Lasers in dentistry

STATEMENT OF PROBLEM: Three-dimensional (3D) printing of cobalt chromium (Co-Cr) removable partial dentures (RPDs)by selective laser melting (SLM) has been claimed to be less challenging than by conventional casting and provides significant improvements. However, the adaptation and fit of the SLM framework and the optimum build orientation are still unclear. PURPOSE: The purpose of this in vitro and clinical study was to evaluate the effect of different build orientations on the adaptation of removable partial denture frameworks fabricated by SLM technology in vitro and to compare the adaptation of the SLM and conventional RPD frameworks clinically...

OBJECTIVE: To assess the effects of arginine, with or without sodium fluoride (NaF; 1,450 ppm), on saliva-derived microcosm biofilms and enamel demineralization. METHODS: Saliva-derived biofilms were grown on bovine enamel blocks in 0.2% sucrose-containing modified McBain medium, according to six experimental groups: control (McBain 0.2%); 2.5% arginine; 8% arginine; NaF; 2.5% arginine with NaF; and 8% arginine with NaF. After 5 days of growth, biofilm viability was assessed by colony-forming units counting, laser scanning confocal microscopy was used to determine biofilm vitality and extracellular polysaccharide (EPS) production, while biofilm metabolism was evaluated using the resazurin assay and lactic acid quantification...

OBJECTIVE: Photobiomodulation (PBM) therapy is recommended by multiple international societies for managing oral mucositis (OM). These recommendations are based on extensive evidence. However, the search for an optimal PBM protocol continues. This mapping review focuses on a novel aspect of PBM therapy which is the immediate effect on pain levels associated with oral ulcerative conditions. DATA SOURCES: This literature review systematically compiles and evaluates the evidence about OM, alongside other oral ulcerative conditions, as the protocols that achieved pain relief for these oral conditions may have potential applicability to OM management...

BACKGROUND/PURPOSE: Porcine collagen is widely used in regenerative therapies to generate membranes for bone augmentation. However, porcine or bovine gelatin or collagen is often not appropriate for patients with creed and religious beliefs or for allergic reasons. In this study, we evaluated the potential of fish gelatin to generate membranes. MATERIALS AND METHODS: Fish gelatin and hydroxyapatite (HAp) were used at three different ratios (2:0, 2:1, 2:1.5, and 2:2) to prepare gelatin-hydroxyapatite (G-HAp) membranes via freeze-drying and heat-crosslinking...

BACKGROUND/PURPOSE: Periodontitis is an inflammatory condition of the tooth-supporting structures triggered by the host's immune response towards the bacterial deposits around the teeth. It is well acknowledged that pro-inflammatory interleukin (IL)-6, IL-8, MCP-1 as well as the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, are the key modulators in the activation of this response. Erbium-doped yttrium-aluminium-garnet (Er:YAG) laser, a solid-state crystal laser have been commonly used in the treatment of periodontal diseases...

The formation of dental plaque is well-known for its role in causing various oral infections, such as tooth decay, inflammation of the dental pulp, gum disease, and infections of the oral mucosa like peri-implantitis and denture stomatitis. These infections primarily affect the local area of the mouth, but if not treated, they can potentially lead to life-threatening conditions. Traditional methods of mechanical and chemical antimicrobial treatment have limitations in fully eliminating microorganisms and preventing the formation of biofilms...

BACKGROUND: In cariology studies, mitis-salivarius-bacitracin (MSB) agar has been commonly considered as the selective medium for Streptococcusmutans growth. The present study was the part of a funded project (a noninferiority randomized controlled trial) which compared the efficacy of a plant extract-based mouth rinse with that of a fluoride mouth rinse on the S.mutans counts of the children. AIM: This study aimed to identify the frequency of detection of S.mutans and nonstreptococcal bacterial species from the dental plaque of caries active children using a combined technique of anaerobic culture and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry...

OBJECTIVES: In this study, we aimed to compare the effectiveness of Gluma and high-power 980-nm diode laser, alone or in combination, in the treatment of cervical dentin hypersensitivity. METHODS: A total of 20 patients (5 men and 15 women), aged 25 to 60 years, who met the inclusion criteria, were enrolled in this study. A total of 60 teeth were randomly divided into 4 groups: G1, 980 nm diode laser (in 2 sessions within a 1-week interval); G2, Gluma (in 2 sessions within a 1-week interval); G3, 980 nm diode laser plus Gluma; and G4: control...

STATEMENT OF PROBLEM: The surface topography of metal substrate can affect its bond to porcelain. A neodynium-doped yttrium aluminum garnet (Nd:YAG) laser has been introduced to modify the metal surface topography and improve porcelain bond strength. However, studies on the effect of laser etching on metal to porcelain bond strength are lacking. PURPOSE: The purpose of this in vitro study was to determine the effect of Nd:YAG laser etching on the surface roughness and wettability of and the porcelain bond strength to cobalt chromium (Co-Cr) substrate fabricated by milling and direct metal laser sintering (DMLS)...

BACKGROUND: The objective this study was to evaluate the influence of preventive remineralizing techniques on surface roughness and volume loss of dentin submitted to erosive and/or abrasive challenges. MATERIAL AND METHODS: One hundred and eighty specimens of bovine root dentin were made; half of each was isolated (without treatment - WT) and half was subjected to the following remineralizing techniques: fluoride varnish (FV); Regenerate Boosting Serum® (RBS); Er,Cr:YSGG laser (L); fluoride varnish+laser (FV+L); Regenerate Boosting Serum®+laser (RBS+L)...

BACKGROUND: To evaluate the effectiveness of Er:YAG and Nd:YAG laser on dentin hypersensitivity prevention, associated or not to acidulated phosphate fluoride (APF) after erosive challenge. MATERIAL AND METHODS: 104 specimens were obtained from bovine dentine and divided into groups (n=13): G1: Er:YAG; G2: Er:YAG followed by application of APF; G3: application of APF followed by Er:YAG, simultaneously; G4: Nd:YAG; G5: Nd:YAG followed by application of APF; G6: application of APF followed by Nd:YAG, simultaneously; G7:application of APF; G8: untreated...

Objective: This article aims to review the safety and efficacy of the Er:YAG laser in debonding dental accessories. Methods: This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Articles published between 2010 and 2022 on the removal of dental accessories using erbium laser were searched. The selected articles were then classified according to the accessories used: adhesives, brackets, restorations, or implant crowns. Enamel surface roughness, shear bond strength, adhesive remnant index, duration time (t), pulp chamber temperature (T), morphology (M), and other variables were then noted...

Treatment of oral vascular anomalies (OVA) has focused on minimally invasive techniques rather than radical surgery. We investigated the efficacy and safety of diode laser using the photocoagulation technique in the management of OVA. Forty-seven subjects with OVA were treated with forced dehydration with induced photocoagulation (FDIP) using diode laser (808 nm/4.5 W). This series consisted mostly of male (63.8%) and non-white (63.8%) patients with a mean age of 57.4 years. Varices (91.5%), venous malformations (6...

INTRODUCTION: The purpose of this study was to investigate the influence of undercut depths on abutment teeth regarding the retentive force of clasps fabricated through selective laser melting (SLM), and to compare them with conventional cast clasps. METHODS: Akers clasps made of cobalt chromium alloy were fabricated using the SLM method (SLM), and the retentive forces were compared with clasps made with the conventional cast method (Cast). Three undercut amounts (0...

PURPOSE: The composition and properties of resin-based composite materials could affect tooth wear and lead to clinical problems. Therefore, the study objective was to characterize human tooth wear behavior against a bulk-fill restorative (BF) compared to a conventional resin composite (RC) and a CAD/CAM resin nano ceramic (RN). METHODS: Square-shaped specimens of each material were prepared and sub-divided according to the number of testing cycles (n=8): 100,000, 250,000, and 500,000 cycles...

PURPOSE: The aim of this study was to compare and assess the stress distribution and failure possibility of endodontically treated central incisor protected with endocrowns with different heights, with various CAD-CAM blocks such as IPS e.max CAD, Katana Zirconia, and Zolid Fx Zirconia. MATERIALS AND METHODS: A root canal-treated central incisor (plastic model) restored with an endocrown was scanned with a laser scanner to prepare a control model with a CAD software and then transferred to an FEA software...

PURPOSE: To study the antimicrobial effect of different concentrations of new bioactive glass(BG) on common bacteria in apical periodontitis of deciduous teeth. METHODS: The diameter (mm) of the inhibitory rings formed after treatment of Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum with the new bioactive glass was detected and observed by paper diffusion method, and the minimal inhibitory concentration(MIC), minimal bactericidal concentration (MBC) and minimal biofilm eradication concentration (MBEC) of E...

The aim of this study is to investigate the repair bond strength of composite resin following three different surface treatments (bur-grinding, silanization, and Er,Cr:YSGG laser irradiation) using various universal adhesives. A total of 160 resin composite specimens, produced in cylindrical form (6 × 2 mm) with a nanohybrid composite resin within metal molds, were subjected to 5000 cycles of aging in a thermocycler. The aged samples were categorized into four groups based on surface treatments: control, bur, silane, and Er,Cr:YSGG laser...

OBJECTIVES: To develop and practically test high-precision femtosecond laser ablation models for dental hard tissue that are useful for detailed planning of automated laser dental restorative treatment. METHODS: Analytical models are proposed, derived, and demonstrated for practical calculation of ablation rates, ablation efficiency and ablated morphology of human dental enamel and dentin using femtosecond lasers. The models assume an effective optical attenuation coefficient for the irradiated material...

Accomplishment of an ideal root canal treatment is attributed to various essential factors such as proper instrumentation, chemomechanical preparation, obturation and post endodontic restoration. The main aim of this study is to test the null hypothesis that is the moisture condition of root dentin would not affect the bond strength and sealer penetration. This is an in vitro study conducted in Department of Conservative Dentistry and Endodontics, M A Rangoonwala Dental College, Pune, India over a period of two years (from 2021 to 2023)...