Oral B Genius


December 2016 Abstracts



Clinical evaluation of a toothpaste containing lysozyme for the treatment of recurrent aphthous stomatitis: A 3-month, double-blind, randomized study


Yanxiong Shao, mmed  &  Haiwen Zhou, dds


Abstract: Purpose: To assess the efficacy and safety of a toothpaste containing lysozyme for the treatment of minor recurrent aphthous stomatitis (MiRAS) in a 3-month clinical trial. Methods: 71 participants with MiRAS were recruited to this randomized, parallel-controlled, double-blind clinical trial. Participants were allocated randomly to the test group or the control group. Demographic data and pain score (visual analogue scale, VAS) were recorded at baseline. Healing time of MiRAS, recurrence frequency and side effects were recorded at the 1-, 2- and 3-month follow-up visits. All data were analyzed using SAS software version 8.0. Results: There was no significant difference (P> 0.05) in pain score between the treatment group (3.00 ± 1.66) and the control group (2.66 ± 1.51). The average healing time was significantly reduced (P< 0.01) in the treatment group (5.66 ± 2.02) compared with the control group (7.46 ± 2.69), while the recurrence frequency also showed a significant reduction from 4.40 ± 2.89 in the control group to 3.06 ± 1.48 in the treatment group (P< 0.05). No obvious side effects were observed. (Am J Dent 2016;29:303-306).


Clinical significance: The results of this clinical study supported the conclusion that a toothpaste containing lysozyme was effective in promoting healing and reducing recurrence frequency without significant side effects in the treatment of minor recurrent aphthous stomatitis.


Mail: Dr. Haiwen Zhou, Department of Oral Mucosal Diseases, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, 500 Qu-xi Road, Shanghai, 200011, PR China. E-mail:



The influence of the utilization time of brush heads from different types of power toothbrushes on oral hygiene assessed over a 6-month observation period: A randomized clinical trial


Jan Schmickler,  Sabine Wurbs, dr med dent,  Susanne Wurbs, dr med dent,  Katharina Kramer, dr rer nat, Sven Rinke, pd dr med dent,  Else Hornecker, dr med dent,   Rainer F. Mausberg, pd dr med, dent &  Dirk Ziebolz, pd dr med dent


Abstract: Purpose: This randomized clinical trial investigated the influence of the utilization time of brush heads from different types of power toothbrushes [oscillating rotating (OR) and sonic action (SA)] on oral hygiene (plaque accumulation and gingival inflammation) over a 6-month observation period. Methods: 49 participants were randomly allocated into two groups: use of the same brush head over 6 months (NR: non-replacement) or replacement of brush head every 4 weeks over 6 months (R: replacement). Each group was subdivided into two subgroups according to kind of toothbrush (TB) used (OR and SA). Modified Quigley-Hein plaque index (QHI), papilla bleeding index (PBI), and gingival index (GI) were recorded at baseline and 2, 8, 12, 16, and 24 weeks after baseline. After 24 weeks, participants of both groups (R and NR) received a new brush head. At week 26, final QHI, PBI, and GI were recorded. Results: QHI decreased between baseline and follow-up visits in R groups (P< 0.05), with the exception of week 12 (P= 0.26). In NR groups, no significant decrease was detected (P> 0.05). There was no significant effect of time on PBI or GI in any of R subgroups (P> 0.05). In NR oscillating/rotating TB: significant increase in PBI and GI was detected 24 weeks after baseline (PBI: P= 0.02, GI: P= 0.03); sonic action TBs showed significant decrease in PBI at every follow-up visit (P< 0.05), except at 24 weeks after baseline (P= 0.73). GI was significantly decreased at 2 weeks after baseline only (P< 0.01). (Am J Dent 2016;29:307-314).


Clinical significance: Six-month use of the same brush head reduced effectiveness in removing plaque, and gingival inflammation appeared to increase after a utilization time of over 4 months. Replacing brush heads is advised after 4 months.


Mail: PD Dr. Dirk Ziebolz, Dept. of Cariology, Endodontology and Periodontology, University Leipzig, Liebigstr. 12, D 04103 Leipzig, Germany. E-mail:



Antimicrobial and antibiofilm activity of silver, titanium dioxide and iron nano particles


Fatemeh  Lavaee, dmd, phd,  Kiana  Faez,  Kioumars Faez,   Nahal  Hadi, bsc, msc, phd &  Farzan  Modaresi, bsc, msc, phd


Abstract: Purpose: To compare the antimicrobial effects of chlorhexidine, penicillin, erythromycin, clindamycin, tetracycline and vancomycin with silver, titanium dioxide and iron nanoparticles and also to consider the synergistic antibacterial and antibiofilm effects of nanoparticles in clinical and standard strains of Streptococcus mutans and Streptococcus sanguinis. Methods: The specimens collected from 66 3-5 year-old children with detected S. mutans and S. sanguinis by PCR were then exposed to the antimicrobial activity of chlorhexidine, penicillin, erythromycin, clindamycin, tetracycline and vancomycin with silver, titanium dioxide and iron nanoparticles measured by microdilution and disc diffusion tests and the colony counted after 1 to 5 minutes. The antibiofilm activity was examined by microtiter test. Results: Use of nanoparticles alone showed higher minimum inhibitory concentration (MIC) than using them synergistically. The most effective synergistic solution was the one containing TiO2, Ag and Fe3O4 showing 0.019 μg/ml in S. mutans and S. sanguinis. Furthermore, this solution had the lowest biofilm inhibitory concentration (BIC) and colony forming units than the other antibiotics and chlorhexidine. (Am J Dent 2016;29:315-320).


Clinical significance: The solution containing TiO2, Ag and Fe3O4 showed the lowest inhibitory and antibiofilm concentration against S. mutans and S. sanguinis compared to those of other nanoparticle containing solutions, antibiotics and chlorhexidine, thus it may be used for treating dental caries, dental plaque and oral infections.


Mail: Dr. Farzan Modaresi, Department of Microbiology, School of Medicine, Jahrom University of Medical Sciences, Jahrom, Iran.  E-mail:,



Quantitation of endotoxin and lipoteichoic acid virulence using toll receptor reporter gene


Tom Huggins, phd, John CHRISTIAN Haught, phd, Sancai Xie, phd, Cheryl S. Tansky, ms, Malgorzata  Klukowska, phd, dds, Melanie C. Miner, bs, ba  &  Donald J. White, phd


Abstract: Purpose: To apply quantitative Toll-like receptors (TLR) cell assays to compare lipopolysaccharides (LPSs) and lipoteichoic acids (LTAs) from different oral bacterial strains for potential pathogenicity in vitro. Methods: The potency of LPS and LTA from different bacteria on activation of TLR reporter genes in HEK-tlr cell lines was examined. P. gingivalis LPS mix, P. gingivalis 1690 LPS, P. gingivalis 1435/50 LPS, E. coli LPS (E. coli K12), B. subtilis LTA, S. aureus LTA, E. hirae LTA and S. pyogenes LTA were examined in both TLR2 and TLR4 HEK cell line reporter assays. Solutions of LPS and LTA from selected bacteria were applied in a dose response fashion to the TLR reporter cells under standard culture conditions for mammalian cells. Reporter gene secreted-embryonic-alkaline-phosphatase (SEAP) was measured, and half maximal effective concentration (EC50) was determined for each sample. Concentration dependent TLR activation was compared to similar responses to LPS and LTA for commercial BODIPY-TR-Cadaverine and LAL biochemical (non cell based) assays. Results: All LPS from P. gingivalis activated both TLR2 and TLR4 responses. E. coli LPS is a strong activator for TLR4 but not for TLR2 responses. In contrast, both B. subtilis and S. aureus LTA provoked responses only in TLR2, but not in the TLR4 assay. Interestingly, E. hirae LTA and S. pyogenes LTA did not stimulate strong TLR2 responses. Instead, both E. hirae LTA and S. pyogenes LTA mounted a reasonable response in TLR4 reporter gene assay. Both LPS and LTA showed deactivation of fluorescence in BODIPY-TR-Cadaverine while only LPS was active in LAL. As with biochemical assays, an EC50 could be determined for LPS and LTA from various bacterial strains. The EC50 is defined as a concentration of LPS or LTA that provokes a response halfway between the baseline and maximum responses. Lower EC50 means higher potency in promoting TLR responses, and in principle indicates greater toxicity to the host. (Am J Dent 2016;29:321-327).





Clinical significance: InvivoGen TLR2 and TLR4 assays distinguish specific types of microbial products, such as LPS and LTA from different bacteria. Application of EC50 determinations creates a means for quantitative and comparisons of LPS and LTA virulence in a cellular-based assay and combinations of TLR reporter cell assays along with biochemical evaluation of LPS/LTA in BODIPY-TR-Cadaverine and LPS in LAL assays provides a means to quantitate virulence of plaque samples with respect to both LPS and LTA. These learnings have long-term implications for patient care in that understanding the virulence of patients’ plaque provides important information to assess risk of oral diseases.


Mail:  Dr. Tom Huggins, Procter & Gamble, Mason Business Center, 8700 Mason-Montgomery Road, Mason, OH, 45040, USA.  E-mail:



Lipopolysaccharide and lipoteichoic acid binding by antimicrobials used in oral care formulations


John Christian Haught, phd,  Sancai Xie, phd,  Ben Circello, phd,  Cheryl S. Tansky, ms,   Deepa Khambe, ms, Yiping Sun, phd, Yakang Lin, ms,  Koti Sreekrishna, phd,  Malgorzata Klukowska, phd, dds, Tom Huggins, phd  &  Donald J. White, phd


Abstract: Purpose: To study the reactivity of lipopolysaccharide (LPS) and lipoteichoic acid (LTA) with the cationically charged agents cetylpyridinium chloride, stannous fluoride, and the non-cationic agent triclosan. We also assessed the effect of these agents to inhibit LPS and LTA binding to cellular Toll-like Receptors (TLRs) in vitro. Methods: The ability of these antimicrobials to bind with LPS and/or LTA was assessed in both the Limulus amebocyte lysate and BODIPY-TR-cadaverine dye assays. Mass spectroscopy was then used to confirm that stannous fluoride directly binds with LPS and to determine stoichiometry.  Lastly, we looked for possible inhibitory effects of these antimicrobial agents on the ability of fluorescently conjugated LPS to bind to TLR4 expressed on HEK 293 cells. Results: Cetylpyridinium chloride (CPC) and stannous salts including stannous fluoride interfered with LPS and LTA reactivity in both dye assays, while triclosan had no effect. Mass spectroscopy revealed direct binding of stannous fluoride with E. Coli LPS at 1:1 stoichiometric ratios. In the cellular assay, cetylpyridinium chloride and stannous fluoride, but not triclosan, inhibited LPS binding to TLR4. (Am J Dent 2016;29:328-332).



Clinical significance: These results support a potential mechanism of action for stannous fluoride and CPC formulated in oral products in which these ingredients bind bacterial toxins and potentially render them less toxic to the host. These results may influence home care recommendations for patients at risk for plaque-related diseases.



Mail: Dr. Chris Haught, The Procter & Gamble Company, 8700 Mason Montgomery Road, Mason, OH 45040, USA. E-mail:



The new generation of conventional and bulk-fill composites do not reduce the shrinkage stress in endodontically-treated molars


Laís  Rani  Sales  Oliveira  Schliebe, dds,  Stella  Sueli  Lourenço  Braga, dds, ms, Renata  Afonso  da  Silva  Pereira, dds, ms, phd,  Aline  Arêdes  Bicalho, dds, ms, phd, Crisnicaw  Veríssimo, dds, ms, phd,  Veridiana  Resende  Novais, dds, ms, phd,  Antheunis  Versluis, phd &  Carlos  José  Soares, dds, ms, phd


Abstract: Purpose: To compare flowable and regular paste bulk-fill resin composites with old and new generation conventional composites that use incremental filling techniques for direct restoration of endodontically-treated teeth. Methods: Four resin composites produced by the same company (3M-ESPE) were used: two conventional resin composites (old formulation, Z100, and new nanofilled formulation, Filtek Supreme XT); and two bulk-fill resin composites (flowable composite, Filtek Bulk-fill Flowable associated with Filtek Supreme, and regular paste, Filtek Bulk-fill Posterior). Elastic modulus (E), Vickers hardness (VH), post-gel shrinkage (Shr), diametral tensile strength (DTS) and compressive strength (CS) were determined (n= 10) and statistically analyzed using ANOVA and Tukey’s test (α=0.05). Shrinkage stresses were analyzed using non-linear finite element analysis. Results: Filtek Bulk-fill flowable and Filtek Supreme XT had higher CS than Z100 and Filtek Bulk-fill Posterior. Z100 and Filtek Supreme XT had higher DTS than Filtek Bulk-fill Posterior. Filtek Bulk-fill flowable had the lowest values and Z100 the highest E and Shr. Z100 resulted in higher stresses in the enamel and in root dentin close to the pulp chamber than the other filling techniques. Filtek Bulk-fill Flowable resulted in lower stress than other resin composites. (Am J Dent 2016;29:333-338).



Clinical significance: Using bulk-fill composites, especially flowable resin composite, created lower stresses in restored endodontically-treated teeth. Clinicians, when deciding for direct restoration of endodontically-treated teeth, may choose the bulk-fill composite to decrease undesirable effects of direct restoration while simplifying filling procedure.



Mail: Dr. Carlos José Soares, Federal University of Uberlândia, School of Dentistry, Avenida Pará, 1720, Bloco 4L, Anexo A, Sala 42, Campos Umuarama, Uberlândia, Minas Gerais, 38400-902 Brazil.  E-mail:



Case-specific finite element analysis of dental CAD/CAM prostheses to identify design flaws prior to manufacture


Davide Apicella, dds, phd, Tim Joda, dmd, msc, Gianni Bonadeo, dt, Roberto Sorrentino, dds, msc, phd &  Marco Ferrari, md, dds, phd


Abstract: Purpose: To apply a design optimization strategy to dental prostheses machining to verify whether this approach can detect flaws occurring in the CAD process and to estimate the influence of the type of material on the occurrence of fractures in restorations. Methods: The stereo lithography interface format of a 4-unit (from canine to first molar) fixed dental prosthesis designed by a conventional dental CAD process was converted into a Finite Element Analysis (FEA) model. This basic model was coupled to the mechanical properties of feldspathic ceramic, lithium disilicate ceramic (LS2) and zirconia (ZrO2) to create three FEA models with different mechanical properties. The models were constrained along the abutment housing surfaces of the canine and the first molar, respectively. Finally, a simulated load of 50 N was applied vertically to the occlusal surface of the first premolar. Results: The FEA showed a stress peak concentration between the second connectors and the second premolar. The stress peak overcame the ultimate tensile stresses of feldspathic and lithium disilicate ceramics; conversely, the ultimate tensile stress of zirconia was not overcome. A geometrical flaw was identified in the 4-unit fixed dental prosthesis. The flaw was sensitive to tensional stress and could lead to failure of the component. (Am J Dent 2016;29:339-344).



Clinical significance: The results of the present investigation showed the importance and future impact of the application of FEA in the daily practice of prosthodontics. A FEA-implemented CAD process would allow proper prosthetic volumes with correct dimensions of the framework, in order to withstand occlusal loads and consequently reduce mechanical failures. FEA is a useful tool to simplify the design of prosthetic frameworks and select esthetic ceramic materials with strength enough to withstand occlusal stress.



Mail: Prof. Dr. med. dent. Marco Ferrari, Department of Prosthodontics & Dental Materials, School of Dental Medicine, University of Siena, Viale Bracci 1, 53100 Siena, Italy.  E-mail:




Effects of desensitizing toothpastes on the permeability of dentin after different brushing times: An in vitro study


Meng Yang, ms,  Hong Lin, dds, phd,  Ruodan  Jiang, ms  &  Gang Zheng, dds, phd


Abstract: Purpose: To investigate the effects of three commercially available desensitizing toothpastes on dentin permeability, and compare the efficacy of each product for reducing dentin permeability in the short term according to the frequency and duration of usage. Methods: 100 dentin discs with no caries were prepared from freshly extracted human third molar teeth. The dentin discs were brushed with three desensitizing toothpastes or with a non-desensitizing toothpaste and distilled water, which served as control. The 100 dentin slices were randomly divided into two groups (n= 50): one group underwent continuous brushing (brushed for 3 minutes continuously), and the other group underwent discontinuous brushing (brushed three times, each time for 1 minute). Then, the two groups were divided into five subgroups (n = 10) for the five brushing applications. Dentin permeability was measured with a hydraulic permeability system before and after brushing. Results: All desensitizing toothpastes reduced dentin permeability significantly after treatment. Sensodyne Repair & Protect (calcium sodium phosphosilicate) and discontinuous brushing reduced dentin permeability significantly compared with continuous brushing. Dentin permeability values showed no significant difference between the three toothpastes after 3 minutes of continuous brushing. When comparing the three toothpastes under discontinuous brushing conditions after 3 minutes, Sensodyne Repair & Protect (calcium sodium phosphosilicate) reduced dentin permeability significantly. (Am J Dent 2016;29:345-351).




Clinical significance: Sensodyne Repair & Protect (calcium sodium phosphosilicate) and discontinuous brushing reduced dentin permeability significantly compared with continuous brushing. Moreover, brushing with Sensodyne Repair & Protect (calcium sodium phosphosilicate) resulted in the lowest dentin permeability compared with those of the other two toothpastes. These results indicated that Sensodyne Repair & Protect may relieve dentin hypersensitivity.



Mail: Dr. Gang Zheng, Department of Dental Materials, School of Stomatology, Peking University, 22 South Zhongguancun Avenue, Haidian District, Beijing 100081, PR China.  E-mail:


Effect of radiotherapy, adhesive systems and doxycycline on the bond strength of the dentin-composite interface


Eveline Freitas Soares, dds, ms  Lucas Zago Naves, dds, ms, phd, Américo Bortolazzo Correr, dds, ms, phd, Ana Rosa Costa, dds, ms, phd, Simonides Consani, dds, ms, phd, Carlos José Soares, dds, ms, phd, Franklin Garcia-Godoy, dds, ms, phd, phd  &  Lourenço Correr-Sobrinho, dds, ms, phd


Abstract: Purpose: To investigate the effect of radiotherapy, doxycycline and adhesive systems on the microtensile bond strength (μTBS) of the dentin-composite interface. Methods: 60 human third molars were sectioned to expose middle dentin surface and distributed according to: (1) adhesive system (Adper Scotchbond MP and Clearfil SE Bond) applied, (2) application or not of doxycycline, and (3) submission to 60 Gy total radiation (2 Gy daily doses, 5 days/week for 6 weeks) before restoration procedure (RtRes); after restoration procedure (ResRt) or not submitted to radiotherapy (Control group). Specimens were tested for μTBS and mode of failure were evaluated under optical microscopy. The bonding interface was evaluated with a scanning electron microscope (SEM). Data was submitted to three-way ANOVA and Tukey’s test (α= 0.05). Results: There was no significant difference between the μTBS (MPa) of Adper Scotchbond MP (25.5±11.1) and Clearfil SE (27.6±9.1). Control (30.5±10.9) and ResRt (29.2±10.4) presented μTBS significantly higher than RtRes (23.1±7.2). Doxycycline (21.7±7.6) significantly reduced μTBS compared to groups without doxycycline application (33.6±8.6). Dentin cohesive failure mode was predominant for RtRes and mixed failure mode for ResRt. Mixed and adhesive failures were frequently observed in control groups. SEM showed adhesive penetration in dentin tubules in all groups, regardless of the radiotherapy and the application of doxycycline. The radiotherapy before composite restoration procedure decreased the µTBS. No statistical difference was observed between the adhesive systems. The doxycycline reduced µTBS regardless of the other conditions. (Am J Dent 2016;29:352-356).


Clinical significance: Composite restoration procedure should be done before radiotherapy, regardless of the adhesive system used.


Mail: Dr. Lourenço Correr-Sobrinho, Limeira Avenue, 901, Vila Rezende, Areiao, Piracicaba, São Paulo, Brazil, 13414-903. E-mail:


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