on resin composite restorations in primary teeth
Márcia Gomes, dds, ms, Renata Franzon, dds, ms, Carla Moreira Pitoni, dds, ms, phd,
Juliana Sarmento Barata, dds, ms, phd, Franklin GarcÍa-Godoy, dds, ms, phd
& Fernando Borba de Araujo, dds, ms, phd
Abstract: Purpose: To clinically evaluate the status of caries lesions adjacent to restorations (AdjCL) in primary molars, and its relationship to the child’s carious activity and marginal restoration integrity. Methods: Three independent examiners (trained, calibrated and blinded) evaluated 64 randomly selected restorations (occlusal and occluso-proximal) by the AdjCL status (kappa= 0.844), the restoration marginal integrity (kappa= 1) and the radiographic presence of lesions in the occlusal restoration margins (kappa=1). One of the examiners also evaluated the child’s carious activity (kappa=1). The variables were related to the outcome through Chi-square and Fisher’s Exact analysis (α= 5%). Results: A prevalence of 40.63% AdjCL (88.46% inactive) was seen, with no significant association to the child’s carious activity (P= 0.23). The association of the absence of AdjCL and the presence of marginal integrity was statistically significant (P= 0.013). Also, the presence of AdjCL occurred especially around older restorations (P= 0.044). (Am J Dent 2012;25:255-261).
Mail: Prof. Fernando Borba de Araujo, Rua Ramiro Barcelos, 2492, Faculdade de Odontologia – UFRGS, Odontopediatria, Bom Fim, Porto Alegre – Rio Grande do Sul, CEP: 90035-003, Brazil. E-mail: email@example.com
of dentin hypersensitivity: A 4-week clinical study
Jeffery L. Milleman, dds, mpa, Kimberly R. Milleman, rdh, bsed, ms, Courtney E. Clark, bs, cba, rac, Kimberly A. Mongiello, ms, Thomas C. Simonton, ms & Howard M. Proskin, phd
Abstract: Purpose: The primary objective of this study was to compare the effectiveness of NUPRO Sensodyne Prophylaxis Paste with NovaMin, with and without fluoride, to a standard prophylaxis paste without fluoride (control) in reducing dentin hypersensitivity immediately after a single application following dental scaling and root planing. The secondary objective was to compare the duration of sensitivity relief up to 28 days after a single application of the NUPRO pastes with NovaMin compared to the control paste. Methods: This was a randomized, single-center, controlled, three-treatment, parallel-group study conducted at Salus Research in Fort Wayne, Indiana. Male and female subjects who met all inclusion/exclusion criteria and had two non-adjacent sensitive teeth based on tactile (Yeaple probe) and air blast assessments, were enrolled in the study. At baseline, tactile and air blast stimuli were administered and subjects were stratified according to their baseline air blast (Schiff) scores into one of three treatment groups: Group A (NovaMin without fluoride), Group B (NovaMin with fluoride) or Group C (NUPRO classic prophylaxis paste without fluoride). Subjects were then assessed post-treatment and at a 28-day follow-up using tactile and air blast methods. Results: A total of 139 patients completed the study. Subjects having received the NovaMin containing prophylaxis pastes (Groups A and B) showed statistically lower (ANOVA, P< 0.05) dentin hypersensitivity compared to the control group immediately after the prophylaxis procedure. Group A tactile improvements were 86% immediate, and 88% after 28 days; air blast improvements were 49% immediate, and 50% after 28 days. Group B tactile improvements were 67% immediate, and 65% after 28 days; air blast improvements were 43% immediate, and 34% after 28 days. Group C experienced little improvement in tactile and air blast scores, 9% and 4% respectively, immediately following treatment, and 10% and 1% respectively after 28 days. At both time points, the reduction in sensitivity was meaningful and significantly better than in the group receiving a standard prophylaxis paste as the comparator (P< 0.05). Both NovaMin pastes were effective and there was no statistical difference between the pastes with and without fluoride. There were no adverse events reported during the course of this study. (Am J Dent 2012;25:262-268).
Mail: Ms. Courtney E. Clark, Clinical and Regulatory Affairs Department, Dentsply Professional Division, 1301 Smile Way, York, PA 17404, USA. E-mail: firstname.lastname@example.org
to zirconia ceramic after different pre-treatments
Alessio Casucci, dds, msc, Cecilia Goracci, dds, msc, phd, Nicoletta Chieffi, dds, msc, phd,
Francesca Monticelli, dds, msc, phd, Agostino Giovannetti, dds, Jelena Juloski, dds
& Marco Ferrari, md, dds, phd
Abstract: Purpose: To evaluate the influence of different surface treatments and metal primer application on bond strength of zirconia ceramic to a self-adhesive resin cement. Methods: 40 cylinder-shaped (Ø 12 x 5.25 mm high) of zirconia ceramic (Aadva Zirconia) were randomly divided into four groups (n= 10), based on the surface treatment to be performed: (1) Sandblasting with 125 µm Al2O3 particles (S) (positive control); (2) Selective infiltration etching (SIE); (3) Experimental heated etching solution applied for 30 minutes (ST); (4) No treatment (C). Half of the zirconia specimens of each group received the application of Metal Primer II. Eight disks for each group were luted using a self-adhesive resin cement (G-Cem Automix) to composite overlays (Paradigm MZ100). After 24-hour storage (37°C, 100% RH) bonded specimens were cut into microtensile sticks and loaded in tension until failure. Data were analyzed with two-way ANOVA and Games-Howell (P< 0.05). Failure mode distribution was recorded and scanning electron microscopy (SEM) was used to examine the fractured microbars. The remaining cylinders of each group (n= 2) were used for SEM surface analysis. Results: Both surface treatments and Metal Primer II application improved bond strength values (P< 0.05). When Metal Primer II was not applied ST treatment achieved highest bond strength values (22.17 ± 10.37 MPa). Sandblasting in combination with Metal Primer II enhanced bond strength values compared to the other groups (23.46 ± 11.19 MPa). (Am J Dent 2012;25;269-275).
Mail: Prof. Marco Ferrari, Department of Fixed Prosthodontics and Dental Materials, University of Siena, Policlinico “Le Scotte”, Viale Bracci 1, 53100, Siena, Italy. E-mail: email@example.com
when included in a bonding system
Benjamin Hechler, bs, Xiaomei Yao, phd & Yong Wang, phd
Abstract: Purpose: To determine the effect of proanthocyanidins (PA) incorporation into a bonding system on dentin/adhesive bond stability following long-term storage in buffer and collagenase. Methods: Human dentin surfaces were bonded with no PA (0-PA), PA incorporated in the primer (PA-primer), or PA incorporated in the adhesive (PA-adhesive), and composite build-ups were created. Following sectioning into beams, bonded specimens were stored in buffer or collagenase for 0, 1, 4, 26, or 52 weeks before being tested for microtensile bond strength (µTBS). ANOVA and Tukey’s HSD post-hoc were performed. Fractured surfaces were viewed with scanning electron microscopy (SEM). Results: Both bonding system and storage time but not storage medium significantly affected µTBS. Initially, 0-PA and PA-primer were superior to PA-adhesive, and after 1 week both PA groups were inferior to 0-PA. However, after 4 weeks PA-adhesive had significantly increased and 0-PA significantly decreased such that all three groups were equal. Thereafter, both PA-primer/adhesive groups trended with an increase (the 0-PA group remaining consistent) such that at 52 weeks PA-primer samples were significantly stronger (P< 0.001) or nearly so (P= 0.08) when compared to 0-PA samples. SEM revealed that initial fractures tended to occur at the middle/bottom of the hybrid layer for 0-PA and PA-primer groups but at the top of the hybrid layer/in the adhesive for PA-adhesive. After 4 weeks, however, all groups fractured similarly at the middle/bottom of the hybrid layer. (Am J Dent 2012;25:276-280).
Mail: Dr. Yong Wang, University of Missouri-Kansas City, School of Dentistry, 650 E. 25th Street, Kansas City, MO 64108, USA. E-mail: firstname.lastname@example.org
paste on the microtensile bond strength of self-etching dental adhesives
to human dentin
Yake Wang, mds, Siying Liu, mds, Dandan Pei, phd, Xijin Du, mds, Xiaobai Ouyang, phd
& Cui Huang, ms,mds,phd
Abstract: Purpose: To evaluate in the laboratory the effect of an 8.0% arginine and calcium carbonate desensitizing paste in occluding open dentin tubules and examine the effect of bonding between the adhesive agents and dentin after being treated with the desensitizing paste. Methods: Two self-etching adhesives were used. Intact human premolars extracted for orthodontic reasons were used within 3 months of extraction. The occlusal enamel was removed and dentin slices were polished. The dentin tubules were opened by etching with a 1% citric acid solution for 20 seconds to simulate a postoperative sensitivity model. Then the specimens were randomly assigned into five groups. Group A: specimens without any treatment (control). Group B: specimens were polished with a slurry (SiO2) for 30 seconds. Groups C, D and E: 8.0% arginine and calcium carbonate desensitizing paste was applied. Specimens in Group C were polished for 3 seconds, and then repeated for another 3 seconds for a total of 6 seconds, according to the manufacturer’s instructions: specimens in Group D were polished twice for 9 seconds for a total of 18 seconds; and specimens in Group E were treated for an extended time of 30 seconds. Each group was randomly divided into two sub-groups in order to evaluate the effect on two different adhesive agents. A one-step self-etching adhesive agent (G-Bond) and a two-step self-etching adhesive agent (Fl-Bond II) were applied following the manufacturers’ instructions. Then microtensile bond strengths of the 10 groups were tested. SEM was used to evaluate the laboratory effect of the desensitizing paste in occluding open dentin tubules. Statistical analysis was carried out using SPSS version 16.0. Results: The SEM observations showed that the 8.0% arginine and calcium carbonate desensitizing paste could occlude the dentin tubules effectively, and thus may have potential benefits in preventing postoperative sensitivity based on the hydrodynamic theory. An extended application time of 18 or 30 seconds showed no adverse effect of the desensitizing paste on the bonding performance to dentin when using self-etching adhesives containing functional monomers such as 4-MET like G-Bond. (Am J Dent 2012;25:281-286).
Mail: Dr. Cui Huang, The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China. E-mail: email@example.com
versus a new sonic power toothbrush in reducing gingivitis and plaque
Malgorzata Klukowska, dds, phd, Julie M. Grender, phd, C. Ram Goyal, dds, Christian Mandl, phd & Aaron R. Biesbrock, dmd, phd, msc
Abstract: Purpose: To evaluate the efficacy of an advanced rotation/oscillation power toothbrush (Oral-B Triumph with SmartGuide) relative to a new sonic power toothbrush (Sonicare DiamondClean) in the reduction of gingivitis and plaque over a period of 12 weeks. Methods: This was a single-center, open-label, examiner-blind, two-treatment, parallel group, randomized study in which subjects brushed with their assigned toothbrush and a marketed dentifrice for 2 minutes twice daily at home for 12 weeks. Gingivitis and plaque were evaluated at baseline, Week 6 and Week 12 using the Modified Gingival Index (MGI), Number of Bleeding Sites, and Rustogi Modification of the Navy Plaque Index (RMNPI). Safety was also assessed at every visit. At the end of the study, subjects completed a consumer questionnaire to evaluate their brushing experience. Results: In total, 130 subjects were randomized to treatment and completed the study (65 per group). The rotation/oscillation group had higher gingivitis reductions from baseline at Weeks 6 and 12 by 31.9% and 32.3%, respectively, for MGI and by 43.4% and 34.9%, respectively, for number of bleeding sites than the sonic group. Group differences at both Weeks 6 and 12 were highly significant (P< 0.001) for both MGI and number of bleeding sites. The rotation/oscillation group had higher RMNPI plaque reductions from baseline at Weeks 6 and 12 by 15.8% and 19.3%, respectively, for whole mouth; by 24.1% and 30.4% at the gumline; and by 22.9% and 24.4% in the approximal regions, than the sonic group. Comparisons between groups at Week 12 were highly significant (P≤ 0.002) for all three mouth areas; group differences at Week 6 were significant (P< 0.05) for whole mouth and approximal RMNPI. Analysis of the questionnaire data showed that subjects using the rotation/oscillation brush rated it higher for several key attributes than subjects in the sonic group. There were no safety concerns with either brush. (Am J Dent 2012;25:287-292).
Mail: Dr. Malgorzata Klukowska, Procter & Gamble Health Care Research Center, 8700 Mason-Montgomery Road, Mason, OH, 45040, USA. E-mail: firstname.lastname@example.org
on dentin hypersensitivity
Jugal Vora, bds, Deepak Mehta, bds, mds, Naganath Meena, bds, mds, Galagali Sushma, bds, mds,
Werner J. Finger, dr med dent, phd & Masafumi Kanehira, dmd, phd
Abstract: Purpose: To evaluate the efficacy of two commercial desensitizing agents in subjects with moderate to severe dentin hypersensitivity for a period of 6 months and to compare the results with topical application of water as negative control. Methods: BisBlock (BIS; oxalate) and Gluma Desensitizer PowerGel (GLU; glutaraldehyde/HEMA) were tested. 50 subjects, average age 32.4 years, with at least one cervical hypersensitive incisor, canine or premolar tooth area and pre-operative pain score ≥ 6 on VAS from 0 to 10 in each of three quadrants were included. Prior to application of the desensitizing agents or placebo (PLA; water) the sensitive areas were cleaned with prophy paste. Desensitizers were applied according to manufacturers’ instructions, the placebo was left for 60 seconds dwell, rinsed off and dried. Pain scores were determined using both evaporative and tactile stimuli immediately after treatment, after 1 day, 1 week, 1, 3 and 6 months. Statistical analyses of the findings were performed using ANOVA and pot-hoc tests with a significance set at P≤ 0.05. Results: All subjects completed the trial. Both the two desensitizing agents and placebo showed significant reduction in sensitivity at baseline and throughout the 6-month evaluation. The effects of the three treatments were significantly different. Pain reduction with GLU was consistently highest, followed by PLA that was significantly greater than BIS. VAS scores for the evaporative stimulus were moderately, but significantly lower than for tactile stimulation. (Am J Dent 2012;25:293-298).
Mail: Prof. Werner J. Finger, Division of Operative Dentistry, Department of Restorative Dentistry, Tohoku University Graduate School of Dentistry, 4-1 Seiryo machi, Aoba-ku, Sendai 980-8575, Japan. E-mail: email@example.com
enamel treated with several concentrations of ammonium hexafluorosilicate
Toshiyuki Suge, dds, phd, Kunio Ishikawa, phd & Takashi Matsuo, dds, phd
Abstract: Purpose: To evaluate the effects of changing concentrations of ammonium hexafluorosilicate [SiF: (NH4)2SiF6] solution on the crystallinity of hydroxyapatite powder (HAP) and structure of human enamel in order to overcome the tooth discoloration caused by diamine silver fluoride [AgF: (NH3)2AgF] application. Methods: HAP was treated with several concentrations of SiF solution (from 10 to 19,400 ppm) for 5 minutes. The crystallinity of the HAP before and after SiF treatment was then measured by powder X-ray diffraction (XRD) analysis. The angular width (β) of the 002 diffraction peak was measured at 1/2 the height of the maximum intensity. Also, enamel specimens were prepared from a human extracted tooth. Several concentrations of SiF solution were applied to polished or phosphoric acid etched enamel specimens. The enamel surface was then observed using scanning electron microscopy (SEM). Results: XRD peaks became sharper after SiF treatment indicating that the crystallinity of apatite powder was increased. The 1/β value was increased from 2.8 ± 0.1 to 4.3 ± 0.1 after treatment with 1,000 ppm SiF solution. The amount of CaF2 formed in HAP was gradually increased with increasing concentrations of SiF solution. The XRD pattern was consistent with CaF2 in case of over 9,000 ppm SiF solution. SEM photographs demonstrated that exposed enamel rods with acid etching were filled with CaF2-like precipitate after SiF treatment regardless of the concentration of SiF solution. (Am J Dent 2012:25:299-302).
Mail: Dr. Toshiyuki Suge, Department of Conservative Dentistry, Institute of Health Biosciences, University of Tokushima Graduate School, 3-18-15 Kuramoto, Tokushima 770-8504, Japan. E-mail: firstname.lastname@example.org
Nehal Waheeb, bds, Nick Silikas, bsc (hons), mphil, phd & David Watts, bsc, phd, dsc
Abstract: Purpose: To determine the effect of finishing and polishing time on the surface gloss of various resin-composites before and after simulated toothbrushing. Methods: Eight representative resin-composites (Ceram X mono, Ceram X duo, Tetric EvoCeram, Venus Diamond, Estelite∑ Quick, Esthet.X HD, Filtek Supreme XT and Spectrum TPH) were used to prepare 80 disc-shaped (12 mm x 2 mm) specimens. The two step system Venus Supra was used for polishing the specimens for 3 minutes (Group A) and 10 minutes (Group B). All specimens were subjected to 16,000 cycles of simulated toothbrushing. The surface gloss was measured after polishing and after brushing using the gloss meter. Results were evaluated using one way ANOVA, two ways ANOVA and Dennett’s post hoc test (P= 0.05). Results: Group B (10-minute polishing) resulted in higher gloss values (GV) for all specimens compared to Group A (3 minutes). Also Group B showed better gloss retention compared to Group A after simulated toothbrushing. In each group, there was a significant difference between the polished composite resins (P< 0.05). For all specimens there was a decrease in gloss after the simulated toothbrushing. (Am J Dent 2012;25:303-306).
Mail: Nehal Waheeb, 1 Colville Grove, Sale, Cheshire, United Kingdom. E-mail: email@example.com
root canal dentin
Mohamed F. Ayad, bds, mscd, phd, Lamiaa A. Ibrahim, bds, ms, phd & Robert G. Rashid, dds, mas
Abstract: Purpose: To compare the laboratory bond strengths of three different types of fiber-reinforced composite dowel systems in three different locations of prepared root canal dentin. Methods: 60 human extracted intact upper central incisors were selected. The coronal aspect of each tooth was removed, and the remaining root received endodontic therapy. The roots were divided into three experimental groups (n=20). Roots were restored with one of the following dowel systems according to the manufacturers’ instructions: carbon fiber (C-Posts), quartz (Aestheti-Plus), glass fiber (FibreKor). A single bond adhesive (OptiBond Solo Plus) was applied to the walls of the dowel spaces, excess carefully removed with paper points, and then light cured for 10 seconds. A dual-polymerizing resin luting agent (Variolink II) was mixed and then placed in the dowel spaces using a lentulo spiral instrument. The roots were placed in light-protected cylinders; then the light source was placed directly on the flat cervical tooth surfaces and the cement was polymerized. Specimens were stored in light-proof boxes for 24 hours. Each root was cut horizontally, and three 1 mm-thick root segments (one apical, one middle, and one cervical) were prepared. Using a push-out test, the bond strength between dowel and dentin was measured using a universal testing machine. The data were analyzed with 2-way analysis of variance and Tukey’s Honestly Significant Difference (HSD) test (α= 0 .05). Results: Dowel type and regional root canal dentin resulted in significant differences for push-out bond strength (P< 0.001). Glass fiber dowels (FibreKor) had significantly higher mean bond strength values (SD) for all dowel space regions: coronal (13.6 [1.5] MPa), middle (10.8 [1.8] MPa), and apical (8.9 [1.1] MPa). The carbon fiber dowels (C-Posts) had significantly lower bond strength values in all dowel space regions: coronal [8.6 (1.1) MPa], middle (4.7 [1.0] MPa), and apical (4.1 [1.1] MPa). Quartz dowels (Aestheti-Plus) had intermediate bond strength values: coronal (10.9 [1.1] MPa), middle (9.6[1.1] MPa), and apical (7.7 [1.1] MPa). Also, there were differences in bond strength between regional root canal dentin, with a reduction in values from the coronal to middle and apical thirds for all experimental groups (P < 0.001). (Am J Dent 2012;25:307-312).
Mail: Dr. Mohamed F. Ayad, PO Box 80209, Jeddah 21589, Saudi Arabia. E-mail: firstname.lastname@example.org