Effect of Crown Material on Gingival Microbial Colonization

Effect of Crown Material on Gingival Microbial Colonization: A Randomized Clinical Trial

• Prior approval from SOD ethical committee has been received.
• All patients presenting to the General OPD of School of Dentistry, Islamabad will be screened. Those patients who fulfill the criteria will be referred to the Prosthodontics department.
• The patients will undergo detailed history and oral examination after informed consent (Annexure-A). Patients will undergo radiographic investigation and based on this information they will be selected for the study according to the exclusion and inclusion criteria.

• Eligible participants will be randomly assigned to one of the following groups using a computer-generated sequence with allocation concealment via sealed opaque envelopes:

  • Group A: Control group
  • Group B: Full-coverage PFM crowns
  • Group C: Full-coverage Zirconia crowns
• Baseline gingival samples will be collected with the help of sterile swab from the target tooth region prior to prosthesis placement and at the follow-up visits i.e. 1, and 3 months; both for experimental groups and control group.
• Microbial analysis will be conducted through culture techniques to quantify CFUs and identify species.
• A summary of the micro-organisms, their incubation media, temperature and time is presented in the following table:

Table 1: Summary of the micro-organisms, their incubation media, temperature and time Micro-organism Growth Media Temperature Incubation time Candida albicans Saboraud Agar 370C 24-48 hours Streptococcus mutans BHI broth 370C 24-48 hours Staphylococcus aureus BHI broth 370C 24-48 hours Porphyromonas gingivalis BHI broth 370C 18-24 hours

• Alongside, the same sample from sterile swabs will be smeared by fixating it on a microscopic slide and then Candida albicans will be stained by Periodic Acid Schiff technique, and the bacterial species using Gram staining.
• All participants will receive standardized verbal and written instructions oral hygiene instructions to control for hygiene-related variation

Study Overview

• Status: Not yet recruiting
• Conditions: Microbial Colonization; Missing Teeth
• Intervention / Treatment: Other: Experimental

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Fatima Nasir Cheema, BDS, Post graduate Resident; Phone Number: +923227965188; Email: fatimanasir969@gmail.com
• Study Contact Backup: Name: Maria Shakoor Abbasi, BDS, FCPS; Phone Number: +923333615061; Email: maria_shakoor@hotmail.com

Study Locations

• Pakistan
  • Federal
    • Islamabad, Federal, Pakistan, 44000
      • School of Dentistry, SZAMBU
      • Contact: Maria Shakoor Abbasi, BDS, FCPS; Phone Number: +923333615061; Email: maria_shakoor@hotmail.com
      • Contact: Fatima Nasir Cheema, BDS, Post graduate resident; Phone Number: 03227965188; Email: fatimanasir969@gmail.com
      • Principal Investigator: Fatima Nasir Cheema, BDS, Post graduate resident

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age between 20 to 50 years.
• Both male and female patients will be selected.
• Good oral hygiene (Defined as a plaque index score ≤ 1 across all assessed surfaces and no visible calculus deposits)
• Dentate patients require fixed prostheses for the first time on mandibular pre-molars and molars.
• Patient with no history of any dental and bony pathosis (cysts, cancerous lesion).

Exclusion Criteria:

• Untreated periodontal diseases
• Xerostomia
• Pregnancy, lactation
• Smokers
• Individuals with systemic conditions like diabetes and immunosuppressive diseases

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Group A: Control group; Same tooth on the contra lateral side
Experimental: Group B: Full-coverage PFM crowns; Microbial analysis will be carried out around the PFM crowns	Other: Experimental; Eligible participants will be randomly assigned to one of the following groups using a computer-generated sequence with allocation concealment via sealed opaque envelopes:Group A: Control groupGroup B: Full-coverage PFM crownsGroup C: Full-coverage Zirconia crowns; Baseline gingival samples will be collected with the help of sterile swab from the target tooth region prior to prosthesis placement and at the follow-up visits i.e. 1, and 3 months; both for experimental groups and control group.; Microbial analysis will be conducted through culture techniques to quantify CFUs and identify species.; Alongside, the same sample from sterile swabs will be smeared by fixating it on a microscopic slide and then Candida albicans will be stained by Periodic Acid Schiff technique, and the bacterial species using Gram staining.
Experimental: Group C: Full-coverage Zirconia crowns; Microbial analysis will be carried out around the Full-coverage Zirconia crowns	Other: Experimental; Eligible participants will be randomly assigned to one of the following groups using a computer-generated sequence with allocation concealment via sealed opaque envelopes:Group A: Control groupGroup B: Full-coverage PFM crownsGroup C: Full-coverage Zirconia crowns; Baseline gingival samples will be collected with the help of sterile swab from the target tooth region prior to prosthesis placement and at the follow-up visits i.e. 1, and 3 months; both for experimental groups and control group.; Microbial analysis will be conducted through culture techniques to quantify CFUs and identify species.; Alongside, the same sample from sterile swabs will be smeared by fixating it on a microscopic slide and then Candida albicans will be stained by Periodic Acid Schiff technique, and the bacterial species using Gram staining.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Quantitative change in gingival microbial count (CFU/ml) for each microorganism over time.	3 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Comparative analysis of microbial colonization trends between PFM and Zirconia crown groups	3 months

Collaborators and Investigators

• Sponsor: Pakistan Institute of Medical Sciences

Study record dates

Study Major Dates

• Study Start (Estimated): August 15, 2025
• Primary Completion (Estimated): December 15, 2025
• Study Completion (Estimated): December 15, 2025

Study Registration Dates

• First Submitted: July 16, 2025
• First Submitted That Met QC Criteria: July 16, 2025
• First Posted (Actual): July 24, 2025

Study Record Updates

• Last Update Posted (Actual): July 24, 2025
• Last Update Submitted That Met QC Criteria: July 16, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases; Pathologic Processes; Disease Attributes; Tooth Diseases; Stomatognathic System Abnormalities; Congenital Abnormalities; Tooth Abnormalities; Infections; Communicable Diseases; Tooth Loss; Anodontia
• Other Study ID Numbers: SOD/ERB/2025/77

Drug and device information, study documents

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