Assessment of infection control in oral radiology during the COVID-19 outbreak: An international collaborative study.

Purpose: In the context of COVID-19, studies evaluating the adherence of dentists and dental students to infection control are relevant due to their high occupational exposure and risk, as well as their responsibility for disseminating information and good practices. This study evaluated the adherence of dentists and dental students to infection control in the oral radiology field in the setting of the COVID-19 pandemic on different continents. Materials and Methods: This cross-sectional observational study involved individuals who performed intraoral radiographic examinations during the COVID-19 pandemic. The Questionnaire on Infection Control in Oral Radiology was administered virtually using a Google Form. Participants from different continents (the Americas, Africa, Europe, Asia, and Oceania) were recruited. Data were subjected to descriptive analysis and simple and multiple binary regression (5%). Results: There were 582 valid answers, and 68.73% of the participants were from the Americas, 18.90% from Europe, and 12.37% from Asia. The median score for infection control protocols was 94 points for dental students and 104 points for dentists, and participants below the median were considered to have low adherence to infection control in oral radiology. Low access to infection control was found for 53.0% of dentists in the Americas, 34.0% from Europe, and 26.9% from Asia. Conclusion: The adherence to infection control protocols in oral radiology was low even in the face of the COVID-19 pandemic. The results may help improve the awareness of students and professionals, since oral radiology routines have the potential for transmitting COVID-19.

Radiographic Diagnosis of Simulated External Root Resorption in Multi-Rooted Teeth: The Influence of Spatial Resolution.

The aim of this study was to evaluate the influence of spatial resolution (line pairs per millimetre - lp/mm) on the diagnosis of simulated external root resorption (ERR) in multi-rooted teeth by using digital periapical radiography. Forty human mandibular molars (80 roots) were used. The roots were divided into the following groups (n = 10): control without root filling (WORF), control with root filling (WRF), small ERRWORF, small ERR-WRF, moderate ERR-WORF, moderate ERR-WRF, extensive ERR-WORF and extensive ERR-WRF. Four digital radiographs (phosphor storage plates - PSP system) were taken of each tooth in three angulations. The PSPs were scanned with 10, 20, 25 and 40 lp/mm. All images were assessed by three endodontists who used a five-point scale for presence and absence of ERR and classified its location (cervical, middle or apical third). ROC curves and one-way ANOVA were performed (p < 0.01). Diagnosis of ERR in nonroot-filled teeth showed higher values of sensitivity for 20 lp/mm and higher values of both specificity and accuracy for 40 lp/mm. In root-filled teeth, sensitivity and accuracy were higher for 25 lp/mm and spatial resolution had no influence on specificity. The best resolution for diagnosis of small and extensive ERR was 25 lp/mm, whereas for moderate ERR, it was 40 lp/mm. Cervical ERR was the most difficult to diagnose, regardless of the spatial resolution. Higher spatial resolutions have improved the radiographic diagnosis of simulated ERR in multi-rooted teeth and this should be considered when performing digital radiographs.

O objetivo deste estudo foi avaliar a influência do número de pares de linhas em radiografia intra-oral digital, na precisão da detecção de reabsorção radicular externa. Quarenta molares inferiores (n=80 raízes) foram submetidos ao preparo químico mecânico e em então, metade da amostra foi obturada. Em seguida, as raízes dos dentes foram aleatoriamente divididas de acordo com o tamanho da reabsorção radicular a ser simulada e com a presença e ausência de tratamento endodôntico. As RRE foram realizadas com brocas esféricas diamantadas de tamanhos 1/2, 1, 2. Executou-se radiografias digitais por meio do sistema de aquisição semidireto com a utilização de placas de fósforo fotoestimuladas (PSP). Em cada dente, incidências orto, mésio e distorradial foram repetidas quatro vezes, para que pudessem ser digitalizadas com resoluções de 10, 20, 25, 40 pl/mm. Após análise, verificou-se que dentes obturados apresentaram menores valores de sensibilidade com 10, 20 e 25 pl/mm e maiores valores de especificidade e acurácia para as mesmas resoluções. Dentes sem obturação registraram maiores valores de sensibilidade para resolução 20 e menor para 40; no entanto, a especificidade e a acurácia, foram maiores com 40 e menores em 10. Em RRE pequena, as resoluções 10 e 25 pl/mm foram respectivamente menos e mais acuradas; RRE média, foi maior com 40 pl/mm e RRE grandes foram melhores identificadas com 25. Correlacionando acertos no diagnóstico com localização das RRE, verificou-se que o terço cervical apresentou-se menos detectável. Concluiu-se que resolução espacial influenciou a detecção de RRE simuladas em radiografias periapicais digitais.

Radiographic Diagnosis of Simulated External Root Resorption in Multi-Rooted Teeth: The Influence of Spatial Resolution / Diagnóstico radiográfico de reabsorção externa simulada em dentes multiradiculares: influência da resolução especial

ABSTRACT The aim of this study was to evaluate the influence of spatial resolution (line pairs per millimetre - lp/mm) on the diagnosis of simulated external root resorption (ERR) in multirooted teeth by using digital periapical radiography. Forty human mandibular molars (80 roots) were used. The roots were divided into the following groups (n = 10): control without root filling (WORF), control with root filling (WRF), small ERRWORF, small ERRWRF, moderate ERRWORF, moderate ERRWRF, extensive ERRWORF and extensive ERRWRF. Four digital radiographs (phosphor storage plates - PSP system) were taken of each tooth in three angulations. The PSPs were scanned with 10, 20, 25 and 40 lp/mm. All images were assessed by three endodontists who used a fivepoint scale for presence and absence of ERR and classified its location (cervical, middle or apical third). ROC curves and oneway ANOVA were performed (p < 0.01). Diagnosis of ERR in nonrootfilled teeth showed higher values of sensitivity for 20 lp/mm and higher values of both specificity and accuracy for 40 lp/mm. In rootfilled teeth, sensitivity and accuracy were higher for 25 lp/mm and spatial resolution had no influence on specificity. The best resolution for diagnosis of small and extensive ERR was 25 lp/mm, whereas for moderate ERR, it was 40 lp/mm. Cervical ERR was the most difficult to diagnose, regardless of the spatial resolution. Higher spatial resolutions have improved the radiographic diagnosis of simulated ERR in multirooted teeth and this should be considered when performing digital radiographs.

RESUMO O objetivo deste estudo foi avaliar a influência do número de pares de linhas em radiografia intraoral digital, na precisão da detecção de reabsorção radicular externa. Quarenta molares inferiores (n=80 raízes) foram submetidos ao preparo químico mecânico e em então, metade da amostra foi obturada. Em seguida, as raízes dos dentes foram aleatoriamente divididas de acordo com o tamanho da reabsorção radicular a ser simulada e com a presença e ausência de tratamento endodôntico. As RRE foram realizadas com brocas esféricas diamantadas de tamanhos 1/2, 1, 2. Executouse radiografias digitais por meio do sistema de aquisição semidireto com a utilização de placas de fósforo fotoestimuladas (PSP). Em cada dente, incidências orto, mésio e distorradial foram repetidas quatro vezes, para que pudessem ser digitalizadas com resoluções de 10, 20, 25, 40 pl/mm. Após análise, verificouse que dentes obturados apresentaram menores valores de sensibilidade com 10, 20 e 25 pl/mm e maiores valores de especificidade e acurácia para as mesmas resoluções. Dentes sem obturação registraram maiores valores de sensibilidade para resolução 20 e menor para 40; no entanto, a especificidade e a acurácia, foram maiores com 40 e menores em 10. Em RRE pequena, as resoluções 10 e 25 pl/mm foram respecti vamente menos e mais acuradas; RRE média, foi maior com 40 pl/mm e RRE grandes foram melhores identificadas com 25. Correlacionando acertos no diagnóstico com localização das RRE, verificouse que o terço cervical apresentouse menos detectável. Concluiuse que resolução espacial influenciou a detecção de RRE simuladas em radiografias periapicais digitais.

Evaluation of Radiopacity of Luting Cements Submitted to Different Aging Procedures.

PURPOSE: To evaluate the radiopacity of luting cements submitted to different aging procedures. MATERIALS AND METHODS: Twenty discs (1 × 4 mm) of each of the following cements were prepared: zinc phosphate, RelyX Luting 2, Variolink 2, AllCem, RelyX U200, Multilink, Panavia F2.0, and RelyX ARC. Then, they were randomly divided into two groups (n = 10/group), according to the aging procedure: thermal cycling group and water storage group. Before and after aging procedures, specimens were x-rayed with an aluminum step-wedge (11 steps, 1 mm thick each) and three dental slices (1 mm thick). The radiopacity was evaluated by means of optical density, which was measured using ImageJ software. The values were converted into millimeters of aluminum with a logistic regression calibration curve. The data were analyzed by one-way ANOVA and Tukey post-hoc test (α = 0.05). RESULTS: In the thermal cycling group, RelyX Luting 2, RelyX U200, and Panavia F2.0 showed a statistically significant reduction in radiopacity (p < 0.05). In the water storage group, all cements showed a significant reduction in radiopacity (p < 0.05), and RelyX Luting 2 and Panavia F2.0 performed below the desired ISO 4049 standard. CONCLUSIONS: The radiopacity of luting cements can decrease after aging, especially after 1-year water storage.