Condition category
Surgery
Date applied
15/04/2008
Date assigned
31/07/2008
Last edited
31/07/2008
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information

Type

Scientific

Primary contact

Prof Ralph Luthardt

ORCID ID

Contact details

Center of Dentistry
Department of Prosthetic Dentistry
Albert-Einstein-Allee 11
Ulm
89081
Germany

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

P-10199 CR 04/05

Study information

Scientific title

Clinical trial of the influence of time on the three-dimensional accuracy of fast-set polyether and fast-set polyvinyl siloxane impression materials

Acronym

Poly Q

Study hypothesis

Clinical studies have shown a correlation between the fitting precision of fixed dental restorations and the clinical success or survival rate. Since dental impressions mainly determine the fitting precision of fixed restorations, they play an important role. So far, the working times of impression materials have only been evaluated in-vitro. In the clinical routine, deviations from the exact timing occur very often and are either caused by an early filling of the impression tray by the dental assistance or by a delay during syringing of the light-body impression material. The clinical relevance of the exact timing gains even more importance when fast-setting impression materials with shorter working times and setting times are used.

A non-optimal timing will have an influence on the three-dimensional precision of fast-set impressions materials. Due to the kinetics of their chemical reaction, polyethers may be of advantage compared to polyvinyl siloxane impression materials.

Ethics approval

Ethics approval received from the Ethics Commission of the Medical Faculty Carl Gustav Carus of the Technical University Dresden on the 11th August 2004 (ref: EK 180092004)

Study design

Pilot study and prospective, randomised clinical trial with triple-blind evaluation

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Other

Trial type

Treatment

Patient information sheet

Patient information material can be found at: http://www.uniklinik-ulm.de/fileadmin/Kliniken/Zahnmedizin/ZMK2/SIMTOM/20040726_Patienteninfo_PolyQ_SQ.pdf (in German)

Condition

Fitting precision of fixed dental restorations

Intervention

The study gains information on the dependency between mixing timing of a one-stage putty-and-wash dental impression and three-dimensional precision of the resulting gypsum models under clinical conditions. Differences between two types of fast-set impression materials (polyether and polyvinyl siloxane) are to be analysed with a computer-aided procedure.

Three impressions were taken from the probands, after they had undergone a professional tooth cleaning, in randomised order. Either a polyether impression or a polyvinyl siloxane impression were taken under exact timing conditions and served as a reference. Two additional impressions were taken with non-optimal timing using the same impression material as for the respective reference impression. The two additional impressions were taken with two out of eight different non-optimal timings. The order in which the three impressions were taken as well as the material and the non-optimal timing were assigned to each proband according to a randomisation list. Standardised-made master-casts were digitised and the data resulting from the non-optimal timed impressions was compared to the reference. Probands were treated with fluoride gel afterwards in order to complete the benefit of the professional tooth cleaning.

Intervention type

Drug

Phase

Not Specified

Drug names

Polyether, polyvinyl siloxane

Primary outcome measures

The precision of the three-dimensional (3D) tooth surface reproduction and the reproduction of the subgingival tooth surface, measured within 24 hours after impression taking.

Secondary outcome measures

1. Influence of environment temperature, measured in the impression session
2. Timing, measured in the impression session
3. Tray size, measured in the impression session
4. Accordance with subjective clinical impression rating, measured within four weeks after the impression session has taken place, throughout the study

Overall trial start date

01/08/2004

Overall trial end date

31/03/2006

Reason abandoned

Eligibility

Participant inclusion criteria

Suitable probands were aged between 18 and 80 years, either sex, and showed a complete set of either healthy or restored teeth in the lower right quadrant up to the second molar.

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

8 for pilot study, 96 for main study

Participant exclusion criteria

1. Alcohol or drug dependence
2. Persons with restricted legal capacity
3. Pregnant women
4. Probands who would face a conflict of interest due to the participation in another study
5. Patients with periodontal disease (periodontal screening index greater than 2)
6. Probands with missing teeth in the according quadrant (except for third molars and orthodontically closed spaces)
7. Probands excluded from the dental education course because of an infectious disease such as hepatitis or acquired immune deficiency syndrome (AIDS)

Recruitment start date

01/08/2004

Recruitment end date

31/03/2006

Locations

Countries of recruitment

Germany

Trial participating centre

Center of Dentistry
Ulm
89081
Germany

Sponsor information

Organisation

3M ESPE AG (Germany)

Sponsor details

Dr Timo Kuretzky
Espe Platz
Seefeld
82229
Germany
+49 (0)8152 700 1376
timo.kuretzky@mmm.com

Sponsor type

Industry

Website

http://www.3mespe.com

Funders

Funder type

Industry

Funder name

M ESPE AG (Germany) (ref: P 10 244 CR 04/01.04.04)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes