A Contemporary Evaluation on Posterior Direct Restoration Teaching among Undergraduates in Dental Schools in Malaysia.

There is a current trend to restore posterior teeth with composite resin due to increasing demands on natural tooth colour restoration and increased concern about the safety of amalgam restorations. The objective was to evaluate the current teaching of posterior direct restoration among restorative dental lecturers in Malaysia compared to available international literature. An online questionnaire, which sought information on the teaching of posterior restoration was developed and distributed to 13 dental schools in Malaysia. The response rate for the questionnaire was 53.8%. The most popular posterior restoration teaching methods among the respondents were lecture (95.7%), demonstration (87.0%) and problem-based learning (PBL) (73.9%), while continuous assessment and a practical competency test (82.6%) were the most popular assessment methods. Placing a hard setting calcium hydroxide and GIC base for deep cavity restored by composite restoration was taught in 79.2% of cases. The standard protocols for posterior composite restoration were incremental filling in deep cavity (87.5%), using circumferential metal bands with wooden wedge (91.7%), with a total etch system (95.8%), using a light emitting diode (LED) light curing unit (91.7%), finishing using water cooling (80%) and finishing with a disc (87.5%). Graduates from dental schools in Malaysia received similar theoretical, preclinical and clinical teaching on posterior restoration techniques, although there were variations in the delivery methods, techniques and assessments, pointing to a need for uniformity and consensus.

Shape-based interpolation method in measuring intracranial volume for pre- and post-operative decompressive craniectomy using open source software / Método de interpolación basado en formas para medir el volumen intracraneal en craneotomía descompresiva pre y postoperatoria utilizando un software de código abierto

Introduction: Intracranial volume (ICV) is an important tool in the management of patients undergoing decompressive craniectomy (DC) surgery. The aim of this study was to validate ICV measurement applying the shape-based interpolation (SBI) method using open source software on computed tomography (CT) images. Methods: The pre- and post-operative CT images of 55 patients undergoing DC surgery were analyzed. The ICV was measured by segmenting every slice of the CT images, and compared with estimated ICV calculated using the 1-in-10 sampling strategy and processed using the SBI method. An independent t test was conducted to compare the ICV measurements between the two different methods. The calculation using this method was repeated three times for reliability analysis using the intraclass correlations coefficient (ICC). The Bland-Altman plot was used to measure agreement between the methods for both pre- and post-operative ICV measurements. Results: The mean ICV (±SD) were 1341.1±122.1ml (manual) and 1344.11±122.6ml (SBI) for the preoperative CT data. The mean ICV (±SD) were 1396.4±132.4ml (manual) and 1400.53±132.1ml (SBI) for the post-operative CT data. No significant difference was found in ICV measurements using the manual and the SBI methods (p=.983 for pre-op, and p=.960 for post-op). The intrarater ICC showed a significant correlation; ICC=1.00. The Bland-Altman plot showed good agreement between the manual and the SBI method. Conclusion: The shape-based interpolation method with 1-in-10 sampling strategy gave comparable results in estimating ICV compared to manual segmentation. Thus, this method could be used in clinical settings for rapid, reliable and repeatable ICV estimations

Introducción: El volumen intracraneal (ICV) constituye una importante herramienta para el tratamiento de los pacientes sometidos a craneotomía descompresiva (CD). El objetivo de este estudio fue validar la medición del ICV aplicando el método de interpolación basado en formas (SBI), utilizando software de código abierto en las imágenes de tomografía computarizada (TC). Métodos: Se analizaron las imágenes pre- y postoperatorias de TC de 55 pacientes sometidos a CD. Se midió el ICV segmentando cada corte de las imágenes de TC, comparándose con el ICV estimado calculado utilizando la estrategia de muestreo 1 de 10, y procesándose mediante el método SBI. Se realizó una prueba t independiente para comparar las mediciones de ICV entre los 2 métodos. Se repitió 3 veces el cálculo con este método, para realizar el análisis de fiabilidad, utilizando el coeficiente de correlación intra-clase (ICC). Se utilizó el gráfico de Bland-Altman para medir el acuerdo entre ambos métodos, para las mediciones de ICV pre- y postoperatorias. Resultados: El ICV medio (±DE) fue de 1.341,1ml±122,1 (manual) y 1.344,11ml±122,6 (SBI) para los datos de la TC preoperatoria. El ICV medio (±DE) fue de 1.396,4ml±132,4 (manual) y 1.400,53ml±132,1 (SBI) para los datos de la TC postoperatoria. No se encontró diferencia significativa en cuanto a las mediciones de ICV utilizando los métodos manual y SBI (p=0,983 para preoperatoria, p=0,960 para postoperatoria). El ICC intra-evaluador reflejó una correlación significativa; ICC=1. El gráfico de Bland-Altman reflejó un buen acuerdo entre el método manual y el método SBI. Conclusión: El método de interpolación basado en formas con estrategia de muestreo 1 de 10 proporcionó resultados comparables a la hora de calcular el ICV, en comparación con la segmentación manual. Por tanto, este método podría utilizarse en el entorno clínico para realizar estimaciones del ICV rápidas, fidedignas y repetibles

Shape-based interpolation method in measuring intracranial volume for pre- and post-operative decompressive craniectomy using open source software.

INTRODUCTION: Intracranial volume (ICV) is an important tool in the management of patients undergoing decompressive craniectomy (DC) surgery. The aim of this study was to validate ICV measurement applying the shape-based interpolation (SBI) method using open source software on computed tomography (CT) images. METHODS: The pre- and post-operative CT images of 55 patients undergoing DC surgery were analyzed. The ICV was measured by segmenting every slice of the CT images, and compared with estimated ICV calculated using the 1-in-10 sampling strategy and processed using the SBI method. An independent t test was conducted to compare the ICV measurements between the two different methods. The calculation using this method was repeated three times for reliability analysis using the intraclass correlations coefficient (ICC). The Bland-Altman plot was used to measure agreement between the methods for both pre- and post-operative ICV measurements. RESULTS: The mean ICV (±SD) were 1341.1±122.1ml (manual) and 1344.11±122.6ml (SBI) for the preoperative CT data. The mean ICV (±SD) were 1396.4±132.4ml (manual) and 1400.53±132.1ml (SBI) for the post-operative CT data. No significant difference was found in ICV measurements using the manual and the SBI methods (p=.983 for pre-op, and p=.960 for post-op). The intrarater ICC showed a significant correlation; ICC=1.00. The Bland-Altman plot showed good agreement between the manual and the SBI method. CONCLUSION: The shape-based interpolation method with 1-in-10 sampling strategy gave comparable results in estimating ICV compared to manual segmentation. Thus, this method could be used in clinical settings for rapid, reliable and repeatable ICV estimations.

Addition of zygomatic arch resection in decompressive craniectomy.

Decompressive craniectomy (DC) is a surgical option in managing uncontrolled raised intracranial pressure refractory to medical therapy. The authors evaluate the addition of zygomatic arch (ZA) resection with standard DC and analyze the resulting increase in brain volume using three-dimensional volumetric CT scans. Measurements of brain expansion dimension morphometrics from CT images were also analyzed. Eighteen patients were selected and underwent DC with ZA resection. The pre- and post-operative CT images were analyzed for volume and dimensional changes. CT images of 29 patients previously operated on at the same center were retrieved from the picture archiving and communication system (PACS) and were similarly studied. The findings obtained from the two groups were compared and analyzed. Analysis from three-dimensional CT volumetric techniques revealed an significant increase of 27.97ml (95% confidence interval [CI]: 39.98-180.36; p=0.048) when compared with standard DC. Brain expansion analysis of maximum hemicraniectomy diameter revealed a mean difference of 0.82cm (95% CI: 0.25-1.38; p=0.006). Analysis of the ratio of maximum hemicraniectomy diameter to maximum anteroposterior diameter gave a mean difference of 0.04 (95% CI: 0.05-0.07; p=0.026). The addition of ZA resection to standard DC may prove valuable in terms of absolute brain volume gain. This technique is comparable to other maneuvers used to provide maximum brain expansion in the immediate post-operative period.