Resin Infiltration with Flowable Resin Composite Sealing for Non-Cavitated Occlusal Caries: A Retrospective Cohort Study

Summary

This retrospective cohort study compares resin infiltration combined with flowable resin composite pit-and-fissure sealing versus sealing alone for non-cavitated initial occlusal carious lesions in permanent molars.

Abstract

Non-cavitated occlusal pit-and-fissure carious lesions in permanent molars are common among children and adolescents; however, evidence remains limited on whether resin infiltration, combined with flowable resin composite pit-and-fissure sealing, provides superior short-term lesion control compared with sealing alone. This single-center retrospective cohort study included permanent molars with non-cavitated occlusal pit-and-fissure carious lesions, classified according to the International Caries Detection and Assessment System (ICDAS) codes 1–2, in patients aged 6–18 years. The affected tooth served as the unit of analysis. The primary outcome was lesion progression within 12 months, defined as cavitation or localized enamel breakdown, a new radiolucency in dentin, or an operative restoration due to caries progression on the same occlusal surface. A total of 842 patients with 1,117 affected teeth were included, of which 989 teeth had evaluable 12-month outcomes, comprising 330 teeth in the combined-treatment group and 659 teeth in the sealing-alone group. Lesion progression occurred in 6.97% of teeth treated with the combined approach compared with 13.05% of teeth treated with sealing alone, corresponding to an absolute risk reduction of 6.08 percentage points. Modified Poisson regression with generalized estimating equations demonstrated that the combined treatment was associated with a significantly lower 12-month risk of lesion progression after adjustment for prespecified confounders (adjusted RR, 0.52; 95% CI, 0.33–0.82; p = 0.005). Sensitivity analyses, including complete-case analysis, inverse probability of treatment weighting, restriction to baseline ICDAS 2 lesions, and exclusion of partially erupted molars, yielded consistent findings (RRs, 0.51, 0.54, 0.49, and 0.56; p = 0.006, 0.008, 0.009, and 0.022, respectively). These findings suggest that resin infiltration combined with flowable resin composite pit-and-fissure sealing may provide more effective short-term control of lesion progression than sealing alone and may represent a useful microinvasive treatment option for non-cavitated initial occlusal pit-and-fissure carious lesions in permanent molars.

Introduction

Dental caries remains one of the oral diseases with the heaviest global burden. The World Health Organization has reported that oral diseases affect nearly 3.7 billion people worldwide, and untreated caries in permanent teeth is among the most common health conditions in the Global Burden of Disease Study¹. The pit-and-fissure surfaces of permanent molars in children and adolescents are particularly susceptible to caries because of their deep, narrow morphology and the difficulty of effective plaque control in these areas. Modern caries management has shifted from post-cavitation restorations to early lesion control and tooth preservation based....

Protocol

This single-center retrospective cohort study was designed and reported in accordance with the STROBE Statement¹⁴. The study used previously acquired outpatient medical records, intraoral photographs, and digital imaging data without requiring any additional examinations or treatments. The study protocol was approved by the Ethics Committee of Sinopharm Dongfeng Stomatological Hospital, Hubei University of Medicine (approval number LW-2026-01). Because all data had been de-identified before analysis, the ethics committee waived the requirement for informed consent.

Case source and study population

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Results

Study population screening and baseline characteristics

During the study period, 1,278 patients were screened, and 1,694 candidate affected-tooth records were identified. After exclusion of 577 teeth, 1,117 affected teeth from 842 patients were included in the baseline cohort. A total of 989 affected teeth had an evaluable primary outcome at 12 months: 330 teeth in the combined treatment group (292 patients) and 659 teeth in the sealing-alone group (593 patients).

Discussion

Resin infiltration combined with flowable resin composite pit-and-fissure sealing was associated with a significantly lower 12-month risk of lesion progression than sealing alone. The adjusted relative risk was 0.52, with the 95% confidence interval excluding 1.00 and a corresponding p value of 0.005; therefore, the prespecified null hypothesis of no difference between the two treatment groups was rejected. Because treatment was not randomly allocated, these findings should be interpreted as an adjusted associat.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
37% phosphoric acid etchant (Total Etch)	Ivoclar Vivadent AG, Schaan, Liechtenstein	550588AN	37% phosphoric acid etching gel used for enamel etching before pit-and-fissure sealing.
Ball-ended probe / WHO probe (Qulix CP-11.5B Probe)	HuFriedyGroup, Chicago, IL, USA	PCP11.5B6	Single-ended, color-coded WHO CP-11.5B ball-ended probe used to remove debris and confirm surface continuity without sharp probing.
Digital bitewing imaging system (RVG 6200 Intraoral Sensor, Size 2)	Carestream Dental LLC, Atlanta, GA, USA	1065804	Size 2 CMOS intraoral digital X-ray sensor used for posterior bitewing radiography.
Flowable resin composite (Filtek Supreme Flowable Restorative, shade A2)	3M Oral Care / Solventum, St. Paul, MN, USA	6032A2	Light-curing flowable resin composite used for pit-and-fissure sealing after adhesive application.
Fluoride-free prophylaxis paste (Cleanic in Tube without Fluoride, Mint, 100 g)	Kerr Corporation / Envista, Orange, CA, USA	3183	Fluoride-free prophylaxis paste used for tooth-surface cleaning before examination and treatment.
Intraoral photography system (EyeSpecial C-V Dental Camera)	SHOFU Dental GmbH, Ratingen, Germany	E0027	Dental camera system used for standardized intraoral photography and retrospective outcome review.
LED light-curing unit (Woodpecker iLED Plus)	Guilin Woodpecker Medical Instrument Co., Ltd., Guilin, Guangxi, China	iLED Plus	Dental LED curing light with an output intensity of 1,000–2,500 mW/cm².
R statistical software and packages	R Foundation for Statistical Computing, Vienna, Austria; Comprehensive R Archive Network	R 4.4.2; geepack 1.3.12; mice 3.17.0; WeightIt 1.4.0; cobalt 4.5.5; tableone 0.13.2	Used for modified Poisson generalized estimating equations, cluster-robust variance estimation, multiple imputation, propensity-score inverse probability of treatment weighting, covariate-balance diagnostics, standardized mean differences, and baseline table generation.
Resin infiltration system (Icon; Icon Etch, Icon Dry, and Icon Infiltrant)	DMG Chemisch-Pharmazeutische Fabrik GmbH, Hamburg, Germany	Kit catalog number: 220403 (confirm against product packaging)	System comprising 15% hydrochloric acid etching gel, 99% ethanol drying agent, and low-viscosity light-curing resin infiltrant used for enamel lesion infiltration.
Rubber dam system (Hygenic Dental Dam Starter Kit with Winged Clamps)	COLTENE / Hygenic, Cuyahoga Falls, OH, USA	H02778	Dental dam isolation kit used when tooth position and eruption status permitted stable clamp placement and complete field control.
Universal adhesive (Scotchbond Universal Adhesive)	3M Oral Care / Solventum, St. Paul, MN, USA	41258	Light-curing universal dental adhesive used before placement of the flowable resin composite.