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Aim: The aim of this study was to evaluate clinical features that might be related to success rates of autotransplantation of molars with complete root formation. Materials and methods: A group of 60 patients with completely formed third molars autotransplanted to a different molar socket was followed for a medium period of 5 years and 5 months. Extreme care was used in order to preserve the vitality of the periodontal ligament cells. The same technique was applied for all teeth despite different anatomies. Descriptive statistics was performed. The association of the various factors with failures was assessed by using the Fisher’s exact test and a p-value of 0.05 was considered as significance threshold. Results: Autotransplantation was found to be a reliable method to replace extracted molar teeth with closed apices. The two major factors that positively influenced the outcomes were fixation with splint and a periodontal probing pocket depth less than 4 mm after the initial healing period. The technique resulted in a suitable well-conserved socket and donor tooth, after the extraction. Conclusion: An accurate case evaluation was critically important in order to identify the risks prior to surgery and to select the right patients for this procedure. Autotransplantation of third molar teeth is a feasible approach to replace compromised mature molars. Proper stabilization of the transplanted tooth is strategical for the success of this procedure. A conservative approach to unerupted wisdom teeth is also recommended. Clinical significance: Dental implants and fixed prostheses have been utilized to replace missing teeth, and orthodontic space closure can be sometimes an effective treatment option. Tooth autotransplantation can be a reliable and less invasive clinical alternative when an appropriate donor site is available

OBJECTIVES There are several parameters that influence the degree of conversion of dual cement, such as: the type of light source used for the polymerization, the intensity of the light source, the thickness of the restoration and the translucency of the material used for the restoration. The purpose of this study was to investigate the effect of translucency of ceramic material on the degree of conversion of a dual- cure resin cement used to lute endocrowns. MATERIALS AND METHODS A freshly extracted first maxillary molar, without any dental caries, was used and prepared to receive an endocrown, according to Bindl and Mörmann criteria. The cavity preparation was acquired by an intraoral scanner (Cerec Omnicam, Dentsply Sirona, Charlotte, North Carolina) with the aim of executing the entire workflow digitally, from the design to the milling of endocrowns. In this way, 12 endocrowns, with 4.5 mm thickness, were produced by a milling machine (Cerec MCXL Wounder, Dentsply Sirona, Charlotte, North Carolina). The tested material was zirconia- reinforced lithium silicate with a high translucency (HT, n = 6) (Celtra Duo, Dentsply Sirona, Charlotte, North Carolina) and with a low translucency (LT, n = 6) (Celtra Duo, Dentsply Sirona, Charlotte, North Carolina). After applying an insulator (Separating Fluid, Ivoclar, Schaan, Liechtenstein) to the tooth, the dual cement (Calibra Dual Resin Cement, Dentsply Sirona, Charlotte, North Carolina) was applied to the endocrown. The endocrowns were placed on the tooth one by one and cured for 60 s using a LED light-curing unit (Valo, Ultradent, South Jordan, Utah) with a light intensity of 1000 mW/cm2. The excesses of dual cement were removed by using a probe. Additionally, six samples of dual cement, sized 5.0×7.0 mm, were prepared with a thickness of 1.0 mm, serving as control group (Control) and polymerized for 60 s through a Mylar strip. The microhardness (Vickers) of the dual cement was evaluated at the bottom of the luted endocrowns and the controls. The results were statistically analyzed with one-way ANOVA and Fisher’s test (p 0,05). CONCLUSIONS The microhardness of the dual cement is strongly dependent on both the translucency of the material with which endocrowns are produced. A low translucency leads to a significantly lower degree of conversion, which cannot guarantee a long-lasting restoration. CLINICAL SIGNIFICANCE Dual cements have been designed to ensure an optimal degree of conversion, regardless of the presence or absence of a light source and its intensity. This does not apply in the case of their use for endocrown luting procedures. In fact, the degree of conversion of dual cement depends not only on the type of light source and its intensity, but also and above all on the translucency of the restoration. Different levels of translucency affect the microhardness of the luting resin cement, potentially affecting its adhesive strength and, ultimately, the longevity of the chosen prosthodontic treatment.

PURPOSE: To evaluate the activity of a methacryloyloxydodecylpyridinium bromide (MDPB)-containing self-etching primer (Clearfil Protect Bond) against Streptococcus mutans and its ability to reduce biofilm formation on standardized experimental Class I restorations in vitro. MATERIALS AND METHODS: Forty experimental Class I round restorations were prepared on enamel-dentin slabs using different adhesive strategies: group 1 = MDPB-containing adhesive system (Clearfil Protect Bond); group 2 = MDPB-free self-etching adhesive system (Clearfil SE Bond); group 3: MDPB-containing self-etching primer in combination with a fluoride-free bonding agent; group 4: MDPB-free self-etching primer in combination with a fluoride-containing bonding agent; group 5: a three-step etch-and-rinse adhesive system (Adper Scotchbond Multi Purpose). A Streptococcus mutans biofilm was grown for 48 h on the restoration surfaces and subsequently evaluated using scanning electron microscopy on three different areas: enamel, composite, and interface surfaces. Statistical analysis was performed by multiple ANOVA after data transformation. RESULTS: Specimens in groups 2, 4 and 5 showed greater biofilm formation than those in groups 1 and 3 (p < 0.001) on all investigated substrates (enamel, composite, and interface areas). CONCLUSIONS: Specimens prepared with an MDPB-containing primer exhibited significant decreases in biofilm formation on Class I restorations in vitro. Further in vitro and in vivo studies are required to clarify the role of quaternary ammonium compounds in reducing bacterial biofilm formation on restoration surfaces.

Receptor endocytosis is a fundamental step in controllingthe magnitude, duration, and nature of cellsignaling events. Confl uent endothelial cells are contactinhibited in their growth and respond poorly to theproliferative signals of vascular endothelial growth factor(VEGF). In a previous study, we found that the associationof vascular endothelial cadherin (VEC) with VEGF receptor(VEGFR) type 2 contributes to density- dependent growthinhibition (Lampugnani, G.M., A. Zanetti, M. Corada,T. Takahashi, G. Balconi, F. Breviario, F. Orsenigo,A. Cattelino, R. Kemler, T.O. Daniel, and E. Dejana.2003. J. Cell Biol. 161:793–804). In the present study,we describe the mechanism through which VEC reducesVEGFR-2 signaling. We found that VEGF induces theclathrin- dependent internalization of VEGFR-2. WhenVEC is absent or not engaged at junctions, VEGFR-2 isinternalized more rapidly and remains in endosomalcompartments for a longer time. Internalization does notterminate its signaling; instead, the internalized receptoris phosphorylated, codistributes with active phospholipaseC–γ, and activates p44/42 mitogen- activated proteinkinase phosphorylation and cell proliferation. Inhibition ofVEGFR-2 internalization reestablishes the contact inhibitionof cell growth, whereas silencing the junction-associateddensity-enhanced phosphatase-1/CD148 phosphataserestores VEGFR-2 internalization and signaling. Thus,VEC limits cell proliferation by retaining VEGFR-2 atthe membrane and preventing its internalization intosignaling compartments.