ABSTRACT
BACKGROUND: Salivary constituents have a wide range of functions including oral calcium homeostasis. Salivary proteins such as statherin inhibit crystal growth of calcium phosphate in supersaturated solutions and interact with several oral bacteria to adsorb on hydroxyapatite. Concurrently, saliva, which is supersaturated with respect to calcium phosphates, is the driving force for plaque mineralization and formation of calculus. Thus, the aim of the present study was to estimate and correlate salivary statherin and calcium concentration to the dental calculus formation. METHODS: A cross-sectional study was conducted to assess the relationship between salivary statherin, calcium, and dental calculus among 70 subjects, aged 20-55 years. Subjects were divided into 3 groups based on the calculus scores as interpreted by Calculus Index which was followed by collection of whole saliva using Superâ¢SAL™. Salivary calcium levels were assessed by calorimetric method using Calcium Assay kit (Cayman Chemical, Michigan, USA) and statherin levels by using ELISA Kit (Cusabio Biotech). RESULTS: Statherin levels showed a weak negative correlation with the calcium levels and with calculus formation. The mean salivary statherin and calcium concentration were found to be 0.96 µg/ml and 3.87 mg/ml, respectively. Salivary statherin levels differed significantly among the three groups (p < 0.05). CONCLUSIONS: Our preliminary data indicates that statherin could possibly play a role in the formation of dental calculus.
ABSTRACT
A micelle-vesicle transition induced by n-octanol C(8)OH was observed in an aqueous cetyltrimethylammonium bromide (CTAB)/potassium bromide (KBr) system. This transition was investigated by viscosity, rheology, dynamic light scattering (DLS), and direct imaging technique, cryo-transmission electron microscopy (cryo-TEM). Viscometry shows that the system underwent several morphological transitions with the increase in concentration of C(8)OH (regions I-IV). At low octanol concentration (region I), DLS analysis showed an increase in the apparent hydrodynamic diameter of the micelles with the addition of C(8)OH which was supported by cryo-TEM and rheology. With further addition of C(8)OH, transition of the elongated micelles occurred to a viscoelastic fluid comprising entangled wormlike micelles (region II), for which rheological data can be described by the Maxwell model. Further, the wormlike micelles transform to vesicles at [C(8)OH] ≈ 0.020 M (region III). This transition and the consequent changes in the fluid response can be explained in terms of vesicle formation caused by further addition of C(8)OH. Beyond this concentration (region IV), vesicles are the predominant microstructures in the system which shows unusual temperature response.
