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Trial record 7 of 119 for:    ZIRCONIUM

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

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ClinicalTrials.gov Identifier: NCT03530020
Recruitment Status : Not yet recruiting
First Posted : May 21, 2018
Last Update Posted : January 3, 2019
Sponsor:
Information provided by (Responsible Party):
Rasmia Mamdouh Ali Salem, Cairo University

Brief Summary:

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


Condition or disease Intervention/treatment Phase
Enamel and Ceramics Wear Other: monolithic zirconia crowns Other: lithium silicate crowns Not Applicable

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.


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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 22 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Patient will receive a restoration with superior function, esthetics, and excellent clinical performance.
Masking: Double (Participant, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Wear Characteristics and Clinical Performance of Lithium Silicate Versus Monolithic Zirconia Crowns. (Randomized Controlled Clinical Trial)
Estimated Study Start Date : February 1, 2019
Estimated Primary Completion Date : December 1, 2019
Estimated Study Completion Date : February 1, 2020

Resource links provided by the National Library of Medicine


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 Name: 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 Name: obsidian, Glide well Laboratories, USA




Primary Outcome Measures :
  1. 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.

  2. 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.


Secondary Outcome Measures :
  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. gingival condition [ Time Frame: 12 month ]
    Gingival index by Visual inspection using Score from 0-3

  9. periodontal condition [ Time Frame: 12 month ]
    Periodontal index by Periodontal probe using Score from 0-4



Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


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Ages Eligible for Study:   21 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

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)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03530020


Contacts
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Contact: rasmia salem, msc 01024340442 rasmia.salem@yahoo.com

Locations
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Egypt
Cairo university Not yet recruiting
Giza, Egypt, 12613
Contact: Rasmia M salem, msc    01024340442    rasmia.salem@yahoo.com   
Contact: Gihan El Nagar, professor       drgigielnagar@yahoo.com   
Principal Investigator: Gihan el nagar, professor         
Sub-Investigator: Maha Taymour, Ass. Professor         
Sponsors and Collaborators
Cairo University

Publications:

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Responsible Party: Rasmia Mamdouh Ali Salem, principal investigator, Cairo University
ClinicalTrials.gov Identifier: NCT03530020     History of Changes
Other Study ID Numbers: enamel and ceramics wear
First Posted: May 21, 2018    Key Record Dates
Last Update Posted: January 3, 2019
Last Verified: January 2019

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Rasmia Mamdouh Ali Salem, Cairo University:
monolithic zirconia
tooth wear
all ceramic crown
Additional relevant MeSH terms:
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Lithium Carbonate
Antidepressive Agents
Psychotropic Drugs
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Antimanic Agents
Tranquilizing Agents
Central Nervous System Depressants
Physiological Effects of Drugs