Background and Objectives: The aim of this study is to evaluate the efficacy of an autologous dentin graft, via extracted teeth that are processed into bacteria-free particulate dentin in a Smart dentin grinder and then grafted immediately into alveolus post extraction or into bone deficiencies. Materials and Methods: Ten healthy, partially edentulous patients with some teeth in the mandible were recruited in the study. After their own teeth were grinded, particulate teeth were placed in empty sockets and bone defects after teeth extractions. Furthermore, after three, six, 12 and 24 months, core samples using a 3 mm trephine were obtained. Results: At three months, the particles of grinded tooth were immersed inside a new connective tissue with a small new bone formation (16.3 ± 1.98). At six months, we observed small particles of dentin integrated in new immature bone, without inflammation in the soft tissue (41.1 ± 0.76). At twelve months, we observed a high amount of bone formation surrounding tooth particles (54.5 ± 0.24), and at twenty-four months, new bone, a big structure of bone, was observed with dentin particles (59.4 ± 1.23), statistically different when compared it with at three months. Conclusions: A particulate dentin graft should be considered as an alternative material for sockets’ preservation, split technique, and also for sinus lifting. One of the special characteristics after 24 months of evaluation was the high resorption rate and bone replacement without inflammation. This material could be considered as an acceptable biomaterial for different bone defects due to its osteoinductive and osteoconductive properties

Our purpose was to physically characterize the surface, and the subsurface, of a macro- and micro-textured titanium grade 5 dental implant surface obtained by etching only, without sandblasting. The topography, surface roughness, as well as the surface structure and subsurface distribution of elements, were determined by scanning electronic microscopy (SEM), non-contact profilometry, X-ray diffraction (XRD), and a concentration profile performed by Auger electron spectroscopy (AES). The hydrogen concentration in the implants was measured; the ability to generate nanostructures when stored in deionized water was also investigated. Under SEM, the surface resembled a sandblasted and etched titanium surface with its typical macro- and micro-texture; roughness was moderate with average roughness (Sa) 1.29 µm. No titanium hydride was found at the implant surface and no enrichment of any alloying element was identified at the surface and subsurface. Hydrogen concentration was 79 ppm, within the normative tolerance (<130 ppm). After storage in water for 6 months, densely packed finger-like nanostructures were observed. The clinical advantage of this textured titanium alloy surface is that it displays the typical macro- and micro-features of a moderately rough sandblasted and etched (SLA) titanium surface without leaving behind any foreign sandblasting material.

Background: Between adjacent dental implants, an interimplant distance (IID) of at least 3 mm has been recommended to avoid resorbing the interproximal crestal bone. The effect of a 2 mm IID on crestal bone loss has been investigated but the literature is scarce when it comes to an IID of 1 mm. There is a need to document such clinical situations when they occur and elucidate if such a narrow IID is deleterious or not to the interproximal crest. The present case deals with an IID of 1 mm in the premolar area where, for the first time, the fate of an interimplant crest is reported after a 10-year follow-up. Case presentation: A 57-year-old patient attended with 2 hopeless maxillary premolars. The mesio-distal space available for implant rehabilitation was too narrow to receive standard diameter implants and keep an inter-implant distance (IID) of 3 mm as recommended by accepted guidelines. A protocol of immediate implant placement and provisionalization involving 2 implants of Ø 3.5 mm was implemented; placement in the extraction sockets resulted in an IID of 1 mm. After 3 months of healing the final prosthesis was delivered; the patient has been followed for 10 years now. Surprisingly, the findings showed that the interimplant crest was maintained 1.40 mm coronal to the shoulder of the neck of the implants. Bone completely filled the space between the prosthetic concave abutments and the interproximal papilla was closing the embrasure. The literature reports only 2 experimental studies involving a 1 mm IID; both showed that this did not lead to the resorption of the interproximal bone. Conclusions: Unexpectedly, the present case with an IID of 1 mm did not lead to the resorption of the interproximal bone after 10 years. It is speculated that the reason for that is due to the implants displaying an internal conical connection, the platform-switching feature, concave abutments and subcrestal placement. The fate of the interproximal crest of implants placed with an IID of 1 mm lacks scientific evidence. More studies are warranted to elucidate this question in order to propose the best implant treatment in cases displaying a limited mesio-distal space.

The aim of this study was to compare the implant stability and bone resorption and formation of two different extra-short implant designs with different diameter rings placed in a dog´s maxilla. Thirty-six extra-short, 5 mm diameter × 4 mm length (Short DM^®, Bioner Sistemas Implantológicos, Barcelona, Spain), delayed implants were placed in each hemimaxilla of six dogs at the bone crest level. Eighteen implants of each design (wide and narrow ring) were installed. After 8 and 12 weeks of healing, histomorphometric analyses of the specimens were carried out to measure the crestal bone level values and the tissue thickness around the wide and narrow ring implant designs. In the microscopic analysis, less buccal bone resorption was observed in the narrow ring implants with a statistical significance (p < 0.001). For the peri-implant tissue thickness, the distance from the implant shoulder to the external portion of the epithelium was significantly higher for the implants installed with a wide ring with statistical significance (p < 0.001). Our findings suggest that the amount of peri-implant tissues (crestal bone loss) after remodeling over a period of 12 weeks was smaller in the narrow ring extra-short implant installed in the healed maxilla, compared with the wide ring extra-short implants.

Background: Dental implant systems provide standard cylindrical healing abutments of various diameters; however, they do not match the larger shape of the complex emergence profile of the prosthetic crowns. Adaptation of the soft tissues from a circular emergence profile to the one that suits the prosthetic crown involves a simultaneous squeezing and stretching of the gingiva. Often, this translates into local blanching of the gingiva and the prosthodontist must assess that blanching is transient. There is no literature about how much strain exerted by the prosthetic crown is leading or not to gingiva blanching. Aim of this paper is to present a digital workflow that allows measuring, upon prosthesis delivery, how much the strained gingiva is displaced under the crown and leads or not to blanching of the peri-implant soft tissues. Method and Results: The digital workflow involves 3 intra-oral scans (IOS), IOS#1 at completion of the soft tissue healing, IOS#2 at prosthesis delivery, IOS#3 after soft tissue conditioning, and the STL files of the healing cap, the abutment, the implant and the prosthetic crown. The above are superposed and merged following a dedicated protocol that provides access to the distance the delivered crown deforms the strained gingiva. The present case study displayed distinct blanching intensities. Severe blanching was present when the strains applied to the gingiva caused a displacement of 1.3 mm and above; a displacement of 0.9 mm led to moderate blanching. No blanching was observed up to a displacement of 0.6 mm. Conclusion: A digital protocol, involving the superposition and merging of IOSs taken along a defined timeline and STLs of the implant hardware, allowed measuring the displacement distances a prosthetic crown wields upon delivery on the gingiva beneath the prosthesis. Various intensities of gingiva blanching could be related to distinct displacement distances of the healed gingiva that were triggered by attaching a prosthetic crown to the implant neck.

Purpose: To evaluate interproximal bone stability in cases of inter-implant distance (IID) < 3 mm over a follow-up period of up to 10 years, and to assess the agreement between digital and radiographic methods for measuring implant spacing. Materials and methods: This retrospective cohort study included 18 pairs of adjacent implants, featuring platform-switching and internal conical connection, placed with an IID < 3 mm and followed for a mean period of 7.32 ± 2.31 years. IID was determined using three approaches: periapical radiography with simple internal calibration, a composite radiographic calibration incorporating vertical and horizontal distortion factors of both implants, and a digital three-dimensional workflow based on intraoral scanning and STL superimposition. Peri-implant marginal bone levels and mid-interproximal bone height were evaluated relative to the implant–abutment junction (IAJ) and to a reference line connecting adjacent IAJs, respectively. Agreement between measurement methods was assessed using Bland–Altman analysis and intraclass correlation coefficients; equivalence testing was performed using two one-sided tests (TOST). Associations between IID and bone parameters were explored using Spearman correlation. Results: The mean digitally measured IID was 1.81 ± 0.71 mm, with 55.6% of sites presenting an IID < 2 mm. Peri-implant marginal bone levels were coronal to the IAJ in 88.9% (32/36) of sites. Mid-interproximal bone was located 1.97 ± 0.88 mm coronal to the line connecting adjacent IAJs. No statistically significant association was found between IID and peri-implant or interproximal bone levels. IID measurement methods demonstrated a high agreement of ICC = 0.95; nonetheless, simple radiographic calibration tended to underestimate IID. At an equivalence margin of ± 0.1 mm, only composite calibration was interchangeable with the digital method. Conclusions: Within the limitations of this retrospective cohort, inter-implant distances below 3 mm, with the majority below 2 mm, were not associated with interproximal bone loss after up to 10 years of function. The digital workflow enabled distortion-free assessment of implant spacing and provided a reference for evaluating radiographic calibration methods. The present findings warrant confirmation in prospective studies with larger cohorts.