Comparative clinicopathological study of the main anatomic locations of oral squamous cell carcinoma.

OBJECTIVE: To analyze the clinicopathological and evolutionary profile of the main locations of oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: This is a retrospective study on 133 patients treated for OSCC. The group was composed of 48 women and 85 men, with a mean age 63.9 ± 12.73 years. Most cases involved the lingual border of tongue (63), followed by the gingiva (36) and the floor of mouth (34). A comparative analysis was performed using multinomial regression. RESULTS: There were significant differences regarding age, sex, tobacco and alcohol consumption, liver pathology, oral potentially malignant disorders, and bone and perineural invasion. In multivariate regression, tobacco consumption, and bone invasion remained significant. There were no significant differences in relation to prognosis. CONCLUSION: The location of OSCC is an important factor in the clinicopathological assessment of this neoplasm. The main locations of OSCC show differential etiopathogenic and clinicopathological aspects. Tobacco consumption has a great relevance in the floor of mouth; nonetheless, it is less important in the tongue border and the gum, which suggests other pathogenic factors. It is necessary to consider the anatomical location of OSCC in preventive protocols, with the aim of reducing its high mortality.

Clinical practice guideline of the spanish society of oral surgery for oral surgery in patients with coagulation disorders / Guía de práctica clínica de la sociedad española de cirugía bucal para cirugía oral en pacientes con trastornos de la coagulación

Background: The number of patients treated with coagulation disorders, and more specifically with anticoagulanttherapy, has increased worldwide in recent years due to increased life expectancy in developed countries. Theprotocols for managing this type of patient in oral surgery has varied over recent years, especially after the appear-ance of new direct-acting oral anticoagulants (DOACs). The assessment of risk of bleeding in this type of patientwhen undergoing a surgical procedure continues to be a controversial issue for patients, dentists and general prac-titioners. The objective of this document is to offer recommendations, based on evidence, for decision making forpatients with coagulopathies who require dental surgical intervention. Material and Methods: Based on the indications of the “Preparation of Clinical Practice guidelines in the NationalHealth System. Methodological manual”, we gathered a group of experts who agreed on 15 PICO questions basedon managing patients with coagulation disorders in dental surgical procedures, such as fitting of implants or dentalextractions.Results: The 15 PICO questions were answered based on the available evidence, being limited in most cases due tothe lack of a control group. Two of the PICO questions were answered by the experts with a grade C recommendation,while the rest were answered with grade D.Conclusions: The results of this review highlight the need to undertake well designed clinical trials with controlgroups and with a representative sample size.(AU)

Importance of the vaporization margin during CO2 laser treatment of oral leukoplakia: A survival study.

OBJECTIVES: The main purpose of this study was to assess the response of oral leukoplakia to CO2 laser vaporization treatment, as well as determining possible factors that may affect recurrence of lesions. MATERIALS AND METHODS: A retrospective study was conducted, in which the medical records of patients who had been clinically and histologically diagnosed with oral leukoplakia and treated with CO2 laser between 1996 and 2019 at the Oral Medicine Teaching Unit of the Faculty of Dentistry of the University of Santiago de Compostela were reviewed. RESULTS: Fifty-eight patients were included: 36 female and 22 male subjects, with a mean age of 63.7 years old (SD ±13.1). The average follow-up time was 57.5 months (SD ±57.9). A relapse rate of 52.6% was determined. Of all the studied variables, the margin was the only one for which a statistically significant association with recurrence of lesions was demonstrated (p < 0.05). CONCLUSION: The vaporization of lesions using CO2 laser with a safety margin of at least 3 mm from the clinical limits of OL is a key factor in preventing recurrence.

A new morphologic classification of the alveolar ridge after distraction osteogenesis in human patients. A 17 years retrospective case series study / Una nueva clasificación morfológica de la cresta alveolar después de la distracción osteogénesis en pacientes humanos. Un estudio de serie de casos retrospectivo de 17 años

Background: To perform a morphologic classification based on the results of bone augmentation after a distractionosteogenesis.Material and Methods: Thirty-four (34) patients (24 women and 10 men; mean age, 47.1 years (SD=9.5); age range,23 to 62 years) underwent a total of 42 alveolar ridge distractions before the placement of a total of 89 dentalimplants. Ridge bone morphology was evaluated as the main ordinal variable. Chi-squared, Kruskal-Wallis andANOVA one-way test were used.Results: Category I (30.95%): consisted of wide alveolar rim and no bone defects Category II (28.57%): widealveolar rim, lateral bone surface concavity. Category III (23.81%): narrow alveolar rim, lateral bone surface con-cavity. Category IV (2.38 %): distraction transport segment forming a bridge, without bone formed beneath andrequiring guided bone regeneration. Category V (9.52%): return of the transport segment to its initial position dueto the reverse rotation of the distractor screw. Category VI (4.76 %): distraction transport segment completely lost.Subcategory D (28.57%), consisted of lingual deviation of the distraction axis, occurring in any of the categories Ito IV. More men (76.9 %) presented with category I (p<0.001). The use of the chisel resulted mainly in categories I and II (69.4 %) (p<0.001). GBR was only required in 23.1 % of the cases in Category I (p=0.011). The bone heightachieved decreases as the category increases, due to the accompanying osteogenic limitations (p<0.001). The im-plants placed in category I were longer 11.5 ± 0.9 mm (CI95% 10.9-11.9 mm) compared to those placed in categoryIII with a length of 10.4 ± 1.5 mm (CI95% 9.5-11.4 mm) (p=0.035).Conclusions: The alveolar ridge after distraction osteogenesis could be divided into six morphologic categorieswhich provide a useful basis for decision-making regarding implant placement.(AU)

Efficacy of different formulations of nystatin in an experimental model of oral candidiasis in sialoadenectomized rats.

BACKGROUND/PURPOSE: Oral candidiasis is the most common fungal infection of the oral cavity and has become a focus of attention in recent years because of its association with highly topical immunosuppressive conditions. The aims of this study were to determine the value of microbiological, clinical and histological parameters of Candida albicans colonisation of the dorsal tongue surface as indicators of disease severity, and to evaluate therapeutic response to different formulations of nystatin. MATERIALS AND METHODS: We used 84 males, 2-month-old Sprague-Dawley sialoadenectomized rats. Different formulations of nystatin were used to evaluate the therapeutic response. The animals were randomized to 2 groups with each of 42 animals and received the experimental treatments from day 17-22. RESULTS: 100% of the rats showed evidence of infection. At 5 and 10 days of starting treatment with nystatin + chitosan, and at 10 days of starting nystatin + orabase, the number of animals with positive dorsal tongue culture decreased significantly (p < 0.05), acting the Nystatin + chitosan more rapidly against Candida. In the control group, the percentage of normal papillae on day 22 and 27 was 83.33% (SD = 1.50) and 79.08% (SD = 2.30), respectively. Significant differences were observed in the mean O'Grady score at 5 and 10 days (p < 0.0001). CONCLUSION: The model has been shown to be effective in inducing infection, and that the combination of nystatin and chitosan yielded the best therapeutic outcomes at both 5 and 10 days after infection.

p27Kip1 expression as a prognostic marker for squamous cell carcinoma of the head and neck.

Regulation of the cell cycle is essential for carcinogenesis. The cell cycle is controlled by cyclin-dependent kinases (CDKs), which are upregulated by cyclins and downregulated by CDK inhibitors (CDKIs). Decreased p27Kip1 expression has been associated with survival rate, tumor size, histological differentiation and the presence of lymph node metastasis in patients with various types of cancer. The aim of the current study is to provide a literature review on the association between p27Kip1 expression and the clinical and pathological aspects of head and neck squamous cell carcinoma (HNSCC), and the expression of other CDKIs of the Cip/Kip family and cyclins. Throughout the literature, different methodologies were used to determine the immunohistochemical expression of p27Kip1; thus, results concerning p27Kip1 expression in HNSCC vary widely. However, it has now been confirmed that p27Kip1 is underexpressed in SCC cells. p27 may be a promising marker for determining the prognosis of HNSCC, despite the marked variability of the results obtained. An association between p27 expression and survival rate, time to recurrence and tumor stage has been observed. Based on the information currently available, it is premature to recommend the analysis of p27Kip1 expression in guiding HNSCC treatment planning. However, although relatively unstudied, the correlation between p27Kip1 expression and other tumor suppressor genes may turn out to be important in determining the prognosis of HNSCC. Further prospective studies utilizing standardized laboratory methodologies and statistics that facilitate meta-analyses are required to confirm this proposal.

Dental implants placed on bone subjected to vertical alveolar distraction show the same performance as those placed on primitive bone

Introduction: Vertical osteogenic alveolar distraction (VOAD) allows for the augmentation of the alveolar ridge for the placement of dental implants in atrophic alveolar ridges. The goal of this paper is to assess long-term peri-implant bone resorption in implants placed on bones subjected to VOAD, comparing it with a group of patients who had implants placed directly on the alveolar bone without previous bone regeneration. Material and Methods: We conducted a follow-up study on 32 patients who were divided into two groups: The Distraction Group (14 patients), and the Distraction-Free Group (18 patients), who received a total of 100 implants. Peri-implant bone loss was measured by means of panoramic X-rays, at the time of loading and one year later, and in 35 implants of each group after 3 years of functional loading. Results: The peri-implant bone resorption (PBR) average observed in the Distraction Group at the time of prosthetic placement is higher (0.50±0.09 mm) than in the Distraction-Free Group (0.25±0.06 mm), showing statistically significant results (p=0.047). PBR levels 1 year after loading were the same for both groups (0.66 mm). At 3 years, they were higher in the Distraction Group (1.03 ± 0.22 mm vs. 0.68 ± 0.08 mm) (AU)

Dental implants placed on bone subjected to vertical alveolar distraction show the same performance as those placed on primitive bone.

INTRODUCTION: Vertical osteogenic alveolar distraction (VOAD) allows for the augmentation of the alveolar ridge for the placement of dental implants in atrophic alveolar ridges. The goal of this paper is to assess long-term peri-implant bone resorption in implants placed on bones subjected to VOAD, comparing it with a group of patients who had implants placed directly on the alveolar bone without previous bone regeneration. MATERIAL AND METHODS: We conducted a follow-up study on 32 patients who were divided into two groups: The Distraction Group (14 patients), and the Distraction-Free Group (18 patients), who received a total of 100 implants. Peri-implant bone loss was measured by means of panoramic X-rays, at the time of loading and one year later, and in 35 implants of each group after 3 years of functional loading. RESULTS: The peri-implant bone resorption (PBR) average observed in the Distraction Group at the time of prosthetic placement is higher (0.50 ± 0.09 mm) than in the Distraction-Free Group (0.25 ± 0.06 mm), showing statistically significant results (p=0.047). PBR levels 1 year after loading were the same for both groups (0.66 mm). At 3 years, they were higher in the Distraction Group (1.03 ± 0.22 mm vs. 0.68 ± 0.08 mm).

Beta-adrenergic receptors in cancer: therapeutic implications.

The beta-adrenergic receptors transduce catecholamine signals to the G protein, which through a cascade of chemical reactions in cells generates highly specific parallel signals. The beta2-adrenergic receptor (ADRB2) is the most involved in the carcinogenic processes. Previous studies have determined the relationship of ADRB2 with various aspects related to cancer. Basically, it seems to be related with cell proliferation and apoptosis, chemotaxis, development of metastasis and tumor growth, and angiogenesis. The purpose of this review is to update the implications of these receptors in the pathogenesis of cancer and study the possible application of agonist drugs and/or antagonists in antitumor therapy.

Measurement of ATP6V1C1 expression in brush cytology samples as a diagnostic and prognostic marker in oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral cavity. Brush cytology has reemerged as a molecular tool for diagnosing this cancer. ATP6V1C1, one of the main genes regulating V-ATPase activity, has been implicated in metastasis and multiple drug resistance. The aim of this study was to measure ATP6V1C1 expression levels in OSCC and to evaluate the value of this test in the diagnosis and prognosis of OSCC. RESULTS: The differences in ATP6V1C1 expression between patients and controls were statistically significant (Mann-Whitney U test = 26, p < 0.001). Receiver operating characteristic (ROC) curve analysis showed an area under the curve of 0.9476, with the following diagnostic indices: sensitivity, 81.25%, specificity, 93.75%; accuracy, 87.50%; positive predictive value, 92.86%; negative predictive value, 83.33%; positive likelihood ratio, 30; and negative likelihood ratio, 0.06. MATERIAL AND METHODS: Patients with OSCC and a control group of healthy individuals were studied. The clinical and demographic variables analyzed included age, sex, smoking, tumor location and tumor stage. Brush cytology samples were obtained using a cytology brush and analyzed by real-time quantitative polymerase chain reaction for ATP6V1C1 expression. CONCLUSIONS: It was confirmed that ATP6V1C1 levels were significantly higher in patients with OSCC than in healthy controls, with expression increasing with higher tumor stage. ROC analysis showed that the measurement of ATP6V1C1 expression levels is a highly sensitive and specific diagnostic method.

Multidrug resistance in oral squamous cell carcinoma: The role of vacuolar ATPases.

Resistance to chemotherapy agents is the main reason for treatment failure in patients with cancer. Multidrug resistance (MDR) is the primary mechanism that leads to the acquisition of the multiresistant phenotype through the overexpression of drug efflux transporters such as the P-glycoprotein (Pgp), encoded by the MDR1 gene, at the plasma membrane. Other molecules that have been implicated in drug resistance include multidrug resistance-associated proteins, glutathione S-transferase-pi, and DNA topoisomerase II. These molecules, however, cannot fully explain MDR in oral squamous cell carcinoma. Vacuolar ATPase (V-ATPase), which is largely responsible for regulating acidity in the microenvironment of solid tumors (and hence interfering with the absorption of chemotherapy drugs), seems to be the most important molecule involved in MDR in such tumors. Specific V-ATPase inhibitors, thus, may be useful, not only as coadjuvants in antitumor treatments but also as a mechanism for controlling resistance to antitumor drugs.

RANK/RANKL/OPG role in distraction osteogenesis.

Distraction osteogenesis is a fundamental pillar for craniomaxillofacial reconstruction processes. Nonetheless, although the clinical, biomechanical, and histologic changes associated with distraction osteogenesis have been widely described, this is not the case with the molecular mechanisms that regulate bone synthesis in the interfragmentary gap resulting from the gradual separation of bone segments. Recent studies have attributed a decisive role to the RANK/RANKL/OPG system in regulating bone metabolism and osteoclastogenesis. Receptor activator of nuclear factor kappa beta (RANK), belonging to the tumor necrosis factor superfamily, is present in the osteoclasts. It promotes osteoclastogenesis when it binds to RANK ligand (RANKL), which is produced by the osteoblasts and other stromal cells. Osteoprotegerin (OPG) acts as a decoy receptor by binding to RANKL and preventing RANK signaling. Osteoclast activation is thus blocked and apoptosis induced. The aim of this review is to analyze the influence of the RANK/RANKL/OPG system on the bone healing and remodeling processes that occur in distraction osteogenesis, with a view to possibly developing molecular mechanisms that stimulate bone regeneration and inhibit resorption, thereby improving the clinical outcome for distraction osteogenesis.

V-ATPase inhibitors and implication in cancer treatment.

Acidity is one of the main features of the tumors. The V-ATPase is the primary responsible for the control of tumor microenvironment by proton extrusion to the extracellular medium. The acid environment favors tissue damage, activation of destructive enzymes in the extracellular matrix, the acquisition of metastatic cell phenotypes as well as increasing the destructive capacity. The application of specific inhibitors of V-ATPases, can decrease the acidity of tumor and may allow the reduction of tumor metastasis, acting on the survival of tumor cells and prevent the phenomena of chemoresistance. Among the most important inhibitors can be distinguished benzolactone enamides (salicylihalamide), lobatamide A and B, apicularen, indolyls, oximidine, macrolactone archazolid, lobatamide C, and cruentaren. The latest generation of inhibitors includes NiK12192, FR202126, and PPI SB 242784. The purpose of this paper is to describe the latest advances in the field of V-ATPase inhibitors, describe further developments related to the classic inhibitors, and discuss new potential applications of these drugs in cancer treatment.

Pederson scale fails to predict how difficult it will be to extract lower third molars.

We report a consecutive series of 105 extractions of impacted lower third molars, in each of which operative difficulty was predicted preoperatively using the Pederson scale (radiographic appearance of the anatomical position of the lower third molar), and postoperative difficulty was scored with a modified version of the Parant scale (operative manoeuvres that were needed for extraction of the third molar). Preoperative classification as "difficult" on the Pederson scale was not an accurate predictor of true difficulty (postoperative classification as "difficult" on the modified Parant scale). There was no significant association between the Pederson score and duration of operation, but high Parant scores were significantly associated with longer operations. We suggest that scales for the prediction of operative difficulty in the extraction of impacted lower third molars should take into account factors other than the anatomical position of the tooth.

Gene expression profile in oral squamous cell carcinoma: a pilot study.

PURPOSE: To study the gene expression profile of oral squamous cell carcinomas. MATERIALS AND METHODS: Gene expression profile was investigated in oral squamous cell carcinomas in 5 patients using the Atlas Glass Human 3.8 I Microarray (which detects cDNA obtained from cellular total RNA) (Clontech Laboratories, Palo Alto, CA). Data were normalized by the LOWESS method. Statistical significances of deviations from a 1:1 ratio were evaluated by t tests, with P<.05. RESULTS: Of the 3,757 genes analyzed, 322 (8.6%) were significantly overexpressed in tumoral tissue with respect to normal tissue, while 104 (2.8%) were significantly underexpressed. The affected genes fell into a wide range of functional categories. CONCLUSION: We consider that cDNA microarrays are of clear value for investigating the biology of these tumors, and that this technology may help in the molecular classification of oral squamous cell carcinomas and in the identification of targets for gene therapy.