Aim of the study :

to compare between 3D printed microfilled hybrid composite endocrowns and prefabricated
zirconia crowns for restoring pulpally treated primary molars regarding the following
aspects: In Vivo aspects Patient satisfaction

*The esthetic, functional and biological performance according to FDI clinical criteria.
At 3, 6 and 12 months

In Vitro aspects:

  -  Marginal gap.

  -  Fracture resistance.

Study methodology:

This study is a combined randomized clinical trial and in vitro study .The study will be
conducted at the Department of Pediatric Dentistry and Dental Public Health, Faculty of
Dentistry,

Ain Shams University as follows:

In vivo comparison of the clinical performance of 3D printed Endocrowns versus
prefabricated zirconia crowns regarding esthetic, functional and biological performance
according to FDI clinical criteria. In vitro evaluation of the marginal gap and fracture
resistance of both types of restorations.

3D-printed Endocrowns Versus Prefabricated Zirconia Crowns in Pulpally-treated Primary Molars

Pulpotomy

Tooth Restoration

Study Procedure:

In-vivo Phase:

Study Population:

A total of thirty primary mandibular molars in healthy subjects will be selected from the
Pediatric Dentistry and Dental Public Health outpatient clinic, Faculty of Dentistry, Ain
Shams University. Randomization The molars will be assigned to one of the 2 groups using
a generated computer list Allocation The molars will be allocated to the groups via a
third party not involved with the study They will have the generated list and inform the
allocation accordingly Blinding Is not possible due to the obvious difference between the
2 Pulpotomy procedure for both groups:

  1. Local anesthesia will be administered.

  2. Teeth will be isolated by a Rubber Dam.

  3. Teeth will undergo pulpotomy procedure' as follows:

Caries will be removed using a large size 4 round bur, mounted onto a high speed hand
piece with constant coolant. All access cavity walls are to be flared to allow complete
exposure of the pulp chamber, and easy undisturbed access to the canals, followed by
removal of all the soft pulpal tissue tags by a sharp spoon shaped excavator. Bleeding
will be controlled using moist cotton pellet with gentle pressure. Formocresol will be
applied through a cotton pellet for 5 mins, for fixation. The pulp chamber will be filled
with reinforced zinc oxide and eugenol ( that will be mixed according to manufacturer s
instructions. A 0.5 mm layer of Resin modified glass ionomer is then applied to the
cavity floor and light cured for 40 secs, to isolate the zinc oxide eugenol paste, and
block unwanted undercuts Analgesics will be prescribed to the patient to be taken when
needed

Intervention :group A:

  1. The cavities will be prepared so as to receive endocrowns:

     Occlusal preparation: achieved by drilling, 2mm depth grooves using diamond stone as
     guides for reduction of the occlusal surface. axial preparation: using a 7 degree
     taper diamond stone, eliminating undercuts in the access cavity.

  2. impression for the preparation is taken using putty and light poly vinyl siloxane
     material

  3. Light cured temporary filling will be placed in the cavity as temporisation.

  4. The impression will be sent to the lab and the patient is dismissed

  5. The preparation will be optically scanned in the lab and the restoration will be
     digitally designed using computer designing software.

  6. The restoration will be printed using 3D printer using microfilled hybrid composite
     material.

  7. During the second visit the temporary is removed the restoration is cemented by self
     adhesive resin after etching and bonding the cavity.

Control Group B:

  1. Crown reduction:

     reduction will be performed on the occlusal surface disregarding the occlusal
     anatomy using a flame stone or a wheel stone, to perform occlusal clearance. Then
     reduction will be performed on the mesial, distal, buccal and lingual surfaces of
     the tooth to compensate for the thickness of the zirconia crowns. Reduction will
     first be performed using fine needle stone to free the contact from the adjacent
     teeth then followed by reduction of the other surfaces using a diamond stone.
     Roundation of the line angles will be performed

  2. Zirconia crowns that match the size of the tooth will be selected putting into
     consideration that no undercuts should be present to avoid crown fracture.

  3. . After checking the size of the crowns, it will be removed, drie d and cemented on
     the tooth using (3M™ ESPE™ KETAC™ CEM) that will be mixed according to
     manufacturer's instructions.

  4. Pressure will be applied on the crown, and any excess cement will be removed after
     it hardens. All children and parents will be give n strict oral hygiene instructions
     and dietary instructions Teeth not included in the study will be scheduled for
     dental treatment in the Department of Pediatric Dentistry, Faculty of Dentistry, Ain
     Shams University. Outcome measurement

Esthetic functional biological criteria will be evaluated in the following order:

After cementation evaluation: patients will be evaluated according to FDI criteria as
previously mentioned,.

In Vitro phase:

All soft tissue debris will be removed by a hand scaler and teeth will be disinfect ed,
and then stored in distilled water at 4 degrees Celsius until the start of the study.

The molars will undergo pulpotomy procedures and filled as previously described. The
molars will be randomly divided into two groups Group A: Will receive 3D printed
Endocrowns Group B: Will receive prefabricated zirconia crowns The specimens will be
embedded perpendicularly in Polyvinyl chloride ( cubes with the occlusal surface parallel
to the ground using acrylic resin extending 2mm b elow the cemento enamel junction. The
following will be measured: Marginal gap Precementation measurements of the cervical
vertical marginal discrepancies will be performed before cementation. For each specimen,
four stereomicrographs will be captured by a stereomicroscope (Wild 400, Switzerland) at
a 32× magnification. Images will then be transferred to the computer software for image
analysis

Fracture Resistance:

An axial loading condition through the functional cusp will be defined in the mechanical
failure description. Failure to fracture strength will be tested with a universal testing
machine at a 0.5 mm/sec crosshead speed. Application of a round end vertical loading tip
on the occlusal third of a specimen fixed into a loading apparatus as functional loading
simulation.

Data Management:

Patient information will be gathered and stored in the patient examination chart of the
outpatient clinic, Department of Pediatric Dentistry, faculty of Dentistry, Ain Shams
University. All information will be kept as a hard copy and as an electronic one as well.
Patient information will be guarded as co nfidential information that should never be
revealed at all times. This file will remain with the investigator during the study.

Statistical Analysis:

All data will be tabulated, summarized and statistically analyzed using software SPSS
(Statistical Packages for Social Sciences. 3 and 6 months evaluation: evaluation of the
previous criteria.

3D-printed endocrown

Zirconia crown

3D-printed Endocrowns Versus Prefabricated Zirconia Crowns for the Restoration of Pulpally-treated Primary Molars ; In-Vivo and In-Vitro Study

Federation Dentaire international clinical assessment scale. Minimum value is 1 and
highest value is 11. Higher values mean worst outcome.

principal investigator

A structured patient satisfaction questionnaire with a 3 points likert scale question.

3D printed microfilled hybrid composite Endocrowns

3D-printed Endocrowns Versus Prefabricated Zirconia Crowns in Pulpally-treated Primary Molars

About this trial

Study ID

Status

Type

Phase

Placebo

Accepting

Trial Timing

What is this trial about?

What are the participation requirements?

Locations

Location

Status