Zinc Oxide in Kids' Teeth: Does it Really Help?

randomized-controlled-trial PMID: 36719000

Quick Summary: Researchers compared two dental treatments for kids' baby teeth with infected pulp (the soft tissue inside the tooth). Both treatments, one using a paste with zinc oxide, worked about the same after three years.

What The Research Found

This study looked at how well different treatments worked for infected baby teeth. Both treatments used zinc oxide, but one also had antibiotics. After three years, both treatments were equally good at making the teeth healthy. However, neither treatment was great at completely healing the teeth on X-rays.

Study Details

Who was studied: 70 children, aged 3-8 years old, with infected baby molars (back teeth).

How long: The study followed the children for 3 years (36 months).

What they took:

Group 1: A paste containing antibiotics (chloramphenicol and tetracycline), zinc oxide, and eugenol.
Group 2: A paste containing only zinc oxide and eugenol.

What This Means For You

If your child needs a baby tooth treated for an infection, this study suggests that both treatment options are likely to be effective in the short term. Your dentist will consider factors like the severity of the infection and your child's overall health when deciding on the best treatment. Zinc oxide is a common ingredient in these types of dental treatments.

Study Limitations

The study only looked at the teeth for three years. We don't know how the treatments would work long-term.

The study didn't isolate the effects of zinc oxide. Both treatments used it, so we can't say for sure how much zinc oxide helped.

The study involved a limited number of children, so the results might not apply to everyone.

X-ray results weren't great for either treatment.

Key Findings

This 36-month randomized controlled trial found no statistically significant differences between lesion sterilization and tissue repair (LSTR) using chloramphenicol/tetracycline/zinc oxide/eugenol (CTZ) paste and conventional pulpectomy with zinc oxide/eugenol (ZOE) paste in treating primary molars with pulp necrosis. Clinical success rates were 86.4% (CTZ) and 90.9% (ZOE) (p=0.45), while radiographic success was identical at 43.2% (p=1.00). Overall success rates were 40.9% (CTZ) and 43.2% (ZOE) (p=1.00). Both approaches demonstrated comparable effectiveness, though radiographic outcomes were suboptimal.

Study Design

A parallel-group RCT enrolled 88 primary molars from 70 children (3–8 years old) with pulp necrosis. Participants were randomized to either LSTR with CTZ paste or conventional pulpectomy with ZOE paste. Clinical and radiographic evaluations occurred at 18, 24, 30, and 36 months post-treatment. The study duration spanned 3 years, with a focus on longitudinal outcomes in pediatric dentistry.

Dosage & Administration

The CTZ paste contained chloramphenicol, tetracycline, zinc oxide, and eugenol, while the ZOE paste included zinc oxide and eugenol only. Exact concentrations of zinc oxide in each paste were not specified in the summary. The LSTR technique involved lesion sterilization and tissue repair, whereas pulpectomy followed conventional root canal procedures. Both pastes were applied locally within the root canal system during treatment.

Results & Efficacy

At 36 months:
- Clinical success: CTZ (86.4%) vs. ZOE (90.9%) (p=0.45, not significant).
- Radiographic success: Both groups showed 43.2% success (p=1.00).
- Overall success: CTZ (40.9%) vs. ZOE (43.2%) (p=1.00).
While CTZ and ZOE pastes achieved high clinical success rates (>85%), radiographic outcomes were poor in both groups. The lack of significant differences across all metrics suggests neither approach is superior for primary molars with pulp necrosis.

Limitations

Sample size: 88 teeth (70 children) may limit generalizability.
Radiographic interpretation: Subjective radiographic assessments could introduce bias.
Zinc-specific effects obscured: CTZ and ZOE pastes both contained zinc oxide, preventing isolation of its individual contribution.
Short follow-up relative to tooth lifespan: 36-month results may not reflect long-term outcomes post-exfoliation.
No placebo control: Both groups received active treatments, limiting conclusions about zinc oxide’s standalone efficacy.

Clinical Relevance

For pediatric dental practitioners, both CTZ and ZOE pastes appear similarly effective for managing pulp necrosis in primary molars over 3 years. However, the low radiographic success rates (43.2%) suggest neither approach fully resolves underlying pathology, warranting cautious interpretation. Zinc oxide’s role in both formulations aligns with its established use in pediatric endodontics, but further research is needed to optimize regenerative outcomes. Treatment decisions may hinge on cost, ease of application, or antimicrobial coverage rather than efficacy differences.

Source: PubMed (2023)