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Objective of this study was to assess the influence of the subcrestal placement level of short implants with a locking-taper connection design on crestal bone levels and soft tissues health.A clinical retrospective case-control study was conducted between May 2013 and September 2013. The sample was composed of patients who had received at least one 5-to-8-mm-long, plateau-design implant with a locking-taper connection system (Bicon LLC, Boston, MA, USA) in posterior areas of maxilla and mandible, in the period between January 2009 and Dicember 2011. A radiographic evaluation of the degree of subcrestal positioning(t0) was conducted to identify two implant groups: Group 1 was composed of implants placed less than 2 mm under the crestal bone; Group 2 was composed of implants placed 2 mm or more under the crest. The primary outcome variables were the crestal bone levels and the peri-implant bone loss between prosthetic loading and last control visit (t1àt2). Clinical parameters including the keratinized gingival (KG) width, modified bleeding index (mBI), modified plaque index (mPI), and probing depth (PD) were assessed at the follow-up visit. T tests were conducted to identify statistically significant differences between implants groups. Linear regression models were developed to test the dependence of the study variables by the degree of subcrestal surgical implant placement. Significance level was set at P0.05.One hundred and thirty-seven implants were followed for an average period of 31 months. At the surgery, the implants were placed, on average, 2.04 mm (mesial) and 1.86 mm (distal) subcrestally. Eighty implants were placed less than 2 mm under the crest (average 1.28 mm), while fifty-seven implants were placed more than 2 mm under the crestal bone (average 2.97 mm). At the prosthetic loading (t1), the average crestal bone level was 1.11 mm, 0.79 mm in Shallow group and 1.86 mm in Deep group, with statistically significant differences between implant groups (P0.05). At the follow-up visit (t2) the mean crestal bone levels were respectively 0.51 mm and 1.35 mm, with statistically significant differences between implant groups (P0.05). The average peri-implant bone loss between prosthetic loading and control visit (t1àt2) was 0.04 mm in the Group 1 and 0.33 mm in Group 2. The average keratinized mucosa width was 2.16 mm, the average mBI was 0.24 , the average mPI was 0.17 and the average PD was 2.34 mm. Significant difference between groups was observed regarding to keratinized gingival width (Group 1: 1.97 mm; Group 2: 2.41 mm; P0.05) but not for the other clinical parameters. Linear regression models confirmed the dependence of crestal bone levels by the degree of subcrestal placement (P0.05).After two years of observation, the implant of this study have shown minimal peri-implant bone resorption. The greater subcrestal implant placement has resulted in a higher level of the peri-implant bone crest, both after the osseointegration period and after the loading period. Both the study implants groups have shown good health of peri-implant soft tissues.

A case of rehabilitation of an edentulous patient with loss of vertical dimension is presented here. This patient presents with a Class III dental and skeletal malocclusion with an anterior cross-bite. The objective of this case report is to demonstrate that an accurate assessment of vertical dimension is necessary for good rehabilitation. The original vertical dimension was determined by a series of tests including, kinesiographic, electromyographic and transcutaneous electronic neural stimulation (TENS). Subsequently, the lost vertical dimension was re-established orthodontically. These examinations revealed a general hypertonicity of masticatory muscles due to the lost vertical dimension. Additionally, radiographs of the temporomandibular joint showed anteriorly displaced condyles. Following the completion of orthodontic treatment osseointegrated implants were placed to restore the dental arches.

Sander bite jumping appliance (BJA) is a functional appliance used to correct Class II malocclusion in growing patients. The aim of this study was to identify the dento-skeletal effects in patients treated with BJA before growth peak and to compare these effects with the ones obtained in a similar group treated with the Andresen activator (AA). Twenty subjects with class II relationship of the skeletal bases and cervical vertebrae maturation stage 1 or 2 were enrolled in the study and treated with BJA. This group were compared to 14 subjects treated with AA. Cephalometric analyses were carried out using landmarks derived from the analyses of Pancherz, Ricketts, Tweed and Steiner. After treatment with BJA Pg/OLp increase was 7.40±3.81 mm (P0.001); Pg/OLp+Co/OLp significantly heightened from T0 to T1 (T0: 82.20±4.65 mm vs T1: 89.62±4.27, P0.001). Overjet (is/OLp - ii/OLp) significantly decreased from T0 to T1 (T0: 7.40±2.31 mm vs T1: 3.05±1.34 mm, P0.001). Molar relationship improved passing from 1.46±1.68 mm at T0 to -3.56±2.04 mm at T1 (P0.001). No statistically significant differences were found between BJA and AA groups at T0 and T1. BJA treatment determined a Class II malocclusion correction in all patients. The correction of molar relationship was mainly due to the increase in mandibular length; the correction of the overjet was due to the increase in mandibular length, to the slight pro-inclination of the lower incisors and the mild retro-inclination of the upper incisors. No significant differences were found in effectiveness between BJA and AA.

Silk fibroin hydrogels prepared either by treating a 2% (w/v) silk fibroin aqeuous solution at 4 degrees C (thermgel) or by adding 30% (v/v) of glycerol (glygel), were characterized by using Environmental Scanning Electron Microscopy (ESEM), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Thermogravimetrical Analysis (TGA) and molecular weight determination. The preparation procedure affected morphology and molecular weight of hydrogels, with no or negligible differences being displayed by FT-IR and DSC analyses. While thermgel presented a well uniform porous structure, the morphology of glygel appeared to be non-porous and heterogeneous. Glygel presented lower water content and lower degradation temperatures, associated with the presence of glycerol but likely also to less-organized protein structures. Cytoxicity tests with human osteoblast-like cells indicated that both gels were not cytoxic, while cell cultures pointed out a faster cell proliferation on glygel and a higher cell activation and differentiation on thermgel. These gels could be used as scaffolds able to promote in situ bone regeneration.