Analysis of the expression of heat-shock protein 27 in patients with oral lichen planus.

OBJECTIVE: Heat-shock protein 27 (hsp27) has been implicated in several biological events. In this experimental study, we aimed at analysing, for the first time, the expression of hsp27 in the diverse stages of oral lichen planus (OLP) lesions. MATERIALS AND METHODS: Thirty-six biopsy specimens of patients with OLP and 10 of healthy patients were selected. OLP specimens were divided into three groups: G1 - moderate or mildly active OLP; G2 - active or moderately active atrophic OLP; G3 - mild or inactive atrophic OLP. Hsp27 expression was analysed by immunohistochemistry (staining intensity and percentage of stained cells), and results of staining were compared between the different groups. Gender, age and anatomical location were also studied. RESULTS: In the basal layer, an increase of hsp27 expression in both G2 and G3 was observed when compared to G1 and control group. In contrast, a decrease of hsp27 expression in the superficial layer was observed in all groups when compared to control group. CONCLUSION: The increased expression of Hsp27 in the basal layer observed during the OLP evolution and the less staining in the superficial layers in all cases of OLP suggest that hsp27 may have a role in the OLP pathogenesis.

Are oral and dental diseases linked to cancer?

OBJECTIVE: Infection and inflammation play a role in carcinogenesis, and highly prevalent oral and dental diseases have been significantly linked to some types of cancer. This article reviews current literature in this area. MATERIALS AND METHODS: Open literature review using the PubMed database and focused on publications from 2000 to 2010. RESULTS: Numerous potential mechanisms are implicated in the oral disease/carcinogenesis paradigm, including infection- and inflammation-associated cell pathology and microbial carcinogen metabolism. Poor oral hygiene is associated with oral cancer, but there is also evidence of a possible link between oral or dental infections and malignancies in general. CONCLUSION: Oral infections may trigger malignant transformation in tissues of the mouth and other organs. However, scientific evidence to date remains weak and further well-conducted studies are warranted before cancer can be properly added to the list of oral infection-related systemic diseases.

Peri-implant bone mechanobiology. Review of the literature.

UNLABELLED: The mechanical load applied during bone regeneration in implant treatments influences the early formation of peri-implant bone tissue through the activation of different pathways. The aim of this review was to determine the currently available scientific evidence in this field. MATERIAL AND METHOD: Electronic search in medical databases (Medline, Pubmed and Cochrane Library) of experimental studies in animal models published from 2003 to 2009. RESULTS: There is scientific evidence that the immediate application of an axial load in implantology stimulates bone formation, as measured by various histomorphometric parameters. Different physiological mechanisms (e.g., production of nitric oxide, prostaglandin E2) participate in this effect, although their action has not been fully elucidated. CONCLUSION: The precise role of mechanical loading in the osseointegration process remains unknown. Further studies are required to demonstrate the biological mechanisms involved and the load range producing the most effective response and to develop devices for obtaining predictable clinical outcomes.

Oral ulcers: clinical aspects. A tool for dermatologists. Part I. Acute ulcers.

Oral ulcers are generally painful lesions that are related to various conditions developing within the oral cavity. They can be classified as acute or chronic according to their presentation and progression. Acute oral ulcers are be associated with conditions such as trauma, recurrent aphthous stomatitis, Behçet's disease, bacterial and viral infections, allergic reactions or adverse drug reactions. Chronic oral ulcers are associated with conditions such as oral lichen planus, pemphigus vulgaris, mucosal pemphigoid, lupus erythematosus, mycosis and some bacterial and parasitic diseases. The correct differential diagnosis is necessary to establish the appropriate treatment, taking into account all the possible causes of ulcers in the oral cavity. In the first part of this two-part review, acute oral ulcers are reviewed.

Oral ulcers: clinical aspects. A tool for dermatologists. Part II. Chronic ulcers.

Oral ulcers are generally painful lesions that are related to various conditions developing within the oral cavity. They can be classified as acute or chronic according to their presentation and progression. Acute oral ulcers are be associated with conditions such as trauma, recurrent aphthous stomatitis, Behçet's disease, bacterial and viral infections, allergic reactions or adverse drug reactions. Chronic oral ulcers are associated with conditions such as oral lichen planus, pemphigus vulgaris, mucosal pemphigoid, lupus erythematosus, mycosis and some bacterial and parasitic diseases. The correct differential diagnosis is necessary to establish the appropriate treatment, taking into account all the possible causes of ulcers in the oral cavity. In this second part of this two-part review, chronic oral ulcers are reviewed.

A role for the substance P/NK-1 receptor complex in cell proliferation and apoptosis in oral lichen planus.

OBJECTIVES: To determine whether substance P (SP) and NK-1 receptor (NK-1R) are expressed in oral lichen planus (OLP) and are related to cell proliferation and apoptosis in this disease. MATERIAL AND METHODS: Tissue samples from 50 OLP patients and 26 healthy controls were studied. Immunohistochemistry was performed with anti-SP, anti-NK-1R, anti-ki-67 and anti-caspase-3 monoclonal antibodies and the clinical and pathological data of the OLP patients were evaluated. RESULTS: With the exception of NK-1R expression in epithelial cell membrane and cytoplasm, all markers were more frequently present in OLP patients than in controls (P < 0.05). Higher cytoplasmatic expression of NK-1R was associated with higher epithelial expression of caspase-3 (P < 0.05). Higher epithelial expression of NK-1R and SP was associated with higher suprabasal and basal epithelial expression of ki-67 (P < 0.05 and P < 0.005, respectively). CONCLUSIONS: Actions of the SP/NK-1R complex may contribute to the immune disorder underlying OLP and trigger stimuli to induce cell proliferation. These results indicate that this complex might play a role in the malignant transformation of OLP.

Differences in the expression of p53 protein in oral lichen planus based on the use of monoclonal antibodies DO7 and pAb 240.

UNLABELLED: A comparison is made of p53 expression in oral lichen planus, detected via monoclonal antibodies pAb240 and DO7, and with cell apoptosis and proliferation markers. An immunohistochemical study was made of 51 cases of oral lichen planus and 26 controls, using monoclonal antibodies DO7 and pAb240, anti-caspase-3 antibody and Mib-1 antibody against Ki-67. The cases showed important p53 expression with D07 (68%, 36 cases), presumably wild p53, and low p53 expression with pAb240 (14.9%, 7 cases), presumably mutated p53. No significant relationship was observed between p53 expression and caspase-3 apoptosis marker, though an association was recorded between p53 expression with DO7 and Ki-67 expression. CONCLUSIONS: In oral lichen planus, p53 protein preferentially activates the cell cycle for DNA repair, this representing a very effective genome vigilance mechanism, in view of the low rate of malignant transformations observed in this disease.

Update on molecular pathology in oral cancer and precancer.

Oral carcinogenesis is a multifactorial process involving numerous genetic events that alter normal functions of oncogenes and tumour suppressor genes. This may increase the production of growth factors or the number of receptors on the cell surface, and/or increase transcription factors or intracellular signal messengers. Together with the loss of tumour suppressor activity, these changes lead to a cell phenotype that can increase cell proliferation, with loss of cell cohesion, and infiltration of adjacent tissue thus causing distant metastasis. Molecular pathology is responsible for defining the molecular mechanisms that underlie the onset of oral precancer and cancer. The aim of this review is to describe recent advances in our understanding of the molecular control of the innumerable pathways related to these processes. These may lead to short- or medium term improvements in the diagnosis and prognosis of oral precancerous and cancerous lesions and to the development of novel therapeutic approaches to this disease.

No differences in caspase-3 and Bax expression in atrophic-erosive vs. reticular oral lichen planus.

BACKGROUND: Caspase-3 (CPP32) and Bax expression levels in oral lichen planus (OLP) lesions are considered reliable markers of apoptosis. The malignant transformation of OLP remains a very controversial matter. The objective of this study was to compare histological and apoptotic phenomena between atrophic-erosive and reticular forms of OLP. METHODS: Analysis was conducted of biopsy samples from 18 patients with reticular and 14 with atrophic-erosive OLP. Conventional histology techniques were used to quantify histological markers of OLP and peroxidase/anti-peroxidase techniques to determine apoptosis markers caspase-3 (CPP32) and Bax. RESULTS: More Civatte bodies and lymphocyte exocytosis were observed in atrophic-erosive than reticular OLP samples, without any statistical difference. No statistical significant differences in caspase-3 expression were found between these OLP forms in suprabasal layer (58.3% vs. 43.8%), basal layer (83.3% vs. 68.8%) or infiltrate (69.2% vs. 46.6%). Bax expression was relatively infrequent, and no differences were observed between atrophic-erosive and reticular forms. CONCLUSIONS: The low frequency of apoptotic phenomena (caspase-3 and Bax) in epithelial cells of OLP may create a favourable substrate for malignant transformation. However, there does not seem to be an association with the clinical form (atrophic-erosive or reticular).

Prognostic significance of p21WAF1/CIP1, p16INK4a and CD44s in tongue cancer.

The role of lost or reduced expression of p21, p16 and CD44s in the survival of tongue cancer patients was investigated. Tumours and adjacent non-tumour epithelia (ANTE) from 36 patients with tongue cancer were retrospectively studied by immunohistochemistry using monoclonal antibodies against p21, p16 and CD44s proteins. Expression of p21, p16 and CD44s and their relationship with clinical and pathological parameters were analyzed. Of 36 patients, 12 (33.33%) developed recurrence and 12 died of the disease (mean survival, 25.5 months). In four cases (11.1%), concomitant low expression (<50% of tumour cells) of p21, p16 and CD44s was detected but had no effect on survival or recurrence in the univariate analysis. In the multivariate analysis, low expression of CD44s was the sole prognostic factor related to survival (p=0.01, hazards ratio: 0.749). There was no expression of p21, p16 or CD44s in ANTE from 3 out of 24 cases studied, and this finding was related to recurrence in the univariate analysis. In the multivariate analysis, low expression of CD44s in ANTE was again the sole factor related to recurrence (p=0.002, hazards ratio: 0.028). In conclusion, low expression of CD44s is related to tumour cell invasiveness and may be of clinical relevance as a prognostic factor.

Cell cycle regulating mechanisms in oral lichen planus: molecular bases in epithelium predisposed to malignant transformation.

OBJECTIVE: Expression of p53, p21, ki-67, Bcl-2 and caspase-3 proteins in oral lichen planus (OLP) was studied to investigate cell cycle regulation mechanisms in this disease. MATERIAL AND METHODS: Oral biopsies were obtained from 51 patients with OLP and 26 controls for immunohistochemical analysis (peroxidase antiperoxidase) to quantify expression of the proteins under study (-: 0%, +: <10%, ++: 10-25%, +++: 26-50%, ++++: >50% positive cells). RESULTS: Basal expression of caspase-3 was negative in 22 cases (46.8%) and positive in <10% of basal cells in 22 cases (46.8%); caspase-3 expression in inflammatory infiltrate was negative in 22 cases (46.8%) and positive in <10% of lymphocytes in 20 cases (42.5%). Basal expression of Bcl-2 was negative in 35 cases (74.5%); Bcl-2 was expressed in inflammatory infiltrate in 34 cases (72.3%) and was positive in <25% of lymphocytes in 14 of these (29.7%). Basal expression of p53 and p21 was positive in 32 (67.9%) and 23 (48.8%) cases, respectively. Basal expression of ki-67 was positive in 45 cases (95.7%), of which 20 (42.5%) showed positivity in >25% of cells; ki-67 was expressed in inflammatory infiltrate in 23 cases (48.9%). Significant associations were found between basal expressions of p53 and ki-67 (p<0.001) and between Bcl-2 expression in infiltrate and basal expression of ki-67 (p<0.001). No association was observed between basal expressions of p53 and caspase-3 (p=0.08). Bcl-2 expression in infiltrate and basal expression of ki-67 were independently associated with presence of OLP. CONCLUSIONS: Epithelial cells in OLP do not preferentially develop apoptosis but rather cycle arrest or an increased proliferation rate, which may create a suitable substrate for malignant transformation.

Analysis of several risks factors involved in dental caries through multiple logistic regression.

Through multiple logistic regression an epidemiological study was undertaken of the following factors: age, gender, socio-economic status, dental care, toothbrushing, chewing gum, snacking, fluoride, and of their influence on the development of tooth decay. The factors are analysed individually and globally (global model). An initial model was constructed, establishing the interactions, and developing a final model. Risk factors shown to be involved were: low social class status, lack of dental care in the previous 12 months, absence of toothbrushing, and belonging to the age group 9-12 years old. An interaction was established between the following variables: socio-economic status and toothbrushing, and dental care and age.

Terapéutica periodontal de mantenimiento / Supportive periodontal therapy

INTRODUCCIÓN: El mantenimiento es una fase fundamental de la terapia y prevención de las enfermedades periodontales. Los objetivos de esta revisión son: a) Determinar cuáles son los aspectos de la terapia periodontal de mantenimiento; b) conocer el valor del mantenimiento sobre los resultados a largo plazo del tratamiento periodontal; c) revisar los factores de riesgo del paciente, del diente y de la localización; d) establecer un protocolo de acción ante las distintas situaciones. Material, métodos y resultados: Para la realización de este trabajo se han analizado 46 artículos científicos. Para la búsqueda se han empleado la base de datos MEDLINE y Cochrane. DISCUSIÓN: Los objetivos de la terapia de mantenimiento son prevenir la iniciación y recurrencia de las enfermedades periodontales. Independientemente del tipo de tratamiento que realicemos, los parámetros clínicos no mejoraran si el mantenimiento por parte del profesional no se lleva a cabo. Para establecer los intervalos de las citas y las localizaciones a tratar, será fundamental la valoración de los factores de riesgo asociados al paciente, al diente y a la localización

INTRODUCTION: Supportive periodontal therapy (SPT) is an essential phase of periodontal disease prevention and therapy. The objectives of this review are: a) to determine the different aspects from SPT; b) to know the value of SPT in long term results after active periodontal therapy; c) to review the patient, the tooth and the site related risk factors; d) to establish clinical protocols for managing the different situations. Materials, METHODS AND RESULTS: For the preparation of this work, 46 scientific articles have been analyzed the MEDLINE and Cochrane databases have been used to make the search. DISCUSSION: The objectives of SPT are to prevent the initiation or recurrence of periodontal diseases. Independently of the type of treatment, the clinical outcomes won't improve if we don't perform a professional SPT. To establish the appointment intervals and the sites to be treated, we have to evaluate the risk factors associated to the patient, the tooth and the site

Interleukin-1 gene polymorphisms and periodontal status in a Spanish population.

The aim of this study was to investigate the possible association between interleukin (IL)-1A (+4845) and/or IL-1B (+3954) gene polymorphisms and the onset and progression of chronic periodontal disease (PD), an issue that remains controversial. The relationship between IL-1ß concentration in the gingival crevicular fluid (GCF) and disease activity was also evaluated. The study was performed on 25 individuals with no gingivitis or PD and on 25 subjects with active chronic PD. Two samples of GCF were obtained from each subject and IL-1ß was determined by enzyme-linked immunoabsorbent assay. Blood samples (10 ml) were drawn from each subject to detect polymorphisms in IL-1A (+4845) and IL-1B (+3954) by polymerase chain reaction. Mean GCF IL-1ß concentrations were higher in patients with active chronic PD compared to the control group. No significant association was found in either group between GCF IL-1ß concentration and the presence of polymorphisms in IL-1A (+4845), IL-1B (+3954) or both genotypes. No significant difference was found in either group with regard to the presence of polymorphisms in IL-1A (+4845), IL-1B (+3954) or both genotypes (p=0.556). The concentration of IL-1ß in GCF was almost 2-fold higher in patients with chronic PD than in the healthy individuals. The presence of polymorphisms in IL-1A (+4845) and/or IL-1B (+3954) genotypes is not associated with IL-1ß overproduction in GCF and is not a risk factor for chronic PD. IL-1ß is considered a suitable marker of the severity and progression of chronic PD. The presence of IL-1A (+4845) and/or IL-1B +3954 gene polymorphisms does not appear to be a risk factor for chronic PD. Therefore, the IL-1A (+4845) and/or IL-1B +3954 gene polymorphisms cannot be considered genetic markers of chronic PD. Moreover, these polymorphisms do not indicate an overproduction of IL-1ß in GCF.

Multifocal epithelial hyperplasia: A potentially precancerous disease? (Review).

Multifocal epithelial hyperplasia (MEH), also known as Heck's disease, manifests as a papulonodular lesion in the oral mucosa and has been associated with the human papillomavirus, a virus related to various precancerous diseases in the oral cavity. It has a predisposition for the female gender and for children. Although the majority of reported cases have been among American Indians and Eskimos, it has been described in multiple ethnic groups in various geographical locations. The objective of this review was to report on the clinical characteristics and epidemiology of MEH and its possible correlation with oral cancer. It is based on a search of articles in international journals published prior to April 2011, using the PubMed database and selecting articles related to the epidemiology and clinical characteristics of MEH. The review revealed a higher number of cases in individuals of American Indian origin and a predilection of the disease for the female gender and for patients between the 1st and 2nd decades of life. The most frequent lesion site was the lower lip. The disease has been associated with socio-economic and genetic factors, among others. No cases of malignant transformation have been reported.

Concepto actual de la patogénesis de la periimplantitis y el papel que ocupan las bacterias / Actual concept of the pathogenesis of the periimplantitis and the role that bacterial have

A través de una extensa revisión de la literatura, nuestro objetivo será esclarecer el concepto actual que existe sobre la patogénesis de la periimplantitis, así como las implicaciones que pueden tener las bacterias sobre la misma. Hasta la fecha diferentes estudios longitudinales y transversales han identificado algunos de los factores de riesgo o indicadores de riesgo de la periimplantitis. Historia previa de enfermedad periodontal, diabetes, carga genética, pobre higiene oral, tabaco, consumo de alcohol, ausencia de encía queratinizada y la superficie de los implantes son algunos de factores que han sido analizados en detalle en la literatura. La colonización de nuevas superficies implantadas quirúrgicamente suponen una situación de riesgo en pacientes parcialmente edéntulos, donde las bacterias periodontopatógenas de la bolsa residual tienen un importante papel

With the intention of clarifaying the current concept of the pathogenesis of the periimplantitis and the implications that bacteria could have in it, an extensive literature review has been made. Till the date, different longuitudinal and cross-sectional studies have identified some of the periimplantitis risk factors or risk indicators. Factors as history of periodontitis, diabetes, genetic traits, poor oral hygiene, smoking, alcohol consumption, absence of keratinized mucosa and implant surface have been analyzed in detail. The colonization of the surgical implanted new surfaces act as a risky situation for partial edentulous patients, where periodontopathogenic bacteria of the residual pocket have and important role

Methylation in oral cancer and pre-cancerous lesions (Review).

There is considerable interest in the analysis of epigenetic alterations in cancer, including oral cancer and pre-cancerous lesions. These processes affect or inactivate the functions of genes without altering their structure or sequence. One example is the methylation of the promoter region of some genes involved in cell cycle control. Knowledge of methylation patterns is very important for understanding the expression of genes in normal and pathological situations. This review provides an update on research into this issue in oral cancer and pre-cancerous lesions. A greater understanding of this epigenetic alteration could not only assist the diagnosis and prognosis of oral cancer but could also open up novel therapeutic approaches. The presence of methylation in specific tumour suppressor genes could modify their function and alter cell cycle control, so the patients could have an increased risk of developing cancer and also a higher degree of malignancy. The most frequently and extensively studied methylated genes in oral premalignant lesions are p16, MGMT, RARß2, E-cadherin and DAP-kinase.

Técnicas de preservación de alveolo y de aumento del reborde alveolar: Revisión de la literatura / Ridge preservation and ridge augmentation procedures: A literatura review

La pérdida dentaria produce una serie de cambios dimensionales que afectan tanto a los tejidos duros como a los tejidos blandos ocasionando frecuentemente defectos en el reborde alveolar. La prevención y el tratamiento de dichos defectos, tiene como objetivo la preservación o el aumento de los tejidos duros y/o blandos para mejorar las condiciones del reborde para una futura restauración protésica. Existen diversas técnicas quirúrgicas encaminadas a prevenir o minimizar los cambios dimensionales en alveolos postextracción (técnicas de preservación de alveolo) y otras destinadas a la reconstrucción de dichas alteraciones anatómicas. En general, en defectos pequeños o moderados una técnica de aumento de tejidos blandos puede ser suficiente. Sin embargo, en defectos más severos o en aquellas localizaciones en las que se planifique la posterior colocación de implantes, un enfoque combinado (aumento de tejido duros y blandos) y/o en distintas fases puede ser necesario. En este artículo se revisan los cambios dimensionales tras la extracción o pérdida dental, los tipos de la deformidad del reborde así como las diferentes técnicas de preservación de alveolo y de aumento de la cresta alveolar

The extraction of single as well as multiple teeth induces a series of adaptative changes in the soft and hard tissues that results in an overall regress of the edentulous site(s). The prevention and treatment of alveolar ridge deformities aims preserving and reconstructing soft and hard tissues of the edentulous ridge in order to render better conditions at the site for the future prosthesis installation. Different surgical techniques have been proposed to prevent ridge collapse after tooth extraction or to reconstruct the lost anatomy prior to prosthesis installation. In general terms, in mild defects, soft tissue augmentation may be sufficient to repair the deformity. However, in more severe deformities a combined or staged approach may be more appropriate. This article reviews the dimensional changes after tooth extraction, types alveolar ridge deformities and various techniques for the prevention and treatment of alveolar ridge defects

Tratamiento periodontal quirúrgico de lesiones de furca. Revisión narrativa / Surgical treatment of furcation involvement lesions

Las lesiones de furca que afectan a dientes multirradiculares pueden ser tratadas desde diferentes enfoques quirúrgicos tales como la plastia, tunelización y radectomía, así como también con raspado y alisado radicular y técnicas regenerativas, con la extracción como última opción, en función del grado de lesión que presenten. Objetivo: El objetivo ha sido revisar todos los aspectos anatómicos y clínicos a considerar para la toma de decisión diagnostica que nos permita un adecuado enfoque terapéutico. Conclusión: En la elección de la modalidad terapéutica se debe de tener en cuenta que no existe evidencia científica que avale que un procedimiento sea superior a otro

Furcation lesions affecting multirradicular teeth can be treated from different surgical approaches such as angioplasty, tunneling and radectomi and also scaling and root planing and regenerative techniques, with removal as a last resort, depending on the degree of injury submit. Objective: The objective was to review all anatomical and clinical aspects to consider for diagnostic decision making that allows us adequate therapeutic approach. Conclusion: The choice of treatment modality should keep in mind that there is scientific evidence to support that a procedure is superior to another