[Tobacco-associated lesions of the oral mucosa]

Consumption of tobacco can result not only in a multitude of different general health problems like carcinoma of the lung, ischaemic cardiac diseases, peripheral vascular diseases, stroke, chronic-obstructive pulmonary diseases or peptic ulcers, but also in pathologic lesions of the oral mucosa. Benign oral lesions from smoking or consumption of smokeless tobacco are the so-called smoker's palate and smoker's melanosis. On the other hand, tobacco-associated lesions like oral leukoplakia or oral squamous cell carcinoma are already potentially life-threatening diseases that in general require active treatment. The following review article will present and discuss the typical lesions of the oral mucosa that result from chronic tobacco consumption. The aim of this article is to demonstrate dental health care providers the needs and benefits of tobacco use cessation in a dental setting, especially regarding stomatologic sequelae and consequences. The present article is the first in a series of articles from the Swiss task force "Smoking - Intervention in the private dental office" on the topic "tobacco use and dental medicine".

[Precancerous and high risk lesions of the oral mucosa--Diagnosis, therapy and follow-up in two cases]

Stomatologic lesions at risk to develop an oral squamous cell carcinoma (OSCC) such as oral leukoplakia, erythroplakia/erythroleukoplakia, or oral lichen planus, need an early detection, diagnosis and a long-term/lifelong follow-up to prevent malignant transformation. In the following report, two patients are presented with oral mucosal lesions, who were referred, diagnosed, treated, and underwent follow-up examinations at the Stomatology Service of the Department of Oral Surgery and Stomatology at the University of Bern. These two cases emphasize the importance of early detection and managment of precancerous lesions or initial stages of OSCC. Additionally, risk factors, such as tobacco and alcohol consumption and their influence on stomatologic lesions and their prognosis, will be discussed.

[Oral erythroplakia and erythroleukoplakia: red and red-white dysplastic lesions of the oral mucosa--part 2: cytodiagnosis, pathogenesis, therapy, and prognostic aspects]

The second part of the present review article presents and discusses the current literature regarding cytodiagnostic aspects, pathogenesis, therapy, incidence of recurrence, and malignant transformation rate of oral erythroplakia (OE) and oral erythroleukoplakia (OEL). Oral cytopathology, eventually in combination with DNA cytometry, can add valuable information to conventional histopathology, but is not able yet to replace the aforementioned. Numerous molecular genetic variants have been studied in precancerous lesions to gain knowledge about the prognosis of these lesions. Still, there are no evidence-based parameters available to safely detect precursor lesions that will undergo malignant transformation in the future. Excision of OE and OEL should be performed with a margin of safety using the CO2 laser or a scalpel. Data about incidence of recurrence and malignant tranformation rates of OE are mostly based upon case reports or case series. The OEL has a significantly higher risk of malignant transformation than oral leukoplakias.

[Oral erythroplakia and erythroleukoplakia: red and red-white dysplastic lesions of the oral mucosa--part 1: epidemiology, etiology, histopathology and differential diagnosis]

Oral erythroplakia (OE) and oral erythroleukoplakia (OEL; synonym: speckled leukoplakia) are working diagnoses for red and red-white lesions of the oral mucosa after exclusion of all other possible diagnoses for lesions with a similar clinical appearance. A good knowledge of oral medicine and possible differential diagnoses of oral mucosal pathologies is mandatory to correctly detect OE and OEL on this exclusion basis. In the present review article in a series of two, epidemiologic data, etiologic factors, possible differential diagnoses, and the histopathologic characteristics of OE and OEL will be presented and discussed regarding the current literature. A thorough histopathologic examination of these epithelial precursor lesions is mandatory to recognise the presence and the severity of epithelial dysplasia, which is a decisive factor for the subsequent treatment planning.

Lysyl oxidase expression is an independent marker of prognosis and a predictor of lymph node metastasis in oral and oropharyngeal squamous cell carcinoma (OSCC)

Proteins of the lysyl oxidase (LOX) family are important modulators of the extracellular matrix. However, they have an important role in the tumour development as well as in tumour progression. To evaluate the diagnostic and prognostic value of the LOX protein in oral and oropharyngeal squamous cell carcinoma (OSCC) we performed QRT-PCR and immunohistochemical analysis on two tissue microarrays (622 tissue samples in total). Significantly higher LOX expression was detected in high grade dysplastic oral mucosa as well as in OSCC when compared to normal oral mucosa (P < 0.001). High LOX expression was correlated with clinical TNM stage (P = 0.020), lymph node metastases for the entire cohort (P < 0.001), as well as in the subgroup of small primary tumours (T1/T2, P < 0.001). Moreover, high LOX expression was correlated with poor overall survival (P = 0.004) and disease specific survival (P = 0.037). In a multivariate analysis, high LOX expression was an independent prognostic factor, predicting unfavourable overall survival. In summary, LOX expression is an independent prognostic biomarker and a predictor of lymph node metastasis in OSCC. Moreover, LOX overexpression may be an early phenomenon in the pathogenesis of OSCC and thus an attractive novel target for chemopreventive and therapeutic strategies.

CO2 and diode laser for excisional biopsies of oral mucosal lesions. A pilot study evaluating clinical and histopathological parameters

PURPOSE: The present pilot study evaluates the histopathological characteristics and suitability of CO2 and diode lasers for performing excisional biopsies in the buccal mucosa with special emphasis on the extent of the thermal damage zone created. PATIENTS AND METHODS: 15 patients agreed to undergo surgical removal of their fibrous hyperplasias with a laser. These patients were randomly assigned to one diode or two CO2 laser groups. The CO2 laser was used in a continuous wave mode (cw) with a power of 5 W (Watts), and in a pulsed char-free mode (cf). Power settings for the diode laser were 5.12 W in a pulsed mode. The thermal damage zone of the three lasers and intraoperative and postoperative complications were assessed and compared. RESULTS: The collateral thermal damage zone on the borders of the excisional biopsies was significantly smaller with the CO, laser for both settings tested compared to the diode laser regarding values in pm or histopathological index scores. The only intraoperative complication encountered was bleeding, which had to be controlled with electrocauterization. No postoperative complications occurred in any of the three groups. CONCLUSIONS: The CO2 laser seems to be appropriate for excisional biopsies of benign oral mucosal lesions. The CO2 laser offers clear advantages in terms of smaller thermal damage zones over the diode laser. More study participants are needed to demonstrate potential differences between the two different CO2 laser settings tested.

Diffuse swelling of the buccal mucosa and palate as first and only manifestation of an extranodal non-Hodgkin 'double-hit' lymphoma: report of a case

Most of the lymphomas arising in the oral cavity are of B-cell origin. Among these, diffuse large B-cell lymphomas are the most common. Diffuse large B-cell lymphomas may exhibit more than one chromosomal rearrangement and are then referred to as 'double-hit' or 'triple-hit' lymphomas.

Oral leukoplakia in China: a review

BACKGROUND: Most prevalence studies on oral leukoplakia (OL) in China have been published in the Chinese language. The present review on the literature in Chinese aimed at making the data available to colleagues who are not familiar with the Chinese language. METHODS: The overall rate and 95% confidence interval of OL were calculated using Excel 2003. RESULTS: Overall prevalence of OL was 9.18% (95%CI = 9.06-9.30%). Gender ratio of prevalence was 8.03:1 (males/females). Prevalence was high in age groups over 40 years with the highest in the group aged 60-69 years (21.04%, 95%CI = 19.95-22.13%). The buccal mucosa was most commonly affected (47.08%, 95%CI = 46.52-47.64%), followed by lip (39.09%), palate (9.85%), gingiva (1.80%), and tongue (1.46%). The prevalence in smokers was 23.43% and in non-smokers 1.93%. Among three variants of smoking, the traditional Hanyan pipe smoking carried the highest risk for the development of OL followed by cigarette and Shuiyan water pipe smoking. The rate of alcohol drinkers with OL was 54.50% and 22.21% in individuals without OL. No case of oral cancer was found in six surveys. CONCLUSIONS: The present data on the prevalence of OL in China are comparable to those in other parts of the world. Some traditional smoking habits, however, are particular to certain regions of China.

Pulse or hyaline ring granuloma. Review of the literature on etiopathogenesis of oral and extraoral lesions

Since the late 1950s, reports on an unusual giant-cell granulomatous lesion affecting the jaws, lungs, stomach and intestines have been published. Histopathologically, the lesions showed the presence of structureless hyaline rings with multinucleated giant cells. The aim of this review was to summarize the literature on the etiopathogenesis of the so-called oral and extraoral pulse or hyaline ring granuloma. Literature was searched using PubMed and Medline. In addition, hand search was performed. Search words were oral and extraoral hyaline ring granuloma, giant-cell hyaline angiopathy, pulse granuloma and chronic periostitis. Numerous terms for hyaline ring granuloma have been introduced over time (1971-2008). One hundred seventy-three cases of oral hyaline ring granuloma have been retrieved from the literature. In the mandible, 72.3% occurred . Two theories for etiopathogenesis have been proposed: (1) the origin of the hyaline rings is due to a foreign material (pulse and legumes) having penetrated the oral mucosa or gastrointestinal tract and lungs (exogenous theory) and (2) the rings are due to hyaline degenerative changes in walls of blood vessels (endogenous theory). Experimental production of oral and extraoral hyaline ring granulomas is consistent with the exogenous origin. Particles or remains of leguminous cells having been implanted or aspirated into human tissues whether located to the oral cavity or throughout the entire digestive tract and respiratory system are thought to be causative. Pulse or hyaline ring granulomas are rare but are well-defined oral and extraoral lesions due to implantation of the cellulose moiety of plant foods in contrast to the starch components.

Oral mucosal morphea: a new variant

Morphea is a cutaneous disorder characterized by an excessive collagen deposition. While in almost all cases the sclerosing process exclusively affects the skin, there are anecdotal cases in which associated mucosal involvement has been described. We here report the case of a woman developing a whitish indurated plaque over the left upper vestibular mucosa and hard palate leading to dental mobility and exposure of the roots of several teeth. Cone beam computed tomography of the left maxilla showed bone resorption involving the upper cuspid to the second molar region with widened periodontal ligament spaces, while light microscopy studies demonstrated epithelial atrophy and fibrosis of the dermis extending into the submucosa with hyalinization of subepithelial collagen. Our observation expands the spectrum of clinical presentations of morphea and provides the first example of isolated oral morphea. Its recognition is important to avoid significant local complications.

Patients' awareness of the potential benefit of smoking cessation. A study evaluating self-reported and clinical data from patients referred to an oral medicine unit

The present study analyzed history of smoking and willingness to quit smoking in patients referred for diagnosis and treatment of different oral mucosal lesions. Prior to the initial clinical examination, patients filled in a standardized questionnaire regarding their current and former smoking habits and willingness to quit. Definitive diagnoses were classified into three groups (benign/reactive lesions, premalignant lesions and conditions, and malignant diseases) and correlated with the self-reported data in the questionnaires. Of the 980 patients included, 514 (52%) described themselves as never smokers, 202 (21%) as former smokers, and 264 (27%) as current smokers. In the group of current smokers, 23% thought their premalignant lesions/conditions were related to their smoking habit, but only 15% of the patients with malignant mucosal diseases saw that correlation. Only 14% of the smokers wanted to commence smoking cessation within the next 30 days. Patients with malignant diseases (31%) showed greater willingness to quit than patients diagnosed with benign/reactive lesions (11%). Future clinical studies should attempt (1) to enhance patients' awareness of the negative impact of smoking on the oral mucosa and (2) to increase willingness to quit in smokers referred to a dental/oral medicine setting.

Microbiota in the oral subgingival biofilm is associated with obesity in adolescence

To test the hypothesis whether microbiota in oral biofilm is linked with obesity in adolescents we designed this cross-sectional study. Obese adolescents (n = 29) with a mean age of 14.7 years and normal weight subjects (n = 58) matched by age and gender were examined with respect to visible plaque index (VPI%) and gingival inflammation (bleeding on probing (BOP%)). Stimulated saliva was collected. They answered a questionnaire concerning medical history, medication, oral hygiene habits, smoking habits, and sociodemographic background. Microbiological samples taken from the gingival crevice was analyzed by checkerboard DNA-DNA hybridization technique. The sum of bacterial cells in subgingival biofilm was significantly associated with obesity (P < 0.001). The link between sum of bacterial cells and obesity was not confounded by any of the studied variables (chronic disease, medication, VPI%, BOP%, flow rate of whole saliva, or meal frequency). Totally 23 bacterial species were present in approximately threefold higher amounts, on average, in obese subjects compared with normal weight controls. Of the Proteobacteria phylum, Campylobacter rectus and Neisseria mucosa were present in sixfold higher amounts among obese subjects. The association between obesity and sum of bacterial cells in oral subgingival biofilm indicates a possible link between oral microbiota and obesity in adolescents.

Oral lichenoid contact lesions induced by areca nut and betel quid chewing: a mini review

Betel quid (BQ) and areca nut chewing is widely prevalent in many parts of Asia and Asian-migrant communities throughout the world. Global reports estimate 600 million users. Sufficient evidence of carcinogenicity has been found for BQ and its main ingredient, areca nut. BQ areca nut users have an increased risk of potentially malignant disorders. Among chewers, BQ remains in contact with the oral mucosa for prolonged periods. This review examines the clinical and pathological aspects of lichenoid lesions caused by areca nut and BQ, a condition that has received little attention in the published literature.

Oral lichen planus and malignant transformation: a retrospective follow-up study of clinical and histopathologic data

OBJECTIVE: Patients in the stomatology service of the Department of Oral Surgery and Stomatology who were clinically and histopathologically diagnosed with oral lichen planus (OLP) in the years 1995 to 2001 were examined for a possible malignant transformation of a previously biopsied OLP site. METHOD AND MATERIALS: For the 145 patients included, the recordings were searched for initial localization and type of OLP lesion, potential noxious agents, distribution between symptomatic and asymptomatic OLP types, and for a malignant transformation of a known OLP site during the follow-up period up to December 2003. RESULTS: The group comprised 47 men and 98 women with a mean age of 56.3 years. Of the 497 lesions, almost half were classified as reticular or papular, predominantly located on the buccal mucosa, gingiva, and borders of the tongue. Four patients did not adhere to their scheduled control visits and were dropped from the study. During the follow-up period 4 patients developed malignant transformation of OLP. In 3 of these cases, dysplasia was present at the initial diagnosis of OLP. This results in a malignant transformation rate of 2.84% among the remaining 141 patients; if the 3 patients with initial dysplasia are excluded, the rate drops to 0.71%. CONCLUSIONS: Until further knowledge is derived from large prospective studies, the data supporting or negating a potential malignant character of OLP lesions remains inconclusive. Special emphasis has to be directed toward unified inclusion and exclusion criteria regarding clinical and histologic findings and identifiable risk factors to allow the comparison of different studies.

Morphogenesis of the peri-implant mucosa: an experimental study in dogs

PURPOSE: The objective of the present experiment was to study the morphogenesis of the mucosal attachment to implants made of c.p. titanium. MATERIAL AND METHODS: All mandibular premolars were extracted in 20 Labrador dogs. After a healing period of 3 months, four implants (ITI Dental Implant System) were placed in the right and left sides of the mandible. A non-submerged implant installation technique was used and the mucosal tissues were secured to the conical marginal portion of the implants with interrupted sutures. The sutures were removed after 2 weeks and a plaque control program including daily cleaning of the remaining teeth and the implants was initiated. The animals were sacrificed and biopsies were obtained at various intervals to provide healing periods extending from Day 0 (2 h) to 12 weeks. The mandibles were removed and placed in the fixative. The implant sites were dissected using a diamond saw and processed for histological analysis. RESULTS: Large numbers of neutrophils infiltrated and degraded the coagulum that occupied the compartment between the mucosa and the implant during the initial phase of healing. At 2 weeks after surgery, fibroblasts were the dominating cell population in the connective tissue interface but at 4 weeks the density of fibroblasts had decreased. Furthermore, the first signs of epithelial proliferation were observed in specimens representing 1-2 weeks of healing and a mature barrier epithelium occurred after 6-8 weeks of healing. The collagen fibers of the mucosa were organized after 4-6 weeks of healing. CONCLUSION: It is suggested that the soft-tissue attachment to implants placed using a non-submerged installation procedure is properly established after several weeks following surgery.