 1-month follow-up (T1) to assess bone metabolic and inflammatory biomarkers. GCF from participants with CLAs and aligners was evaluated with enzyme-linked immunosorbent assay. Comparison between labial conventional orthodontic treatment and aligners were assessed using an unpaired t-test. The difference between T0 and T1 was measured using a paired t-test. RESULTS: BoP, PI, and GI demonstrated no significant difference between participants treated with aligners and subjects with CLAs at baseline and at 4 weeks (P > .05). Bone markers and other biomarkers (tumor necrosis factor α, interleukin [IL]-α, IL-2, IL-6, and IL-8) showed significant differences (P < .05). Also, a significant difference between CLAs and aligners was noted among all biomarkers (P < .05) except IL-ß. CONCLUSIONS: Aligners and CLAs increase the level of inflammatory and bone metabolic biomarkers after 1 month.

Novel use of chloro-aluminum phthalocyanine assisted photodynamic therapy helps in periimplant healing among smoking patients.

AIMS: To evaluate the clinical and biochemical peri­implant parameters using chloro­aluminum phthalocyanine-(CAP) mediated antimicrobial photodynamic therapy (PDT) as an adjunct to non-surgical mechanical debridement (NSD) in cigarette smokers (CS) and never-smokers (NS) with peri­implantitis. MATERIALS AND METHODS: Thirty-two patients with peri­implantitis [Group CS - 16 and Group NS - 16] were recruited for the trial. The study participants underwent two therapies: PDT + NSD and NSD alone. The clinical peri­implant parameters assessed in this clinical trial were bleeding on probing (BP), crestal bone loss (CBL) peri­implant pocket depth (PD), and peri­implant plaque scores (PS), respectively. Peri-implant crevicular fluid was sampled and the quantification of interleukin (IL)-1ß and tumor necrosis factor-alpha (TNF-α) was performed using enzyme linked immunosorbent assay (ELISA). RESULTS: BP was significantly reduced at 6 months after PDT+NSD in CS groups. Mean PD significantly reduced after both PDT+NSD and NSD subgroups within both NS and CS groups. Only at 6 months did PDT+NSD showed statistically significantly reduced IL-1ß levels in the NS group. TNF-α levels significantly reduced in CS group with PDT+NSD and NSD alone at both 3 months and 6 months follow up. CONCLUSION: CAP-assisted PDT helped to improve the clinical and cytokine levels after non-surgical peri­implant mechanical debridement in treating peri­implantitis patients in smokers.

Caries-affected dentin disinfection using Triphala, Indocyanine green, and Potassium Titanyl Phosphate laser and their effect on adhesive bond strength.

AIM: To assess the impact of new cavity sterilization types using ozone water (OW), Potassium Titanyl Phosphate laser (KTPL), Triphala, and indocyanine green photosensitizer (ICGP) on adhesive bond strength. MATERIALS AND METHODS: Fifty human permanent molars were included based on the criteria of International Caries Detection and Assessment System (ICDAS) scores 4 and 5 visual examinations, surface hardness valuation, staining by a caries detector solution, and radiographs. Caries-affected dentin (CAD) samples were randomly distributed into groups based on methods of disinfection (n = 10). Group 1: chlorhexidine, group 2: ow, group 3: KTPL, group 4: Triphala, and group 5: ICGP. Following disinfection, specimens were applied with Adper prime and bond NT and then restored with resin composite. All specimens were positioned in a jig of the universal testing machine for shear bond strength (SBS). The debonded samples were analyzed under a stereomicroscope at 40x magnification to determine the type of failure. Analysis of variance (ANOVA) and Tukey HSD tests were used keeping the level of significance p < 0.05. RESULTS: The highest bond of adhesive resin was displayed by group 2 specimens cleaned using OW (16.71 ± 0.19 MPa). Whereas, the lowest bond integrity was observed by group 5 specimens disinfected using ICGP (11.21 ± 0.16 MPa). It was observed samples disinfected with OW (16.71 ± 0.19 MPa) in group 2 and samples in group 4 (16.09 ± 0.26 MPa) treated with Triphala displayed comparable outcomes of bond strength (p > 0.05). It was observed that group 2 (70%) and 4 (80%) treated specimens accounted mostly for cohesive failure. However, groups 1 (80%), 3 (60%), and 5 (70%) displayed an adhesive failure pattern. CONCLUSION: OW and Triphala displayed better bond integrity of adhesive resin to CAD and therefore have the potential to be used as a cavity disinfectant in clinical settings. However, ICGP and KTPL displayed weak bonds of adhesive to CAD. More work is needed to extrapolate the findings of the present study.

Effect of two hemostatic agents containing Aluminium chloride and ferric sulfate on bond integrity of resin-modified glass ionomer cement.

OBJECTIVE: To evaluate the influence of hemostatic agents (Expasyl and Viscostat) on the bond values of RMGIC bonded to pretreated dentin surface with cavity conditioner (CC), self etch primer (SEP), and antimicrobial photodynamic therapy (aPDT) MATERIALS AND METHODS: One hundred and eighty human third molars were embedded in a self-cure acrylic resin-filled polyvinyl cylinder. The dentinal surface was prepared and all the samples were arbitrarily distributed into three different groups liable to the hemostatic agent used (n = 60). Samples in group 1: no hemostatic agent used, Group 2: Samples exposed to Expasyl, and group 3: Viscostat. After applying the hemostatic agent, all the samples were surface treated with different surface conditioners. Subgroup A1, B1, C1 were conditioned with aPDT, Subgroup A2, B2, and C2 surface were treated with SEP, and Subgroup A3, B3, and C3 were smeared with CC. RMGIC was placed and SBS was assessed using a universal testing machine and failure mode analysis was performed using and stereomicroscope at 40x magnification. Analysis of variance (ANOVA) and Tukey's post hoc test compared the means and standard deviations (SD) following SBS testing (p = 0.05). RESULTS: Highest SBS was exhibited by group A2 (22.36 ± 1.66 MPa Control - SEP) whereas group A1 (14.14 ± 1.32 aPDT + Control) demonstrated the lowest SBS. Subgroups B1 (17.23 ± 0.33- Expasyl + aPDT) and C1 (18.36 ± 0.25 MPa -Viscostat + aPDT) were found to be comparable (p > 0.05). Similarly, A3 (19.69 ± 1.01- Control + CC) and B3 (18.23 ± 0.33 MPa- Expasyl + CC) and C3 (18.36 ± 0.37 Viscostat + CC) demonstrated no significant difference in bond scores (p > 0.05). Most of the failures in aPDT were adhesive. However, SEP and CC groups demonstrated admixed and cohesive failure CONCLUSION: Dentin conditioned by aPDT after hemostatic agents improves bond values of RMGIC. Self etch Primer and Cavity conditioner using polyacrylic acid without hemostatic agent improves bond integrity of RMGIC.

Versatile Chemical Recycling Strategies: Value-Added Chemicals from Polyester and Polycarbonate Waste.

ZnII -complexes bearing half-salan ligands were exploited in the mild and selective chemical upcycling of various commercial polyesters and polycarbonates. Remarkably, we report the first example of discrete metal-mediated poly(bisphenol A carbonate) (BPA-PC) methanolysis being appreciably active at room temperature. Indeed, Zn(2)2 and Zn(2)Et achieved complete BPA-PC consumption within 12-18 mins in 2-Me-THF, noting high bisphenol A (BPA) yields (SBPA =85-91 %) within 2-4 h. Further kinetic analysis found such catalysts to possess kapp values of 0.28±0.040 and 0.47±0.049 min-1 respectively at 4 wt%, the highest reported to date. A completely circular upcycling approach to plastic waste was demonstrated through the production of several renewable poly(ester-amide)s (PEAs), based on a terephthalamide monomer derived from bottle-grade poly(ethylene terephthalate) (PET), which exhibited excellent thermal properties.

Ultrastructural and physicochemical characterization of pH receptive chlorhexidine-loaded poly-L-glycolic acid-modified orthodontic adhesive.

This study aims to evaluate the feasibility of chlorhexidine (CHX)-loaded poly-L-glycolic acid (PLGA) nanoparticles as a modifier of a commercial orthodontic adhesive via the assessment of physicochemical, biological, and mechanical properties at tooth-bracket interface. CHX-loaded PLGA nanoparticles were synthesized using double emulsion-solvent evaporation method and characterized using transmission electron microscopy and Raman analysis. CHX-loaded PLGA nanoparticles in Transbond XT orthodontic adhesive were prepared using two different concentrations of the CHX (25 and 50%) and characterized for degree of conversion (DC), antimicrobial, and cytotoxicity testing. Bonded specimens were tested for shear bond strength (SBS) and adhesive remnant index (ARI) at tooth-bracket interface. The synthesized PLGA nanoparticles averaged between 60 and 80 nm in size. After loading CHX inside PLGA nanoparticles, the morphology of the PLGA nanoparticles was considerably changed. Orthodontic bracket bonded with 25% CHX-loaded PLGA-modified adhesive demonstrated DC scores similar to control group. Both 25 and 50% CHX-loaded PLGA-modified adhesive specimens showed higher antibacterial activity against S. mutans compared to control group. The least mean SBS values were exhibited by 50% CHX-loaded PLGA-modified adhesive samples, while a statistically significant difference was observed in the mean ARI values among all study groups at all-time points (p = .018). This study indicates that the addition of CHX-loaded PLGA nanoparticles in Transbond XT achieved stable bonds with enhanced antimicrobial and mechanical properties.

Disinfection of caries-affected dentin using potassium titanyl phosphate laser, Rose bengal and Ozonated water on shear bond strength of deciduous teeth.

AIM: To assess the efficacy of disinfection of caries-effected dentin (CAD) using KTP laser and different decontamination methods using ozonated water (OW), Rose Bengal photosensitizer (RBP), chlorhexidine (CHX), and Er, YAG laser on the shear bond strength (SBS) of adhesive resin bonded to deciduous teeth. MATERIAL AND METHODS: A total of 50 extracted and radiographically verified carious primary molars were collected and scrutinized according to ICDAS criteria. Specimens were allocated randomly into five groups (n = 10) as per the type of CAD disinfectants. KTP laser, OW, RBP, CHX (control), and Er, YAG laser. After cavity sanitization, a resin adhesive (prime and bond NT) was smeared on the dentinal exterior followed by incremental composite filling. SBS evaluation was performed by employing specimens in the universal testing machine. The debonded surface was assessed under 40x magnification in a stereomicroscope to ascertain fracture mode. Statistical analysis was done by using the ANOVA and the Post Hoc Tukey multiple comparison tests (p < 0.05). RESULTS: The highest SBS was exhibited by group 2 i.e., when OW was employed for CAD disinfection (10.25 ± 0.24 MPa). Whereas, the lowest SBS bond value was unveiled by samples in group 3 when RBP was applied for dentin surface sanitization (7.85 ± 0.59 MPa).CAD disinfection with KTP laser (8.25 ± 0.41 MPa), CHX (8.19 ± 0.73 MPa), and RBP displayed comparable bond values (p > 0.05). CONCLUSION: Ozonated water and Er, YAG laser could be employed as cavity disinfectants in primary teeth as they demonstrated better shear bond strength without jeopardizing the adhesive binding capacity of restorative resins bonded to caries-affected dentin.