TMJ arthroscopy with hyaluronic acid: A 12-month randomized clinical trial.

OBJECTIVES: To determine the effects of hyaluronic acid (HA) as an adjunct to temporomandibular joint (TMJ) arthroscopy, relative to standard TMJ arthroscopy, in Wilkes stage-III and stage-IV patients. METHODS: A randomized clinical trial design was utilized (ClinicalTrials.gov NCT04110587). 51 patients were allocated to a TMJ arthroscopy (n = 25) or a TMJ arthroscopy plus HA (n = 26) group. Visual analog scale joint pain scores, maximum mouth opening (MMO), and muscle pain were measured at baseline, and at 3, 6, 9, and 12 months. Disk position on magnetic resonance imaging was evaluated at baseline and 12 months. Oral health-related quality of life (OHRQoL) was assessed at baseline, and at 6 and 12 months. RESULTS: No group differences were observed in clinical or radiographic measurements (p ≥ .05). The results do not indicate any benefit of HA as an adjuvant therapy to arthroscopy during follow-up months 3-12. TMJ arthroscopy improved OHRQoL at 6 and 12 months (Oral Health Impact Profile-14 questionnaire scores of -14.59 and -14.27, 95% confidence intervals = -17.55 to -11.63 and -17.27 to -11.27) respectively, as well as pain and MMO, at all follow-up time points (p < .001). CONCLUSIONS: A beneficial effect of HA injection during TMJ arthroscopy after the 3-month follow-up was not observed.

A comparative study of the expression of cyclin D1, COX-2, and KI-67 in odontogenic keratocyst vs. ameloblastoma vs. orthokeratinized odontogenic cyst.

BACKGROUND: Odontogenic keratocysts (OKCs) and orthokeratinized odontogenic Cysts (OOCs) are distinct clinicopathological entities. OKC appears to behave in a way more similar to that of a neoplasm, such as ameloblastoma (AB). The aim of this study is to compare the influence of Ki-67, Cyclin D1 and COX-2 in the diagnosis and pathogenesis of OKC, OOC and AB. MATERIALS AND METHODS: A cross-sectional observational study of 41 samples was organized into 3 groups: (1) OKC n=22; (2) AB n=13 and (3) OOC n=6. Paraffin blocks were sectioned and stained with hematoxylin and eosin (H&E). Immunohistochemical study using Bond Polymer Refine Red Detection Kit, Leica, Wetzlar, Germany, was performed for the following antibodies: Ki-67, Cyclin D1 and COX-2. Double blind immunostaining was quantified subjectively. Staining: nuclear or cytoplasmic; nuclear (Ki-67 and Cyclin D1>5% positive) and cytoplasmic (COX-2; 1; 1-30 cytoplasm: 2; 31-60 cytoplasm; 3; 61-100 cytoplasm). Considering positive stained 61-100 cytoplasms. RESULTS: The expression of Ki-67 was higher in the OKC group than in the AB group (p<0.05). Cyclin D1 showed a higher expression in OKC vs. OOC and OKC vs. AB (p<0.05). Finally, expression of COX-2 was higher in OKC vs AB (p<0.05). CONCLUSIONS: COX-2, Ki-67 and Cyclin D1 show statistically significant differences between the groups, suggesting that they could be useful tools in the differential diagnosis between OKCs and OOC and a predictive indicator for their biologic behaviour. The higher expressions of these 3 markers of OKC vs AB highlight once more the aggressive behaviour of this now re-considered cystic lesion. These markers could prove useful in the choice of more aggressive surgical treatment in OKCs as their behaviour appears to be similar to that of a neoplasm.

Analysis of new diagnostic methods in suspicious lesions of the oral mucosa.

OBJECTIVE: The objective of this study was to analyse publications related to examination techniques that might improve the visualisation of suspicious lesions of the oral mucosa (ViziLite system and VELscope system) or that might facilitate the cytological identification of suspicious lesions (OralCDx). METHODS: A literature search was performed, using the PubMed database and the key words "brush biopsy", "OralCDx", "ViziLite" and "Velscope", limiting the search to papers in English or Spanish published from 2002 to 2008. RESULTS: According to the results of studies identified, the ViziLite system has a sensitivity of 100% and specificity ranging from 0-14.2%, the VELscope system has a sensitivity of 98-100% and specificity of 94-100% and the Oral CDx system has a sensitivity of 71.4-100% and specificity of 32-100%. CONCLUSION: Clinical examination and histopathological confirmation with biopsy remain the gold standard for the detection of oral cancer. More randomised controlled studies are needed to confirm the positive cost-benefit relationship and the true usefulness of these "new diagnostic methods" in oral mucosal pathology.

Host defence mechanisms against bacterial aggression in periodontal disease: Basic mechanisms.

Periodontal diseases are complex bacteria-induced infections characterised by an inflammatory host response to plaque microbiota and their by-products. Most of these microorganisms have virulence factors capable of causing massive tissue destruction both directly, through tissue invasion and the production of harmful substances, or indirectly, by activation of host defense mechanisms, creating an inflammatory infiltrate of potent catabolic activity that can interfere with normal host defense mechanisms. In response to the aggression, host defense mechanisms activate innate and adaptive immune responses. Our aim is to offer a general overview of the main mechanisms involved in the host response to bacterial aggression in periodontitis, such as lipopolysaccharide receptor CD14, complement system, polymorphonuclear neutrophils, antibodies and immunoglobulins.

Problem-based learning versus lectures: comparison of academic results and time devoted by teachers in a course on Dentistry in Special Patients.

OBJECTIVES: Problem-Based Learning (PBL) is a teaching-learning technique centred on the complete development of the student. It has been successfully implemented in several universities, notably in the health sciences. The process of creating the European Higher Education Area, initiated in Bologna, encourages European universities to use new methodologies in the teaching-learning process, including PBL. Our objectives were to analyze the results obtained by using PBL with fifth-year Dentistry students. STUDY DESIGN: Comparison of academic results between students receiving lectures and PBL participants, and assessment of differences between them in the time devoted to tasks by students and teachers. RESULTS: PBL participants obtained higher grades compared to those receiving lectures only (p<0.05). The two student groups devoted the same amount of time to this subject but the time distribution of tasks was very different, with PBL students spending more time on group work and analysis of the literature. The teachers devoted much more time to the PBL group. CONCLUSIONS: PBL is a teaching-learning methodology that improves student academic results. PBL diverts student time to more complex tasks but requires a greater commitment from the teachers.

Oral pulse granuloma and oral pulse granuloma associated with odontogenic keratocyst: Two clinical cases and a review of the literature.

Two cases of oral pulse granuloma (OPG) or vegetable granuloma (VG) are presented, one of which was concomitant with an odontogenic keratocyst (OKC), which is an unusual finding. OKC is characterized by the presence of hyaline rings which include vessels, giant cells, other inflammatory cells and collagen fibres. There are two hypotheses as to its histogenesis: firstly, as a reaction to vegetable matter, such as legumes (thus the nomenclature "pulse" or edible seed) and secondly as a degenerative change in the vessel walls as a result of localized vasculitis. Due to the deceptive appearance of OPG, diagnosis can be challenging.

Cellular senescence in oral cancer and precancer and treatment implications: a review.

INTRODUCTION: Recent studies have demonstrated the capacity of the human organism to prevent the growth of potentially carcinogenic cells by paralyzing them. This antitumor mechanism is known as cellular senescence and is defined as an emergency defence system for cells on the way to becoming cancerous. RESULTS: This review of the literature suggests that oncogene-induced senescence may be a response to oncogenic activation, acting as a natural barrier against tumorigenesis at a premalignant stage. Thus, a large number of cells enter senescence in premalignant lesions but none do so in malignant tumors, due to the loss of senescent pathway effectors such as p16(INK4a) or ARF-p53. Potential senescence markers in oral precancerous lesions include p21(WAF1), p16(INK4a), pRb, Maspin, RAR-beta, G-actin, p15(INK4b), DCR2, and DEC1, some of which are currently under study. CONCLUSION: In the short term, the study of this mechanism may yield valuable data for the management of oral cancer and precancer, for which no effective diagnostic or prognostic markers are yet available.

Genotypic determination by PCR-RFLP of human papillomavirus in normal oral mucosa, oral leukoplakia and oral squamous cell carcinoma samples in Madrid (Spain).

BACKGROUND: Human papillomaviruses (HPVs), especially genotypes 16 and 18, are considered to be human carcinogens by the International Agency for Research on Cancer (IARC). They are the most important etiological agents of uterine cervix cancer but their true role in oral carcinogenesis is controversial. OBJECTIVES: To detect the presence of HPV genome genotypes in oral leukoplakia and oral squamous cell carcinoma (OSCC) and analyze their relationship with clinicopathological variables. MATERIALS AND METHODS: Presence of genome ofHPV types 6, 11, 16, 18, 31, 33, 39, 42, 45, and 52 was studied by polymerase chain reaction in samples of normal mucosa (30 controls), oral leukoplakia (35 cases) and OSCC (33 cases). Results were compared between groups and differences were examined in relation to clinical and histological variables. RESULTS: HPV genome was detected in 23.3% of controls, 45.7% of oral leukoplakias, and 39.4% of OSCCs. Only HPV-16 was significantly (p=0.0005) more frequently detected in leukoplakias (40%) and OSCCs (33.3%) versus controls (0%). No significant relationship was found between the presence of viral genome and the main clinicopathological variables. CONCLUSION: According to these findings, the presence of HPV-16 is significantly associated with oral leukoplakia and OSCC lesions, therefore in our setting this virus may be a carcinogenic element in this disease.

Relationship between oral Kaposi 's sarcoma and HAART: contribution of two case reports.

Two HIV infected patients not receiving Highly Active Antiretroviral Treatment (HAART) presented with epidemic Kaposi's sarcoma of the oral cavity. One patient initially refused HAART, but when the lesion became large enough to be noticeable he agreed to HAART associated with excision of the intraoral lesion by CO2 laser. The other patient developed KS and progressed to AIDS at two years after ceasing HAART due to adverse effects; he was referred to hospital for renewed administration of HAART. In both cases, the lesions observed in the oral cavity were the first clinical manifestation of AIDS. These reports underline the close relationship between the use of HAART and the control of KS lesions, highlighting the important role of the dentist in the identification and early diagnosis of these oral lesions.

Gene therapy in the management of oral cancer: review of the literature.

Gene therapy essentially consists of introducing specific genetic material into target cells without producing toxic effects on surrounding tissue. Advances over recent decades in the surgical, radiotherapeutic and chemotherapeutic treatment of oral cancer patients have not produced a significant improvement in patient survival. Increasing interest is being shown in developing novel therapies to reverse oral epithelial dysplastic lesions. This review provides an update on transfer techniques, therapeutic strategies, and the clinical applications and limitations of gene therapy in the management of oral cancer and precancer. We highlight the combination of gene therapy with chemotherapy (e.g., 5-Fluoracil) and immunotherapy, given the promising results obtained in the use of adenovirus to act at altered gene level (e.g., p53). Other techniques such as suicide gene therapy, use of oncolytic viruses or the use of antisense RNA have shown positive although very preliminary results. Therefore, further research into these promising gene therapy techniques is required to assess their true efficacy and safety in the management of these lesions.

Oral piercing: dental considerations and the legal situation in Spain.

Body piercing has become increasingly popular in Western countries, especially among young people. However, not everyone is aware of its potential risks, which may develop local and systemic complications shortly after, or long after the piercing procedure. Given that the oral cavity is one of the most frequent sites for piercing placement, the aim of this paper is to familiarise the oral healthcare professional with oral piercing and its possible sequelae in order to educate patients prior to and after piercing practices and address any complications that may arise.

Evaluation of minipigs as an animal model for alveolar distraction.

OBJECTIVE: Alveolar distraction osteogenesis is a relatively novel tissue regeneration technique that remains, in some respects, at an experimental stage. The selection of an experimental animal biomodel is not clearly defined, with reports in the reviewed literature on dogs, sheep, and monkeys. The present objective was to compare 2 experimental biomodels (dog and minipig) using an alveolar distraction protocol with a novel prototype distractor. STUDY DESIGN: Three beagle dogs and 3 Göttingen minipigs were evaluated, placing the distractor at the right hemimandible alveolar ridge after previous extraction of premolars. The radiological examination was carried out immediately after the distraction and at 2 weeks of consolidation. RESULTS: Satisfactory clinical and radiological results were obtained in 2 of 3 beagle dogs after the previous unilateral extraction of mandibular and maxillary premolars. During the consolidation, a height gain of approximately 5 mm was observed, with the appearance of radiodense bone trabeculae in the distraction chamber. The distraction failed in all of the minipigs. CONCLUSION: The minipig was not an appropriate biomodel for the study of alveolar distraction because the investigators were not able to maintain the seal of the distraction chamber or the stability of the distractor.

Undecalcified bone samples: a description of the technique and its utility based on the literature.

The evaluation of bone regeneration and peri-implantary bone apposition requires laboratory techniques that allow the evaluation of hard tissues without needing to decalcify them. In this study, we describe the cutting-grinding procedure (EXAKT system) for obtaining samples of undecalcified bone and aim to establish the procedures for their histological and histomorphometric evaluation. A review is made of the literature on histological and histomorphometric evaluation using undecalcified samples in surgical and oral implantology procedures in which bone regeneration or bone apposition is produced on the dental implants. The technique is a lengthy process, and is principally indicated in the investigation of bone biology. The use of undecalcified samples allows the differentiation of immature from mature bone, and the quantification of variables such as the bone-implant interface, the density of the bone area and the speed of bone apposition.

Dental management of patients with human immunodeficiency virus.

The demand for dental treatment by human immunodeficiency virus (HIV)-infected individuals is rising. Some professionals are still reluctant to treat these patients, despite the extremely low likelihood of professional transmission, which increases only in patients with a very elevated viral load. The complications rate after dental intervention is very low, even in patients with considerable immunologic deterioration. The dentist should pay special attention to the general clinical situation and immunologic and HIV virologic status of the seropositive patient, and to the presence of hemostasis alterations or of other concomitant diseases. Antiretroviral or any other drug treatments must also be recorded, in order to avoid possible interactions with clinician-prescribed drugs. Tooth extraction is the most common dental treatment and requires no antibiotic therapy except in cases of neutropenia or severe immunosuppression. Other dental treatments do not require special precautions, and the complications index among these patients is similar to that among the uninfected patient population. With this background, there is a need to make the clinician-in-training aware of the importance of regular dental health checkups as part of the health care routine of HIV-infected patients and to familiarize the clinician with their management, while not disregarding the unquestionable requirement to carry out the general and specific prevention measures to be adopted in all cases.

Differences in the expression of five senescence markers in oral cancer, oral leukoplakia and control samples in humans.

Oncogene-induced senescence (OIS) may be a response to oncogenic activation, acting as a natural barrier against carcinogenesis at a premalignant stage. Thus, numerous cells in premalignant lesions enter senescence, but none or few in malignant tumours. This event could be due to the loss of senescence pathway effectors, including p16 (INK4a)-pRb or ARF-p53. The aim of this study was to characterize and compare the expression of certain senescent markers between oral precancer and cancer tissue samples. The expression of cyclin D1, Rb, maspin, p53 and mouse double minute 2 (MDM2) was analyzed in 20 paraffin-embedded tissue samples of normal oral mucosa (NOM), 14 samples of oral leukoplakia without dysplasia (OLD-), 11 samples of leukoplakia with dysplasia (OLD+) and 15 samples of oral squamous cell carcinoma (OSCC) by immunohistochemistry in tissue arrays. The expression of p16-pRb pathway markers, cyclin D1, maspin and Rb, was more frequent in OLD+ samples than in OSCC samples, although a statistical significance was only observed for maspin (P=0.036). Cyclin D1 expression was also significantly more frequent in OLD- samples vs. NOM samples. For the ARF-p53 pathway, the expression of p53 and MDM2 was significantly more frequent in the OLD- samples compared to in the NOM ones. These findings may indicate a role for cellular senescence in oral carcinogenesis, considering maspin as a reliable senescence marker and prognostic factor in oral premalignant lesions.

Implications of prion diseases for dentistry: an update.

Prions are normal proteins present in all mammals, especially in the central nervous system (CNS) and lymphoreticular tissue. Their transformation into a highly infectious molecule gives rise to a group of diseases known as transmissible spongiform encephalopathies (TSEs), which cause vacuolar degeneration of gray matter and produce a fatal neurodegenerative disorder. Prion diseases have attracted considerable attention in recent years, and this review of the literature was designed to determine their implications for dentistry, studying the possibility of cross-transmission in the dental office and describing their oral manifestations. The main oral manifestations are dysphagia, dysarthria, paresthesias, dysesthesias, and dysgeusia. The most frequently involved oral tissues are the trigeminal ganglion, posterior third of the tongue, tonsils, and, much less commonly, alveolar nerves, gingiva, and salivary glands. Although no contagion has been reported in the dental setting to date, prions resist the usual dental sterilization systems and transmission of this type of disease remains a potential risk. It is therefore important for dentists to be aware of these diseases, to identify high-risk patients by obtaining an adequate clinical history, and to know the appropriate procedures to be followed.

In vitro study of the adherence of Candida albicans to acrylic resins: relationship to surface energy.

PURPOSE: This study aimed to determine whether small variations in the composition of the polymethylmethacrylate (PMMA) of widely used dentures produce differences in the degree of Candida albicans adherence and to relate any differences found to the surface energy of the resins, which appears to play a major role in the initial phases of microorganism adhesion. MATERIALS AND METHODS: A reference strain of C albicans (18.804 ATCC) and 11 different PMMAs (Vacalon, Inkotherm 85, Veracril, Probase Cold, Inkotherm Press, Inkotherm 85 T, Ruthinium, Vertex, SR Ivocap, Idoacryl, Lucitone) were used. Fifty specimens (15 x 10 x 1 mm) of each type were prepared. C albicans adhesion was determined by microorganism count under fluorescent optical microscope, and the surface energy of the resins was calculated by the contact angle method. P < .05 was regarded as significant. RESULTS: C albicans adhesion on the resins ranged from 7.12 cells/mm2 to 330.8 cells/mm2, with statistically significant (P > .05) differences in some cases. Despite small variations in the composition of the resins, their surface energy values were very similar (38.78 to 41.2 mJ/m2), and no relationship was found between C albicans adhesion and surface energy. CONCLUSION: The adhesion of C albicans to different resins varied in vitro, possibly as a result of the action of residual postpolymerization products. According to these results, variations in surface energy that result from differences in the composition of the different PMMA resins appear to have no influence on the adhesion of C albicans or, therefore, on the onset of denture stomatitis.

Características biológicas y clínicas de la mucosa periimplantaria / Biological and clinical aspects of perimplant mucosa

En este artículo revisamos las diferentes características morfológicas e histológicas de los tejidos periimplantarios. También analizamos las características bioquímicas, histométricas y la relación de las características del implante y el efecto de la carga oclusal sobre la osteointegración y la morfología de los tejidos periimplantarios