Vertical ridge augmentation with Ti-reinforced dense polytetrafluoroethylene (d-PTFE) membranes or Ti-meshes and collagen membranes: 3-year results of a randomized clinical trial

BackgroundThe present study aimed to evaluate hard and soft tissue parameters around implants placed in augmented posterior mandible, comparing Ti-reinforced d-PTFE membranes with Ti-meshes covered with collagen membranes, after 3 years of follow-up. Materials and MethodsForty eligible patients were randomly assigned to group A (Ti-reinforced d-PTFE membrane) or group B (mesh covered with collagen membrane) for vertical ridge augmentation (VRA) and simultaneous implants. Implants were evaluated using specific peri-implant parameters for bone and soft tissues: probing pocket depth (PPD), modified plaque index (mPI), bleeding on probing (BoP), modified gingival index (mGI), thickness of keratinized tissue (tKT), width of keratinized tissue (wKT), fornix depth (FD), peri-implant bone level (PBL), interproximal bone peaks (IBP), marginal bone loss (MBL), interproximal bone loss (IBL). ResultsA total of 28 patients with 79 implants were evaluated after 3 years of follow-up. The mean value of MBL was 0.70 mm (group A = 0.73 mm; group B = 0.71 mm), while mean IBL was 0.54 mm (group A = 0.64 mm; group B = 0.40 mm). The treatment with meshes resulted not inferior to PTFE and their clinical results appeared similar. A strong correlation between PBL and IBP was confirmed. Both study groups showed an increase of tKT and wKT values. ConclusionIn the posterior mandible, VRA using both techniques provides stable PBLs up to 3 years. A correct soft tissue management and a strict professional oral hygiene protocol play a crucial role on peri-implant health over time

Dental implants with anti-biofilm properties: A pilot study for developing a new sericin-based coating

Aim: several strategies have been tested in recent years to prevent bacterial colonization of dental implants. Sericin, one of the two main silk proteins, possesses relevant biological activities and also literature reports about its potential antibacterial properties, but results are discordant and not yet definitive. The aim of this study was to evaluate the effectiveness of different experimental protocols in order to obtain a sericin-based coating on medical grade titanium (Ti) able to reduce microbial adhesion to the dental implant surface. Materials and Methods: different strategies for covalent bonding of sericin to Ti were pursued throughout a multi-step procedure on Ti-6Al-4V disks. The surface of grade 5 Ti was initially immersed in NaOH solution to obtain the exposure of functional -OH groups. Two different silanization strategies were then tested using aminopropyltriethoxysilane (APTES). Eventually, the bonding between silanized Ti-6Al-4V and sericin was obtained with two different crosslinking processes: glutaraldehyde (GLU) or carbodiimide/N-Hydroxy-succinimide (EDC/NHS). Micro-morphological and compositional analyses were performed on the samples at each intermediate step to assess the most effective coating strategy able to optimize the silanization and bioconjugation processes. Microbiological tests on the coated Ti-6Al-4V disks were conducted in vitro using a standard biofilm producer strain of Staphylococcus aureus (ATCC 6538) to quantify the inhibition of microbial biofilm formation (anti-biofilm efficacy) at 24 hours. Results: both silanization techniques resulted in a significant increase of silicon (Si) on the Ti-6Al-4V surfaces etched with NaOH. Differences were found between GLU and EDC/NHS bioconjugation strategies in terms of composition, surface micro-morphology and anti-biofilm efficacy. Ti-6Al-4V samples coated with GLU-bound sericin after silanization obtained via vapor phase deposition proved that this technique is the most convenient and effective coating strategy, resulting in a bacterial inhibition of about 53% in respect to the uncoated Ti-6Al-4V disks. Conclusions: The coating with glutaraldehyde-bound sericin after silanization in the vapor phase showed promising bacterial inhibition values with a significant reduction of S. aureus biofilm. Further studies including higher number of replicates and more peri-implant-relevant microorganisms are needed to evaluate the applicability of this experimental protocol to dental implants. View Full-Tex

A comparative retrospective study of immediately-loaded implants in postextraction sites versus healed sites: results after a 6- to 7-year follow-up in the maxilla.

PURPOSE: Immediate loading has become an emerging technique because it has been shown to be a successful, time-saving procedure. Recently, immediate loading has been performed simultaneously with implant placement into fresh extraction sockets; excellent results have been achieved, but few reports are available with a long-term follow-up. The aim of the present study was to evaluate the difference in success rates in the maxilla between postextraction implants and implants placed in healed sites, both of which were immediately loaded, after a long-term follow-up. MATERIALS AND METHODS: Between October 2001 and February 2003, 239 implants were inserted in 81 consecutively operated patients and immediately loaded; 138 implants were placed in fresh postextraction sites (57.7%) and 101 implants were placed in healed sites (42.3%). Two different implant systems were used in this study. Each implant was loaded within 72 hours of placement (60.3% at the time of surgery, 6.3% after 24 hours, 30.1% after 48 hours, and 3.3% after 72 hours). Preestablished success criteria were used to evaluate the success rate of the implants. RESULTS: The mean follow-up was 6.7 years (range: 6.0 to 7.3 years). Only 8 of the 239 implants failed, for an overall success rate of 96.6%. Six of the failed implants were inserted in postextraction sites, and 2 had been placed in healed sites; the success rates were 95.7% and 98.0%, respectively. Statistical analysis revealed no significant differences between postextraction and healed sites. CONCLUSIONS: Immediate loading of immediate postextraction sites results in an implant success rate that is broadly comparable to that seen for implants placed in healed sites. Moreover, this procedure can provide predictable and favorable results in many different clinical conditions and for a long term

A case of rapidly progressive peri-implantitis around a short sintered porous-surfaced implant

The aim of this case report is to show a rapidly progressive form of peri-implantitis around a 7 mm-long sintered porous-surfaced (SPS) implant. It was actually characterized by extremely rapid progression of bone loss, which led to the failure of one implant in about 60 days. Although surgical treatments were attempted to arrest bone resorption, peri-implantitis did not resolve. Short implants are a very useful solution for the management of highly-resorbed posterior areas. That is why patients who rehabilitated with these kinds of implants should adhere to a well-established oral hygiene protocol to prevent bone resorption, which could compromise long-term survival of short implants

Fixed conometric retention with CAD/CAM conic coupling abutments and prefabricated syncone caps: A case series

The conometric retention system was proposed and described as a predictable alternative to retain fixed implant-supported complete dentures and, more recently, to retain fixed partial restorations. Currently available studies describe a technique based on the Ankylos (Dentsply) implant system and stock conic coupling abutments. The purpose of this case series study is therefore to demonstrate the possibility of using Atlantis computer-aided design/ computer-assisted manufacture technology to produce Conus abutments (Dentsply) and using the fixed conometric retention with other implant brands for which appropriate stock conic coupling abutments are not available

Peri-implant bone response around a human hydroxyapatite-coated implant retrieved after a 10-year loading period: a case report.

This case report presents a histologic and histomorphometric evaluation of the peri-implant tissues of a HA-coated implant retrieved due to peri-implantitis after a 10-year loading period. The implant was retrieved with a trephine and treated to obtain thin ground sections. At low-power magnification mostly compact, mature bone with small marrow spaces could be observed at the interface with the implant. The coating was always present in the areas where bone was detected, the bone was always in close contact with the coating, and there was no detachment between the metal and coating or between the coating and bone. Areas of bone remodeling were demonstrated by the presence of many secondary osteons and reversal lines close to the implant surface. The bone-implant contact percentage was 36.3% \ub1 1.2%. The percentage of the implant surface covered by the HA coating without bone, where bone may have detached during retrieval, was 32.6% \ub1 2.8%. This HA-coated implant, continued to demonstrate more than adequate BIC after many years of function and the potential to maintain osseointegration in the long term