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Gandolfi MG, Taddei P, Siboni F, Modena E, Ginebra MP, Prati C. Fluoride-containing nanoporous calcium-silicate MTA cements for endodontics and oral surgery: early fluorapatite formation in a phosphate-containing solution. International Endodontic Journal, 44, 938–949, 2011. Aim To test the chemical–physical properties and apatite-forming ability of experimental fluoride-doped calcium silicate cements designed to create novel bioactive materials for use in endodontics and oral surgery. Methodology A thermally treated calcium silicate cement (wTC) containing CaCl2 5%wt was modified by adding NaF 1%wt (FTC) or 10%wt (F10TC). Cements were analysed by environmental scanning electron microscopy with energy-dispersive X-ray analysis, IR and micro-Raman spectroscopy in wet conditions immediately after preparation or after ageing in a phosphate-containing solution (Dulbecco’s phosphatebuffered saline). Calcium and fluoride release and pH of the storage solution were measured. The results obtained were analysed statistically (Tukey’s HSD test and two-way anova). Results The formation of calcium phosphate precipitates (spherulites) was observed on the surface of 24 h-aged cements and the formation of a thick bone-like B-type carbonated apatite layer (biocoating) on 28 day-aged cements. The rate of apatite formation was FTC > F10TC > wTC. Fluorapatite was detected on FTC and F10TC after 1 day of ageing, with a higher fluoride content on F10TC. All the cements released calcium ions. At 5 and 24 h, the wTC had the significantly highest calcium release (P < 0.001) that decreased significantly over the storage time. At 3–28 days, FTC and F10TC had significantly higher calcium release than wTC (P < 0.05). The F10TC had the significantly highest fluoride release at all times (P < 0.01) that decreased significantly over storage time. No significant differences were observed between FTC and wTC. All the cements had a strong alkalinizing activity (OH) release) that remained after 28 days of storage. Conclusions The addition of sodium fluoride accelerated apatite formation on calcium silicate cements. Fluoride-doped calcium silicate cements had higher bioactivity and earlier formation of fluorapatite. Sodium fluoride may be introduced in the formulation of mineral trioxide aggregate cements to enhance their biological behaviour. F-doped calcium silicate cements are promising bone cements for clinical endodontic use.

This study aimed to characterize the chemical properties and bioactivity of an endodontic sealer (GuttaFlow Bioseal) based on polydimethylsiloxane (PDMS) and containing a calcium bioglass as a doping agent. Commercial PDMS-based cement free from calcium bioglass (GuttaFlow 2 and RoekoSeal) were characterized for comparison as well as GuttaFlow 2 doped with dicalcium phosphate dihydrate, hydroxyapatite, or a tricalcium silicate-based cement. IR and Raman analyses were performed on fresh materials as well as after aging tests in Hank’s Balanced Salt Solution (28 d, 37 °C). Under these conditions, the strengthening of the 970 cm−1 Raman band and the appearance of the IR components at 1455–1414, 1015, 868, and 600–559 cm−1 revealed the deposition of B-type carbonated apatite. The Raman I970/I638 and IR A1010/A1258 ratios (markers of apatite-forming ability) showed that bioactivity decreased along with the series: GuttaFlow Bioseal > GuttaFlow 2 > RoekoSeal. The PDMS matrix played a relevant role in bioactivity; in GuttaFlow 2, the crosslinking degree was favorable for Ca2+ adsorption/complexation and the formation of a thin calcium phosphate layer. In the less crosslinked RoekoSeal, such processes did not occur. The doped cements showed bioactivity higher than GuttaFlow 2, suggesting that the particles of the mineralizing agents are spontaneously exposed on the cement surface, although the hydrophobicity of the PDMS matrix slowed down apatite deposition. Relevant properties in the endodontic practice (i.e., setting time, radiopacity, apatite-forming ability) were related to material composition and the crosslinking degree.

Purpose:This 3-year study aimed to evaluate hard and soft tissue modification around a two-piece implant characterized by a transmucosal hyperbolic neck in healthy consecutive patients with a need for single-tooth replacement. Materials and Methods: Two-piece implants (n = 66) were placed with a flapless technique in 56 patients (27 men; 29 women; mean age 55 ± 9 years): 16 immediately after root extraction (immediate group), 20 after 8 to 12 weeks (early group), and 30 after 10 or more months (delayed group). The transmucosal hyperbolic neck was exposed 1 to 1.5 mm above gingival level. Customized abutments were positioned 3 months later with the implant-abutment connection located approximately 1 to 1.5 mm above soft tissue level. Provisional cemented resin crowns were designed with the finishing line at the hyperbolic neck and then positioned to avoid excessive compression of soft tissue, to guide gingival contours. Twenty days later, a definitive metal-ceramic crown was cemented. In all patients, the gingival biotype (thin or thick) was also evaluated. The primary outcomes were as follows: 36-month implant survival rate, peri-implant marginal bone level (MBL, in mm) changes observed in single-blind on radiographs at 1, 3, 6, 12, 24, and 36 months (T1, T3, T6, T12, T24, and T36), and pink esthetic score (PES) at T6, T12, and T36 to analyze soft tissue adaptation after loading and crown application. The secondary outcomes were as follows: plaque score and bleeding on probing (BOP). Linear regression models and multilevel mixed logistic regression were used to detect any statistical difference of MBL according to operative parameters. Kruskal-Wallis one-way analysis of variance (ANOVA) on ranks was performed to assess statistical differences of PES at T6, T12, and T36. Results: The survival rate was 100%. The dropout rate was 1.79%. No infections, mucositis, or peri-implantitis were reported. Implants placed in thick-biotype tissues showed a statistically different lower bone loss at 36 months with respect to the thin biotype (P

Purpose: To examine the microscopic surface features, chemical composition, and thermodynamic profile of seven endodontic sealers (AH Plus, Adseal, MTA-Fillapex, RoekoSeal, GuttaFlow 2, GuttaFlow BioSeal, and EndoRez) exposed to high-temperature changes using an endodontic obturation device. Methods: The thermal properties were examined using scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Then, six disc-shaped specimens of each sealer were prepared and divided into two groups – a room temperature group and a heat exposure group – for analysis of surface and chemical changes using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Results: DSC analysis showed that AH Plus had the highest exothermal signal (122.9°C), while TGA analysis showed that MTA-Fillapex was most affected by increased temperature (32.4% mass loss at 230ºC). SEM analysis showed that while AH Plus and GuttaFlow BioSeal maintained their surface integrity after heat exposure, the EDS profiles demonstrated changes in the chemical composition of the sealers after heat exposure for 5 s. High-temperature exposure had a negative impact on the properties of five of the sealers (Adseal, MTA-Fillapex, RoekoSeal, GuttaFlow 2, and EndoRez). Conclusion: AH Plus and GuttaFlow BioSeal showed minimal changes upon high-temperature exposure, suggesting their suitability for thermal endodontic obturation techniques. Universidad de Costa Rica/[816-B8-279]/UCR/Costa Rica UCR::Vicerrectoría de Docencia::Salud::Facultad de Odontología

Aim: This 60-month prospective study aimed to evaluate tooth survival and healing rates after root canal treatment in patients taking bisphosphonates (BPs). Secondary outcomes were complications and clinical variables observed during and after treatment. Methods: Root canal treatment was performed using manual K-file canal instrumentation and a carrier-based filling technique with an epoxy resin-based sealer. Teeth without adequate root/crown integrity were restored by trained operators at the tissue level (TL group) to prevent occlusal/mechanical stress and to enable periapical lesion healing without the risk of root fracture. Other teeth were restored with normal occlusal contacts (OC group). Healthy patients who had undergone one or more root canal treatments of the same type constituted the control group. The relationships of the following variables to survival and health status were examined (chi-squared test and multivariate analysis, P=0.05): age, gender, smoking habit, tooth location, treatment type, BPs treatment, BPs exposure, initial periapical index (PAI) and occlusal restoration. Survival curves were constructed using Kaplan–Meier analysis, with extraction serving as the end-point. Results: In total, 65 patients with 109 root canal-treated teeth who were taking BPs were included. At 60months, data from 57 patients (52F, 5M; median age 65.7±8.6years) who had undergone 96 root canal treatments were analysed (drop-out rate=16.9%). The survival rate was 85%, and the success rate was 76%. The control group consisted of 46 patients (21F, 25M; median age 60.3±7.2years) who had undergone 102 root canal treatments. The survival rate was 88%, with 12 teeth lost during follow-up. The success rate was 73%. In the BP group, 55 teeth were restored normally (OC group) and 41 teeth were restored at the tissue level (TL group). No difference in the success or survival rate was observed between the BP and control groups (P>0.05). Univariate Kaplan–Meier analysis revealed that only tooth type significantly affected survival status in the BP group. The analysis revealed the clinical relevance of smoking, tooth location and initial PAI on patients’ health status (P&nbsp

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Purpose: To evaluate the factors affecting peri-implant marginal bone level of single platform-switched implants with a smooth neck placed at gingival level (tissue level) using a flapless technique. Materials and Methods: Consecutive healthy patients requiring dental implant rehabilitations were enrolled in this study. Titanium implants with a zirconium-oxide-blasted surface and a platform-switch neck tulip configuration were used. Loading was performed 3 months after insertion with a provisional resin crown and after approximately 15 days with a definitive ceramic crown. Peri-implant marginal bone level (MBL) was measured on periapical radiographs at 1, 3, 6, 12, 24, 36, and 48 months by a blinded assessor. The following parameters were evaluated: location (maxillary/mandibular), position (anterior/posterior), sex (male/female), smoke (yes/no), implant placement timing (immediate, early, delayed), gingival thickness (thin/thick), endodontically treated adjacent teeth (yes/no), and diameter (3.8/4.25/5.0 mm). Multilevel analyses exploring factors associated with MBL at 36 and 48 months were performed. Results: A total of 76 patients (42 women, 34 men; mean age: 55.6 ± 10.7 years) received 128 implant rehabilitations. The survival rate was 98.4%. MBL displayed an initial increase during the first months from insertion (preload period). Cumulative mean MBL at T48 was 0.99 ± 0.68, which was not statistically significant from the values at T24 to T36 (P >.05). Mandibular location, delayed implants, and presence of adjacent endodontically treated teeth showed higher bone loss at 36 months (P .05). Conclusion: Platform-switched implants placed nonsubmerged with a flapless approach showed a reduced bone loss progression in the first 4 years, as MBL remained stable at longer times (36 and 48 months). Implants placed with early and immediate timing showed reduced bone loss compared with delayed implants.

A pulp capping material must perform as a barrier and protect the dental pulpal complex by inducing the formation of a new dentin bridge or dentin-like tissue. Being a favorable condition for the healing process, the apatite forming ability of TheraCal (light-curable Portland-dimethacrylate cement) and Dycal (calcium hydroxide-based) pulp capping materials was studied in two simulated body fluids, i.e. Dulbecco’s Phosphate Buffered Saline (DPBS) and Hank’s Balanced Salt Solution (HBSS). The cements were analyzed before and after soaking in these media for different times (1–28 days) by ESEM-EDX, micro-Raman and IR spectroscopy. This data article refers to “An in vitro study on dentin demineralization and remineralization: collagen rearrangements and influence on the enucleated phase” (Di Foggia et al., 2019).

Aim To compare residual root-end filling material in apical root-end cavities following their removal with ultrasonic retrotips. Methodology Thirty single-rooted teeth were filled with Thermafil and AH Plus sealer. Root-ends were resected at 90°, 3 mm from the apex. Root-end cavities were prepared with diamond burs and ultrasonic retrotips and filled with one of three filling materials: group I: Retro-TC (calcium silicate-based cement), group II: IRM (Dentsply, Germany), group III: Vitrebond (3M ESPE, USA). After 30 days of storage, ultrasonic retrotips were used to remove materials from the root-end cavities. The ultrasonic application time was fixed at 60 s. Polyether impressions and replicas of the root-ends were made. Root apices and replicas were examined by one operator under a scanning electron microscope. Remnants of residual materials were evaluated using a four-level scoring system; fractures, smear layer and exposed dentinal tubules were also examined. Results Forty per cent of the specimens filled with Retro-TC revealed complete removal of the material with exposure of dentinal tubules, whilst 60% contained residual cement. Twenty per cent of specimens filled with IRM were completely devoid of material, whereas 80% had retained material. Ten per cent of specimens filled with Vitrebond retained a moderate amount of material whilst 90% had substantial retention of the material. Statistically significant differences were found (P

Bisphosphonates are synthetic drugs structurally similar to pyrophosphate in which the P-O-P is replaced by a P-C-P group. This chemical group makes bisphosphonates resistant to hydrolysis by physiological phosphatase and causes the high binding affinity of biphosphonates to calcium atoms of apatite crystals. Several "in vitro" studies were carried out using demineralizing solutions, such as lactic, acetic or citric acids. These solutions were able to cause the release of mineral ions like Ca++ or PO4--- and to induce demineralization beside several alterations of enamel to, or even the same as clinically detectable caries lesions. The use of alendronate may represent an initial different approach to obtain enamel surfaces able to resist lactic acid attacks. This study evaluated the effect of treatment with 10 mM alendronate solution on human dental enamel subjected to an acid challenge in a demineralizing acidic solution.