Nuclear F-actin Cytology in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma.

Oral cavity cancer has a low 5-y survival rate, but outcomes improve when the disease is detected early. Cytology is a less invasive method to assess oral potentially malignant disorders relative to the gold-standard scalpel biopsy and histopathology. In this report, we aimed to determine the utility of cytological signatures, including nuclear F-actin cell phenotypes, for classifying the entire spectrum of oral epithelial dysplasia and oral squamous cell carcinoma. We enrolled subjects with oral potentially malignant disorders, subjects with previously diagnosed malignant lesions, and healthy volunteers without lesions and obtained brush cytology specimens and matched scalpel biopsies from 486 subjects. Histopathological assessment of the scalpel biopsy specimens classified lesions into 6 categories. Brush cytology specimens were analyzed by machine learning classifiers trained to identify relevant cytological features. Multimodal diagnostic models were developed using cytology results, lesion characteristics, and risk factors. Squamous cells with nuclear F-actin staining were associated with early disease (i.e., lower proportions in benign lesions than in more severe lesions), whereas small round parabasal-like cells and leukocytes were associated with late disease (i.e., higher proportions in severe dysplasia and carcinoma than in less severe lesions). Lesions with the impression of oral lichen planus were unlikely to be either dysplastic or malignant. Cytological features substantially improved upon lesion appearance and risk factors in predicting squamous cell carcinoma. Diagnostic models accurately discriminated early and late disease with AUCs (95% CI) of 0.82 (0.77 to 0.87) and 0.93 (0.88 to 0.97), respectively. The cytological features identified here have the potential to improve screening and surveillance of the entire spectrum of oral potentially malignant disorders in multiple care settings.

Risk of Adverse Reactions to Oral Antibiotics Prescribed by Dentists.

Dentists prescribe a large portion of all oral antibiotics, and these are associated with a risk of adverse drug reactions (ADRs). The aim of this study was to quantify the risk of ADRs associated with oral antibiotics commonly prescribed by dentists. NHS Digital Prescribing data and Yellow Card Drug Analysis data for 2010 to 2017 were abstracted to quantify dental antibiotic prescribing in England, and the rate and types of ADRs associated with them. During the period of study, the mean number of actively practicing dentists in England was 23,624. Amoxicillin accounted for 64.8% of dental antibiotic prescribing and had the lowest reported rate of fatal ADRs (0.1/million prescriptions) and overall ADRs (21.5/million prescriptions). Indeed, amoxicillin was respectively 6 and 3 times less likely to cause an ADR than the other penicillins, penicillin V and amoxicillin + clavulanic acid, and appears to be very safe in patients with no history of penicillin allergy. In contrast, clindamycin, which is often used in patients with penicillin allergy, had the highest rate of fatal (2.9/million prescriptions) and overall (337.3/million prescriptions) ADRs, with Clostridiodes (formerly Clostridium) difficile infections pivotal to its ADR profile. Other amoxicillin alternatives, clarithromycin and metronidazole, while significantly worse than amoxicillin, were 3 and nearly 5 times less likely to cause an ADR than clindamycin. Ranked from least to most likely to cause an ADR, antibiotics most commonly prescribed were as follows: amoxicillin < cephalosporins < erythromycin < tetracyclines < azithromycin < metronidazole < amoxicillin + clavulanic acid < clarithromycin < penicillin V < clindamycin. This study confirmed the high level of safety associated with use of amoxicillin by dentists and the significantly worse rates of fatal and nonfatal ADRs associated with other penicillins and alternatives to amoxicillin for those who are penicillin allergic. In particular, clindamycin had the highest rate of fatal and nonfatal ADRs of any of the antibiotics commonly prescribed by dentists.

Pre-clinical evaluation of novel mucoadhesive bilayer patches for local delivery of clobetasol-17-propionate to the oral mucosa.

Oral lichen planus (OLP) and recurrent aphthous stomatitis (RAS) are chronic inflammatory conditions often characterised by erosive and/or painful oral lesions that have a considerable impact on quality of life. Current treatment often necessitates the use of steroids in the form of mouthwashes, creams or ointments, but these are often ineffective due to inadequate drug contact times with the lesion. Here we evaluate the performance of novel mucoadhesive patches for targeted drug delivery. Electrospun polymeric mucoadhesive patches were produced and characterised for their physical properties and cytotoxicity before evaluation of residence time and acceptability in a human feasibility study. Clobetasol-17-propionate incorporated into the patches was released in a sustained manner in both tissue-engineered oral mucosa and ex vivo porcine mucosa. Clobetasol-17 propionate-loaded patches were further evaluated for residence time and drug release in an in vivo animal model and demonstrated prolonged adhesion and drug release at therapeutic-relevant doses and time points. These data show that electrospun patches are adherent to mucosal tissue without causing tissue damage, and can be successfully loaded with and release clinically active drugs. These patches hold great promise for the treatment of oral conditions such as OLP and RAS, and potentially many other oral lesions.

A change in the NICE guidelines on antibiotic prophylaxis.

Since 2008, NICE clinical guidelines have stated: 'Antibiotic prophylaxis against infective endocarditis is not recommended for people undergoing dental procedures'. This put UK guidance at odds with guidance in the rest of the world, where antibiotic prophylaxis is recommended for patients at high-risk of infective endocarditis undergoing invasive dental procedures. Many dentists also felt this wording prohibited the use of antibiotic prophylaxis, regardless of the wishes of the patient or their personal risk of infective endocarditis and made it difficult for them to use their clinical judgment to deliver individualised care in the best interests of their patients. NICE have now changed this guidance to 'Antibiotic prophylaxis against infective endocarditis is not recommended routinely for people undergoing dental procedures.' This article examines the implications of this small but important change.

Guidelines on prophylaxis to prevent infective endocarditis.

Infective endocarditis is a devastating disease with high morbidity and mortality. The link to oral bacteria has been known for many decades and has caused ongoing concern for dentists, patients and cardiologists. Since 2008, the UK has been out of step with the rest of the world where antibiotic prophylaxis is recommended for high-risk patients undergoing invasive dental procedures. Recent evidence that identified an increase in endocarditis incidence prompted a guideline review by NICE and the European Society for Cardiology--which produces guidance for the whole of Europe. Despite reviewing the same evidence they reached completely opposing conclusions. The resulting conflict of opinions and guidance is confusing and poses difficulties for dentists, cardiologists and their patients. Recent changes in the law on consent, however, may provide a patient-centred and pragmatic solution to these problems. This Opinion piece examines the evidence and opposing guidance on antibiotic prophylaxis in the context of the recent changes in the law on consent and provides a framework for how patients at risk of endocarditis might be managed in practice.

NICE and antibiotic prophylaxis to prevent endocarditis.

Infective endocarditis is a devastating disease with high morbidity and mortality. The link to oral bacteria has been known for many decades and has caused on going concern for dentists, patients and cardiologists. Good oral hygiene has long been advocated to prevent endocarditis. Before 2008, antibiotic prophylaxis before invasive dental procedures was also an important strategy for preventing infective endocarditis for patients at risk of the disease in the UK, and still is in most other countries of the world. In 2008, however, NICE published new guidance recommending that antibiotic prophylaxis in the UK should cease. At the time this was a highly controversial decision. New data suggests that there has been a significant increase in the incidence of infective endocarditis since the 2008 guidelines. The 2008 guidance is being reviewed and draft new guidance is being put out for public consultation. This article discusses the issues raised by the new data and the questions that should be addressed in the review and public consultation.

Association of MMP but not TIMP-1 gene polymorphisms with recurrent aphthous stomatitis.

OBJECTIVES: Recurrent aphthous stomatitis (RAS) is a common oral inflammatory disease induced by genetic and environmental factors. Gelatinases (MMP-2 and MMP-9) and their natural inhibitor TIMP-1 are active players in the inflammatory process. We aimed to determine whether inheritance of specific MMP-2, MMP-9, or TIMP-1 gene polymorphisms is associated with RAS susceptibility. SUBJECTS AND METHODS: Ninety-six RAS patients and 153 healthy controls were studied. Five polymorphisms were genotyped: rs17576, rs3918242, and rs11697325 in MMP-9, MMP-2 rs2285053, and TIMP-1 rs6609533. Association was assessed by logistic regression analysis after adjustment for confounding factors. Linkage disequilibrium (LD) was assessed using the Haploview program. RESULTS: MMP-9 rs11697325 was significantly associated with RAS, with an increase in the AA genotype in patients, determined using χ(2) analysis (OR = 2.3, P = 0.006) and adjusted regression analysis (OR = 3.1, P = 0.009). MMP-9 rs11697325 and rs17576 showed strong LD (D' = 0.95), with an increase in the AA haplotype (P = 0.023) and a decrease in the GA haplotype (P = 0.015) in patients. CONCLUSIONS: This is the first study to investigate the association of MMPs or TIMP-1 with RAS. We found a significant association between MMP-9 rs11697325 polymorphisms and RAS. Confirmatory studies in other populations and functional investigations are needed to determine the role of these genes in RAS.

NICE guidance on antibiotic prophylaxis to prevent infective endocarditis: a survey of clinicians' attitudes.

BACKGROUND: Since the introduction of the National Institute for Health and Clinical Excellence (NICE) guideline (CG064) in 2008 recommending cessation of antibiotic prophylaxis (AP) against infective endocarditis (IE), low level prescribing persists in the UK and is a potential reason why there has been no significant change in the general upward trend in cases of IE. AIM: To undertake a survey of dentists (Ds), cardiologists and cardiothoracic surgeons (C/CTSs) and infection specialists (ISs) to determine why this might be the case. DESIGN: Internet questionnaire-based survey. METHODS: A questionnaire was distributed by email to specialists via UK national societies. RESULTS: A total of 1168 responses were received. All the specialist groups are aware of the guideline (99%). Ds are broadly satisfied, whereas C/CTSs are not. Most Ds follow the NICE guidance (87%), whereas many C/CTSs (39%) do not; ISs adopt a middle course (56%). Even amongst Ds, a significant proportion believe that patients with a prosthetic heart valve (25%) or previous history of IE (38%) should receive AP. A total of 36% of Ds have prescribed AP since March 2008 and many have undertaken procedures where AP has been prescribed by someone else. The majority of respondents (65%) feel that more evidence is required, preferably in the form of a randomized controlled trial. CONCLUSION: Many patients perceived to be at high risk of IE are still receiving AP in conflict with current NICE guidance.

Tissue-engineered oral mucosa.

Advances in tissue engineering have permitted the three-dimensional (3D) reconstruction of human oral mucosa for various in vivo and in vitro applications. Tissue-engineered oral mucosa have been further optimized in recent years for clinical applications as a suitable graft material for intra-oral and extra-oral repair and treatment of soft-tissue defects. Novel 3D in vitro models of oral diseases such as cancer, Candida, and bacterial invasion have been developed as alternatives to animal models for investigation of disease phenomena, their progression, and treatment, including evaluation of drug delivery systems. The introduction of 3D oral mucosal reconstructs has had a significant impact on the approaches to biocompatibility evaluation of dental materials and oral healthcare products as well as the study of implant-soft tissue interfaces. This review article discusses the recent advances in tissue engineering and applications of tissue-engineered human oral mucosa.

Development of tissue-engineered models of oral dysplasia and early invasive oral squamous cell carcinoma.

BACKGROUND: Current organotypic models of dysplasia and oral squamous cell carcinoma (OSCC) lack the complexity that mimics in vivo tissue. Here we describe a three-dimensional in vitro model of the oral epithelium that replicates tumour progression from dysplasia to an invasive phenotype. METHODS: The OSCC cell lines were seeded as a cell suspension (D20, Cal27) or as multicellular tumour spheroids (FaDu) with oral fibroblasts on to a de-epidermised acellular dermis to generate tissue-engineered models and compared with patient biopsies. RESULTS: The D20 and Cal27 cells generated a model of epithelial dysplasia. Overtime Cal27 cells traversed the basement membrane and invaded the connective tissue to reproduce features of early invasive OSCC. When seeded onto a model of the normal oral mucosa, FaDu spheroids produced a histological picture mimicking carcinoma in situ with severe cellular atypia juxtaposed to normal epithelium. CONCLUSION: It is possible to culture in vitro models with the morphological appearance and histological characteristics of dysplasia and tumour cell invasion seen in vivo using native dermis. Such models could facilitate study of the molecular processes involved in malignant transformation, invasion and tumour growth as well as in vitro testing of new treatments, diagnostic tests and drug delivery systems for OSCC.

Qat and its health effects.

In Southern Arabia and Eastern Africa, qat chewing is a widely practised socio-cultural habit. It consists of placing the green-leaved plant into the mucobuccal fold and chewing it for several hours, with subsequent release of psychoactive agents. Qat chewing is often accompanied by smoking tobacco. The reported prevalence of qat chewing in Europe and North America is on the increase with global migration. Oral diseases reportedly associated with qat chewing include periodontitis, oral leukoplakia and oral cancer. However, precise data on the association of qat use with the development of oral cancer are sparse. The aim of this review is to 1) Educate health clinicians about qat usage and related oral/systemic health issues; and 2) Review the current literature regarding qat use and its association with oral disease but more specifically review its link with oral leukoplakia and oral squamous cell carcinoma (OSCC). To do this we searched the literature (PubMed, Science Direct and Scopus) to identify all relevant articles published over the last 20 years using a combination of terms 'qat', 'khat', 'kat', 'cathinone' and 'cathaedulis'.

Development, optimization and characterization of a full-thickness tissue engineered human oral mucosal model for biological assessment of dental biomaterials.

Restorative dental materials and oral health care products come into direct contact with oral mucosa and can cause adverse reactions. In order to obtain an accurate risk assessment, the in vitro test model must reflect the clinical situation as closely as possible. The aim of this study was to develop and optimize a three-dimensional full-thickness engineered human oral mucosal model, which can be used for biological assessment of dental materials. In this study human oral fibroblasts and keratinocytes were isolated from patients and seeded onto a number of collagen-based and synthetic scaffolds using a variety of cell seeding techniques and grown at the air/liquid interface to construct human oral mucosa equivalents. Suitability of 10 different scaffolds for engineering human oral mucosa was evaluated in terms of biocompatibility, biostability, porosity, and the ability to mimic normal human oral mucosa morphology. Finally an optimized full-thickness engineered human oral mucosa was developed and characterized using transmission electron microscopy and immunostaining. The oral mucosa reconstruct resembled native human oral mucosa and it has the potential to be used as an accurate and reproducible test model in mucotoxicity and biocompatibility evaluation of dental materials.

Tissue-engineered oral mucosa: a review of the scientific literature.

Tissue-engineered oral mucosal equivalents have been developed for clinical applications and also for in vitro studies of biocompatibility, mucosal irritation, disease, and other basic oral biology phenomena. This paper reviews different tissue-engineering strategies used for the production of human oral mucosal equivalents, their relative advantages and drawbacks, and their applications. Techniques used for skin tissue engineering that may possibly be used for in vitro reconstruction of human oral mucosa are also discussed.

A systematic review of placebo-controlled randomized clinical trials of treatments used in oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is one of the commoner conditions seen in oral medicine clinics. Current treatments are palliative rather than curative. Numerous treatments have been tried but many have not been evaluated in randomized controlled trials (RCTs). OBJECTIVES: To review the effectiveness and safety of any therapy compared with placebo for the treatment of symptomatic OLP. METHODS: A systematic review of 11 RCTs, totalling 223 patients was done. The main outcome measures used were improvement of signs (erythema, reticulation, ulceration) and symptoms (pain, discomfort) usually after 8 weeks of therapy. RESULTS: Eleven interventions were grouped into four therapeutic classes (topical ciclosporins, topical or systemic retinoids, topical steroids and phototherapy) for comparison. No therapy was replicated exactly. Trials recording the same outcomes in each therapeutic class were pooled. The largest number of pooled trials was four. Small odds ratios with very wide confidence intervals indicating statistically significant but imprecisely known treatment benefits were seen in all but one trial. Only systemic agents were associated with treatment toxicities; all other side-effects were mild and mainly local. CONCLUSIONS: The results are tempered by the small study sizes, lack of replication, lack of standardized outcome measures and the very high likelihood of publication bias. Therefore this review provides only circumstantial evidence for the superiority of the assessed interventions over placebo for the palliation of symptomatic OLP. There is a need for larger placebo-controlled RCTs with carefully selected and standardized outcome measures.

Polymorphisms in the IL-10 and IL-12 gene cluster and risk of developing recurrent aphthous stomatitis.

BACKGROUND: Recurrent aphthous stomatitis (RAS) is a common, painful, ulcerative condition of the mouth. Although there is no clear genetic mode of inheritance, there is evidence that inheritance of specific gene polymorphisms may predispose individuals to RAS. AlsoTh1 cell mediated immune responses under the control of IL-10/IL-12 are thought to play an important role in its pathogenesis. OBJECTIVE: The objective of this study was to investigate the possibility that susceptibility to RAS is associated with the inheritance of specific gene polymorphisms for the T cell regulatory cytokines interleukin-10 (IL-10) and interleukin-12 (IL-12). PATIENTS AND METHODS: One hundred RAS patients and 91 ethnically matched controls were genotyped for the IL-10-592, and -1082 polymorphisms, and the IL-12 1188 polymorphism. Chi-square analysis was used to compare the allele frequencies and genotypes of cases and controls. RESULTS: No significant association was identified between inheritance of specific alleles or genotypes of the IL-10-592 and -1082 polymorphisms or IL-12 1188 polymorphism and susceptibility to RAS. CONCLUSIONS: We were unable to demonstrate an association between the inheritance of specific IL-10 or IL-12 gene polymorphisms and RAS susceptibility.

Oral mucosal keratinocytes express RANTES and ICAM-1, but not interleukin-8, in oral lichen planus and oral lichenoid reactions induced by amalgam fillings.

Oral lichen planus (OLP) is a chronic inflammatory disease of the oral mucosa characterized by a band-like accumulation of lymphocytes in the connective tissue adjacent to the basement membrane as well as intraepithelially. Amalgam fillings can induce oral lichenoid reactions (OLR) that are similar to OLP. The adhesion molecule ICAM-1 and the chemokines interleukin-8 and RANTES all play central roles in leucocyte trafficking. The aim of this study was to investigate the possible role of these molecules in the migration of leucocytes into the oral mucosa in OLP and OLR. Standard immunoperoxidase techniques were used to visualize the expression of ICAM-1, RANTES and interleukin-8 in frozen biopsy sections. ICAM-1 was expressed by endothelial cells, but not by keratinocytes, in normal oral mucosa. ICAM-1 was expressed by keratinocytes in 11 of 12 biopsies of OLP and in six of seven biopsies of OLR. In all of these cases ICAM-1 was also expressed by endothelial cells and leucocytes. Although not present in normal oral mucosa, RANTES was expressed by keratinocytes in 21 of 24 biopsies of OLP and in seven of seven cases of OLR. Interleukin-8 was not detected in any of the samples. The expression of ICAM-1 and RANTES by epithelial keratinocytes in the oral mucosa in OLP and OLR could be a key inflammatory mechanism in these diseases.