Tooth Loss and Caries Experience of Elderly Chileans in the Context of the COVID-19 Pandemic in Five Regions of Chile.

Risk factors associated with tooth loss have been studied; however, the current status of the epidemiological profiles and the impact of the pandemic on the oral health of the elderly is still unknown. This study aims to determine the experience of caries and tooth loss among elderly Chilean citizens in five regions and to identify the risk factors associated with tooth loss. The sample includes 135 participants over 60 years old assessed during COVID-19 lockdown. Sociodemographic variables such as education and RSH (Social Registry of Households) were obtained through a teledentistry platform called TEGO. The history of chronic diseases such as diabetes, obesity, depression and dental caries reported by DMFT index scores were incorporated. The statistical analysis included Adjusted Odds Ratios (ORs) to assess risk factors associated with the lack of functional dentition. Multivariate hypothesis testing was used to compare the mean equality of DMFT and its components between regions (p-value < 0.05). Individuals with RSH ≤ 40% were at higher risk of having no functional dentition with OR 4.56 (95% CI: 1.71, 12.17). The only mean difference between regions was the filled tooth component. Tooth loss was associated with multidimensional lower income, where the elderly belonging to the 40% most vulnerable population had a higher prevalence of non-functional dentition. This study highlights the importance of implementing a National Oral Health Policy that focuses on oral health promotion and minimally invasive dentistry for the most vulnerable population.

Histological and Immunohistochemical Analysis of Peri-Implant Soft and Hard Tissues in Patients with Peri-Implantitis.

Currently, researchers are focused on the study of cytokines as predictive biomarkers of peri-implantitis (PI) in order to obtain an early diagnosis and prognosis, and for treatment of the disease. The aim of the study was to characterize the peri-implant soft and hard tissues in patients with a peri-implantitis diagnosis. A descriptive observational study was conducted. Fifteen soft tissue (ST) samples and six peri-implant bone tissue (BT) samples were obtained from 13 patients who were diagnosed with peri-implantitis. All the samples were processed and embedded in paraffin for histological and immunohistochemical analyses. A descriptive and quantitative analysis of mast cells and osteocytes, A proliferation-inducing ligand (APRIL), B-cell activating factor (BAFF), osteonectin (ON), and ∝-smooth muscle actin (∝-SMA) was performed. We observed the presence of mast cells in peri-implant soft tissue in all samples (mean 9.21 number of mast cells) and osteocytes in peri-implant hard tissue in all samples (mean 37.17 number of osteocytes). The expression of APRIL-ST was 32.17% ± 6.39%, and that of APRIL-BT was 7.09% ± 5.94%. The BAFF-ST expression was 17.26 ± 12.90%, and the BAFF-BT was 12.16% ± 6.30%. The mean percentage of ON was 7.93% ± 3.79%, and ∝-SMA was 1.78% ± 3.79%. It was concluded that the expression of APRIL and BAFF suggests their involvement in the bone resorption observed in peri-implantitis. The lower expression of osteonectin in the peri-implant bone tissue can also be associated with a deficiency in the regulation of bone remodeling and the consequent peri-implant bone loss.

Prevention of oral cancer through the implementation of a teledentistry platform for the elderly / Prevención del cáncer oral mediante la implementación de una plataforma de teleodontología para adultos mayores

Objective: To contribute to early diagnosis of lesions in older patients, including potentially malignant lesions or those suspected of oral cancer by support of a web-based teledentistry platform. Material and Methods:This report contains information from 27 patients with oral lesions out of a total of 135 who received mobile dental care. Specialists who participated in the study involved professionals from the disciplines of periodontics, temporomandibular disorders, oral implantology, oral radiology, oral pathology and geriatrics. Referral consultations were carried out synchronously or asynchronously. Clinical information sent to oral pathology specialists involved a medical history and a traditional description of the lesion which considered size, color, limits, symptomatology, type of surface, consistency, location, and evolution. This information was complemented with a three-dimensional representation of the lesion, simulating an extra/intra oral clinical examination including a marker tool that allows to perform the anatomical-referencing of oral lesions. Results:27 consultations from 26 patients were evaluated for oral pathology lesions. 12 lesions were diagnosed as reactive, 5 were infectious lesions, 4 of vascular etiology, 3 pigmented lesions (amalgam tattoo and smoking-related melanosis) and 3 potentially malignant lesions. The most frequent location was the tongue with 8 cases, followed by the gingiva and jugal mucosa, each with 5 cases. Four lesions required biopsy and histopathological report. Conclusion: A teledentistry platform including digital representations of oral lesions using different digital markers, also associated with a mobile system to provide dental care, constitutes an excellent tool to treat patients that present oral lesions with potential cancer risk.

Objetivo: Contribuir al diagnóstico precoz de lesiones en pacientes mayores, incluyendo lesiones potencialmente malignas o con sospecha de cáncer oral mediante el apoyo de una plataforma de teleodontología basada en la web.Material y Métodos: Este informe contiene información de 27 pacientes con lesiones orales de un total de 135 que recibieron atención odontológica móvil. Los especialistas que participaron en el estudio incluyeron profesionales de las disciplinas de periodoncia, trastornos temporomandibulares, implantología oral, radiología oral, patología oral y geriatría. Las interconsultas se realizaron de forma sincrónica o asincrónica. La información clínica enviada a los especialistas en patología oral involucró una historia clínica y una descripción tradicional de la lesión que consideró tamaño, color, límites, sintomatología, tipo de superficie, consistencia, localización y evolución. Esta información se complementó con una representación tridimensional de la lesión, simu-lando un examen clínico extra/intraoral incluyendo una herramienta marcadora que permite realizar la referenciación anatómica de las lesiones orales. Resultados: Se evaluaron 27 consultas de 26 pacientes por lesiones de patología bucal. Se diagnosticaron 12 lesiones como reactivas, 5 lesiones infecciosas, 4 de etiología vascular, 3 lesiones pigmentadas (tatuaje de amalgama y melanosis por tabaquismo) y 3 lesiones potencialmente malignas. La localización más frecuente fue lengua con 8 casos, seguida de encía y mucosa yugal con 5 casos cada una. Cuatro lesiones requirieron biopsia e informe histopatológico. Conclusión: Una plataforma de teleodontología que incluye representaciones digitales de lesiones orales utilizando diferentes marcadores digitales, también asociada a un sistema móvil para brindar atención odontológica, constituye una excelente herramienta para tratar pacientes que presentan lesiones orales con riesgo potencial de cáncer.

Implementation of a Teledentistry Platform for Dental Emergencies for the Elderly in the Context of the COVID-19 Pandemic in Chile.

Objectives: To develop and implement a "semi-presential" technology platform to support urgent and priority dental care for the elderly in the context of the COVID-19 pandemic among the Chilean population. Methods: A dental mobile clinic was implemented along with the development of a technological platform designed to support emergency and priority dental procedures, including teleconsultation with specialists. Under strict biosafety protocols, dental care was provided in five Chilean regions between February and May 2021. Sociodemographic, medical, and dental data were recorded. Results: A total of 135 patients over sixty years old, with a mean age of 72 years, were treated, 48 males and 87 females were attended between February and May 2021 in five different regions of Chile. 53.3% required immediate or urgent treatment, and 24.4% were derived to specialists from whom 60.6% needed immediate or urgent treatment. 74.3% of teleconsultations were derived to an oral pathology specialist. Conclusion: It was shown that a "semi-presential" technology platform implemented in a mobile dental clinic can help elderly people who are impeded to look for traditional dental assistance during a pandemic.

Collagen quantification in peri-implant soft tissues in human peri-implantitis lesions / Cuantificación de colágeno en tejidos blandos periimplantarios en lesiones de periimplantitis en humanos

SUMMARY: Peri-implantitis is an inflammatory lesion of bacterial etiology characterized by inflammation of the mucosa and bone loss. Chronic inflammation is characterized by neovascularization and collagen neoformation. Mast cells have been shown to participate in the inflammatory process by releasing mediators and proteases such as chymase and tryptase, important in the collagen neoformation process. Although a higher percentage of collagen has been described in periodontal disease, the literature is scarce about the percentage of collagen in peri-implantitis. The aim of this study was to quantify the percentage of collagen fibers present in the peri- implant soft tissue of patients with peri-implantitis lesions. A descriptive observational cross-sectional study was performed. Samples of peri-implant soft tissue were collected from eleven patients with peri-implantitis and then processed by Masson's Trichrome Technique. In microscopic analysis, collagen fibers were observed in all samples, with an average percentage of 39.89 %, standard deviation of 17.02 %, with a minimum value of 8.99 % and a maximum value of 75.65 % density. From these results, it can be concluded that in human peri-implantitis lesions with bone loss greater than 50 %, there is an important percentage of collagen fibers, which is interpreted as connective tissue in a permanent process of reparative response, in the presence of inflammatory infiltrate.

RESUMEN: La periimplantitis es una lesión inflamatoria de etiología bacteriana caracterizada por inflamación de la mucosa y pérdida ósea. La inflamación crónica se caracteriza por neovascularización y neoformación de colágeno. Se ha demostrado que los mastocitos participan en el proceso inflamatorio liberando mediadores y proteasas como quimasa y triptasa, importantes en el proceso de neoformación del colágeno. Aunque se ha descrito un mayor porcentaje de colágeno en la enfermedad periodontal, la literatura sobre el porcentaje de colágeno en la periimplantitis es escasa. El objetivo de este estudio fue cuantificar el porcentaje de fibras de colágeno presentes en el tejido blando periimplantario de pacientes con lesiones de periimplantitis. Se realizó un estudio observacional descriptivo transversal. Se recogieron muestras de tejido blando periimplantario de once pacientes con periimplantitis y luego se procesaron mediante la técnica tricrómica de Masson. En el análisis microscópico, se observaron fibras de colágeno en todas las muestras, con un porcentaje promedio de 39,89 %, desviación estándar de 17,02%, con un valor mínimo de 8,99 % y un valor máximo de 75,65% de densidad. De estos resultados se puede concluir que en las lesiones de periimplantitis humana con pérdida ósea superior al 50 %, existe un porcentaje importante de fibras de colágeno, que se interpreta como tejido conectivo en un proceso permanente de respuesta reparadora, en presencia de infiltrado inflamatorio.

Supramolecular hydrogels based on cellulose for sustained release of therapeutic substances with antimicrobial and wound healing properties.

A multifaceted hydrogel-based formulation was reported. The hydrogel was prepared by crosslinking cellulose and substituted chalcone. Moreover, the formulation was conjugated with carbon nanotubes with the aim of increasing the loading amount of bioactive compounds such as allantoin, dexpanthenol, resveratrol and linezolid. The hydrogel formation was confirmed by swelling tests, FT-IR spectroscopy, thermogravimetric analysis and SEM. The hydrogel showed an improved release rate of therapeutic substances, exhibiting a simultaneous and coordinated release according to the chromatographic studies. The efficacy of drug release was confirmed by wound closure and in vivo wound healing studies that showed promising healing results. The antibacterial assays demonstrated that the sustained release of linezolid tends to be very effective. In conclusion, a multifaceted formulation based on carbon nanotube-containing cellulose-chalcone was developed that can potentially be utilized in treating complex wounds owing to its improved wound healing properties and prevention of potential infections.

Probable Association Between Oral Lichen Planus and presence of Helicobacter Pylori: a Preliminary Study in a Chilean Population / Probable Asociación entre Liquen plano Oral y la presencia de Helicobacter pylori: estudio Preliminar en Chile

ABSTRACT: Oral Lichen planus (OLP) is one of the main inflammatory diseases of the oral mucosa that is considered as a potentially malignant disorder. The exact pathogenesis of OLP remains to be completely understood. However, presence of bacteria has been associated to the inflammatory response observed in OLP. Particularly, Helicobacter pylori a major etiological agent of gastrointestinal inflammatory diseases and risk factor for gastric cancer, has been associated to Lichen planus. Here we studied a group of Chilean patients if there is any association between the presence of Helicobacter pylori and the clinical manifestation of OLP. We found a significant difference between the patients positive for H. pylori and the age of OLP diagnosis, suggesting that oral H. pylori might induce the disease at an earlier age. However, we could not confirm a statistically significance between the presence of the bacteria and OLP.

RESUMEN: Liquen Plano Oral (LPO) es una enfermedad inflamatoria de la mucosa oral considerada como desorden potencialmente maligno. La patogénesis exacta de LPO es desconocida. Sin embargo, se ha asociado la presencia de bacterias como responsables de la inflamación observada en LPO. Particularmente, Helicobacter pylori (H. pylori), agente etiológico principal de enfermedades inflamatorias gastrointestinales y factor de riesgo de cáncer gástrico, ha sido asociado con LPO. Se estudió la posible asociación entre H. pylori y manifestaciones clínicas de LPO en un grupo de pacientes Chilenos. Se encontró diferencia significativa entre los pacientes positivos para H. pylori y la edad de diagnóstico de LPO, sugiriendo que H. pylori podría inducir la enfermedad a temprana edad. Sin embargo, no se pudo confirmar significancia estadística entre la presencia de esta bacteria y la presencia de displasia en LPO.

Film Dressings Based on Hydrogels: Simultaneous and Sustained-Release of Bioactive Compounds with Wound Healing Properties.

This research proposes the rational modeling, synthesis and evaluation of film dressing hydrogels based on polyvinyl alcohol crosslinked with 20 different kinds of dicarboxylic acids. These formulations would allow the sustained release of simultaneous bioactive compounds including allantoin, resveratrol, dexpanthenol and caffeic acid as a multi-target therapy in wound healing. Interaction energy calculations and molecular dynamics simulation studies allowed evaluating the intermolecular affinity of the above bioactive compounds by hydrogels crosslinked with the different dicarboxylic acids. According to the computational results, the hydrogels crosslinked with succinic, aspartic, maleic and malic acids were selected as the best candidates to be synthesized and evaluated experimentally. These four crosslinked hydrogels were prepared and characterized by FTIR, mechanical properties, SEM and equilibrium swelling ratio. The sustained release of the bioactive compounds from the film dressing was investigated in vitro and in vivo. The in vitro results indicate a good release profile for all four analyzed bioactive compounds. More importantly, in vivo experiments suggest that prepared formulations could considerably accelerate the healing rate of artificial wounds in rats. The histological studies show that these formulations help to successfully reconstruct and thicken epidermis during 14 days of wound healing. Moreover, the four film dressings developed and exhibited excellent biocompatibility. In conclusion, the novel film dressings based on hydrogels rationally designed with combinatorial and sustained release therapy could have significant promise as dressing materials for skin wound healing.

Oral diseases: a 14-year experience of a Chilean institution with a systematic review from eight countries

BACKGROUND: Retrospective studies to assess the distribution of oral diseases (ODs) are helpful in estimating the prevalence of oral diagnoses in the population, and thus help in preventive and curative services. Prevalence and frequency data for ODs are available from many countries, but information from Chile is scarce. MATERIAL AND METHODS: This study investigated the frequency of ODs in a Chilean population. For this, we included all patients treated at the University of Talca (UTALCA, Chile) between 2001 and 2014. Patient characteristics were retrieved from medical files. To contextualize our results, we conducted a systematic review (SystRev) using Publish or Perish software (PoP), Google Scholar and MEDLINE/PubMed. RESULTS: One hundred sixty-six ODs were diagnosed, and the most prevalent groups were soft tissue tumours, epithelial pathology and salivary gland pathology. Individually, irritation fibroma, oral lichen planus (OLP) and mucocele were the most common diagnoses. ODs frequently affected unspecified parts of the mouth (including cheek, vestibule and retromolar area), gum, lips, tongue and palate. In the SystRev, the more studied diagnoses were leukoplakia, OLP and recurrent aphthous stomatitis; prevalent lesions included Fordyce's spots, recurrent aphthous stomatitis and fissured tongue. Chilean patients and SistRev shared almost all ODs. CONCLUSIONS: The results reflect ODs diagnosed in a specialized service of oral pathology and medicine in Chile and will allow the establishment of preventive/curative policies, adequate health services and dentistry curriculum

Expresión de TGFß1 por fibroblastos de mucosa oral expuestos a radiación ultravioleta B / TGF1 expression by oral mucosa fibroblasts exposed to ultraviolet ß1 radiation

El objetivo de este estudio fue evaluar el efecto de la radiación ultravioleta (UV) B sobre la expresión del factor de crecimiento transformante (TGF) ß1 por fibroblastos de mucosa oral, con el objetivo de dilucidar si este tipo celular puede contribuir a la expresión de TGFß1 en bermellón labial sobreexpuesto a la radiación UV. Se obtuvieron cultivos primarios de fibroblastos desde explantes de mucosa bucal, los que fueron irradiados con una dosis única de luz UVB (60 mJ/cm2). Se midió proliferación celular con el método MTT, y la expresión de TGFß1, a nivel de ARN mensajero (normalizado a GAPDH) por RT-PCR y a nivel de proteína mediante inmunofluorescencia. Se observó una disminución de la proliferación celular de los fibroblastos de mucosa oral a las 24 hrs post-irradiación en relación a los fibroblastos no irradiados (P<0,05, Mann Whitney). No se encontraron diferencias entre los fibroblastos control y los irradiados en la expresión de TGFß-1 ni a nivel de mensajero (0,5 y 6 h post-irradiación), ni de proteína (24 h post-irradiación). Los resultados sugieren que los fibroblastos de mucosa oral presentan una disminución de su proliferación en respuesta a una dosis única de radiación UVB, sin que se afecte la expresión de TGFß-1, la que fue similar a los fibroblastos no irradiados. Esto sugiere que los fibroblastos contribuirían a la producción de TGFß-1 en respuesta a la exposición crónica a UVB del bermellón labial.

The objective of this study was to characterize the effect of Ultraviolet (UV) B irradiation on the expression of transforming growth factor (TGF) ß1 by oral mucosa fibroblasts, in order to assess if these cells contribute to the production of TGFß-1 in UV-irradiated lip vermillion. Primary cultures of fibroblasts were obtained from oral mucosa explants, and were irradiated with a single dose of UVB light (60 mJ/cm2). The effects of UVB radiation on cell proliferation was evaluated by the MTT method. The effects of UVB on the expression of TGF-ß1 was analyzed by RT-PCR (normalized to GAPDH) and by immunofluorescence. The results showed a decrease in the proliferation of UVB-irradiated fibroblasts as compared to controls at 24h post-irradiation (p<0.05). No variations in the expression of TGFß1, both at the mRNA and protein level, were observed between control and UVB-irradiated fibroblasts during the first 24 h after irradiation. Oral mucosa fibroblasts have reduced proliferation in response to a single dose of UVB, but their expression of TGFß1 was not affected. This suggests that oral mucosa fibroblasts may contribute to the production of TGFß1 in the lip vermillion independent of UVB exposure.

Spontaneous remission of eosinophilic granuloma of the maxilla after incisional biopsy: a case report.

BACKGROUND: Langerhans cell histiocytosis (LCH), previously known as Histiocytosis X, is an infrequent disease that congregates a wide spectrum of clinical presentations with variable systemic involvement. Unification of these diseases under only one category is based on the almost identical histopathologic features of the lesions, but the etiology and proper approach for each presentation remains controversial. The localized alternative of Langerhans cell histiocytosis (LLCH), known as Eosinophilic Granuloma (EG) of bone, is the predominant clinical presentation of LCH. The maxilla is involved in 1 % of the head and neck region cases, representing an uncommon condition in this area. CASE PRESENTATION: In this clinical case report, it is described a case of a 16-year-old male patient with an asymptomatic osteolytic lesion at first upper left molar apical level, a finding detected on control radiographic images was reported as "Monostotic Eosinophilic granuloma of the maxillary bone", which was later confirmed through an incisional biopsy. A surgical excision was initially planned, but finally it was not performed due to a spontaneous healing of the lesion after the incisional biopsy. CONCLUSIONS: The presented case supports a conservative approach in the management of solitary EG of maxillary and mandibular bone lesions and even supports an expectant attitude in the course of treatment given the possibility of a spontaneous regression after the biopsy, especially in small lesions.

Virus papiloma humano en cáncer oral y orofaríngeo: revisión de la literatura / Human papilloma virus in oral and oropharyngeal cancer: review of the literature

Estudios recientes demuestran una realidad prácticamente ineludible que manifiesta que el Virus Papiloma Humano (VPH) puede estar asociado al desarrollo del Carcinoma de Células Escamosas en cavidad oral y orofarínge. Desde el descubrimiento en 1974 por parte de zur Hausen et al., quienes ayudaron a definir el mecanismo por medio del cual el VPH provoca la transformación del queratinocito normal a un estado maligno, han sido numerosos los estudios que han descrito la presencia del VPH en carcinomas de cabeza y cuello, específicamente en cavidad oral y orofarínge. La detección del virus en estos carcinomas podría tener implicaciones clínicas importantes en el pronóstico y tratamiento de estos tumores, con resultados más favorables para el paciente; así mismo, justificar planes de prevención orientados al diagnóstico temprano y a la protección específica contra el VPH. Actualmente están en desarrollo terapias experimentales mínimamente invasivas que potencian el sistema inmunitario para atacar estos tumores, sin embargo, aún no están aprobadas para su uso general. En Chile todavía no existen estudios que describan la situación actual del VPH con respecto al Carcinoma de Células Escamosas en cavidad oral y orofarínge que pudieran orientar al sistema de salud con respecto a la prevención y tratamiento de este tipo de cáncer. En esta revisión presentamos los principales aspectos que relacionan al virus con este tipo de carcinoma. Se revisaron artículos indexados en inglés (Pubmed, Scopus, Cochrane Library, Google Scholar) y español (SciELO, Google Scholar), con el objetivo de brindar al Odontólogo general y especialistas una información actualizada sobre este tema, tanto desde su epidemiología como desde los mecanismos de acción carcinogénica del virus, técnicas de diagnóstico avanzadas, además, formas de prevención y estado del arte en materia de tratamiento.

Recent studies indicate what has become a nearly inescapable reality in that Human Papilloma Virus can be associated to the development of Oral and Oropharyngeal Squamous Cell Carcinoma. Since the discovery of zur Hausen et al. that helped define the mechanism by which HPV causes normal keratinocyte transformation to a malignant state, there have been numerous studies that have described the presence of HPV in head and neck carcinomas, specifically in oral cavity and oropharynx. The detection of the virus in these carcinomas may have important clinical implications in the prognosis and treatment of these tumors with more favorable patient outcomes; likewise, justify prevention plans aimed at early diagnosis and specific protection against HPV. Currently minimally invasive experimental therapies that boost the immune system to attack these tumors are in development, however, they are not yet approved for general use. In Chile there are no studies that describe the current situation with regard to HPV Squamous Cell Carcinoma in oral cavity and oropharynx that may guide the health system regarding the prevention and treatment of this cancer. In this review we present the principal aspects that associate the virus with this type of oral and oropharyngeal carcinoma. We reviewed indexed articles in English (Pubmed, Scopus, Cochrane Library, Google Scholar) and Spanish (SciELO, Google Scholar), with the objective to provide Dental Surgeons and specialists the most updated information about this subject. The review was developed considering the epidemiology as well as the carcinogenic mechanisms of the virus, advanced diagnostic techniques, ways of prevention and state of the art in treatment matters.

Análisis histopatológico de casos de cáncer oral en instituciones de las regiones chilenas del Maule y Bío-Bío entre los años 2001-2011 / Histopathological analysis of oral cancer cases in health institutions of Maule and Bío-Bío Chilean regions between the years 2001-2011

El carcinoma oral de células escamosas (COCE) es una neoplasia epitelial invasiva con diferentes grados de diferenciación y una propensión a metástasis. La evidencia acumulada para el COCE en Chile es escasa, y más aún para la séptima región del Maule y octava región del Bío-Bío, por lo tanto el motivo de esta investigación es presentar un análisis histopatológico de pacientes diagnosticados de COCE que aporte al conocimiento de la realidad local y nacional. Se realizó un estudio observacional retrospectivo, que incluyó a una muestra por conveniencia (COCE n = 33) de instituciones de la séptima y octava región de Chile. La edad media de los pacientes fue de 65 años. La ubicación anatómica más frecuente para el COCE fueron los labios (36,4 por ciento), seguido de la lengua (27,3 por ciento) y el piso de la boca (9,1 por ciento). Predominaron los COCE moderadamente diferenciados (51,5 por ciento), con un patrón de invasión tumoral infiltrante (81,8 por ciento) y una respuesta inmune moderada/marcada (75,8 por ciento). En estas regiones el COCE afecta principalmente a personas mayores, se ubica en una zona anatómica fácilmente accesible para el examen, lo que debería permitir el diagnóstico en etapas iniciales. Son necesarios profesionales con conocimientos de posgrado o especialización en patología y medicina oral en los centros de atención pública.

Squamous cell carcinoma of the oral cavity (OSCC) is an invasive epithelial neoplasm with varying degrees of differentiation and propensity to metastasise. Chilean evidence for OSCC is scarce, and even more so for the Seventh (Maule) and Eighth (Bío-Bío) regions. Hence, the present study is carried out to evaluate the histopathological features of OSCC patients to contribute to local and national knowledge. A retrospective observational study was conducted on a convenience sample (n = 33) from health care institutions of Seventh and Eighth Chilean regions. The mean age of patients was 65 years. The most common OSCC anatomical locations were lips (36.4 percent), followed by the tongue (27.3 percent), and the floor of the mouth (9.1 percent). Moderately differentiated OSCC predominated (51.5 percent), with a pattern of infiltrating tumour invasion (81.8 percent) and a moderate/strong immune response (75.8 percent). In these Chilean regions, OSCC mainly affects older people and is located in an easily accessible area for anatomical examination, which should allow early diagnosis. Professionals with post-graduate knowledge or expertise in Pathology and Oral Medicine are needed in public health care centres.

Clinicopathological and immunohistochemical evaluation of oral and oropharyngeal squamous cell carcinoma in Chilean population.

In oral and oropharyngeal squamous cell carcinoma (OCSCC and OPSCC) exist an association between clinical and histopathological parameters with cell proliferation, basal lamina, connective tissue degradation and surrounding stroma markers. We evaluated these associations in Chilean patients. A convenience sample of 37 cases of OCSCC (n=16) and OPSCC (n=21) was analyzed clinically (TNM, clinical stage) and histologically (WHO grade of differentiation, pattern of tumor invasion). We assessed the expression of p53, Ki67, HOXA1, HOXB7, type IV collagen (ColIV) and carcinoma-associated fibroblast (α-SMA-positive cells). Additionally we conducted a univariate/bivariate analysis to assess the relationship of these variables with survival rates. Males were mostly affected (56.2% OCSCC, 76.2% OPSCC). Patients were mainly diagnosed at III/IV clinical stages (68.8% OCSCC, 90.5% OPSCC) with a predominantly infiltrative pattern invasion (62.9% OCSCC, 57.1% OPSCC). Significant association between regional lymph nodes (N) and clinical stage with OCSCC-HOXB7 expression (Chi-Square test P < 0.05) was observed. In OPSCC a statistically significant association exists between p53, Ki67 with gender (Chi-Square test P < 0.05). In OCSCC and OPSCC was statistically significant association between ki67 with HOXA1, HOXB7, and between these last two antigens (Pearson's Correlation test P < 0.05). Furthermore OPSCC-p53 showed significant correlation when it was compared with α-SMA (Kendall's Tau-c test P < 0.05). Only OCSCC-pattern invasion and OPSCC-primary tumor (T) pattern resulted associated with survival at the end of the follow up period (Chi-Square Likelihood Ratio, P < 0.05). Clinical, histological and immunohistochemical features are similar to seen in other countries. Cancer proliferation markers were associated strongly from each other. Our sample highlights prognostic value of T and pattern of invasion, but the conclusions may be limited and should be considered with caution (small sample). Many cases were diagnosed in the advanced stages of the disease, which suggests that the diagnosis of OCSCC and OPSCC is made late.

Histological and molecular aspects of oral squamous cell carcinoma (Review).

Oral squamous cell carcinoma (OSCC) represents 95% of all forms of head and neck cancer, and over the last decade its incidence has increased by 50%. Oral carcinogenesis is a multistage process, which simultaneously involves precancerous lesions, invasion and metastasis. Degradation of the cell cycle and the proliferation of malignant cells results in the loss of control mechanisms that ensure the normal function of tissues. The aim of the current review is to present the histopathological features of OSCC, including potentially malignant changes, the international classification of tumors, the tumor invasion front and tumor biomarkers (Ki-67, p53, homeobox genes and collagen type IV), as well as the tumor microenvironment and function of cancer-associated fibroblasts in the most common type of oral cancer that is encountered by dental surgeons. In OSCC, associations have been identified between the proliferation, basal lamina degradation and connective tissue modulation. Therefore, the comparison of these factors with the survival time of OSCC patients from the histopathological diagnosis is of interest.