Effect of oral irrigation device and its solution type on the surface roughness and topography of Bulk-fill composite resins

Background

Surface roughness and topography of composite resin materials have a significant role in biofilm aggregation, periodontitis, and recurrent caries. The present study evaluated the effect of the Waterpik oral irrigation device (OID) with different solution [water/ chlorhexidine (CHX)] on the surface roughness and topography of microhybrid (x-tra fil) and nanohybrid (Tetric N-Ceram Bulk) bulk-fill composite resins.

Material and Methods

Disk-shaped samples were prepared from each composite resin, measuring 5 mm in diameter and 3 mm in height, and assigned to three groups in terms of treatment (n=19): group A, control (storage in distilled water); group B, OID with water; group C, OID with 0.5% CHX. The samples were treated for eight weeks, simulating one-year use of OID. Profilometry and scanning electron microscopy (SEM) were used to evaluate and compare quantitatively surface roughness (Ra) and qualitative topography of composite resin surfaces before and after treatment. The data were analyzed with paired-samples, Wilcoxon, and generalized estimating equations tests (α=0.05).

Results

The application of OID increased the Ra of composite resin compared to the control group (P<0.001). No significant difference was detected between the two solutions (water and CHX) (P=0.615). The effect of composite resin type and the cumulative effect of composite resin type and OID solution were not significant on the surface roughness changes of the samples (P=0.243 and P=0.464, respectively).

Conclusions

OID with water and CHX solutions increased the surface roughness and topographic changes of microhybrid and nanohybrid bulk-fill composite resins.

Key words:Composite resins, irrigation, mouthrinse, surface roughness, topography.

Mannose-binding Lectin Deficiency in Patients with a History of Recurrent Infections

Mannose-binding lectin (MBL) is a protein of innate immune system that is involved in opsonization and complement activation. MBL deficiency is associated with predisposition to infectious diseases; however subnormal levels are also seen in healthy subjects. The aim of this study was to investigate the prevalence and clinical manifestation of MBL deficiency in patients with increased susceptibility to infection. We studied the MBL serum concentration of 104 patients with a history of recurrent and/or severe infections referred to Immunology, Asthma and Allergy Research Institute (IAARI) in order to evaluate the primary immunodeficiency (PID). The distribution of MBL deficiency in these patients and 593 healthy subjects of previous study were analyzed. The frequency of individuals with MBL deficiency was significantly higher in patients with recurrent and/or severe infections (13.5% [14/104]) compared with healthy subjects (4.7% [28/593]; p=0.001; OR 3.1, 95% CI 1.5-6.1). However, in 10.9% (7/64) of patients with recurrent infections without any immunodeficiency background, the MBL deficiency was detected. On the whole, our findings indicate an association between MBL deficiency and increased susceptibility to infections.

Mannan-binding lectin serum levels in 593 healthy Iranian children and adults

Mannan-binding lectin (MBL) is a vital protein of innate immune system and has two critical functions: complement activation through the lectin pathway and opsonization. MBL deficiency has been classified as the most common inherited immunodeficiency known in humans (about 30% of the population), and is associated with predisposition to infections and high risk of some autoimmune diseases. The purpose of this study was to determine the profile of MBL serum level in Iranian healthy population in association with sex and age groups for the first time. We studied the serum concentration of MBL in 593 Iranian healthy cases: 340 males and 235 females in 4 different age groups by using enzyme-linked immunosorbent assay. The mean serum levels of MBL were 3.854 ± 2.77 µg/ml at the age of less than 6 months, 4.147 ± 3.54 µg/ml at 6 months to 2 years of age, 4.410 ± 3.09 µg/ml at 2-6 years and 2.207 ± 1.73 µg/ml in adults. There was significant differences in the mean concentration of MBL among different age groups of children and also between children and adults (p<0.05). No association was observed between sex and MBL concentrations. MBL serum levels of Iranian population seem to be different from some of other populations which may be explained by genetic variations. The MBL values in this study can be used as a normal reference range for future studies in Iranian population.