Assessment of Toxicity of Green Synthesized Silver Nanoparticle-coated Titanium Mini-implants with Uncoated Mini-implants: Comparison in an Animal Model Study.

AIM: To assess the potential for systemic toxicity when silver nanoparticle-coated mini-implants were implanted in Wistar albino rats conducted as a comparative study in the animal model by assessing the blood biochemistry, liver and kidney function, and histology of the implanted site. MATERIALS AND METHODS: The surface of the mini-implant was coated with a green-mediated silver nanoparticle. Uncoated mini-implants were placed in two groups of eight Wistar albino rats, and silver nanoparticle-coated mini-implants were placed in another eight rats. The bone's general conditions, blood biochemistry assessing for ALT, AST, GPT, GOT, and histological sections using H and E stain and Masson's Trichrome stain were examined at 7, 14, and 28-day intervals. RESULTS: The creatinine, urea, ALP, and ALT showed no signs of systemic toxicity during the 28-day follow-up period in the Wistar rats both in the test and control groups. The histological evaluation, which was conducted using HE and MTS stain, revealed osteogenesis and adequate healing of the insertion site in the group where coated mini-implant was placed. The bone sample revealed no abnormalities in the control group with uncoated mini-implants. CONCLUSION: Green synthesized silver nanoparticle-coated mini-implant does not cause systemic toxicity as indicated by no abnormalities in the levels of creatinine, urea, ALT, ALP, GPT, and GOT. The bone histology indicates that the coated mini-implants placed in animal bone healed with adequate osteogenesis. CLINICAL SIGNIFICANCE: Silver nanoparticles have potential for antimicrobial activity. Mini-implants placed as temporary anchorage devices in orthodontics often fail due to inflammation and plaque. Silver nanoparticle-coated mini-implants would reduce the risk of mini-implant failure as it would have antimicrobial potential and eliminate this cause for failure of mini-implants. How to cite this article: Sreenivasagan S, Subramanian AK, Mohanraj KG, et al. Assessment of Toxicity of Green Synthesized Silver Nanoparticle-coated Titanium Mini-implants with Uncoated Mini-implants: Comparison in an Animal Model Study. J Contemp Dent Pract 2023;24(12):944-950.

Therapeutic potential of Mucuna pruriens (Linn.) on ageing induced damage in dorsal nerve of the penis and its implication on erectile function: an experimental study using albino rats.

OBJECTIVE: To study the effect of ethanolic seed extract of Mucuna pruriens on damaged dorsal nerve of the penis (DNP) in aged rat in relation to penile erection. METHODS: The rats were divided into four groups Young (3 months), Aged (24 - 28 months), Aged + M. pruriens, and Young + M. pruriens (200 mg/kg b.w/60 days) and were subjected to the hypophysial - gonadal axis, nerve conduction velocity (NCV), and penile reflex. DNP sections were stained with nitric oxide synthase (nNOS), nicotinamide adenine dinucleotide phosphate (NaDPH) diaphorase, androgen receptor (AR), and osmium tetroxide. Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) staining, electron microscopy(EM) and histometric analyses were done. RESULTS: Significant disturbance in hypophysial - gonadal axis was noted in aged rat. With reduced number of myelinated fibers, diameter, vacuolization, indentation of the myelin sheath, and degeneration. nNOS and its cofactor (NaDPH diaphorase) were reduced in aged rat DNP. NCV was slow in aged rats and concomitant poor penile reflex was also noted. AR showed reduced expression in aged rat DNP when compared to young and control groups. TUNEL positive cells were increased in aged rat DNP. These pathological changes were remarkably reduced or recovered in M. pruriens treated aged rats. CONCLUSIONS: The results indicate a multi-factorial therapeutic activity in penile innervations towards sustaining the penile erection in the presence of the extract in aged rats and justifying the claim of traditional usage.

Histologic Assessment of a Fast-Set Mineral Trioxide Aggregate (MTA) and Two Novel Antibacterial-Enhanced Fast-Set MTAs for Apexification and Periapical Healing of Teeth With Incomplete Root Formation in a Rat Model: An In Vivo Animal Study.

Background Pulp necrosis in incomplete root formation halts dentine development, resulting in larger canals with fragile walls and an open apex, complicating canal instrumentation and apical stop formation. Bioactive endodontic cements such as mineral trioxide aggregate (MTA) are crucial for creating artificial apical barriers or inducing apical foramen closure, but challenges remain regarding their antimicrobial efficacy and cytotoxicity. Modifications to MTA formulations aim to address these concerns. Methods This in vivo animal study involved 80 Wistar albino rats, with incomplete root formation induced by pulp exposure. Rats were divided into four groups receiving different MTA formulations for apexification: conventional MTA, modified MTA, and MTA enhanced with metronidazole or doxycycline. Histopathological evaluations were conducted at seven and 28 days post-treatment to assess calcific barrier formation, inflammatory reactions, and antimicrobial efficacy. Results By day 7, modified MTA formulations exhibited enhanced antibacterial activity compared to conventional MTA (p = 0.000), with fewer inflammatory reactions and microorganisms. By day 28, modified formulations showed superior calcific barrier formation, particularly in the metronidazole- and doxycycline-enhanced groups compared to conventional MTA (p = 0.000). These outcomes suggest that modifications to MTA formulations improve antimicrobial efficacy and calcific barrier formation in vivo. Conclusion Novel modified MTA formulations, particularly those enhanced with metronidazole or doxycycline, exhibit superior antibacterial efficacy and calcific barrier formation compared to conventional MTA. Further long-term studies are warranted to validate these findings for potential clinical translation.

Morphometric analysis of Bonwill's triangle and its dental applications in dry human mandible bones.

Bonwill's triangle is an imaginary equilateral triangle formed when the centers of two condyles and each condyle with the medial mandibular incisal midpoint are joined. The dimensions of the tooth, with other bones of cranium, and the entire anatomical structure of body are in persistent association with the distance of the borders of the triangle. It can be used to study articulation of the mandible, complete dentures, and dental occlusion and can be related when treating mandibular fractures. The aim is to analyze the variations in the length of Bonwill's triangle in dry human mandibles and its dental implications. Forty dry human mandibles were taken to carry out this study. Distances between the center of the right condylar process to the inner medial mandibular incisal midpoint (A), the distance between the center of the left condylar process to the inner medial mandibular incisal midpoint (B), and the distance between the centers of right and left condylar process of mandible (C) were measured with the aid of digital vernier caliper. The statistics was evaluated and observed using the statistical analysis software SPSS (Version 20.0) and the mean and standard deviation was calculated. The mean length between right condyle center and medial mandibular incisal midpoint is 97.76 mm, between left condyle center and medial mandibular incisal midpoint is 98.55 mm, and between the right and left condyle centers is 97.39 mm. The values are almost equal to 4 inches. The mandibular measurements serve as an important factor for many clinical conditions especially related to dentistry. The results of this study can be of great significance when treating mandibular fractures and defects.

Morphometric analysis of oculomotor triangle in dry human skulls and its clinical applications.

The oculomotor triangle is denoted as the "Triangle of Hakuba" or the "Hakuba's Triangle." This oculomotor triangle is a significant anatomical landmark. Oculomotor nerve, abducens nerve and part of the internal carotid artery (ICA) lie in this triangle. The determination of this analysis is to calculate the oculomotor triangle in dry processed skull bones of the south Indian population and its clinical significance. Fifty-one processed skulls of human origin were received from Anatomy Department, Basic Medical Sciences, Saveetha Dental College. Length from anterior-clinoid process (ACP) to posterior-clinoid process (PCP), length from PCP to APEX, and length from ACP to APEX were measured. Paired samples t-test was considered to analyze the values between the right triangle with the left triangle. From the measurements taken, the mean for the left side of the oculomotor triangle, ACP to PCP was 8.0591 ± 0.52 mm and the right side was 7.5482 ± 0.52 mm. The mean left side of the oculomotor triangle, measured from PCP to APEX was 6.73 ± 0.48 mm and the right side was 6.55 ± 0.72 mm. The mean of the left side of the oculomotor triangle, measured from ACP to APEX was 15.94 ± 0.682 mm and the right side was 16.21 ± 0.747 mm. Through this paired triangle of the cranial cavity, the horizontal section of ICA may be correlated with numerous vascular-related pathological considerations.

Efficacy of Graphene-Based Nanocomposite Gels as a Promising Wound Healing Biomaterial.

The development of biocompatible nanocomposite hydrogels with effective wound healing/microbicidal properties is needed to bring out their distinguished characteristics in clinical applications. The positive interaction between graphene oxide/reduced graphene oxide (GO/rGO) and hydrogels and aloe vera gel represents a strong strategy for the advancement of therapeutic approaches for wound healing. In this study, the synthesis, characterization, and angiogenic properties of graphene-based nanocomposite gels have been corroborated and substantiated through several in vitro and in vivo assays. In this respect, graphene oxide was synthesized by incorporating a modified Hummer's method and ascertained by Raman spectroscopy. The obtained GO and rGO were uniformly dispersed into the aloe vera gel and hydrogel, respectively, as wound healing materials. These formulations were characterized via in vitro bio-chemical techniques and were found suitable for the appropriate cell viability, attachment, and proliferation. In addition, in vivo experiments were conducted using male Wistar rats. This revealed that the GO/rGO-based gels stimulated wound contraction and re-epithelialization compared to that of the non-treatment group. From the study, it is suggested that GO/rGO-based aloe vera gel can be recommended as a promising candidate for wound healing applications.