CAD/CAM Titanium Meshes for GBR: A Case Series with Preliminary Histologic Analysis.

Titanium has been proposed as a mesh material for guided bone regeneration (GBR) since the 1990s. To overcome difficulties in shaping and adapting meshes to the defect, digital techniques were introduced to digitally print meshes capable of fitting the bone perfectly, reproduced through the patient's CT scan. Five patients were included in this case series, and their CBCT data were acquired and sent to the producer of the titanium meshes. 3D regenerative surgery was performed with titanium meshes and a mix of demineralized bovine bone matrix (DBBM) and autogenous bone (1:1 ratio). Radiographic measures were evaluated on paraxial sections of the CBCT through a dedicated software. When possible, regenerated bone samples were obtained at implant insertion. Four out of five regenerated areas healed without local or systemic complications. One mesh was removed after 2 months and 2 weeks due to exposure. The mean vertical bone gain was 4.3 ± 1.5 mm (range: 2.5 to 7 mm). Two histologic samples were obtained. In sample 1, bone tissue area and graft material area were 44.4% and 12.5%, respectively; in sample 2, the same parameters were 15.6% and 16.9%, respectively.

CAD-CAM Titanium Meshes for GBR: A Case Series with Preliminary Histological Analysis.

Titanium has been proposed as a mesh material for GBR since the nineties. To overcome difficulties in shaping and adaptation to the defect, digital elaboration techniques were introduced to digitally print meshes capable of fitting the bone perfectly, reproduced through the CT scan of the patient. Five patients were included in this case series. CBCT data of patients were acquired and sent to the producer of the titanium mesh. 3-dimension regenerative surgery was performed with titanium meshes and a mix of Demineralized Bovine Bone Matrix (DBBM) and Autologous bone (1:1 ratio). Radiographic measures were evaluated on paraxial sections of the CBCT through a dedicated software. When possible, regenerated bone samples were obtained at implant insertion time. Four out of five regenerated areas healed without local and systemic complications. One mesh was removed after two months and two weeks because of exposition. Mean vertical bone gain was 4.3 ± 1.5 mm (range 2.5 - 7 mm). Two histologic samples were obtained. In sample n.1, Bone Tissue Area and Graft Material Area were respectively 44.4% and 12.5%. In sample n.2, the same parameters were 15.6% and 16.9% respectively.

Implants Placed with the All-On-4 Technique: A Radiographic Retrospective Study on 156 Implants with a 5- to 14-Year Follow-up.

The aim of this retrospective study was to evaluate the performance of implants placed with the All-on-4 technique after a mean time in function of 9 years. A total of 34 patients with 156 implants were selected for this study: 18 patients underwent tooth extraction on the day of implant placement (Group D), and 16 patients were already edentulous (Group E). A periapical radiograph was taken at a mean follow-up of 9 years (range: 5 to 14 years). Success and survival rates and the prevalence of peri-implantitis were calculated. Statistical analysis was used to assess comparisons between groups. After a mean follow-up of 9 years, the cumulative survival rate was 97.4% and the success rate was 77.4%. The difference between the initial and final radiographs resulted in a mean marginal bone loss (MBL) of 1.3 ± 1.06 mm (range: 0.1 to 5.3 mm). No differences were seen between Groups D and E. Peri-implantitis affected 15 implants (9.6%) in 9 patients (26.5%). This study shows that the All-on-4 technique is a reliable treatment method for both edentulous patients and patients requiring tooth extractions, with results maintained over a long follow-up period. The present MBL results are similar to those around implants in other rehabilitation types.

Biofilm Formation on Dental Implant Surface Treated by Implantoplasty: An In Situ Study.

Peri-implantitis is a biofilm-related disease whose characteristics are peri-implant tissues inflammation and bone resorption. Some clinical trials report beneficial effects after implantoplasty, namely the surgical smoothening of the implant surface, but there is a lack of data about the development of the bacterial biofilm on those smoothened surfaces. The aim of this study is to evaluate how implantoplasty influences biofilm formation. Three implants with moderately rough surfaces (control) and three implants treated with implantoplasty (test) were set on a tray reproducing the supra- and sub-gingival environment. One volunteer wore this tray for five days. Every 24 h, plaque coverage was measured and, at the end of the period of observartion, the implant surfaces were analyzed using scanning electron microscopy and confocal laser scanning microscopy. The proportion of implant surface covered with plaque was 65% (SD = 7.07) of the control implants and 16% (SD = 0) of the test implants. Untreated surfaces showed mature, complex biofilm structures with wide morphological diversity, and treated surfaces did not show the formation of mature biofilm structures. This study supports the efficacy of implantoplasty in reducing plaque adhesion and influencing biofilm formation. These results can be considered a preliminary proof of concept, but they may encourage further studies about the effects of implantoplasty on biofilm formation.

Laser microtextured titanium implant surfaces reduce in vitro and in situ oral biofilm formation.

INTRODUCTION: Micro- or nano-topography can both provide antimicrobial properties and improve osseointegration of dental implant titanium surfaces. Laser treatment is one of the best surface microtexturing techniques. The aim of this study was to evaluate in vitro and in situ biofilm formation on a laser-treated titanium surface, comparing it with two conventional surfaces, machined and grit-blasted. METHODS: For the in vitro experiment, an oral microcosm biofilm model was developed on the surface of titanium disks and reference human enamel using a bioreactor for 48 h. For the in situ experiment, titanium implants with laser-treated, machined and grit-blasted surfaces were mounted on intraoral trays and worn by ten volunteers for 48 h. Biofilm formation was quantitatively evaluated, and surfaces were analyzed using confocal laser scanning microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. RESULTS­IN VITRO STUDY: Biofilm structures with a prevalence of viable cells covered most of the machined, grit-blasted and human enamel surfaces, whereas less dense biofilm structures with non-confluent microcolonies were observed on the laser-treated titanium. Laser-treated titanium showed the lowest biofilm formation, where microorganisms colonized the edges of the laser-created pits, with very few or no biofilm formation observed inside the pits. RESULTS­IN SITU STUDY: The biofilm formation pattern observed was similar to that in the in vitro experiment. Confocal laser scanning microscopy showed complete coverage of the implant threads, with mostly viable cells in grit-blasted and machined specimens. Unexpectedly, laser-treated specimens showed few dead microbial cells colonizing the bottom of the threads, while an intense colonization was found on the threading sides. CONCLUSION: This data suggests that laser-created microtopography can reduce biofilm formation, with a maximum effect when the surface is blasted orthogonally by the laser beam. In this sense the orientation of the laser beam seems to be relevant for the biological interaction with biofilms.

Retrospective analysis of the prevalence of peri-implant diseases in non-smoking patients rehabilitated with a fixed full-arch restoration, supported by two mesial axial and two distal tilted implants.

BACKGROUND: The objective of the study was to evaluate the prevalence of peri-implant mucositis and peri-implantitis in non-smoking patients rehabilitated with a fixed prosthesis supported by two axial and two tilted implants. METHODS: Forty-three patients with a total of 49 rehabilitations were included in the study. Each patient was included in a follow-up schedule consisting in a visit every six months during the first two years and every year thereafter in which professional oral hygiene was performed and data about bleeding on probing, probing depth and bone resorption were collected. Diagnoses of peri-implant mucositis (Bleeding Index>1) and peri-implantitis (Bleeding Index>1, probing depth >4, bone resorption radiographically detectable) were made. RESULTS: The considered observational time was from 1 to 10 years. The prevalence of peri-implant mucositis detected ranged from 0 to 12.2% of patients (8.7% of implants), while that of peri-implantitis varied between 0 and 9.1% of patients (6.8% of implants) in the different follow-up considered. CONCLUSIONS: The prevalence of peri-implant mucositis and peri-implantitis was lower than in most of the studies in literature suggesting the feasibility of this kind of rehabilitation, in combination with a strict hygiene recall protocol, in preventing the onset of these diseases.

Evaluation of clinical outcomes and bone loss around titanium implants with oxidized surface: six-year follow-up results from a prospective case series study.

PURPOSE: The aim of this prospective study was to assess long-term clinical outcomes and peri-implant bone level changes around oxidized implants supporting partial fixed rehabilitations. MATERIALS AND METHODS: Twenty-two partially edentulous patients were included in the study. A total of 33 fixed rehabilitations were placed, supported by 54 titanium implants with oxidized microtextured surface. Prostheses were delivered after 3 and 6 months of implant placement in the mandible and maxilla, respectively. Patients were scheduled for follow-up at 6 and 12 months and then yearly. At each follow-up, plaque level and bleeding scores were assessed and periapical radiographs were taken. The main outcomes were prosthesis success, implant survival, implant success, and marginal bone level change. RESULTS: Three patients were excluded from the study because they did not attend the 1-year follow-up. Nineteen patients, accounting for 49 implants, were followed for at least 6 years after prosthesis delivery. The mean follow-up duration was 81.8 months (range 75-96 months). One mandibular single-tooth implant failed after 1 year in a smoker woman. Cumulative implant survival and success at 6 years were 98.0% and 95.9%, respectively. Prosthesis success was 96.7%. The mean peri-implant bone loss at 6 years was 0.76 ± 0.47 mm. Not significantly (p = .75) greater bone loss was found in the maxilla (0.78 ± 0.14 mm, n = 19) as compared with the mandible (0.74 ± 0.59 mm, n = 30). In the maxilla, bone loss was significantly greater around implants supporting partial prostheses as compared with single-tooth implants (p = .03). Full patient satisfaction was reported. CONCLUSION: Implants with oxidized microtextured surface may achieve excellent long-term clinical outcomes in the rehabilitation of partial edentulism.

Tilted implants for full-arch rehabilitations in completely edentulous maxilla: a retrospective study.

Purpose. The aims of this study were to assess the treatment outcome of immediately loaded full-arch fixed bridges anchored to both tilted and axially placed implants in the edentulous maxilla and to evaluate the incidence of biological and prosthetic complications. Materials and Methods. Thirty-four patients (18 women and 16 men) were included in the study. Each patient received a maxillary full-arch fixed bridge supported by two axial implants and two distal tilted implants. A total of 136 implants were inserted. Loading was applied within 48 hours of surgery and definitive restorations were placed 4 to 6 months later. Patients were scheduled for followup at 6, 12, 18, and 24 months and annually up to 5 years. At each followup plaque level and bleeding scores were assessed and every complication was recorded. Results. The overall follow-up range was 12 to 73 months (mean 38.8 months). No implant failures were recorded to date, leading to a cumulative implant survival rate of 100%. Biological complications were recorded such as alveolar mucositis (11.8% patients), peri-implantitis (5.9% patients), and temporomandibular joint pain (5.9% patients). The most common prosthetic complications were the fracture or detachment of one or multiple acrylic teeth in both the temporary (20.6% patients) and definitive (17.7% patients) prosthesis and the minor acrylic fractures in the temporary (14.7% patients) and definitive (2.9% patients) prosthesis. Hygienic complications occurred in 38.2% patients. No patients' dissatisfactions were recorded. Conclusions. The high cumulative implant survival rate indicates that this technique could be considered a viable treatment option. An effective recall program is important to early intercept and correct prosthetic and biologic complications in order to avoid implant and prosthetic failures.