Aim: To compare the effect of different ultraviolet-C (UV-C) light exposure times on the dimensional stability of addition silicone dental impressions. Materials and methods: The dimensional stability of the addition silicone dental impressions was assessed by measuring specific dimensions on dental casts that were recovered from an upper acrylic resin model of dental implants. The impressions were reproduced using a customized tray adapted in a three-point simplex dental articulator permitting only opening and closing movements. Addition silicone dental impressions were divided into five groups (N = 12) according to the UV-C light exposure time. Group A was untreated; group B received 10 minutes; group C, 20 minutes; group D, 30 minutes; and group E, 40 minutes. All the impressions were poured with type IV dental stone and the internal edges of the upper silicone retainers of impression copings were used as five reference points (E, D, C, B, and A) to determine six linear measurements between ED, CB, EA, AD, EB, and CD points using a traveling microscope of 0.001 mm accuracy. One-way analysis of variance (ANOVA) was used for the statistical analysis (p < 0.05). Results: Expansion and contraction were noted among ED, CB, EA, and EB measurements, whereas only expansion was noted among AD and CD measurements. The ANOVA analysis showed there was no significant difference in the arithmetic means for the measurements between and within group A and the other groups (p > 0.05). Conclusion: The UV-C light exposure time of 10, 20, 30, and 40 minutes did not have any negative effect on the dimensional stability of the addition silicone dental impressions evaluated. Clinical significance: In the daily routine dental practice, dental impressions need to be washed and disinfected immediately after making to prevent cross-infections. The UV-C light has been proposed as a promising method for disinfection, but only a few studies have been published about its effect on the dimensional stability of dental silicones.

Aim: The purpose of the present study was to assess the bonding capacity and efficacy of acrylic teeth to denture bases following two different chemical surface treatments. Materials and methods: A two-metal mold measuring 35 mm in length and 12 mm in diameter was created specifically for the investigation in order to standardize the wax pattern-based tooth attachment at 45^°. Following standard protocol, 75 wax cylinder specimens were flasked, dewaxed, and surface treatment of teeth was done as follows with 25 samples in each group—group I: control group, group II: monomethyl methacrylate monomer group, group III: acetone group. The curing process was completed following the packing of the denture base material. The samples’ shear bond strength was assessed using a universal testing machine. Every sample was taken out when it fractured, and the shear load (Newton, N) was noted. The significance of the variation in applied shear load was assessed using one-way analysis of variance (ANOVA) and post hoc ANOVA Tukey's honestly significant difference (HSD) test at the 5% level of significance. Results: The maximum shear bond strength was found in the samples treated with acetone (183.21 ± 0.06) followed by samples treated with monomethyl methacrylate monomer (171.64 ± 0.12) and the control group (149.32 ± 0.04). A statistically significant difference was found between the different groups (p < 0.001). Conclusion: In conclusion, according to the current study's findings, acetone chemical surface treatment of acrylic teeth produced the strongest bond when compared with the control group and monomethyl methacrylate monomer. Clinical significance: In prosthodontic practice, artificial teeth regularly de-bond and separate from the denture base. A weak interface is produced when certain clinical conditions, such as ridge prominence, cause excessive cutting of the acrylic teeth and base. Where the denture base polymer meets the teeth's highly cross-linked matrix, it de-bonds adhesively. Therefore, the bonding between the acrylic teeth and the denture base material can be improved by the chemical surface treatment.

Aim: This study was designed to compare between the use of Khoury's bone shell technique vs titanium-reinforced PTFE membrane for 3D-ridge augmentation of atrophic posterior mandible. Materials and methods: Sixteen patients were equally and randomly assigned to either the Khoury or PTFE group. In Khoury group, a mandibular bone block was harvested, split and then fixed to augment the mandibular defect using osteosynthesis screws. In PTFE group, augmentation was achieved using Titanium-reinforced PTFE membranes fixed with bone tacks/screws. A mixture of autogenous and xenogenic graft material at a 1:1 ratio was used in both groups. Vertical and horizontal bone gain were obtained using cone-beam computed tomography (CBCT). Preoperative dimensions were compared with the final dimensions obtained 6 months postoperatively. Results: No significant complications or neurosensory dysfunction were encountered. A solitary patient in the Khoury group experienced limited wound dehiscence, which was treated conservatively. For both groups, there were no significant differences between preoperative and postoperative vertical (p = 0.849 and 0.569) and horizontal (p = 0.778 and 0.367) dimensions. Conclusion: No significant differences exist between the augmentation dimension which can be obtained using either Khoury of Ti-PTFE membranes. Clinical significance: Both approaches are delicate and necessitate surgical expertise and experience. Both techniques can be used to achieve predictable augmentation results with a low rate of complications.

Aim: This study aimed to evaluate the impact of digital vs traditional impression techniques on peri-implant vertical bone resorption in the creation of mandibular overdenture bases supported by four implants using CAD/CAM technology. Materials and methods: Twenty edentulous patients were placed in four mandibular implants and randomly divided into groups: (A) the control group (CIG) (n = 10); patients obtained CAD/CAM denture base using conventional impression technique and group (B) the study (DIG) group (n = 10); patients obtained CAD/CAM denture base using digital impression technique. Peri-implant vertical bone height was measured immediately (T0), 6 (T6), and 12 (T12) months after insertion. Peri-implant vertical bone loss (VBL) was calculated first 6 months (T1), the second 6 months (T2), and 1 year (T3) after insertion. Results: For both groups, the survival rates of inserted implants were 100%. The amount of VBL in the first year in both groups was within normal ranges. In both groups, VBL significantly decreased over time. The control group recorded significantly higher VBL than (DIG) group at T2 (p = 0.006) and at T3 (p = 0.005). Conclusion: Digital intraoral scanning technique may be considered a more beneficial registration method than traditional impression technique for the construction of CAD/CAM 4-implant-assisted overdenture base regarding the preservation of vertical bone levels. Clinical significance: Both digital intraoral scanners and conventional impression techniques can be used for the construction of CAD/CAM-implant-assisted overdenture bases regarding the preservation of peri-implant vertical bone resorption.

Aim: The study aimed to detect and quantify bisphenol A (BPA) leaching in salivary samples of patients undergoing clear aligner therapy (CAT) using four different commercially available sheets. Materials and methodology: Four different commercially available clear aligners namely Monoflex®, Erkodur®, Leone®, and Duran® were delivered to 20 volunteers who were grouped into (n = 5) group A, group B, group C, and group D, respectively. Salivary samples were collected immediately before aligner insertion (day 0) and at day 1, day 5, and day 7 after aligner wear. Comparisons were made between baseline (day 0) BPA levels and subsequent time points to assess the leaching kinetics of BPA from the clear aligners by liquid chromatography/mass spectrometry. Results: The overall mean leaching of 0.74 ± 0.33 ppm at T1 (day 1) was observed among four groups of aligners, while no leaching was detected at T5 (day 5) and T7 (day 7). Among the four groups, the highest leaching of 1.24 ppm was detected from Duran at T1 followed by Monoflex (0.76 ppm), Erkodur (0.56 ppm), and Leone (0.43 ppm). Conclusion: It can be concluded that leaching only during the first 24 hours of aligner usage was dominant compared to other time intervals. Among the aligners considered, Duran was found to be the least safe followed by Monoflex, Erkodur, and Leone. Clinical significance: Since aligners are expanding in usage it is important to consider their biocompatibility. Even though the results indicate minimal leaching of BPA, it has a cumulative negative effect when patients undergo prolonged treatment with aligners.

Aim: This study was done to clinically investigate the efficacy of glycyrrhizin-based intracanal medication (ICM) compared to calcium hydroxide Ca(OH)₂ and Ledermix on the bacterial counts inside the root canals of necrotic teeth with chronic periapical periodontitis. Methodology: Thirty-six patients having single-rooted and single-canaled necrotic teeth with chronic periapical periodontitis were enrolled in this research. Aseptic control measures were taken before clinical steps. Access cavity preparation was done. First bacteriological samples (S1) were collected immediately after access cavity preparation and before cleaning and shaping inside the root canals. Cleaning and shaping were performed on the root canals. Patients were randomly allocated into 3 groups according to the type of intracanal medicament used [Ca(OH)₂, Ledermix, Glycyrrhizin]. Second bacteriological samples (S2) were collected after 1 week from placing the ICMs. S1 and S2 were transferred to the lab of microbiology for culturing on blood agar dishes in anaerobic conditions, and the bacteria on the plates were enumerated as colony-forming units (CFUs) by the manual counting method. The anti-bacterial efficacy of the ICM was estimated by the percentage reduction in the bacterial colonies from S1 to S2. Results: All tested ICM documented a significant reduction in the CFUs from S1 to S2 (p < 0.05). Regarding S1, there was no significant difference between the three tested materials (p > 0.05). Regarding S2, Glycyrrhizin and Ledermix showed significantly lower CFUs than Ca(OH)₂. There was no significant difference between Glycyrrhizin and Ledermix. Conclusion: Under the conditions of the present study, Glycyrrhizin and Ledermix showed comparable antimicrobial effects that were better than the commonly used Ca(OH)₂ ICM. Glycyrrhizin may be a promising ICM. Clinical significance: Herbal medicine can be considered as an alternative antimicrobial material for root canal disinfection because it has many benefits, like low toxicity, absence of microbial resistance, and favorable antimicrobial efficacy. This study highlights the clinical efficacy of Glycyrrhizin as a promising ICM.

Aim: The present study aimed to evaluate the antimicrobial efficacy of silver nanoparticles infused with Azadirachta indica extract and chlorhexidine against red-complex periopathogens. Materials and methods: Neem leaf extraction was done followed by standardization to the synthesis of neem-infused silver nanoparticles and fractionation of compounds done by using thin layer chromatography to separate the mixture of neem leaf extract. Characterization of neem-infused silver nanoparticles was done by scanning electron microscopy and UV-Visible spectroscopy. The compound identified in neem-infused silver nanoparticles was gedunin which was confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. Determination of antibacterial activity done by disc diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. Group I—99% ethanolic extract, group II—neem-infused silver nanoparticles (NAgNPs), group III—chlorhexidine. Results: The relative inhibitory zone value for Tannerella forsythia (180) in neem-infused silver nanoparticles (group II) was greater when compared with other periopathogens Porphyromonas gingivalis (133) and Treponema denticola (160) than 99% ethanolic extract (group I), chlorhexidine (group III). Neem-infused silver nanoparticles (group III) showed superior antimicrobial activity against T. forsythia (19.3 ± 31.1547) and T. denticola (18±0) when compared with P. gingivalis (17.6 ± 0.5774). On evaluating MIC and minimum bacterial concentrations, P. gingivalis is more resistant than other pathogens in neem-infused silver nanoparticles (group III). Conclusion: Neem-infused silver nanoparticles exhibited superior antibacterial activity as compared with gold-standard chlorhexidine against red-complex periodontal pathogens. For MIC and MBC all the three periopathogens were effective but P. gingivalis was more resistant. Clinical significance: Antibiotics are effective against many drug-resistant bacteria. As a ready-made medicine, they can be used to treat many infections. Silver nanoparticles in drug delivery systems generally increase solubility, stability, and biodistribution, thereby increasing their effectiveness. Green synthesis using plant extracts as precursors to synthesize nanoparticles has proven to be environmentally non-hazardous combined with remarkably improved efficacy against bacterial and viral diseases. So neem-infused silver nanoparticles can be utilized as a drug delivery system. Hence, it can be used as a potential antibacterial ingredient in formulations for periodontal use like mouthwashes and gels for local drug delivery.

Aim: This study was performed to evaluate the regenerative capacity of demineralized bone matrix vs fat graft, both guided by pericardium membrane in alveolar cleft model in albino rats. Materials and methods: A total of 72 rats were required in this study. A surgical bone defect with a 7 mm length × 4 mm width × 3 mm depth was created as a model of an alveolar cleft, then the rats were divided randomly into four equal groups each group contained 18 rats: control group (defect only), the membrane group (the defect was covered by the pericardium membrane), the demineralized bone matrix (DBM) group (the defect was filled with DBM guided by pericardium membrane) and fat group (the defect was filled with a fat graft guided by the pericardium membrane). Around 6 rats from each group were euthanized after 2, 4, and 8 weeks. Skulls were scanned with cone beam computed tomography (CBCT) and harvested for histological evaluation with routine H&E immunohistochemical stains (Anti-osteocalcin and Anti-Wnt5a). The data was recorded and statistically analyzed by a two-way ANOVA. Results: The study showed a notable formation of new bone, and expression of OCN and Wnt5a were notably increased by time in the fat group. However, the density of bone grafts and OCN and Wnt5a expression decreased with time in the DBM group. Control and membrane groups showed negative OCN and Wnt5a immune-reactivity in the cleft site. Conclusion: Fat graft results were superior to DBM results with regard to mucosal closure and accelerated bone regeneration, and may represent an effective treatment for alveolar cleft reconstruction. Clinical significance: Finding an inexpensive, accessible, biocompatible and easily manipulated treatment for craniofacial reconstruction and fat graft fulfilled the desired aims. Further investigations with prolonged evaluation periods are needed.

Aim: Clinical and radiographic evaluation of the efficacy of platelet-rich fibrin (PRF) and treated dentin matrix (TDM) in regenerative endodontic treatment and periapical healing of nonvital immature permanent teeth with chronic apical periodontitis. Materials and methods: Twenty-four children aged between 7 and 11 years, each presenting with a nonvital immature permanent upper central incisor, were selected. They were randomly allocated into two groups (n = 12), group I (PRF) and group II (TDM). Baseline clinical findings were recorded, and preoperative cone-beam computed tomography (CBCT) was taken. Follow-up was done clinically for 15 months at 3-month intervals (3, 6, 9, 12, and 15 months), and CBCT was taken at the end of the 15-month follow-up. Root length, apical diameter, radiographic root area (RRA), and size of the periapical lesion were quantitively assessed at the end of follow-up period and compared to the preoperative CBCT. Results: Clinical success was 100% in both groups by the end of the follow-up period. Radiographically, after a 15-month follow-up, there was a significant increase in root length and RRA, and there was also a significant reduction in apical diameter and lesion size within each group (p < 0.05). However, there was no statistically significant difference between both groups regarding the mean percentage of increase in root length and mean percentage of reduction of apical diameter (p > 0.05). On the other hand, PRF showed more increase in RRA and more reduction in lesion size, with a statistically significant difference between both groups (p < 0.05). Conclusion: Both PRF and TDM were clinically successful. Platelet-rich fibrin showed better radiographic outcomes and periapical healing. Clinical significance: Platelet-rich fibrin is a viable scaffold to aid further root development and resolution of periapical lesions of nonvital immature permanent teeth. Further studies with different forms of TDM are needed to assess the efficacy of TDM in regenerative endodontic treatment of nonvital immature permanent teeth.

Aim: The aim of this study is to compare the fracture resistance of canine teeth restored using TRINIA Endocrowns with three different types of preparations (2, 3, and 4 intracanal preparations). Materials and methods: Thirty maxillary-extracted canines were collected. All teeth were fixed in orthodontic acrylic resin and decapitated at the level of the proximal cemento-enamel junction (CEJ). After being endodontically treated, specimens were distributed equally between 3 groups (n = 10) with different preparation depths (GT: 2 mm Intraradicular Preparation, GH: 3 mm Intraradicular Preparation, GF: 4 mm Intraradicular Preparation). Thirty TRINIA endocrowns were dry milled. After surface treatment, all endocrowns were bonded to their corresponding roots using Permaflo a dual-cure resin cement. Each specimen was then fixed in the lower part of a universal testing machine with a load cell of 5 KN, at an angle of 45 degrees to the tooth long-axis at 0.5 mm/min crosshead speed. Failure loads were recorded in Newton's. Data were recorded, organized, and statistically investigated. Results: Shapiro–Wilk tests revealed that the data were not normally distributed. Descriptive statistics revealed a high mean fracture resistance of GH (647 N), then GT (475.6 N), and finally GF (353.9 N). The Kruskal–Wallis test revealed a significant difference that existed between the groups being studied (p = 0.036). Conclusion: TRINIA endocrowns with intracanal preparations of 2 and 3 mm provide more promising fracture resistance than those with intracanal preparations of 4 mm as a way of treating of root-canal-treated maxillary canines. TRINIA endocrowns (2 and 3 mm intracanal preparations) are as promising as fiber posts and all ceramic crowns in terms of fracture resistance. TRINIA endocrowns with 2 mm intracanal preparations are mostly reparable after failure, but those of 3 and 4 mm are mostly irreparable after failure. Clinical significance: Modifying endocrowns to have intraradicular projections, simulating Nayyar core, may improve the success and longevity of endocrowns in anterior teeth.

Aims: This cross-sectional retrospective study was conducted to assess the differences in the microarchitecture of the trabecular bone of the posterior mandibular region at dentulous and edentulous sites with the help of fractal dimension (FD) and lacunarity using cone-beam computed tomography (CBCT). Materials and methods: Ninety CBCT scans were analyzed for the purpose of the present study. Inclusion criteria included subjects with unilaterally missing mandibular molars or premolars and an with intact contralateral opposing tooth. The coronal view of the dentulous and edentulous sites was used, and the region of interest (ROI) was selected 2.6 mm below the apex of the tooth present. These images were then transferred to ImageJ Software, and fractal analysis was done using the box-counting method of the FracLac plug-in. A paired samples t-test was performed to compare the means of FD and lacunarity, and a Kendall correlation was performed to check correlations. A p-value less than 0.05 was considered to indicate statistical significance. Results: Statistical analysis revealed that the mean FD of the edentulous side was significantly greater than that of the dentulous side (p-value = 0.011). Additionally, the mean lacunarity of the edentulous side was marginally significantly greater than that of the dentulous side (p-value = 0.089). A significant negative correlation was detected between the FD and lacunarity of the edentulous region (p-value = 0.017), and a marginally significant negative correlation was detected between edentulous lacunarity and dentulous lacunarity (p-value = 0.081). Conclusion: The differences in occlusal forces exerted in dentulous and edentulous regions can lead to a change in the trabecular pattern of the bone in these regions. This change in the microarchitecture of bones can be detected by FD and lacunarity, which can further help us assess changes pre- and post-implant. Clinical significance: The advanced technology, the assessment of microarchitecture of the bone has been made easy, using FD and lacunarity, as done in the present study. This analysis can further aid us in both pre- and post-implant analysis to prevent failure of the implant.

Aim: This study aimed to synthesize and characterize a novel Bis-GMA analog, termed P-Bis-GMA, through structural modification by replacing hydroxyl (–OH) groups with phosphonooxy [–O–P(=O)(OH)₂] groups and to evaluate and compare its viscosity with Bis-GMA. Materials and methods: Bis-GMA, triethylamine, dichloromethane, and phosphoryl chloride were utilized for the synthesis of P-Bis-GMA through phosphorylation. Fourier discerned the chemical structure of the synthesized P-Bis-GMA transform infrared spectroscopy (FTIR), and its viscosity was assessed by rheometry in oscillatory shear mode over a frequency sweep range of 0.1–100 (ω, rad/s) at 25°C with a 25 mm parallel plate design and a 0.5 mm gap. The data was recorded and statistically analyzed. Results: The FTIR analysis confirmed the successful synthesis of P-Bis-GMA, evidenced by the disappearance of hydroxyl (–OH) peaks and the emergence of phosphonooxy [–O–P(=O)(OH)₂] peaks in the P-Bis-GMA. Rheological testing demonstrated a notable reduction in viscosity for P-Bis-GMA (436.62 Pa.s) when compared to conventional Bis-GMA (1089.02 Pa.s), indicating improved handling characteristics. Conclusion: P-Bis-GMA was successfully synthesized by phosphorylation reaction where the –OH groups responsible for the high viscosity in the Bis-GMA were replaced with the [–O–P(=O)(OH)_2] groups with significantly reduced viscosity. Clinical significance: The development of P-Bis-GMA holds promise for simplifying dental procedures by reducing chairside time with uncooperative children. The P-Bis-GMA-based composites possess self-adhering properties thereby eschewing the etching and bonding procedures with reduced moisture contamination of the restoration during bonding. This ultimately leads to better clinical outcomes and improved patient experiences by reducing technical vulnerabilities.

Aim: This case series was to describe the use of surgical extrusion for three different cases as a technique to re-establish the biological width in patients with insufficient crown height. Background: Surgical extrusion serves as an important means to reestablishing a proper biological width. Such method provides an excellent alternative for the restoration of teeth with insufficient ferrule and ensuring a suitable dental restoration. Cases descriptions: This case series describes the management of three different cases with compromised teeth #25, #35, and #44, respectively. The approach involved the surgical extrusion of the compromised sites from subgingival to supragingival and the splinting of the teeth using a semi-rigid splint. A successful prognosis was observed on follow-up visits. Conclusion: This technique is a good alternative for general practitioners because of its easy implementation and time efficiency. In addition, the method requires less equipment and provides for adequate space for the re-establishment of biological width. Clinical significance: Such technique can re-establish a healthy biological width, the existing occlusion can be maintained without alterations, and it demonstrated the suitability of surgical extrusion technique in such clinical situations. Case selection is equally important. Cases with single-rooted teeth with fractures or caries in proximity to the marginal bone level without vertical root fractures generally provide positive outcomes on providing this treatment.

Aim: To analyze the scientific production related to the use of botulinum toxin (BTX-A) in the management of bruxism and evaluate its scope, impact, networks, and new research trends. Materials and methods: A descriptive and retrospective study of publications indexed in Scopus from January 2018 to May 2024 was conducted. The bibliometric indicators evaluated were a number of publications, citations, h-index, SCImago Journal Rank 2022, CiteScore 2022, Lotka's Law, Bradford's Law, and keyword co-occurrence analysis. Data were processed using SciVal and VOSviewer. Results: We obtained 98 publications, including original articles, reviews, and other types of documents. Among the most productive authors, most were from South Korea and Turkey. Wonkwang University (South Korea) had the highest number of publications, while Baylor College of Medicine (USA) had the highest impact with 66.5 citations per publication. Toxins had the highest number of publications and the best Cite Score in 2022. Six main topics related to BTX-A in bruxism were identified, highlighting “reviews,” “electromyography” and “controlled clinical trials”. Conclusions: The use of BTX-A for the treatment of bruxism has generated increasing interest and scientific output in recent years, especially in South Korea and Brazil. However, there is a disparity in the productivity of authors, with most authors presenting only one publication. Clinical significance: This study highlights the need for further research and collaborations to optimize clinical practice and better understand the efficacy and management of BTX-A for treating bruxism.

Aim and background: This systematic review examined the current literature to evaluate the fracture resistance of the tooth fragments reattached using fiber-reinforced composites (FRC). Materials and methods: An electronic search was performed on Scopus, PubMed, and Web of Science databases according to specific inclusion and exclusion criteria to identify relevant articles to be included until January 2023. Articles with full text available in the English language for randomized control studies, observational studies, retrospective studies, and in vitro studies conducted on permanent human teeth were selected. The risk of bias was assessed in all studies using the OHAT tool. Results: Out of 16 search results, seven in vitro studies with a total of 415 samples were included in the review. Three studies reported that reinforcement using rigid FRC posts improves fracture resistance of reattached anterior teeth, three studies reported that reinforcement using flexible fiber bundles enhances the fracture strength of reattached posterior teeth and one study reported that the use of flexible polyethylene fibers improves fracture resistance in molars with reattached cusps. Conclusion: Within the limitations of the studies included in the review, there is low-quality evidence that reinforcement of reattached fragments using FRC posts or fibers improves fracture resistance. Clinical significance: The reattached fractured fragments may be susceptible to re-fracture. The use of FRC to reinforce the resin composite used for reattachment may enhance the bond strength and increase resistance to fracture.