Knowledge about the influence of fillers in denture base resin is vague. This systematic review aimed to report the reinforcing effect of fillers on the mechanical properties of denture base resin by following PRISMA guidelines. Two electronic databases (Pubmed/Medline & Web of Science) were searched for articles using the keywords: fibers in denture base, fillers in denture base, and reinforcement of denture base. Laboratory studies complying with the inclusion criteria were reviewed according to the set protocol. The established focus question was: “Do reinforcing fillers positively influence the mechanical properties of polymethyl methacrylate (PMMA) heat polymerized denture base material?” A total of twenty-nine relevant papers qualified for final inclusion. Of these, 24 were determined to have a moderate risk of bias. Micron or nano-sized metal/metal oxides particles and glass fibers were the frequently used reinforcing agents. The trend of evaluating fractural strength (FS) was common. Most of the studies limited the use of reinforcing agents up to 5 wt.%. FS, fracture toughness (FT), and impact strength (IS) tend to increase if the fillers are chemically bonded and well-dispersed in denture base resin. Though fillers with a higher elastic modulus increase the hardness of the reinforced denture base resin, they compromise other mechanical properties. Well-dispersed lower filler loading PMMA denture base resin can enhance the FS, FT, and other related mechanical properties.

AimThe objective was to compare the marginal leakage (silver nitrate uptake) of nanohybrid resin-based composite (RBC) and two bulk-fill flowable RBCs with specific clinical protocols.MethodsFour experimental groups of RBC were investigated including conventional composite Filtek™ Supreme in 2 mm increment (FS2), Filtek™ Supreme in 4 mm increment (FS4), Filtek™ Supreme Flowable (BFF), and SureFil® SDR® flow (SDR). Class II box preparation (4 × 4 × 3 mm) in extracted intact human molars was carried out and restored using the experimental groups, all according to the manufacturers’ recommendations except FS4. Samples were aged by thermocycling (2,000 cycles). Microleakage was calculated by measuring dye penetration in sectioned teeth using a stereomicroscope. Level of significance was set at P < 0.05.ResultsBFF and FS2 exhibited the least dye penetration and microleakage measurement with no significant difference between the two groups, followed by SDR. FS4 showed the highest microleakage with significant difference in comparison with BFF and FS2. Gingival microleakage was found to be significantly higher than occlusal microleakage.ConclusionThe microleakage of the bulk-fill composites BFF and SDR are comparable with conventional composite FS2; however, it is more predictable to use FS2.

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Objectives To investigate the psychosocial impact of malocclusion and self-rated and clinician-rated orthodontic treatment need on young adult patients in the Western Province of Saudi Arabia. Materials and Methods Eighteen- to 30-year-old patients (n=355) attending a tertiary dental care facility were included. Three instruments were used for data collection: (1) Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ), (2) aesthetic component of the Index of Orthodontic Treatment Need (IOTN-AC), self-rated and clinician-rated, and (3) clinician-rated Dental Aesthetic Index (DAI). Data analysis included descriptive statistics, Kruskal–Wallis test, Mann–Whitney U-test, and multiple linear regression analysis. Results Females were significantly more impacted than males on all domains with the exception of the dental self-consciousness domain. For both the self-rated and clinician-rated IOTN and the DAI, it was found that the more severe the malocclusion, the higher the impact on all domains except for the dental self-confidence domain, which showed that patients with mild malocclusions were more affected than those with moderate and severe malocclusions. Significant associations were observed between independent variables (age, sex, self-rated IOTN, and DAI) and total PIDAQ score. Conclusions Perceived psychosocial impact of dental aesthetics is directly related to severity of malocclusion (self-rated and clinician-rated) for all domains of the PIDAQ accept the DSC, and females showed higher psychosocial impact than males. Clinicians should consider the impact of malocclusion and certain demographic characteristics on the psychosocial well-being of an individual when determining the orthodontic treatment need.