Micro-Raman spectroscopy analysis of dentin remineralization using eggshell derived nanohydroxyapatite combined with phytosphingosine.

The aim of this study was to assess the remineralization efficacy of chicken eggshell-derived nano-hydroxyapatite (CEnHAp) combined with phytosphingosine (PHS) on artificially induced dentinal lesions. PHS was commercially procured whereas CEnHAp was synthesized using microwave-irradiation method and characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), high-resolution scanning electron microscopy-energy-dispersive X-ray spectroscopy (HRSEM-EDX), and transmission electron microscopy (TEM). A total of 75 pre-demineralized coronal dentin specimens were randomly treated with one of the following test agents (n = 15 each): artificial saliva (AS), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), CEnHAp, PHS, and CEnHAp-PHS under pH cycling for 7, 14, and 28 days. Vickers microhardness indenter, HRSEM-EDX, and micro-Raman spectroscopy methods were used to assess the mineral changes in the treated dentin samples. Data were submitted to Kruskal-Wallis and Friedman's two-way analyses of variance (p < 0.05). HRSEM and TEM analysis depicted irregular spherical structure of the prepared CEnHAp with a particle size of 20-50 nm. The EDX analysis confirmed the presence of Ca, P, Na and Mg ions. The XRD pattern showed the characteristic crystalline peaks for hydroxyapatite and calcium carbonate that are present in the prepared CEnHAp. Dentin treated with CEnHAp-PHS revealed highest microhardness values along with complete tubular occlusion compared to other groups at all test time intervals (p < 0.05). Specimens treated with CEnHAp showed increased remineralization than those treated with CPP-ACP followed by PHS and AS groups. The intensity of mineral peaks, as observed in the EDX and micro-Raman spectra, confirmed these findings. Further, the molecular conformation of the collagen's polypeptide chains, and amide-I and CH2 peaks attained peak intensities in dentin treated with CEnHAp-PHS and PHS whereas other groups revealed poor stability of collagen bands. Microhardness, surface topography, and micro-Raman spectroscopy analyses revealed that dentin treated with CEnHAp-PHS have an improved collagen structure and stability as well as highest mineralization and crystallinity.

Using a Composite Graft of Natural 15% Chitosan Gel in the Management of Intrabony Defects: A Case Series.

INTRODUCTION: The purpose of this study was to compare effects of smoking and smokeless forms of tobacco consumption (tobacco chewing) on periodontal disease parameters and response of these subjects to non-surgical periodontal therapy. MATERIALS AND METHODS: Ten patients aged between 30 and 55 years with intrabony defects greater than or equal to 3 mm and pocket probing depth (PPD) greater than or equal to 5 mm were selected. All participants received chitosan gel (15% w/v) plus bovine porous bone mineral as a composite bone graft. Clinical and radiographic measurements were recorded at baseline, 3 months after healing and at 6 and 9 months. Significance was set at 0.05. RESULTS: After nine months, all the defects treated with this combination showed PPD reduction of 5.30 ± 0.822 mm, relative clinical attachment level (CAL) gain of 5.80 ± 0.499 mm, reduction in intrabony defect (IBD) depth of 3.00 ± 0.497 mm and defect resolution of 78.32 ± 5.80 %, all of which were statistically significant. CONCLUSION: Within the limits of this study, this case series study suggests that chitosan gel, along with bovine porous bone mineral, has a promising role to play in periodontal regeneration.

The Autosomal Dominant Inheritance of Hereditary Gingival Fibromatosis: A Case Report.

Hereditary gingival fibromatosis (HGF) is a rare disorder characterized by progressive and varying degrees of gingival overgrowth. Oral manifestations vary from minimal to generalized enlargement, and HGF may occur as an isolated disorder or a feature of a syndrome. Unaesthetic appearance and functional impairment due to excessive gingival tissue dictate the need for surgical intervention. This article describes a family with three generations afflicted with a non-syndromic form of HGF with distinctive clinical, histological characteristics. Further, it highlights the need for genetic analysis and appropriate surgical technique to manage gingival enlargement and avoid recurrence.

Surface enhanced vibrational spectroscopy and first-principles study of L-cysteine adsorption on noble trimetallic Au/Pt@Rh clusters.

The Rh shell of the Au/Pt/Rh trimetallic nanoparticles induces a wide variety of interesting surface reactions by allowing the adsorption of amino acids like L-cysteine (L-Cys). We present a snapshot of theoretical and experimental investigation of L-Cys adsorption on the surface of noble trimetallic Au/Pt@Rh colloidal nanocomposites. Density functional theoretical (DFT) investigations of L-Cys interaction with the Rhodium (Rh) shell of a trimetallic Au/Pt@Rh cluster in terms of geometry, binding energy (E(B)), binding site, energy gap (E(g)), electronic and spectral properties have been performed. L-Cys establishes a strong interaction with the Rh shell. It binds to Rh by the S1-site, which makes a stable L-Cys-Rh surface complex. DFT can be taken as a valuable tool to assign the vibrational spectra of the adsorption of L-Cys on trimetallic Au/Pt@Rh colloidal nanocomposites and mono-metallic Rh nanoparticles. Surface-enhanced infrared spectroscopy (SEIRS) with L-Cys on a Rh6 cluster surface has been simulated for the first time. Experimental information on the L-Cys-Rh surface complex is included to examine the interaction. The experimental spectral observations are in good agreement with the simulated DFT results. Characterization of the synthesized trimetallic Au/Pt@Rh colloidal nanocomposites has been done by high-resolution transmission electron microscopy (HR-TEM) with selected area electron diffraction (SAED) pattern, energy dispersive X-ray (EDX) spectroscopy, dynamic light scattering (DLS) measurements, zeta potential, zeta deviation analysis and UV-visible (UV-Vis) spectroscopic studies.

Room temperature synthesis and optical studies on Ag and Au mixed nanocomposite polyvinylpyrrolidone polymer films.

Optical properties of silver, gold and bimetallic (Au:Ag) nanocomposite polymer films which are prepared by chemical method have been reported. The experimental data was correlated with the theoretical calculations using Mie theory. We adopt small change in the theoretical calculations of bimetallic/mixed particle nanocomposite and the theory agrees well with the experimental data. Polyvinylpyrrolidone (PVP) was used as reducing and capping agent. Fourier transform infrared spectroscopy (FTIR) study reveals the presence of different functional groups, the possible mechanism that leads to the formation of nanoparticles by using PVP alone as reducing agent. Optical absorption spectra of Ag and Au nanocomposite polymers show a surface plasmon resonance (SPR) band around 430 and 532 nm, respectively. Thermal annealing effect on the prepared samples at 60 °C for different time durations result in shift of SPR band maximum and varies the full width at half maximum (FWHM). Absorption spectra of Au:Ag bimetallic films show bands at 412 and 547 nm confirms the presence of Ag and Au nanoparticles in the composite.

Arterial occlusion precipitated by cisplatinbased chemotherapy.

Cisplatin-based therapy is curative in testicular cancer. Adverse effects of cisplatin-based chemotherapy include dose-dependent myelosuppression, nephrotoxicity, neurotoxicity, and ototoxicity. By contrast, chemotherapy-associated vascular complications are unpredictable. Few incidents of digital gangrene with cisplatin have been reported. Here, we present a patient who developed arterial occlusion leading to gangrene of the toe after cisplatinbased chemotherapy.

Role of angiogenetic markers to predict neck node metastasis in head and neck cancers.

Angiogenesis plays a key role in the initiation of growth and metastatic process in cancers. The angiogenic switch may be one of the earliest events in conferring a metastatic potential to the tumor. Further evolution in this multi-step cascade is controlled by the positive and negative regulators of angiogenesis. Recent advances in molecular biology have given a better insight into the mechanisms governing head neck cancer with promising data elaborating the role of angiogenesis. Metastasis to neck nodes is a very important determinant of prognosis, and is more frequently encountered than distant metastasis in head and neck cancers. Systematic PUBMED search of English-language literature of studies involving humans between 1990 and 2008 using the Mesh terms 'pathologic neovascularization', 'head and neck neoplasms', 'lymphatic metastasis' was performed. Quality assessment of selected studies included clinical pertinence, publication in peer reviewed journals, adequate number of enrolled patients. The present article reviews the utility value of various angiogenic parameters and markers that have been utilized to predict regional metastasis including micro vessel density, positive and negative regulators of angiogenesis, and genetic markers for angiogenesis. Although there seems promising preclinical and clinical evidence paving way for novel diagnostic and therapeutic interventions, the implicit role of angiogenesis in metastatic head and neck cancers needs further substantiation.

Primary tuberculosis clinically presenting as gingival enlargement: a case report.

Tuberculosis is a chronic systemic granulomatous disease which rarely affects the oral cavity. Oral lesions can be either primary or secondary to systemic tuberculosis, the former being rare. This is a never-before reported case of primary tuberculosis presenting as a localized diffuse gingival enlargement in an 11-year-old Indian female patient. The diagnosis was reached through identification of positive histopathological features, Tuberculin test results, presence of anti-tubercular antibodies confirmed by a polymerase chain reaction. In view of the recent increase in the incidence of tuberculosis and the prevalence of the same, it is reasonable to include tuberculosis in the differential diagnosis of gingival enlargements. This is essential to avoid any serious complications for both the clinician and patient due to a delay in the diagnosis of such a rare but plausible oral condition.

Peri-implant papilla reconstruction: realities and limitations.

In recent years, esthetic demands in dentistry have been climbing ever higher, driven by an enhanced awareness of beauty and physical appearance. Because gingival esthetics has become an important factor in the overall success of most implant-supported restorations, the loss of the peri-implant papilla leads to an esthetic handicap known as black hole disease. Today, one of the most challenging aspects of periodontal reconstructive surgery is to obtain a predictable peri-implant papilla in the esthetic zone. Starting with the facts about the morphology of the peri-implant tissues, to the various parameters influencing papilla reconstruction around implants, this article gives a brief overview of various papilla preservation and reconstruction techniques around implants.

Plasma cell granuloma of gingiva.

An exceedingly rare case of gingival plasma cell granuloma is reported in a 40-year old female patient. The case presented as an exophytic mass of gingiva, clinically resembling traumatic fibroma. Histopathologic findings revealed dense sheets of plasma cells infiltrate. Immunohistochemistry for kappa and lambda light chains showed polyclonal (benign) staining pattern confirming a diagnosis of plasma cell granuloma. It is important to recognise this peculiar lesion because of its highly unusual incidence in involving the periodontium. Clinical features are usually suggestive of traumatic fibroma (benign) but histopathologicaly in early stages it closely resembles plasmacytoma (malignant). This case highlights the need to biopsy unusual lesions to rule out potential neoplasms and also emphasizes the need to submit all the excised tissue for histological examination regardless of clinical impression and/or perceived surgical success. Only by such practice can rare lesion of this type be diagnosed and their incidence studied.