Evaluation of the Genotoxicity of Tobacco and Alcohol in Oral Mucosa Cells: A Pilot Study.

AIM AND OBJECTIVE: To define the genotoxic potential of tobacco and alcohol in the oral mucosa through a micronuclei (MN) test. MATERIALS AND METHODS: Samples of exfoliative cells from oral mucosa were collected using superficial scraping of the right- and left-cheek mucosa of 83 patients divided into four groups, namely: (G1) 24 individuals abstaining from tobacco and alcoholic beverages; (G2) 23 individuals who smoke and abstain from alcoholic beverages; (G3) 24 smokers and alcoholics; and (G4) 12 individuals who consume alcohol and abstain from tobacco. The samples were stained with Giemsa-Wright, and the frequencies of MN, binucleated cells, and metanuclear changes were recorded in the samples of each group (1,000 cells per patient). RESULTS: Analysis of variance (ANOVA) showed a difference between groups for changes concerning karyorrhexis (p = 0), pycnosis (p = 0.002), karyolysis (p = 0.003), and binucleated cells (p = 0.046). As for the total number of changes, G3, G2, and G4, respectively, were significantly higher than G1. CONCLUSION: It is suggested that the influence of smoking and drinking on exfoliating cells of oral mucosa may cause metanuclear changes due to genetic changes that these products cause, and the MN test is effective in detecting and monitoring such changes. CLINICAL SIGNIFICANCE: MN test may work for constantly monitoring the oral mucosa of smokers and/or alcoholic patients, so that early cell changes may be diagnosed, preventing the genesis of oral cancer.

Evaluation of a Series of Overdentures Made in a Higher Education Dental Institution in Southern Brazil.

AIM AND OBJECTIVE: This study aimed to evaluate the epidemiological profile, oral health self-perception index, and level of satisfaction of users of complete implant-supported overdentures that had been used for at least 1 year and were made at the School of Dentistry of the University of Passo Fundo, Rio Grande do Sul, Brazil (FO/UPF), between 2014 and 2019. MATERIALS AND METHODS: The sample consisted of 30 patients with overdentures, who were selected from the dental records filed at the institution. Data on general health and the dental implants involved (brand, type of prosthetic connection, number of implants, and additional overdenture retention system) were collected from the medical records. The 30 patients were invited to answer the Oral Health Impact Profile-14 (OHIP-14) and visual analog scale (VAS) questionnaires, and due to the coronavirus disease 2019 pandemic, it was possible to contact 15 patients. RESULTS: Most of the prostheses studied were mandibular overdentures, and 66.66% of the cases were retained by the O-ring system. As for the oral health self-perception of the individuals, it was concluded that male patients had a lower mean overall score (p = 0.047) and functional domain (p = 0.042) in the OHIP-14. The number of implants and the installation arch interfered with functional domain and psychological capacity (p <0.05). The VAS showed that women have greater esthetic satisfaction with prostheses (p = 0.048) and that the bar-clip retention system is more satisfactory than the O-ring (p = 0.017). CONCLUSION: Despite the limitations of overdentures, it was noted that, when properly indicated, they are a viable option for oral rehabilitation on implants. CLINICAL SIGNIFICANCE: Oral rehabilitation well-indicated with overdentures, especially those retained by the bar-clip system, results in an improvement in the patients' quality of life.

Oral Lesions found in a Dental School in Southern Brazil.

OBJECTIVE: This study aimed to perform an epidemiological survey of the cases of oral lesions diagnosed in a Brazilian dental school. MATERIALS AND METHODS: An epidemiological survey was carried out at the Faculty of Dentistry of the University of Passo Fundo (FOUPF), Rio Grande do Sul, Brazil, between March 2015 and June 2017, characterizing the patients in terms of gender, age, and ethnicity. A total of 3,200 records were evaluated, from which 716 presented information on oral lesions diagnosed and treated at the clinics of the FOUPF. The data were evaluated by descriptive statistics of frequency. RESULTS: The most frequent change was the coated tongue (13.83%). The majority of the patients were female (56%), white (31.57%), in the sixth decade of life (21.65%). Regarding the classification of lesions, the most frequent group was developmental changes (25%). CONCLUSION: It is considered that the sample studied presented a significant index of oral lesions and normality changes, considering that 716 (22.38%) patients studied showed some type of change in the oral cavity. CLINICAL SIGNIFICANCE: The sample studied presents peculiar characteristics regarding the number of oral lesions/conditions diagnosed. It is also considered that Schools of Dentistry are valuable environments for carrying out epidemiological surveys in stomatology, providing the diagnostic exercise, as long as the students are stimulated for this purpose.

A Comparison of Torque Stress on Abutment Screw of External Hexagon and Morse Taper Implant.

AIM: This three-dimensional (3D) finite element analysis observed the stress distribution on the prosthetic screws on external hexagon implant and morse taper implant with different tightening loads. MATERIALS AND METHODS: For this, two different 3D models assembly were obtained from the manufacturer and transferred to finite element analysis software: External hex implant model (EHM), and Morse taper implant model (MTM), both compounds by 3.75 × 7 mm implant, abutment and abutment screw. Bolt pretension force was applied on the shaft next to the threads of the prosthetic abutment. Preload was calculated using the torque on the prosthetic screw as recommended by the manufacturer (EHM30 and MTM20) and 10 Ncm torque above the manufacturer recommendations (EHM40 and MTM30). Maximum von mises equivalent stresses were obtained on the screws. RESULTS: Preload values results were 243.18N (EHM30), 229.71N (MTM20), 324.24N (EHM40) and 344.57N (MTM30). In EHM30, EHM40 and MTM20 models the maximum stresses were below the yield strength of the abutment screw material. However, the maximum stress in MTM30 model was higher than the reference value. CONCLUSION: The torque loads above the manufacturer recommendations can cause plastic deformation in the MT abutment screw threads. The screws of morse taper implant can be more sensitive to higher loads than external hexagon implant. CLINICAL SIGNIFICANCE: The adequate torque can result in screw loosening, while fracture may occur if torque is excessive. Abutment screw suffers many screwing cycles in its lifetime in a way that some tightening forces are above manufacturer recommendations.

Evaluation of Cellular Proliferative Activity in Patients with Actinic Cheilitis through Silver-stained Nucleolar Organizer Region Method.

Introduction: Actinic cheilitis (AC) is a lesion potentially malignant that affects the lips after prolonged exposure to solar ultraviolet (UV) radiation. The present study aimed to assess and describe the proliferative cell activity, using silver-stained nucleolar organizer region (AgNOR) quantification proteins, and to investigate the potential associations between AgNORs and the clinical aspects of AC lesions. Materials and methods: Cases diagnosed with AC were selected and reviewed from Center of Histopathological Diagnosis of the Institute of Biological Sciences, Passo Fundo University, Brazil. Clinical data including clinical presentation of the patients affected with AC were collected. The AgNOR techniques were performed in all recovered cases. The different microscopic areas of interest were printed with magnification of *1000, and in each case, 200 epithelial cell nuclei were randomly selected. The mean quantity in each nucleus for NORs was recorded. One-way analysis of variance was used for statistical analysis. Results: A total of 22 cases of AC were diagnosed. The patients were aged between 46 and 75 years (mean age: 55 years). Most of the patients affected were males presenting asymptomatic white plaque lesions in the lower lip. The mean value quantified for AgNORs was 2.4 ± 0.63, ranging between 1.49 and 3.82. No statistically significant difference was observed associating the quantity of AgNORs with the clinical aspects collected from the patients (p > 0.05). Conclusion: The present study reports the lack of association between the proliferative cell activity and the clinical aspects observed in patients affected by AC through the quantification of AgNORs. Clinical significance: Knowing the potential relation between the clinical aspects of AC and the proliferative cell activity quantified by AgNORs could play a significant role toward the early diagnosis of malignant lesions in the clinical practice. Keywords: Actinic cheilitis, Proliferative cell activity, Silver-stained nucleolar organizer regions.

Influence of Age on Factors associated with Peri-implant Bone Loss after Prosthetic Rehabilitation over Osseointegrated Implants.

INTRODUCTION: To verify the influence of age on factors associated with peri-implant bone loss after prosthetic rehabilitation over osseointegrated implants. MATERIALS AND METHODS: This is an analytical, observational, and longitudinal study with initial 23 participants. Patients presenting with osseointegrated implants with their respective prostheses installed were included, and they could be carriers of chronic and degenerative diseases, such as diabetes, osteoporosis, hypothyroidism, cardiovascular disease (CVD), and systemic arterial hypertension. Thus, 18 participants with 57 implants were selected and followed up from 2009 to 2013. For statistical analysis, chi-square or Fisher's exact test was used for the association of systemic conditions and bone loss. Student's t-test was used for mean comparisons of age and number of total upper and lower implants. RESULTS: The average age of the sample studied was 71.05 years (65-80). The average implant per person was 3.2. Smoking had an influence on both mesial and distal bone loss, and the latter was significant (p = 0.0370). The association between bone loss and gender was also significant (p < 0.05). Moreover, male gender and upper implants were factors significantly associated with bone loss. The systemic conditions, when isolated, did not have significant influence on implant survival. CONCLUSION: Age is not a factor that, alone, contraindicates implant-rehabilitating therapy. On the contrary, smoking has a significant influence on dental implant survival. Systemic diseases, such as osteoporosis, hypothyroidism, diabetes, hypertension, and heart diseases, when controlled, are not contraindication factors. CLINICAL SIGNIFICANCE: This study is relevant for assessing peri-implant bone loss in elderly patients, right after implant installation and over time. Therefore, it was possible to verify that age is not a limiting factor for this procedure. Controlled systemic diseases do not contraindicate implant installation, but smoking is a factor that affects implant survival.

Prevalence of self-reported halitosis and associated factors in adolescents from Southern Brazil.

The aim of this study was to assess the prevalence of selfreported halitosis and associated factors in adolescents from Passo Fundo, Brazil. Additionally, we studied adolescents' concern with their own breath and whether anyone had ever told them that they had halitosis. A crosssectional observational survey was conducted on 15to 19year old high school students from public and private schools in the city of Passo Fundo, Brazil. The random sample consisted of 736 adolescents from 20 schools. An interview with a structured questionnaire was administered. The prevalence of selfreported halitosis and associated factors was analyzed by either the chisquare test or Fisher's exact test. The prevalence of selfreported halitosis was 39.67%. The mother's level of education was associated with the outcome. Gender and behavioral habits were not associated with selfreported halitosis. Halitosis reported by others presented a prevalence of 10.73% and was associated to male gender and oral hygiene habits. Individuals with less toothbrushing frequency and no use of dental floss were associated to halitosis reported by others. It was observed that 88.58% of the participants are concerned with halitosis. It is concluded that there is high prevalence of selfreported halitosis, which is associated with a socioeconomic pattern. Most adolescents report concern with their own breath.

O objetivo do presente estudo foi verificar a prevalência de halitose autorreportada e fatores associados em adolescentes de Passo Fundo, Brasil. Além disso, foram verificados a preocupação dos adolescentes com o seu próprio hálito e se eles já foram avisados por alguém sobre essa condição em qualquer momento de suas vidas. Esse estudo transversal envolveu estudantes do ensino médio, da rede pública e privada, com idades entre 15 e 19 anos, da cidade de Passo Fundo, Brasil. Uma amostra randômica de 736 adolescentes de 20 escolas foi utilizada. Um questionário estruturado foi aplicado. A prevalência de halitose autorreportada e fatores associados foram analisados por quiquadrado ou teste exato de Fischer. A prevalência de halitose autorreportada foi de 39,67%. O nível educacional da mãe foi associado com esse desfecho. Gênero e hábitos comportamentais não estiveram associados com halitose autorreportada. Apenas 10,37% dos adolescentes reportadam que outras pessoas indicaram a existência desse problema, sendo associada com o gênero masculino e com hábitos de higiene bucal. Os indivíduos que reportaram menor frequência de escovação dentária e ausência do uso de fio dental apresentaram associações com a advertência da halitose por outras pessoas. Foi observado que 88,58% dos participantes são preocupados com o próprio hálito. Concluiuse que a halitose autorreportada apresenta alta prevalência e está associada com fatores socioeconômicos. Advertência sobre mau hálito por outras pessoas foi relatada apenas por uma minoria, sendo associado com o gênero masculino e hábitos de higiene bucal. A maioria dos adolescentes reportou preocuparse com o próprio hálito.