Journal of

Background and aim: Oral lichen planus, is a chronic inflammatory mucocutanous lesion which is defined as a premalignant lesion. Matrix metaloprotenase 2 (MMP-2) and MMP-9 are protenases which facilitates invasion of tumoral cells to connective tissue and are over-expressed in premalignant and malignant lesions. The aim of this study was to determine the expression of MMP-2 in erosive and non-erosive oral lichen planus and inflammatory hyperplasia by immunohistochemistry.
Methods: in this cross sectional study 39 specimens of non-erosive oral lichen planus (with and without dysplasia), 36 specimens of erosive ones (11 dysplastic and 25 non-dysplastic, 32 inflammatory hyperplasias and 6 samples of normal oral mucosa were chosen form pathology archive of Faculty of Dentistry, Mashhad university of Medical Sciences and were stained immunohistochemically by MMP-2 and MMP-9 markers. Kruskal-Wallis, Mann-Whitney and Spearman correlation coefficient were used.
Results: The highest mean expression of MMP-2 and MMP-9 (in all layers) were observed in erosive oral lichen planus (68.18±31.62 and 94.5±3.5, respectively). MMP-9 expression in erosive oral lichen planus in comparison to non-erosive one showed significant difference in all layers (P<0.001) and the expression of MMP-2 showed a significant difference in basal –para basal and prickle layers (respectively: P=0.008, P<0.001).
Conclusion: the linear increase seen in the expression of markers from normal mucosa to erosive oral lichen planus indicates the difference of biological behavior between erosive and non-erosive oral lichen planus. Hence, it is concluded that erosive oral lichen planus is of the higher premalignan potential compared with its non-erosive correspondent.

Background and Aim: Lichen planus (LP) is a cutaneous disease characterized by violaceus flat topped papules in variable size. It may involve body surface areas such as mocus membranes. Some studies have reported an association between oral LP ad diabetes mellitus. The aim of this study was to compare the frequency of diabetes mellitus between patients with and individuals without LP.
Methods: A case-control study was done on 30 patients suffering oral LP as case group and 60 healthy individuals as control group. Diagnosis of oral LP was confirmed by typical clinical and histopathologic findings. Participants in control group were selected from general population after matching for sex and age. Venipuncture was done to take 5 ml blood sample for measuring fasting serum blood glucose levels in both groups. A repeated blood sampling was done for ones with abnormal results in the first sampling. Findings of the study were analyzed using SPSS 16.0 statistical software.
Results: Thirty LP patients [man 13 (43.3%), woman 17 (56.7%)] with mean age (mean±stabdard deviation) of 46±13.7 years and 60 healthy individuals [man 26(43.3%), woman 34 (56.7%)] with mean ages of 46±14 years were recruited to this study. In case group only one person (3.3%) suffered from diabetes mellitus, but none of healthy group had fasting blood sugar above the normal value. In quantative evaluation, mean level of fasting blood sufar was 102.5±33 mg/dL in case group and 111.1±49.3 mg/dLin control group (P=0.09).

Background and Aim: Oral lichen planus is a chronic
muco-cutaneous immunopathological disorder that commonly affects the oral mucosa. Candida albicans is the most common pathogen associated with oral candidiasis. The aim of this study was to determine the effect of 810 nm low power laser wavelength as an adjuvant in the treatment of
nystatin-resistant C.albicans in patients with oral lichen planus.
 

Methods: In this experimental study, 5 nystatin-resistant C.albicans were isolated from the oral cavity of patients with ulcerative lichen planus. Drug susceptibility testing was performed based on CLSI-M27-A3 and showed that these isolates were resistant to nystatin. The fungal suspension with a dilution of 0.5 McFarland was exposed to a diode laser with a wavelength of 810 nm and a density energy of 20.38 j / cm2 with a time of 20 seconds. Then the results of minimum inhibitory concentration (MIC) were recorded for each group.
 

Results: 810 nm laser caused a significant reduction in nystatin-resistant C.albicans colonies (P<0.001). The MIC did not decrease significantly after the exposure.
 

Conclusion: Laser irradiation reduces the number of nystatin-resistant C.albicans colonies. But this effect does not necessarily change the MIC. Dentists should be aware that in cases of resistant Candida strains, a low-power diode laser with a wavelength of 810 nm can play a role in reducing colonies and responding better to standard treatment.