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PURPOSE To compare the flexural properties and the adhesion of Lactobacillus salivarius (LS), Streptococcus mutans (SM), and Candida albicans (CA) on heat-polymerized (CV), CAD-CAM milled (CAD), or 3D-printed (3D) Poly (methylmethacrylate) (PMMA). METHODS Ultimate Flexural Strength (UFS), Flexural Strain (FS) (%) at Flexural Strength, and Flexural Modulus (FM) of specimens (65.0��10.0��3.3 mm) from each PMMA group (n=6) were calculated by using the 3-point bending test. The surface roughness profiles (R) were measured before and after polishing with a contact profilometer. LS, SM, and CA adhesion on PMMA specimens (n=18) (10 mm in diameter, 3 mm in height) was assessed after 90 minutes and 16 hours by using scanning electron microscopy. The Kruskal-Wallis test with post hoc analysis was performed to compare the groups (alpha=0.05). RESULTS Mean UFS values were 80.79��7.64 MPa for CV, 110.23��5.03 MPa for CAD, and 87.34��6.39 MPa for 3D. Mean FS values were 4.37��1.04% for CV, 4.71��0.62% for CAD, and 6.19��0.13 % for 3D. Mean FM values were 2542��301 MPa for CV, 3435��346 MPa for CAD, and 2371��197 MPa for 3D. CAD had the lowest average R value (0.29��0.16 ��m) before polishing, and bacterial adhesion after 90 minutes of incubation. R value and microbial adhesion were not different amongst groups after polishing and 16 hours of incubation, respectively. CONCLUSION The CAD group displayed the best flexural properties, except for FS, the lowest roughness before polishing and bacterial adhesion after 90 minutes of incubation. All tested PMMAs had similar surface roughness after polishing, and microbial adhesion after 16 hours of incubation.

Bone tissue engineering strategies are emerging as attractive alternatives to autografts and allografts in bone tissue reconstruction, in particular thanks to their association with nanotechnologies. Nanostructured biomaterials, indeed, mimic the extracellular matrix (ECM) of the natural bone, creating an artificial microenvironment that promotes cell adhesion, proliferation and differentiation. At the same time, the possibility to easily isolate mesenchymal stem cells (MSCs) from different adult tissues together with their multi-lineage differentiation potential makes them an interesting tool in the field of bone tissue engineering. This review gives an overview of the most promising nanostructured biomaterials, used alone or in combination with MSCs, which could in future be employed as bone substitutes. Recent works indicate that composite scaffolds made of ceramics/metals or ceramics/polymers are undoubtedly more effective than the single counterparts in terms of osteoconductivity, osteogenicity and osteoinductivity. A better understanding of the interactions between MSCs and nanostructured biomaterials will surely contribute to the progress of bone tissue engineering.

Aims: The present study was designed to test the hypothesis that dental occlusion may have a role in mediating the effects of bruxism in temporomandibular disorders (TMD) patients. It aimed to answer the clinical research question: in a population of TMD patients with clinically diagnosed clenching-type bruxism, are the different TMD diagnoses associated with different occlusal features? Materials and methods: A total of 294 TMD patients (73% females, mean age 38.369.2 years) who were positive for a clinical diagnosis of clenching-type bruxism underwent an assessment in accordance with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) axis I, as well as a recording of nine occlusal features. Statistical analyses were performed to test the null hypotheses that: (1) no differences existed between the patients with or without the various occlusal features as for the prevalence of the various single and combined RDC/TMD group diagnoses (single variable analysis), and (2) having any specific occlusal feature makes no difference in distinguishing within the RDC/TMD diagnoses (multiple variable analysis). Results: The distribution of the different combination of RDC/TMD axis I diagnoses was significantly different in patients with laterotrusive interferences with respect to those without such interferences (chisquare515.209; P50.033) as well as in patients with a slide from retruded contact position (RCP) to maximum intercuspation (MI) .2 mm with respect to those without such slide (chi-square54.029; P50.012) and in those with or without molar class asymmetry (chi-square517.438; P50.015). Multinomial regression analysis showed that the model including the various occlusal features account for 20.4% of the variance for RDC/TMD diagnoses (Nagelkerke R 2 50.204) and allowed the rejection of the null hypothesis that having such specific occlusal features makes no difference in distinguishing within the RDC/TMD diagnoses. Conclusions: Within the limitations of this study, it can be suggested that in a population of patients with TMD and clinically-diagnosed clenching-type bruxism, the patterns of TMD diagnoses may be influenced, at least in part, by the presence of some features of dental occlusion, namely, slide RCP-MI, laterotrusive interferences, and molar asymmetry.

Silver (Ag) ions have well-known antimicrobial properties and have been applied as nanostrategies in many medical and surgical fields, including dentistry. The use of silver nanoparticles (Ag NPs) may be an option for reducing bacterial adhesion to dental implant surfaces and preventing biofilm formation, containing the risk of peri-implant infections. Modifying the structure or surface of bone grafts and membranes with Ag NPs may also prevent the risk of contamination and infection that are common when alveolar bone augmentation techniques are used. On the other hand, Ag NPs have revealed some toxic effects on cells in vitro and in vivo in animal studies. In this setting, the aim of the present paper is to summarize the principle behind Ag NP-based devices and their clinical applications in alveolar bone and dental implant surgery.

Recent advances in tissue engineering have drawn scientists to test the possibility of tooth engineering and regeneration. Tooth regeneration is normally referred to as the regeneration of the entire tooth or root that can be integrated into the jaw bone. This technology is still at its infancy and when it matures, it may be used to restore missing teeth and replace artificial dental implants when the tooth is damaged but still in a reparable condition, regeneration of parts of the tooth structure can prevent or delay the loss of the whole tooth. To engineer and regenerate a whole tooth, the cell source, tissue engineering strategies and specific scaffolds needed to be correct choose. Indeed, for example, to repair partly lost tooth tissues such as PDL, dentin, and pulp, one or two particular types of dental stem cells may be sufficient to fulfill the need. In light of such considerations, aim of the present chapter is to define the main strategies to isolate dental pulp stem cells, their characterisation and differentiation, tissue enngineering strategies and clinical applications for the creation of artificial tissue useful in odontoiatric field.

Background The aim of this study is to evaluate the prevalence of elongated styloid process in digital panoramic radiographs in a North Italian population in relation to age, gender and side. Material and methods This study was performed as a retrospective analysis on digital panoramic radiographs of 600 (271 males and 329 females) Italian patients between 6 and 87 years old. The styloid process length were measured using the measuring tool of Sidexis Software. It was measured from the point where it left the temporal bone plate to its tip. Styloid processes measuring more than 30 mm were considered elongated. Chi-squared and Fisher tests were used and the test is considered significant if the p-value is lower or equal to 0.05. Results Thirty-three per cent of the patients showed an elongated styloid process. Seventeen per cent were elongated on both right and left side, fifteen point nine per cent were elongated only in one side. Conclusions The prevalence of elongated styloid process was high and a progressive increase of the elongation prevalence was found in older groups. Key words:Elongated styloid process, Eagle's syndrome, panoramic radiograph.

The placement of implants immediately after tooth extraction is the ideal treatment option in selected cases. However, previous studies have shown that placing an implant does not avoid the shrinkage of the alveolar ridge. The aims of the present investigation were to evaluate bone dimensions after immediate implant placement with simultaneous grafting of the buccal gap, to determine if initial buccal bone width had an influence on bone remodelling and to compare bone volume changes using a flap or a flapless approach after 6 months of healing. Material and methods This prospective study included patients who required an extraction and a subsequent immediate implant placement at a non-molar site. In those cases where tooth extraction was not feasible with a flapless approach (test group) a mucoperiosteal flap was carefully elevated (control group). After extraction, a cone beam computed tomography (CBCT) was taken. Then, an implant was placed and the buccal gap was grafted using anorganic bovine bone. After 6 months of healing, a second CBCT was performed. A blinded investigator superimposed both images and performed a series of measurements to determine bone volume changes between the two time points. Results Thirty-five patients were included in this study, 20 of which belonged to the test group. All together, the differences between baseline and 6 months in buccal plate height, lingual 10 plate height and in ridge width at 2, 4 and 6 mm were 0.48±1.35; 0.58±1.51; 0.64±0.81; 0.59±1.36 and 0.52±1.16 respectively. Only a moderate correlation was observed between initial buccal plate width and buccal plate height at 6 months (p=0.0001). No statistically significant differences were observed between flap and flapless approach. Conclusion A mean reduction of around 0,5mm in height and width after placing immediate implants and filling the residual gap with anorganic bovine bone may be expected. No significant association between initial buccal bone width and ridge width at 6 months was seen. No statistically significant differences were found between the two treatment protocols although more ridge reduction was observed for the flap group.

A 27-year-old man presented an anterior open bite relapse. He had low tongue posture positioned anteriorly at rest and during swallowing and reported chronic difficulty in nose breathing. Head cone-beam computed tomography revealed nasal septum deviation, right turbinate hypertrophy, and left maxillary sinus congestion, which were thought to contribute to the breathing problem, encourage the improper tongue posture, and thereby cause the relapse. Multidisciplinary treatment involving an otorhinolaryngologist, an orthodontist, and a periodontist resolved the upper airway obstruction and corrected the malocclusion. The follow-up examination after 3 years 5 months demonstrated stable results.