Wear Characteristics and Clinical Performance of Lithium Silicate Versus Monolithic Zirconia Crowns.

January 2, 2019 updated by: Rasmia Mamdouh Ali Salem, Cairo University

Wear Characteristics and Clinical Performance of Lithium Silicate Versus Monolithic Zirconia Crowns. (Randomized Controlled Clinical Trial)

The aim of the present study is to evaluate the wear characteristics and clinical performance of lithium silicate crowns in comparison to monolithic zirconia crowns.

The quality of the overall restorations as well as gingival tissues will be also evaluated according to modified United States Public Health Service (USPHS) criteria: (Marginal adaptation, color match, anatomic form, integrity of restoration, secondary caries, retention, tooth sensitivity, gingival index and periodontal index) at baseline, 6 months and 1 year

Study Overview

Status

Unknown

Conditions

Intervention / Treatment

Detailed Description

Recently advances in ceramics have greatly improved the mechanical and optical properties of restorative materials to overcome the drawbacks of all ceramic restorations over decades such as fracture, chipping, crack, wear and delamination of veneer ceramics.

Up to date despite the popularity of all ceramic restoration, the clinicians have been worried about the wear of tooth enamel antagonist to ceramic materials.

The wear properties of the ceramic restoration can affect the rate of wear of the antagonist enamel. So the wear resistance of ceramic restoration must be the same as enamel.

Explanation for choice of the comparator:

Monolithic zirconia attracts many dentists worldwide due to its excellent mechanical properties, biocompatibility and appreciate aesthetics. Some in vivo studies demonstrated the clinical success of monolithic zirconia restorations as an antagonist to natural enamel with good marginal adaptation, accepted contour, occlusion and minimum gingival response.

Batson et al. studied the quality of CAD/CAM fabricated single tooth restorations (Ten zirconia restorations were compared to 12 metal ceramic and 10 lithium disilicate counterparts) .They found that were no significant differences between the studied crown systems. No difference of the gingival response among the different crown systems. Eighty percent of zirconia crowns needed no occlusal adjustment; also it showed the least amount of marginal discrepancy.

Lohbauer et al. evaluated the amount of wear on the antagonist occlusal surfaces of clinically placed monolithic zirconia premolar and molar crowns using optical profilometry after 2 years of cementation, they found that the mean volume loss for enamel antagonist contacts (n = 7) was measured to 361 μm and the mean of the maximum vertical loss to 204 μm. The mean volume loss for pure ceramic contacts (n = 10) was measured to 333 μm and the mean of the maximum vertical loss to 145 μm.

Mundhe et al.compared the wear of enamel opposing polished zirconia, glazed metal ceramic crowns and natural enamel as a control, one year after the cementation. They found that the occlusal wear of the antagonistic enamel one year after the cementation of metal ceramic crowns ranged from 69.20 ± 4.10 to 179.70 ± 8.09 μm, whereas, for zirconia crowns, it was from 42.10 ± 4.30 to 127.00 ± 5.03 μm.

Stober et al. reported that after 2 years of cementation of the monolithic zirconia crowns, Mean and maximum vertical loss of enamel in occlusal contact areas caused by monolithic zirconia (46 and 151 μm, respectively) was approximately double that caused by contralateral antagonistic enamel (19-26 and 75-115 μm, respectively).

A lithium silicate glass ceramic (obsidian ceramic) is newly introduced to the market. After crystallization, it exhibits an ideal combination of esthetics and strength with translucency that mirrors the vitality of natural teeth for fabrication of full anatomic anterior and posterior crowns. Obsidian ceramic restorations are highly resistant to chipping unlike other ceramics, due to their monolithic composition and average flexural strength of 385 MPa. Also Obsidian Milling Block owes its good wear resistance due to a very high content of ultrafine nanometer-size crystalline structure.

Study Type

Interventional

Enrollment (Anticipated)

22

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Egypt
      • Giza, Egypt, 12613
        • Cairo University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

21 years to 50 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • All subjects are required to be:

    1. Age range of the patients from 21-50 years old; able to read and sign the informed consent document, illiterate patient will be avoided.
    2. Patients able physically and psychologically to tolerate conventional restorative procedures.
    3. Patients with no active periodontal or pulpal diseases, having teeth with good restorations.
    4. Patients with teeth problems indicated for full coverage restoration (e.g. moderate to severe discoloration, coronal fracture where partial coverage would lack retention, malposed or malformed teeth).
    5. Patients with root canal treated teeth requiring full coverage restorations.
    6. Presence of an opposing natural tooth which is non-restored or minimally restored. (Minimally restored is defined as teeth which have no restoration greater than a Class II a restoration)
    7. The opposing arch doesn't have a full coverage restoration or a partial denture.

    8. Patients willing to return for follow-up examinations and evaluation.

      Exclusion Criteria:

    1. Patients with poor oral hygiene.
    2. Patients with psychiatric problems or unrealistic expectation (patient that has phobia from dental treatments or needle bunch).
    3. Patients have no opposite occluding dentition in the area intended for restoration
    4. Patients suffer from Para functional habits or temporomandibular disorders. (as those patient may have wear which will affect the results)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: monolithic zirconia crowns
Monolithic zirconia attracts many dentists worldwide due to its excellent mechanical properties, biocompatibility and appreciate aesthetics
Other: monolithic zirconia crowns
full anatomical monolithic crowns
Other Names:
  • katana zirconia, Kuraray Noritake , Japan
Experimental: lithium silicate crowns
A lithium silicate glass ceramic is newly introduced to the market. After crystallization, it exhibits an ideal combination of aesthetics and strength with translucency that mirrors the vitality of natural teeth for fabrication of full anatomic anterior and posterior crowns.
Other: lithium silicate crowns
lithium silicate glass ceramics are highly resistance to chipping
Other Names:
  • obsidian, Glide well Laboratories, USA

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Wear of all ceramic crowns and color matching
Time Frame: 12 month
(Wear of ceramic crowns) of the two groups will be assessed using the 3D optical profilometer.
12 month
color matching
Time Frame: 12 month

Color match of the two groups will assessed using the modified United States public health service (USPHS) criteria as follows:

  • Alpha (Excellent) ideal.
  • Bravo (Acceptable) less than ideal but no modifications required
  • Charlie (Acceptable but modifications needed) staining or other shade modifications required.
  • Delta (Unacceptable) remake.
12 month

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Wear of enamel antagonist to all ceramic crowns
Time Frame: 12 month
wear of antagonist enamel of the two groups will be assessed using the 3D optical profilometer.
12 month
Marginal adaptation
Time Frame: 12 month

of the two groups will assessed using the modified United States public health service (USPHS) criteria as follows:

  • Alpha (Excellent) ideal.
  • Bravo (Acceptable) less than ideal but no modifications required
  • Charlie (Acceptable but modifications needed) modifications required.
  • Delta (Unacceptable) remake.
12 month
anatomic form
Time Frame: 12 month

of the two groups will assessed using the modified United States public health service (USPHS) criteria as follows:

  • Alpha (Excellent) ideal.
  • Bravo (Acceptable) less than ideal but no modifications required
  • Charlie (Acceptable but modifications needed) modifications required.
  • Delta (Unacceptable) remake.
12 month
integrity of restoration
Time Frame: 12 month

of the two groups will assessed using the modified United States public health service (USPHS) criteria as follows:

  • Alpha (Excellent) ideal.
  • Bravo (Acceptable) less than ideal but no modifications required
  • Charlie (Acceptable but modifications needed) modifications required.
  • Delta (Unacceptable) remake.
12 month
secondary caries
Time Frame: 12 month

of the two groups will assessed using the modified United States public health service (USPHS) criteria as follows:

  • Alpha (Excellent) ideal.
  • Bravo (Acceptable) less than ideal but no modifications required
  • Charlie (Acceptable but modifications needed) modifications required.
  • Delta (Unacceptable) remake.
12 month
retention
Time Frame: 12 month

of the two groups will assessed using the modified United States public health service (USPHS) criteria as follows:

  • Alpha (Excellent) ideal.
  • Bravo (Acceptable) less than ideal but no modifications required
  • Charlie (Acceptable but modifications needed) modifications required.
  • Delta (Unacceptable) remake.
12 month
opposing tooth sensitivity
Time Frame: 12 month

of the two groups will assessed using the modified United States public health service (USPHS) criteria as follows:

  • Alpha (Excellent) ideal.
  • Bravo (Acceptable) less than ideal but no modifications required
  • Charlie (Acceptable but modifications needed) modifications required.
  • Delta (Unacceptable) remake.
12 month
gingival condition
Time Frame: 12 month
Gingival index by Visual inspection using Score from 0-3
12 month
periodontal condition
Time Frame: 12 month
Periodontal index by Periodontal probe using Score from 0-4
12 month

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Cairo University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Anticipated)

February 1, 2019

Primary Completion (Anticipated)

December 1, 2019

Study Completion (Anticipated)

February 1, 2020

Study Registration Dates

First Submitted

May 7, 2018

First Submitted That Met QC Criteria

May 17, 2018

First Posted (Actual)

May 21, 2018

Study Record Updates

Last Update Posted (Actual)

January 3, 2019

Last Update Submitted That Met QC Criteria

January 2, 2019

Last Verified

January 1, 2019

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • enamel and ceramics wear

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe