One-year results of a clinical and radiological prospective multicenter study on NEOSS® dental implants

Do dental implants installed in different types of bone (I, II, III, IV) have different success rates? A systematic review and meta-analysis

Purpose

The objective of this systematic review and meta-analysis was to evaluate the survival rate of implants installed in bone type IV (Lekholm and Zarb, 1995) compared to that of implants installed in bone types I, II, and III.

Material and methods

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA) and was registered in the PROSPERO International Database of Systematic Reviews (CRD42021229775). The PubMed/MEDLINE, Scopus, and Cochrane databases were searched through July 2021. The PICO question was: "Dental implants installed in type IV bone have a lower success rate when compared to implants installed in type I bone, II and III?". The established inclusion criteria were: 1) controlled and randomized clinical trials (RCT), 2) prospective and retrospective studies with at least 10 participants with dental implants, and 3) patients with dental implants installed in bone tissue types I, II, III, and IV (Lekholm and Zarb, 1985). The minimum followup duration was 1 year.

Results

After searching the identified databases, 117 articles were selected for full reading and 68 were excluded. Thus, 49 studies were included for qualitative and quantitative analyses. The total number of participants included was 12,056, with a mean age of 41.56 years and 29,905 implants installed. Bone types I, II, and III exhibit a lower implant failure rate when compared to bone type IV.

Conclusion

Dental implants installed in bone types I, II, and III showed significantly higher survival rates than those installed in type IV. The bone type I success rate was not significantly different than that of type II; however, the success rate of bone type I and II was higher than that of type III.

A Simplified Prosthetic Implant Loading Protocol: 1-Year Clinical Follow-Up Study

Purpose

To retrospectively investigate the one-year clinical outcome following a standardized treatment protocol for immediate loading. The protocol mandates predefined requirements for implant stability. If fulfilled, immediate loading of the implants is performed with a simplified prosthetic protocol which includes one-time impression at the time of surgery and definitive restoration within eight weeks.

Methods

Twenty-five patients were treated with 48 Neoss ProActive Tapered implants. Minimum primary stability was established before subjecting the implants to immediate nonfunctional load. Definitive prostheses were delivered six to eight weeks from implant placement. Insertion torque (IT), resonance frequency analysis (RFA), intraoral radiographs, and impressions of implant positions were registered at implant placement. During clinical follow-up, RFA was measured at two, four, and six to eight weeks and six months from implant placement to monitor continued implant stability. Marginal bone level measurements were performed at implant placement, six-month, and one-year follow-up visits.

Results

IT was over 40 N·cm for 46 implants. Two implants with IT <30 N·cm were both splinted to another implant with IT >50 N·cm, tightening the retention screw with low forces. No implants were lost during the observation period. Mean RFA measurements remained stable without any decrease during the initial six-month healing phase. Mean marginal bone remodeling was −0.47 ± 0.38 mm from implant placement to 1 year. No significant difference was found for marginal bone remodeling between implants placed in the healed bone or fresh extraction sockets.

Conclusion

Within the limits of this study, it is concluded that using a simplified immediate loading protocol can be predictably applied to reduce the overall treatment time and the number of clinical sessions.

Clinical and Patient-Related Outcomes of a Tapered Implant System With Switched Platform Conical Abutments: A Private Practice Field Trial

The aim of this prospective cohort observational field trial was to examine 1-year survival and success rates of a recently introduced tapered implant system with switched platform conical abutments and to evaluate patient related outcomes of therapy. Partially edentulous patients aged between 18 and 75 years, with available bone height for dental implants ≥10 mm desiring to restore the missing tooth/teeth with implant supported restoration, were recruited by 7 periodontists in their respective private practices. Dental implants were installed according to standard implant therapy protocol. Three to 6 months postoperatively, after evaluating interim implant success, implants were restored by the referring dentists. Patient, Ramfjord teeth, and implant data, including baseline and 1-year postoperative, were collected. A total of 60 patients were recruited and received 117 implants. Complete 1-year clinical and radiographic data were available for 83 and 65 implants, respectively. Two implants failed during the first year, resulting in a 1-year survival rate of 98.3%. Mean implant probing pocket depth was 2.29 ± 0.84 mm. Mean radiographic bone distance from implant's shoulder at the mesial and distal sites at 1 year was 0.66 ± 0.5 and 0.79 ± 0.64mm, respectively, resulting in a success rate of 95.4%. Patient subjective evaluation of therapy exhibited a median pain experience of 1 and median esthetics, function, and general satisfaction evaluation of 10 on a scale of 1 to 10. The tapered conical connection dental implant system, used in private dental practices, shows good 1-year survival and success rates that are similar to other implant systems on the market.

A One-year Follow-up Study of a Tapered Hydrophilic Implant Design Using Various Placement Protocols in the Maxilla

Purpose:

To study the clinical/radiographic outcomes and stability of a tapered implant design with a hydrophilic surface when placed in the maxilla using various protocols and followed for one year.

Methods:

Ninety-seven consecutive patients treated as part of daily routine in two clinics with 163 tapered implants in healed sites, in extraction sockets and together with bone augmentation procedures in the maxilla were evaluated after one year in function. Individual healing periods varying from 0 to 6 months had been used. Insertion torque (IT) and resonance frequency analysis (RFA) measurements were made at baseline. Follow-up RFA registrations were made after 6 and 12 months of loading. The marginal bone levels were measured in intraoral radiographs from baseline and after 12 months. A reference group consisting of 163 consecutive straight maxillary implants was used for the comparison of baseline IT and RFA measurements.

Results:

Five implants failed before loading, giving an implant survival rate of 96.9% and a prosthesis survival rate of 99.4% after one year. The mean marginal bone loss after one year was 0.5 mm (SD 0.4). The mean IT was statistically significantly higher for tapered than for straight reference implants (41.3 ± 12.0 Ncm vs 33.6 ± 12.5 Ncm, p < 0.001). The tapered implants showed a statistically insignificantly higher mean ISQ value than the straight references implants (73.7 ± 6.4 ISQ vs 72.2 ± 8.0 ISQ, p=0.119). There was no correlation between IT and marginal bone loss. There was a correlation between IT and RFA measurements (p < 0.001).

Conclusion:

The tapered implant showed a high survival rate and minimal marginal bone loss after one year in function when using various protocols for placement. The tapered implant showed significantly higher insertion torque values than straight reference implants.

A Randomized Case-Series Study Comparing the Stability of Implant with Two Different Surfaces Placed in Fresh Extraction Sockets and Immediately Loaded

Background. Hydrophilic and moderately rough implant surfaces have been proposed to enhance the osseointegration response. Aim. The aim of this study was to compare early changes of stability for two implants with identical macrodesign but with different surface topographies. Materials and Methods. In 11 patients, a total of 22 implants (11 bimodal (minimally rough, control) and 11 proactive (moderately rough and hydrophilic, test), Neoss Ltd., Harrogate, UK) were immediately placed into fresh extraction sockets and immediately loaded. The peak insertion torque (IT) was measured in Ncm at placement. Resonance Frequency Analysis (RFA) measurements were made at baseline and 2, 4, 6, and 12 weeks after surgery. Results. The two implant types showed similar IT and RFA values at placement (NS). A dip of RFA values after 2 weeks followed by an increase was observed, where the test implant showed a less pronounced decrease and a more rapid recovery than the control implant. The test implants were significantly more stable than the control ones after 12 weeks. Conclusions. The results from the present study indicated that the hydrophilic and rougher test implant was more resistant to immediate loading and showed a significantly higher stability than the smoother control implant after 12 weeks.

A Retrospective Study on Immediate Placement of Neoss Implants with Early Loading of Full-Arch Bridges

BACKGROUND

Full-arch clearances of compromised teeth and placement of implant-supported prostheses is one solution for the prosthetic rehabilitation of partially dentate patients.

PURPOSE

To retrospectively evaluate treatment outcomes after full clearance, immediate placement, and early loading of full-arch fixed bridges.

MATERIALS AND METHODS

Fifty-five patients subjected to full clearance and placement of 284 Neoss implants (Bimodal™ and Proactive™, Neoss Ltd, Harrogate, UK) in 29 edentulous maxillae and 26 mandibles for early loading (1 to 3 days) of a provisional full-arch bridge were retrospectively evaluated after 1 to 6 years of loading. Osstell™ measurements (Osstell AB, Göteborg, Sweden) were taken at placement and after 3 to 9 months when the provisional bridge was replaced with a permanent one. Marginal bone levels were measured in intraoral radiographs.

RESULTS

All patients (100%) wore a fixed bridge at the time of finalizing the study. A total of 18 failures (6.3%) were encountered during the follow-up, giving an overall cumulative survival rate of 93.7%. All failures occurred in the maxilla (10.6%), and no implants were lost in the mandible. More Bimodal™ (9.0%) than Proactive™ (4.1%) implants failed. Failing implants showed a significantly lower mean primary stability than successful ones (p = .015). Failed cases showed a significantly lower average ISQ for all implants (p = .015) and a marked decrease to the second registration, while successful cases showed and maintained high ISQs. The average bone loss after 1 year was 0.8 ± 0.5 mm.

CONCLUSIONS

Full-arch clearance of severely diseased teeth followed by immediate placement of Neoss implants, early loading with provisional full-arch bridges, and subsequent permanent bridges is a possible treatment modality for partially dentate patients. Caution with this approach is recommended for the maxilla, as opposed to the mandible.