Comparison of Clinical Performance of Preformed CAD/CAM Milled PMMA Crown and Stainless Steel Crown for Primary Molar Teeth Using Dental Operating Microscope.

Abstract

Background: Full-coverage restorations are essential for the long-term preservation of extensively carious primary molars. While preformed stainless steel crowns (P-SSCs) are the gold standard due to their durability, esthetic concerns have led to the development of alternative options such as preformed 3D-milled polymethylmethacrylate (P-PMMA) crowns, which offer improved appearance and marginal adaptation.

Aim: To compare the clinical efficiency of P-PMMA crowns and P-SSCs in restoring mandibular second primary molars over a 6-month period in terms of gingival health, occlusal wear, and crown failure/dislodgement.

Materials and methods: A randomized controlled clinical trial was conducted on 34 children aged 4-8 years with bilateral carious mandibular second primary molars. Using a split-mouth design, one molar received a P-SSC and the contralateral molar received a P-PMMA crown. Clinical evaluations were performed at baseline, 3 months, and 6 months. Parameters assessed included gingival health (using modified gingival index), occlusal wear (visual-tactile assessment), and crown retention. Data were analyzed using paired t-tests and Chi-square tests (p < 0.05 considered significant).

Results: Both crown types demonstrated satisfactory performance at 6 months. P-SSCs showed slightly higher retention rates, while P-PMMA crowns had better esthetic outcomes and comparable gingival health. No statistically significant differences were observed in occlusal wear between the groups.

Conclusion: Preformed polymethylmethacrylate crowns are a clinically acceptable esthetic alternative to P-SSCs for mandibular second primary molars, showing comparable short-term performance with enhanced patient and parent satisfaction.

How to cite this article: Shanmugaavel AK, Balakrishnan P, Nandhini T, et al. Comparison of Clinical Performance of Preformed CAD/CAM Milled PMMA Crown and Stainless Steel Crown for Primary Molar Teeth Using Dental Operating Microscope. Int J Clin Pediatr Dent 2026;19(2):139-144.