Influence of chitosan and Cissus quandrangularis coating on osseointegration in titanium implants in rabbits: A preclinical in vivo study

BACKGROUND

Titanium (Ti) implants has been criticized for the tiring wait for osseointegration, often making the patient reconsider implant treatment. Surface treated Ti implants are emerging as a promising solution with superior osseointegration, early loading protocols and shortened period of edentulousness. The aim of this study is to assess the osseointegration of Ti surface coated with novel Cissus quandrangularis Chitosan Hydrogel (CqChH) compared to Commercially pure (Cp) implants.

METHODS

24 Cp Ti implants were divided into 2 subgroups (n = 12). The test group consisted of Ti implants surface treated with the novel hydrogel and control group consisted of Cp Ti implants. 3 % CqChH was prepared and was coated on the Ti implants prior to placement in the femur and tibial heads of rabbits. Implant Stability Quotient (ISQ) was recorded at the 6th and 12th week. Animals were sacrificed and subjected to Removal Torque Quotient (RTQ). The samples were retrieved en bloc and stained for histopathologic analysis. The collected data was subjected to statistical analysis using Unpaired student t-Test.

RESULTS

At the end of 6th week CqChH coated implants did not show any statistically significant difference in both ISQ and RTQ values compared to Cp ones. However, at the end of the 12th week CqChH coated implants demonstrated significantly higher ISQ (73.91 ± 4.39) and RTQ (75.96 ± 14.10) compared to Cp ones.

CONCLUSIONS

This study demonstrated that the novel hydrogel coating applied to the implant's surface exhibited not only enhanced bone regeneration but also elicited a new bone formation.

Remineralising potential of Ocimum basilicum varnish and fluoride varnish on initial enamel caries: An in vitro microscopic study

Background

The focus of caries research has switched to early identification and non-invasive treatment of carious lesions.

Aim

This study aimed to evaluate and compare the remineralising potential of Ocimum (O.) basilicum varnish and fluoride varnish on initial enamel caries.

Method

The authenticated O. basilicum seeds were procured from a repository, and the extract was prepared using the Soxhlet method, which was vortexed with Indian Pharmaceutical (IP)-graded chemicals to obtain varnish. Extracted premolar tooth samples were divided into three groups of 33 each after demineralisation with a pH of 4.5 for 48 hours at 37°C. Each group was subjected to remineralisation twice daily with respective agents for 4 minutes for 30 consecutive days. Each sample was ground-sectioned through an enamel window. The lesion depth was measured using a light microscope (Leica™ DM2500) and ImageJ software. The data were evaluated using analysis of variance (ANOVA) and post hoc analysis.

Results

The mean (± SD) pre-treatment lesion depth across the groups ranged from 242.11 ± 26.144 μm to 352.66 ± 34.531 μm. The highest lesion depth recovery rate of 45.938% was recorded for the fluoride varnish group, followed by 36.015% in the O. basilicum varnish group, which was statistically significant by Tukey's post hoc analysis (p < 0.001). The gingival fibroblast cells were viable by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay.

Conclusion

The O. basilicum varnish demonstrated a homogenous layer of mineral deposition. However, the remineralising efficacy was slightly lesser than that of the fluoride varnish. Hence, the novel O. basilicum-based remineralisation agent appears to have potential as a non-invasive alternative to topical fluorides in the therapy of early caries lesions.

Histochemical and Immunohistochemical Analysis of Collagen Fibers and Microvascular Density in Various Grades of Oral Submucous Fibrosis

Background and Objective:

This study was aimed to evaluate the collagen fibers qualitatively and its correlation with microvascular density in various grades of oral submucous fibrosis (OSMF).

Material and Methods:

The present study comprised of total 40 cases of oral submucous fibrosis. Picrosirius red staining was done on all the specimens’ sections. They were analyzed for the colour and orientation of collagen fibers. Morphometric measurements were done using image analysis on immunohistochemical stained sections for Factor VIII-related antigen and analyzed for microvascular density.

Results:

Picrosirius red polarizing microscopy results revealed that there was a shift in the colour of collagen fibers from greenish yellow to orange red and red colour as the severity of the oral submucous fibrosis increased. The collagen fibers showed mixed orientation in early oral submucous fibrosis and parallel orientation in advanced oral submucous fibrosis. There was a significant decrease in microvascular density from early to advanced oral submucous fibrosis.

Conclusion:

The change in the colours and orientation of collagen fibers in early and advanced oral submucous fibrosis could be attributed to the fibre thickness, type of collagen, alignment and packing, cross-linking of the fibers and the section thickness. However, in advanced cases the vascularity is reduced which may predispose to epithelial atrophy and subsequent malignant changes.

An immunohistochemical study of basement membrane heparan sulfate proteoglycan (perlecan) in oral epithelial dysplasia and squamous cell carcinoma

BACKGROUND

Basement membrane heparan sulfate proteoglycan (perlecan) has been demonstrated in precancer lesions and carcinomas of oral cavity. It helps in malignant transformation of epithelial cells. The aim of our study was to understand the immuno-localization of perlecan in oral dysplastic epithelium and oral carcinomas.

MATERIALS AND METHODS

A total of 50 cases comprising 10 normal mucosa, 20 dysplastic mucosa, and 20 oral squamous cell carcinomas (OSCC) were included in the retrospective study. They were examined for the presence of perlecan protein core by immunohistochemistry using monoclonal antibody. Interpretation of the pattern of staining was done, and majority of the observations were taken for statistical analysis.

RESULTS

In normal epithelium, perlecan was found to be present in basal layer at the cell border. In dysplastic epithelium, it was present in suprabasal layers also. With the increase in severity of dysplasia, its expression was more in suprabasal layers, and the immuno-localization was found to be at cell border and cytoplasm. In OSCC cases, perlecan was present in stroma and tumor islands.

CONCLUSION

It was deduced from the above results that perlecan helps potentially in dysplastic changes of epithelial cells. It gets accumulated within the cell and intercellular spaces and serves as a reservoir for various growth factors. In OSCC, it breaks down and releases growth factors, which help in tumor progression, angiogenesis, and metastasis of the carcinoma.

Oral hyaline ring granuloma: a case report

An unusual granulomatous inflammatory lesion characterised by the presence of ring shaped hyaline bodies accompanied by foreign body giant cell reaction has been mentioned in the literature. A lack of agreement exists on the nature of these hyaline rings. Opinions ranging from their being hyaline degenerative blood vessels to remains of leguminous cells have been postulated. Although the nature and origin of these bodies is uncertain, there is now considerable evidence that they represent, at least in part, vegetable material, especially pulses, that have been implanted in the tissues. An inflammatory oral lesion in a 17-years-old male patient caused due to traumatic implantation of the vegetable matter (sugar cane) has been reported in this paper. Based on the histological finding of a granulation tissue surrounding a hyaline ring the lesion was diagnosed as hyaline ring granuloma.

Perlecan (basement membrane heparan sulfate proteoglycan) and its role in oral malignancies: an overview

Perlecan means pearl-like structures. Perlecan is a large proteoglycan (400-500 kDa) present in virtually all vascularized tissues with a distribution that is primarily confined to basement membranes including those of oral mucosa. It is a basement membrane-type heparan sulfate proteoglycan. Perlecan is synthesized by basal cells and fibroblasts adjacent to the basal lamina . Perlecan is also synthesized by vascular endothelial and smooth muscle cells present in the extracellular matrix. It has been demonstrated in recent years that perlecan is distributed in the stromal space of various pathophysiological conditions. The complex pleiotropy of perlecan suggests that this gene product is involved in several developmental processes, at both early and late stages of embryogenesis, as well as in cancer and diabetes. In the oral cavity, perlecan expression is reported to basal cells in normal mucosa and its expression increases in precancer and cancerous conditions. It is also expressed in various odontogenic tumors such as ameloblastoma, keratocyst odontogenic tumor, and also salivary gland tumors such as adenoid cystic carcinoma, mucoepidermoid carcinoma, etc.

Immunohistochemical expression of Tenascin in embryogenesis, tumorigenesis and inflammatory oral mucosa

OBJECTIVE

Tenascin is a large extracellular matrix glycoprotein that plays specific role in cell matrix interaction. This protein is mainly attracted because of its oncofetal predominance expression at epithelial-mesenchymal interaction and also been associated with inflammatory response. Thus the aim was to study the expression of Tenascin within the oral cavity in a developing tooth, normal oral mucosa, squamous cell carcinoma and inflammatory mucosa and further to compare its expression in inflammatory mucosa with that of squamous cell carcinoma.

DESIGN

A total numbers of 92 cases were included, with 22 being all morphological stages of developing tooth, 10 cases of normal oral mucosa, 30 cases each of inflammatory gingival hyperplasia and oral squamous cell carcinoma. The intensity and pattern of expression was assessed immunohistochemically using anti-human mouse monoclonal Tenascin antibody.

RESULTS AND CONCLUSION

Tenascin expression in developing tooth was seen mainly at epithelial-mesenchymal junctions, but temporally reduced at cap stage. In normal mucosa TN expression was restricted only at basement membrane zone. Inflammatory gingival hyperplasia intensity of expression was enhanced at the juxtraepithelial stroma and showed reticular pattern of expression. In oral squamous cell carcinoma, intensity of expression was seen in superficial front of the stroma and also around tumour islands with intraepithelial expression and predominantly showed fibrillar pattern of expression. Furthermore, Tenascin expression was noticed around neovascularization. Hence, there is a regulatory system in Tenascin expression and plays a vital role in embryogenesis, tumerogenesis and inflammation in remodelling the stroma for cell migration and also for healing.

Dentin dysplasia: single-tooth involvement?

Dentin dysplasia is a genetic defect of dentin formation inherited as an autosomal dominant trait. It is characterized by normal enamel but atypical dentin formation with abnormal pulpal morphology. Once thought to be a single entity, dentin dysplasia has now been divided into type I (radicular) and II (coronal). Type I is by far the more common. Both types include multiple/generalized involvement of primary and permanent dentition. Combinations of both types have also been described in the literature. Four distinct forms of dentin dysplasia type I and 1 form of dentin dysplasia type II are identified. Although there seems to be no need to identify more than 2 distinct types of this relatively rare inherited defect of human dentin, the possible existence of additional forms of the disease cannot be ruled out. Here is a case report of dentin dysplasia in a single tooth, with crown and roots of normal dimensions, associated with severe pain and mobility and histologically involving both coronal and radicular dentin. Focal odontoblastic dysplasia or dentin dysplasia type III could be the new entity.