Quality-by-design based development of fast dispersible nimodipine tablets: Formulation attributes and release kinetic assessment.

In the present study fast dispersible nimodipine tablets were developed by direct compression method using quality by design (QbD) approach as per the central composite design by selecting avicel PH 102 (X1) and crospovidone (X2) as independent variables while % friability (R1), disintegration (R2) and hardness (R3) as output variables. Powder blends were assessed for flow characterization. At post compressional stage, several quality assessments were carried out. Particles morphology was observed using scanning electron microscopy (SEM). The stability study on the drug and optimized formulation were determined using thermal gravimetric analysis (TGA) and differential thermal analysis (DTA). RSM plots expressed the interaction of avicel PH 102 and crospovidone to determine the adequate quantities of excipients for the optimized formulation. Polynomial equations were used to validate the experimental design. The optimized formulations were evaluated for friability, disintegration and hardness. Results indicated that formulation (F4) containing avicel PH 102 (35%) and crospovidone (5%) was selected as best optimized formulation having friability 0.59%, disintegration 9 sec, % dissolution 95.703% and hardness 4.14 kg. Results of kinetics models indicated that all the developed formulations followed weibull model.

Gene expression analysis of toll like receptor 2 and 4, Dectin-1, Osteopontin and inflammatory cytokines in human dental pulp ex-vivo.

BACKGROUND: Toll like receptors (TLR) 2 and 4 present on innate immune cells of the dental pulp detect cariogenic bacteria. Along with bacteria, C. albicans may also be present in dental caries. The presence of C. albicans can be detected by Dectin-1 a C type Lectin receptor. Expression of Dectin-1 in human pulpits has not been reported. Similarly, cytokines are released as a consequence of dental pulp inflammation caused by cariogenic bacteria. The T helper (Th) 1 inflammatory response leads to exacerbation of inflammation and its relationship with Osteopontin (OPN) is not known in pulp inflammation. OBJECTIVE: The aim of this study was to observe the expression of Dectin-1, TLR-2, OPN and pro-inflammatory cytokines in irreversibly inflamed human dental pulp and to observe relationship between Dectin-1/TLR-2 and OPN/Pro-inflammatory cytokines in the presence of appropriate controls. METHODS: A total of 28 subjects diagnosed with irreversible pulpitis were included in this ex-vivo study. Fifteen samples were subjected to standard hematoxylin and Eosin (H&E) and immunohistochemistry staining. Whereas, gene expression analysis was performed on 13 samples to observe mRNA expression of pro-inflammatory cytokines; tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (ß), IL-6 Dectin-1, OPN, TLR-2 and TLR-4. SPSS version 21 was used for statistical analysis. One way analysis of variance (ANOVA), Pearson correlation and Chi-square test were used at p ≤ 0.05. RESULTS: Gene expressions of Dectin-1, TLR-2 and TLR-4 were observed in all samples. Dectin-1 and TLR-2 expressions were significantly correlated (r = 0.5587, p = 0.0002). Similarly, OPN and TNF-α expression showed a significant correlation (r = 0.5860, p = 0001). The agreement between histologic and clinical diagnosis was 69.2% in the cases of irreversible pulpitis. CONCLUSION: Dectin-1 was expressed by inflamed human dental pulp. Dectin-1 and TLR-2 expression pattern was suggestive of a collaborative receptor response in inflamed pulp environment. OPN and TNF-α expressions showed a positive correlation indicating a possible relationship.

Comparison of gingival biotype in smokeless tobacco users (Gutka and Paan) and non-tobacco users.

OBJECTIVE: To assess the gingival biotypes in smokeless tobacco (Gutka and Paan) users and compare it with non-tobacco users in Karachi sub-population using trans-gingival probing method (TRAN). METHODS: This in-vivo, cross sectional study was conducted in the department of Operative Dentistry from 20th February 2019 to 25th June 2019 Dow University of Health Sciences, Karachi after obtaining ethical approval from the Institutional review board of DUHS (Ref: IRB-1207/DUHS/Approval/2019/21). A total of 70 participants, 35 subjects currently using smokeless tobacco (Gutka and Paan) and 35 non-tobacco users from both genders were included in the study after taking informed consent. Gingival biotype was recorded using probe transparency method. Probing of the gingival sulcus was performed at the mid-buccal aspect of both maxillary incisors. Depending on the visibility of the underlying probe gingiva was categorized as thin or thick. RESULTS: Statistically significant differences in gingival biotype was observed of both groups (p=0.005). Males were recorded with a higher percentage of thick gingiva in both groups (81% in smokeless tobacco and 65% in non-tobacco) while in females thick gingiva was more prevalent in smokeless tobacco group (85.7%) whereas thin gingiva was noted in non-tobacco group (66.7%); although the results between genders was statistically insignificant. The comparison between different age groups, genders and both groups was statistically insignificant. CONCLUSIONS: Significant difference was observed between gingival biotype of smokeless tobacco and non-tobacco user groups. No statistically significant results were observed between genders and age groups.