Clinical assessment of a manual toothbrush with CrissCross and tapered bristle technology on gingivitis and plaque reduction

 

ZHIPENG XU, MDS,  XIN CHENG, BE,  ERINN CONDE, BS,  YUANSHU ZOU, PHD,  JULIE GRENDER, PHD &  RENZO ALBERTO CCAHUANA-VASQUEZ, DDS, PHD

 

ABSTRACT: Purpose: The primary aim of this study was to evaluate the gingivitis-reduction efficacy of an experimental manual toothbrush with CrissCross and tapered bristle technology in comparison with a marketed control manual toothbrush with traditional design and non-tapered bristles. In addition, the study compared the two toothbrushes for plaque-reduction efficacy. Methods: This was a randomized, controlled, parallel group, examinerblind, single-center, 4-week clinical trial with adult subjects in good general health. All subjects had presence of gingivitis (at least 10 bleeding sites). The subjects were randomly assigned to one of two treatment groups: a manual toothbrush having CrissCross and tapered bristle technology (tapered group: Oral-B CrossAction Ultrathin manual toothbrush); or a traditional flat-trim design and regular non-tapered bristles (control group: Oral-B Indicator Soft 35 manual toothbrush). Subjects were instructed to brush twice-daily for 4 weeks with their assigned brush and a standard sodium fluoride dentifrice. At baseline, Week 2, and Week 4, gingivitis was assessed using the Mazza Modification of the Gingival Bleeding Index (Mazza GI) and pre-brushing whole-mouth plaque was measured using the Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI). Results: 100 subjects (50 per group) were randomized to treatment and assessed at baseline, and 97 subjects (48 in the tapered group and 49 in the control group) completed the study. At both Weeks 2 and 4, both groups showed a significant (P< 0.005) reduction versus baseline in Mazza GI and number of bleeding sites, and the tapered group showed a significantly (P< 0.001) greater reduction from baseline for both these assessments compared to the control group. By Week 4 the tapered group showed a reduction from baseline of 17.9% in Mazza GI and 38.5% in the number of bleeding sites; the corresponding figures for the control group were 7.5% and 12.6%, respectively. Both groups showed a significant (P< 0.001) reduction versus baseline in TMQHPI by Week 4, with no significant (P=0.06) between-group difference. (Am J Dent 2019;32:107-112).

 

 

Mail: Dr. Zhipeng Xu, Shaanxi Provincial People’s Hospital No. 256 Youyi West Road, 710068 Xi'an, Shaanxi, China. E-mail: sxkq88@163.com

 

 

Surface treatment effects on bond strength of CAD/CAM fabricated posts to root canal dentin

 

Serra Oguz Ahmet, dds, phd, Ferhan Egilmez, dds, phd, Gulfem Ergun, dds, phd  &  Isil Cekic-Nagas, dds, phd

 

Abstract: Purpose: To compare the effect of different surface treatments on the bond strength of CAD/CAM fabricated resin-based and prefabricated fiber posts to root canal dentin. Methods: 160 single-rooted human teeth were selected and received endodontic treatment. The teeth were divided into four groups according to the post material used: (1) Prefabricated fiber-reinforced composite post (Snowpost), (2) CAD/CAM nanoceramic (Cerasmart), (3) CAD/CAM polymer infiltrated ceramic (Vita Enamic) and (4) CAD/CAM resin nanoceramic (Lava Ultimate). Then the posts were randomly assigned into four sub-groups according to the surface treatment method used: (1) Control (no treatment), (2) Laser (Er,Cr:YSGG laser device, Waterlase), (3) Hydrofluoric acid treatment [9.6% HF (Pulpdent) for 2 minutes], and (4) Sandblasting (50 μm Al₂O₃). Following post space preparation, posts were cemented with dual-cure resin cement (Panavia SA cement plus). From each root, five 1 mm-thick slices were obtained. The micropush-out bond strength test was performed for each slice. Data were analyzed by using two-way ANOVA and Tukey HSD tests. The fracture modes were evaluated under a stereomicroscope. Representative specimens were analyzed with SEM following surface treatments. Results: Micropush-out bond strength of posts to dentin was significantly affected by the type of post material (P< 0.05), but not by the surface treatment (P= 0.397). (Am J Dent 2019;32:113-117).

 

 

Mail: Dr. Isil Cekic-Nagas, Department of Prosthodontics, Faculty of Dentistry, Gazi University, Bişkek Cd.(8.Cd.) 82.Sk. No:4 06510 Emek, Ankara, Turkey. E-mail: isilcekic@gmail.com

 

 

 

Functionalized silk dental floss as a vehicle for delivery of bioactive minerals and ions to the tooth surface

 

Grigoriy Sereda, phd,  Khaled Rashwan, phd, Shahaboddin Saeedi, bs,  David Christianson, bs, Seth Fraser   &  Brennan Jordan, phd

 

Abstract: Purpose: To enable the commercially available silk dental floss to carry a series of desensitizing, alkalizing, and tooth strengthening pharmacons. Methods: The hydroxy-groups of the serine and tyrosine residues of the commercial silk dental floss were exposed by degumming, and employed as the chemical anchors for the introduction of carboxy-groups to the surface. The affinity of the silk dental floss to a set of bioactive species was studied by SEM, EDS, and XFS. The acetylated silk was used as a control sample for the experiments elucidating the effect of the surface carboxy-groups on its affinity to a series of pharmacons. Results: While unmodified silk has affinity to microcrystals of sodium carbonate, some affinity to hydroxyapatite particles and Sr²⁺, its carboxylation drastically increased the affinity to hydroxyapatite, Sr²⁺, Ca²⁺ and K⁺. The unmodified silk had some affinity to existing hydroxyapatite particles, but did not initiate the growth of hydroxyapatite on the surface. Carboxylation of silk enabled the growth of hydroxyapatite on its surface, and significantly increased its affinity to the existing hydroxyapatite particles. The unmodified silk had significant affinity to Zn²⁺, which exceeded its acylated derivatives. (Am J Dent 2019;32:118-123).

 

 

Mail:  Dr. Grigoriy Sereda, Department of Chemistry, University of South Dakota, 414 East Clark Street, Vermillion, SD 57069, USA.  E-mail:  Grigoriy.Sereda@usd.edu

 

 

 

 

 

At-home, in-office and combined dental bleaching techniques using hydrogen peroxide: Randomized clinical trial evaluation of effectiveness, clinical parameters and enamel mineral content

 

Ana Victoria Dourado Pinto, dds, Natália Russo Carlos, dds, Flávia Lucisano Botelho do Amaral, dds, msc, phd, Fabiana Mantovani Gomes França, dds, msc, phd, Cecilia Pedroso Turssi, dds, msc, phd &  Roberta Tarkany Basting, dds, msc, phd

 

Abstract: Purpose: To conduct a clinical evaluation of dental bleaching techniques using hydrogen peroxide (HP), regarding tooth sensitivity, gingival irritation, subject’s perception of color change, and calcium (Ca) and phosphorous (P) concentrations in enamel. Methods: 75 volunteers were distributed according to the bleaching technique (n=25): (a) at-home: 10%HP (Opalescence GO) for 15 days of continuous use (1 hour per day); (b) in-office: 40%HP (Opalescence Boost) in three clinical sessions (40 minutes each session); (c) combined: one initial session with 40%HP, and the rest with 10%HP for 15 days of continuous use. Clinical evaluations and Ca and P concentration collections were obtained before, during bleaching treatment, and 15 days after conclusion of treatment. The generalized linear models were used to evaluate the data for VITA Classical scale, CIELAB, tooth sensitivity, degree of acceptability of the technique, Ca and P concentrations and to determine the ΔE variables and color change perception. Gingival irritation was analyzed by Fisher’s Exact test. The total frequencies for each time interval (regardless of bleaching technique) were compared at 50% by the chi-square test. Results: The in-office technique presented the lowest tooth sensitivity, but all techniques caused an increase in sensitivity over time (P< 0.0001). All techniques resulted in lower Ca and P concentrations in enamel at each time point, compared with the baseline concentrations. Calcium concentrations did not differ significantly among the treatments (P= 0.9360). Phosphorus concentration at the 8^th day was higher for the in-office technique group (P< 0.05). All the bleaching techniques were effective in altering color, with ΔE values higher than 3.3, without any significant differences (P= 0.3255). Higher occurrence of gingival irritation was observed for at-home and combined techniques. The combined technique seemed to promote a color change faster than the other techniques. (Am J Dent 2019;32:124-132).

 

 

 

 

Mail: Profa. Dra. Roberta Tarkany Basting, Department of Restorative Dentistry, Faculty of Dentistry and Institute of Research, Rua José Rocha Junqueira, 13, Bairro Swift, Campinas, SP CEP: 13045-755, Brazil. E-mail: rbasting@yahoo.com

 

 

In vitro dentin tubule occlusion by an arginine-containing dentifrice

 

Peiyan Yuan, dds, msc,  Weiying Lu, dds, msc,  Haoyan Xu, dds, msc,  Jianzhen Yang, dds, msc, phd, Chenxia Liu, dds, msc, phd  &  Pingping Xu, dds, msc, phd

 

Abstract: Purpose: To evaluate the ability of an arginine-containing dentifrice to occlude dentin tubules. Methods: Dentin discs were divided equally into premolar and molar groups, which were then utilized in three treatment groups: a blank control group (distilled water treatment), a negative control group (common dentifrice with calcium carbonate) and an experimental group [dentifrice with 8% (w/w) arginine]. Each dentin disk was brushed with the dentifrice twice daily for 7 consecutive days. After this period, each disc was separated into two equal halves. One half was used for scanning electron microscopy (SEM) and energy-dispersive spectrometer (EDS) examinations, while the other half was brushed with distilled water twice daily for another 7 days prior to SEM observation. Results: The plugging rate in the arginine dentifrice group was significantly higher and more sustainable than in the negative control group. The surface deposition of calcium and phosphorus on the dentin discs in the arginine dentifrice group was also significantly higher. (Am J Dent 2019;32:133-137).

 

 

Mail: Dr. Pingping Xu, Department of Oral and Maxillofacial Surgery, Stomatological Hospital, Southern Medical University, 366 Jiangnandadao Road, Guangzhou, China. E-mail: pingpingxukqyy@163.com

 

 

 

The erosion protection efficacy of a stabilized stannous fluoride dentifrice: An in situ randomized clinical trial

 

Nicola X. West, bds, fds rcs phd, fds (rest dent), Nikki Hellin, rdn, Rachelle Eusebio, mas  &  Tao He, dds, phd

 

Abstract: Purpose: To compare the enamel protection efficacy of a stabilized stannous fluoride dentifrice to a triclosan-containing sodium fluoride dentifrice using a 10-day in situ erosion model, in accordance with the American Dental Association Seal of Acceptance guidelines for enamel erosion control. Methods: In this single-center, double-blind, randomized, supervised-usage, two-treatment, four-period, crossover study, healthy adult subjects were randomized to a treatment sequence involving the following products: a 0.454% stannous fluoride (1,100 ppm F) dentifrice (Procter & Gamble) and a control dentifrice containing 0.243% sodium fluoride (1,100 ppm F) and 0.3% triclosan (Colgate-Palmolive). Each study period consisted of 10 treatment days. Subjects wore an intra-oral appliance fitted with two polished human enamel samples for 6 hours per treatment day. While wearing the appliance, subjects swished with their assigned dentifrice slurry for 60 seconds twice daily and with 250 ml orange juice over a 10-minute period four times daily. After 10 days, enamel specimens were removed and measured for surface loss using contact profilometry. Results: 36 subjects were enrolled and 33 completed the study (mean age = 41.8 years). The stannous fluoride dentifrice demonstrated 90.3% less enamel loss than the NaF/triclosan dentifrice (P < 0.001) at Day 10, with median enamel loss of 0.279 µm and 2.877 µm, respectively. Both products were well tolerated. (Am J Dent 2019;32:138-142).

 

 

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

 

 

 

Effect of silver diamine fluoride and potassium iodide on bonding to demineralized dentin

 

MARK VAN DUKER, BA,  JURI HAYASHI, DDS, PHD,  DANIEL C. CHAN, DMD, MS, DDS,  JUNJI TAGAMI, DDS, PHD & ALIREZA SADR, DDS, PHD

 

ABSTRACT: Purpose: To evaluate the microtensile bond strength (MTBS) of resin composite to demineralized dentin treated with SDF or SDF-KI. Methods: Occlusal enamel of 30 caries-free extracted human molars was removed to expose flat dentin surfaces. Specimens were immersed in demineralizing solution (pH 4.5) for 7 days. A standard smear layer was created using 600-grit silicon carbide paper. Specimens were distributed into three groups (n=10). Control: Dentin rinsed with deionized water; SDF: Dentin treated with 38% SDF; and SDF-KI: Dentin treated with SDF and KI. Specimens were bonded with composite using Scotchbond Universal in etch-and-rinse mode. MTBS beams were prepared from each specimen after 24 hours and tested. Data was analyzed by one-way ANOVA with Tukey HSD post-hoc test. Results: MTBS test results ranged from 0 to 40 MPa. The highest values were obtained in the Control and lowest in SDF-KI, where pre-test failures were frequently observed. One-way ANOVA showed a significant difference among groups (P< 0.005); post-hoc analysis suggested no statistical difference between Control and SDF, but both groups showed higher MTBS compared with SDF-KI. (Am J Dent 2019;32:143-146).

 

 

Mail: Dr. Alireza Sadr, Biomimetics Biomaterials Biophotonics Biomechanics & Technology (B4T) Laboratory, Department of Restorative Dentistry, University of Washington, 1959 NE Pacific St. Box 357456, Seattle, WA 98195, USA. E-mail: arsadr@uw.edu

 

 

 

Effect of endodontic retreatment on the bond strength of resin cements to root canal dentin

 

Kamila de F. Pereira, dds, msc, Ana Carolina Venção, dds, msc, Miriam G. Magro, dds, msc, Lauriê G. Belizário, dds, msc, Thiago S. Porto, dds, msc, phd, Marcelo F. de Andrade, dds, msc, phd, Marco Antônio H. Duarte, dds, msc, phd  &  Milton C. Kuga, dds, msc, phd

 

Abstract: Purpose: To evaluate the effect of endodontic retreatment on the bond strength of different cementation techniques (self-adhesive and conventional resin cement) through the push-out mechanical testing and the penetrability of resin cements to root dentin. Methods: 60 human teeth with single oval-shaped canals were used (n=15): G1 - Endodontic treatment and cementation with RelyX ARC (ETA); G2 - Endodontic treatment and cementation with U200 (ETU); G3 - Endodontic retreatment and cementation with RelyX ARC (ERA); G4 - Endodontic retreatment and cementation with U200 (ERU). The groups with conventional endodontic treatment were filled with AH plus (ETA and ETU), while the groups that were submitted to endodontic retreatment were initially filled with Endofill and afterwards with AH Plus. Each radicular third (cervical, middle, and apical, of each tooth) was submitted to push-out bond strength testing, followed by evaluation with confocal laser microscopy to determine the penetration of the resin cements, and scanning electron microscopy was used to evaluate the failure mode. The parametric data were evaluated by two-way ANOVA and Tukey tests, and non-parametric data by Kruskal-Wallis and Dunn tests (α< 0.05). Results: The ETA group had higher bond strength values to intra-radicular dentin than the other groups in all root thirds (P< 0.05). Endodontic retreatment had a negative impact on the penetration and push-out bond strength of RelyX ARC and U200 cement, regardless of the analyzed radicular third. (Am J Dent 2019;32:147-151).

 

 

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

 

 

Cytotoxic effects of silver diamine fluoride

 

Mary E. Fancher, dds, ms,  Suzanne Fournier, dds,  Janice Townsend, dds, ms   &   Thomas E. Lallier, phd

 

Abstract: Purpose: To investigate the effect of silver diamine fluoride (SDF) and fluoride varnish (FV) on human gingival fibroblasts (HGF) and bacteria. Methods: HGF cell viability was assessed after exposure to various dilutions of SDF or FV. Hydroxyapatite (HA) discs treated with SDF, FV, or saline were rinsed in artificial saliva for 84 days. HGF were exposed to treated discs and viability assessed fluorescently. Oral bacteria were exposed to treated discs and survival quantified. Results: At 0.01%, SDF was almost 100% cytotoxic to HGF. SDF and FV treated HA discs, induced near-complete cell death after 24 hours of contact. After rinsing FV discs for 21 days, cell survival exceeded 95%. SDF treated discs were toxic to HGF and bacteria after 9 weeks of rinsing. (Am J Dent 2019;32:152-156).

 

 

Mail: Dr. Janice Townsend, Department of Pediatric Dentistry, College of Dentistry, The Ohio State University, 4126 Postle Hall, 305 W. 12th Ave., Columbus, OH 43210-1267, USA.  E-mail: townsend.661@osu.edu