Tongue microbiome of smokeless tobacco users

Background

The possibility that smokeless tobacco may contribute to oral carcinogenesis by influencing the oral microbiome has not been explored. This preliminary cross-sectional study sought to assess the effect of using shammah, a form of smokeless tobacco prevalent in Arabia, on the tongue microbiome. Tongue scarping samples were obtained from 29 shammah users (SU; 27.34 ± 6.9 years) and 23 shammah non-users (SNU; 27.7 ± 7.19 years) and analyzed with 16S rRNA gene sequencing (V1-V3). Species-level taxonomy assignment of the high-quality, merged reads was obtained using a previously described BLASTn-based algorithm. Downstream analyses were performed with QIIME, LEfSe, and R.

Results

A total of 178 species, belonging to 62 genera and 8 phyla were identified. Genera Streptococcus, Leptotrichia, Actinomyces, Veillonella, Haemophilus, Prevotella and Neisseria accounted for more than 60% of the average microbiome. There were no differences between the two groups in species richness and alpha-diversity, but PCoA showed significant separation (P = 0.015, ANOSIM). LEfSe analysis identified 22 species to be differentially abundant between the SU and SNU. However, only 7 species maintained a false discovery rate of ≤0.2 and could cluster the two groups separately: Rothia mucilaginosa, Streptococcus sp. oral taxon 66, Actinomyces meyeri, Streptococcus vestibularis Streptococcus sanguinis and a potentially novel Veillonella species in association with SU, and Oribacterium asaccharolyticum with SNU.

Conclusion

These preliminary results indicate that shammah use induces tongue microbiome changes including enrichment of several species with high acetaldehyde production potential, which warrants further investigation.

Oral health status and treatment needs among school children in Sana'a City, Yemen

Data on the oral health status and treatment needs among Yemeni children are lacking.

OBJECTIVES

To assess caries prevalence, treatment needs and gingival health status among school children in Sana'a City and to examine how these are affected by age, gender and khat chewing.

METHODS

1489 children (6- to 14-year old) were randomly selected from 27 schools representing all nine districts of Sana'a City. Dental caries and treatment needs were evaluated using standard WHO oral survey methods. The plaque index (PI), calculus index (CI) and the gingival index (GI), recorded at the six Ramfjord's teeth, were used to assess gingival health status.

RESULTS

4.1% of the study subjects were caries-free. Prevalence of these was significantly higher among the males. Overall, mean dmfs, dmft, DMFS and DMFT scores were 8.45, 4.16, 3.59 and 2.25 respectively. The decayed component accounted for >85% of the scores. The highest dmfs/dmft means were found among the 6-8 years age group, while the highest DMFS/DMFT means were scored by the 12-14 years age group. The need for restorative treatment and extractions was high; the former was significantly higher among the females. All subjects had gingivitis; the mean PI, CI and GI were 1.25, 0.3 and 1.36 respectively. Khat chewing did not affect caries experience; however, it was significantly associated with higher PI, CI and GI scores.

CONCLUSIONS

The prevalence of caries, gingivitis and treatment needs among children in Sana'a city is high. More surveys in other Yemeni cities to generate comprehensive data are required.

Khat (Catha Edulis Forsk) induced apoptosis and cytotoxicity in cultured cells: A scoping review

BACKGROUND

Khat (Catha edulis Forsk) leaves are chewed by people in certain regions of East Africa and the Middle East for their stimulating amphetamine-like effects. The purpose of this scoping review is to systematically map the current in vitro publications that investigated the toxicological potential effects of khat on cultured human or animal cells in terms of cellular viability and activity.

METHODS

A comprehensive electronic database search was undertaken up to December 2020 without starting date or language restrictions in accordance with the PRISMA extension for scoping review guideline and methodological quality evaluation based on the guidelines for reporting pre-clinical in vitro studies on dental materials. All in vitro studies that investigated the effect of khat plant extract (Catha Edulis) on the cultured human or animal cells were included.

RESULTS

The initial search yielded 599 articles and 16 articles were finally selected to be included. The treatment of cells with khat produced different degrees of cellular changes, including decreased cellular survival, induction of apoptosis, increased ROS production, alteration of cell phenotype, and of arrest cell cycle. In this contest, khat-exposed cells expressed higher levels of pro-apoptotic protein Bax and lower levels of anti-apoptotic Bcl-2, up-regulated p38, p53, p16, and p21 proteins, as well as premature expression of differentiation markers.

CONCLUSION

Based on the current scoping review, khat induced apoptosis and cytotoxicity in cultured human cells, including oral cells.

Salivary parameters among Arabian snuff (Shammah) users

OBJECTIVES

To evaluate the salivary flow rate (SFR),  pH, and buffer capacity (BC) among healthy shammah users (SU) in comparison with healthy non-shammah users (NSU). Methods: This case-control study was conducted at the College of Dentistry, Jazan University, Jazan, Kingdom of Saudi Arabia between March 2016 and May 2017. A sample of 27 SU and 30 NSU were recruited. Unstimulated saliva was collected and SFR, pH, and BC were determined. Dental health was assessed using the decay-missing-filled teeth (DMFT) index.  Results: Shammah users were slightly older than NSU (28.9±6.9 versus 24.9±4.3 years). Salivary flow rate  was not significantly different, but pH (6.68±0.46) and BC (5.7±2.07) were significantly lower in SU users than in NSU (7±0.37; p=0.002 versus 8.1±1.47; p less than 0.001). Conversely, the DMFT in SU users was significantly higher (7.96±5.17) compared to that of NSU (4.53±3.46; p=0.007). Salivary pH and BC were significantly and directly correlated (rs= 0.576). The former was significantly and directly correlated with SFR (rs= 0.404), but the latter was not. In contrast, BC inversely correlated with decay (rs= -0.385) and DMFT (rs= -0.399). Conclusions: Shammah use is associated with alterations in saliva quality (pH and BC). It is also associated with poor dental health either through a direct effect or mediation by altered salivary parameters.

In-vitro Evaluation of Wild Bitter Melon (Momordica charantia) Extracts against Periodontopathic Bacteria (Prevotella intermedia and Porphyromonas gingivalis) using Antibacterial, Anti-Inflammatory and Molecular Docking Analysis

Wild bitter melon (Momordica charantia) extracts were prepared and their antibacterial and anti-biofilm assay were investigated against two different periodontopathic bacteria (Prevotella intermedia and Porphyromonas gingivalis) for the first time to the best of our knowledge based on the presence of different phytochemical compounds. Momordica charantia solvent extracts were prepared and phytochemical analysis was performed. Minimal inhibitory and bactericidal concentrations were determined. Antibacterial activity was evaluated using the standard well diffusion method. Anti-inflammatory studies on periodontal ligament (PDL) cell viability and lipopolysaccharide (LPS)-induced inflammation were performed. Molecular docking was investigated between the bioactive compound (Charantadiol A) of plant extract and biofilm-expressing genes in each test organism. Phytochemicals from ethanol extract showed promising results; alkaloids, flavonoids, phenols, and tannins were found present at considerable levels. The minimum inhibitory concentration was found to be 400 μg/mL for Prevotella intermedia and Porphyromonas gingivalis. Antibacterial activity expressed in terms of zone of inhibition showed 14 mm to 18 mm zones against the test organisms. The molecular docking report revealed the maximum binding energy of about -6.54 Kcal/Mol of binding energy between Charantadiol A and fimA of Porphyromonas gingivalis. Anti-biofilm study showed that the minimum biofilm eradication concentration (MBEC) of Momordica charantia expressed significantly good results against the test organisms. The PDL cell viability values expressed in percentage indicated the anti-inflammatory properties of Momordica charantia extracts at three different known concentrations. The findings concluded that Momordica charantia extracts have promising prospects as an anti-periodontopathic and anti-inflammatory agent.

Performance of Dental Students and Interns in the Motivation and Verbal Delivery of Oral Hygiene Instructions in Dental Practice

AIM

The aim of this survey was to evaluate the ability of dental students and interns to deliver oral hygiene instructions.

MATERIALS AND METHODS

This survey targeted patients aged 17-67 years who sought different dental treatments performed by final (sixth)-year dental students or dental interns. Both patients and therapists participated in filling out the questionnaire. The questionnaire included an exploration of the ability of therapists to prescribe dental hygiene aids commonly used in oral hygiene dentistry.

RESULTS

In total, 150 patients and 150 therapists of both genders participated in this survey. The results showed that 47.3% of all therapists taught the patients the brushing technique; however, only 20% of the therapists reinforced oral hygiene instructions. Similarly, only 26% of therapists instructed their patients to renew their toothbrushes regularly, and 34% of the therapists instructed the patients on using dental floss. Only 32% of therapists prescribed a mouthwash to their patients, and 40.7% of the therapists used a disclosing agent. The difference was highly significant between students and interns in all the above activities, in favor of the dental students.

CONCLUSION

The result shows a low level of therapist's performance, both students and interns, in delivering oral hygiene instructions to their patients.

CLINICAL SIGNIFICANCE

Dental students and interns take a big responsibility in motivation and delivery of oral hygiene instructions in dental clinics to their patients. Evaluating the performance of students and interns in delivering oral health instructions in dental clinics will facilitate establish oral health programs to improve the performance of therapists in motivation and delivering the oral hygiene instructions and therefore increase the ability of patients to respond.

WhatsApp-assisted Oral Health Education and Motivation: A Preliminary Randomized Clinical Trial

AIM

The study aimed to assess the efficacy of using WhatsApp instant messages in enhancing the oral hygiene in patients with gingivitis.

MATERIALS AND METHODS

Forty-three systemically healthy male dental patients with gingivitis were recruited consecutively and randomly divided into two groups: WhatsApp group (n = 24) and a control group (n = 19). At baseline visit, the participants were educated and motivated about oral health and given a folio on instructions about the oral hygiene preventive measures. The participants in the study group further received WhatsApp messages about the dental care at weekly intervals throughout the study (3 months). Plaque index (PI) and gingival index (GI) were measured at baseline and after 1 and 3 months.

RESULTS

The averages of PI and GI were not significantly different between both groups at any time point of measurement (baseline, after one, and three months; p value >0.05). Intragroup comparisons revealed that the reductions in PI were highly significant after 1 and 3 months (-0.26 ± 0.26 and -0.57 ± 0.35, respectively, for WhatsApp group, and -0.24 ± 0.27 and -0.64 ± 0.4. respectively, for the control group; p value range: 0.001 to <0.001). Similar were the reductions in GI in each individual group (-0.17 ± 0.46 and -0.67 ± 0.05, respectively, for WhatsApp group, and -0.28 ± 0.29 and -0.69 ± 0.41, respectively, for the control group: p value < 0.001).

CONCLUSION

Implementing WhatsApp instant messages does not appear to add extrabenefit to the traditional motivation and education on oral hygiene practices in terms of changes in PI and GI over time in patients with gingivitis.

CLINICAL SIGNIFICANCE

Although the results were not motivating, this does not preclude the dental professionals from using WhatsApp and the similar technology to deliver oral healthcare advices.