Short vs Long Dental Implants for the Fixed Rehabilitation of the Fully Edentulous Mandible

Short vs Long Implants Supporting a Total Fixed Prosthetic Rehabilitation of the Fully Edentulous Mandible. A Multicenter Randomized Controlled Clinical Trial

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03509402

Enrollment

Registered

2018-04-26

Start date

2010-01-31

Completion date

2021-02-28

Last updated

2025-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Edentulous Jaw

Keywords

short dental implants, full-arch prosthesis

Brief summary

The aim of this study is to clinically and radiographically compare the performance of short (6 mm-long) versus long (≥11 mm-long) dental implants placed in the interforaminal region of fully edentulous mandibles, supporting a screw-retained full-arch cantilever bridge.

Detailed description

The use of short dental implants provides undeniable benefits in sites where the reduced available volume would otherwise need bone augmentation procedures and their use has greatly expanded in the recent years. However, well designed clinical trials which provide a sound evidence of their performance and reliability are still lacking to date. In this post-market, multi-center, open, parallel-group, randomized, controlled clinical trial the investigators aim to to clinically and radiographically compare the performance of short (6 mm-long) versus long (≥11 mm-long) dental implants supporting a mandibular screw-retained full-arch cantilever bridge. Five 4mm-wide/6mm-long (test) or 4mm-wide/≥11mm-long (control) titanium dental implants (Osseospeed™, ASTRA TECH Implant System™, Dentsply Sirona) are placed in the interforaminal region of fully edentulous mandibles, in non-regenerated sites, with at least 1 mm of peri-implant bone circumferentially. All products are CE (European Conformity) marked and used within their intended use. Two-Stage surgery is performed, implants are positioned in healed bone and exposed after 3 months to be connected with the prosthesis. This is a medium-term follow-up study including evaluations also at 1 and 3 years from the baseline. Three italian centers participate: Naples (University of Campania Luigi Vanvitelli), Naples (AORN A. Cardarelli), Catania (Private Office). The study protocol has been approved by the Institutional Review Board of the University of Campania Luigi Vanvitelli.

Interventions

DEVICEASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: 6 mm

Rehabilitation of the edentulous mandible by a full-arch srew-retained prosthesis with distal cantilevers supported by five interforaminal short implants (ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: 6 mm)

DEVICEASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: ≥11mm

Rehabilitation of the edentulous mandible by a full-arch srew-retained prosthesis with distal cantilevers supported by five interforaminal long implants (ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: ≥11mm)

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

SINGLE (Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 75 Years

Healthy volunteers

Inclusion criteria

* total edentulous patients in the lower region since at least 8 months, * sufficient amount of native bone (no augmentation procedures) in the recipient sites to allow ≥11 mm long and 4 mm wide implant installation (≥1 mm of peri-implant bone circumferentially) * systemic health * compliance with good oral hygiene * informed consent signed.

Exclusion criteria

* any disease, medication or drug that could jeopardize healing, osseointegration or treatment outcome, * untreated caries or periodontitis of the remaining teeth, * mucosal and bone tissue lesions, * severe bruxism or other parafunction habits, * unrealistic aesthetic demands, * patient taking part to another study

Design outcomes

Primary

Measure	Time frame	Description
Marginal Bone Level (MBL) Change	5 years from baseline (prosthetic loading)	Marginal bone level (MBL) is measured as the distance in millimiters calculated on periapical radiographs from the implant neck to the most coronal bone-to-implant contact point at both the mesial and the distal side of each implant. The radiographs will be taken with an X-ray apparatus supplied with a long cone and Rinn's film holders.

Secondary

Measure	Time frame	Description
Implant Survival Rate	5 years from baseline (prosthetic loading)	A surviving implant is defined as an implant in place at the time of the follow-up. Any implant loss shall be assessed as an early loss (implant fails before being osseointegrated) or late loss (after being osseointegrated).
Prosthesis Survival	5 years from baseline (prosthetic loading)	A surviving prosthesis is defined as still in place at the time of the follow-up.
Biological Complications	5 years from baseline (prosthetic loading)	Peri-implant mucositis and peri-implantitis
Technical Complications	5 years from baseline (prosthetic loading)	Technical complications are categorized in minor and major complications. The formers require only chair-side repair and include screw loosening and veneer material fracture. The latters require additional laboratory procedures and/or replacement components and include prosthesis or framework fracture, screw fracture, implant fracture, and extended wear requiring veneer renewal.

Participant flow

Participants by arm

Arm	Count
Short Implants A full-arch screw-retained mandibular prosthesis with distal cantilevers supported by five interforaminal short implants (ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: 6mm) ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: 6 mm: Rehabilitation of the edentulous mandible by a full-arch srew-retained prosthesis with distal cantilevers supported by five interforaminal short implants (ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: 6 mm)	15
Long Implants A full-arch srew-retained mandibular prosthesis with distal cantilevers supported by five interforaminal short implants (ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: ≥11mm) ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: ≥11mm: Rehabilitation of the edentulous mandible by a full-arch srew-retained prosthesis with distal cantilevers supported by five interforaminal long implants (ASTRA TECH Implant System, OsseoSpeed™ 4.0 S, length: ≥11mm)	15
Total	30

Baseline characteristics

Characteristic	Short Implants	Long Implants	Total
Age, Continuous	63 years STANDARD_DEVIATION 6.3	61 years STANDARD_DEVIATION 8.6	63 years STANDARD_DEVIATION 7.5
Race (NIH/OMB) American Indian or Alaska Native	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Asian	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Black or African American	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) More than one race	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) White	15 Participants	15 Participants	30 Participants
Region of Enrollment Italy	15 participants	15 participants	30 participants
Sex: Female, Male Female	10 Participants	3 Participants	13 Participants
Sex: Female, Male Male	5 Participants	12 Participants	17 Participants
Smoking habit	3 Participants	4 Participants	7 Participants

Adverse events

Event type	EG000 affected / at risk	EG001 affected / at risk
deaths Total, all-cause mortality	0 / 15	0 / 15
other Total, other adverse events	0 / 15	0 / 15
serious Total, serious adverse events	0 / 15	0 / 15

Outcome results

Primary

Marginal Bone Level (MBL) Change

Marginal bone level (MBL) is measured as the distance in millimiters calculated on periapical radiographs from the implant neck to the most coronal bone-to-implant contact point at both the mesial and the distal side of each implant. The radiographs will be taken with an X-ray apparatus supplied with a long cone and Rinn's film holders.