Clinical Outcome of Fully Digital Workflow for Single-Implant-Supported Crowns: A Retrospective Clinical Study.

A digital workflow by means of intraoral scanners and computer tomography has been used in dental implantology, allowing clinicians to be potentially more accurate and precise. Computer-Aided Design and Computer-Aided Manufacturing (CAD-CAM) and 3D models facilitate the process from treatment planning to the surgical procedure, up to the implant placement and final prosthesis. The aim of the present retrospective study was to evaluate a fully digital workflow for single-tooth implant rehabilitation. A total of 19 patients (22 implants) were included in the present study, with a mean follow-up time of 2 years. A fully digital workflow was performed on each patient through the planning, design and printing of a surgical guide, following a digital impression made with an intraoral scanner, computer-tomography-guided implant placement and, finally, with the delivery of a CAD-CAM crown. The two-year follow-up results were satisfactory in terms of the aesthetic yield and precision of the prosthesis. In single-implant-supported restorations, due to digital protocols and digital planning, a reduced number of clinical sessions was registered and the treatment plan results were more predictable. Future studies are needed to understand the application of fully digital protocols in cases of partially or totally edentulous patients.

Electrolytic Cleaning and Regenerative Therapy of Peri-implantitis in the Esthetic Area: A Case Report.

Implantology represents the gold standard in oral rehabilitation. Unfortunately, a new pathology begins to show itself to clinicians that no longer affects only and solely the supporting tissues of the tooth but also dental implants and peri-implantitis. In this study, we present a case report regarding a tissue regeneration maneuver involving dental implants. The clinical and radiographic results are encouraging, regarding the use of these techniques on implant surfaces. Surely, the advent of new biomaterials and surgical techniques will make this practice safe and predictable.

Guided implant surgery and sinus lift in severely resorbed maxillae: A retrospective clinical study with up to 10 years of follow-up.

OBJECTIVES: In the posterior maxilla, due to the presence of maxillary sinus, residual bone height lower than 3mm is a critical factor that can affect implant stability and survival. The use of guided surgery may facilitate the surgical procedures and the implant insertion in case of severely resorbed maxillae. Moreover, it may have beneficial effects on the long-term survival and success of implant-supported restorations. This study aimed to evaluate implant supported restorations on severely resorbed maxilla (<3 mm) after sinus lift with collagenated xenograft and guided surgery. METHODS: Forty-three patients with need for implant rehabilitation and residual bone height between 1 and 3 mm were recruited. Surgical and prosthetical aspects were planned following digital approach with the use of Realguide 5.0 (3diemme, Varese, Italy). Lateral window sinus lift was performed and implants were placed simultaneously to the augmentation procedure with a tooth-supported pilot drill surgical template. A pre-hydrated collagenated porcine bone matrix was adopted as regenerative material. Computer-aided-design/computer-aided-manufacturing (CAD/CAM) restorations were delivered after six months of healing. Milled titanium chamfer abutments with CAD/CAM crowns were used. Bone height at implant site level was measured using an image software analysis applied to the pre- and post-surgical radiographs and at the follow-up. Biological and technical complications were recorded during all the follow-up periods. RESULTS: Fifty-four sinus were treated. After a mean follow-up time of 5.11 years (SD: 2.47), no implants were lost nor showed signs of disease. The mean pristine bone height was 2.07 mm (SD: 075). At the final evaluation the augmented sinus height was 12.83 mm (SD: 1.23). Two cases experienced minor perforation of the membrane, while five patients developed minimal post-operative complications, completely resolved with pharmacologic therapy. No mid-term biological complications were experienced by the patients. No cases experienced peri-implant mucositis and peri-implantitis during the whole follow-up period. Four patients (7.4%) faced an unscrewing of the prosthesis. CONCLUSIONS: The present study showed the efficacy in the mid-term of the digital planning and the guided surgery in restoring severely resorbed posterior maxilla with dental implants. CLINICAL SIGNIFICANCE: This paper underlines the high potential of the digital approach in the mid-term to implant rehabilitation of severely resorbed maxilla simultaneously with sinus lift.

Microscopic Characterization of Bioactivate Implant Surfaces: Increasing Wettability Using Salts and Dry Technology.

The surface topography of dental implants plays an important role in cell-surface interaction promoting cell adhesion, proliferation and differentiation influencing osseointegration. A hydrophilic implant leads to the absorption of water molecules and subsequently promotes the adhesion of cells to the implant binding protein. Dried salts on the implant surfaces allow one to store the implant surfaces in a dry environment while preserving their hydrophilic characteristics. This process has been identified as "dry technology". The aim of the present study is to describe from a micrometric and nanometric point of view the characteristics of this new bioactivated surface obtained using salts dried on the surface. Topographic analysis, energy-dispersive X-ray spectroscopy, and contact angle characterization were performed on the samples of a sandblasted and dual acid-etched surface (ABT), a nanosurface (Nano) deriving from the former but with the adding of salts air dried and a nanosurface with salts dissolved with distilled water (Nano H2O). The analysis revealed promising results for nanostructured surfaces with increased wettability and a more articulated surface nanotopography than the traditional ABT surface. In conclusion, this study validates a new promising ultra-hydrophilic nano surface obtained by sandblasting, double acid etching and surface salt deposition using dry technology.

The Role of Platelet-Rich Fibrin (PRF) in the Prevention of Medication-Related Osteonecrosis of the Jaw (MRONJ).

Dentoalveolar surgery is probably the major risk factor for MRONJ and for other complications following a tooth extraction, especially in patients affected by systemic diseases. The aim of this retrospective study is to evaluate whether a PRF plug inserted in the post extraction socket can prevent the onset of MRONJ. The patients were divided into two groups according to the surgical protocol that included the insertion or not of the PRF following the extraction and all the anamnestic, and clinical data were analyzed. In the control group, 5 patients developed MRONJ (19.23%) while in the study group, any case of MRONJ was reported. In the control group, patients who developed MRONJ had a CTX with less than 100 pg/mL (5 high-risk patients, Spearman's rank r = .547, p < .001). The use of platelet concentrates in patients with high risk of MRONJ is a user-friendly technique with an excellent cost-benefit ratio in oral surgery.

Retrograde peri-implantitis associated with residual cysts: 3 Case reports.

BACKGROUND AND OVERVIEW: The authors describe 3 cases of retrograde peri-implantitis associated with residual cysts and their successful surgical and regenerative management. Implants were originally placed with both immediate and delayed protocols. CASE DESCRIPTION: Three patients sought treatment at the authors' specialist private practices with the chief symptoms of pain and swelling in association with implant-retained restorations. Clinical, radiographic, and histopathologic findings supported the diagnoses of infected residual cysts. The lesions were enucleated in toto, the implant surfaces were decontaminated, and bone regeneration procedures were carried out. Long-term recall visits, ranging from 3 through 10 years, confirmed successful retention of all implants treated accordingly. CONCLUSIONS AND PRACTICAL IMPLICATIONS: The authors describe an unusual clinical manifestation and emphasize the role of local procedures during implant placement in areas compromised with infection, cysts, or both and the importance of long-term recall visits.

Guided Bone Regeneration with Nonresorbable Membranes in the Rehabilitation of Partially Edentulous Atrophic Arches: A Retrospective Study on 122 Implants with a 3- to 7-Year Follow-up.

The aim of this retrospective study was to evaluate clinical and radiographic outcomes of guided bone regeneration (GBR) procedures in the rehabilitation of partially edentulous atrophic arches. A total of 58 patients were included with a follow-up of 3 to 7 years after loading. Data seem to indicate that GBR with nonresorbable membranes can be a good clinical choice and suggest that it could be used to vertically reconstruct no more than 6 mm of bone in the posterior mandible. However, this technique remains difficult and requires expert surgeons.

A prospective case series on surgical treatment of circumferential and semi-circumferential defects due to peri-implantitis.

Different surgical treatment strategies for peri-implantitis with the use of graft material and membranes have been suggested without any longitudinal remarkable success rate. The present preliminary study was aimed to analyze a new clinical approach based on the disinfection of the implant connection, the disinfection of the implant surface and GBR approach in the treatment of circumferential and semi-circumferential bony defect resulting from peri-implantitis. Six consecutive patients were selected for the present study. After removal of factors that could potentially influence peri-implant pathology, the prosthetic rehabilitation was always removed and a full thickness flap was elevated to allow access to the peri-implant defect and the exposed implant surface. Once the defect was degranulated and the implant surface cleaned, a mixture (50:50) of autogenous bone and allograft was used. Guided bone regeneration technique using membranes was adopted and the flaps were closed for a submerged healing. Six months thereafter, a new re-opening procedure was performed and cleaned superstructures and crowns were repositioned. Patients were followed for one year thereafter and recalled for a customized oral hygiene every three months. Radiological and periodontal analysis was performed before surgery and every six months. The studied procedure was associated with a pronounced increase in REC and CAL with stable peri-implant conditions at 6 and 12 months. PI, BOP and PD values were significantly reduced both at 6 and 12 months. At 12 months, a mean PD gain of 4.5 mm and a bone loss reduction of 5.1 mm was obtained. Within the limitation of the present preliminary study, the proposed technique might represent a promising result for treatment of circumferential and semi-circumferential bone defects around implants affected by peri-implantitis.

A prospective case series on surgical treatment of circumferential and semi-circumferential defects due to peri-implantitis

Abstract Different surgical treatment strategies for peri-implantitis with the use of graft material and membranes have been suggested without any longitudinal remarkable success rate. The present preliminary study was aimed to analyze a new clinical approach based on the disinfection of the implant connection, the disinfection of the implant surface and GBR approach in the treatment of circumferential and semi-circumferential bony defect resulting from peri-implantitis. Six consecutive patients were selected for the present study. After removal of factors that could potentially influence peri-implant pathology, the prosthetic rehabilitation was always removed and a full thickness flap was elevated to allow access to the peri-implant defect and the exposed implant surface. Once the defect was degranulated and the implant surface cleaned, a mixture (50:50) of autogenous bone and allograft was used. Guided bone regeneration technique using membranes was adopted and the flaps were closed for a submerged healing. Six months thereafter, a new re-opening procedure was performed and cleaned superstructures and crowns were repositioned. Patients were followed for one year thereafter and recalled for a customized oral hygiene every three months. Radiological and periodontal analysis was performed before surgery and every six months. The studied procedure was associated with a pronounced increase in REC and CAL with stable peri-implant conditions at 6 and 12 months. PI, BOP and PD values were significantly reduced both at 6 and 12 months. At 12 months, a mean PD gain of 4.5 mm and a bone loss reduction of 5.1 mm was obtained. Within the limitation of the present preliminary study, the proposed technique might represent a promising result for treatment of circumferential and semi-circumferential bone defects around implants affected by peri-implantitis.

Posterior atrophic jaws rehabilitated with prostheses supported by 6 mm long × 4 mm wide implants or by longer implants in augmented bone. 3-year post-loading results from a randomised controlled trial.

PURPOSE: To evaluate whether 6 mm long × 4 mm wide dental implants could be an alternative to implants of at least 10 mm long placed in bone augmented with bone substitutes in posterior atrophic jaws. MATERIALS AND METHODS: A total of 20 patients with bilateral atrophic mandibles, and 20 patients with bilateral atrophic maxillae, having 5 mm to 7 mm of bone height below the maxillary sinus or 6 mm to 8 mm above the mandibular canal, had their side of the jaws randomly allocated according to a split-mouth design. They were allocated to receive one to three 6 mm long × 4 mm wide implants, or implants of at least 10 mm long in augmented bone by two different surgeons at different centres. Mandibles were vertically augmented with interpositional equine bone blocks and resorbable barriers, and implants were placed 3 months later. Maxillary sinuses were augmented with particulated porcine bone via a lateral window and implants were placed simultaneously. After 4 months, all implants were submerged and loaded with provisional prostheses. Four months later, definitive prostheses were delivered. Outcome measures were prosthesis and implant failures, any complication and radiographic peri-implant marginal bone level changes. RESULTS: Five patients (three treated in mandibles and two in maxillae) dropped out before the 3-year post-loading follow-up. Two short maxillary implants affected by peri-implantitis failed together with their prosthesis vs three mandibular prostheses that could not be placed on implants at least 10 mm long due to graft failures; one was associated with the loss of three implants because of infection. There were no statistically significant differences in implant (difference in proportions = 0.000; 95% CI: -0.140 to 0.140; P = 1.000) and prosthesis failures (difference in proportions = 0.057; 95% CI: -0.094 to 0.216; P = 0.625). In total, 18 complications occurred in 13 patients at augmented sites vs four complications in three patients with 6 mm long implants. Significantly more complications occurred at grafted sites in mandibles (difference in proportions = 0.353; 95% CI: 0.005 to 0.616; P = 0.031), but not in maxillae (difference in proportions = 0.222; 95% CI: -0.071 to 0.486; P = 0.219). In mandibles, patients with 6 mm long implants lost an average of 1.25 mm of peri-implant bone at 3 years vs 1.54 mm in patients with implants of at least 10 mm long. The difference was statistically significant (mean difference = 0.29 mm; 95% CI: 0.08 to 0.51 mm; P = 0.010). In maxillas, patients with 6 mm-long implants lost an average of 1.28 mm of peri-implant bone at 3 years vs 1.50 mm in patients with implants of at least 10 mm long. The difference was statistically significant (mean difference = 0.22 mm; 95% CI: 0.08 to 0.35 mm; P = 0.003). CONCLUSIONS: Results at 3 years after loading indicate that 6 mm long implants with a conventional diameter of 4 mm achieved similar, if not better, results than longer implants placed in augmented bone. Short implants might be a preferable choice to bone augmentation, especially in posterior mandibles, since the treatment is faster, cheaper and associated with less morbidity. However, data obtained 5 to 10 years after loading are necessary before making reliable recommendations.

Displacement of a dental implant in the mandible body: an unusual case report.

PURPOSE: To present a case of a woman referred for the management of displacement of one implant in her right posterior mandible that had occurred three days previously. MATERIALS AND METHODS: After implant placement, the practitioner was no longer able to detect the implant and inserted a second one at the same site without taking a control radiograph. At the end of surgery, when a radiograph was finally taken, the first implant appeared displaced into the mandible body. The patient suffered total paresthesia on the right lower lip and chin. A flap was raised and bone osteotomies were performed on the lateral side of the mandible to create a rectangular cortical bone window that was removed. The implant was stuck by the second implant placed coronally, and only after unscrewing this second implant was it possible to remove the first one. RESULTS: After 18 months, the patient recovered full sensitivity. CONCLUSIONS: In cases of implant displacement, it is always recommended that appropriate radiographs are performed to visualise where the implants could have been displaced in order to avoid more serious consequences.

4 mm long vs longer implants in augmented bone in posterior atrophic jaws: 1-year post-loading results from a multicentre randomised controlled trial.

PURPOSE: To evaluate whether 4.0 mm short dental implants could be an alternative to augmentation with xenographs in the maxilla and placement of at least 10.0 mm long implants in posterior atrophic jaws. MATERIALS AND METHODS: A group of 40 patients with atrophic posterior (premolar and molar areas) mandibles with 5.0 mm to 6.0 mm bone height above the mandibular canal and 40 patients with atrophic maxillas having 4.0 mm to 5.0 mm below the maxillary sinus, were randomised according to a parallel group design to receive between one and three 4.0 mm long implants or one to three implants of at least 10.0 mm long in augmented bone, at two centres. All implants had a diameter of 4.0 mm or 4.5 mm. Mandibles were vertically augmented with inter-positional equine bone blocks and resorbable barriers. Implants were placed 4 months after the inter-positional grafting. Maxillary sinuses were augmented with particulated porcine bone via a lateral window covered with resorbable barriers, and implants were placed simultaneously. Implants were not submerged and were loaded after 4 months with provisional screw-retained reinforced acrylic restorations replaced after another 4 months by definitive screw-retained metal-composite prostheses. Patients were followed up to 1 year post-loading. Outcome measures were: prosthesis and implant failures, any complication, and peri-implant marginal bone level changes. RESULTS: Three patients dropped out; one from the maxillary augmented group, one from the mandibular augmented group, and one from the maxillary short implant group. In six augmented mandibles (30%) it was not possible to place implants of at least 10.0 mm, so shorter implants were placed instead. In mandibles, one implant from the augmented group failed vs two 4.0 mm implants in two patients from the short implant group. In maxillae, three short implants failed in two patients vs seven long implants in four patients (two long implants and one short implant dropped into the maxillary sinus). Two prostheses on short implants (one mandibular and one maxillary) were placed at a later stage because of implant failures, vs six prostheses (one mandibular and five maxillary) at augmented sites (one mandibular prosthesis not delivered, three maxillary prostheses delivered with delays, one not delivered, and one failed) at augmented sites. In particular, three patients in the augmented group (one mandible and two maxillae) were not wearing a prosthesis. There were no statistically significant differences in implant failures (P (chi-square test) = 0.693; difference in proportion = 0.03; CI 95% -0.11 to 0.17) or prostheses failures (P (chi-square test) = 0.126; difference in proportion = 0.10; CI 95% -0.03 to 0.24). At mandibular sites, nine augmented patients were affected by complications vs two patients treated with short implants (P (chi-square test) = 0.01; difference in proportion = 0.37; CI 95% 0.11 to 0.63), the difference being statistically significant. No significant differences were found for maxillae: nine sinus-lifted patients vs four short implant patients were affected by complications (P (chi-square test) = 0.091; difference in proportion = 0.25; CI 95% -0.03 to 0.53). At 1-year post-loading, average peri-implant bone loss was 0.51 mm at 4 mm long mandibular implants, 0.77 mm at 10 mm or longer mandibular implants, 0.63 mm at short maxillary implants and 0.72 mm at long maxillary implants. The difference was statistically significant in mandibles (mean difference -0.26 mm, 95% CI -0.39 to -0.13, P (ANCOVA) < 0.001), but not in maxillae (mean difference -0.09 mm, 95% CI -0.24 to 0.05, P (ANCOVA) = 0.196). CONCLUSIONS: One year after loading 4.0 mm long implants achieved similar results, if not better, than longer implants in augmented jaws, but were affected by fewer complications. Short implants might be a preferable choice over bone augmentation, especially in mandibles, since the treatment is less invasive, faster, cheaper, and associated with less morbidity. However, 5 to 10 years post-loading data are necessary before making reliable recommendations.

Posterior atrophic jaws rehabilitated with prostheses supported by 5 × 5 mm implants with a nanostructured calcium-incorporated titanium surface or by longer implants in augmented bone. 3-year results from a randomised controlled trial.

PURPOSE: To evaluate whether 5.0 × 5.0 mm dental implants with a novel nanostructured calcium-incorporated titanium surface could be an alternative to implants of at least 10.0 mm long placed in bone augmented with bone substitutes in posterior atrophic jaws. MATERIALS AND METHODS: Forty patients with atrophic posterior (premolar and molar areas) mandibles with 5.0 mm to 7.0 mm bone height above the mandibular canal, and 40 patients with atrophic maxillas with 4.0 mm to 6.0 mm below the maxillary sinus, were randomised according to a parallel group design to receive between one and three 5.0 mm implants or one to three at least 10.0 mm-long implants in augmented bone at two centres. All implants had a diameter of 5.0 mm. Mandibles were vertically augmented with interpositional bovine bone blocks covered with resorbable barriers. Implants were placed after 4 months. Maxillary sinuses were augmented with particulated porcine bone via a lateral window covered with resorbable barriers, and implants were placed simultaneously. All implants were submerged and loaded after 4 months with provisional prostheses. Four months later, definitive screw-retained or provisionally cement metal-ceramic or zirconia prostheses were delivered. Patients were followed to 3 years post-loading and the outcome measures were: prosthesis and implant failures, any complication, and peri-implant marginal bone level changes. RESULTS: Seven patients dropped out before the 3-year evaluation (two short mandibles, one short maxilla, two augmented mandibles and two augmented maxillae). In mandibles, two grafted patients were not prosthetically rehabilitated because of multiple complications and two implants failed in the same patient (the second was a replacement implant) vs one patient who lost a short implant and crown 2 years after loading. In maxillas one short implant failed with its provisional crown 3 months post-loading. There were no statistically significant differences in prostheses (difference in proportion = 0.001; 95% CI: -0.12 to 0.13; P = 1.000) and implant failures (difference in proportion = 0.00; 95% CI: -0.13 to 0.13; P = 1.000) up to 3 years after loading. Significantly, more complications occurred at mandibular grafted sites: 17 augmented patients were affected by complications vs eight patients treated with short implants in mandibles (difference in proportion = 0.43; 95% CI: 0.13 to 0.64; P = 0.008). In the maxilla, six sinus-lifted patients vs two patients treated with short implants were affected by complications; the difference not being statistically significant (difference in proportion = 0.21; 95% CI: -0.05 to 0.45; P = 0.232). Patients with mandibular short implants lost on average 1.10 mm of peri-implant bone at 3 years and patients with 10.0 mm or longer mandibular implants lost 1.39 mm. Patients with maxillary short implants lost on average 1.04 mm of peri-implant bone at 3 years and patients with 10 mm or longer maxillary implants lost 1.43 mm. Longer implants showed a greater bone loss up to 3 years after loading than short implants both in maxillae (mean difference: -0.39 mm; 95% CI: -0.70 to -0.07 mm; P = 0.017) and in mandibles (mean difference: -0.29 mm; 95% CI: -0.53 to -0.05 mm; P = 0.020). CONCLUSIONS: Three years after loading, 5.0 mm × 5.0 mm implants achieved similar results than longer implants placed in augmented bone. Short implants might be a preferable choice to bone augmentation especially in posterior mandibles since the treatment is faster, cheaper and associated with less morbidity. However, 5- to 10-year post-loading data are necessary before making reliable recommendations.

Immediate, early (6 weeks) and delayed loading (3 months) of single, partial and full fixed implant supported prostheses: 1-year post-loading data from a multicentre randomised controlled trial.

PURPOSE: To compare the clinical outcome of single, partial and complete fixed implant supported prostheses immediately loaded (within 48 h), early loaded at 6 weeks, and conventionally loaded at 3 months (delayed loading). MATERIALS AND METHODS: A total of 54 patients (18 requiring single implants, 18 partial fixed prostheses, and 18 total fixed cross-arch prostheses) were randomised in equal numbers at two private practices to immediate loading (18 patients), early loading (18 patients), and conventional loading (18 patients) according to a parallel group design with three arms. To be immediately or early loaded, implants had to be inserted with a torque superior to 40 Ncm. Implants were initially loaded with provisional prostheses, replaced after 4 months by definitive ones. Outcome measures were prosthesis and implant failures, complications and peri-implant marginal bone levels. RESULTS: Two conventionally loaded patients rehabilitated with cross-arch fixed total prostheses dropped-out up to 1 year post-loading. No implant or prosthesis failed and three complications occurred, one in each loading group. Peri-implant marginal bone loss was 0.19 ± 0.44 mm at immediately loaded implants, 0.18 ± 0.66 mm at early loaded implants and 0.25 ± 0.28 mm at conventional loaded implants. There were no statistically significant differences in complications (P = 1.000) and bone loss (P = 0.806) between the three loading strategies. CONCLUSIONS: All loading strategies were highly successful and no differences could be observed for implant survival and complications when loading implants immediately, early or conventionally.