^{August 2018 Abstracts}

 

 

 

 

 

 

 

A 6-month clinical evaluation of a high frequency sonic toothbrush in comparison with an oscillating-rotating power toothbrush and a traditional sonic toothbrush in reducing gingivitis and plaque

 

Jing Lv, mm,  Bing Guo, mm  &  Junqi Ling, dds

 

Abstract: Purpose: To compare the 6-month clinical efficacy of a novel high frequency sonic power toothbrush (A) with an oscillating-rotating (O-R) power toothbrush (B) and a traditional sonic toothbrush (C) in reducing plaque and gingivitis. Methods: This was a single-center, randomized, examiner-blind, parallel group design consisting of two two-treatment sub-trials. Gingivitis was assessed using the Modified Gingival Index (MGI) and Gingival Bleeding Index (GBI). Plaque was assessed using the Rustogi Modified Navy Plaque Index (RMNPI) at Baseline, Month 3, and Month 6. Statistical analysis between A versus B and A versus C were evaluated. Data were analyzed using an ANCOVA with the baseline score as the covariate. Results: In total, 120 subjects (40 per group) were randomized to treatments and 119 subjects completed the study. All power toothbrushes provided statistically significant reductions in gingivitis and plaque relative to Baseline (P< 0.001). Reductions in MGI and GBI scores were not statistically significantly different between A and B at Months 3 and 6. While A had statistically significant 20.1% and 29.0% greater reductions in total RMNPI and interproximal RMNPI respectively, compared to B at Month 6 (P< 0.05). Reductions in gingivitis and plaque indices were not statistically significantly different between A (41,000 oscillations/minute) and C (31,000 oscillations/minute) at Month 3. Compared to C, A demonstrated 14.0% and 14.5% greater reductions in MGI and GBI respectively, and 26.0% greater reduction in interproximal RMNPI versus baseline at Month 6 (P< 0.05). No adverse events were reported for the power toothbrushes. (Am J Dent 2018;31:171-176).

 

 

Mail: Junqi Ling, Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology and Institute of Stomatological Research, Sun Yat-sen University. 56 Lingyuanxi Rd., Guangzhou 510055, China. E-mail: lingjq@mail.sysu.edu.cn

 

 

 

 

 

Effect of desensitizing toothpastes on dentin erosive wear and tubule occlusion. An in situ study

 

Raquel Marianna Lopes, dds, msc, Tais Scaramucci, dds, phd  &  Ana Cecilia Corrêa Aranha, dds, msc, phd

 

Abstract: Purpose: To evaluate the effect of desensitizing dentifrices on dentin wear and tubule occlusion using a three-phase, single blind, crossover in situ trial. Methods: The dentifrices containing Arginine and calcium carbonate (1,450 ppmF) and Novamin, (~1,426 ppmF) were tested in two conditions: A: abrasion and B: erosion/abrasion. A dentifrice without desensitizing agents was used as control (1,450 ppmF). In each study phase, 10 volunteers used intra-oral appliances containing dentin specimens (pre-treated with EDTA, to simulate hypersensitive dentin), which were either submitted to erosion with a cola-like drink (pH 2.6), 4×/day (2 minutes), followed by toothbrushing, using electric toothbrushes, with standard pressure (2×/day, 5 seconds), or toothbrushing only. Dentin surface loss (SL, in µm) was determined with optical profilometry at the 3rd and 5th days of cycling. Dentin surface was analyzed with environmental scanning electron microscopy (ESEM), post EDTA and post cycling, and the dentin tubules were counted using Image J software. Data were statistically analyzed (α= 0.05). Results: For condition A and B, there were no significant differences in SL among toothpastes in both experimental times. There were also no significant differences between times within groups. For ESEM, in A, Toothpaste with Novamin was the only dentifrice that showed significantly less opened tubules post cycling than post EDTA. In B, Toothpaste with Novamin and control toothpaste presented less opened tubules post cycling. In conclusion, toothbrushing with the tested dentifrices promoted similar levels of dentin loss; however, for tubule occlusion, the toothpaste with Novamin was the only toothpaste effective for both conditions, abrasion and erosion/abrasion. (Am J Dent 2018;31:177-183).

 

 

 

 

 

 

 

 

Mail: Prof. Dr. Ana Cecilia Corrêa Aranha, Department of Restorative Dentistry, School of Dentistry, University of São Paulo, Prof. Lineu Prestes, 2227 Cidade Universitária, São Paulo, 05508-000, SP, Brazil. E-mail: acca@usp.br

 

 

 

Subgingival uptake and retention of stannous fluoride from dentifrice: Gingival crevicular fluid concentrations in sulci post-brushing

 

Malgorzata A. Klukowska, phd, dds, Niranjan Ramji, phd, Chelsea Combs, ms, Jeffery L. Milleman, dds, mpa, Kimberly R. Milleman, rdh, bsed, ms, David L. Ramsey, ms, Usa Rattanaudompol, ms, Christina Haven, bs, Denise McClenathan, phd  &  Donald J. White, phd

 

Abstract: Purpose: To examine the delivery of stannous fluoride to subgingival sulci following toothpaste use in a clinical population. Methods: This was a controlled, single-site study. 23 subjects with at least 20 dental pockets, 2-4 mm with bleeding, who had not used a stannous fluoride dentifrice in the last 3 months were enrolled. After a 2-week washout period, 20 subjects returned for a baseline visit. They were instructed to refrain from brushing the night before the baseline visit. GCF samples were taken from up to 10 sites identified as sampling sites. Subjects were then given a 0.454% stannous fluoride dentifrice and soft manual toothbrush and asked to brush for 1 minute. 30 minutes after brushing, GCF was re-sampled. Subjects continued using the stannous fluoride dentifrice and soft manual toothbrush at home, twice daily for 2 weeks, in place of their usual hygiene products. At Days 1 and 14, subjects returned to the site, and 12 hours post-brushing GCF samples were taken. The samples were analyzed by ICP-MS (inductively coupled plasma mass spectrometry). A Wilcoxon signed-rank test was performed to determine the difference between post-baseline visits and baseline. Statistical tests were 2-sided using a 5% significance level. Results: 20 subjects completed the trial. Significant levels of tin, a marker for stannous fluoride, were detected 30 minutes after brushing at sampling sites of 2-4 mm. The median tin level in gingival crevicular fluid (GCF) was 24.59 ng/µl, which was highly significant versus baseline (P< 0.0001). Tin levels sampled in GCF 12 hours after brushing on Days 1 and 14 were highly significant versus Baseline (P< 0.0001), showing an increasing trend with continued use. (Am J Dent 2018;31:184-188).

 

 

Mail: Dr. Donald J. White, 5567 Lakeside Drive, Fairfield, OH  45014.  E-mail: lamadental@outlook.com

 

 

Randomized clinical trial to determine if changes in dentin tubule occlusion visualized by SEM of replica impressions correlate with pain scores

 

Joon Seong, bds, phd,  Maria Davies, bsc, phd,  Emma L. Macdonald, bsc, phd,  Nicholas C.A. Claydon, bds, mscd, phd &  Nicola X. West, bds, phd

 

Abstract: Purpose: To quantify dentin tubule occlusion and correlate this with pain reduction in vivo. Methods: This was a single-center, randomized two treatment, examiner-blind, parallel study. 20 participants with confirmed dentin hypersensitivity (DH) were evaluated by Schiff Air Blast, VAS Air Blast and replica impression of the tooth surface to visualize tubule occlusion at baseline and following 4-week twice daily use of either an occluding toothpaste (8% strontium acetate, 1,040 ppm fluoride) or a non-occluding toothpaste (1,450 ppm fluoride). Results: Both treatments increased tubule occlusion significantly from baseline to 4 weeks (P= 0.01) with significant decreases in pain score only seen with the occluding toothpaste (Schiff, P= 0.01; VAS, P= 0.01). Schiff pain score after 4 weeks was markedly reduced following treatment with the occluding toothpaste as compared to the non-occluding toothpaste, (P= 0.05) with no significant differences between the pastes for occlusion score or patient reported VAS, although the scores favored the occluding toothpaste. (Am J Dent 2018;31:189-194).

 

 

Mail: Prof. Nicola X. West, Periodontology, Clinical Trials Unit, Bristol Dental School, Lower Maudlin Street, Bristol, BS1 2LY, United Kingdom. E-mail: n.x.west@bristol.ac.uk

 

 

 

Efficacy of ibuprofen and codeine + paracetamol to reduce immediate bleaching sensitivity caused by in-office tooth bleaching: A randomized, controlled, double-blind clinical trial

 

Samila Neres de Oliveira, dds,  Isauremi Vieira de Assunção, dds, msc, phd &  Boniek Castillo Dutra Borges, dds, msc, phd

 

Abstract: Purpose: To evaluate (1) the efficacy of Ibuprofen and codeine + paracetamol to control immediate bleaching sensitivity caused by in-office tooth bleaching performed with 35% hydrogen peroxide, and (2) tooth shade change caused by 35% hydrogen peroxide. Methods: In this randomized, controlled and double blind clinical trial, 60 volunteers were divided into three treatment groups: 400 mg placebo (PL)(n=20), 400 mg ibuprofen (IB)(n=20), or 30 mg codeine + 500 mg paracetamol (CP)(n=20). The volunteers were submitted to two bleaching sessions with 35% hydrogen peroxide in 2 applications of 20 minutes each. In both sessions, the medication was given to the volunteers 1 hour before the bleaching procedure. The sensitivity values were obtained with the analogic visual pain scale. Tooth shade was assessed before and after bleaching. Statistical analysis was done through the one-way ANOVA and Tukey post-hoc tests. Results: For bleaching sensitivity, there were statistically significant differences among the medications (P< 0.01). The lowest sensitivity means were found in the CP group (PL:4.7 = IB:4.8 > CP:1.0). In regards to tooth shade, participant’s teeth were statistically significantly lighter after bleaching than before bleaching (P< 0.01), with no statistically significant difference between the medications (P< 0.05). (Am J Dent 2018;31:195-198).

 

 

Mail: Dr. Boniek Castillo Dutra Borges,  Av. Senador Salgado Filho 1787, Lagoa Nova, Natal,  RN,  59151-250  Brazil. E-mail: boniek.castillo@gmail.com

 

 

Surface treatments to improve the repair of acrylic and bis-acryl provisional materials

 

Thais Marques Simek Vega Gonçalves, dds, phd, Karla Nunes Teixeira, dds, phd, Julia Meller Dias de Oliveira, dds, Lorena Tavares Gama, dds, Sergio Bortolini, ds, phd  &  Analucia Gebler Philippi, dds, phd

 

Abstract: Purpose: To evaluate the in vitro effects of the Composite Primer and different surface treatments on the shear bond strength (SBS) of acrylic and bis-acryl repairs with resin composite (RC). Methods: Acrylic (Alike) and bis-acryl (Protemp 4) blocks were prepared. Surface roughness was standardized (0.16 µm) and grit blasting was applied to half of the samples. Blocks were divided randomly into groups according to surface treatment [methyl methacrylate monomer (MMA) for 180 seconds or bonding agents (Composite Primer and Scotchbond Multi Purpose), applied alone or following MMA]. Two consistencies of RC [regular (Filtek Z350XT and Solare composite) or flowable (Filtek Z350XT flowable and G-aenial flowable composite)] were used to test bond repair. Cylinders (2 mm diameter) of each RC (n= 10/group) were attached to the block surface, and SBS was measured using a universal testing machine at 0.5 mm/minute. Failure (adhesive, cohesive or mixed) was assessed under ×3.5 magnification. SBS data were analyzed using factorial ANOVA, followed by Tukey post-hoc, and Weibull moduli estimation (α = 0.05). Results: The highest SBS, Weibull modulus (m) and scale parameter (σ0) were found in combined use of MMA and bonding agents (P< 0.001), regardless of the substrate, RC consistency or brand. The use of the Composite Primer and flowable RC also increased SBS (P< 0.001). Significant interaction between surface treatment and RC consistency was observed for the PMMA substrate (P< 0.001). Sandblasting did not influence SBS (P> 0.05). Adhesive failure was most prevalent (93.5%) and SBS values were significantly higher in mixed fractures (19.2 ± 3.8 MPa) compared to the adhesive ones (9.7 ± 6.0 MPa) (P< 0.001). No cohesive fracture was observed. (Am J Dent 2018;31:199-204).

 

 

 

 

 

Mail: Dr. Thais Marques Simek Vega Gonçalves, Department of Dentistry, Federal University of Santa Catarina, University Campus, R. Eng. Agronômico Andrei Cristian Ferreira, s/n Mailbox 476, Trindade, 88040900, Florianópolis, SC, Brazil. E-mail: thaisgonc@gmail.com

 

 

 

Effect of thermal cycling on fracture toughness of CAD/CAM materials

 

Thiago Soares Porto, dds, msc, phd,  Renato Cassio Roperto, dds, msc, phd,  Anna Akkus, msc, phd, Ozan Akkus, msc, phd,  Sorin Teich, dmd, mba,  Fady F. Faddoul, dds, msd, Sizenando de Toledo Porto-Neto, dds, msc, phd  &  Edson Alves de Campos, dds, msc, phd

 

Abstract: Purpose: To compare the fracture toughness of four different CAD/CAM materials, (VM) Vitablocs Mark II, (IP) IPS e.max CAD, (LU) LAVA Ultimate, and (VE) Vita Enamic under long thermocycling conditions. Methods: Each type of ceramic block was sectioned into beams (n=9) with dimensions of 14×3×2.5 mm (L × W × H). All four ceramics were submitted to different conditions: the desiccator or distilled water, each for 7 days. The third and fourth conditions involved the specimens being submitted to 60,000 and 120,000 thermocycles in water respectively. The dwelling time was 52 seconds at 5° and 55°C. A three-point bend test with a universal loading machine on notched samples was per-formed. Furthermore, a fractographic analyses was made by scanning electron microscopy (SEM) to determine if any of these conditions influenced the type of fracture. Data were analyzed by two-way ANOVA (α= 0.05). Results: A significant difference in fracture toughness (P< 0.05) was found among the groups; IP (4.20±1.23) had the highest value followed by VE (2.02±0.39), which did not have a statistically significant difference from LU (1.96±0.42). The lower value and statistical difference for VM was 1.52±0.35. The ceramics performed better after they were hydrated, while the polymer-based materials had the fracture toughness means decreased after the thermocycles. (Am J Dent 2018;31:205-210).

 

 

Mail: Dr Thiago S. Porto, Department of Comprehensive Care, CWRU School of Dental Medicine, 2124 Cornell Rd, Cleveland, OH 44106, USA.  E-mail: txp209@case.edu

 

 

 

Effect of different mouthwashes on discoloration of plaque-free tooth surfaces

 

Mustafa Hayati Atala, dds, phd,  Gülbahar Ustaoğlu, dds, dclindent,  Nagehan Atala, dds &  Elif Yeğin, dds, dclindent

 

Abstract: Purpose: To evaluate the tooth discoloration effect of the daily use protocol of six different mouthrinses. Methods: 70 extracted caries-free central incisors were divided into seven groups (n=10/per group): Group 1: Curasept Anti Discoloration System; Group 2: CB12; Group 3: Listerine Zero; Group 4: Listerine Cool Mint; Group 5: Colgate Plax; Group 6: Kloroben. The teeth were exposed to the mouthrinse for 2 minutes daily for 3 weeks. Color measurement was performed four times: at the beginning of the study, and after 1, 2 and 3 weeks, with a digital spectrophotometer (Vita Easyshade Advanced). Color changes (∆E) were calculated and ANOVA and post hoc Tukey’s test were used for statistical analysis. Results: Although there was no statistically significant difference between the Colgate Plax and control groups, both groups had a significant difference from the other groups within all ∆E1, ΔE2 and ∆E3 values. (Am J Dent 2018;31:211-214).

 

 

 

 

 

Mail: Dr. Elif Yeğin, Department of Prosthodontics, Faculty of Dentistry, Biruni University, Zeytinburnu-Istanbul, Turkey. E-mail: dtelifyegin@gmail.com

 

 

 

Clinical effects of stannous fluoride dentifrice in reducing plaque microbial virulence III: Lipopolysaccharide and TLR2 reporter cell gene activation

 

Sancai Xie, phd, John Christian Haught, phd, Cheryl S. Tansky, ms, Malgorzata Klukowska, dds, phd, Ping Hu, phd, David L. Ramsey, ms, Ben Circello, phd, Tom G. Huggins, phd  &  Donald J. White, phd

 

Abstract: Purpose: This study expanded the analysis of subgingival dental plaques from previous research to include the evaluation of cohort, site and treatment effects on chemically measured endotoxin and activation of Toll-like receptor (TLR) based gene expression in two additional reporter cell lines: a TLR2 specific cell line and a THP-1 (multi TLR reporter) cell line. Methods: Participants from high and low bleeding cohorts were sampled at baseline for both supra and subgingival dental plaque at both healthy as well as clinically diseased sites and then provided with intervention hygiene products including a stabilized SnF₂ dentifrice and a new soft bristle manual toothbrush. Following 2 and 4 weeks of assigned dentifrice use, participants returned for a re-evaluation of gingival inflammation and bleeding and repeat samplings of dental plaque. Subgingival sampled plaques were chemically analyzed for endotoxin concentration using a Thermo Scientific Pierce LAL chromogenic endotoxin quantitation kit. Samples were also used for inoculation of two reporter cell assays (an HEK293 TLR2 reporter cell line and a THP-1 monocyte cell line). Reporter cell activation was analyzed via luminescence changes of secreted embryonic alkaline phosphatase. Results: The endotoxin content of subgingival plaque could be measured directly with dye assays and plaque isolates activated gene expression in both TLR reporter cell lines. Higher disease cohorts and sites with gingival inflammation generally showed more endotoxins and higher levels of plaque virulence as compared to low disease cohorts or plaque sampled from clinically healthy sites. SnF₂ dentifrice treatment was associated with broad scale reductions in endotoxin content and virulence potentiation properties of dental plaque samples collected subgingivally from patients. (Am J Dent 2018;31:215-224).

 

 

 

 

 

Mail: Dr. Donald J. White, 5567 Lakeside Drive, Fairfield, OH 45014, USA. E-mail: lamadental@outlook.com