Dental black plaque: metagenomic characterization and comparative analysis with white-plaque.

Extrinsic black dental staining is an external dental discoloration of bacterial origin, considered a special form of dental plaque. Currently, there is no definitive therapeutic option for eliminating black stain. This study employed 16S rRNA metagenomics to analyze black stain and white-plaque samples from 27 adult volunteers. Study objectives were to: describe the microbial diversity of adult black stain samples; characterize their taxonomic profile; compare the microbiomes of black stain versus white-plaque from adult volunteers and propose a functional map of the black stain microbiome using PICRUSt2. The black stain microbiome was poorer in species diversity as compared to white-plaque. The five most abundant genera in black stain were Capnocytophaga, Leptotrichia, Fusobacterium, Corynebacterium and Streptococcus. Functional analysis of microbial species revealed conserved and consistent clustering of functional pathways within and between black stain and white-plaque microbiomes. We describe enrichment of heme biosynthetic pathways in black stain. Our results suggest that the dysbiosis in black stain resembles "orally healthy" communities. The increased abundance of heme biosynthetic pathways suggests that heme-dependent iron sequestration and subsequent metabolism are key for black stain formation. Further research should decipher the regulation of heme biosynthetic genes and characterize the temporal sequence leading to colonization and dysbiosis.

Raising awareness about microbial antibiotic resistance in undergraduate dental students: a research-based strategy for teaching non-laboratory elements of a microbiology curriculum.

BACKGROUND: Resistance to antimicrobial agents has become a problem in modern society. Antibiotic resistant bacteria undermine the prevention and treatment of infections. Undergraduate dental students in Europe are required to receive information in aspects of microbiology relevant for dental practice, including oral microbial pathogens and resistance mechanisms against antimicrobial compounds. The objective of this study was to implement a research-based strategy to aid the understanding of the increase in antimicrobial resistance in undergraduate dental student training. The primary outcome of this project is the efficacious delivery of the learning objectives. METHODS: Ten volunteer undergraduate student "ambassadors" were recruited to manage the project with assistance from lead academics. Student ambassadors were a source of peer learning for their colleagues. The project consisted of three phases: Pre-project preparation (in which the ambassadors received special instruction and training); Practical experience (in which the ambassadors worked with volunteer student colleagues to carry out the project); Public presentation of results (in which ambassadors presented study results at a scientific conference of their choosing). RESULTS: A total of 1164 students volunteered for the project, corresponding to an average participation rate of 76.4% students per year of the course. Following final debriefing, student participants and ambassadors were strongly positive in their evaluation of the achievement of 8 key student learning objectives. The results demonstrate that most volunteers improved their knowledge related to antimicrobial resistance mechanisms in microbiology. Additional benefits of participation in this project included an improvement in dental knowledge and ethics in biomedical research for the student volunteers, whilst the student ambassadors reported improved knowledge about critical thinking and study design, as well as a deeper understanding about microbiological analysis methods. CONCLUSIONS: To the best of our knowledge, this the first instance of the application of project-based methodologies to the teaching of a traditionally non-laboratory component of a subject taught in the dentistry curriculum. Results from both students and ambassadors highlighted the increase in dental knowledge and an increased awareness of antimicrobial resistance as the key outcomes of this project.

Modulation of salivary cytokines in response to alcohol, tobacco and caffeine consumption: a pilot study.

It has been shown that long-term stimulant consumption alters the biological and microbiological status of the oral cavity. We present a pilot study describing stimulant-specific oral immunomodulation in the oral cavity. Changes in salivary cytokine levels in response to long-term alcohol, tobacco and caffeine were identified. Volunteers were recruited from amongst the patients visiting University Dental Clinic of CEU Cardenal Herrera University (Alfara del Patriarca, Spain). Participants were grouped according to their self-reported levels of consumption of either caffeine, alcohol or tobacco (control group volunteers were non-consumers of all three). Informed consent was provided and stimulated saliva samples were obtained and assayed for interleukin-1α IL-1α), Tumor Necrosis Factor α (TNF-α) and Interferon γ IFN-γ). Long-term, high-level consumers of alcohol or tobacco exhibited elevated salivary concentrations of the three inflammatory cytokines with respect to control values. Specifically, IL-1α was found to be elevated in alcohol users whilst IFN-γ concentration higher in tobacco users versus controls. Long-term caffeine consumers displayed elevated levels of IFN-γ and TNF-α, whereas IL-1α levels were reduced with respect to control volunteers. This pilot study demonstrates that salivary cytokines can be modulated in response to quantity and duration of alcohol, caffeine or tobacco consumption.

Effects of Polyacrylic Acid Pre-Treatment on Bonded-Dentine Interfaces Created with a Modern Bioactive Resin-Modified Glass Ionomer Cement and Subjected to Cycling Mechanical Stress.

OBJECTIVES: Resin-modified glass ionomer cements (RMGIC) are considered excellent restorative materials with unique therapeutic and anti-cariogenic activity. However, concerns exist regarding the use of polyacrylic acid as a dentine conditioner as it may influence the bonding performance of RMGIC. The aim of this study was to evaluate the effect of different protocols for cycling mechanical stress on the bond durability and interfacial ultramorphology of a modern RMGIC applied to dentine pre-treated with/without polyacrylic acid conditioner (PAA). METHODS: The RMGIC was applied onto human dentine specimens prepared with silicon-carbide (SiC) abrasive paper with or without the use of a PAA conditioner. The specimens were immersed in deionised water for 24 h then divided in 3 groups. The first group was cut into matchsticks (cross-sectional area of 0.9 mm2) and tested immediately for microtensile bond strength (MTBS). The second was first subjected to load cycling (250,000 cycles; 3 Hz; 70 N) and then cut into matchsticks and tested for MTBS. The third group was subjected to load cycling (250,000 cycles; 3 Hz; 70 N), cut into matchsticks, and then immersed for 8 months storage in artificial saliva (AS); these were finally tested for MTBS. The results were analysed statistically using two-way ANOVA and the Student⁻Newman⁻Keuls test (α = 0.05). Fractographic analysis was performed using FE-SEM, while further RMCGIC-bonded dentine specimens were aged as previously described and used for interfacial ultramorphology characterisation (dye nanoleakage) using confocal microscopy. RESULTS: The RMGIC applied onto dentine that received no pre-treatment (10% PAA gel) showed no significant reduction in MTBS after load cycling followed by 8 months of storage in AS (p > 0.05). The RMGIC⁻dentine interface created in PAA-conditioned SiC-abraded dentine specimens showed no sign of degradation, but with porosities within the bonding interface both after load cycling and after 8 months of storage in AS. Conversely, the RMGIC⁻dentine interface of the specimens with no PAA pre-treatment showed no sign of porosity within the interface after any of the aging protocols, although some bonded-dentine interfaces presented cohesive cracks within the cement after prolonged AS storage. However, the specimens of this group showed no significant reduction in bond strength (p < 0.05) after 8 months of storage in AS or load cycling (p > 0.05). After prolonged AS storage, the bond strength value attained in RMGIC⁻dentine specimens created in PAA pre-treated dentine were significantly higher than those observed in the specimens created with no PAA pre-treatment in dentine. CONCLUSIONS: PAA conditioning of dentine prior to application of RMGIC induces no substantial effect on the bond strength after short-term storage, but its use may increase the risk of collagen degradation at the bonding interface after prolonged aging. Modern RMGIC applied without PAA dentine pre-treatment may have greater therapeutic synergy with saliva during cycle occlusal load, thereby enhancing the remineralisation and protection of the bonding interface.

Falha de revascularização de um dente imaturo com cisto inflamatório / Revascularization failure of an immature tooth with inflammatory cyst

Objetivo: analisar as possíveis causas do insucesso de um tratamento de revascularização, incluindo as complicações derivadas da técnica e a adequada seleção do caso. Métodos: o seguinte relato de caso descreve o insucesso da revascularização de um segundo pré-molar inferior com ápice imaturo apresentando fístula e lesão periapical. A irrigação foi realizada com NaOCl, solução salina estéril e clorexidina, e uma pasta antibiótica composta por ciprofloxacina, metronidazol e cefaclor foi utilizada como medicamento intracanal. Uma vez que a fístula desapareceu, a hemorragia foi induzida pelo periápice. Como havia um sangramento residual, uma esponja de colágeno banhada de sangue foi colocada no canal e o acesso à cavidade foi selado com MTA. Resultados: após uma semana, a fístula reapareceu e uma cirurgia periapical foi realizada, com excisão da lesão. O diagnóstico final foi de uma lesão cística inflamatória. Após 12 meses, a regeneração óssea estava completa. Conclusões: o insucesso desse tratamento de revascularização pode ter sido devido à presença de uma lesão cística inflamatória. Ao se propor esse tipo de tratamento, o tamanho e o tempo de duração da lesão devem ser levados em consideração, informando ao paciente que a cirurgia periapical pode ser necessária.

Does Psychological Profile Influence Third Molar Extraction and Postoperative Pain?

PURPOSE: Our purposes were to determine the influence of psychological profile on hemodynamic changes in patients who undergo surgical removal of the third molars under intravenous sedation and to evaluate the effect on patients' anxiety and postoperative recovery. PATIENTS AND METHODS: We performed a prospective study of 100 patients (American Society of Anesthesiologists classes I and II; aged ≥18 years) seen in the CIMIVClinic (Department of Oral Surgery, Casa de Salud University Hospital, Valencia, Spain) who underwent extractions of all third molars under intravenous sedation. All patients were administered the Symptom Checklist 90 Revised (SCL-90-R). The following parameters were monitored at different times during the surgical interventions: systolic blood pressure, diastolic blood pressure, oxygen saturation, and heart rate. Position and depth of impaction of the tooth (Pell and Gregory classification and Winter classification), surgery duration, and surgical technique also were recorded. Finally, the degree of pain experienced the week after the surgical intervention was measured using a visual analog scale. RESULTS: Patients' anxiety levels preoperatively were significantly higher in patients with psychological distress (P = .023). Postoperative pain significantly decreased from the first day to the seventh day in healthy patients but not in patients with altered psychological conditions (P < .05). Nevertheless, the hemodynamic changes were not correlated with the psychological impairment. CONCLUSIONS: Intravenous sedation enables the control of hemodynamic changes in all patients independently of their psychological profile. Patients with psychological distress present with higher levels of dental anxiety and postoperative pain. Future studies are needed to further clarify this interaction.

[Municipal distribution and trend of the incidence of breast cancer in the health area of León, Spain (1996-2010)]. / Tendencia y distribución municipal de la incidencia de cáncer de mama en el área de salud de León (1996-2010).

BACKGROUND: Breast cancer is the most common amongst women. The aim of this study was to analyze the incidence and geographical distribution of breast cancer in the health area of León. METHODS: We designed an observational descriptive study that included women enrolled in the Hospital Tumor Registry of the Centro Asistencial Universitario in León with a diagnosis of breast malignant neoplasm (ICD-9: 174, ICD-10: 50) between 01/01/1996 and 31/12/2010 and resident in the health area of León. To study the spatial distribution, we estimated municipal relative risks (RR) smoothed by fitting the Besag, York and Mollié model and the posterior probability (PP) of RR > 1 using Bayesian methods. RESULTS: A total of 2379 cases were included. The number of new cases and the crude incidence rate have both increased in every triennium, from 72,7 (1996-1998) to 101,5 (2008-2010) per 100,000 women. The age adjusted rates per 100,000 women (European standard population) increased from 58,0 during the first triennium to 69,4 during the last one. An average annual increase of 1,3% was observed. Several municipalities from the health area of León showed risks higher than a 10%. The PP were higher than 0.9 only in the municipality of León. CONCLUSION: The observed rates are among the lowest in our country. Nevertheless, the number of cases and the incidence rates have increased progressively.

Tendencia y distribución municipal de la incidencia de cáncer de mama en el área de salud de León (1996-2010) (AU) / Municipal distribution and trend of the incidence of breast cancer in the health area of León, Spain (1996-2010)

Fundamentos: El cáncer de mama es el más frecuente en las mujeres. El objetivo del presente estudio fue analizar la incidencia y distribución geográfica del cáncer de mama invasivo en el área de salud de León (ASL). Métodos: Estudio observacional descriptivo en el que se incluyeron mujeres con diagnóstico de neoplasia maligna de mama (CIE-9:174, CIE-10:C50) del Registro Hospitalario de Tumores del Centro Asistencial Universitario de León, entre 1/1/1996 y 31/12/2010 y con residencia en el ASL. Para el análisis de la distribución espacial se estimaron los riesgos relativos (RR) municipales suavizados mediante el ajuste del modelo de Besag, York y Mollié y sus probabilidades posteriores de que los RR fuesen >1 (PP), utilizando métodos bayesianos. Resultados: Se incluyó un total de 2.379 casos. El número de casos nuevos y las tasas de incidencia brutas en cada trienio fueron de 72,7 (1996-1998) a 101,5 (2008-2010) por 100.000 mujeres. Las tasas a población europea por 100.000 mujeres ascendieron de 58,0 en el primer trienio y a 69,4 en el último. Se observó un incremento anual promedio del 1,3 %. Varios municipios del ASL presentaron riesgos superiores al 10 %. Las PP solo fueron superiores a 0,9 en el municipio de León. Conclusiones: Las tasas observadas son de las más bajas de España. Sin embargo, el número de casos y las tasas de incidencia se incrementaron de manera mantenida en el periodo estudiado (AU)

Background: Breast cancer is the most common amongst women. The aim of this study was to analyze the incidence and geographical distribution of breast cancer in the health area of León. Methods: We designed an observational descriptive study that included women enrolled in the Hospital Tumor Registry of the Centro Asistencial Universitario in León with a diagnosis of breast malignant neoplasm (ICD-9:174, ICD-10:50) between 01/01/1996 and 31/12/2010 and resident in the health area of León. To study the spatial distribution, we estimated municipal relative risks (RR) smoothed by fitting the Besag, York and Mollié model and the posterior probability (PP) of RR > 1 using Bayesian methods. Results: A total of 2379 cases were included. The number of new cases and the crude incidence rate have both increased in every triennium, from 72,7 (1996-1998) to 101,5 (2008-2010) per 100,000 women. The age adjusted rates per 100,000 women (European standard population) increased from 58,0 during the first triennium to 69,4 during the last one. An average annual increase of 1,3 % was observed. Several municipalities from the health area of León showed risks higher than a 10 %. The PP were higher than 0.9 only in the municipality of León. Conclusion: The observed rates are among the lowest in our country. Nevertheless, the number of cases and the incidence rates have increased progressively (AU)

A survey of oral surgeons’ tobacco-use-related knowledgeand intervention behaviors

Objectives: To evaluate whether oral surgeons are aware of tobacco’s role in oral health. Moreover, we wanted to know professionals’ attitudes towards smoker patients and physicians’ involvement in detecting and eradicating this habit in patients.Study Design: We conducted a survey to determine the awareness of the members of the Spanish Society of Oral Surgery about tobacco’s damage on oral health and the role of dentists in the prevention and elimination of the smoking habit. Results: 450 surveys were distributed during the Seventh National Congress of the Spanish Society of Oral Surgery, of which 224 (49.8%) were answered. Seventy-six point eight percent of oral surgeons said that they have a good knowledge of the effects of snuff on oral health. However, only 42.9% admitted they had received specific training regarding how to deal with patients who want to give up smoking. Sixty-three point four percent had explained to smoker patients the risk of this habit for the oral and general health. However, 17% admitted they do not advise their patients to give up smoking for fear of upsetting them, while 15.2% expressed lack of time, and 3.6% think it is not their competence. As to the relationship between oral cancer and smoking, 83% of oral surgeons recognize a direct relationship. In addition, 85.7% of professionals believe that dentists have a primary role in oral cancer prevention. Conclusions: These results indicate that most oral surgeons are concerned about the smoking habit of their patients. However, it is necessary to increase the specific training of dentists by providing tobacco treatment programs as part of their professional responsibility. Oral surgeons recognize the direct relationship between the smoking habit and oral cancer and regard as very important the role of dentists in the prevention of this disease (AU)

Antibiotic prescription in the treatment of odontogenic infection by health professionals: A factor to consensus

Objective: To observe the attitude of dentists and family doctors in prescribing antibiotics for the treatment of dental infections. Study Design: A poll was performed to determine the differences in the prescription of antibiotics for the treatment of odontogenic infection by dentists and family doctors of the primary care department of the Catalan Health Care Service.Results: A hundred polls were distributed among family doctors, and another 100 ones among primary care dentists assigned to the Catalan Health Care Service of the Generalitat de Catalunya. Of the total of questionnaires distributed, 63 were retuned and answered from dentists and 71 from family doctors. Eighty-one percent of dentists included in the opinion poll considered amoxicillin as the first antibiotic choice for the treatment of odontogenic infections, while 73.2% of family doctors preferred the combination of amoxicillin and clavulanic acid. With regard to antibiotics of choice in patients allergic to penicillin, 67.7% of family doctors preferred macrolides (25.4% opted for clarithromycin, 25.4% for erythromycin and 16.9% for spiramycin). However, clindamycin was the antibiotic most frequently prescribed by dentists (66.7%), followed by erythromycin (28.6%).Conclusions: The results of this study show a large discrepancy in the criteria for the treatment of odontogenic infections on the part of leading professionals involved in the management of this condition. Although the most common prescription involved beta-lactam antibiotics in both groups, several significant differences have been detected with regard to the second antibiotic choice (AU)

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A survey of oral surgeons' tobacco-use-related knowledge and intervention behaviors.

OBJECTIVES: To evaluate whether oral surgeons are aware of tobacco' s role in oral health. Moreover, we wanted to know professionals' attitudes towards smoker patients and physicians' involvement in detecting and eradicating this habit in patients. STUDY DESIGN: We conducted a survey to determine the awareness of the members of the Spanish Society of Oral Surgery about tobacco' s damage on oral health and the role of dentists in the prevention and elimination of the smoking habit. RESULTS: 450 surveys were distributed during the Seventh National Congress of the Spanish Society of Oral Surgery, of which 224 (49.8%) were answered. Seventy-six point eight percent of oral surgeons said that they have a good knowledge of the effects of snuff on oral health. However, only 42.9% admitted they had received specific training regarding how to deal with patients who want to give up smoking. Sixty-three point four percent had explained to smoker patients the risk of this habit for the oral and general health. However, 17% admitted they do not advise their patients to give up smoking for fear of upsetting them, while 15.2% expressed lack of time, and 3.6% think it is not their competence. As to the relationship between oral cancer and smoking, 83% of oral surgeons recognize a direct relationship. In addition, 85.7% of professionals believe that dentists have a primary role in oral cancer prevention. CONCLUSIONS: These results indicate that most oral surgeons are concerned about the smoking habit of their patients. However, it is necessary to increase the specific training of dentists by providing tobacco treatment programs as part of their professional responsibility. Oral surgeons recognize the direct relationship between the smoking habit and oral cancer and regard as very important the role of dentists in the prevention of this disease.

Antibiotic prescription in the treatment of odontogenic infection by health professionals: a factor to consensus.

OBJECTIVE: To observe the attitude of dentists and family doctors in prescribing antibiotics for the treatment of dental infections. STUDY DESIGN: A poll was performed to determine the differences in the prescription of antibiotics for the treatment of odontogenic infection by dentists and family doctors of the primary care department of the Catalan Health Care Service. RESULTS: A hundred polls were distributed among family doctors, and another 100 ones among primary care dentists assigned to the Catalan Health Care Service of the Generalitat de Catalunya. Of the total of questionnaires distributed, 63 were retuned and answered from dentists and 71 from family doctors. Eighty-one percent of dentists included in the opinion poll considered amoxicillin as the first antibiotic choice for the treatment of odontogenic infections, while 73.2% of family doctors preferred the combination of amoxicillin and clavulanic acid. With regard to antibiotics of choice in patients allergic to penicillin, 67.7% of family doctors preferred macrolides (25.4% opted for clarithromycin, 25.4% for erythromycin and 16.9% for spiramycin). However, clindamycin was the antibiotic most frequently prescribed by dentists (66.7%), followed by erythromycin (28.6%). CONCLUSIONS: The results of this study show a large discrepancy in the criteria for the treatment of odontogenic infections on the part of leading professionals involved in the management of this condition. Although the most common prescription involved beta-lactam antibiotics in both groups, several significant differences have been detected with regard to the second antibiotic choice.