The impact of Streptococcus mutans biofilms on the color stability and topographical features of three lithium disilicate ceramics.

Purpose: Secondary caries around ceramic restorations is the most common reason for the replacement of fixed dental prostheses (FDPs). Therefore, it is important to examine the susceptibility of different ceramic materials to biofilm formation. This study aimed to evaluate biofilm development and associated roughness and color alterations in three lithium disilicate ceramics: Emax CAD (EC), Emax Press (EP), and LiSi Press (LP).

Impact of combining dental composite brushes with modeling resins on the color stability and topographic features of composites.

This study explores the effect of using dental brushes with or without metacrylate-based modeling resins on long-term color stability and surface topographies of resin-based composites. This study examined the effects of two variables: (1) the type of brush used (Art brush, Micro-brush, or Mylar strip) and (2) the application of a modeling resin (applied or not applied). The specimens were artificially aged through 10,000 cycles of thermocycling and subsequently immersed in coffee for 30 days.

Evaluation of the information provided in the instruction manuals of dental light-curing units.

Objective: This study evaluated the completeness and accuracy of information in LCU instruction manuals from 40 manufacturers.

Materials And Methods: Instruction manuals from 40 LCUs (20 from leading manufacturers and 20 budget units) were reviewed. Twenty-eight parameters across five categories were assessed using a binary scale (0=incorrect/missing, 1=correct).

Impact of storage conditions on the fracture reliability and physical properties of a dental resin-based composite.

This study investigated the impact of 'storage condition' and 'period of storage' on selected physico-mechanical properties and fracture reliability of a resin-based composite (RBC). Specimens, prepared from a nanofilled RBC (Filtek Z350 XT; 3M ESPE), underwent tests for degree of conversion (DC), flexural strength (σ), flexural modulus (E), and hardness. The specimens were initially grouped into dry storage at 37°C or wet storage in distilled water at 37°C.

Assessment of internal porosities for different placement techniques of bulk-fill resin-based composites: a micro-computed tomography study.

Objectives: The aim was to compare the porosity of different bulk-fill resin-based composites (RBCs) placement techniques to the conventional incremental technique using microcomputed tomography (μ-CT).

Material And Methods: Occlusal cavities were prepared on extracted human molars, divided into five groups based on the placement technique (n = 10/group). Techniques examined were Monoblock-two-step (SureFil SDR flow + Ceram.

Shedding light on the problem: Proficiency and maintenance practices of light-curing units among dental assistants.

Background: Proper light curing is crucial for the success of restorative dentistry and to bond brackets to teeth, yet the responsibility is often delegated to dental assistants (DAs). This study assessed the proficiency and maintenance protocols of DAs when using light-curing units (LCUs) in Saudi Arabia.

Methods: Self-administered questionnaires were distributed to practicing DAs.

Inorganic Compounds as Remineralizing Fillers in Dental Restorative Materials: Narrative Review.

Secondary caries is one of the leading causes of resin-based dental restoration failure. It is initiated at the interface of an existing restoration and the restored tooth surface. It is mainly caused by an imbalance between two processes of mineral loss (demineralization) and mineral gain (remineralization).

Skill Retention of Light-Curing Technique Using Only Verbal Instructions versus Using an Instructional Video: A 2-Year Follow-Up Study of Dental Students.

Purpose: To evaluate the retention of light-curing skills among dental students after two years of clinical experience and determine if there are any differences in the skills retention between students who received verbal instructions or those who had received an instructional video. The students' satisfaction with past learning, self-confidence, and general knowledge about light-curing were also evaluated.

Methods: This study is a 2-year evaluation of previous work.

Attitude, Practice, and Knowledge Regarding Fluoridated Toothpaste, Brushing, and Rinse Usage Among Residents of Jeddah City in Saudi Arabia.

Purpose: To evaluate and compare the attitude, practice, and knowledge of individuals who use fluoridated and non-fluoridated toothpaste in Jeddah city, Saudi Arabia.

Methods: A digital questionnaire composed of 43 questions were formulated. The questionnaire was divided into five sections: eligibility questions, demographic data, attitude, practice, and knowledge.

Effects of nanohybrid flowable resin-based composites on fibroblast viability using different light-curing units.

Purpose: To investigate the in vitro cytotoxic effects of Bis-GMA-containing and Bis-GMA-free flowable resin-based composites (RBCs) on primary human gingival fibroblast cells (hGFc) using direct and indirect curing methods and three different light-curing units (LCUs).

Materials And Methods: Cells were isolated and cultured in vitro in 24-well plates. The plates were divided into treatment (cells with RBC), control (cells only), and blank (media only) groups.

Effects of aging and light-curing unit type on the volume and internal porosity of bulk-fill resin composite restoration.

This study explores the effects of aging (thermal cycling and cyclic loading-TC/CL) and different light-curing unit (LCU) types on the volume characteristics and internal porosity of a bulk-fill resin-based composite restoration. Occlusal cavities (4 × 4 × 3 mm) were prepared on extracted human molars (n = 5). Tetric N-Bond Universal was applied, and the cavities were restored using Tetric-N-Ceram Bulk Fill.

Dental Students' Didactic and Psychomotor Skills Performance in Dental Anatomy and Preclinical Operative Dentistry Courses in a Saudi Governmental School.

Background: Knowledge and psychomotor skills are essential in dental education. The aims were to (1) investigate the correlation between dental students' didactic and psychomotor skills performance in the dental anatomy and preclinical operative dentistry courses and (2) explore the impact of gender on students' performance in both courses.

Materials And Methods: A retrospective cohort study was performed on dental students' (164 students; 72 males and 92 females) dental anatomy and preclinical operative courses scores of the same class over 2 years (2018-2020).

Impact of grit, resilience, and stress levels on burnout and well-being of dental students.

Objective: Dentistry is demanding and requires a high level of diligence and resilience, resulting in high stress that may impact students' burnout and well-being. The aims were to: (1) investigate the levels of grit, resilience, stress, burnout, and well-being among students at King Abdulaziz University-Faculty of Dentistry; (2) explore age, gender, dentistry as the first career choice, academic level, grit, resilience, and stress as predictors for burnout and well-being among dental students; (3) investigate the correlations among grit, resilience, stress, burnout, and well-being among dental students.

Methods: An electronic questionnaire was distributed, comprised of demographic information and five validated scales: (1) grit (grit-8-item); (2) resilience (The Connor-Davidson resilience scale (CD-RISC)); (3) stress (perceived stress scale); (4) burnout (Oldenburg Burnout Inventory); (5) well-being (World Health Organization-5).

Effectiveness of Using an Instructional Video in Teaching Light-Curing Technique.

Purpose: To investigate dental students' ability to deliver satisfactory amounts of irradiance and radiant exposure to simulated cavities by teaching the light-curing technique using instructional video compared to verbal instructions.

Methods: Students attended the didactic light-curing lecture explaining the light-curing technique. Participants were divided into two groups (n=60).

Effect of light-curing distance and curing time on composite microflexural strength.

This study investigated the influence of curing distance on µ-flexural strength (µ-FS) of a nano-hybrid composite, cured using the manufacturer-recommended curing time (MCT), compared to a consistent radiant exposure (CRE) using three different light-curing units (LCUs). Beams (6×2×1 mm) were cured using the MCT or CRE with a quartz-tungsten-halogen (QTH); a single-emission-peak light-emitting-diode (SLED), or a multiple-emission-peak light-emitting-diode (MLED) LCU. Specimens were cured at 0-, 2- or 8-mm distances (n=10) and the bottom irradiance and CRE were measured using a Managing Accurate Resin Curing-Resin Calibrator spectrometer.

Polymerization pattern characterization within a resin-based composite cured using different curing units at two distances.

Objectives: To investigate the relationship of the irradiance-beam-profile areas from six different light-curing units (LCUs) with the degree of conversion (DC), microhardness (KH), and cross-link density (CLD) throughout a resin-based composite (RBC) cured at two clinically relevant distances, and to explore the correlations among them.

Materials And Methods: A mapping approach was used to measure DC using micro-Raman spectroscopy, KH using a Knoop indentor on a hardness tester, and %KH reduction after ethanol exposure, as an indicator for CLD within a nano-hybrid RBC increment (n = 3) at various depths. These sample composites were cured from two distances while maintaining the radiant exposure, using six different light-curing units: one quartz-tungsten-halogen; two single and three multiple-emission-peak light-emitting-diode units.

Variation in composite degree of conversion and microflexural strength for different curing lights and surface locations.

Background: Lack of irradiance-beam profile uniformity across the emission area of light-curing units (LCUs) may result in suboptimal properties of composite restorations. The authors' objective for this study was to assess the variation in local cure of 1 composite at 3 different LCU emission area locations cured with 3 different LCUs by means of testing the degree of conversion (DC) and microflexural strength.

Methods: The authors fabricated dual-photoinitiator composite specimens (n = 5), which were cured using either a quartz-tungsten-halogen, a multiple-emission peak, or a single-emission peak light-emitting diode LCU.

Effects of air-abrasion pressure on the resin bond strength to zirconia: a combined cyclic loading and thermocycling aging study.

Objectives: To determine the combined effect of fatigue cyclic loading and thermocycling (CLTC) on the shear bond strength (SBS) of a resin cement to zirconia surfaces that were previously air-abraded with aluminum oxide (AlO) particles at different pressures.

Materials And Methods: Seventy-two cuboid zirconia specimens were prepared and randomly assigned to 3 groups according to the air-abrasion pressures (1, 2, and 2.8 bar), and each group was further divided into 2 groups depending on aging parameters ( = 12).

Degree of conversion and cross-link density within a resin-matrix composite.

The aims of this study were to profile light radiated from two light-curing units (LCUs) and evaluate profile relationship to polymerization patterns within a resin-matrix composite (RMC). Beam profiles of one multiple emission peak light-emitting-diode and one quartz-tungsten-halogen curing-unit were measured using a beam profiler/spectrometer system. A camera-based profiler and an integrating sphere/spectrometer assembly were used to evaluate each LCU beam.

Evaluation of selected properties of a new root repair cement containing surface pre-reacted glass ionomer fillers.

Objective: This study evaluated selected properties of a prototype root repair cement containing surface pre-reacted glass ionomer fillers (S-PRG) in comparison to mineral trioxide aggregate (MTA) and intermediate restorative material (IRM).

Materials And Methods: The antibacterial effect of S-PRG, MTA, and IRM cements was tested against Porphyromonas gingivalis and Enterococcus faecalis after 1 and 3 days of aging of the cements. The set cements were immersed in distilled water for 4 h to 28 days, and ion-releasing ability was evaluated.

Synthesis and characterization of novel halloysite-incorporated adhesive resins.

Objective: To investigate the effects of Halloysite® aluminosilicate clay nanotubes (HNTs) addition on selected physical, mechanical, and biological properties of experimental adhesive resins.

Methods: Experimental dentin adhesive resins were prepared by mixing Bis-GMA, TEGDMA, HEMA (50/25/25wt.%), and photo-initiators.