Custom-made Versus Prefabricated Zirconia Crowns for Primary Molars.
Condition: Decayed Teeth
MeSH terms: Dental Caries
Study type: Interventional

Summary: 
      Background: Do construction methods of pediatric zirconia crowns affect the periodontal
      health and clinical performance of badly decayed primary molars? The question asked by many
      practitioners.

      Purpose: to compare the periodontal health and clinical performance of primary molars
      restored with custom-made and prefabricated zirconia crowns. Hypothesis is the performance of
      primary molars restored with custom-made zirconia crowns will be equivalent to those restored
      with prefabricated zirconia crowns.
    

Detailed description: 
      This study is a randomized, 12-month follow up clinical trial. According to sample size
      calculation, ten patients will be selected in conjunction with departments of Pedodontics and
      Crowns & Bridges. The study will be conducted in accordance with the principles of the
      Research Ethics Committee, Faculty of Dental Medicine for Girls, Al-Azhar University, Egypt.

      The purpose of the investigation and the clinical procedures of this study will be explained
      to the parents and children. A written informed consent form will be signed from patient
      guardians and obtained prior to study initiation. The inclusion and exclusion criteria are
      established as the following;

        -  Inclusion criteria

             1. Children of 5-9 years old.

             2. The children have at least 2 pulpotomized primary molars with no clinical signs &
                symptoms or periapical pathosis.

             3. Presence of an intact contralateral primary molar as a control.

             4. Willingness to participate and to continue with the follow up appointments.

             5. Clinical and radiographically confirmed dental caries extending to the middle third
                of dentin.

             6. Presence of teeth in opposite arch with normal occlusion.

        -  Exclusion criteria

             1. Children with systemic health problem.

             2. Children with periodontal disease.

             3. Children with unilateral chewing habit or allergic to local anesthesia.

             4. Presence of parafunctional habit.

        -  Clinical procedure;

             1. Patient selection and education; The participating children will continue with
                their routine dental appointments in the undergraduate training clinic. Before
                beginning, children, along with their parents will receive a standard oral hygiene
                education by an undergraduate student through brushing demonstration on a model.
                Parents will be warned when signs of gingival inflammation are present, or plaque
                control is inadequate.

             2. Samples grouping and teeth preparation:

                Forty primary molars will be included in the study. Twenty decayed teeth will be
                restored with crowns (10 with custom-made ZrCs and 10 with prefabricated ZrCs), and
                the other twenty intact contralateral teeth will be evaluated as the controls (10
                molars will be the controls for custom-made ZrCs and 10 molars will be the controls
                for prefabricated ZrCs). Preparation of the crowns will be performed under local
                anesthesia, according to manufacturers' instructions with the following guidelines;
                1-2mm occlusal reduction, 0.5-1mm axial reduction, and a chamfer finish line will
                be established 0.5-1mm subgingivally.

             3. Impression taking and temporization:

                After preparation, rubber-base impressions will be taken for the teeth specific for
                custom-made ZrCs. Then SSCs will be temporarily cemented over the prepared teeth
                till the next appointment.

             4. Try-in and cementation of ZrCs:

                SSCs will be removed and the custom-made and prefabricated ZrCs will be tried in
                and permanently cemented.

        -  Follow-up visits:

      The participants will be recalled for evaluation after a baseline and at 1, 3, 6 and 12
      months.

      • Evaluation methods:

        1. The periodontal health will be assessed using the plaque index (PI) and the gingival
           index (GI).

        2. The clinical success of the crowns will be assessed in terms of crown retention,
           marginal adaptation, crown contour, fracture, stain resistance, opposing tooth wear and
           tooth exfoliation.
    

Intervention name(s): Custom-made zirconia crowns; Prefabricated zirconia crowns
Intervention type(s): Other; Other
Intervention description(s): Ten decayed primary molars will be restored with custom-made zirconia crowns.; Ten decayed primary molars will be restored with prefabricated zirconia crowns.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Three groups will be included;
Custom-made Zirconia Crowns Group (10 molars)
Prefabricated Zirconia Crowns Group (10 molars)
Masking: Single (Participant)
Primary purpose: Health Services Research
Keywords: Zirconia Crown, Primary teeth