Marginal Bone Level Changes Research Articles

Dental implant site preparation with conventional rotary drill or piezosurgery: five-year after placement results from a within person randomised controlled trial

PurposeTo evaluate whether there are clinical benefits by preparing dental implant sites using piezosurgery instead of conventional rotary drills in healed bone crests and if initial crestal soft tissue thickness could have an impact on marginal bone loss.MethodsTwenty-five partially edentulous patients requiring two single implants in molar/premolar areas had each site randomly allocated to either piezosurgery or to conventional rotary drill preparation according to a split-mouth design. Definitive screw-retained metal-ceramic crowns were delivered after 6 months. All patients were followed to 5 years after placement. Outcome measures were: implant/crown failures, complications, peri-implant marginal bone level changes, resonance frequency analysis (RFA), and time required to complete site preparation, recorded, when possible, by blinded assessors.ResultsNo patients dropped-out and no implant failed. Five years after placement, there were no statistically significant differences for complications (only one complication in the piezo group: difference = 0.04; P = 1), for peri-implant bone loss (difference = −0.11 mm; 95% CI −0.24 to 0.01; P = 0.083), and for RFA changes (6 months) (difference = −0.35; 95% CI −1.95 to 1.25; P = 0.672 between groups). Significantly more time was needed to prepare implant sites with piezosurgery (difference = 236.8 s; 95% CI −286.12 to −187.48; P < 0.0001). Initial soft tissue thickness had no effect on peri-implant bone loss (estimate = 0.05; 95% CI −0.03; 0.12; P = 0.239).ConclusionsNo clinically appreciable differences were noticed when placing implants using piezosurgery or conventional instrumentation with rotary drill, however, the preparation with rotary drills was on average 4 min faster. No effect of initial crestal soft tissue thickness was observed on peri-implant bone loss.

Long-Term Clinical and Radiographic Outcomes of Hydrophilic Implants: A 10-Year Study in a Specialist Private Practice.

To report the 10-year clinical and radiographic outcomes of implants placed in grafted (GBR) and non-grafted (no-GBR) sites in a Swiss specialist private practice using hydrophilic implants with a low surface roughness flange. Fifty consecutively enrolled patients received 159 hydrophilic implants with a low surface roughness flange. A first re-evaluation was performed 1 year after delivery of restoration (T1). An additional examination was performed at the 10-year follow-up (T2) including the assessment of clinical (i.e., periodontal/peri-implant pockets probing depths (PPD) (mm), full-mouth bleeding score (%), implant survival rate, mid-buccal keratinized mucosa (KM) width in mm, and peri-implant phenotype), and radiographic (i.e., marginal bone level change [ΔMBL]) outcomes. Biological, mechanical and technical complications were also recorded. Out of the initial cohort, 22 patients (9/40.9% male and 13/59% female) and 63 implants (47 with GBR, 16 without GBR), could be re-examined at T2. Overall, ΔMBL (T2-T1) was -0.56 ± 0.96 mm. In the GBR group, ΔMBL were significantly higher at the distal sites compared to the no-GBR group (-0.75 ± 1.17 mm vs. -0.12 ± 1.29 mm, p = 0.045), however, in the GBR group MBL started at a higher level at T1 but were similar with the no-GBR group at T2. Implant survival was 100% with only very few technical complications (6.3%). Mean PPD amounted to 3.84 ± 1.00 mm with significantly higher values in the GBR group (3.98 ± 1.08 mm vs. 3.45 ± 0.60 mm; p = 0.016). Nineteen implants (30.1%) were diagnosed with peri-implant health while 44 (69.9%) presented with peri-implant mucositis. Within the limitations of this study, favorable clinical and radiographic conditions were recorded around hydrophilic implants with a low surface roughness flange placed in pristine and augmented bone after 10 years in function.

Metal-Free Custom-Made Zirconia Implants-A Prospective 5-Year Follow-Up Single-Arm Clinical Trial.

Dental implants made of zirconia (ZrO2) are a potential alternative for titanium implants in dentistry because of their good biocompatibility, mechanical properties and excellent aesthetic results. However, solid long-term scientific data to prove clinical success of ZrO2 implants are scarce. The aim of this study was to describe and to examine the clinical performance of custom-made two-piece ZrO2 implants, to identify possible influencing factors: a) manipulation of the implant after placement and b) the occlusal scheme on the survival rate, and to evaluate the performance of the implant-supported crown. This follow-up study collected and examined the 5-year data to answer the main question: What are the survival and the success rates of custom-made ZrO2 implants in the maxillary premolar region after 5 years? Of the 31 included patients in this prospective 5-year follow-up single-arm clinical trial, 30 received a custom-made ZrO2 implant to replace a missing single maxillary premolar, which was subsequently restored with a lithium disilicate crown. Parameters regarding clinical performance, marginal bone-level (MBL) changes, and patient-related outcome measures (PROMs) were assessed preoperatively, at the baseline, as well as 1 and 5 years after crown placement. Chances of survival and success of the implant were calculated and displayed using Kaplan-Meier statistics. Kaplan-Meier survival analysis was also performed with stratification based on the variables "manipulation of the implant prior to impression taking" and "occlusal scheme" and compared using log-rank tests. Bone-level moderation in time was compared using a paired samples t-test. Patient's expectations and satisfaction after 5 years were compared as a measure of fulfilled expectations, using a Wilcoxon signed-rank test. Performance of the implant-supported crowns was evaluated using validated criteria. Survival and success probabilities after 5 years were, respectively, 75.8% (95% CI [60.0%; 91.0%]) and 71.0% (95% CI [54.0%; 88.0%]) for the custom-made ZV3 implants. No significant differences in survival rate were found after stratification on "manipulation of the implant" and on "occlusal scheme." Mean bone-level alteration between baseline and the first follow-up was +0.06 mm (95% CI [-0.23 mm; 0.12 mm]; SD = 0.42 mm) and between baseline and the second follow-up was +0.04 mm (95% CI [-0.35 mm; 0.26 mm]; SD = 0.54 mm). Patients' satisfaction for patients with implants still in function after 5 years was 91.7% (IQR = [90.5%-97.3%]), indicating satisfaction with the treatment. Pooled satisfaction in patients with successful implants after 5 years was significantly higher than patients' expressed expectations before treatment. None of the crowns failed, and no interventions were required. Survival rate of these particular ZV3 implants in our study was lower than expected and clinically not acceptable. Hence, ZV3 implant placement as applied in this study cannot be recommended for clinical practice. Further research on the different appearances of mechanical failure in ZrO2 implants would be highly recommended before a larger prospective randomized clinical trial is conducted to evaluate treatment with custom-made ZrO2 dental implants.

Full-arch prostheses supported by implants with different macrostructures: A multicenter randomized controlled trial.

This study evaluates the clinical performance of implants with hydrophilic surface and two different macrostructures: cylindrical with perforating triangular threads (CT) and cylindrical-tapered with the association of square and condensing and perforating triangular threads (TST). This was a multicenter split-mouth, simple-blinded, randomized, and controlled trial. Thirty patients with edentulous mandible received two CT and two TST implants. Primary stability was determined by insertion torque and resonance frequency analysis (RFA). Implants were loaded with full fixed-arch prostheses within 24 h after insertion. Clinical parameters (visible plaque index, marginal bleeding index; bleeding on probing; probing depth; and clinical attachment level) and the RFA were assessed at 2, 6, 12, and 24 months after implant loading. Marginal bone level changes were measured by comparison of standardized radiographs taken on the day of implant placement and 6, 12, and 24 months thereafter. Twenty-eight patients completed the 2-year follow-up. The survival rates were 99.16% for CT implants and 100% for TST implants. One CT implant was lost until the 2 months follow-up. No significant differences were found between the two implant types for marginal bone level changes (CT 0.34 [0.24; 0.55 mm]; 0.33 [0.18; 0.55 mm]; 0.41 [0.12; 0.7 mm] vs TST 0.36 [0.14; 0.74 mm]; 0.33 [0.23; 0.63 mm]; 0.30 [0.20; 0.64 mm] at 6, 12, and 24 months, respectively) and other clinical parameters. The macrostructure of the implants had no influence on survival rate, primary and secondary stability, marginal bone level changes, and peri-implant clinical parameters outcomes. Both implants can be predictably used for immediate loading of full-arch mandibular prostheses.

Comparison of three approaches for treating the bony access window in lateral sinus floor elevation: a retrospective analysis

The aim of this study was to retrospectively determine the effects of applying different treatment methods to the bony access window on the healing outcomes in lateral sinus floor elevation (SFE). Lateral SFE with implant placement was performed in 131 sinuses of 105 patients. The following three treatment methods were applied to the bony access window: application of a collagen barrier (group CB), repositioning the bone fragment (group RW) and untreated (group UT). Radiographic healing in the window area, augmented bone height changes and marginal bone level changes were examined. Mixed logistic and mixed linear models were analyzed. Over 4.3 ± 1.4 years of follow-up, the implant survival rate was 100% in groups CB and UT, and 96.9% in group RW. The treatment applied to the window did not significantly influence the radiographic healing in the window area, augmented bone height changes or marginal bone level changes (p > 0.05). The healed window areas had generally flat morphologies and were fully corticalized. The mean changes in the augmented bone were less than 1.5 mm in all groups. Marginal bone level changes were minimal. In conclusion, Healing outcomes were not different among three different methods to treat the bony access window in lateral SFE.

Horizontal Guided Bone Regeneration of the Posterior Mandible to Allow Implant Placement: 1-Year Prospective Study Results.

Assess whether horizontal ridge augmentation with guided bone regeneration (GBR) using deproteinized bovine bone mineral (DBBM), autologous bone, and a resorbable collagen membrane supports successful implant placement. This open, prospective, single-cohort, multicenter clinical study included patients with ridge defects that required GBR prior to implant insertion. The primary endpoint was radiologically assessed bone gain after 8 months post-GBR, measured at the center of planned implant sites. Secondary endpoints included implant survival and success, marginal bone levels (MBLs), MBL changes, and soft tissue health. Of 45 patients evaluated 8 months post-GBR, nine experienced dehiscence in the first 3 weeks of the healing period. GBR led to radiologically determined mean bone width gain of 4.0 ± 1.5 mm and 4.8 ± 1.7 mm, measured 1 and 3 mm from the top of the crest, respectively, allowing successful implant placement in 44 patients (97.8%). The cumulative implant survival and success rates were 98.9% and 95.5%, respectively. MBLs were stable: -1.18 ± 0.64 mm at definitive prosthesis placement (DPP) and - 1.07 ± 0.74 mm at 1 year. Soft tissue health and esthetics (plaque and bleeding indices, papilla, keratinized mucosa, and pink esthetic score) improved from DPP to 1 year. Patients were highly satisfied with implant function and esthetics, and their oral health-related quality of life improved. GBR using DBBM and a collagen membrane offered a safe and effective treatment option for horizontal ridge augmentation sufficient to support implant-based tooth rehabilitation. Registered at ClinicalTrials.gov NCT03028922 (registrations sites, as above listed affiliations, first posted January 23, 2017).

Clinical Outcomes of Full Arch Immediate Fixed Prostheses Supported By a Novel Implant System with Low Speed Site Preparation A 5 Years Retrospective Case Series

Background: The aim of this case series was to evaluate the 5-years clinical and radiographic outcomes of immediate full-arch fixed prosthesis supported by a novel implant system characterized by a low-speed site preparation protocol. Methods: Six medically compromised patients (3 females and 3 males) were consecutively enrolled and treated. Each patient received a fixed full-arch rehabilitations supported by two axial and two tilted implants. A total of 24 implants (N1 System, Nobel Biocare AB, Göteborg, Sweden) were placed in three mandibles and three maxillae using a low-speed drilling protocol with no irrigation. Prosthetic loading was applied within 2 hours of surgery, while then definitive restorations were placed 4 months later. Patients were scheduled for follow-up every 6 months up to 2 years and then annually. Radiographic evaluation of marginal bone level change was performed on regular intervals. Results: Between February 2019 and July 2019, six patients received a full-arch fixed prosthesis on four implants. All implants reached a minimum insertion torque of 30 Newton for immediate loading. After 5 years of observation (range 62-67 months), no implants failed and all definitive prostheses were stable and functional, resulting in a cumulative survival rate of 100%. After 5 years, the marginal bone loss was 1.46 ± 0.16 mm for the mandible and 1.85 ± 0.18 mm for the maxilla. Two implants (one axial and 1 tilted) in 1 patient treated in the maxillary arch reported more then 2 mm of marginal bone loss after 5 years. Conclusions: Within the limitations of this study, the successful medium-term results seem to confirm that immediate fixed full-arch rehabilitation, supported by two anterior axial and two posterior tilted implants, could be an effective and biologically beneficial treatment for complete arch edentulism. The reduced bone remodeling evidenced after 5 years of function confirm the biologically friendly concept behind this novel implant system.

Similar short-term outcomes for bone-level implants with or without intermediate abutments.

A single-center (university-setting), prospective, longitudinal, split-mouth, single-blind, randomized controlled clinical trial investigated peri-implant parameters of bone-level implants restored with either screw-retained prostheses connected directly to the implants or with intermediate abutments over a 3-year period. The study adhered to the ethical principles of the Helsinki Declaration and the CONSORT guidelines. Ethical approval was granted, and the trial was registered at Clinicaltrials.gov . Participants included were over 18 years of age, had a plaque index below 25%, and were missing at least two adjacent teeth, allowing for rehabilitation with screw-retained fixed partial prostheses over two implants and 2-4 prosthetic units. Exclusion criteria included long-term use of medications affecting bone metabolism, smoking more than 10 cigarettes per day, history of local radiotherapy, untreated periodontitis, and the need for rehabilitation in the anterior sextant of the maxilla. The primary clinical outcome was marginal bone loss (MBL), while secondary outcomes included probing pocket depth (PPD), plaque index (PI), bleeding on probing (BOP), and patient-reported outcomes (PROs). The study schedule included a screening (visit 1), implant surgery (visit 2), stage-two 8 weeks post-surgery (visit 3), impressions taken 4 weeks post stage-two (visit 4), baseline standardized radiograph (visit 5), followed by 6-month (visit 6), 12-month (visit 7), and 36-month (visit 8) follow-up visits. Descriptive statistics and quantitative measures included means, standard deviations (SDs), minimum and maximum values, and 95% confidence intervals (CIs). Clinical parameters (six sites per implant) measured were MBL, PPD, PI, and BOP. Paired t tests were utilized for intragroup comparisons across different time points and intergroup comparisons at each time point. PROs at 36 months were compared using Student's t test. The alpha significance level was set at 0.05. The study included 36 patients (72 implants), with two not completing the follow-up due to death and relocation. No implants showed signs of inflammation or mobility. Mean interproximal bone level (IBL) at baseline was 0.13 mm ± 0.15 mm for the control group and 0.10 ± 0.13 mm for the test group. At the 36-month follow-up, mean IBL was 0.13 ± 0.18 mm for the control group and 0.20 ± 0.24 mm for the test group, with no significant differences (F(1, 32) = 1.06; p > 0.05). Clinical parameters (PPD, BOP, PI) at 36 months showed no significant differences between groups. Minor complications occurred in 6.7% of the control group and 5.3% of the test group. PROs indicated no significant differences in general satisfaction, esthetics, comfort, phonetics, and masticatory function between the groups. After a 36-month follow-up, bone-level implants restored with CAD/CAM prostheses directly connected to the implants displayed similar clinical outcomes, PROs, and marginal bone level changes as those restored with intermediate standardized abutments.

Guided versus freehand single implant placement: A 3-year parallel randomized clinical trial

ObjectivesThe present parallel randomized clinical trial aimed to assess, after a 3-year follow-up period, whether the choice of surgical technique—either manual or guided—and of the operator - non-expert operator or skilled - can affect the stability of peri‑implant marginal bone levels in implants placed 1 mm sub-crestal. Materials and methodsPatients received platform-switched implants (Anyridge, MegaGen Implant Co., Gyeongbuk, South Korea) featuring a 5-degree internal conical connection and supporting single screw-retained fixed crowns. The implants were randomly assigned to be placed through a digitally static guided surgery procedure (Test group - GS) or a freehand surgical technique (Control Group - FH). A non-expert operator (fewer than 20 implants placed in his professional activity) was selected to perform procedures for the GS Group, while a skilled operator (with over 1000 implants placed in his professional activity) was chosen for the FH Group. Marginal bone level (MBL) was measured at prosthesis installation (t0) and at 1 (t1), 2 (t2) and 3 years (t3) of follow-up. Changes in MBL from t0 to t3 were analyzed through periapical radiographs. Moreover, MBL changes at all time points were correlated to different supra-crestal soft tissue heights (STH): less than 3 and ≥ 3 mm, respectively. Results60 implants in 18 patients were examined, with 30 implants allocated to the GS group and 30 to the FH group. The difference in MBL change between the two groups was 0.11 ± 0.22 mm, which was not statistically significant (p = 0.61). At the time of prosthetic loading, the mean MBL for implants with STH less than 3 mm was 0.33 mm higher than implants with STH ≥ 3 mm, though this difference was not statistically significant (P = 0.065). ConclusionsDigitally static guided implant placement, performed by a non-expert operator, does not limit marginal bone remodeling, when compared to a freehand procedure performed by an experienced operator. Clinical significanceAfter correct and careful planning, early marginal bone levels (MBL) around conical connection, platform-switched implants placed sub-crestally may be stable in time. Digital planning and surgery have the potential to assist non-expert clinicians in achieving implant placements with comparable outcomes to those performed by experts.

Clinical and radiographic evaluation of implant-supported single-unit crowns with cantilever extensions: A systematic review and meta-analysis.

The purpose of this systematic review and meta-analysis was to analyze the clinical and radiographic outcomes of patients rehabilitated using a single implant supporting a crown with a cantilever extension or two implants supporting two single crowns. Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2020 guidelines, a systematic review of relevant literature published from 2000 was conducted in the Cochrane Library, Scopus, and MEDLINE databases. Moreover, a manual search was performed. A meta-analysis of the resulting data was carried out. Peri-implant marginal bone level, probing pocket depth, prevalence of technical and mechanical complications, implant survival rate, and prosthesis survival rate were assessed. The meta-analysis showed a non-statistically significant change in the peri-implant marginal bone level and probing pocket depth in the cantilever group and revealed a non-significant prevalence of technical complications, showing a 27% rate in the cantilever group. The analysis of the prosthesis survival rate in the cantilever group showed a mean survival rate of 99% while the comparison of the implant survival between the two groups revealed an odds ratio of 0.50. The use of a single implant supporting a crown with a cantilever extension does not result in lower implant survival rate if compared with two implants supporting two single crowns. Moreover, a high prosthesis survival rate was observed in the cantilever group even if the high prevalence of complications should be carefully considered by the clinician.

Alveolar ridge preservation and its impact on marginal bone level changes around dental implants: A retrospective, cohort comparative study.

This retrospective study compared the outcomes of implants placed in alveolar ridge preservation (ARP) treated sites with those in spontaneously healed (SH) sites. The study included patients presenting with one implant placed in an ARP-treated socket and one in an SH site. The primary outcome was the comparison of Marginal Bone Level Changes (MBLC). Statistical analysis was performed to identify factors influencing MBLC, including age, gender, smoking, parafunctional habits, and prosthetic emergence angle. Of these, 28 patients (23 females, 82.1%) were included in this analysis. Sockets in the SH group were classified as type I, whereas type II sockets were more common in the ARP group. The SH group exhibited significantly higher MBLC than the ARP group (p = 0.032), with values, respectively, of 1.00 [0.25; 1.62] and 0.40 [0.00; 1.00] mm. Among all evaluated parameters, the performance of ARP was the only factor significantly affecting MBLC (β = -0.72, SE: 0.32, p = 0.026). Age, gender, smoking, parafunctional habits, and prosthetic emergence angle did not significantly affect MBLC. The study shows the potential role of ARP in maintaining stable marginal bone levels around implants. In our sample, ARP significantly reduced MBLC compared with spontaneous healing, highlighting its possible impact in clinical practice for better peri-implant bone stability.

Marginal Bone Level Changes Evaluation of Long-term Functional Dental Implants with the Implant Disease Risk Assessment Diagram: A 2 to 6 Years Follow-up Retrospective Study.

Purpose: This study aimed to evaluate the relationship between risk profile assessments of dental implants that have been in function for at least two-year and peri-implant marginal bone loss during the follow-up period using the Implant Disease Risk Assessment Diagram. Material and Methods: A total of 70 patients and 170 implants who had been functionally loaded for at least two years and who attended follow-up sessions were included in the study. Full-mouth plaque index (PI), gingival index (GI), probing depth (PD), bleeding on probing, clinical attachment level (CAL), and peri-implant modified plaque index, modified bleeding index, PD, keratinized mucosal width (KMW), CAL and GR were recorded. According to the IDRA risk diagram, participants and dental implants were divided into low, moderate, and high-risk groups. Marginal bone level (MBL) was measured on periapical radiographs obtained at functional loading (T0) and at the last follow-up session (T1), and mesial and distal marginal bone level changes (ΔMBL) were calculated as T1-T0. Results: A statistically significant correlation was found between the periodontitis history and periodontitis susceptibility and IDRA classification at the patient-level. Full-mouth GI, PD, and BOP were found to be statistically higher in the high-risk IDRA group. No statistically significant result was found between the mesial and distal ΔMBL between the IDRA risk groups.Conclusions: In this study, IDRA risk level increased especially by periodontitis susceptibility and periodontitis history, but no significant difference was found between risk groups in terms of ΔMBL.

Immediate single-tooth implant placement in bony defect sites: A 10-year randomized controlled trial.

It is unclear whether an intact buccal bony plate is a prerequisite for immediate implant placement in postextraction sockets. The aim of this 10-year randomized controlled trial was to compare peri-implant soft and hard tissue parameters, esthetic ratings of, and patient-reported satisfaction with immediate implant placement in postextraction sockets with buccal bony defects ≥5mm in the esthetic zone versus delayed implant placement after alveolar ridge preservation. Patients presenting a failing tooth in the esthetic region and a buccal bony defect ≥5mm after an extraction were randomly assigned to immediate (Immediate Group, n=20) or delayed (Delayed Group, n=20) implant placement. The second-stage surgery and provisional restoration placement occurred 3months after implant placement in both groups, followed by definitive restorations 3months thereafter. During a 10-year follow-up period, marginal bone levels (primary outcome), buccal bone thickness, soft tissue parameters, esthetics, and patient-reported satisfaction were recorded. The mean marginal bone level change was -0.71±0.59mm and -0.36±0.39mm in the Immediate Group and the Delayed Group after 10years (p=0.063), respectively. The secondary outcomes were not significantly different between both groups. Marginal bone level changes, buccal bone thickness, clinical outcomes, esthetics, and patients' satisfaction following immediate implant placement, in combination with bone augmentation in postextraction sockets with buccal bony defects ≥5mm, were not statistically different to those following delayed implant placement after ridge preservation in the esthetic zone. Immediate implant placement in case of a failing tooth is a favorable treatment option for patients because it considerably shortens treatment time and the number of surgical treatments. The question is if an intact buccal bone wall is necessary for immediate implant placement. A 10-year study was performed in which 20 patients with a failing tooth in the frontal region of the upper jaw were treated with immediate implant placement and were compared with 20 patients in whom a more conventional treatment strategy was followed in which the failing tooth was first removed and the bone gap restored and the implant placed in a second step. After a 10-year follow-up period, it appeared that the bone around the implant was very stable, gums were healthy, and patients were very satisfied with the result. There was no difference between the two treatment procedures. Such results mean that professionals can discuss the procedure with the patient and apply the individual's preference.

Clinical efficacy of a two-piece abutment conforming to the concept of one abutment one time in the posterior region: A clinical pilot study.

To assess the impact of a two-piece abutment workflow on enhancing the stability of the alveolar bone and gingiva surrounding the dental implant, and to determine the level of patient satisfaction. A total of 48 patients with dentition defect in the posterior region were included and divided into two groups: the two-piece abutment workflow (TAW) and the sealing screw with submerged healing workflow (SHW). Marginal bone level (MBL), soft tissue indicators, oral hygiene indicators, and patient satisfaction were assessed and recorded partially at 0, 3, 6, and 12 months after surgery. The primary outcome was the change of MBL in different time periods. A generalized linear mixed model (GLMM) was used to take into account the correlated nature of the data, and adjust for potential confounding factors within inter-group differences. The survival rate of implants and prosthesis reached 100% at 12-month follow-up, with an average decrease of 0.25 mm (SD 0.23 mm) of MBL in the TAW group and 0.48 mm (SD 0.45 mm) in the SHW group. The change of MBL in the TAW group (0.15 ± 0.31 mm) was significantly lower than the SHW group (0.41 ± 0.41 mm) through the analysis of GLMM within 6 months, while no significance was found in 12 months. Moreover, less gingival pain and oppression during prosthesis loading, and less time consumption overall duration were showed in the TAW group through Visual Analogue Scale (VAS, p < 0.05). Within a 6-month period, the two-piece abutment workflow showed superior efficacy in preserving the integrity of the marginal bone level. Furthermore, it streamlined treatment procedures and mitigated discomfort, hence increasing patient satisfaction.

Esthetically driven immediate provisionalization in the anterior zone: 5-year results from a prospective study evaluating 3.0-mm-diameter tapered implants

ObjectivesEvaluate the 5-year safety and efficacy of a narrow-diameter (3.0 mm) implant that was immediately provisionalized with a single crown in the maxillary lateral incisor or mandibular central or lateral incisor area.Materials and methodsAn open, prospective, single-cohort, multicenter study was conducted, in which narrow-diameter implants were placed in fresh, healed extraction, or congenitally missing sites. All patients were required to meet strict criteria for immediate loading. The primary endpoints were marginal bone levels (MBL) and MBL changes (MBLC) from implant placement to 5-year follow-up. Secondary endpoints included cumulative 5-year survival and success rates, soft tissue health, and esthetic parameters.ResultsA total of 91 implants were placed in 77 patients. The mean MBL remained stable from the 1-year (− 0.79 ± 0.73 mm, n = 75) to 5-year (− 0.74 ± 0.87 mm, n = 65) follow-up. A marginal bone gain of 0.11 ± 0.83 mm was observed from the 1-year to 5-year follow-up. The cumulative 5-year survival rate was 96.5%, and the cumulative 5-year success rate was 93%. The clinical parameters, including the modified plaque index, modified sulcus bleeding index, Jemt’s papilla index, and pink esthetic score improved throughout the 5-year study.ConclusionsThe study demonstrated that narrow-diameter implants represent a safe and predictable treatment option for subjects suitable for immediate loading and with limited bone volume or limited inter-dental space.Clinical relevanceNarrow-diameter implants with immediate provisionalization can be considered for use to restore missing or damaged teeth with predictable functional and esthetic outcomes. This trial was registered with ClinicalTrials.gov (NCT02184845).

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.

Impact of Interproximal Features on Marginal Bone Level Changes of Autograft, Allograft, and Xenograft after Functional Loading: A Retrospective Study

Abstract Aim: This study aims to investigate the marginal bone level changes (MBLCs) concerning interproximal features of posterior implant-supported single crowns using different bone grafts. Materials and Methods: This retrospective study included 27 patients requiring 46 dental implants using autograft, allograft, or xenograft between January 2007 and December 2016. MBLCs were assessed using digital periapical radiographs at 3 months (T1), 12–15 months (T2), and 21–24 months (T3) after prosthesis delivery. The influence of interproximal features, such as embrasure surface area, emergence angle, and horizontal distance to adjacent teeth/implants, was assessed. Secondarily, age, gender, diabetes and smoking, arch distribution, implant locations, implant characteristics, average gonial angle, antagonist type, clinical crown-to-fixture ratio, retention method, and nearby tooth/implant were considered. Wilcoxon signed-rank test, Mann–Whitney U tests, and Kruskal–Wallis tests were employed with statistical significance set at a P value of &lt;0.05. Results: The results revealed that mean MBLCs at T3–T1 were similar (autograft 0.5 ± 0.47 mm, allograft 0.51 ± 0.35 mm, and xenograft 0.57 ± 0.42 mm). There were significant increases in MBLCs associated with EA ≤ 30° in autograft (P = 0.04), and HD ≤ 3 mm in allograft (P = 0.03). Mesial/distal MBLCs showed no significant differences, except in cases with HD ≤ 3 mm in the distal area of autograft (P = 0.03). Regarding secondary factors, significant differences in MBLCs emerged between autograft and xenograft in the molar area (P = 0.03), and between premolar and molar areas within the xenograft group (P = 0.01). Conclusion: This study concludes that interproximal features, EA ≤ 30° and HD ≤ 3 mm, markedly influenced MBLCs for specific types of bone grafts. Furthermore, MBLCs exhibited a direct relationship with the posterior placement of dental implants.

Effect of supracrestal tissue height on marginal bone level changes at platform-switching dental implants placed crestally and subcrestally: A randomized clinical-trial

ObjectivesThe presence of insufficient peri-implant supracrestal tissue height (STH) may increase marginal bone resorption. This study aims to evaluate the effect of STH on marginal bone level changes (ΔMBC) in platform-switching posterior implants placed crestally and subcrestally. MethodsA total of 80 implants were included in this study. There were two main groups in the study; STH≤2 mm (A) and STH> 2 mm (B) and four subgroups according to the implant placement level, crestally (I) and subcrestally (II): A-I, A-II, B-I, and B-II. Intraoperatively, STH and placement depths of implants were measured from mesial and distal aspects. The mesial and distal peri-implant marginal bone levels were measured on periapical radiographs at immediately (T0), 6 months (T1), 9 months (T2), and 12 months (T3) after functional loading, and the difference between the marginal bone levels was calculated as the ΔMBC. ResultsStatistically significantly more mesial ΔMBC was detected in the A-I than in the B-I at the time of T0–T1. In the group with STH greater than 2 mm, the difference in ΔMBC between the crestally and subcrestally placements was not statistically significant. ConclusionsThis study was found that STH is effective at protecting the marginal bone in the early period, and in cases where the STH is insufficient, subcrestally placement may increase long-term implant success by preventing marginal bone loss from occurring beyond the implant shoulder. The clinical trial number is NCT05595746. Clinical significanceIn this study, it was demonstrated that an STH greater than 2 mm is important for marginal bone stabilization, regardless of crestal and subcrestal levels, and that subcrestally placement is beneficial in cases of insufficient STH.

Maxillary and mandibular overdentures retained by two unsplinted narrow-diameter titanium-zirconium implants - Aclinical pilot study.

To evaluate the survival rates and marginal bone loss of narrow-diameter titanium-zirconium implants supporting complete maxillary and mandibular overdentures up to 3 years after loading. Ten completely edentulous patients who were dissatisfied with their complete dentures were enrolled. Two narrow-diameter implants were placed in the canine region of the maxilla and mandible. After second-stage surgery, implant-supported overdentures (palatal-free) attached by parallel alignable stud-attachments were placed. Patients were followed periodically for up to 36 months. Standardized radiographs were taken at baseline, 12 and 36 months to analyze mean marginal bone level changes around the implants. The Kaplan-Meier survival rates were 100% for mandibular and 68.0% (SE ± 10.9%) for maxillary implants at 36 months (p = .008). Six maxillary implants failed after loading; no mandibular implants were lost. Five implants failed due to loss of osseointegration. One implant fractured. The mean marginal bone level changes around the analyzed implants (n = 28, 9 patients) were -0.71 ± 0.82 mm in the mandible and -2.08 ± 1.52 mm in the maxilla at the 36-month follow-up. The difference in marginal bone level changes between the maxilla and mandible was significant (p = .019) at the 12- and 36-month follow-ups. Two narrow-diameter titanium-zirconium implants with stud-attachments showed a highly satisfactory outcome in the mandible. The maxillary implants showed a high failure rate and significantly more bone loss over time than the mandibular implants. The minimal concept of two implants and an overdenture should be limited to the edentulous mandible.

A randomized clinical trial on zirconia versus titanium implants in maxillary single tooth replacement.

This RCT aimed to compare zirconia and titanium dental implants in the maxillary premolar region. The comparison was based on marginal bone level (MBL) changes, clinical parameters, aesthetic outcomes, and patient related outcome measures (PROMs) 1 year after prosthetic loading. Fifty patients were randomly assigned to receive either a zirconia (ZrO2, n = 25) implant or a titanium (Ti, n = 25) bone-level implant. Implants were provided with a lithium disilicate crown 3 months after placement. Follow-up was at 1 month and after 1 year. The primary outcome pertained to changes in MBL. Reported secondary outcomes consisted of implant survival, peri-implant tissue health, aesthetics, and PROMs. Mean MBL change after 1 year was 0.01 mm (SD = 0.45; min = 0.72, max = 0.86) for ZrO2 and -0.09 mm (SD = 0.34; min = 0.53, max = -1.06) for Ti (p = .439). Scores for the other clinical outcome parameters and PROMs were generally favorable, with no significant differences. However, significant differences were found for the aesthetic outcomes regarding two criteria: (a) level of facial mucosa (p = .022), in favor of Ti, and (b) root convexity/soft tissue color and texture (p = .005) in favor of ZrO2. The ZrO2 and Ti implant types used in this study, replacing a single missing maxillary premolar, show a comparable outcome in terms of MBL change after 1 year. Clinical and aesthetic parameters, as well as PROMs, are favorable and similar between both implant types after 1 year of prosthetic loading. These short-term study results suggest that both are suitable for clinical use.