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Objective This study aimed to investigate the effect of relining prefabricated fiber-reinforced composite (FRC) posts using bulk-fill, flowable, discontinuous short fiber-reinforced composite (SFRC) on intracanal adaptation in weakened endodontically-treated premolar teeth. Materials and Methods Forty extracted human premolar teeth were selected and randomly allocated to five groups (n = 8) according to the canal preparation method and restorative technique after endodontic treatment: Group 1 (control): nonflared, closed apex root canals; group 2, 4: flared, open-apex root canals; group 3, 5: flared, closed apex root canals. Groups 1 to 3 were restored with standard RelyX fiber post size #1, while groups 4 and 5 were restored with customized RelyX fiber post size #1 and relined with bulk-fill flowable SFRC (everX Flow, GC, Tokyo, Japan). To evaluate intracanal adaptation, the empty root of each sample with the corresponding fiber post (standard or customized) inserted was measured twice using a micro-digital scale and the average value was calculated. The post was then removed, followed by the insertion of a light body polyvinyl siloxane (PVS) impression material into the canal, followed by reinsertion of the post and removal of excess material once the PVS was set. Finally, the sample weight was recorded, and the data were analyzed using one-way analysis of variance and the Bonferroni post hoc test (p-value = 0.05). Results A statistically significant difference (p Conclusion Anatomically-customized fiber posts with bulk-fill flowable SFRC provided better intracanal adaptation compared with standard fiber posts in teeth with compromised root canals.

Objective This study aimed to evaluate the flexural and compressive strength of kenaf-reinforced composite resin as well as analyze the length and diameter of kenaf fibers and their surface topography. Materials and Methods Kenaf fibers were alkaline treated and wetted with coupling agent. Kenaf-reinforced composite resin was fabricated manually. Specimens for kenaf-reinforced composite resin (Tetric N Flow [Ivoclar Vivadent, Liechtenstein] + 2% kenaf) and control group (Tetric N Flow [Ivoclar Vivadent, Liechtenstein]) were prepared using stainless steel molds with dimension of 25 mm × 2 mm × 2 mm and 6 mm × 4 mm for flexural and compressive strength tests, respectively, and tested using Instron Universal Testing Machine (Shimadzu, Japan). Raw kenaf fibers, treated kenaf fibers, and fractured sample from flexural strength test were analyzed using scanning electron microscopy (SEM) (FEI Quanta FEG 450, United States). Data were analyzed using independent sample t-test. Significant level was set at p < 0.05. Results Kenaf-reinforced composite resin has a lower flexural and compressive strength than the control group (p < 0.05). SEM analysis revealed the average fibers’ length to be 1.24 mm and diameter ranging from 6.56 to 12.9 μm. The fibers dispersed in composite as single strand or a bundle with a minimal gap between fibers and composite. Conclusion Flexural and compressive strengths of kenaf-reinforced composite resin were lower than the control group, despite some adaptation between kenaf fibers and composite noted. The fibers’ length and diameter were reasonable for the dispersion in the resin matrix; however, additional treatments of kenaf are required for a favorable result.

Objective: This study is aimed to investigate interfacial micro gaps between bases and hard setting calcium hydroxide liner. Materials and Methods: Twelve sound extracted human maxillary premolars were selected and immersed in 0.1% thymol solution. Samples were subjected to Class I cavity preparations with the width of 2.5 mm buccolingually, 3 mm mesiodistally, and 2 mm depth from the dentinoenamel junction (DEJ). The cavities were lined with hard setting calcium hydroxide lining (Dycal®), (Dentsply, USA) and then divided randomly into two groups. The cavities were restored with smart dentin replacement (SDR®), (Dentsply, Germany) and glass ionomer cement Ketac™ N100 (3M ESPE, USA) for Group 1 and 2, respectively, (n = 6 for each group) up to DEJ level. All samples were then packed with composite resin. Samples were cut longitudinally using a hard tissue cutter (Exact, Japan) and sanded with increasing grit sandpaper (#320, #500, #800, and #1200) for 30 s each and subjected for interfacial micro gaps analysis using scanning electron microscopy. Results: There was a significant difference of micro gap formation between two groups of base materials and hard setting calcium hydroxide (Dycal®) (P < 0.05). Conclusions: Lesser micro gap between Dycal® and SDR® compared to Dycal® and Ketac™ N100 suggested SDR® as a better base material to be used with Dycal® for deep caries management.

Introduction: Coronavirus disease 19 (COVID-19) is a highly contagious and virulent infection caused by severe acute respiratory syndrome coronavirus 2. The symptoms arise within 2 to 14 days after the infection. The specimens are collected from the upper respiratory tract through nasopharyngeal and oropharyngeal swab. This sampling requires close contact with COVID-19 patients and may directly cause transmission to health care professionals. Saliva specimens can be collected easily by asking patients to spit into a sterile container. Materials and Methods: In the current study, the selected patients (n = 20) were those who tested positive for COVID-19 and were admitted to the hospital. After getting approval from ethical committee of the hospital, both nasopharyngeal swab specimens and the salivary samples of each patient were collected and tested using standard procedure of real-time polymerase chain reaction. Results: The mean cycle threshold values obtained from both the sampling techniques were correlated. It was seen that there was no significant difference between them. The advantage of using saliva as a specimen is in the overall specimen collection procedure and its cost and time effectiveness. The diagnosis of COVID-19 through a rapid test procedure using salivary samples could be a boon to dentists. Conclusion: This would help in the detection of positive asymptomatic carriers of the virus among the patients who come to seek dental treatment and reduce the risk of infection in the dental office. The results of this study clearly show that the values obtained from the two sampling techniques are closely related, and hence saliva could definitely be considered as a diagnostic aid for COVID-19.

Svrha istraživanja: Namjera je bila usporediti prilagodbu kompozitnih intrakanalnih kolčića ojačanih vlaknima i lijevanih nadogradnji. Materijal i metode: Sedamnaest izvađenih ljudskih trajnih gornjih središnjih sjekutića endodontski je izliječeno prema standardnom protokolu. Sedamnaest kompozitnih intrakanalnih kolčića ojačanih vlaknima prilagođeno je prepariranim paralelnim korijenskim kanalima. Nisko viskozni vinil-polisiloksan (EXAMIX NDS, Japan) za otiske unesen je u korijenski kanal nakon kolčića. Digitalnom vagom izmjerena je masa preostalog materijala koji je ispunjavao prazninu između kolčića i unutarnje stijenke kanala. Prilagodba je određena na temelju razlika u masi prije unošenja otisnog materijala i nakon toga postupka. To isto ponovljeno je sa 17 lijevanih nadogradnji na istim zubima kao uzorcima. Rezultati: Srednja razlika u masi materijala unutar skupine bila je statistički značajna (p vrijednost < 0,001) s vrijednošću od 6,1 mg (± 2,7mg) za lijevane metalne nadogradnje i 6,4 mg (± 2,7mg) za kolčiće ojačane kompozitnim vlaknima. No srednja razlika nije bila statistički značajno različita kada su se uspoređivala oba materijala (p vrijednost > 0,05). Zaključak: I lijevana nadogradnja i vlaknima ojačani kompozitni intrakanalni kolčić slično su se prilagodili stijenkama korijenskog kanala., Background: The purpose of this study was to compare the adaptation of fiber reinforced composite post system and cast post-and-core. Methods: 17 extracted human permanent maxillary central incisors were endodontically treated following the standard protocol. 17 fiber reinforced composite post had been fabricated and adapted to the prepared parallel root canals. A light body poly vinyl siloxane (EXAMIX NDS, Japan) impression material was inserted into the root canals followed by the post. A digital scale was used to measure the weight of the remaining material that filled the gap between the post and the canal wall. The adaptation was indicated by the weight difference before and after impression material insertion. The same procedures were repeated with 17 cast post-and-core in the same teeth specimens. Result: The mean difference for the weight of the material within the group was statistically significant (P-value 0.05). Conclusions: Both cast post-and-core and fiber reinforced composite post systems showed similar adaptation to the canal.

Objectives: The aim of this study was to identify the requirements in restorative dentistry that undergraduate dental students have to fulfill in order to sit for final examinations in dental schools in Malaysia and to compare those requirement with the competencies stipulated by the Malaysian Qualification Agency (MQA). Materials and Methods: Questionnaire from a study done previously was modified and used in this study. All questionnaires were sent by post with a reply envelope. Eight dental schools had responded (72%) to the survey and the results showed that although dental schools may differ in the number of numerical requirements, their assessments were quite similar. One school does not practice numerical requirements at all. Results: In term of requirement for full crown, majority of the schools (88%) agreed that porcelain bonded to metal crown should be included in the numerical requirement. In contrast, majority of the schools (88%) did not include inlay/onlay in their numerical requirements. For plastic restorations like composite resin, amalgam and glass ionomer, majority of the schools (88%) used numerical requirements. Majority of the schools also agreed on numerical requirements for conventional bridge (88%) and incisor to molar endodontics (88%), but not for resin bonded bridge (75%). Conclusion: This study shows that there is a disparity among institutions in Malaysia in terms of finals requirement in restorative dentistry. Ideally, all requirements should be similar among institutions and should closely follow the guidelines provided by the MQA. DOI: http://dx.doi.org/10.3329/bjms.v12i1.13352 Bangladesh Journal of Medical Science Vol. 12 No. 01 January’13 pp.55-62