Journal of Research in Dental and Maxillofacial Sciences
Volume:3 Issue: 1, Winter 2018

Lichen planus (LP) is a chronic inflammatory disease with an uncertain pathogenicity. Recent reports have revealed that angiogenesis is effective in the pathogenesis and biologic behavior of lesions. Considering the limitations of the studies related to angiogenesis in oral LP (OLP) and the controversial results, the present study aimed to compare the expression of vascular endothelial growth factor (VEGF) in OLP and normal mucosa. In this case-control study, 4-µm sections were prepared from selected OLP (erosive type) blocks and normal mucosa samples for immunohistochemistry (IHC) staining with VEGF marker. VEGF expression was quantitatively assessed via counting the positive-stained cells. The mean percentages of positive-stained cells in each sample were categorized in three groups: score 0 (the presence of 10% or lower), score 1 (the presence of 10% to 50%), and score 2 (the presence of more than 50% of stained cells). T-test and Mann-U-Whitney test were used for statistical analyses. The mean percentage of VEGF expression was 39.8% in 35 OLP samples, and 20.5% in 20 normal mucosa samples. Twenty OLP samples (57%) had score 1, and 15 (43%) had score 2. Eighteen normal mucosa samples (90%) had score 1, and two (10%) had score 2. Also, score 0 was not reported in any of the samples. The percentages of VEGF expression in OLP and normal mucosa did not show any statistically significant differences (P=0.5). However, there was a significant difference between OLP and normal mucosa in VEGF expression score (P=0.012), and OLP samples had significantly higher scores. According to the results, VEGF expression in erosive OLP samples was significantly higher than that in normal mucosa.

Dental caries is one of the most common childhood diseases worldwide. The implementation of strategies that facilitate the prevention of early dental caries and interrupt its progression has been recently advocated. It has been reported that casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) derived from casein reduces tooth demineralization and enhances the remineralization process. The aim of this in-vitro study was to assess the efficacy of two types of CPP-ACP paste in calcium uptake by enamel surfaces. Forty premolars were longitudinally dissected into experimental and control halves, and were coated with nail varnish, except for an enamel window of 4×4 mm. The samples were subjected to cycling in a demineralizing solution and were divided into two groups of GC Tooth Mousse CPP-ACP paste and Misswake CPP-ACP paste. The calcium contents of each half were examined using the acid etch enamel biopsy technique and were measured by atomic absorption. The values were statistically analyzed using Kolmogorov-Smirnov test and one-way analysis of variance (ANOVA). The enamel surfaces treated with the pastes exhibited higher calcium contents compared to the controls. There was a significant difference between GC Tooth Mousse CPP-ACP paste and Misswake CPP-ACP paste in terms of calcium uptake; a higher calcium uptake was witnessed with GC Tooth Mousse CPP-ACP paste than with Misswake CPP-ACP paste (P<0.05). Misswake CPP-ACP paste presented some protective potentials; however, the samples treated with GC Tooth Mousse CPP-ACP paste were better able to uptake calcium. These pastes could be considered as effective means for the prevention of dental caries in susceptible patients.

Oral lichen planus (OLP) is a chronic mucocutaneous inflammatory disease. Although the etiology of this disease is unknown, some factors including stress, antioxidant deficiency, and folic acid deficiency have been claimed to have a role in its incidence. The purpose of this study was to assess and compare the serum folic acid level in OLP patients and healthy subjects. in this case-control study, 52 OLP patients (36 females and 16 males) were selected as the case group, and 48 healthy individuals (36 females and 12 males) were assigned to the control group. The serum folic acid level was measured in the two groups. Data were analyzed using T-test with the level of significance set at 0.05. the mean and standard deviation (SD) of serum folic acid level was equal to 8.74±4.11 ng/ml in the case group and 9.12±3.5 ng/ml in the control group with no statistically significant difference (P=0.12). The results of the present study indicated that the serum folic acid level in OLP patients did not have a significant difference with that in healthy subjects.

Neurosensory disorders after implant insertion are one of the main concerns in implant treatments. Neurosensory disorders can be driven by different factors including the contact of the implant with the nerve, pressure of edema, hematoma, scar, or dental injections. This study aimed at investigating the distance between the implant and the inferior alveolar nerve (IAN) and its impact on neurosensory disorders. In this descriptive study, panoramic radiographs were taken from 100 patients experiencing neurosensory changes after 10 days of implantation. The patients were reassessed 4 weeks later, and the distance (mm) between the implants and the IAN was measured. Data were analyzed using descriptive statistics. All patients experienced neurosensory changes 10 days after implantation. Four weeks after surgery, 82 patients healed: the distance between the implants and the IAN was 1-2 mm in 16 patients and 2 mm in 66 patients. In 18 patients, neurosensory changes persisted; in this group, the distance between the implants and the IAN was less than 1 mm in 11 patients, 1-2 mm in 6 patients, and more than 2 mm in 1 patient. The results indicated that the chance of healing of neurosensory changes is significantly correlated with the distance between the implant and the IAN (P<0.01). This correlation was not significant with respect to age or gender (P<0.9). It seems that the lesser is the distance between the implant and the IAN, the lower is the chance of healing of neurosensory changes.

The most common method of increasing implant stability in the posterior maxilla comprises the reinforcement of bone height using bone grafts in sinus lift surgery. The purpose of the present study was to compare autogenous and allogeneic bone grafts in implant stability after open sinus lift surgery. This split-mouth clinical trial compared the implant stability in 10 patients who needed bilateral open sinus lifts, including 8 men and 2 women. Each side of each patient's jaw was assigned to either case or control groups. Open sinus lift was performed on both sides of the jaw: autogenous bone graft was used on the side considered as the control, while allogeneic bone graft was used on the side assigned to the case group. After four months, the implant stability was evaluated and recorded in each group using the Periotest® system. The mean value related to implant stability was -2.78±2.31 in the control group and -3.19±2.51 in the case group. The values below zero (negative values) indicate an acceptable stability. According to Mann-U-Whitney test, there were no statistically significant differences between the two groups (P>0.05); however, the intragroup analysis using Wilcoxon test showed statistically significant results with regard to implant stability in each group (P<0.05). Based on the results, autogenous and allogeneic bone grafts have similar effects on implant stability after open sinus lift surgery, and both bone grafts provide a suitable implant durability.

Changes in the physical properties of casts retrieved from disinfected impressions are a common problem in the fabrication of dental prostheses. However, there are limited data available about the effect of disinfecting solutions on the surface roughness of casts. This study aimed to assess the surface roughness of casts retrieved from addition silicone impressions disinfected by immersion in three different disinfectants for 5 and 30 minutes. This in-vitro experimental study was conducted on 49 casts in 7 groups (n=7). A standard stainless steel die was used according to ANSI/ADA specification no. 25, and impressions were made using a low-viscosity addition silicone impression material. The impressions were disinfected by immersion in 1% sodium hypochlorite (NaOCl), 2.4% glutaraldehyde, or 5% povidone-iodine for 5 and 30 minutes. All impressions were poured with type IV dental stone, and their surface roughness (Ra) was measured using a digital hand-held roughness tester. Data were analyzed using two-way analysis of variance (ANOVA) and Tukey's test. One-way ANOVA showed a statistically significant difference between the control group and the other 6 groups (P=0.004). 1% NaOCl/5 minutes was the only group which presented a different result from the control group (P=0.012). Two-way ANOVA showed that over time, the surface roughness of casts retrieved from silicone impressions disinfected by immersion in a disinfectant decreased (P=0.002), but no significant difference was noted between the disinfectant agents (P=0.243). The type of the disinfectant had no significant effect on surface roughness, although an increased duration of disinfection decreased the surface roughness of casts.

Hyper-Immunoglobulin M (IgM) syndrome (HIGM) is a rare primary immunodeficiency in which defective B-cell isotype switching results in a phenotype characterized by elevated or normal serum IgM levels and low levels of other Ig classes, leading to an increased susceptibility to infection, neutropenia, autoimmune disorders, and malignancies. In this disease, a mutation occurs in the CD40 gene, leading to combined B-cell and T-cell immunodeficiencies. The oral manifestations include wound-like lesions, oral candidiasis, gingivitis, periodontitis, and enamel defects. Theoretically, systemic conditions affecting ameloblastic activity during enamel mineralization, such as abnormal oxygen levels resulting from hypoventilation in various respiratory diseases, result in enamel defects. We report a 10-year-old male with hyper-IgM immunodeficiency. The patient had suffered from frequent infections, respiratory problems, and bronchopneumonia from the age of 2 years. At 4 years of age, type 1 diabetes mellitus was diagnosed. During dental examinations, enamel defects were found in seven permanent teeth. A meticulous dental evaluation of children with systemic diseases is mandatory in order to discover possible developmental dental defects and to plan early interventions.