From Short Circuit to Completed Circuit: Conductive Hydrogel Facilitating Oral Wound Healing

The primary challenges posed by oral mucosal diseases are their high incidence and the difficulty in managing symptoms. Inspired by the ability of bioelectricity to activate cells, accelerate metabolism, and enhance immunity, a conductive polyacrylamide/sodium alginate crosslinked hydrogel composite containing reduced graphene oxide (PAA-SA@rGO) is developed. This composite possesses antibacterial, anti-inflammatory, and antioxidant properties, serving as a bridge to turn the "short circuit" of the injured site into a "completed circuit," thereby prompting fibroblasts in proximity to the wound site to secrete growth factors and expedite tissue regeneration. Simultaneously, the PAA-SA@rGO hydrogel effectively seals wounds to form a barrier, exhibits antibacterial and anti-inflammatory properties, and prevents foreign bacterial invasion. As the electric field of the wound is rebuilt and repaired by the PAA-SA@rGO hydrogel, a 5 × 5 mm2 wound in the full-thickness buccal mucosa of rats can be expeditiously mended within mere 7 days. The theoretical calculations indicate that the PAA-SA@rGO hydrogel can aggregate and express SOX2, PITX1, and PITX2 at the wound site, which has a promoting effect on rapid wound healing. Importantly, this PAA-SA@rGO hydrogel has a fast curative effect and only needs to be applied for the first three days, which significantly improves patient satisfaction during treatment.

Lichenoid lesions of the upper labial mucosa: a systematic review and a report of a new case with extensive follow-up

OBJECTIVES

The paper reports the demographic characteristics of patients with lichenoid lesions affecting only the upper labial mucosa, with or without associated lesions in the maxillary anterior gingiva, alongside the lesions' clinical and histopathological features, treatment, follow-up and prognosis. Also, a new case with lengthy follow-up is presented.

MATERIALS AND METHODS

A systematic review was performed in line with PRISMA guidelines. The literature search sources were PubMed, Scopus and Web of Science.

RESULTS

In all, 26 patients (21 women, 5 men) were included in the review. 80.8% (n = 21) of the labial lesions were clinically erythematous and 19.2% (n = 5) were accompanied by white striations. The gingiva was affected in 46.2% of cases. All patients (100%, n = 24) reported symptoms. All of the lesions presented histological features of lichenoid inflammation. Granulomas were noted in 65.4% (n = 17) of the lesions. Topical corticosteroid was the most frequent therapy (89.5%, n = 17).

CONCLUSIONS

Lichenoid lesions found solely in the upper labial mucosa, with or without adjacent gingival lesions, are rarely reported in the literature, and the reporting is often incomplete. A definitive aetiology could not be established for the lesions. Likewise, there is little information about this condition's long-term prognosis.

Antioxidant therapy for patients with oral lichen planus: A systematic review and meta-analysis

Aims: This study aimed to systematically review the efficacy and safety of antioxidants for patients with Oral lichen planus (OLP). Methods: Databases, including PubMed, Web of Science, Cochrane Library, Embase, and Google Scholar, were searched up to 30 April 2022, for randomized controlled trials on the antioxidant therapy of OLP. The following endpoints were analyzed: pain score, clinical score, pain resolution rate, clinical resolution rate, and adverse effects. Results: A total of 19 studies met the inclusion criteria, and 17 studies with 704 patients were included in the meta-analysis. The findings showed that antioxidant therapy could significantly reduce the pain score [standardized mean difference -0.72 (-1.36, -0.07), P = 0.03, I2 = 87%, PI2 < 0.00001] and clinical score [SMD -2.06 (-3.06, -1.06), P < 0.0001, I2 = 94%, PI2 < 0.00001] of patients with OLP and improve the pain resolution rate [risk ratio (RR) 1.15 (1.01, 1.31), P = 0.04, I2 = 45%, PI2 = 0.09] and clinical resolution rate [RR 1.40 (1.10, 1.78), P = 0.006, I2 = 72%, PI2 = 0.002]. Conclusion: The study demonstrated that antioxidant therapy was beneficial for patients with OLP, and antioxidants might be used to treat OLP. Systematic Review Registration: https://clinicaltrials.gov/, identifier CRD4202233715.

Problem-based learning and case-based learning in dental education

Background

Numerous novel teaching methods have been developed in recent times for use in medical education. Of these methods, problem-based learning (PBL) and case-based learning (CBL) have attracted the most attention. We evaluated and compared the efficiency of these two teaching methods in dental education and discussed the importance of teachers to these courses. This study aims to evaluate the efficiency of PBL and CBL in dental education, and discuss the importance of teachers to the courses.

Methods

In this study, 28 students enrolled in a seven-year program at the College of Stomatology at Shanghai Jiao Tong University were chosen as participants. In the fourth year, PBL combined with independent learning was used to teach students the theory of oral mucosal diseases. During the internship, CBL was used to present specific cases. Both methods were carried out with group discussion. After the PBL course, teachers assessed its effect by the students’ class performance, their ability to collect data, and group cooperation. After the CBL course, its effect was assessed by the students’ ability in history-taking, diagnosis and antidiastole, and case analysis. In addition, the teachers’ roles in both methods were assessed by both the students and the teachers themselves. Data was collected by questionnaire survey and statistically analyzed with SPSS Statistics 20.

Results

PBL significantly improved students’ self-learning abilities in the theory course. CBL helped students make diagnoses and develop treatment plans for actual cases in the internship. Both students and teachers thought that teachers were indispensable to both PBL and CBL. There was no difference between student and teacher views.

Conclusions

Although PBL and CBL have different focuses, their combination may enhance teaching effectiveness in dental education. Additionally, teachers play an important role in the application of both these teaching methods.

Therapeutic effect of curcumin on oral diseases: A literature review

Curcumin (diferuloylmethane) is a polyphenol compound extracted from the rhizome of the plant Curcuma longa. It has the feature of being a yellow or orange pigment with a variety of biological properties, including anti-inflammation, antioxidation, anti-tumor, anti-bacteria, anti-fungus, and wound healing. Previous studies have reported the role of curcumin in treating different inflammatory diseases and tumors in vitro and in vivo. Recently, it has been demonstrated that curcumin has therapeutic benefits in oral mucosal diseases, periodontal diseases, and mouth neoplasms. In this review, we will focus on the therapeutic effects of curcumin on oral diseases.

Relationship between the immunohistological examination and fluorescence visualization of oral squamous cell carcinoma

Disorders of the oral mucosa are considered easy to diagnose since they can be visualized and examined directly. A change in the color of the oral mucosa reflects histopathological changes and is an important diagnostic parameter. However, the subjective perception of color varies. To determine the extent of resection for oral mucosa conditions, it is necessary to digitize the color and perform objective assessments. In recent years, fluorescence visualization devices and analysis software that measure tissue luminance G have been employed for the identification of oral mucosa diseases. Fluorescence visualization is presumably based on the decrease in epithelial flavin adenine dinucleotide content and luminance G values due to the destruction of collagen cross-links [fluorescence visualization loss (FVL)]. However, cases with differences between luminance values and histopathological presentation exist. Therefore, additional factors may affect fluorescence visualization. The present study used a portable, non-contact oral mucosa fluorescence visualization device for luminance measurements in seven patients with oral squamous cell carcinoma. Furthermore, Picro-Sirius Red and immunohistochemical staining were performed for CK13, CK17, Ki67, p53 and E-cadherin in the FVL(+) (lesion) and FVL(−) (resection stump) areas to elucidate the principle of fluorescence visualization. Fluorescence was significantly lower in the FVL(+) than in the FVL(−) areas, and the mean luminance G value was 56. The Picro-Sirius Red stain revealed collagen destruction in the FVL(+) areas but no collagen disruption in the FVL(−) areas. CK13 was negative in the FVL(+) and positive in the FVL(−) areas, whereas the opposite pattern was observed for CK17. In the FVL(+) area, p53 staining was positive. E-cadherin expression was enhanced in the FVL(−) areas and reduced in the FVL(+) areas. Furthermore, the luminance G value tended to be lower in cases with weaker E-cadherin staining. The aforementioned results suggest that decreased E-cadherin expression may be a factor that regulates fluorescence visualization.

Intraoral human herpes viruses detectable by PCR in majority of patients

OBJECTIVES

To identify factors which influence the intraoral prevalence of human herpes viruses (HHVs) using mucosal swabs, saliva samples and qPCR analysis.

METHODOLOGY

In this cross-sectional observational study, matched saliva and oral swabs were collected from a total of 115 subjects: 70 immunocompetent subjects with no mucosal abnormalities, 22 with mucosal abnormalities and 23 therapeutically immunocompromised individuals. Extracted DNA was analysed by multiplex qPCR for detection and quantification of HHVs 1-6.

RESULTS

At least one human herpes virus was detected in 77.1% of immunocompetent individuals with no mucosal abnormalities, with EBV the most commonly detected at 61.4%. HHV-6 was detected in 17.1%, HSV-1 in 4.3% and CMV in 1.1%. Detection was higher in saliva than in oral swabs. There was no detection of HSV-2 or VZV. Neither presence of oral mucosal abnormality nor therapeutic immunocompromise was related to increased detection of human herpes virus.

CONCLUSION

Commensal detection rates of EBV are high, and caution in clinical correlation of positive detection is warranted. Commensal CMV rates are low, and detection is likely to be clinically relevant. This study presents a comprehensive commensal detection rate of HHVs 1-6 by qPCR in saliva and swabs.

Prevalence of Oral Mucosal Diseases in Older Adults in Mainland China: A Meta-Analysis of Observational Studies

Oral mucosal disease (OMD) is a public health challenge globally, but the epidemiological findings in older adults have been inconsistent in China. Thus, this meta-analysis was carried out to explore the prevalence of OMD and its moderating factors in this population. An electronic literature search was conducted of both international (PubMed, PsycINFO, and EMBASE) and Chinese (China National Knowledge Infrastructure and WanFang) databases from inception to November 1, 2019. The Der-Simonian and Laird random effects model was used to synthesize the prevalence of OMD and its 95% confidence intervals (95% CI). Twenty-four studies covering 23,653 older adults were included. The pooled prevalence of OMD was 23% (95% confidence interval: 17.9%-29.0%) Subgroup analyses and meta-analysis revealed that the prevalence of OMD was significantly associated with the reporting sampling, year of publication, and survey (all p values <0.05). This meta-analysis found that the prevalence of OMD among older adults in mainland China was significantly high. Early detection and effective intervention of OMD in older adults have public health and clinical importance.

[Epidemiological investigation of chewing fresh or dried betel nut and oral mucosal disease]

OBJECTIVE

This study was conducted to investigate the effect of chewing fresh or dried betel nut on the inci-dence and canceration of oral mucosa disease in Haikou City in Hainan Province.

METHODS

Through a survey questionnaire, clinical examination, and regular follow-up, we collected clinical data from 1 722 cases and divided them into two groups, among which 704 of the afflicted people chew dried betel nut, whereas the other 1 018 chew fresh betel nut. The data were 
statistically analyzed using different variables which included age, number, time of onset of the disease, and the cancerous condition associated with common oral mucosa disease, including oral submucous fibrosis (OSF), oral leukoplakia (OLK), and oral Lichen planus (OLP).

RESULTS

1) The study found no significant difference in the prevalence of oral mucosa diseases between the dried betel nut group (n=704) and fresh betel nut group (n=1 018) among the 1 722 cases (P>0.05), but the peak age of oral mucosal disease was more advanced in the dried betel nut group (P<0.01). 2) The incidence within 5 years of OSF, OLK, OLP, and oral mucosa diseases in the dried betel nut group was significantly higher than that in the fresh betel nut group (P<0.01). 3) The incidence of cancer for oral mucosa disease in patients included in the dried betel nut group was significantly higher than that in the fresh betel nut group (P<0.01).

CONCLUSIONS

Chewing dried betel nut is more pathogenic and carcinogenic than chewing fresh betel nut. The extremely harmful components of the dried betel nut synergistically play a vital role in the occurrence and carcinogenesis of oral mucosal diseases.

The oral microbiota of patients with recurrent aphthous stomatitis

BACKGROUND

Specific pathogenic bacteria have been implicated in recurrent aphthous stomatitis (RAS), a chronic inflammatory condition characterised by ulcerations in the oral mucosa. However, the aetiology behind this condition still remains unclear.

OBJECTIVE

The buccal microbiota of patients with RAS was compared to that of control subjects to investigate its potential role for this condition.

DESIGN

Buccal swabs were obtained from non-ulcerative areas of 60 patients, of whom 42 patients had lesions at the time of sampling, and 60 healthy age- and gender-matched controls. Bacterial DNA was extracted and analysed by Terminal-Restriction Fragment Length Polymorphism, using enzymatic digestion of the polymerase chain reaction-amplified 16S rRNA gene, yielding a series of peaks, each representing a bacterial taxon.

RESULTS

Two peaks, 60 and 489, were more prevalent in patients with RAS than controls. Conversely, peaks 58 and 490 were less common in patients than controls. When the patients were divided into subgroups, we found that the observed differences in peak-pattern were related to the presence of lesions during sampling.

CONCLUSIONS

The microbiota of the non-inflamed buccal mucosa differed between patients and controls. The differences were most pronounced in patients who presented with lesions during sampling, suggesting that a disturbance in the normal buccal microbiota triggers the presence of lesions or that presence of lesions alters the microbiota.

A new approach to the treatment of recurrent aphthous stomatitis with bioadhesive gels containing cyclosporine A solid lipid nanoparticles: in vivo/in vitro examinations

Aim

To develop a suitable buccal bioadhesive gel formulation containing cyclosporine A solid lipid nanoparticles (CsA SLNs) for the treatment of recurrent aphthous stomatitis.

Methods

The suitability of the prepared formulations for buccal application was assessed by means of rheological studies, textural profile analysis, and ex vivo drug-release studies. Plastic flows, typical gel-like spectra, and suitable mechanical properties were obtained from prepared formulations. The retention time was explored in in vivo distribution studies and the effect of the gel containing CsA SLNs on the healing of oral mucosal ulceration was investigated in an animal model. In vivo distribution studies are a very important indicator of the retention time of formulations at the application site.

Results

Distribution studies showed that 64.76% ± 8.35% of the formulation coded “F8+SLN” remained on the buccal mucosa 6 hours after application. For the second part of the in vivo experiments, 36 rabbits were separated into three groups: the first group was treated with the gel formulation without the active agent; the second group with the gel formulation containing CsA SLNs; and the third group, used as the control group, received no treatment. Wound healing was established by scoring of the rate of wound healing on Days 3, 6, 9, and 12. Histological observations were made on the same days as the scoring studies. The bioadhesive gel formulation that included CsA SLNs increased the rate of mucosal repair significantly.

Conclusion

This study has shown that the bioadhesive gel formulation containing CsA SLNs reported here is a promising candidate for the topical treatment of recurrent aphthous stomatitis.