Bone lid technique versus standard curettage for maxillofacial cysts: a prospective 3D CBCT study of bone...

Preservation of cortical bone during surgical management of maxillofacial cysts may enhance early bone regeneration and functional recovery. This study aimed to compare the clinical and radiographic outcomes of the Bone Lid Technique versus standard curettage.

In this single-center randomized controlled trial, 60 patients with maxillofacial cysts ≥ 3 × 3 × 3 mm were assigned to the Bone Lid group [Formula: see text] or standard curettage group [Formula: see text]. CBCT-based three-dimensional analyses assessed defect volume, surface area, and grayscale value. Periodontal outcomes (probing depth [PD], clinical attachment level [CAL]) and tooth mobility were evaluated at baseline, 3, 6, and 9 months. Percentage changes between consecutive visits were analyzed using linear mixed-effects models, while longitudinal tooth mobility was analyzed using ordinal logistic mixed-effects models. Baseline lesion size was additionally evaluated as a potential confounding factor. A lesion-size sensitivity analysis was performed after excluding lesions in the lowest quartile of the pooled baseline defect-volume distribution. Binary logistic regression was additionally used to assess tooth stability at 9 months.

Compared with the standard curettage group, the Bone Lid group showed significantly greater reductions in defect surface area (β = 13.782, 95% CI 5.924-21.640, P = 0.001) and volume (β = 22.436, 95% CI 14.285-30.587, P < 0.001), and greater increase in grayscale values (β = - 4.615, 95% CI - 8.292 to - 0.938, P = 0.014). PD and CAL improved more favorably in the Bone Lid group (β = 22.548 and 53.913, both P < 0.001). Tooth mobility decreased progressively in both groups, but recovery was faster and more stable in the Bone Lid group. Binary logistic regression confirmed a higher probability of achieving stable teeth at 9 months in the Bone Lid group (OR = 4.42, 95% CI 1.15-17.03, P = 0.031).

The Bone Lid Technique was associated with more favorable early bone regeneration and enhanced tooth stability compared with standard curettage. However, the robustness of the surface-area finding should be interpreted cautiously because baseline lesion morphology differed between groups and the corresponding sensitivity estimate was less stable. It may be particularly beneficial for moderate-sized cystic defects, lesions involving multiple adjacent teeth, or cases where preservation of cortical bone and early functional recovery are priorities.

This clinical trial was registered at chictr.org.cn on June 16, 2025 and had registration number ChiCTR2500104364.Retrospectively registered.