Definitive Abutment Research Articles

Effect of one-time placement of the definitive abutment versus multiple healing abutment disconnections and reconnections during the prosthetic phase on radiographic and clinical outcomes: A 12-month randomized clinical trial.

The aim of this investigation was to evaluate the effect on clinical and radiological outcomes of the one-abutment, one-time protocol (test) versus placing the definitive abutment on the day of functional loading after having disconnected and connected three times the healing abutment during the prosthetic phase (control). Forty patients with 80 implants were randomly allocated to either the test or the control group. Changes in the radiographic marginal bone levels (MBLs), clinical outcomes, prosthetic-related outcomes, and patient-reported outcomes measures (PROMs) were assessed and compared 6 and 12 months after functional loading. Thirty-seven patients with 74 implants were followed at 12 months. A statistically significant bone remodeling was observed in both groups following implant placement. MBLs were significantly greater in the control group at the 6- (-0.13 mm vs. -0.61 mm) and 12-month visits (-0.01 mm vs. -0.53 mm). Bone loss was significantly greater in the control group from surgery to 6 and 12 months and from loading to 6 and 12 months. The abutment height was significantly greater in the test group, however, there were no significant differences in the restorative angle. Similarly, there were no statistically significant differences between groups for the measured clinical variables (probing depth, plaque, and bleeding index) and PROMs. Disconnecting and reconnecting the healing abutment was associated with significantly higher bone loss after 12 months, as compared to the placement of the definitive abutment at implant installation.

The effect of one-time abutment placement on clinical and radiographic outcomes: A 5-year randomized clinical trial.

The aim of this study was to evaluate the long-term (5 years) clinical efficacy of the one-abutment one-time protocol (test) versus the standard of care by placing the definitive abutment on the day of the prosthetic delivery (control). In this study, 39 subjects with 60 implants were randomly allocated to either the test or the control group. Changes in the radiographic interproximal bone levels (DIB), modified sulcus bleeding index, probing depth, modified plaque index, papilla fill (Jemt score), incidence of peri-implantitis and peri-implant mucositis as well as patient-reported outcomes measures (PROMs) were collected and compared at 1, 3 and 5 years. At 5 years, the control group showed a greater, although not statistically significant, change in mean DIB values (0.97 mm vs. 0.53 mm). Regarding the other clinical parameters evaluated, no statistically significant differences were observed between groups at any time point. At 5 years, 51% of the implants presented peri-implant mucositis (25.5% in the control and 23.5% in the test), and only one implant in the test group developed peri-implantitis. The connection and disconnection of healing abutments during the healing period was not associated with higher long-term bone loss. Clinical outcomes and PROMs were similar between groups.

Posterior single implants immediately loaded using one abutment at one time and temporary abutment in the posterior mandible without bone augmentation: A report on six-month outcomes data obtained from a prospective randomized controlled split-mouth clinical trial

Background/Aim. Given that frequent manipulation of the abutment during immediate loading can have a negative impact on the surrounding peri-implant hard and soft tissues, the concept ?one abutment at one time? (OAO) has been introduced and documented in daily clinical practice. The aim of the study was to evaluate changes in peri-implant bone levels, clinical and radiographic parameters, and patient perspectives during the six-month follow-up period. Methods. The study was designed as a randomized controlled clinical trial. Patients with bilaterally healed sites in the posterior mandible received implants with a diameter of no less than 3.5 mm and a length of at least 8 mm. Based on randomization, patients were divided into a test group and a control group. Patients who were in the test group received implants that were immediately loaded with definitive abutments. In contrast, patients in the control group received implants where healing abutments were placed, followed by temporary abutments. Implants were immediately loaded with provisional restorations within the first seven days. They were delivered over the test group?s definitive abutment and the control group?s temporary abutment. Probing depth, bleeding on probing, clinical attachment level, plaque index, and keratinized tissue width were measured. Patient-Reported Outcome Measures and the Oral Health Impact Profile - 19 (OHIP-19) questionnaires were noted. Results. Out of 24 included patients, 22 completed the six-month follow-up. Peri-implant bone loss between study groups was comparable (mesial: t = -0.798, df = 21, p = 0.434; distal: t = 1.688, df = 21, p = 0.106), without statistical inter-group significance. OHIP-19 total scores significantly decreased after three months and remained similar six months after the implant placement in both groups without statistically relevant clinical inter-group changes. Conclusion. The OAO approach and provisional abutments showed comparable effectiveness regarding the immediate loading of posterior single implants.

Untreated Mineralized Dentin Grafts (UMDGs) vs Xenografts Around Immediately Placed Dental Implants in the Mandibular Anterior Region: A Randomized Controlled Clinical Trial.

The structural and compositional similarities between dentin and alveolar bone formed the basis for utilizing dentin for bone regeneration. Various authors recommended using treated mineralized, partially demineralized, and demineralized dentin grafts over xenografts because of their comparable clinical and radiographic results and lower costs. Therefore, the current study aimed at comparing the effect of untreated mineralized dentin grafts (UMDG) versus xenografts in vertical and horizontal augmentation around dental implants that were immediately placed in the mandibular anterior region. A total of 56 patients who required immediate dental implant placement in the lower anterior region were randomly allocated to group I (study), where ground dentin was washed with normal saline and placed around the dental implants, and to group II (control), where xenograft was used. The primary implant stability was measured at the time of implant placement. Secondary stability, plaque index (PI), bleeding index (BI), probing depth (PD), and keratinized mucosa width (KMW) were assessed at baseline (time of definitive abutment and temporary crown placement) and then at 3, 6, and 12 months. Pain and the number of analgesics consumed were assessed daily during the first postoperative week. Marginal bone loss (MBL) and radiodensity were assessed radiographically. There were no significant differences between both groups in terms of postoperative pain, the number of analgesic tablets consumed, peri-implant mucositis, or peri-implantitis. Both groups showed comparable results for the PI, BI, and BD. Moreover, there was no statistical difference between both groups with regard to primary implant stability and secondary stability at baseline and 12 months. Group I showed significantly lower secondary stability after loading at 3 and 6 months and significantly greater bone loss and lower bone density before exposure. KMW and MBL after exposure were significantly higher in group I at all time points. Although UMDG showed similar clinical results as xenografts, including primary and secondary implant stability, they had higher resorption rates than xenografts. Therefore, treatment of the dentin graft is required. Thus, the authors do not recommend using untreated mineralized dentin grafts.

Immediate Loading of Bicortically Engaged Long Implants in Maxillary and Mandibular Esthetic Region – A Clinicoradiographic Evaluation

Abstract Background: Bicortical engagement is the engagement of nasal cortical plate and basal cortical plate in maxillary and mandibular esthetic zone, respectively. These are longer implants which offer osseointegration along with high osseofixation. Increased length of implant provides increased bone–implant contact offering primary stability which permits immediate loading. Aim: The aim of the study was to clinicoradiographically evaluate immediate loading in bicortically engaged long implants in maxillary and mandibular esthetic region. Materials and Methods: Thirty patients with missing teeth in esthetic region were selected for the study. Implants were placed in both arches engaging nasal cortex and basal bone wherever required. One-time definitive abutment was placed and immediate loading was done. Results: No failure was observed in the study period of 9 months. The mean insertion and reverse torque was 66.67 ± 6.794 and 41.67 ± 3.101, respectively, indicating high primary stability. No pain, discomfort, infection, or implant mobility was observed. The mean crestal bone loss changes were statistically insignificant. Conclusion: Hundred percent implant survival was observed.

Assessment of the Peri-Implant Conditions for the Primary and the Repeated Abutment Placements: An Original Research.

Recurrent abutment substitutions may physically irritate the mucosal (soft tissue) barrier, which may cause additional toxic irritants and germs to enter the mucosal implant barrier and weaken the tissues surrounding implant. The creation of a "definitive abutment" may lessen the likelihood of tissue losses around the implant. Determining the characters of the peri-implant tissue after the placement of the definitive abutments and multiple abutment replacement was the goal of this study. Forty missing teeth were replaced with implants in matched subjects. Parameters assessed were "distance of cement enamel junction to alveolar crest and distance of CEJ to gingival margin; bleeding on probing, Sulcus probing depth, and peri-implant marginal bone loss." Subjects were randomly assigned for the two groups of intervention. All the measurements were documented at designated timelines and compared for the statistical variance where P < 0.05 was considered as significant. In the control and test groups, the peri-implant marginal bone level rose from baseline to 3 months. There were no appreciable differences between the CEJ-AC and CEJ-GM groups when the clinical and radiographic parameters of each group were evaluated. Throughout all of the time points, the soft tissue borders in both groups remained comparably steady. The study's findings suggest that using implants with definite abutments is more advantageous for obtaining better maintenance in terms of the health of the tissues that surround the implants.

Hard and Soft Tissue Alterations After Immediate Implant Placement and Provisionalization with Customized Definite Abutment in Esthetic Zone: A Retrospective Study.

To evaluate the hard and soft tissue alterations of immediate implant placement and provisionalization with customized definitive abutments in the esthetic zone. Single unsalvageable maxillary anterior teeth were replaced with immediate implant placement and provisionalization with definitive abutments in 22 participants. Digital impressions and CBCT images were obtained presurgery, immediately after surgery, and 6 months after surgery. Horizontal and vertical buccal bone changes in thickness and height (HBBT, VBBH), vertical changes for the gingiva margin, mesial and distal papilla height, and horizontal changes for soft tissue (HCST) were analyzed using a 3D superimposition method. Twenty-two participants completed the study. No implant failed, and there were no mechanical or biologic complications for any patients. At 6 months after surgery, the mean HBBT changes at 0, 1, 2, 3, 5, 7, 10, 11.5, and 13 mm were -0.92 ± 0.73, -0.83 ± 0.53, -0.82 ± 0.49, -0.70 ± 0.64, -0.65 ± 0.47, -0.50 ± 0.51, -0.15 ± 0.45, -0.10 ± 0.57, and -0.00 ± 0.64 mm, respectively. The mean VBBH change was -0.61 ± 0.76 mm. The mean HCSTs at -3, -2, -1, 0, 1, 2, and 3 mm sub- and supra-implant shoulder were -0.65 ± 0.54, -0.70 ± 0.56, -0.65 ± 0.51, -0.61 ± 0.56, -0.47 ± 0.54, -0.47 ± 0.59, and -0.46 ± 0.59 mm, respectively. The mean gingiva margin recession was -0.38 ± 0.67 mm. The mean mesial papilla height recession was -0.03 ± 0.50 mm. The mean distal papilla height recession was -0.12 ± 0.56 mm. The definitive abutment used with immediate implant placement and provisionalization could potentially maintain the buccal bone thickness and height. For the facial soft tissue, it also benefited the maintenance of the midfacial gingival margin position and papilla height during the 6-month follow-up. Int J Oral Maxillofac Implants 2023;38:479-488. doi: 10.11607/jomi.9914.

Single-Tooth Replacement in the Maxillary Esthetic Zone with Immediate Implant Insertion and Definitive Abutment Placement and Provisionalization: 1-Year Results of a Prospective Case Series.

This prospective longitudinal study evaluated the peri-implant soft tissue remodeling, marginal bone levels, and implant success rate of immediately placed single implants-which received a definitive zirconia abutment and provisional restoration at implant placement-in the maxillary esthetic zone. The final crown was delivered 7 days later. Patients (n = 26) presenting a single extraction-indicated lateral or central incisor with adequate bone volume were eligible for this study. Mesial and distal papilla levels (MPL and DPL, respectively), facial gingival level (FGL), and mesial and distal marginal bone levels (MMBL and DMBL, respectively) were assessed after 7 days and at 1, 2, 3, 6, and 12 months. Patients were classified according to gingival phenotype: thin (≤ 2 mm) or thick (> 2 mm). After 1 year, the implant success rate was 100%. Mean soft tissue recession was -0.04 ± 0.15 mm (MPL), -0.09 ± 0.02 mm (DPL), and -0.13 ± 0.18 mm (FGL). Mean bone remodeling at 1 year was 0.12 ± 0.17 mm (MMBL) and 0.13 ± 0.18 mm (DMBL). The marginal interproximal bone was above the implant platform in 100% of sites. Patients with thick phenotype showed significantly less papillary recession than thin-phenotype patients. Minimal peri-implant hard and soft tissue changes were observed at the 1-year follow-up.

SafetyCrown: a patient-centered, fully digital concept for immediate implant restoration following the one-abutment/one-time concept—a pilot case series of a new treatment concept

IntroductionThe patient-centered SafetyCrown-workflow enables the immediate restoration of posterior missing teeth and short free-end situations following one-abutment/one-time within three visits and only one surgical approach. This prosthodontic rehabilitation aims to combine the advantages of cemented and screw-retained restorations.ReportThe concept has been performed with 4 restorations in 3 patients and followed up for up to 1 year (mean: 11.2 months) without technical and/or biological complication. Visit 1: Intraoral optical impression, CBCT, and tooth shade selection. Virtual implant planning is performed, and a surgical guide is printed. After exporting the planned implant position, a tooth-colored abutment is fabricated from zirconia with a 1-mm supragingival cementation line, adhesively bonded to a titanium base. Visit 2: Fully navigated implant placement with insertion of the definitive abutment. Subsequently, optical impressions are prepared for A: immediate restoration using a PMMA crown without functional contacts; B: definitive crown fabricated from monolithic zirconia and individualized. The localization of the screw channel is marked using stain thus permitting precise screw channel access, if necessary. Visit 3: After osseointegration of the implant, the definitive crown is adhesively cemented supragingival. In a retrospective analysis of PROMs (‘How stressful was the treatment process […]?’ (0 = not stressful at all, 100 = very stressful), mean VAS score for SafetyCrown of 14 (SD 11.7) and 29.8 (SD 23.1) for standard procedure were present.ConclusionThe SafetyCrown offers a shortened, patient-oriented concept for implant-supported single-tooth reconstructions omitting second-stage surgery. Clinical performance and hypothesized prosthodontic benefits require confirmation via an RCT.

Assessment of Surgical and Radiographic Parameters for Abutment Height Selection: A Prospective Study with 1-Year Follow-up.

The "one-abutment, one-time" concept entails the placement of a definitive abutment at the time of implant placement, without removal during prosthesis manufacture, with the aim to promote a safer environment for the peri-implant tissues. Identifying surgical and radiographic parameters that can assist with the abutment height selection would facilitate the adoption of the one-abutment, one-time concept. Therefore, the aim of this study was to assess the role of surgical and radiographic parameters as predictive factors for abutment height selection in implant-retained single crowns. This prospective study assessed the role of surgical and radiographic measurements in the implant survival and success rates and marginal bone loss in implant-retained single crowns. Implants were placed in both healed sites and extraction sockets, and the distances between the implant platform and alveolar bone crest, implant platform and gingival margin, and buccal gap (when present) were recorded using a straight periodontal probe. Digital radiographs were made at implant placement (T0), abutment height selection (Ta), and 1-year follow-up (Tf), and the distance between the implant platform and the alveolar bone crest (mm) was assessed. Linear regression models and Pearson correlation were used to assess the influence of primary and secondary outcomes on abutment height. A total of 130 implants were placed in 68 patients. The mean surgical distance between the bone crest and the implant platform was 1.71 ± 1.01 mm, and the mean distance from the gingival margin to the implant platform was 3.94 ± 1.90 mm, while at the abutment selection appointment, the mean transmucosal height was 3.58 ± 1.50 mm. A high linear correlation was found between the selected abutment height and two primary outcomes: the radiographic implant platform to alveolar bone crest distance at T0 (r2 = 0.66; P < .001) and the transmucosal height at Ta (r2 = 0.81; P < .001). Radiographic measurements of the distance between the implant platform and the alveolar bone crest at implant placement can serve as an important parameter to select the abutment height for definitive restorations.

Full digital implant workflow utilizing the one-abutment one-time concept

This case presentation aims to demonstrate a full digital implant planning, surgical and prosthetic workflow utilizing the one-abutment one-time (OAOT) concept. Type III implant placement after socket preservation with platelet-rich fibrin (PRF) was scheduled for a patient at location 46. Initial intraoral scans with a corresponding digital wax-up and CBCT data were imported into implant planning software (SMOP). The surgical template was 3D printed, while a digital scan-body representing implant position was extracted and uploaded into CAD software (EXOCAD) in order to plan and mill a definitive custom hybrid zirconia abutment and a PMMA temporary crown prior to surgery. Static navigation for implant placement utilizing a pouch roll flap technique together with the placement of the definitive abutment and the temporary crown were used in order to achieve an immediate non-functional loading supplemented with the OAOT protocol. Four months postoperatively, a prefabricated zirconia framework (designed in the CAD software on top of the custom abutment) was porcelain veneered after rescanning the abutment intra-orally for 3D printed models and was delivered. The implant healed uneventfully resulting in a favorable soft tissue marginal contour without any buccal recession. Periapical X-rays showed no signs of marginal bone loss at the 1 and 2 years postoperative controls. The OAOT concept together with the utilized flap technique for soft tissue thickening resulted in zero bone loss and marginal gum stability. Digital technologies can help to preplan and fabricate individualized abutments prior to surgery to fulfill OAOT protocols.

Peri-implant Tissue Health in Bone-Level Implants with Repeated Abutment Replacements Versus Tissue- Level Implants with a Definitive Abutment: A Randomized Controlled Trial.

The present randomized controlled study was undertaken to evaluate and compare peri-implant hard and soft tissue changes between implants restored with multiple disconnections and reconnections of the abutment (control group) vs implants restored with a definitive abutment (test group). Twenty edentulous sites from 13 systemically healthy participants were selected for the study. The recorded clinical parameters were bleeding on probing (BOP) and peri-implant pocket depth (PIPD). The measured radiographic parameter was peri-implant marginal bone loss (PMBL). Two parameters were measured both clinically and by CBCT: distance from the cementoenamel junction to the alveolar crest and alveolar ridge width. At the time of surgery, sites were randomly assigned to either the control or test group. At 6 months, (1) BOP was absent in both groups, (2) PIPD increased in both groups and was significantly greater in the control group, and (3) the mean PMBL was significantly higher in the control group than the test group. Thus, it can be concluded that the use of implants with a definitive abutment could be more beneficial in achieving better maintenance of marginal peri-implant tissue health.

Comparative evaluation of peri-implant tissues in definitive and repeated abutment replacements: A randomized clinical trial.

Background:Repeated abutment replacements may insults the soft tissue (mucosal) barrier mechanically, that might initiate other toxic irritants and bacteria into the mucosal-implant barrier that may affect the strength of the tissues around implants. The development of the “definitive abutment,” might minimize the chances of peri-implant soft and hard tissue loss. Therefore, the study was designed to assess peri-implant tissue dimensions in dental implants with definitive abutment (Test group) and repeated abutment replacements (Control group).Materials and Methods:Twenty edentulous sites from systemically healthy participants were selected for the study. Parameters registered were bleeding on probing, Sulcus probing depth, peri-implant marginal bone loss (PMBL) and additionally, two parameters were measured both clinically and radiographically, which included distance of cement enamel junction to alveolar crest (CEJ-AC) and distance of CEJ to gingival margin (CEJ-GM). At the time of surgery, sites were allocated randomly to either test group or control group. All the measurements were recorded at baseline, 3 and 6 months.Results:The PMBL increased from baseline to 3 months in control (1.05 ± 0.28 mm) and test groups (0.65 ± 0.41 mm). When the clinical values of CEJ-AC and CEJ-GM were compared with their respective radiographic values, no substantial differences were noticed between both the groups. The soft-tissue margins in both the groups remained comparatively stable across all the time points.Conclusion:The findings of this study point toward the use of implants with definitive abutment are more beneficial in achieving better maintenance in terms of marginal peri-implant tissue health.

Immediate restoration of fixed full-arch prostheses placed on implants in both fresh and healed sockets using the flat one-bridge technique: a 7-year retrospective study

BackgroundThe aim of this retrospective study was to document the long-term clinical efficacy of a surgical-prosthetic technique (the flat one-bridge technique) involving the immediate restoration of both postextraction and nonpostextraction implants supporting full-arch restorations.MethodsImplants were placed by adapting the axis to the available bone. Flat definitive abutments were connected during surgery and never disconnected to compensate for eventual implant disparallelism. Bone grafting was performed when needed. The patients received a screw-retained provisional restoration within 48 h of surgery and a final screw-retained prosthesis within 1 year.ResultsSixty-six patients received 494 implants distributed in 75 prostheses. The median follow-up was 86 months (range 82–168 months). Only three implants had failed at the last follow-up. Implant survival was 99.6%.ConclusionThe flat one-bridge prosthetic protocol is a viable procedure with excellent long-term outcomes. No difference in clinical success could be observed between postextractive and nonpostextractive implants.

Bone‐level changes around implants with 1‐ or 3‐mm‐high abutments and their relation to crestal mucosal thickness: A 1‐year randomized clinical trial

To evaluate 1-year bone-level changes around subcrestal platform-switching implants with 1 or 3 mm definitive abutments. The influence of mucosal thickness on bone-level alterations was further analysed. Implants were placed in the posterior sextants and positioned 1.5 mm subcrestally with an abutment of 1 or 3 mm height. Final restorations were delivered after 16 weeks. Radiographic measurements of inter-proximal bone level were the primary outcome and were adjusted by vertical mucosal thickness. Peri-implant clinical conditions and resonance frequency analysis were also compared. A total of 65 subjects with 99 implants were analysed. The overall 1-year implant survival rate between the 1- and 3-mm groups was 96.4% and 94.4%, respectively. Statistically significant lower inter-proximal marginal bone-level changes were observed in the 3-mm group (1 mm: -0.17 ± 0.02 mm at mesial and -0.21 ± 0.02 mm distal; 3 mm: -0.03 ± 0.02 mm at mesial and -0.03 ± 0.02 mm and distal; mesial: p=.001; distal: p < .001). Initial vertical mucosal thickness was not correlated with inter-proximal marginal bone loss. Subcrestal implants with 3-mm abutment were associated with minimal inter-proximal bone loss. Independent of the abutment height, crestal mucosal thickness was not correlated with bone loss.

One-Abutment One-Time Effect on Peri-Implant Marginal Bone: A Prospective, Controlled, Randomized, Double-Blind Study.

Objective: To evaluate the peri-implant hard tissue change at 6 and 12 months after implant placement between definitive abutment placed at the same time of implant surgery, never removing it, and healing abutment disconnected and reconnected three times until the placement of the final rehabilitation. Material and methods: Each partial edentulous patient could receive between 1 and 4 platform-switched implants in the posterior regions. If the implants had primary stability—implant stability quotient (ISQ) equal to or greater than 50, they were randomized to the test group with the abutment inserted at the same time of implant placement (DA) or to the control group, receiving a healing abutment (PA). At 6 and 12 months after surgery, data related with vertical bone level changes (primary outcome) and other clinical parameters (implant mobility, bleeding on probing, probing depth, plaque index) were assessed. Results: 53 implants were included in the trial and completed 12 months follow-up (overall survival rate: 100%). All implants achieved primary stability, with an average ISQ value of 80.9 on the day of surgery. From surgery to 6 months, the mean bone loss was 0.14 ± 0.18 mm for the DA group and 0.23 ± 0.29 mm for the PA group, without statistical significance difference. Between 6 and 12 months, the mean bone loss was 0.14 ± 0.21 mm for the DA group and 0.21 ± 0.27 mm for the PA group, also without statistical significance between the two groups. There were no statistically significant differences (p = 0.330) in total bone loss after 12 months between the control and the study groups. Conclusions: The one abutment one time protocol has at least an equivalent effect on the peri-implant bone level changes when compared with the use of healing abutments that are disconnected and reconnected at least three times.

Resistance to dynamic and static loading of the implant mounts on its respective implant

Introduction: Implant restorations should endure a variable range of forces over a long period of time. Some commercial brands offer the implant together with an accessory called “implant mount” or “implant holder,” which might be used as a temporary abutment. However, scientific literature in the use of implant holders as abutments for restorations is scarce. Objectives: The purpose of this in vitro study was to compare the load at which implant holders of Implant Direct® and Zimmer® fail under static compression after being subjected to fatigue, and to compare the gap produced between the implant–holder complexes after dynamic loading. Materials and Methods: The test protocol was based on the recommendation of ISO 14801. Five implant–implant holder assemblies of each brand were subjected to dynamic loading. A load of 250 N was applied at 5 × 106 cycles and at 15 Hz stress frequency (Eden Prairie, MN, USA). The gap (μm) at the interface was measured postfatigue using scanning electron microscopy (S-3700N, HITACHI, Japan), and afterward, static loading was applied and the maximum load (N) after the point of failure was established. Implant–definitive abutment complexes were used as controls. Data were analyzed by means of a central tendency measurement test Mann–Whitney U-test (nonparametric). Results: There was no difference between both the implant holder groups (P ≤ 0.05); however, a slight trend of greater resistance was observed for the Zimmer® group. The gap in the interface was greater for Implant Direct® implants, but the difference was not statistically significant. Conclusion: No significant differences were found in terms of the maximum load under compression or the interface gap after the dynamic loading in the two experimental groups.

Laser microgrooved vs. machined healing abutment disconnection/reconnection: a comparative clinical, radiographical and biochemical study with split-mouth design

BackgroundRepeated removal and replacement of healing abutments result in frequent injuries to the soft tissues.PurposeThe purpose of this study was to evaluate the effect of disconnection/reconnection of laser microgrooved vs. machined healing and prosthetic abutments on clinical periodontal parameters, marginal bone levels, and proinflammatory cytokine levels around dental implants.Material and methodsTwenty-four patients each received 2 implants with one-stage protocol in a split-mouth design on the same jaw. In each patient, one healing and prosthetic abutments with a laser microgrooved surface (LMS group) and one healing and prosthetic abutments with machined surface (MS group) were used. Four months following implant placement (T0), the healing abutments were disconnnected and reconnected three times to carry out the impression procedures and metal framework try-in. Four weeks later (T1), definitive prosthetic abutments were installated with screw-retained crowns. Modified plaque index (mPI), modified gingival index (mGI) bleeding on probing (BOP), and probing depth (PD) were recorded at T0 and T1. At the same time points, samples for immunological analyses were taken from the sulcus around each implant. Peri-implant crevicular fluid (PICF) samples were analyzed for interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor (TNF)-α levels using the ELISA kit.ResultsAt T0 and T1, mPI and mGI showed no statistical difference between the two groups, while higher PD and BoP values were noted for the MS group (P < 0.05). The mean PICF volume and mean concentrations of IL-1β, IL-6, and (TNF)-α in the LMS group were statistically less than those in the MS group (P < 0.05). In addition, comparison of IL-6 and IL-1β mean concentrations at T0 and T1 in the MS group showed a statistically significant increase (p < 0.05) over time, which was not noted for the LMS.ConclusionDisconnection/reconnection of healing and prosthetic abutments with a laser-microgrooved surface resulted in less inflammatory molecular response compared with conventional machined ones.Trial registrationClinicalTrials.govNCT04415801, registered 03/06/2020

BellaTek Encode Definitive Abutments

BellaTek Encode Definitive Abutments

One Abutment One Time: A Multicenter, Prospective, Controlled, Randomized Study.

Aim: (PRIMARY) Assess the changes in bone level (6 and 12 months after implant placement) between the test (definitive abutment (DEF)) and control (healing abutment (HEA)) groups. (SECONDARY) Assess the changes in bone level (6 and 12 months after implant placement) between the 1 mm high abutment group and 2 mm abutment group. Evaluate changes in implant stability recorded with analysis of the resonance frequency (RFA) Osstell system, at 6 and 12 months after implant placement, between the control group (HEA) and test (DEF). For the DEF group, the abutment was placed at the time of the surgery and was never removed. For the HEA group, the abutment was removed three times during the manufacture of the crowns. The abutments used were 1 mm high (Subgroup A) and 2 mm high (Subgroup B). Materials and methods: A total of 147 patients were selected between 54.82 ± 11.92 years old. After implant placement, patients were randomly distributed in the DEF and HEA group. After the implant placement, a periapical radiograph was taken to assess the peri-implant bone level; the same procedure was carried out 6 and 12 months post-placement. To compare the qualitative variables between the groups (HEA/DEF), the Chi-square test was used; for quantitative (MANOVA). Results: After a year, the accumulated bone loss was 0.48 ± 0.71 mm for the HEA group and 0.36 ± 0.79 mm for the DEF group, without statistical significance. Differences were only found due to timing (time) between 0 and 6 months (=0.001) and 0 and 12 months (0.001), with no differences attributable to the study groups (DEF and HEA). The accumulated bone loss (1 year) was 0.45 ± 0.78 mm for the 1 mm abutment group and 0.41 ± 0.70 mm for the 2 mm abutment group (p = 0.02). No differences were observed in implant stability between groups. Conclusions: The “One Abutment—One Time” concept does not reduce peri-implant bone loss compared to the connection–disconnection technique. The height of the abutment does influence bone loss: the higher the abutment, the lower the bone loss.