An Implant With an Acid-etched Fixture Surface and Internal-hex Collar May Achieve Greater Osseointegration.

• Sponsor: Université de Montréal (Other)
• Overall Status: Completed
• CT.gov ID: NCT01641198
• Collaborator: Medical Research Council of Canada, FRSQ, CoreVent, Université de Montréal (Other)
• Enrollment: 58
• Location: 1
• Arms: 3
• Actual Duration (Months): 259
• Patients Per Site Per Month: 0.2

Study Details

Study Description

Brief Summary

Brånemark System® dental implant osseointegration was introduced clinically in 1965 as a novel approach to the replacement of missing teeth. Although this implant's traditional machined screw-shaped surface had excellent, well-documented short- and long-term osseointegration success, newer implant designs were introduced that could enhance biological fusion of the implant to jaw bones, allowing more rapid restoration and function. It was also claimed that such implants could lead to less bone loss with function. One such implant, Screw-Vent®, had a macrostructure very similar to that of the Brånemark implant, except that it's fixture surface was acid-etched which could enhance biological osseointegration. It also had a longer narrower smooth internal-hex interlocking flat collar that could better resist occlusal forces, leading to even less bone loss according to the manufacturer. However, no well-controlled clinical studies existed in 1990 that supported these claims. This study was undertaken, therefore, to first compare the Brånemark implant with another implant, Swede-Vent®, a copy of the Brånemark implant except for its fixture surface that was identically acid-etched as that of Screw-Vent by the same manufacturer. The effect on bone healing could then be compared between Brånemark's machined and Swede-Vent's acid-etched surfaces in the short- and long-terms. Our hypothesis was that the microtextured Swede-Vent fixture would lead to greater bone preservation. Since Screw-Vent's fixture surface was identically acid-etched as that of Swede-Vent by the same manufacturer, we could then evaluate the effect on bone healing of Screw-Vent's collar and the shorter wider machined smooth external-hex flat collar of Swede-Vent (identical to that of Brånemark). All three 2-part platform-matched parallel-wall implants were made of commercially pure titanium, had a very similar fixture macro-design, were approved by the Food and Drug Administration (USA) and Health and Welfare Canada, and were commercially available in North America. Brånemark is still available, but with an oxidized microtextured fixture surface and a shortened machined smooth external-hex flat collar. Screw-Vent is still available with its microtextured fixture surface, but its machined smooth internal-hex flat collar has also been substantially shortened. Swede-Vent is no longer available.

Condition or Disease	Intervention/Treatment	Phase
Jaw, Edentulous; Dental Implant	Device: Configuration 1; Device: Configuration 2; Device: Configuration 3	N/A

Detailed Description

This prospective randomized long-term superiority clinical trial tests the hypothesis that an implant with an acid-etched fixture surface and internal-hex machined flat collar results in greater bone preservation.

Age-eligible participants were recruited into this study between 1990 and 1992 from the external clinics of a university dental faculty and hospital affiliated dental department. Study was peer reviewed, had satisfied ethics committee's criteria for human clinical research, and was to take place at the university dental faculty and hospital affiliated department. Sixty participants were enrolled. The study's coordinator evaluated clinical charts to confirm that participants had satisfied the pre-determined inclusion criteria, and that registry operations, data collection, documentation and analysis followed established protocol.

A statistician who was not part of the research team prepared a sampling design that included three Configurations. Each Configuration contained five implants of the three types, thereby allowing an equal number of each implant type to be placed in a cyclical side-by-side rotating fashion at each of five sites between the mental foramen. Consequently, 100 implants of each of the three types were to be placed for a total of 300. However, two participants opted out before start of study so that 58 (30 women) received 290 implants, and each participant acted as their own control. A different identification number was placed on each participant's chart, and allocation concealment then allowed 20 participants to receive Configuration 1, 19 Configuration 2, and 19 Configuration 3. Configuration diagram (but not number) identifying the implant type and length to be placed at each site was stored inside each chart, and only shown to the operating team at surgery. Following restoration with a fixed complete dental prosthesis on the implants, each participant was examined and standardized peri-apical radiographs were taken of each implant after 12 and 24 months and at 15-20 years of function. Distance between first bone-to-implant contact point (fBIC) and crestal abutment-implant interface/microgap (MG) was measured at right and left sides of each abutment-implant surface on the radiographs by examiners who were not part of the research team. Mean fBIC-MG values were then calculated, documented and compared between Brånemark, Swede-Vent and Screw-vent at the three intervals.

Assessment was based on intention to treat. Inter and intra-examiner reliability of measurements was assessed using Intraclass Correlation Coefficient and Bland-Altman Repeatability. Statistical analysis was based on the mixed linear model that included fixed effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect). Position and time were repeated within participants, and Shapiro-Wilk Test was applied to verify that data was following normal distribution. Bonferroni correction was used for pairwise comparisons, and a p value of <0.05 was considered significant. Confidence Interval was established at 2-sided 95% Confidence Level. All statistical analyses were performed using Statistical Package for the Social Sciences (SPSS) Version 23® (IBM Corp, Armonk US).

The following were consulted in order to utilize standardized descriptive terms.

American Society of Anesthesiologists Physical Status Classification System (1963) was used to classify each participant's physical health as Class 1 (obligatory).

Lekholm-Zarb Classification System (1987) was used to classify each participant's quality (density) of mandibular bone as Types 2 and 3 (obligatory).

Salzman Skeletal Bone Intermaxillary Classification System (1966) was used to classify each participant's profile skeletal relationship between maxilla and mandible as Class 1 (obligatory).

American Psychological Association (APA) Publication Manual (2001, fifth edition, Washington, DC) was used to describe certain participant baseline demographic characteristics.

Study Design

• Study Type: Interventional
• Actual Enrollment: 58 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
• Primary Purpose: Treatment
• Official Title: Prospective Randomized Clinical Trial Comparing Quantitative Osseous Healing of Acid Etched and Machined Titanium Implant Fixtures After 12 and 24 Months, and at 15-20 Years of Function With Full Arch Fixed Mandibular Prostheses.
• Actual Study Start Date: Mar 1, 1992
• Actual Primary Completion Date: Mar 24, 1998
• Actual Study Completion Date: Sep 30, 2013

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Configuration 1 Device placement: B (Brånemark) at two sites, SW (Swede-Vent) at two sites, SC (Screw-Vent) at one site	Device: Configuration 1; B placed at sites 2 and 5, SW placed at sites 1 and 4, SC placed at site 3
Experimental: Configuration 2 Device placement: B (Brånemark) at one site, SW (Swede-Vent) at two sites, SC (Screw-Vent) at two sites	Device: Configuration 2; B placed at site 3, SW placed at sites 2 and 5, SC placed at sites 1 and 4
Experimental: Configuration 3 Device placement: B (Brånemark) at two sites, SW (Swede-Vent) at one site, SC (Screw-Vent) at two sites	Device: Configuration 3; B placed at sites 1 and 4, SW placed at site 3, SC placed at sites 2 and 5

Outcome Measures

Primary Outcome Measures

1. Comparison of Quantitative Bone Healing [After 12 months of function]

   Distance between first bone-to-implant contact point (fBIC) and microgap (MG) placed at the crest was measured at the right and left sides of each implant-abutment complex on periapical radiographs taken of each implant. Measurements were taken and recorded after 12 months of function. Mean fBIC-MG values were calculated, recorded and compared between B and SW, between B and SC and between SW and SC for Configuration 1, Configuration 2 and Configuration 3

2. Comparison of Quantitative Bone Healing [After 24 months of function]

   Distance between first bone-to-implant contact point (fBIC) and microgap (MG) placed at the crest is measured at the right and left sides of each implant-abutment complex on periapical radiographs taken of each implant. Measurements were taken and recorded after 24 months of function. Mean fBIC-MG values were calculated, recorded and compared between B and SW, between B and SC and between SW and SC for Configuration 1, Configuration 2 and Configuration 3

3. Comparison of Quantitative Bone Healing [At 15-20 years of function]

   Distance between first bone-to-implant contact point (fBIC) and microgap (MG) placed at the crest is measured at the right and left sides of each implant-abutment complex on periapical radiographs taken of each implant. Measurements were taken and recorded at 15 to 20 years of function. Mean fBIC-MG values were calculated, recorded and compared between B and SW, between B and SC and between SW and SC for Configuration 1, Configuration 2 and Configuration 3

Eligibility Criteria

Criteria

• Ages Eligible for Study: 25 Years to 56 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

No systemic disease (ASA Class 1)

Aged between 25 and 56 years

Non-smoking

No Temporomandibular Joint (TMJ) disorder or other facial pain

Wearing of complete maxillary and mandibular removable prostheses for at least one year

Skeletal Class 1 inter-maxillary relationship

Type 2 and/or Type 3 mandibular bone quality

Possess at least 1 cm of bone height between the superior and inferior cortical tables and at least 6 mm of bucco-lingual bone width between mental foramen

Specifically requesting a fixed full arch dental prosthesis over the implants and a conventional full arch removable maxillary prosthesis

Accepting to sign informed consent documents.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Université de Montréal	Montreal	Quebec	Canada	H3C 3J7

Sponsors and Collaborators

• Université de Montréal
• Medical Research Council of Canada, FRSQ, CoreVent, Université de Montréal

Investigators

• Principal Investigator: Patrice Milot, DMD,MSD, Université de Montréal
• Principal Investigator: Hugo Ciaburro, DMD, MSc, Université de Montréal
• Principal Investigator: Aldo-Joseph Camarda, DDS, MSc, Université de Montréal

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Aldo Joseph Camarda, Associate Professor, Université de Montréal
• ClinicalTrials.gov Identifier: NCT01641198
• Other Study ID Numbers: 12-069-CERES-D
• First Posted: Jul 16, 2012
• Last Update Posted: Dec 17, 2020
• Last Verified: Dec 1, 2020

• Individual Participant Data (IPD) Sharing Statement: No
• Plan to Share IPD: No
• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: Yes
• Product Manufactured in and Exported from the U.S.: Yes
• Keywords provided by Aldo Joseph Camarda, Associate Professor, Université de Montréal: Dental Implants Microtextured Fixture Machined Collar Bone
• Additional relevant MeSH terms: Jaw, Edentulous

Study Results

Participant Flow

Recruitment Details	Recruitment period: 1990 - 1992
Pre-assignment Detail	Sixty participants were recruited; however, two participants opted out prior to informed consent and random assignment to an arm.

Arm/Group Title	Configuration 1	Configuration 2	Configuration 3
Arm/Group Description	Surgical placement of devices (implants): B at sites 2 and 5, SW at sites 1 and 4, SC at site 3	Surgical placement of devices (implants): B at site 3, SW at sites 2 and 5, SC at sites 1 and 4	Surgical placement of devices (implants): B at sites 1 and 4, SW at site 3, SC at sites 2 and 5
Period Title: After 12 Months of Function
STARTED	20	19	19
COMPLETED	16	16	17
NOT COMPLETED	4	3	2
Period Title: After 12 Months of Function
STARTED	16	16	17
COMPLETED	12	7	11
NOT COMPLETED	4	9	6
Period Title: After 12 Months of Function
STARTED	12	7	11
COMPLETED	6	6	9
NOT COMPLETED	6	1	2

Baseline Characteristics

Arm/Group Title	Configuration 1	Configuration 2	Configuration 3	Total
Arm/Group Description	Surgical placement of devices (implants): B at sites 2 and 5, SW at sites 1 and 4, SC at site 3	Surgical placement of devices (implants): B at site 3, SW at sites 2 and 5, SC at sites 1 and 4	Surgical placement of devices (implants): B at sites 1 and 4, SW at site 3, SC at sites 2 and 5	Total of all reporting groups
Overall Participants	20	19	19	58
Overall Implants	100	95	95	290
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	45.3 (5.3)	45.5 (5.6)	44.8 (6.1)	45.2 (5.6)
Sex: Female, Male (Count of Participants)
Female	10 50%	10 52.6%	10 52.6%	30 51.7%
Male	10 50%	9 47.4%	9 47.4%	28 48.3%
Region of Enrollment (Count of Participants)
Canada	20 100%	19 100%	19 100%	58 100%
Number of Participants with Health Status ASA Classification 1 (Count of Participants)
Count of Participants [Participants]	20 100%	19 100%	19 100%	58 100%
Number of Participants with Mandibular bone classification types 2 & 3 (Count of Participants)
Count of Participants [Participants]	20 100%	19 100%	19 100%	58 100%
Removable complete dental prostheses obligatory (Count of Participants)
Count of Participants [Participants]	20 100%	19 100%	19 100%	58 100%
Specifically requesting a complete lower prosthesis on implants (Count of Participants)
Count of Participants [Participants]	20 100%	19 100%	19 100%	58 100%
Accepting to sign informed consent documents (Count of Participants)
Count of Participants [Participants]	20 100%	19 100%	19 100%	58 100%

Outcome Measures

1. Primary Outcome

Title	Comparison of Quantitative Bone Healing
Description	Distance between first bone-to-implant contact point (fBIC) and microgap (MG) placed at the crest was measured at the right and left sides of each implant-abutment complex on periapical radiographs taken of each implant. Measurements were taken and recorded after 12 months of function. Mean fBIC-MG values were calculated, recorded and compared between B and SW, between B and SC and between SW and SC for Configuration 1, Configuration 2 and Configuration 3
Time Frame	After 12 months of function

Outcome Measure Data

Analysis Population Description

Reasons for decrease in population number: 7 did non-respect interval follow up protocol, 1 adverse event, 1 protocol violation. Reasons for decrease in number of units (implants): radiographs did not allow precise location of first bone-to-implant contact point (fBIC) and microgap (MG) due to technical reasons for 19 implants

Arm/Group Title	Configuration 1	Configuration 2	Configuration 3
Arm/Group Description	Surgical placement of devices (implants): B at sites 2 and 5, SW at sites 1 and 4, SC at site 3	Surgical placement of devices (implants): B at site 3, SW at sites 2 and 5, SC at sites 1 and 4	Surgical placement of devices (implants): B at sites 1 and 4, SW at site 3, SC at sites 2 and 5
Measure Participants	16	16	17
Measure Implants.	67	77	82
Mean (Standard Error) [mm]	-1.18 (0.15)	-1.01 (0.16)	-0.91 (0.17)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between B and SW estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.29
	Confidence Interval	(2-Sided) 95%; -0.59 to 0.01
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.115
	Estimation Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between B and SC estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.39
	Confidence Interval	(2-Sided) 95%; 0.09 to 0.69
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.12
	Estimation Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between SW and SC estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.685
	Confidence Interval	(2-Sided) 95%; -0.98 to -0.39
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.115
	Estimation Comments

2. Primary Outcome

Title	Comparison of Quantitative Bone Healing
Description	Distance between first bone-to-implant contact point (fBIC) and microgap (MG) placed at the crest is measured at the right and left sides of each implant-abutment complex on periapical radiographs taken of each implant. Measurements were taken and recorded after 24 months of function. Mean fBIC-MG values were calculated, recorded and compared between B and SW, between B and SC and between SW and SC for Configuration 1, Configuration 2 and Configuration 3
Time Frame	After 24 months of function

Outcome Measure Data

Analysis Population Description

Reasons for decrease in the number of participants: 19 did not respect follow up interval. Reasons for decrease in number of units (implants): radiographs did not allow precise location of first bone-to-implant contact point (fBIC) and microgap (MG) due to technical reasons for 5 implants

Arm/Group Title	Configuration 1	Configuration 2	Configuration 3
Arm/Group Description	Surgical placement of devices (implants): B at sites 2 and 5, SW at sites 1 and 4, SC at site 3	Surgical placement of devices (implants): B at site 3, SW at sites 2 and 5, SC at sites 1 and 4	Surgical placement of devices (implants): B at sites 1 and 4, SW at site 3, SC at sites 2 and 5
Measure Participants	12	7	11
Measure implants	57	35	53
Mean (Standard Error) [mm]	-1.16 (0.18)	-0.87 (0.23)	-1.33 (0.18)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between B and SW estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.17
	Confidence Interval	(2-Sided) 95%; -0.47 to 0.13
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.135
	Estimation Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between B and SC estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.56
	Confidence Interval	(2-Sided) 95%; 0.26 to 0.85
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.13
	Estimation Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between SW and SC estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.725
	Confidence Interval	(2-Sided) 95%; -1.02 to -0.43
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.135
	Estimation Comments

3. Primary Outcome

Title	Comparison of Quantitative Bone Healing
Description	Distance between first bone-to-implant contact point (fBIC) and microgap (MG) placed at the crest is measured at the right and left sides of each implant-abutment complex on periapical radiographs taken of each implant. Measurements were taken and recorded at 15 to 20 years of function. Mean fBIC-MG values were calculated, recorded and compared between B and SW, between B and SC and between SW and SC for Configuration 1, Configuration 2 and Configuration 3
Time Frame	At 15-20 years of function

Outcome Measure Data

Analysis Population Description

Reasons for decrease in the number of participants: 7 did not respect follow up interval, 2 unrelated deaths

Arm/Group Title	Configuration 1	Configuration 2	Configuration 3
Arm/Group Description	Surgical placement of devices (implants): B at sites 2 and 5, SW at sites 1 and 4, SC at site 3	Surgical placement of devices (implants): B at site 3, SW at sites 2 and 5, SC at sites 1 and 4	Surgical placement of devices (implants): B at sites1 and 4, SW at site 3, SC at sites 2 and 5
Measure Participants	6	6	9
Measure implants	30	30	45
Mean (Standard Error) [mm]	-1.32 (0.27)	-1.42 (0.33)	-1.54 (0.33)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between B and SW estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.20
	Confidence Interval	(2-Sided) 95%; -0.19 to 0.59
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.20
	Estimation Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between B and SC estimated with the mixed linear model (mean±SE, 95% CI)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.83
	Confidence Interval	(2-Sided) 95%; 0.45 to 1.22
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.20
	Estimation Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Configuration 1, Configuration 2, Configuration 3
	Comments	Mean bone change between SW and SC estimated with the mixed linear model (mean±SE, 95% CI).
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	Statistical analysis was based on the mixed linear model with the level of significance set at p<0.05 and Bonferroni correction for pairwise comparisons
	Method	Mixed Models Analysis
	Comments	Mixed linear model with effects of time, implant position, implant configuration, implant type (and implant length as a covariate effect)
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.635
	Confidence Interval	(2-Sided) 95%; -1.01 to -0.26
	Parameter Dispersion	Type: Standard Error of the Mean; Value: 0.20
	Estimation Comments

Adverse Events

Time Frame	Adverse data collection after 12 and 24 months, and 15-20 years of function
Arm/Group Title	Configuration 1		Configuration 2		Configuration 3
Arm/Group Description	Surgical placement of devices (implants): B at sites 2 and 5, SW at sites 1 and 4, SC at site 3		Surgical placement of devices (implants): B at site 3, SW at sites 2 and 5, SC at sites 1 and 4		Surgical placement of devices (implants): B at sites 1 and 4, SW at site 3, SC at sites 2 and 5
All Cause Mortality
	Configuration 1		Configuration 2		Configuration 3
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	1/20 (5%)		0/19 (0%)		1/19 (5.3%)
Serious Adverse Events
	Configuration 1		Configuration 2		Configuration 3
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/20 (0%)		1/19 (5.3%)		0/19 (0%)
Musculoskeletal and connective tissue disorders
Loss of jaw implant	0/20 (0%)	0	1/19 (5.3%)	1	0/19 (0%)	0
Other (Not Including Serious) Adverse Events
	Configuration 1		Configuration 2		Configuration 3
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/20 (0%)		0/19 (0%)		0/19 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.