Dentsply DeTrey GmbH Research Articles

Dislocation Resistance of iRoot SP, a Calcium Silicate–based Sealer, from Radicular Dentine

Introduction The aim of this study was to evaluate the push-out bond strength of iRoot SP (Innovative Bioceramix, Vancouver, Canada) and compare it with that of other widely used root canal sealers. Methods Sixty extracted human maxillary canines were sectioned transversally below the cement-enamel junction to obtain 120 4-mm-thick dentin disks that were randomly divided into four groups ( n = 30) for treatment with one of four different root-canal sealers (iRoot SP, AH Plus [Dentsply DeTrey GmbH, Konstanz, Germany], Sealapex [SybronEndo Corporation, Orange, CA], EndoREZ [Ultradent Inc, South Jordan, UT]). Standardized cavities were prepared to simulate root canals, cavities were filled with sealer material, and push-out bond-strength testing was performed using a universal testing machine. Failure modes were assessed quantitatively under a stereomicroscope and morphologically under a scanning electron microscope. Statistical analysis was performed using one-way analysis of variance and the post hoc Tukey test, with the significance level set at 0.05. Results Bond strengths of iRoot SP and AH Plus were significantly higher than those of Sealapex and EndoREZ. There was no significant difference between the bond strength of iRoot SP and AH Plus ( p = 0.274). Conclusions iRoot SP and AH Plus performed similarly and better than EndoREZ and Sealapex in terms of bond strength.

Influence of Calcium Hydroxide Association on the Physical Properties of AH Plus

Introduction This study evaluated in vitro the radiopacity, setting time, flow, film thickness, solubility, and dimensional changes of AH Plus sealer pure (Dentsply De Trey Gmbh, Konstanz, Germany) and containing 5% and 10% of calcium hydroxide. Methods The study was performed according to the requirements of the ISO 6876:2001 standard and the American National Standards Institute/American Dental Association (ANSI/ADA)'s Specification No. 57. The following tests were performed: setting time, flow, film thickness, dimensional stability, radiopacity, and solubility. Data were analyzed statistically by analysis of variance and the Tukey tests with a significance level of 5%. Results The addition of 5% or 10% calcium hydroxide to AH Plus sealer did not alter significantly the radiopacity or setting time values ( p > 0.05). Adding 10% calcium hydroxide reduced the flow compared with pure AH Plus and AH Plus/5% calcium hydroxide. The addition of 5% and 10% calcium hydroxide increased the solubility and expansion of AH Plus. All materials presented expansion valued above those recommended by the ADA. The addition of calcium hydroxide to the sealer resulted in greater film thickness. Conclusions The addition of 5% calcium hydroxide did not affect most physical properties of AH Plus sealer.

Effects of Three Canal Sealers on Bond Strength of a Fiber Post

Introduction This study evaluated the effects of three different endodontic sealers on the bond strength of a fiber post cemented with adhesive resin cement. Methods Forty-eight extracted maxillary central incisors were prepared with the step-back technique and randomly divided into four groups ( n = 12 for each group): group 1, control group (gutta-percha points only, no sealer); group 2, resin-based sealer (AH plus; Dentsply De Trey GmbH, Konstanz, Germany); group 3, zinc oxide–eugenol-based sealer (Endofill; Produits Dentaires SA, Vevey, Switzerland); and group 4, calcium hydroxide–based sealer (Sealapex; Kerr, Romulus, MI). The roots were obturated with gutta-percha using the cold lateral compaction technique. Fiber posts were cemented into the prepared post spaces with the adhesive resin cement Panavia F 2.0 (Kuraray Medical, Okayama, Japan). A push-out test was performed in a universal machine, and failure modes were observed. Morphologic changes of the root canal dentin surfaces were examined with scanning electron microscopy (SEM). Results One-way analysis of variance revealed that sealers have significant effects on bond strength ( p < 0.05). The control group had the highest mean push-out bond strength. No statistical difference was detected between the eugenol-based sealer group and the resin-based sealer group ( p > 0.05). The root surfaces were covered with the smear layer and debris in all the groups after post space preparation in SEM analysis. However, some of the dentin tubules were partially open in the control and calcium hydroxide–based sealer groups after the application of the resin monomer. Conclusion The results of this study showed that the type of canal sealer and chemomechanical preparation of the root canals affect the bond strength of a fiber post cemented with resin cement.

Microleakage after Thermocycling of Three Self-Etch Adhesives under Resin-Modified Glass-Ionomer Cement Restorations

This study was designed to evaluate microleakage that appeared on Resin-Modified Glass-Ionomer Cement (RMGIC) restorations. Sixty class V cavities (h × w × l = 2 mm × 2 mm × 3 mm) were cut on thirty extracted third molars, which were randomly allocated to three experimental groups. All the buccal cavities were pretreated with polyacrylic acid, whereas the lingual cavities were treated with three one-step Self-Etch adhesives, respectively, Xeno III (Dentsply Detrey GmbH, Konstanz, Germany), iBond exp (Heraeus Kulzer gmbH & Co. KG, Hanau, Germany), and Adper Prompt-L-Pop (3M ESPE AG, Dental products Seefeld, Germany). All cavities were completely filled with RMGIC, teeth were thermocycled for 800 cycles, and leakage was evaluated. Results were expressed as means ± standard deviations (SDs). Microleakage scores were analysed by means of generalized linear mixed models (GLMMs) assuming an ordinal logistic link function. All results were considered to be significant at the 5% critical level (P < .05). The results showed that bonding RMGIC to dentin with a Self-Etch adhesive rather than using polyacrylic acid did not influence microleakage scores (P = .091), except for one tested Self-Etch adhesive, namely, Xeno III (P < .0001). Nevertheless, our results did not show any significant difference between the three tested Self-Etch adhesive systems. In conclusion, the pretreatment of dentin with Self-Etch adhesive system, before RMGIC filling, seems to be an alternative to the conventional Dentin Conditioner for the clinicians as suggested by our results (thermocycling) and others (microtensile tests).

A comparative study of fissure sealants Helioseal Clear Chroma® and Delton® FS+: 3 year results

To evaluate the retention rates of a resin based colour changing fissure sealant (Helioseal Clear Chroma; Ivoclar Vivadent AG Schaan, Liechtenstein) compared with a coloured resin based fluoride fissure sealant (Delton FS(+); Dentsply De Trey GmbH,Konstanz,Germany). The fissure sealants (FS) were placed on all 4 caries-free first permanent molars of 31 children aged 6-9 years, using a half mouth experimental design by a paediatric dentist according to the manufacturers' instructions. A total of 121 FS were placed at baseline. Teeth were evaluated at 3 month intervals for 36 months where a preventive program including topical fluoride application was applied. Retention rates for 36 months showed a differences between Delton FS(+) and Helioseal Clear Chroma that were statistically significant (p<0.05). Delton FS(+) had total retention rate of 30.4% for 36 months compared with Helioseal Clear Chroma at 10.8% for the same evaluation period. Although Delton FS(+) showed significantly better results than Helioseal Clear Chroma for the evaluation periods, there were no statistically significant differences between Delton FS(+) (90.7%) and Helioseal Clear Chroma (80.4%) with respect to caries incidence at 36 months(p>0.05). Delton FS(+) showed a better complete retention rate for occlusal FS at one year. Both FS were aesthetically acceptable and easy to see during application and follow-up periods and gave significant protection from occlusal decay.

Can Radiotherapy Affect the Apical Sealing Ability of Resin-Based Root Canal Sealers?

The authors conducted a study to assess the influence of radiotherapy on the apical sealing ability of one recently introduced resin-based root canal sealer and two sealers that have been in use for several years. The authors divided 90 human maxillary anterior teeth into three groups according to the type of root canal sealer used and, using lateral condensation, obturated the roots with gutta-percha. They randomly divided all roots into two main groups according to the presence or absence of radiotherapy. For the groups that received irradiation, a dose of 60 gray was delivered in fractions of 1.8 Gy per day, five days a week for seven weeks. The authors then performed the centrifuging dye penetration test to determine apical leakage for each specimen. The authors compared the specimens in the groups that received radiotherapy after endodontic treatment with the specimens in the groups that did not undergo radiotherapy after endodontic treatment. They found that mean apical leakage was slightly higher in the radiotherapy groups, but they did not observe any statistical difference between the groups (P > .05). In the groups that did not undergo radiotherapy, the mean apical leakage for the specimens in the MM-Seal (MicroMega, Besançon, France [not marketed in the United States]), AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) and AH 26 (Dentsply DeTrey GmbH) groups was 2.52 +/- 0.42 millimeters, 2.85 +/- 0.52 mm and 3.73 +/- 0.41 mm, respectively. In the groups that underwent radiotherapy, the mean apical leakage for the specimens in the MM-Seal, AH Plus and AH 26 groups was 2.72 +/- 0.55 mm, 2.96 +/- 0.47 mm and 3.93 +/- 0.61 mm, respectively. The apical sealing ability of the resin-based root canal sealers decreased slightly when radiotherapy was administered, although there was no statistically significant difference. Clinicians can safely use a resin-based root canal sealer in patients receiving radiotherapy.

Evaluation of the Radiopacity of New Root Canal Paste/Sealers by Digital Radiography

The aim of the present study was to assess the radiopacity of new polydimethylsiloxane-based root canal filling paste (GuttaFlow; Coltène/Whaledent, Langenau, Germany) and resin-based root canal sealer (Adseal; Meta Biomed Co, Cheongju, Korea) and compare their radiopacity with three currently used root canal sealers (AH Plus [Dentsply DeTrey GmbH, Konstanz, Germany], Epiphany [Pentron, Wallingford, CT], and Diaket [3M ESPE AG, Seefeld, Germany]) by means of direct digital radiography. Six specimens, 5 mm in diameter and 1 mm high, were performed for each material tested. After the material set, radiographs were made by using a digital sensor and a graduated aluminum stepwedge varying in thickness from 1 to 14 mm. These samples were tested according to the international standards to compare their radiodensity to that of the aluminum stepwedge. Data were analyzed using analysis of variance and Tukey tests. The millimeters of aluminum values reported in this study were 10.41, 8.20, 6.50, 4.90, and 3.09 for AH Plus, Epiphany, Diaket, GuttaFlow, and Adseal, respectively. Although the materials evaluated had different radiopacities, all of them showed radiopacity above the minimum recommended by the International Organization for Standardization and the American National Standards/American Dental Association.

Xeno III self-etching adhesive in orthodontic bonding: The next generation

The newer single-step self-etching adhesives that etch, prime, and apply the resin bonding agent simultaneously without rinsing have been increasing in popularity in orthodontic bonding. The purpose of this study was to compare the bond strengths and to evaluate the debonding site (with the adhesive remnant index), when a conventional acid-etch conditioner and a self-etching adhesive system (Xeno III, Dentsply DeTrey GmbH, Konstanz, Germany) were used with either a composite resin adhesive (Transbond XT, 3M Unitek, Monrovia, Calif) or a resin-modified glass ionomer cement (Fuji Ortho LC, GC Corp, Tokyo, Japan). One hundred twenty extracted human premolars were mounted in acrylic resin and randomly assigned to 6 groups of 20 teeth each. Shear-peel bond strength testing was performed after thermocycling (5 degrees C-55 degrees C for 500 times) with a Zwick 1440 compression machine (Zwick, Ulm, Germany). The results showed that the bond strengths achieved with Xeno III were comparable with the traditional methods of either 37% phosphoric acid or 10% polyacrylic acid for both Transbond XT and Fuji Ortho LC. Adhesive remnant index scores showed less adhesive remaining on the tooth surface in the Xeno III/Transbond XT adhesive only (no primer) group. Xeno III can be used to bond orthodontic brackets with the adhesives in this study.

Clinical evaluation of packable and conventional hybrid posterior resin-based composites: Results at 3.5 years

The authors evaluated clinical performances of a packable and a conventional hybrid resin-based composite used with a self-etch adhesive system. Three dentists placed 105 posterior restorations in 65 adults. They placed a packable (SureFil, Dentsply DeTrey GmbH, Konstanz, Germany) and a conventional (Spectrum, Dentsply DeTrey GmbH) resin-based composite using a self-etch resin adhesive system. The authors evaluated the restorations using Ryge modified criteria, photographs and die stone replicas. After 3.5 years, six large SureFil and two Spectrum restorations had failed from bulk fracture and secondary caries, resulting in cumulative survival rates of 81.3 and 92.0 percent, respectively. Failed SureFil restorations generally were larger than the remaining intact restorations. Other ratings were satisfactory, with no significant differences between the two materials for any restoration parameter. Alfa ratings for both materials were approximately 80 percent or greater for marginal discoloration, anatomical form, surface texture and surface staining. Lower percentages of restorations were rated Alfa for color match, marginal integrity and gingival health. No postoperative sensitivity was reported. Net mean occlusal wear (+/- standard deviation) was 28.9 (+/- 32.9) micrometers for SureFil and 33.8 (+/- 29.6) microm for Spectrum restorations; the difference was not statistically significant. When used with a self-etch adhesive, the 3.5-year clinical performances of both composites were similar and satisfactory for the restoration of Class I and moderate-sized Class II cavities. Clinical Implications. The two composites placed in this study have an increased risk of bulk fracture when placed in large intracoronal Class II molar preparations.

The Effect of Bleaching Agents on the Surface Hardness of Tooth Colored Restorative Materials

The aim of this study was to evaluate the effect of at-home (Opalesence/Dr. kit 15%, Ultradent, Products, Inc. South Jordan, UT, USA) and in-office (Superoxol 35%, Sultan Chemists, Inc., Englewood, NJ, USA) bleaching on the surface hardness of the following tooth colored restorative materials: composite resin, Point-4 (P4), Kerr Corporation, Orange, CA, USA; ormocer, Admira (AD),VOCO, Germany; compomer Dyract AP (DY), Dentsply DeTrey GmbH, Germany; and resin modified glass ionomer cement, Fuji II LC (FL), GC Corporation, Japan. Sixty specimens were prepared; 15 specimens of each material (each group n = 5, control after 15 days, at-home and in-office). All specimens were stored in distilled water at room temperature for 24 hrs before testing. A universal testing machine (Micromet 2100 series micro hardness testers) was used for testing Vicker's surface hardness for the three groups for every tested material. All results were statistically analyzed with one way analysis of variance (ANOVA), Post hoc Tukey HSD tests (P < 0.05), and percentage changes for Tukey. All the tested materials showed an increase in Vicker's surface hardness between base line (24 hrs) and the control group after 15 days storage in distilled water except DY which showed a decrease in surface hardness. All tested materials showed a decrease in surface hardness from control group after 15 days and both at-home and in-office bleaching agents except DY which showed increased values. At-home as well as in-office bleaching agents have a softening effect on some tooth colored restorative material, and the patient must be aware before using them.

Effect of Bleaching and Repolishing Procedures on Coffee and Tea Stain Removal from Three Anterior Composite Veneering Materials

Discolored teeth can be treated with resin veneers, but their color changes when confronted with staining solutions. Polishing procedures can provide a remedy for highly stained composites, but they tend to remove some materials as well. However, bleaching procedures are an effective, nondestructive method for solving the problem. The aim of this study was to compare the color change of three veneer composites exposed to staining solutions and to evaluate the effectiveness of a 15% hydrogen peroxide bleaching agent and three polishing systems to remove the stain. Forty-five disks (12 x 2 mm) each of Clearfil ST (Kuraray Co. Ltd., Osaka, Japan), Esthet-X (Dentsply/Caulk, Milford DE, USA), and Filtek A110 (3M ESPE, St. Paul, MN, USA) were prepared. The specimens were polished with Sof-Lex (3M ESPE), Enhance (Dentsply/Caulk), or PoGo (Dentsply/Caulk). Five specimens for each material-polishing system combination were immersed in coffee (Nescafe Classic, Nestle SA, Vevey, Switzerland) or tea (Earl Grey, Lipton, Blackfriars-London, England) for 7 days. The remaining disks were stored in water. Color measurements were made with a spectrophotometer (X-Rite Seroice SP78, Loaner, Köln, Germany) at baseline; after 1, 3, 5, and 7 days; and after bleaching and repolishing. After 1 week, one side of the specimens was bleached with Illuminé-office (Dentsply De Trey GmbH, Konstanz, Germany) for 1 hour, and the other side was repolished for 30 seconds. All comparisons of color change for the polishing systems, times, and staining solutions were subjected to repeated measurements of analysis of variance. Paired t-test was used to examine whether significant color differences (deltaE*) occurred during immersion at the specified time intervals (p < or = .05). Filtek A110 was the least stained resin composite. Its color remained under a deltaE* value of 2 during the study. Clearfil ST exhibited the most color change after 1 week. All specimens polished with Enhance showed less staining, whereas those polished with the Sof-Lex system demonstrated the most color change. Water did not cause a variance in the deltaE*. There was no difference in the staining potential of coffee and tea. Bleaching and repolishing were effective in removing the stains. The resin composites tested reversed nearly to baseline color with the bleaching and to less than values at 1 day of staining with repolishing. The coffee and tea brands tested stained the composites used in this study equally. In-office bleaching was found to be more effective than repolishing in the restitution of the color. The results of this study suggest that the discoloration of resin veneers can be partially removed by in-office bleaching and repolishing procedures.

Clinical evaluation of packable and conventional hybrid resin-based composites for posterior restorations in permanent teeth: Results at 12 months

Packable resin-based composites and simplified resin bonding systems are marketed to offer many advantages over conventional posterior hybrid composites and total-etch bonding systems. The authors conducted a study to evaluate the initial clinical performances of a packable and a conventional hybrid resin-based composite used with a simplified bonding system. A total of 57 Class I and 45 Class II restorations were placed in the permanent teeth of 65 adult patients. The carious lesions were restored with either packable resin-based composite (SureFil, Dentsply DeTrey GmbH, Konstanz, Germany) or conventional hybrid resin-based composite (SpectrumTPH, Dentsply DeTrey GmbH), using a resin adhesive (Non-Rinse Conditioner and Prime & Bond NT, both manufactured by Dentsply DeTrey GmbH). The authors evaluated the restorations using U.S. Public Health Service-Ryge modified criteria (in which Alfa is the highest rating) and by using color transparencies and die stone replicas. Three SureFil restorations failed before their baseline evaluation. There were no failures among the 78 SpectrumTPH restorations evaluated at 12 months. For both resin-based composites, Alfa ratings were 90 percent or higher for marginal discoloration, anatomical form, surface texture and surface staining. Lower percentages of restorations were rated Alfa for color match, marginal integrity and gingival health. Occasional mild postoperative sensitivity was reported for four SureFil restorations and one SpectrumTPH restoration. The mean occlusal wear rate was 38 micrometers for the larger SureFil restorations and 25 microm for the smaller SpectrumTPH restorations. The 12-month clinical performances of the two restorative materials were satisfactory and not significantly different for each of the parameters evaluated. A packable and a conventional hybrid resin-based composite placed with a simplified bonding system in posterior permanent teeth showed satisfactory and similar results after 12 months.

Two-year clinical evaluation of a packable resin-based composite

Packable resin-based composites were introduced in 1998, but few clinical studies have been conducted to evaluate them. The authors conducted a clinical study to determine the two-year performance of SureFil (Dentsply DeTrey GmbH, Konstanz, Germany) packable posterior resin-based composite in Class I and II restorations. An operator (L.S.T.) restored 55 cavities in 36 patients (16 Class I restorations and 39 Class II restorations). After cavity preparation, she etched the enamel with 34 percent phosphoric acid, applied Prime & Bond NT (Dentsply DeTrey GmbH) to dentin and etched enamel for 20 seconds and then cured it for 20 seconds. She restored the cavity using 3- to 5-millimeter increments of SureFil. Independent examiners assessed the restorations after placement and at six months, one year and two years for color matching, marginal discoloration, marginal adaptation, secondary caries, surface texture, anatomical form and postoperative sensitivity, using the Ryge criteria. The authors assessed the changes in the parameters during the two-year period using a software program with Friedman test analysis with a Bonferroni adjustment at significant level of P = .05. At baseline, 31 restorations were graded as Bravo for color match. At the six-month and one-year recall periods (n = 55), 53 restorations remained unchanged. Two restorations from the same patient fell out after one month. After two years (n = 50), there were five Bravos for surface staining and three for marginal adaptation (P < .05). After two years of clinical service, SureFil packable resin-based composite had a success rate of 96 percent, and the authors considered it successful in Class I and II restorations. SureFil packable resin-based composite can be successful in clinical situations with limited-sized cavities and proper application of restorative techniques.

Relationship between the balance of protrusive occlusion and the inclination of the condylar guidance for complete dentures. : Hong Liu and Sun Lian (1985) Chin. J. Stomatol 20, 75–77.

The aim of the present study was to assess the radiopacity of new polydimethylsiloxane-based root canal filling paste (GuttaFlow; Coltène/Whaledent, Langenau, Germany) and resin-based root canal sealer (Adseal; Meta Biomed Co, Cheongju, Korea) and compare their radiopacity with three currently used root canal sealers (AH Plus [Dentsply DeTrey GmbH, Konstanz, Germany], Epiphany [Pentron, Wallingford, CT], and Diaket [3M ESPE AG, Seefeld, Germany]) by means of direct digital radiography. Six specimens, 5 mm in diameter and 1 mm high, were performed for each material tested. After the material set, radiographs were made by using a digital sensor and a graduated aluminum stepwedge varying in thickness from 1 to 14 mm. These samples were tested according to the international standards to compare their radiodensity to that of the aluminum stepwedge. Data were analyzed using analysis of variance and Tukey tests. The millimeters of aluminum values reported in this study were 10.41, 8.20, 6.50, 4.90, and 3.09 for AH Plus, Epiphany, Diaket, GuttaFlow, and Adseal, respectively. Although the materials evaluated had different radiopacities, all of them showed radiopacity above the minimum recommended by the International Organization for Standardization and the American National Standards/American Dental Association.