^{August 2015 Abstracts}

 

Physical effects of non-cavitated explorer probing on enamel

smooth-surface carious lesions

 

Daniel  W. Boston, dmd   &  Steven  R.  Jefferies, ms, dds, phd

 

Abstract: Purpose: To assess the physical effects of explorer probing on non-cavitated smooth-surface enamel carious lesions. Methods: Extracted teeth with white enamel decalcification (ICDAS 2) were used. Indentations were made in decalcified and non-decalcified regions with a #23 explorer using “scratch” or “poke” application and 100g, 300g or 600g force. Specimens were imaged with SEM and polarizing light microscopy. Indentation widths were measured digitally. Two-way ANOVA with pair-wise comparisons was used to assess interactions of force and enamel condition (normal or carious) on indentation groove width. Results: No or minimal effect was seen on normal enamel surface morphology. For the decalcified regions, defects were seen in SEM and polarizing light images. Findings included a smear layer, open clefts, lateral debris and micro-fractures. Two-way ANOVA for effects of force and enamel quality on mean groove width showed statistically significant differences for both variables for all teeth tested. (Am J Dent 2015;28:183-187).

 

 

Mail: Dr. Daniel W. Boston, Department of Restorative Dentistry, Temple University Kornberg School of Dentistry, 3223 North Broad Street, Philadelphia, PA 19140, USA.  E-mail:  daniel.boston@temple.edu

 

 

Confirmation of efficacy in providing relief from the pain of dentin

hypersensitivity of an anhydrous dentifrice containing 0.454% with or

without stannous fluoride in an 8-week randomized clinical trial

 

Charles  R.  Parkinson, phd,  Peter  Jeffery, pgdip,  Jeffery  L.  Milleman, dds, mpa,

Kimberly  R.  Milleman, rdh, bsed, ms  &  Stephen  Mason, phd

 

Abstract: Purpose: To compare the efficacy of an anhydrous dentifrice containing 0.454% w/w stannous fluoride and a negative control dentifrice containing 1,000 ppm fluoride, as sodium monofluorophosphate, at reducing dentin hypersensitivity over 8 weeks with twice-daily brushing. Methods: This was a randomized, examiner-blind, parallel, two treatment group, stratified (by maximum baseline Schiff sensitivity score), 8-week clinical study carried out at a single site in 119 healthy subjects with at least two sensitive teeth, who met all study criteria at the screening and baseline visits. Clinical assessments of sensitivity to evaporative (air) [with Schiff sensitivity score and visual analogue scale (VAS)] and tactile (Yeaple probe) stimuli were employed to compare the efficacy of the test dentifrice containing 0.454% w/w stannous fluoride to the negative control dentifrice at reducing sensitivity after 4 and 8 weeks treatment. Results: Of the 119 subjects randomized to study treatment, 113 completed the study. At 4 and 8 weeks, between treatment analyses found the test dentifrice to be significantly better than the negative control dentifrice in relieving dentin hypersensitivity for all measures (Schiff: P< 0.0001 at 4 and 8 weeks; VAS score: P= 0.0003 at 4 weeks, P< 0.0001 at 8 weeks; tactile threshold: P= 0.0138 at 4 weeks, P< 0.0001 at 8 weeks). (Am J Dent 2015;28:190-196).

 

 

Mail: Dr. Charles Parkinson, GSK Consumer Healthcare, St Georges Avenue, Weybridge, KT13 0DE, United Kingdom. E-mail: charles.x.parkinson@gsk.com

 

Gingival health benefits of essential oil, 0.075% cetylpyridinium chloride

and control mouthrinses: A 4-week randomized clinical study

 

Christine  Ann  Charles, rdh,  Jose  Roberto  Cortelli, dds, phd,  Davi  Aquino, dds, phd,  Ratna  Revankar, phd &  Mei  Miau  Wu, drph

 

Abstract: Purpose: This randomized, single center, examiner-blind, controlled, parallel-group, 4-week clinical study compared the antiplaque/anti-gingivitis efficacy of an essential oil (EO) containing mouthrinse versus a 0.075% cetylpyridinium chloride (CPC) containing mouthrinse. A 5% hydroalcohol solution was included as a control group. Methods: 165 systemically healthy volunteers (18-72 years of age), with mild to moderate plaque-related gingivitis were enrolled in this clinical trial; 162 subjects completed the study. At baseline and 4-week visits, subjects received an oral examination, gingivitis (MGI), gingival bleeding (BI) and plaque (PI) assessments. Following randomization, subjects began rinsing with 20 mL of the assigned mouthrinse for 30 seconds, in conjunction with their usual oral hygiene, twice daily for the duration of the study. Results: All rinses were well tolerated by the subjects. EO was statistically significantly superior to CPC with a reduction in mean MGI of 5.9%, and in mean PI of 6.4%. Statistically significant reductions in gingivitis, bleeding and plaque were observed for both EO and CPC when compared to the negative control; mean MGI and mean PI were reduced by 13.0% and 18.9% for EO and by 7.6% and 13.3% for CPC. EO also statistically significantly reduced the proportion of gingival bleeding sites compared to CPC by 7.6% (P= 0.012) and compared to control by 10.6% (P< 0.001). For the post hoc sitewise analyses, at 4 weeks, the mean percentage of healthy sites for EO, CPC and Control were 7.4%, 1.1% and 0.8%, respectively and the mean percentage of virtually plaque free sites for EO, CPC and control were 5.4%, 3.8% and 0.4% respectively. The mean percentages of more inflamed gingival sites for EO, CPC and control were 20.4%, 26.2% and 45.7%, respectively. The mean percentage of tooth surfaces with heavier accumulations of plaque (PI scores ≥ 3) was 50.9% for EO, 56.1% for CPC and 81.1% for control. Reduction of gingival inflammation and dental plaque was statistically significantly superior for EO compared to both 0.075% CPC and negative control. Both marketed antimicrobial mouthrinses showed a beneficial result in gingival health and in reducing plaque accumulation as early as 4 weeks. (Am J Dent 2015;28:197-202).

 

 

Mail: Christine Charles, retired, Johnson & Johnson Consumer Inc., 185 Tabor Road (K2-212), Morris Plains, NJ 07950, USA. E-mail: duckcharles@yahoo.com

 

Does refurbishing composites lead to short-term effects or long-lasting

improvement?

 

Eduardo FernÁndez Godoy, dds,  Patricio VildÓsola Grez, dds,  Cristian Bersezio Miranda, dds,

Valeria V. Gordan, dds, ms, ms-ci,  Ivar A. MjÖr, prof emer,  Osmir Batista Oliveira Junior, dds, phd Claudia Letelier Pardo, dds,  Juan Estay Larenas, dds,  Gustavo Moncada CortÉs, dds 

&  Javier Martin Casielles, dds,

 

Abstract: Purpose: To evaluate the clinical performance of refurbished resin composite restorations compared to untreated (negative control) restorations over a period of 10 years. Methods: 26 subjects (having a total of 52 composite restorations) were recruited. All restorations in the refurbished group showed clinical features rated bravo according to modified USPHS criteria. Untreated restorations were those that had been deemed acceptable (alpha or bravo rated); these were used as controls. Two examiners performed assessments at baseline and during the 5^th and 10^th years after the intervention. Wilcoxon tests were performed for within-group comparisons, Friedman tests were used for multiple within-group comparisons, and Mann Whitney tests were used for between-groups comparisons. Kaplan-Meier survival curves were calculated, and the Mantel-Cox test was used to compare curves. P < 0.05 was considered statistically significant. Results: In both groups, 10-year scores were significantly different from baseline scores in all clinical parameters except secondary caries. There were no statistically significant differences in the survival analysis of groups (log-rank test, P= 0.376). Refurbishing treatment improved the anatomy, roughness, luster, and marginal adaptation of restorations with a short term effect, with most properties rated acceptable after 10 years of clinical service. The clinical characteristics were similar for all groups at the 10^th year. (Am J Dent 2015;28:203-208).

 

 

Mail:  Dr. Eduardo Fernández Godoy, Department of Restorative Dentistry, University de Chile, Dental School, Sergio Livingstone Pohlhammer 943, Independencia, Santiago, Chile.  E-mail:  edofdez@yahoo.com

 

Radiolucent halos beneath composite restorations do not justify restoration

replacement

 

Bruna Mua, dds, ms, Berenice Barbachan e Silva, dds, ms, phd, Vânia Regina Camargo Fontanella, dds, ms, phd,  Fernanda Cristina Mendes de Santana Giongo, dds, ms  &  Marisa Maltz, dds, ms, phd

 

Abstract: Purpose: To determine the correlation between the presence of radiolucent areas (RA) beneath composite restorations and gaps and remaining demineralized tissue (RDT). Methods: 50 extracted teeth (sound and carious) were studied. After caries removal, cavities were filled. Artificial cavities were created and filled in the sound teeth. Samples were sectioned and analyzed with stereomicroscopy. Results: Gap/RDT was observed in 38.9% [95% confidence interval (CI) =28.2–50.5] and  68.9% (95%CI=57–78.6) of sound and carious teeth, respectively, (P= 0.001). Gap/RDT was associated with RA (P< 0.001). Sensitivity, specificity, predictive positive values (PPV), predictive negative value, and accuracy for carious teeth were 77.1% (95%CI=63.7–87.3), 54.5% (95%CI=33.8–74.1), 78.7% (95%CI=65.3–88.7), 52.2% (95%CI=32.1–71.7), and 70% (95%CI=58.5–79.8), and for sound teeth were 73.7% (95%CI=62.9−82.6), 59.1% (95%CI=47.0−70.4), 67.5% (95%CI=56.9–76.9), 66.1% (95%CI=53.4−77.3), and 66.9% (95%CI=58.9−74.3). Only the PPV differed between the sound and carious teeth (P= 0.024).There was a correlation between radiolucency and gap/RDT, but a high number of false positives were found. (Am J Dent 2015;28:209-213).

 

 

Mail: Prof. Berenice Barbachan e Silva, Department of Social and Preventive Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Rua Ramiro Barcelos, 2492, CEP 90035-003, Bom Fim, Porto Alegre, RS, Brazil.  E-mail:  berenicebarbachanesilva@gmail.com

 

Influence of multi-step etch-and-rinse versus self-etch adhesive systems

on the post-operative sensitivity in medium-depth carious lesions:

An in vivo study

 

Nicola Scotti, dds,  Emanuele Bergantin, dds,  Roberta Giovannini, dds,  Laura Delbosco, dds,

Lorenzo Breschi, dds,  Giuseppe Migliaretti, phd,  Damiano Pasqualini, dds  &  Elio Berutti, md, dds

 

Abstract: Purpose: To evaluate the influence of a three-step etch-and-rinse versus a two-step self-etch adhesive system on immediate post-operative sensitivity. Methods: In total, 204 subjects with one posterior tooth affected by a primary carious lesion were recruited. The subjects were randomly divided into two groups, based on the two multi-step adhesive systems used: Group A (All Bond 3) and Group B (Clearfil Protect Bond). The same skilled operator carried out the restorations using a nano-hybrid composite (Venus Diamond) in oblique stratification. Each increment was light-cured for 20 seconds with a LED lamp (Translux Power Blue). Subjects received a three-level thermal sensitivity questionnaire for post-operative sensitivity ratings. The evaluations were recorded daily for 7 days. Scores were analyzed using the McNemar test and postoperative trends were analyzed with the Friedman test (P< 0.05). All (100%) enrolled subjects completed the follow-up visits. There was no statistically significant difference between the two groups in post-operative sensitivity trends. In both groups, increased post-operative sensitivity was found at D1, which then decreased significantly during the observation period. Results: The results of this in vivo study showed that both of the tested adhesives, etch-and-rinse or self-etch, provided effective dentin sealing, preventing subjects from experiencing post-operative sensitivity in the treatment of medium-depth cavities. (Am J Dent 2015;28:214-218).

 

 

Mail: Dr. Nicola Scotti, Via Nizza 230, 10126 Torino,  Italy.  E-mail:  nicola.scotti@unito.it

 

 

Influence of colorant solutions in properties of indirect resin composites

 

Daniela Micheline dos Santos, dds, msc, phd,  Adrielle Mendes de Paula, dds,

Liliane da Rocha Bonatto, dds,  Emily Vivianne Freitas  da Silva, dds,  Aljomar JosÉ Vechiato Filho, dds, msc,  AmÁlia Moreno, dds, msc  &  Marcelo Coelho Goiato, dds, msc, phd

 

Abstract: Purpose: To evaluate the influence of colorant solutions on color stability and surface roughness of indirect resin composites submitted to prior immersion in mouthwashes. Methods: Five brands of indirect resin composites were assessed: Adoro, Resilab, Cristobal, Sinfony and Epricord. The specimens were immersed in five different solutions (n= 10): four mouthwashes (Listerine, Oral-B, Plax, Periogard) and artificial saliva (control). 60 hours after immersion in mouthwashes, the specimens were exposed to coffee solution. Shade stability and surface roughness were tested by a spectrophotometer and by a profilometer, respectively. A three-way repeated-measures ANOVA was performed. Differ-ences between the values were compared by the Tukey-Kramer test (P< 0.05). Results: The majority of the specimens showed human-perceptible color change. Greater color change was observed after immersion in coffee, except for Cristobal. The color change was even higher for specimens previously immersed in mouthwashes. The Epricord resin showed the lowest roughness value and the Cristobal showed the highest value, regardless of the period. The highest roughness change occurred after immersion in Listerine. (Am J Dent 2015;28:219-223).

 

 

Mail:  Prof. Daniela Micheline dos Santos, Department of Dental Materials and Prosthodontics, Aracatuba Dental School, Univ. Estadual Paulista – UNESP, José Bonifácio St., #1193, Araçatuba, 16015-050, São Paulo, Brazil.  E-mail:  danielamicheline@foa.unesp.br

 

Application of ethanol improves the resin-dentin bond strength

of a two-bottle, self-etching primer-adhesive

 

Fengjuan  Cui,  Xiaoqiang  Liu, dds,  Lin  Ma, dds,  Ayaka  Chiba, Bingqing  Li,  Jianfeng  Zhou, dds, phd &  Jianguo  Tan, phd

 

Abstract: Purpose: To investigate whether the application of ethanol to a two-step self-etching adhesive can improve its resin-dentin bond performance. Methods: Four different ethanol concentrations were added to the adhesive of Clearfil SE Bond to create four ethanol primers (40, 60, 80 or 100% ethanol). 24 extracted third molars were divided into four groups. Each group corresponded to one of the four hydrophobic ethanol primer concentrations. The teeth in the control group were bonded with Clearfil SE Bond according to the manufacturer’s instructions. The primed teeth in the experimental groups were treated with the ethanol primer prior to application of the solvent-free adhesive. Microtensile bond strengths (mTBS) were tested 24 hours after specimen preparation. Another 14 teeth were bonded using the same methods to evaluate mTBS after 1 year. Nanoleakage was evaluated under field-emission scanning electron microscopy before and after aging. Results: In the 24-hour group, the mTBS in the 60% ethanol/40% adhesive primer group increased significantly (21.6%, P< 0.05) over the no ethanol control. After 12-month water storage, the bond strength of that experimental group was still higher than that of the control group (19.5%, P< 0.05). Before aging, the nanoleakage was clearly seen in the control group but hardly any was seen in the experimental group. After aging, the nanoleakage increase in the experimental group was much less than that in the control group. (Am J Dent 2015;28:224-228).

 

 

Mail: Dr. Jianfeng Zhou, Department of Prosthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun Nandajie, Haidian District, Beijing, 100081, PR China.  E-mail:  dentistzjf@163.com

 

 

Shear bond strength of two adhesives to bovine dentin contaminated

with various astringents

 

Xiaohui Xu, dds,  Quan Chen, phd,  Alexander Lederer,  Christoph Bernau, phd,  Guangyun Lai, dr med dent, Dalia Kaisarly, dr med dent  &  Karl-Heinz Kunzelmann, dr med dent, phd

 

Abstract: Purpose: To investigate the in vitro shear bond strength of two adhesives to bovine dentin contaminated with various astringents. Methods: 120 adult bovine incisors were collected and cut to obtain 240 specimens. The specimens were randomly divided into a self-etch adhesive group (N=120) and a total-etch adhesive group (N=120). Both of the groups were divided into the following six subgroups: the non-contamination group and the contamination groups 25% Al₂(SO₄)₃ (Orbat sensitive), 25% AlCl₃ (Racestyptine), 10% AlCl₃ (Roeko Gingiva Liquid), 15.5% Fe₂(SO₄)₃ (Astringedent) and AlCl₃ Paste (Astringent Retraction Paste, N=20 in each subgroup). Each astringent was applied for 1 minute to the dentin surface before rinsing with water spray for 20 seconds. The respective adhesive was then applied according to the manufacturer’s instructions. Two composite cylinders were shaped with a mold, cured on the dentin surface of each specimen and sheared off after 1 day and 1 week storage. The shear bond strengths (MPa) were recorded and analyzed with ANOVA. Results: In the self-etching adhesive group, all astringents showed negative effects on dentin bonding (P< 0.05). Astringent contamination did not have a negative effect on dentin bonding in the total-etch adhesive group (P> 0.05). (Am J Dent 2015;28:229-234).

 

 

 

Mail: Dr. Xiaohui Xu, Faculty of Dentistry, Department of Operative Dentistry, Ludwig-Maximilians-University, Goethestr. 70, 80336, Munich, Germany.  E-mail: xuxiaohui.cntj@gmail.com

 

 

Short-term clinical performance of zirconia single crowns with different

framework designs: 3-year clinical trial

 

Marco Ferrari, md, dmd, phd,  Roberto Sorrentino, dds, phd,  Maria Crysanti Cagidiaco, md, dmd, phd, Cecilia Goracci, dds, ms, phd,  Alessandro Vichi, dds, phd,  Enrico Gherlone, md, dds  &  Fernando Zarone, md, dds

 

Abstract: Purpose: The present prospective clinical study evaluated the influence of coping design on the fracture resistance of CAD/CAM zirconia single crowns layered with dedicated ceramics. Methods: 56 subjects were provided with 90 zirconia single crowns in posterior regions. Tooth preparations were standardized and the abutment teeth were randomly distributed into three groups, according to three different coping designs (flat design, FD; porcelain-fused-to-metal-like crowns, PFM; anatomically-guided, AG). The zirconia cores were produced using a CAD/CAM software and then were hand-layered with dedicated ceramics. All crowns were cemented with a self-adhesive resin luting agent and the patients were recalled for follow-up visits after 1 month, 6 months, 1, 2 and 3 years of clinical service. The function, esthetics and marginal adaptation of the restorations were evaluated. Statistical analyses were performed to evaluate survival and success of the restorations. Results: Success rates of 100% were reported in Group 2 and Group 3 while the percentage was 80% in Group 1. Three chippings were noticed in Group 1 (FD) and two crowns needed to be replaced after 3 years, resulting in a survival rate of 93.3%. Group 2 and Group 3 had significantly higher 3-year success rates than Group 1 (P< 0.05). Based on the present clinical results, the following conclusions were drawn: the porcelain-fused-to-metal-like and the anatomically-guided frameworks for zirconia single crowns performed better clinically than the flat designed cores in posterior regions after 3 years; standardized tooth preparations achieved even thicknesses of the bilayered restorations; the proper support given to the veneering ceramic by the correct design of the zirconia framework could significantly reduce the risk of chipping during function (Am J Dent 2015;28:235-240).

 

 

 

 

Mail:  Prof. Marco Ferrari, Department of Medical Biotechnologies, School of Dental Medicine, University of Siena, viale Bracci, 53100 Siena, Italy. E-mail: marco.ferrari@unisi.it

 

Temperature changes in bulk-fill resin composite during

photopolymerization

 

Ryan Jin-Young Kim, bds, msd, phd, Young-Ah Yi, dds, msd, phd, Soo-Heang Eo, phd, In-Bog Lee, dds, msd, phd &  Deog-Gyu Seo, dds, msd, phd

 

Abstract: Purpose: To investigate the temperature changes at multiple sites within bulk-fill resin composites and in the pulp chamber during photopolymerization in the tooth cavity. Methods: Class 1 cavities (n = 5) prepared in extracted third molars were filled with SureFil SDR Flow, a newly developed bulk-fill composite. After securing the specimens in a water bath at 36.5°C, eight thermocouples were used to measure the temperature at the bottom center (BC), middle center (MC), top center (TC), bottom edge (BE), middle edge (ME), and top edge (TE) of the restoration; the pulpal aspect of the dentin (PD); and the center of the curing light tip (CL) during photopolymerization. Results: The maximum temperature values (°C) differed among the measurement sites. TC exhibited the greatest temperature increase (72.3 ± 2.4), followed by MC, BC, TE, TE, ME, CL, and BE. The lowest temperature was observed at PD (41.1 ± 1.9). The peak temperatures within the composite were observed during the early stage of light-curing, while CL and PD exhibited the highest temperature at the end stage of light-curing. (Am J Dent 2015;28:241-244).

 

 

Mail:  Dr. Deog-Gyu Seo, Department of Conservative Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, 101 Daehak-ro, Jongno-gu, Seoul, Korea.  E-mail:  dgseo@snu.ac.kr