Marginal Integrity and Clinical Evaluation of Polyetheretherketone (PEEK) Versus Lithium Disilicate (E-max) Endocrowns.

Study Overview
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Brief Summary
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Patients need Endocrowns for their teeth usually use Emax as an etchable ceramic. Yet they have disadvantages that may influence the outcome of the endocrowns, among which is the high stiffness and rigidity owing to the higher modulus of elasticity (67.2 GPa)( compared to natural dentin (18.6 GPa) which may affect the marginal adaptation.so a less rigid material is needed. PEEKs (polyetheretherketones) are presented as alternative materials to metal and glass ceramics, Their elastic modulus comparable to those of cortical bone and dentin so the polymer could exhibit good stress distribution. Also they have high fracture resistance, and low abrasion to the antagonist enamel. .but the investigators have to know clinically it is performance , so the investigators are going to have Parallel groups in a randomized clinical trial.

Official Title
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Marginal Integrity and Clinical Evaluation of Polyetheretherketone (PEEK) Versus Lithium Disilicate (E-max) Endocrowns.

Conditions
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Endodontically Treated Teeth

Intervention / Treatment
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* Other: PEEK
* Other: Emax


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All subjects are required to be: From 18-60 years old, and able to read and sign the informed consent document. Physically and psychologically able to tolerate conventional restorative procedures Have no active periodontal or pulpal diseases. Willing to return for follow-up examinations and evaluation Exclusion Criteria: Patients in the growth stage with partially erupted teeth Patient with fractured teeth of more than 50% enamel loss Patients with poor oral hygiene and motivation Pregnant women Psychiatric problems or unrealistic expectations Lack of opposite occluding dentition in the area intended for restoration

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PEEK<br>PEEKs (polyetheretherketones) are presented as alternative materials to metal and glass ceramics,1 Their elastic modulus comparable to those of cortical bone and dentin so the polymer could exhibit good stress distribution. Also they have high fracture resistance, and low abrasion to the antagonist enamel. Yet clinical studies are needed to evaluate their clinical performance. | Other: PEEK<br>* New polyetheretherketones material<br>* Other names: BioHPP polyetheretherketones;|
| Active Comparator: Emax<br>lithium disilicate glass-ceramic which is etchable and proved to have good success rate if used for Endocrowns | Other: Emax<br>* standard etchable glass ceramic used for Endocrowns<br>* Other names: lithium disilicate glass ceramic;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| evaluation of marginal gap | Marginal gap of the restorations assessed by Silicon replica technique using digital microscope | through study completion, an average of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical evaluation of marginal adaptation | Marginal adaptation of the restorations assessed clinically using dental mirror and probe according to the modified united states public health service criteria (USPHS) | 1 Year | 
| Clinical evaluation of fracture resistance | Fracture resistance of the restorations assessed clinically using dental mirror and probe according to the modified united states public health service criteria (USPHS) | 1 Year |