The Influence of the Crown-implant Ratio on the Crestal Bone Level and Implant Secondary Stability

Not Applicable

Completed

• Conditions: Tooth Loss; Partial Edentulism
• Interventions: Other: Short implants Treatment; Other: Regular implants Treatment

• Registration Number: NCT03471000
• Lead Sponsor: Jakub Hadzik

Brief Summary

The aim of the study was to determine whether implant length and the crown-to-implant (C/I) ratio influence implant stability and the loss of the surrounding marginal bone, and whether short implants can be used instead of sinus augmentation procedures.

Detailed Description

The patients participating in the study (n=30) had one single tooth implant - a short (OsseoSpeed™ L6Ø4 mm, Implants) or a regular implant (OsseoSpeed™ L11 and L13Ø4 mm, DENTSPLY Implants) - placed in the maxilla. The evaluation was based on clinical and radiological examination.

The crown-to-implant ratio was determined by dividing the length of the crown together with the abutment by the length of the implant placed crestally. Mean crown-to-implant ratios were calculated separately for each group and its correlation with the MBL (marginal bone loss) and stability was assessed. The authors compared the correlation between the C/I ratio values, MBL and secondary implant stability.

Study Timeline

• Study Start: 2012-01-01
• Primary Completion: 2016-01-01
• Study Completion: 2016-01-01
• Study First Submitted: 2018-03-05
• Study First Submitted QC: 2018-03-13
• Study First Posted: 2018-03-20
• Status Verified: 2020-01
• Last Update Submitted: 2020-01-11
• Last Update Posted: 2020-01-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• Non-smoking patients with no systemic or local diseases were qualified.

Additional inclusion criteria were as follows:

• minimal apicocoronal height of the alveolar ridge of 6 mm in the region of the implant insertion in the pre-surgical qualification
• minimal width of the alveolar ridge of 6-7 mm in the region of interest
• HKT (height of the keratinized tissue) higher than 2 mm
• API ≤ 35 (Approximal Plaque Index)
• PI ≤ 25. (Plaque Index)
• Bone Type III or D2 were included in the study
• No graft procedures in the area of interest,

Exclusion Criteria

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Short implants Treatment	Short implants Treatment	Group 2 (G2; n=15 patients) had short implants (OsseoSpeed ™ L6mm Ø4 mm) \[DENTSPLY Implants, Waltham, MA, USA\] placed without sinus lift and augmentation procedure.
Regular Implants Treatment	Regular implants Treatment	Group 1 (G1; n=15 patients) had conventional dental implants (OsseoSpeed ™ L11 Ø4 mm and L13 Ø4 mm) \[DENTSPLY Implants, Waltham, MA, USA\] placed, preceded by the sinus lift procedure from a lateral window approach with the application of the xenogeneic bone graft Geistlich Bio-Oss® \[Geistlich AG, Wolhusen, Switzerland\]. The lateral window approach sinus lift surgery was performed 6 weeks prior to the implant placement by the same surgeon.

Primary Outcome Measures

Name	Time	Method
Clinical measurement of implant stability	36 months	Evaluation of implant secondary stability in both groups. Stability measured and evaluated with Periotest(R) device - after 36 months.

Secondary Outcome Measures

Name	Time	Method
Radiological measurement of marginal bone loss around implant	36 months	Evalation if there is difference in marginal bone level around the implants in both groups. Periapical radiographs and CBCT images taken and the begining and at the end of the observation period will be compared and bone level will be measured. Loss of marginal bone will be calculated.