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Objectives Special needs patients are prone to insufficient oral care and subsequent caries or periodontitis. The aim of this retrospective study was the assessment of demand for restorative therapy and tooth extractions under general anesthesia in adults with intellectual and/or physical disablement (IPD) or psychiatric disorders (PDs) with inherent dentist phobia at the University Hospital of Innsbruck with regard to demographic factors. Materials and methods A total of 444 consecutive cases of scheduled dental general anesthesia (DGA) in adults from 2003 to 2014 were included. From patient files, demographic data, the presence of either IPD or a PD, attested by a mandatory certificate, and restorative therapy and tooth extractions performed under DGA were obtained. Data analysis was carried out by means of descriptive and comparative statistics. Results Four hundred two cases (mean age 37.5 ± 13.87 years) assigned to 283 individuals with IPD and 42 cases (mean age 36.09 ± 13.03 years) assigned to 39 individuals with PDs arose in the observed period. Patients with PDs required significantly more restorations (in 7.98 ± 5.4 versus 5.34 ± 4.41 teeth; p = 0.002; Mann-Whitney U test) and extractions (of 4.86 ± 4.51 versus 2.6 ± 3.96 teeth; p < 0.001; Mann-Whitney U test) than patients with IPD. Conclusions Demand for dental treatment was high in the collective of special needs patients. Oral health status was worse in patients with PDs than in patients suffering IPD. Clinical relevance While in patients with severe disablement, DGA presents the only treatment option, specific preventive programs should be implemented for patients with minor disablement or dentist phobia. In these patients, alternative approaches should be promoted.

Purpose Various resin cements and priming agents are available for adhesive luting of zirconia restorations. The purpose of this study was to investigate how cement type and priming protocol affect the shear bond strength on zirconia ceramics. Materials and Methods Yttria‐stabilized tetragonal zirconia polycrystalline ceramic cylinders were bonded to flat zirconia ceramic surfaces using 7 commercially available resin cements. Ten specimens of each cement group were pretreated with a universal primer, and 10 specimens per group were bonded without pretreatment. In addition, 10 specimens per group were pretreated with system‐specific zirconia primers, which were available for 3 cements. Altogether, 170 bonded specimens were water‐stored, thermal‐cycled, and then submitted to shear bond strength tests. The shear bond strength and the fracture types were documented. Differences in shear bond strengths were assessed using 2‐way ANOVA with post‐hoc test (α = 0.05). A point‐biserial correlation was run between the fracture patterns and the shear bond strengths. Results The mean shear bond strengths of cements in the unprimed group showed large variations between 2.52 ± 3.01 (mean ± SD) MPa and 33.15 ± 7.35 MPa. Pretreating the specimens with a universal primer improved the shear bond strengths significantly in all groups (p < 0.05) with a range of 21.80 ± 12.51 to 57.20 ± 11.40 MPa. The system‐specific primers also improved the shear bond strength significantly, compared to the unprimed group (p < 0.01); however, only one system‐specific primer achieved a shear bond strength superior to the universal primer (p < 0.01). There was also a statistical correlation between the fracture type and the shear bond strength (p < 0.0005), with cohesively fractured specimens showing higher shear bond strengths (37.24 ± 19.87 MPa) than adhesively fractured specimens (23.10 ± 17.65 MPa) (p < 0.001). Conclusion Using universal primer can enhance the maximal shear bond strength of zirconia.

This study investigated the influence of several dentin bonding agents, resin composites and curing modes on push-out bond strength to human dentin. 360 extracted caries-free third molars were prepared, cut into slices, embedded in epoxy resin and perforated centrally. One half of the specimens (180) were treated by using one-step adhesive systems and the other half (180) with multi-step adhesive systems. Subsequently, the cavities were filled with either universal, flowable or bulk-fill resin composite according to the manufactures’ product line and cured with either turbo or soft start program. After storage the push-out test was performed. The data was analyzed using Kolmogorov-Smirnov, three- and one-way ANOVA followed by the Scheffé post-hoc test, unpaired two-sample t-test (p < 0.05). The strongest influence on push-out bond strength was exerted by the resin composite type (partial eta squared ηP2 = 0.505, p < 0.001), followed by the adhesive system (ηP2 = 0.138, p < 0.001), while the choice of the curing intensity was not significant (p = 0.465). The effect of the binary or ternary combinations of the three parameters was significant for the combinations resin composite type coupled adhesive system (ηP2 = 0.054, p < 0.001), only. The flowable resin composites showed predominantly mixed, while the universal and bulk-fill resin composite showed adhesive failure types. Cohesive failure types were not observed in any group. Multi-step adhesive systems are preferable to one-step adhesive systems due to their higher bond strength to dentin. Flowable resin composites showed the highest bond strength and should become more important as restoration material especially in cavity lining. The use of a soft start modus for polymerization of resin composites does not enhance the bond strength to dentin.