Custom-made Zirconia Crowns Versus Prefabricated Zirconia Crowns in Young Permanent Molars

Custom-made Zirconia Crowns Versus Prefabricated Zirconia Crowns in Young Permanent Molars: A Randomised Controlled Trial

This study aims to compare the clinical performance of Prefabricated Zirconia Crowns (PZCs) with that of Custom-made Zirconia Crowns (CZCs) using enhanced clinical protocols.

Study Overview

• Status: Enrolling by invitation
• Conditions: Zirconia Crowns
• Intervention / Treatment: Procedure: Prefabricated Zirconia Crown; Procedure: Custom-made Zirconia Crowns

Detailed Description

Young permanent molars presenting with gross caries, pulpal treatment or developmental defects often require full coverage restorations. Recently, the Prefabricated Zirconia Crowns (PZCs) have been introduced as a biocompatible and an aesthetically pleasant option with promising outcomes. However, it comes in specific sizes, limited shades and a significant tooth preparation is often required. Custom-made zirconia crowns (CZCs), fabricated using CAD/CAM technology may; offer a favorable aesthetic alternative by ensuring a controlled tooth reduction, precise fit, better aesthetics, and improved retention. Nevertheless, the current evidence concerning its use in young permanent molars remains limited. This study will be a randomised clinical trial that aims to compare the clinical performance of (PZCs) with that of (CZCs) for the restoration of badly carious/destructed young permanent molars in children aged 7-13. Patients will be randomised into two treatment groups using an online block randomisation technique (block size of 6) and sealed-envelope techniques. Clinical parameters: retention, fracture, gingival health and marginal integrity will be evaluated at 3-month, 6-month, and 12-month intervals. In addition, treatment duration, intraoperative patient comfort and immediate postoperative patient satisfaction will be evaluated and compared. The findings of this study are expected to provide evidence on the suitability of CZC for young permanent molars in children. The Null hypothesis is that there is no difference between the two types of crowns in terms of clinical performance and child acceptance.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Jordan
  • Irbid, Jordan
    • Jordan University of Science and Technology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Medically fit or with mild systemic illness (ASA I or II).
• Children who assent to take part in the study with a valid parental consent
• Children who have at least one first permanent molar requiring a full-coverage restoration (indications for placing a crown include: badly destructed/carious molars, or teeth affected by molar-incisor hypomineralisation (MIH))
• Maxillary or mandibular fully erupted first permanent molars, regardless of the stage of root development.
• A cooperative child that accepts dental treatment (Frankle Behaviour Rating Scale #3 or 4).
• Capable of attending all follow-up sessions.

Exclusion Criteria:

• Patients outside the required age range
• Parents/child not willing to participate.
• Medically compromised patients
• Partially erupted permanent first molars.
• Patients with severe malocclusion that prohibits the provision of crowns
• First permanent molars are not indicated for full coverage restorations.
• First permanent molars are indicated for extraction.
• Patients with bruxism or parafunctional habits.
• Uncooperative children (Frankle Behaviour Rating Scale #1 or 2)

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Prefabricated Zirconia Crowns; Tooth preparation and cementation of a suitable size of prefabricated Zirconia crown.	Procedure: Prefabricated Zirconia Crown; Tooth preparation as per the manufacturer's instructions and cementation of a suitable size of prefabricated Zirconia crown using self-adhesive resin cement.
Experimental: Custom-made Zirconia Crowns; Tooth preparation, followed by oral scanning and production and cementation of a zirconia crown using CAD-CAM technology.	Procedure: Custom-made Zirconia Crowns; Tooth preparation (1-1.5 mm occlusal, 0.5 to 1.25 mm circumferential, with a shoulder-edge supra-gingival margin), followed by scanning with an intra-oral scanner, then temporisation. A zirconia crown will be produced using CAD-CAM technology and cemented with a self-adhesive resin cement on a different visit.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of Crown retention	Visual-tactile evaluation of the crown retention over time (crown present, loose or lost).	3,6 and 12 months
Rate of chipping and fracture of the crown	Clinical evaluation for the presence/absence of crown chipping or fracture	3,6 and 12 months
Gingival health	Clinical evaluation of the gingival inflammation ( the gingival index (GI) by Löe & Silness 1963 )	3,6 and 12 months
Clinical crown margin extension	Visual-tactile evaluation for crown margin extension (supra/ equi/sub-- gingival)	3,6 and 12 months
Radiographic crown margin adaptation	Evaluation of crown margin adaptation (Geduk et al., 2023)	6 and 12 months
Clinical crown margin adaptation	Clinical evaluation of crown margin using an explorer (Geduk et al., 2023)	3,6 and 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time taken for intervention	Total time taken to perform the intervention for each crown (crown preparation, try-in and cementation) in minutes.	Perioperative/Periprocedural: from the beginning of tooth preparation and until the crown is cemented.
Patient satisfaction	Self-reported child acceptance using a 5-points visual analogue scale	immediately following intervention.
Patient's comfort	will be evaluated by an observer (research assistant who will be trained, and calibrated) and recorded using the Sound, Eyes, and motor scale (SEM); Based on the intensity of the child's discomfort, each parameter is scored into one of four categories (comfort (score 0), mild discomfort (score 1), moderately painful (score 2), and painful (score 3)). The total score can range from 0 to 9, with 9 indicating the highest level of discomfort.	peri-operatively

Collaborators and Investigators

• Sponsor: Jordan University of Science and Technology

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2025
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2027

Study Registration Dates

• First Submitted: March 25, 2026
• First Submitted That Met QC Criteria: July 9, 2026
• First Posted (Actual): July 15, 2026

Study Record Updates

• Last Update Posted (Actual): July 15, 2026
• Last Update Submitted That Met QC Criteria: July 9, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Children; Zirconia crowns; Prefabricated Zirconia crowns; Custom-made Zirconia crowns; Young permanent molars
• Other Study ID Numbers: 245-2025

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No