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There is growing evidence that minimally invasive sinus augmentation works without the use of filler materials. This study assessed the bone integration and sinus projection of single-unit implants in the maxilla, which were placed approximately 18 years ago using a modified filler-free osteotome technique.Sixteen of the 24 treated patients of a former publication (treatment was performed between 2001 and 2004) were reassessed after a mean implant loading period of 17.5 years. The treated posterior areas were evaluated using cone-beam computed tomography (CBCT), and as a primary outcome parameter, sinus projection was determined in sectional views at the mesial, distal, buccal, and oral sites. Additionally, the percentage of alveolar bone contact was determined with respect to the implant length. Conventional radiographs were used to determine marginal bone levels. Additionally, plaque, bleeding on probing, and probing pocket depth were measured. The reconstructions were checked for chipping and other technical complications such as loss of retention, screw loosening, and screw fracture.The mean age of the included patients was 72.8 ± 8.5 years. Two implants were lost. Therefore, fourteen implants were available for CBCT evaluation. The highest sinus projection of 2.1 ± 1.7 mm was observed in the distal aspect, while it was 1.1 ± 1.5, 0.9 ± 1.2, and 0.9 ± 1.1 mm at the mesial, buccal, and oral sites, respectively. The maximal sinus projection in one case was 6.7 mm. The percentage calculation of osseous implant integration (in mm ± standard deviations) with respect to the selected implant length at the mesial, distal, buccal, and oral sites showed values ranging from, 87.9 ± 16.0, 78.4 ± 20.3, 91.0 ± 12.5, and 90.5 ± 11.1%, respectively. Five implants displayed probing pocket depths of more than 4 mm with bleeding; all implants had less than 1 mm of bone loss in the observation period, that is, implants had mucositis. Six of 14 crowns showed small chippings within the ceramic veneering. One case of screw loosening was reported in medical history.This study showed that implant placement in non-augmented sinuses resulted in good clinical results. The sinus projection, even if persistent and present, leads to no functional impairments. Given adequate maintenance, marginal bone levels remain constant and peri‑implant health can be observed. Moreover, these results represent only a small cohort; and therefore, should be interpreted with caution. However, in view of the existing literature, these highly promising results are in line with other findings.To the best of our knowledge, this dataset is the report with the longest follow-up. Overall, implants placed in the sinus without fillers represent a valuable alternative for tooth replacement in a minimally interventional manner.

Objectives: To prepare experimental composites with bioactive glass (BG) and investigate their release of calcium (Ca), phosphate (PO4), and fluoride (F), as well as pH changes and apatite precipitation after immersion. Methods: Experimental composites were prepared with 0, 10, or 20 wt% of either BG 45S5 or a customized low- Na F-containing BG. Three commercial ion-releasing materials were used for reference. Material specimens were immersed in lactic acid (pH = 4.0) and artificial saliva (pH = 6.4). Ion concentrations (atomic absorption spectrometry for Ca, UV–vis spectrometry for PO4, and ion-selective electrode for F) and pH were measured after 4, 8, 12, 16, 20, 24, 28, and 32 days. After immersion, composite specimens were analyzed using scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy. Results: Material- dependent concentrations of Ca, PO4, and F were measured in the lactic acid solution, while a decrease of Ca and PO4 concentrations was observed in artificial saliva. The uptake of ions from artificial saliva indicates their precipitation on specimen surfaces, which was supported by the results of SEM and FTIR investigations. In experimental composites functionalized with both bioactive glass types and a commercial “alkasite” material, apatite was precipitated not only in artificial saliva but also in the lactic acid solution. Conclusions: Experimental BG-containing composites and selected commercial restorative materials demonstrated the potential for releasing multiple ion types and increasing pH. Clinical significance: The observed effects can be beneficial for preventing demineralization and promoting remineralization of dental hard tissues, while apatite precipitation can additionally help in sealing marginal discontinuities.

Objectives This study aimed to investigate the additional clinical benefit of tricalcium phosphate (TCP) (-containing) biomaterials compared to open flap debridement (OFD) in periodontal infrabony defects. Data A literature search was conducted in Pubmed, Embase and Cochrane library for entries published up to 14th July 2021. All randomized controlled trials (RCTs) that compared a TCP (-containing) material with OFD and studies that assessed a beta-TCP group alone, with vertical defect sites with PPD of ≥ 6 mm and/or presence of infra-bony defects of ≥ 3 mm and a minimum follow-up of 6 months were included. Risk of bias was assessed with the Oxford scale. The random-effects (RE) model was synthesized as differences between weighted average (MD) for probing pocket depth (PPD) and clinical attachment level (CAL) between TCP and OFD groups. An RE analysis was also performed for the beta-TCP group alone. Study selection Data from 16 RCTs were included in the analysis. Six studies that represented 151 patients and sites were selected for meta-analysis. The overall MD with 95% CI at 6 months was calculated to be -0.47 [-0.83, -0.12; P=0.0087] and -1.06 [-1.67, -0.46; P=0.0006] for PPD and CAL, respectively. Whereas MD at 12 months for PPD and CAL was -0.89 [-1.54, -0.23; P=0.0078] and -1.25 [-1.85, -0.66; P Conclusions The results of the study suggest that the use of a TCP (-containing) material may have the potential for additional clinical improvement in PPD and CAL compared with OFD in infrabony defects, given the limitations of the included evidence. Clinical significance The use of TCP as a bone graft substitute is becoming increasingly common. Therefore, it would be advantageous if an adjunctive benefit in the regeneration of infrabony defects could be demonstrated to facilitate material selection. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Objectives To investigate the effect of rapid high-intensity light-curing on the marginal integrity of four bulk-fill composites, including two materials specifically designed for high- intensity curing. Methods Class V cavities were prepared on buccal surfaces of intact human molars with simulated pulpal pressure, filled in a single increment and light-cured using a conventional (10 s @ 1, 340 mW/cm2) or high-intensity (3 s @ 3, 440 mW/cm2) protocol. The restorations were subjected to thermo-mechanical loading (TML) comprising 1, 200, 000 mechanical loading cycles and 3, 000 thermocycles. Quantitative margin analysis was performed before and after TML using a scanning electron microscope, and the marginal integrity was expressed as percentage of continuous margin (PCM). Results All PCM values measured before TML were statistically similar regardless of the material and curing protocol (p>0.05). A statistically significant effect of the curing protocol (p = 0.021) was identified only after TML for one material. PCM was significantly diminished by TML (p0.05). Compared to these values, significantly lower PCM after TML was identified for the flowable composites cured with the high-intensity protocol (p = 0.001–0.045). Conclusion In most cases, high-intensity and conventional curing generally led to similar marginal integrity. Although all of the investigated composites initially performed similarly well, the flowable composites light-cured using the high-intensity protocol showed a significantly inferior marginal integrity compared to the sculptable composites after loading. Clinical significance Rapid high- intensity light-curing cannot be recommended for flowable bulk-fill composites since it may compromise the tooth-restoration interface.

Objectives The study evaluated the suitability of pure crystalline hydroxyapatite (HA) as a substitute for human (H) and bovine (B) enamel in erosion experiments. Methods Human and bovine enamel and hydroxyapatite specimens (n = 18 each) were submitted to demineralisation by HCl at pH values of 3.0, 2.6 and 2.0 (1.0, 2.5, and 10 mmol/l concentration). Specimens were eroded in a superfusion chamber for 7 min (flow rate: 1 μl/s). Multiple fluid samples were taken per specimen throughout the exposure period. The dissolved calcium content was measured using a colorimetric assay with Arsenazo III reagent, to serve as surrogate for erosive substance loss. Additionally, erosive tissue loss was quantified by profilometry. Differences in erosive substance loss were assessed by the Kruskal-Wallis and Conover’s posthoc test. Results Good agreement in erosive substance loss between HA and human specimens was found at pH 2.6, as no statistically significant difference and considerable overlap of their respective interquartile ranges was observed. At pH 2.0 and 3.0, a statistically significant difference between HA and human and bovine enamel was determined. HA consistently tended to have lower mean dissolution rates, with a maximum deviation from human enamel of -16% at pH 3. It displayed lower specimen variability with an average coefficient of variation of 17%, compared to 25% (H) and 25% (B), respectively. Conclusions Crystalline hydroxyapatite may not be suitable for full substitution of biologic enamel in erosion experiments focusing on absolute measurement values, but is useful for establishing consistent relative trends between erosive agents due to biosimilar erosion behavior and lower experimental variability. This is especially true for preliminary studies where approval for use of biological samples is restricted. Clinical significance Crystalline hydroxyapatite is a useful substitute of human or bovine enamel in experiments studying chemical aspects of dental erosion.

Objectives To compare the effect of high-intensity (3 s with 3440 mW/cm2) and conventional (10 s with 1340 mW/cm2) light-curing on shrinkage properties and degree of conversion of conventional and bulk-fill resin composites, including two composites specifically designed for high-intensity curing. Methods Real-time linear shrinkage and shrinkage force of 1.5 mm thick composite specimens were measured for 15 min after the start of light-curing using custom-made devices. From the shrinkage force data, maximum shrinkage force rate and time to achieve maximum shrinkage force rate were determined. Degree of conversion was measured using Fourier transform infrared spectrometry. Results Flowable composites showed significantly higher linear shrinkage compared to sculptable composites (1.93–2.91 % vs. 1.15–1.54 %), as well as significantly higher shrinkage forces (18.7–24.4 N vs. 13.5–17.0 N). Degree of conversion amounted to 45.8–60.1 %. For high-intensity curing, degree of conversion was significantly lower in three out of seven composites, whereas shrinkage forces were either increased, decreased, or unchanged compared to conventional curing. For high-intensity curing, maximum shrinkage rates were 6–61 % higher, whereas times to achieve maximum shrinkage force rate were 15–53 % shorter compared to conventional curing. Composites specifically designed for high-intensity curing showed shrinkage parameters comparable to other investigated composites. Conclusion Shrinkage behavior under conditions of high-intensity light-curing was material-dependent. Shrinkage force kinetics were more strongly affected by high-intensity curing than absolute values of linear shrinkage and shrinkage force. Clinical significance Despite being attractive for its convenience, high-intensity curing can lead to considerably faster development of shrinkage forces in the early stage of polymerization.

Objectives: To investigate the influence of pre-heating of high-viscosity bulk-fill composite materials on their degree of conversion and shrinkage force formation. Methods: Four bulk-fill composite materials (Tetric EvoCeram Bulk Fill-TECBF, x-tra fil-XF, QuixFil-QF, SonicFill-SF) and one conventional nano-hybrid resin composite (Tetric EvoCeram- TEC) were used. The test materials were either kept at room temperature or pre-heated to 68 degrees C by means of a commercial heating device, before being photoactivated with a LED curing unit for 20 s at 1170 mW/cm(2). Shrinkage forces (n = 5) of 1.5-mm-thick specimens were recorded in real-time for 15 min inside a temperature-controlled chamber at 25 degrees C (simulating intraoral temperature after rubber dam application) with a custom- made stress analyzer. Degree of conversion (n = 5) was determined at the bottom of equally thick (1.5 mm) specimens using Fourier transform infrared spectroscopy. Data were analyzed with Student's t-test, ANOVA and Tukey's HSD post-hoc test (alpha = 0.05). Results: Composite pre-heating significantly increased the degree of conversion of TECBF, but had no effect on monomer conversion of the other materials investigated. For each of the test materials, pre-heated composite generated significantly lower shrinkage forces than room- temperature composite. At both temperature levels, TECBF created the significantly highest shrinkage forces, and QF caused significantly higher shrinkage forces than both XF and TEC. Conclusions: Both the composite material and the pre-cure temperature affect shrinkage force formation. Pre-heating of bulk-fill and conventional restorative composites prior to photoactivation decreases polymerization- induced shrinkage forces without compromising the degree of conversion. Clinical significance: Composite pre-heating significantly reduces shrinkage force formation of high-viscosity bulk-fill and conventional resin composites, while maintaining or increasing the degree of monomer conversion, dependent upon the specific composite material used. (C) 2015 Published by Elsevier Ltd.

Objectives The aim of the present pilot study was to test whether or not posterior zirconia–ceramic fixed dental prostheses (FDPs) with pressed veneering ceramic exhibit less chipping than FDPs with layered veneering ceramics. Methods Forty patients (13 female, 27 male; mean age 54 years (range 26.1–80.7 years) in need of one maxillary or mandibular three-unit FDP in the second premolar or molar region were recruited and treated at two separate centers at the University of Zurich according to the same study protocol. The frameworks were made out of zirconia using a CAD/CAM system (Cerec Sirona, Bensheim, Germany). The patients were randomly assigned to either the test group (zirconia frameworks veneered with pressed ceramic; IPS e.max ZirPress, Ivoclar Vivadent AG, Schaan, Liechtenstein; n = 20) or the control group (layered veneering ceramic; IPS e.max Ceram, Ivoclar Vivadent AG, Schaan, Liechtenstein; n = 20). All FDPs were adhesively cemented and evaluated at baseline (i.e., cementation), at 6 months and at 1 and 3 years of clinical service. The survival of the reconstruction was recorded. The technical outcome was assessed using modified United States Public Health Services (USPHS) criteria. The biologic parameters analyzed at abutment teeth and analogous non-restored teeth included probing pocket depth (PPD), plaque control record (PCR), bleeding on probing (BOP), and tooth vitality (CO2). Data was descriptively analyzed and survival was calculated using Kaplan–Meier statistics. Results 36 patients (25 female, 11 male; mean age 52.3 years) with 18 test and 18 control FDPs were examined after a mean follow-up of 36 months (95% CI: 32.6–39.1 months). Comparison of groups was done by Crosstabulation showing even distribution of the respective restored teeth amidst the groups. Survival rate was 100% for both test and control FDPs. Chipping of the veneering ceramic tended to occur more frequently in test (n = 8; 40%) than in control (n = 4; 20%) FDPs, albeit not significantly (p = 0.3). No further differences of the technical outcomes of test and control FDPs occurred.In both test and control group healthy conditions and no difference of the biologic parameters at the abutment and un-restored teeth was found. Conclusion Zirconia FDPs with pressed and layered veneering ceramics exhibited similar outcomes at 3 years. A trend to more chipping of the pressed veneering ceramic, however, was observed. Clinical significance Posterior restorations with zirconia frameworks are a viable treatment method. When restoring posterior teeth with all-ceramic restorations, care providers should be aware of the higher rate of chipping compared to the published data on conventional metal-ceramic restorations.

Objectives To investigate the effect of saliva substitutes on enamel erosion in vitro. Methods A total of 204 bovine enamel samples were embedded in acrylic resin and allocated to 17 groups (n = 12). The specimens were eroded in an artificial mouth (3 days; 6 × 30 s/days, flow rate: 2 ml/min) using citric acid (pH: 2.5). Immediately after the erosive attacks, saliva substitutes (12 sprays, 3 gels) were applied. Between the erosive cycles the specimens were rinsed with artificial saliva (flowrate: 0.5 ml/min). A SnCl2/AmF/NaF-containing mouthrinse was used as positive control, water spray served as negative control. Enamel loss was measured profilometrically and the data were analyzed using one-way ANOVA followed by Scheffe’s post hoc tests (p Results Four saliva substitutes increased enamel erosion, probably due to the low pH or the content of citric acid. Several saliva substitutes were able to reduce enamel erosion significantly by 60–90% (in the range of the positive control). The protective potential of these products was in the range of the positive control (reduction of enamel loss to 30% of negative control). The erosion-protective potential of these high-viscous products is probably related to their film-forming properties, leading to a mechanical protection of the surface. Conclusion Saliva substitutes containing a very low pH exhibit a distinct erosive potential, while most high-viscous products present an erosion-protective effect. It can be recommended that patients suffering from xerostomia and at high risk for dental erosion should use high-viscous saliva substitutes, but should avoid saliva substitutes with low pH or containing citric acid. Clinical significance It can be recommended that patients suffering from xerostomia and at high risk for dental erosion should use high-viscous saliva substitutes, but should avoid saliva substitutes with low pH or containing citric acid.

Objectives The aim of this study was to evaluate the effects of chemical activation of hydrogen peroxide (HP) gel on colour changes and penetration through the tooth structure. Methods One hundred and four bovine incisors were used. One dentine (CD) disc and one enamel–dentine (ED) disc were prepared from each tooth. They were positioned over artificial pulpal chambers and the bleaching was performed with an experimental 35% HP gel. Two control and six experimental groups were prepared. In the positive control group (PC) no chemical activator was used. In the negative control group (NC) the specimens did not receive any bleaching. Each experimental group received a different chemical activator (manganese gluconate—MG; manganese chlorite—MC; ferrous sulphate—FS; ferrous chlorite—FC; and mulberries root extract—MRE). After the bleaching procedure a sample of solution was collected from the artificial pulpal chamber and the HP concentration was measured. The data were analysed using ANOVA, Tukey's, and Dunnett's tests. Results The groups MG and FS showed a significantly lower penetration of HP than the PC group. For the parameter Delta E, all the groups, with the exception of the group MRE, showed a significantly higher means in relation to the PC group in ED colour. For dentine colour, just the groups MG and FS had significant differences in relation to PC. Conclusions The addition of MG and FS decreases the penetration of HP. The chemical activation using metal salts tested was effective in increasing the bleaching effect.

OBJECTIVES: The purpose of this study was to assess the shear bond strength (SBS) of metal brackets when placed with a caries protective adhesive patch. METHODS: Forty stainless steel brackets (Ormco) were bonded to 40 bovine enamel samples according to the following conditioning/bonding procedures using a resin-based orthodontic luting material (Heliosit Orthodontic, N=10 per group): (A) 35% phosphoric acid (30s), rinse and dry; (B) as in A but additional placement of a prototype adhesive patch (Ivoclar Vivadent) using a bonding agent (Heliobond); (C) application of a two-step self-etch adhesive (AdheSE); (D) as in C but additional patch placement. Samples were stored at 37 degrees C for 24h. SBS was measured with a universal testing machine with a crosshead speed of 0.5mm/min and the adhesive remnant index (ARI) was determined under a stereomicroscope (16x). RESULTS: Mean SBS (standard deviation) values were as follows: (A) 16.6 (6.4)MPa; (B) 12.2 (5.8); (C) 12.9 (5.0); and (D) 10.5 (4.7). Analysis of variance followed by Bonferroni correction revealed no statistically significant differences. In 2 (B) and 4 (D) specimens, complete retention of the adhesive patch was observed. CONCLUSIONS: All treatment groups showed adequate bond strength values. The adhesive patch could therefore be applied in combination with orthodontic brackets and seal the enamel adjacent to the bracket.

OBJECTIVES: To investigate the use of computer-assisted densitometric image analysis (CADIA) to detect incipient approximal carious lesions in vitro and to compare areas of demineralization and mechanically induced lesions by radiographic visual inspection. METHODS: Thirty-six extracted non-carious human molars were demineralized in a defined approximal area of interest (AOI) using a gel system (pH 4.8) applied over 15 weeks. Standardized digital radiographs were taken before and after creation of caries-like lesions and grayscale values were measured within the AOI. For another group of eight teeth, artificial defects were mechanically induced by a diamond bur and densitometric analysis was performed. Statistical significance was tested using the Wilcoxon test and set at p < or = 0.05. In addition, radiographs were interpreted by visual examination by six experienced dentists. The sensitivity and specificity for both study groups were determined in comparison to a baseline group of untreated teeth. Polarized light microscopy and SEM analysis were used to evaluate changes in the subsurface mineralization pattern and surface micromorphology. RESULTS: Densitometric comparison of images from identical regions in control teeth revealed no significant grayscale value differences within the AOI, whereas a significant decrease (p < or = 0.05) was observed in the demineralized group. Mechanically induced lesions also showed a significant densitometric decrease (p < or = 0.05). The sensitivity of visual inspection of radiographs of demineralized areas was 0%. In contrast, the sensitivity for the detection of a mechanical defect of 0.1mm, which was the same subsurface extension as the histologically determined demineralization, increased to 52%. Specificity was 100% for all groups. CONCLUSIONS: CADIA is able to detect very small changes in mineralization of incipient carious approximal lesions in vitro. The findings presented in this investigation may improve the subtraction method used for diagnosis and monitoring of approximal caries, as well as prophylactic measures.

OBJECTIVES To test the hypothesis that a material with higher water absorption than polyvinylidene fluoride (PVDF) could increase the yield of target molecules from exposed dentine. METHODS In a series of standard tests, different cellulose membranes were compared to a PVDF counterpart for their ability to absorb water and release protein. In a subsequent randomized clinical trial, the cellulose material with the most favourable values was compared to PVDF regarding the levels of MMP-2 that could be collected from exposed dentine of healthy human teeth during filling replacement. MMP-2 levels were determined by enzyme-linked immunosorbent assay (ELISA). Data from the laboratory experiments were compared between materials using the appropriate parametric tests. The frequency of cases yielding quantifiable levels of MMP-2 was compared between materials by Fisher's exact test. The level of significance was set at 5%. RESULTS The cellulose membrane with the largest pore size (12-15μm) absorbed significantly (P

Objective To compare the protective potential of a conventional adhesive, a caries infiltrant and a combination of both against acidic challenge in vitro. Methods One-hundred-and-fifty discs from bovine lower central incisors were fabricated. Seventy-five samples remained untreated, whereas the other half was subjected to a demineralisation process (14 days, acidic buffer, and pH 5) to create artificial enamel lesions. Specimens were then radioactively irradiated, and each 15 sound and demineralised specimens were treated with a caries infiltrant (Icon, DMG), an unfilled adhesive (Heliobond, IvoclarVivadent) or a combination of infiltrant and adhesive. Specimens treated with the adhesive followed by a flowable composite (TetricEvoFlow, IvoclarVivadent) served as positive control, while untreated specimens served as negative control. All samples were then subjected to lactic acid for 3 weeks at pH 4. Loss of apatite was determined using the radiochemical method of liquid scintillation. Data were statistically analysed by Kruskal–Wallis-test, one-way ANOVA and Scheffe's post hoc tests (p ≤ .05). Results In both sound enamel and artificial caries lesions, untreated specimens showed the highest rate of apatite loss, whereas enamel treated with the adhesive and the flowable composite showed almost complete protection surface against dissolution. The caries infiltrant, the adhesive and the combination of both were able to decrease enamel dissolution, but the adhesive and the combination of adhesive and infiltrant were more effective than the infiltrant alone. Conclusion Within the limitations of this in vitro study, the application of an adhesive (alone or in combination with the caries infiltrant) is more effective to protect enamel dissolution than the infiltrant alone.

Resin infiltration is considered as a treatment option for initial caries lesions. As cavitated early lesions might require additional restorative intervention, a caries infiltrant might be also used for enamel conditioning prior to composite insertion. This study aimed to analyse the shear bond strength of a flowable composite to sound and demineralised enamel pretreated with a caries infiltrant, a conventional adhesive or a combination of both.Flattened bovine enamel specimens (n=120) were either demineralised (14 d, acidic buffer, pH 5) or remained untreated. Sound and demineralised specimens (each n=20) were then treated with: (1) 35% phosphoric acid, conventional adhesive, (2) 15% hydrochloric acid, caries infiltrant or (3) 15% hydrochloric acid, caries infiltrant, conventional adhesive. Shear bond strength of a flowable composite was tested after 24 h water storage (37°C) and statistically analysed (ANOVA, p≤0.05). The mode of failure was assessed microscopically at 25× magnification.On demineralised enamel, the combination of caries infiltrant and conventional adhesive showed significantly higher shear bond strength values than the conventional adhesive alone, while both being not significantly different from group 2. No significant differences between the groups could be detected on sound specimens. A higher percentage of cohesive failures could be observed in demineralised samples of group 2 (40%) and 3 (65%), while all other specimens presented almost only adhesive failures.The use of a caries infiltrant before application of a conventional adhesive did not impair bonding to sound and demineralised enamel and might be beneficial as a pretreatment in demineralised enamel.