Growth dynamics of nanocolumnar thin films deposited by magnetron sputtering at oblique angles.

The morphology of numerous nanocolumnar thin films deposited by the magnetron sputtering technique at oblique geometries and at relatively low temperatures has been analyzed for materials as different as Au, Pt, Ti, Cr, TiO2, Al, HfN, Mo, V, WO3and W. Despite similar deposition conditions, two characteristic nanostructures have been identified depending on the material: a first one defined by highly tilted and symmetric nanocolumnar structures with a relatively high film density, and a second one characterized by rather vertical and asymmetric nanocolumns, with a much lower film density. With the help of a model, the two characteristic nanostructures have been linked to different growth dynamics and, specifically, to different surface relaxation mechanisms upon the incorporation of gaseous species with kinetic energies above the surface binding energy. Moreover, in the case of Ti, a smooth structural transition between the two types of growths has been found when varying the value of the power used to maintain the plasma discharge. Based on these results, the existence of different surface relaxation mechanisms is proposed, which quantitatively explains numerous experimental results under the same conceptual framework.

Multigene phylogeny of the order Physarales (Myxomycetes, Amoebozoa): shedding light on the dark-spored clade.

The class Myxomycetes consists of free-living protists characterised by their complex life cycle, which includes both microscopic (amoebae, flagellates and cists) and macroscopic stages (spore-bearing fruiting bodies, sclerotia, and plasmodia). Within it, the order Physarales, with more than 450 recognised species, constitutes the largest group. Although previous studies have shown the polyphyly of some of the traditionally accepted genera, its internal phylogenetic relationships have remained uncertain so far, and together with the lack of data for some key species, it prevented any taxonomic and nomenclatural revisions. We have compiled a substantially expanded dataset in terms of both taxon sampling and molecular data, including most of the genera described to date and four unlinked DNA regions, for which we provide partial sequences: nSSU, EF-1α, α-Tub, and mtSSU, analysed through maximum likelihood and Bayesian methods. Our results confirm that the family Didymiaceae is paraphyletic to the rest of Physarales. Within Didymiaceae s.lat., the recent reinstatement of the genus Polyschismium for most species traditionally ascribed to Lepidoderma, except for the type (Ronikier et al. 2022), is further supported here, as well as the definite inclusion of the genus Mucilago in Didymium and Lepidoderma s.str. (L. tigrinum) in Diderma (Prikhodko et al. 2023). Additionally, the genus Diachea is redefined to include some species previously treated in Physaraceae (Craterium spp. with true columella). Within the monophyletic family Physaraceae, most genera are recovered as polyphyletic, suggesting that they should be no longer accepted as currently defined. However, the lack of resolution of some relationships within Physaraceae prevents us from resuscitating or creating several new genera to mitigate polyphyly. Among the well-defined groups with clear molecular signatures, we propose two taxonomic and nomenclatural changes at generic level: 1) a new genus, Nannengaella, is proposed for a major clade containing Physarum globuliferum and other species with heavily calcified sporophores and, often, a true calcareous columella; 2) Lignydium is resurrected for the clade containing Fuligo muscorum. Additionally, Trichamphora is suggested as the correct name for the clade containing Physarum pezizoideum. The taxonomy and nomenclature of some provisional genera, currently synonymous with Fuligo and Physarum, are disentangled, and we provide a comprehensive and updated nomenclatural conspectus that can be used when better resolved phylogenies are obtained. In total, 22 new combinations are proposed in different genera. A provisional key to the genera of the order is also provided. Citation: García-Martín JM, Zamora JC, Lado C. 2023. Multigene phylogeny of the order Physarales (Myxomycetes, Amoebozoa): shedding light on the dark-spored clade. Persoonia 51: 89-124. doi: 10.3767/persoonia.2023.51.02.

Assessment of direct analysis in real time accurate mass spectrometry for the determination of triclosan in complex matrices.

In this work, the applicability of direct analysis in real time coupled to accurate mass spectrometry (DART-MS) to the quantitative determination of triclosan (TCS) in samples with increasing complexity, from personal care products to extracts from sewage, is investigated. In the first term, DART-MS spectra of TCS as free phenol and as derivatized species are characterized; thereafter, the effects of several instrumental variables in the detectability of TCS (i.e., temperature, solvent, and compound holder) are discussed. Under final selected conditions, TCS was determined from its [M-H]- ions, without need of derivatization, attaining an instrumental limit of quantification of 5 ng mL-1, with a linear response range up to 1000 ng mL-1. Complex matrices, such as solid-phase extracts obtained from environmental water samples, moderately inhibited the ionization efficiency of TCS, with signal attenuation percentages in the range of 6 to 57%, depending on the sample type and on the concentration factor provided by the SPE procedure. The accuracy of results obtained by DART-MS was evaluated using liquid chromatography (LC) with MS detection; in both cases, a time-of-flight (TOF) MS instrument was employed for the selective determination of the [M-H]- ions of TCS (m/z values 286.9439 and 288.9410) using a mass window of 20 ppm. DART-MS did not only provide enough sensitivity to detect the presence of TCS in environmental samples (raw and treated wastewater as well as freeze-dried sludge), but also measured concentrations matched those determined by LC-ESI-TOF-MS, with only slightly higher standard deviations. During analysis of personal care products, containing much higher concentrations of TCS in a less complex matrix, both techniques were equivalent in terms of accuracy and precision. Graphical abstract.

Promoting oral health among 6-year old children: The impact of social environment and feeding behavior.

OBJECTIVE: To determine the prevalence of dental caries and identify key associated factors, including eating habits, body mass index, and the presence of dental plaque in immigrant and indigenous children. BASIC RESEARCH DESIGN: Observational study with immigrant and native child populations (aged 6 years) with logistic regression analysis. SETTING: Oral Public Health Service in the Asturias region of Spain. PARTICIPANTS: The presence of dental caries (World Health Organization) and oral hygiene (O'Leary index) were determined in 166 children. Information on eating habits was collected through a survey on food consumption (European Food Safety Authority). RESULT: Children from immigrant families had more decayed and filled teeth index (2.59 vs. 0.21; Crude OR: 7.99 [95% CI 3.620-17.636]). In univariate analysis, protective factors were daily intake of milk and fruits (p ⟨0.001). In multivariate analysis, the presence of caries was associated with immigrant status, consumption of sugary foods, and being overweight, (OR: 13.179 [4.668-37.208]). CONCLUSION: Public Institutions must take into account our results to help reduce caries in immigrant children.

Evidence of Intra-individual SSU Polymorphisms in Dark-spored Myxomycetes (Amoebozoa).

The nuclear small subunit rRNA gene (SSU or 18S) is a marker frequently used in phylogenetic and barcoding studies in Amoebozoa, including Myxomycetes. Despite its common usage and the confirmed existence of divergent copies of ribosomal genes in other protists, the potential presence of intra-individual SSU variability in Myxomycetes has never been studied before. Here we investigated the pattern of nucleotide polymorphism in the 5' end fragment of SSU by cloning and sequencing a total of 238 variants from eight specimens, each representing a species of the dark-spored orders Stemonitidales and Physarales. After excluding singletons, a relatively low SSU intra-individual variability was found but our data indicate that this might be a widely distributed phenomenon in Myxomycetes as all samples analyzed possessed various ribotypes. To determine if the occurrence of multiple SSU variants within a single specimen has a negative effect on the circumscription of species boundaries, we conducted phylogenetic analyses that revealed that clone variation may be detrimental for inferring phylogenetic relationships among some of the specimens analyzed. Despite that intra-individual variability should be assessed in additional taxa, our results indicate that special care should be taken for species identification when working with closely related species.

Kinetic energy-induced growth regimes of nanocolumnar Ti thin films deposited by evaporation and magnetron sputtering.

We experimentally analyze different growth regimes of Ti thin films associated to the existence of kinetic energy-induced relaxation mechanisms in the material's network when operating at oblique geometries. For this purpose, we have deposited different films by evaporation and magnetron sputtering under similar geometrical arrangements and at low temperatures. With the help of a well-established growth model we have found three different growth regimes: (i) low energy deposition, exemplified by the evaporation technique, carried out by species with typical energies in the thermal range, where the morphology and density of the film can be explained by solely considering surface shadowing processes, (ii) magnetron sputtering under weak plasma conditions, where the film growth is mediated by surface shadowing mechanisms and kinetic-energy-induced relaxation processes, and (iii) magnetron sputtering under intense plasma conditions, where the film growth is highly influenced by the plasma, and whose morphology is defined by nanocolumns with similar tilt than evaporated films, but with much higher density. The existence of these three regimes explains the variety of morphologies of nanocolumnar Ti thin films grown at oblique angles under similar conditions in the literature.

Oral hygiene instructions and professional control as part of the treatment of desquamative gingivitis. Systematic review.

BACKGROUND: The aim of this present article was to evaluate the scientific evidence on the efficacy of daily hygiene and professional prophylaxis for treatment of desquamative gingivitis. MATERIAL AND METHODS: The present systematic review was conducted following the PRISMA protocol. Searches were carried out in Pubmed, Embase, Web of Science and Cochrane Library up to July 2018, randomized clinical trials and cohort studies on desquamative gingivitis (DG), and oral diseases joined to DG. RESULTS: After screening, we found that nine publications met the eligibility criteria eight cohort studies and one randomized control trial. The diagnosis of the diseases corresponded to oral lichen planus (n=185), mucous membrane pemphigoid (n=13); plasma cell gingivitits (n=15) and pemphigus vulgar (n=11). The follow-up was between a week and a year after instructing patients. Dental daily hygiene and professional prophylaxis, at least with supragingival scaling and polishing have significantly improved the extension of the lesion and reduced the activity of DG, and gingival bleeding in all patients. Furthermore, these techniques have also reduced pain and gingival plaque. CONCLUSIONS: In conclusion the studies presented support the efficacy of maintaining personal and professional oral hygiene in patients with GD, reducing the clinical signs of the disease, regardless of its pathogenesis.

Tuning the size, composition and structure of Au and Co50Au50 nanoparticles by high-power impulse magnetron sputtering in gas-phase synthesis.

Gas-phase synthesis of nanoparticles with different structural and chemical distribution is reported using a circular magnetron sputtering in an ion cluster source by applying high-power impulses. The influence of the pulse characteristics on the final deposit was evaluated on Au nanoparticles. The results have been compared with the more common direct current approach. In addition, it is shown for the first time that high-power impulses in magnetron based gas aggregation sources allows the growth of binary nanoparticles, CoAu in this case, with a variety of crystalline and chemical arrangements which are analyzed at the atomic level.

Geographic tongue: Predisposing factors, diagnosis and treatment. A systematic review. / Lengua geográfica: factores predisponentes, diagnóstico y tratamiento. Revisión sistemática.

INTRODUCTION: Geographic tongue (GT) is a lesion of unknown origin associated with systemic diseases and therefore involves multidisciplinary care. METHODS: We performed a literature search of the PubMed, EMBASE, Web of Science and Cochrane databases. The selection criteria were consistent with the Preferred Reporting Items for Systematic Reviews protocol. We considered as inclusion criteria journal articles designed on cases of cohorts, cross-sectional studies, cases and controls and randomised clinical trials in the pathogenic, clinical and therapeutic context. RESULTS: A total of 33 articles met these criteria. We analysed 4998 patients with GT, with an age range of 0 to 85 years, and the burning sensation symptom was present in 9.2-47% of these patients. The GT diagnosis was clinical in 98.81% of the cases, and GT displayed an association with psoriasis, allergies and anxiety. Candida infection was present in 7.6% (24/315) of the cases, and the presence of caries was statistically significant. The only analysed clinical trial proposed treatment through the topical application of 0.1% triamcinolone acetonide combined or not with 0.05% retinoic acid. CONCLUSIONS: The diagnosis of GT is mainly clinical. GT is an asymptomatic disorder that usually requires no treatment. Understanding GT is necessary due to the comorbid intraoral and extraoral diseases that accompany the condition.

Investigation of split CoFeB/Ta/CoFeB/MgO stacks for magnetic memories applications.

We report on the static and dynamic magnetic properties of W/CoFeB/Ta/CoFeB/MgO stacks, where the CoFeB layer is split in two by a 0.3 nm-thick Ta "dusting" layer. A total CoFeB thickness between 1.2 and 2.4 nm is studied. Perpendicular magnetic anisotropy is obtained for thickness below 1.8 nm even at the as-deposited stacks, and it is enhanced after annealing. Saturation magnetization is 1520 (1440) kA/m before (after) annealing, increased compared to non-split CoFeB layers. Ferromagnetic resonance measurements show that high magnetic anisotropy energy may be achieved (effective anisotropy field 0.571 ± 0.003 T), combined to a moderate Gilbert damping (0.030 ± 0.001). We argue that the above characteristics make the split-CoFeB system advantageous for spintronics applications.

The length of patient and primary care time interval in the pathways to treatment in symptomatic oral cancer. A quantitative systematic review.

OBJECTIVES: To examine the relative length of the patient and primary care intervals in symptomatic oral cancer. DESIGN: Quantitative systematic review. SEARCH STRATEGY: Oral cancer OR oral squamous cell carcinoma OR oropharyngeal cancer AND time interval OR diagnostic delay. SETTING: Primary and secondary care. PARTICIPANTS: Oral and oropharyngeal cancer patients. MAIN OUTCOME MEASURES: We computed five measures (patient, primary care, diagnosis, total diagnosis and total treatment intervals). Most studies did not provide any dispersion measure. We then used the sample size of each study to compute a weighted average of the mean intervals. When the median was provided, we assumed normality of the distribution of the means and used the median as a proxy of the mean. RESULTS: A total of 1089 articles were identified, and 22 met the inclusion criteria, reporting on 2710 patients from Europe, USA, India, Australia, Japan, Argentina and Iran. The weighted average of patient interval was 80.3 days. Primary care interval was five times shorter: 15.8 days. The diagnostic interval was appreciably shorter (47.9 days) when compared with the patient interval during symptomatic period. CONCLUSIONS: Patient interval represents the major component of waiting times since the detection of the first signs/symptoms to the definitive diagnosis of oral cancer. Thus, strategies focused on high-risk patients should be prioritised. Interventions aimed at optimising the health systems should be implemented by monitoring and facilitating diagnostic and treatment pathways of patients with oral cancer.

Distance of the alveolar antral artery from the alveolar crest. Related factors and surgical considerations in sinus floor elevation.

BACKGROUND: In a variable proportion of maxillary sinuses alveolar antral artery is located close to the residual ridge, increasing the chances for haemorrhagic complications during sinus floor elevation procedures. MATERIAL AND METHODS: Retrospective observational study of CBCT explorations performed for implant-treatment planning. The upper first molar area was selected for this study. The relative uncertainty (standard deviation of the measurement divided by its mean and expressed as a percentage from 0% to 100%) was chosen for determining the observational errors. For modeling the chances of AAA detection, the generalized additive models (GAM) approach was chosen. RESULTS: A total of 240 maxillary sinuses were studied (46.25% males) whose median median age was 58 years old (IQR: 52-66). Univariate models showed that the chances for an AAA-alvelar crest distance ≤15mm increase in wider sinuses with lower, subsinusally edentulous crests. When distance is considered as a continuous variable, the best mutivariate model showed an explained deviance of 67% and included AAA diameter, distance AAA-sinus floor, sinus width, and shape, height and width of the residual ridge. Thinner AAAs are found closer to the crest (within the ≤15mm safe distance). CONCLUSIONS: Bearing in mind the inclusion criteria and the limitations of this investigation, it is concluded that there is a high proportion of maxillary sinuses where AAA describes a course close to the alveolar crest (≤15mm), which was classically considered a safe distance for SFE. This position is related to the presence of atrophic crests (depressed ridge form) and wide maxillary sinuses where the distance of the vessel to the floor of the sinus is small. This information may permit a better surgical planning of SFE procedures.

The development of proliferative verrucous leukoplakia in oral lichen planus. A preliminary study.

BACKGROUND: Was to describe 14 cases of a proliferative verrucous leukoplakia as a clinical evolution of oral lichen planus. MATERIAL AND METHODS: The clinical and histopathological characteristics of 14 cases of OLP that progress towards a plaque-like and verrucous form were indicated, with monitoring over a period of six to 24.3 years. RESULTS: The female/male ratio was 11/3, (78.6 and 21.4%). The mean age when the first biopsy was undertaken was 56.4 years old. None of the patients smoked during the study. As bilateral reticular was clinically diagnostic criterion, the second most frequent clinical form was the plaque form (n=10; 71.4%), followed by the atrophic (n=6; 42.8%), and erosive forms (n=4; 28.5%). Clinically it spread towards attached gingival mucosa and the hard palate. In the histopathologic study, there were a predominance of hyperkeratosis and verrucous epithelial hyperplasia. Three of the cases progressed to a squamous cell carcinoma, and one patient developed two verrucous carcinoma. CONCLUSIONS: Further research is needed to demonstrate if proliferative multifocal oral lichen planus and proliferative multifocal oral leukoplakia are the same disorder but have different behaviour of malignancy for reasons of origin.

Torsional resonance mode magnetic force microscopy: enabling higher lateral resolution magnetic imaging without topography-related effects.

We present experimental work that reveals the benefits of performing magnetic force microscopy measurements employing the torsional resonance mode of cantilever oscillation. This approach provides two clear advantages: the ability of performing magnetic imaging without topography-related interference and the significant lateral resolution improvement (approximately 15%). We believe that this work demonstrates a significant improvement to a versatile magnetic imaging technique widely used in academia and in industry.

Magnetic modulation of surface plasmon modes in magnetoplasmonic metal-insulator-metal cavities.

The magnetic modulation of the surface plasmon-polariton (SPP) wavevector is experimentally and theoretically studied for the plasmonic modes excited in metal-insulator-metal (MIM) magnetoplasmonic cavities. For this purpose, Ag/SiO2/Ag multilayers with different SiO2 layer thickness in which a thin Co layer is positioned near the top Ag/SiO2 interface, near the bottom SiO2/Ag one, or near both of them, are studied. The magnetoplasmonic MIM cavities present symmetric (SM) and antisymmetric (AM) plasmonic modes, of different wavevector and electromagnetic field profiles inside the MIM cavity. We show that the magnetic SPP wavevector modulation strongly depends on which mode is considered, the cavity thickness, and the number and specific location of Co layers within the structure. With only one ferromagnetic layer, a net modulation is obtained, of higher magnitude as we reduce the SiO2 layer thickness. The introduction of a second Co layer in the structure reduces the modulation due to the non-reciprocal character of SPP modes under an applied magnetic field. Moreover, we demonstrate that the non-reciprocal nature of the SPP modulation can be experimentally visualized in the magnetic hysteresis loops under plasmon excitation conditions by using two Co layers with different magnetization switching fields.

Growth regimes of porous gold thin films deposited by magnetron sputtering at oblique incidence: from compact to columnar microstructures.

Growth regimes of gold thin films deposited by magnetron sputtering at oblique angles and low temperatures are studied from both theoretical and experimental points of view. Thin films were deposited in a broad range of experimental conditions by varying the substrate tilt angle and background pressure, and were analyzed by field emission scanning electron microscopy and grazing-incidence small-angle x-ray scattering techniques. Results indicate that the morphological features of the films strongly depend on the experimental conditions, but can be categorized within four generic microstructures, each of them defined by a different bulk geometrical pattern, pore percolation depth and connectivity. With the help of a growth model, a microstructure phase diagram has been constructed where the main features of the films are depicted as a function of experimentally controllable quantities, finding a good agreement with the experimental results in all the studied cases.

Ligand adsorption on an activated carbon for the removal of chromate ions from aqueous solutions.

The results presented in this work are related to the design of a guideline to develop specific properties at the surface of an activated carbon (AC). For this, two model aromatic compounds have been synthesized and their electrolytic behavior in aqueous solutions was studied by a potentiometric method. The textural characteristics of the activated carbon were determined by porosimetry methods. The nature of oxygen-carrying functions and the acid-base behavior of the AC surface were characterized by TPD and potentiometric titration methods, respectively. The adsorption and desorption equilibria of the aromatic compounds on activated carbon were measured in aqueous solutions, and the hysteresis between adsorption and desorption, which reveals irreversible adsorption, was discussed on the basis of the frontier orbital theory. HOMO and LUMO orbitals of the adsorbent and adsorbates were calculated, and irreversible adsorption was attributed to the small energy difference between HOMO and LUMO of the aromatic adsorbates and the adsorbent. Adsorption equilibria of K2CrO4 in aqueous solution on the AC alone and on the AC-aromatic ligand adsorbents, respectively, prove the efficient development of specific chemical functions at the carbon surface provided by the adsorbed aromatic compounds.

[Circadian variations in proinflammatory cytokine concentrations in acute myocardial infarction]. / Ritmo luz/oscuridad de las citocinas proinglamatorias en el infarto agudo de miocardio.

INTRODUCTION AND OBJECTIVES: The concentration of certain proinflammatory cytokines has been found to be elevated in patients with acute coronary syndrome. Many studies have shown that coronary ischemic accidents do not show a uniform distribution throughout the day, but instead exhibit rhythmic variations. The objective of this study is to determine whether there is a circadian pattern of variation in the concentrations of proinflammatory cytokines in patients with acute myocardial infarction. PATIENTS AND METHOD: The sample included 40 patients with acute myocardial infarction and 40 controls. Levels of interleukin 6 and 1 beta were determined in the first 24 hours after the acute coronary ischemic episode. Blood samples were extracted at 3:00 a.m. (period of darkness) and at 10:00 a.m. (period of daylight). RESULTS: Both groups were similar in age, sex distribution, and coronary risk factors. Interleukin 6 levels showed a significant variation between daylight and nighttime concentrations in patients with acute myocardial infarction and controls (41.93 5.90/100.39 13.60 vs 25.76 4.45/52.67 7.73 pg/ml). However, interleukin 6 concentrations were higher in the acute myocardial infarction group than in the control group. Interleukin 1 beta concentrations did not vary between daylight and darkness. CONCLUSIONS: In both the control group and acute myocardial infarction group, interleukin 6 concentrations varied between daylight and darkness. Patients with acute myocardial infarction shown a higher concentration of interleukin 6 secondary to the physiological response to tissue damage. Circadian variations can affect the measurements obtained for different physiological and biochemical parameters.

Decreased nocturnal melatonin levels during acute myocardial infarction.

Acute myocardial infarction is accompanied by an increase in cellular oxidative stress in the pericardial coverings of the heart. Melatonin is a highly potent and efficient radical scavenger. Little research has been carried out concerning the relationship between this antioxidant and acute myocardial infarction in humans. In this work, serum levels of melatonin and parameters of oxidative stress, such as glutathione peroxidase and lipid peroxidation levels were examined in light/dark periods in patients with acute myocardial infarction. Twenty-five patients diagnosed with acute myocardial infarction were studied and 25 patients with no evidence of coronary artery disease served as controls. Venous blood samples were obtained from the patients and control subjects to determine melatonin, glutathione peroxidase and lipid peroxidation; the samples were collected at 10:00 hr (light period) and 03:00 hr (dark period) in the first 24 hr after admission to the coronary care unit. Our results demonstrate the existence of differences between changes in melatonin levels in control subjects and acute myocardial infarction patients, revealing a reduced nocturnal elevation in the acute myocardial infarction group. Glutathione peroxidase levels were lower after acute myocardial infarction and did not show diurnal variations. In the control group, lipid peroxidation levels presented a light/dark pattern but in the acute myocardial infarction group diurnal variations of this parameter were lost. Our data show that acute myocardial infarction is associated with a nocturnal serum melatonin deficit as well as increased oxidative stress, suggesting that melatonin is, at least in part, depleted during the dark phase to reduce the free radicals formed in acute myocardial infarction.

Risk factors for oral soft tissue lesions in an adult Spanish population.

OBJECTIVES: The aims of this study were (i) to determine the prevalence of oral lesions in adults over 30 years old in the city of Oviedo (Spain), and (ii) to analyze the relationship between the prevalence of oral lesions, toxic habits (tobacco and alcohol) and denture wearers in these patients. METHODS: A representative sample of the adult population in Oviedo (Spain) was obtained through randomized sampling (n = 753); a total of 308 (41%) subjects were finally included in the study. The observed oral pathology was classified according to the WHO criteria and earlier epidemiological studies. RESULTS: A little over half of all patients (51.1%) had oral lesions. The most frequent lesions were frictional lesion (7.5%), traumatic ulcer (7.1%), denture stomatitis and pseudomembranous candidosis (6.5%), followed by melanin pigmentation (5.8%) and denture-induced hyperplasia (5.2%), plicated tongue (3.9%), lichen planus and hemangioma (3.2%), angular cheilitis and cheek biting (2.9%), fibrous hyperplasia and coated tongue (2.6%), recurrent aphthae (1.9%) and oral leukoplakia (1.6%). In relation to leukoplakia, the odds ratio (OR) of heavy drinkers was 15.98 and the OR of heavy smokers was 12.37. The OR of heavy smokers or heavy drinkers diagnosed of frictional lesion was four times greater than that of nonsmokers or nondrinkers. The OR of heavy smokers with melanic pigmentations was 4.08. The OR of complete denture wearers with candidosis was 11.38. The OR of partial removable denture wearers with hemangioma was 5.01. CONCLUSIONS: This study shows the relation of heavy tobacco and heavy alcohol to traumatic keratosis and leukoplakia, and of complete dentures to pseudomembranous candidosis, fibrous hyperplasia and stomatitis. Programs designed to eradicate toxic factors (alcohol and tobacco) should, therefore, be implemented with adequate maintenance of dentures.