Aesthetic perception of single implants placed in the anterior zone. A cross-sectional study

Background: Several aesthetic indexes have been described to assess implant aesthetics. The aim of this study was to compare the aesthetic assessment made by dental professionals and students of single-tooth implants placed in the upper incisors. Materials and methods: A cross-sectional survey study using a subjective questionnaire to assess the aesthetics in 3 implant supported single-tooth cases in the anterior maxilla was performed. The interviewed subjects were divided into 4 groups: dentist with experience in implant treatment, dentists without experience in implants and 3rd and 5th year dental students. The questionnaire consisted of 2 visual analogue scales (VAS) to evaluate aesthetics, the pink esthetic score (PES), the white esthetic score (WES) and the simplified papilla index (PI). Results: One-hundred dentists and one-hundred dental students filled the aesthetic assessment questionnaire. The results showed that the subjects were more critical than reference values, specially concerning prosthetic issues. The differences between groups were more obvious in the case with the best result. On the other hand, few differences were detected in the remaining cases. Regarding soft tissue and crown features, experienced dentists in implant dentistry were the most demanding. Cronbach's Alpha showed values ≥ 0,8 in the questionnaire in every case, which indicates an adequate reliability. Conclusions: Dentists and dental students have different opinions when assessing aesthetics of single tooth implant supported cases. Experience and area of expertise seem to influence the evaluation of aesthetics in the anterior region

Microbiota analysis of biofilms on experimental abutments mimicking dental implants: an in vivo model

Background: the microbiota colonizing dental implants has been said to be similar to the microbiome surrounding teeth. In the absence of inflammation, a biofilm with pathologic bacteria can cover implant surfaces exposed to the oral cavity, for example, due to a remodeling process. The aim of the present study is to identify microbiota surrounding exposed dental implants in patients with and without a history of periodontitis through a deep-sequencing approach. Methods: an experimental abutment with the same surface and structure as a commercially available dental implant was used. Bacterial DNA was isolated, and the 16S ribosomal RNA gene was amplified and sequenced. Multiplexed tag-encoded sequencing of DNA from the samples was performed, and the reads were processed by metagenomic rapid annotation.Results: a wide variety of bacteria, 96 species, were identified. The most frequently found bacteria were Fusobacterium nucleatum and Prevotella denticola. Some species generally associated with periodontitis were found to a greater extent in patients without a history of periodontitis. Some bacteria that have never been described as part of the oral microbiome were identified in the present sample.Conclusions: analysis of data suggests that the bacteria surrounding exposed dental implants form a diverse microbiome regardless of the periodontal profile of patients. Further research is needed to clarify the role of these microorganisms in the oral environment

The COVID-19 pandemic and its global effects on dental practice : An International survey

Objectives: A multicentre survey was designed to evaluate the impact of COVID-19 outbreak on dental practice worldwide, estimate the COVID-19 related symptoms/signs, work attitudes and behaviour and the routine use of protective measures and Personal Protective Equipment (PPE). Methods: A global survey using a standardized questionnaire with research groups from 36 countries was designed. The questionnaire was developed and pretested during April 2020 and contained three domains: 1) Personal data; 2) COVID-19 positive rate and symptoms/signs presumably related to the coronavirus; 3) Working conditions and PPE adopted after the outbreak. Countries' data were grouped by the Country Positive Rate (CPR) during the survey period and by Gross-National-Income per capita. An ordinal multinomial logistic regression model was carried out with COVID-19 self-reported rate referred by dental professionals as dependent variable to assess the association with questionnaire items. Results: A total of 52,491 questionnaires were returned with a male/female ratio of 0.63. Out of the total respondents, 7,859 dental professionals (15%) reported symptoms/signs compatible with COVID-19. More than half of the sample (n = 27,818; 53%) stated to use FFP2/N95 masks, while 21,558 (41.07%) used eye protection. In the bivariate analysis, CPR and N95/FFP2 were significantly associated (OR = 1.80 95% =5.20 95% 95% CI = 1.60/2.82 and OR CI = 1.44/18.80, respectively), while Gross-National-Income was not statistically associated with CPR (OR = 1.09 CI = 0.97/1.60). The same significant associations were observed in the multivariate analysis. Conclusions: Oral health service provision has not been significantly affected by COVID-19, although access to routine dental care was reduced due to country-specific temporary lockdown periods. While the dental profession has been identified at high-risk, the reported rates of COVID-19 for dental professionals were not significantly different to those reported for the general population in each country. These findings may help to better plan oral health care for future pandemic events

Características del biofilm oral formado sobre implantes dentales

[spa] Desde hace más de 30 años, los implantes osteointegrados son una alternativa viable para el reemplazo de las ausencias dentarias, con un alto porcentaje de supervivencia y éxito. Sin embargo, la prevalencia de sus complicaciones biológicas no es despreciable. Se estima que entre un 12 y un 22% de los pacientes portadores de implantes padece de periimplantitis (PI), una alteración que se caracteriza por la presencia de inflamación y pérdida ósea periimplantaria. Puesto que se trata de una enfermedad inflamatoria en que las bacterias desempeñan un papel muy relevante, es interesante estudiar cómo se organizan éstas sobre la superficie de los implantes. La microbiota que coloniza los implantes dentales hasta ahora se ha considerado similar a la microbiota encontrada alrededor de dientes. En ausencia de inflamación, por ejemplo, tras un proceso de remodelado óseo, la superficie del implante queda expuesta al medio oral permitiendo el acúmulo de placa bacteriana. Para conocer más en profundidad cómo es este biofilm formado sobre la superficie expuesta de un implante dental, se diseñaron los 2 estudios que componen la presente tesis doctoral. El primer estudio tenía como objetivo principal determinar si un pilar experimental, que simula la macro y microestructura de un implante, es un método adecuado para recoger biofilm oral. Además, también pretendió describir las características del biofilm formado sobre estos pilares. Para ello, se colocaron pilares experimentales en 15 pacientes portadores de implantes sin patología periimplantaria. Tras 14 días, los aditamentos fueron analizados con microscopía confocal y electrónica de barrido. Los 5 primeros pilares se tiñeron para determinar la cantidad de biomasa que colonizaba los aditamentos y los 10 restantes con una tinción que permitiera además diferenciar células vivas de células muertas. Se observó un recubrimiento global de los pilares en todos los pacientes. El área supragingival mostró un mayor porcentaje de recubrimiento (38%) en comparación con el área subgingival (21%) y la ratio de bacterias vivas/muertas también fue ligeramente mayor en la zona supragingival (p<0.074). El segundo estudio pretendía identificar la composición de la microbiota formada alrededor de implantes expuestos a la cavidad bucal utilizando técnicas de metagenómica. El pilar experimental descrito anteriormente se empleó para recoger el biofilm de 10 pacientes portadores de implantes sanos. Transcurridos 14 días, se analizó dicho biofilm mediante un proceso de pirosecuenciación del gen 16S. Se identificaron un total de 96 especies y las bacterias más frecuentemente encontradas fueron Fusobacterium nucleatum y Prevotella denticola. Algunas de las especies que generalmente se asocian a la periodontitis se encontraron en mayor medida en aquellos pacientes que no tenían antecedentes de periodontitis. Además, se identificaron algunas bacterias que nunca habían sido descritas como parte del microbioma oral. Se puede concluir que la utilización de pilares experimentales removibles permite recoger y estudiar el biofilm formado sobre implantes dentales. Por otro lado, tras 14 días de exposición a la cavidad bucal, la mayoría de la superficie de los implantes se cubrirá por un biofilm maduro y espeso compuesto por una microbiota heterogénea con predominio de Fusobacterium nucleatum y Prevotella denticola. Además, la cantidad y distribución del biofilm formado sobre un implante tras 14 días.[eng] Peri-implant diseases are oral diseases caused by a biofilm infection in a susceptible individual. This entity comprises two major pathologies; peri-implant mucositis and peri-implantitis. The prevalence of peri-implantitis given in private practice ranges from 12% to 22% of patients, and 39% of patients with mucositis at 5 years in media. Microbiota colonizing dental implants has been considered to be similar that microbiota observed around teeth. In absence of inflammation, i.e after a remodeling process, the surface of a dental implant can get exposed to the oral cavity and it will be colonized by a biofilm. The present thesis has two objectives. Firstly, to determine whether an experimental abutment mimicking the macro and microstructure of a dental implant is a suitable method for recovering biofilm, and to describe the features of biofilms formed around such abutments on healthy implants. Secondly, to identify microbiota surrounding exposed dental implants in patients with and without a history of periodontitis through a deep-sequencing approach. An experimental abutment with the same surface and structure as a commercially available dental implant was used. After 14 days’ absence of dental hygiene in this area, the abutments were retrieved and analyzed through a deep-sequencing approach in the first study. In the second study, the abutments used were studied through confocal laser scanning microscopy and with a scanning electron microscope. The results obtained from the first study showed a wide variety of bacteria, 96 species, were identified. The most frequently found bacteria were Fusobacterium nucleatum and Prevotella denticola. Some species generally associated with periodontitis were found to a greater extent in patients without a history of periodontitis. Some bacteria that have never been described as part of the oral microbiome were identified in the present sample. The second study showed a global plaque coverage of the abutments was observed in all cases. The submucosal area of the abutment was mostly covered with biofilm (over 21%). Moreover, significant differences between supra- and subgingival locations were detected. The ratio of live to dead bacteria was slightly higher in the supragingival portion of the abutment than in the subgingival part (p<0.074)

Microbiota analysis of biofilms on experimental abutments mimicking dental implants: an in vivo model

Background: the microbiota colonizing dental implants has been said to be similar to the microbiome surrounding teeth. In the absence of inflammation, a biofilm with pathologic bacteria can cover implant surfaces exposed to the oral cavity, for example, due to a remodeling process. The aim of the present study is to identify microbiota surrounding exposed dental implants in patients with and without a history of periodontitis through a deep-sequencing approach. Methods: an experimental abutment with the same surface and structure as a commercially available dental implant was used. Bacterial DNA was isolated, and the 16S ribosomal RNA gene was amplified and sequenced. Multiplexed tag-encoded sequencing of DNA from the samples was performed, and the reads were processed by metagenomic rapid annotation.Results: a wide variety of bacteria, 96 species, were identified. The most frequently found bacteria were Fusobacterium nucleatum and Prevotella denticola. Some species generally associated with periodontitis were found to a greater extent in patients without a history of periodontitis. Some bacteria that have never been described as part of the oral microbiome were identified in the present sample.Conclusions: analysis of data suggests that the bacteria surrounding exposed dental implants form a diverse microbiome regardless of the periodontal profile of patients. Further research is needed to clarify the role of these microorganisms in the oral environment

Microbiota analysis of biofilms on experimental abutments mimicking dental implants: an in vivo model

Background: the microbiota colonizing dental implants has been said to be similar to the microbiome surrounding teeth. In the absence of inflammation, a biofilm with pathologic bacteria can cover implant surfaces exposed to the oral cavity, for example, due to a remodeling process. The aim of the present study is to identify microbiota surrounding exposed dental implants in patients with and without a history of periodontitis through a deep-sequencing approach. Methods: an experimental abutment with the same surface and structure as a commercially available dental implant was used. Bacterial DNA was isolated, and the 16S ribosomal RNA gene was amplified and sequenced. Multiplexed tag-encoded sequencing of DNA from the samples was performed, and the reads were processed by metagenomic rapid annotation.Results: a wide variety of bacteria, 96 species, were identified. The most frequently found bacteria were Fusobacterium nucleatum and Prevotella denticola. Some species generally associated with periodontitis were found to a greater extent in patients without a history of periodontitis. Some bacteria that have never been described as part of the oral microbiome were identified in the present sample.Conclusions: analysis of data suggests that the bacteria surrounding exposed dental implants form a diverse microbiome regardless of the periodontal profile of patients. Further research is needed to clarify the role of these microorganisms in the oral environment