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Repair Versus Replacement of Failed Restorations in Primary Teeth

Repair Versus Replacement of Failed Restorations in Primary Teeth: Protocol for a Non-Inferiority Randomized Clinical Trial

Status
Not yet recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07813065
Enrollment
382
Registered
2026-09-10
Start date
2026-10-07
Completion date
2029-04-01
Last updated
2026-09-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Dental Caries, Primary Teeth, Restoration Defects

Keywords

Tooth, Deciduous, Dental Restoration Failure, Dental Restoration, Permanent, Glass Ionomer Cements;, Child, Randomized Controlled Trial;

Brief summary

Dental caries affect approximately 573 million children globally, and the management of failed restorations is a frequent clinical issue in pediatric dentistry. Although complete replacement of restorations is traditionally the most commonly adopted approach, repair represents a minimally invasive alternative that preserves healthy dental structure and reduces the risk of pulpal complications. Studies in permanent teeth demonstrate that repair may present longevity similar to replacement; however, there is no robust evidence regarding this comparison in primary teeth. This randomized controlled clinical trial, with parallel groups and a 1:1 allocation ratio, aims to evaluate the non-inferiority of repair compared with replacement of failed restorations in primary molars, using encapsulated high-viscosity glass ionomer cement. Children aged 4 to 8 years with at least one failed restoration eligible for repair in primary molars will be included. Randomization will be stratified by number of surfaces. Teeth (n=824) will be randomly allocated to one of the groups: repair or replacement. The primary outcome will be restoration survival at 24 months. Cost-effectiveness will be evaluated as a secondary outcome. Statistical analysis will use Kaplan-Meier curves and Cox regression with shared frailty (¿=5%).

Interventions

PROCEDURERepair of Failed Restoration

Prior to the procedure, when needed, local anesthesia with 2% lidocaine and 1:100,000 epinephrine will be used, with relative isolation (cotton rolls and saliva ejector). The defective area will be clinically identified. When present, carious tissue will be selectively removed with hand instruments (dentin curettes) suited to the cavity, preserving as much of the intact original restoration as possible. If no hand instrument fits, the cavity will be enlarged with a small spherical diamond bur at high speed under cooling. The surface will be conditioned with 20% polyacrylic acid (GC Cavity Conditioner) for 10 s, rinsed abundantly, and dried with cotton pellets. For proximal surfaces, a metal matrix and wedge will be placed before the GIC. The capsule will be activated, mixed for 10 s, inserted with an applicator, and adapted by digital pressure with petroleum jelly. Occlusion will be checked with articulating paper and adjusted; surface protection applied with petroleum jelly.

PROCEDUREReplacement of Failed Restoration

Prior to the procedure, when needed, infiltrative local anesthesia with 2% lidocaine and 1:100,000 epinephrine will be administered. Relative isolation will be used, with cotton rolls and a saliva ejector. Complete removal of the defective restorative material will be performed with spherical diamond burs at high speed under cooling, complemented by round burs at low speed to remove remaining restorative material. Selective removal of carious tissue, when present, will be carried out with hand instruments (dentin curettes) suited to the cavity, preserving soft or leathery dentin according to the depth of the lesion. The new restoration will then be placed following the same protocol described for the repair group: conditioning with 20% polyacrylic acid (GC Cavity Conditioner) for 10 s, rinsing and removal of excess water; placement of a metal matrix and wedge, when needed; insertion of the GIC into the cavity; adaptation by digital pressure with petroleum jelly; occlusal adjustment; a

Sponsors

University of Sao Paulo
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
4 Years to 8 Years
Healthy volunteers
No

Inclusion criteria

* Children aged 4 to 8 years; * Presence of at least one defective restoration in a primary molar, involving no more than 3 surfaces; * Absence of clinical and radiographic signs of pulp involvement;

Exclusion criteria

* Tooth without pulp vitality or requiring endodontic treatment; * Loose or mobile restoration; * Presence of fistula, abscess, or history of pain; * Tooth mobility incompatible with the physiological exfoliation timeline; * Parents/guardians who do not consent to participation by signing the ICF, or children who do not assent to participate in the study.

Design outcomes

Primary

MeasureTime frameDescription
Restoration survival24 monthsRestoration survival will be assessed based on clinical evaluation of the restorations at 6, 12, 18, and 24 months. A restoration will be considered to have survived when it remains clinically satisfactory according to the following criteria. Single-surface restorations will be considered satisfactory when scored as 0 (restoration present and satisfactory), 1 (restoration present, with a slight marginal defect and/or surface wear of less than 0.5 mm in depth, with no need for repair), or 7 (restoration present, with gradual wear involving larger areas of the restoration but less than 0.5 mm in depth at the deepest point, with no need for repair), according to Frencken et al. (1996). Multiple-surface restorations will be considered satisfactory when scored as 00 (restoration present and satisfactory) or 10 (restoration present, with a slight marginal defect and/or surface wear of less than 0.5 mm in depth, with no need for repair), according to Rôlevald et al. (2006).

Secondary

MeasureTime frameDescription
Treatment success24 monthsTreatment success at 24 months will be assessed as a binary outcome. All participants will be clinically evaluated at 24 months, and each treated tooth will be classified as either successful or unsuccessful. Treatment will be considered successful when the treated tooth requires no operative reintervention during the 24-month follow-up period and remains asymptomatic, according to the clinical criteria described above. Natural exfoliation of the treated tooth during the follow-up period will also be considered a successful outcome. Treatment failure will be defined as the need for operative reintervention due to disease progression or treatment failure, including endodontic treatment or extraction.
Parents' and Child's PreferenceBefore randomization and prior to treatmentBefore randomization, parents or guardians and the child will receive a standardized explanation of the two therapeutic approaches under investigation (replacement and repair of restorations). To aid comprehension, illustrative images generated by artificial intelligence will be presented, depicting each procedure in a standardized manner. Parents or guardians and the child will then be asked: "If you could choose, which treatment would you prefer?" Responses will be recorded as: replacement, repair, or no preference.
Treatment TimeFrom the beginning to the completion of the treatment procedureThe total treatment time will be measured by a research assistant using a digital stopwatch. Timing will start at the beginning of the clinical intervention and stop immediately after its completion. Time will be recorded and expressed in minutes (min).
Child's PerceptionImmediately after the procedure (Day 0)The child's perception of the treatment will be assessed immediately after completion of the procedure using the Facial Image Scale (FIS). The scale will be presented by the research assistant, in the absence of the operator, in order to minimize the professional's influence on the response. The child will be asked to indicate the image that best represents how they felt during the treatment, following the question: "How did you feel during the treatment?" The FIS consists of five facial images ranging from a very happy to a very sad expression, allowing assessment of the child's acceptance of the experience.
Parents'/Guardians' SatisfactionImmediately after the procedure (Day 0)Immediately after completion of the treatment, parents or guardians will answer the following question: "How satisfied are you with the treatment performed on your child?" The response will be recorded on a five-point Likert scale, ranging from very dissatisfied to very satisfied.
Parents'/Guardians' Willingness to Choose the Treatment Again30 days after the procedureAt 30 days after the procedure, parents or guardians will be presented again with illustrative images of the two therapeutic approaches, accompanied by the same standardized explanation used in the initial assessment. They will then be asked: "If you could choose again, which treatment would you choose for your child?" Responses will be recorded as repair, replacement, or no preference.
Cost-effectiveness24 monthsAdditionally, a cost-effectiveness analysis will be conducted comparing the repair and replacement of defective restorations in primary molars over 24 months of follow-up. Restoration survival over this period will be used as the effectiveness measure for the economic analysis. The analysis will adopt the perspective of the Brazilian public health system and will consider only direct treatment costs.
Treatment CostImmediately after the procedure (Day 0)The direct costs associated with the repair and replacement of restorations will be compared, considering the clinical treatment time and materials actually used in each procedure. Treatment time will be measured by a research assistant who is not involved in performing the interventions and will be used to estimate the dental professional's labor cost based on the cost per hour of professional work. Material costs will be estimated based on the actual amount consumed during each procedure and the prices obtained from three quotations from different suppliers, with the mean value of the quotations used for cost calculation. Costs will be expressed in Brazilian reais (BRL), based on the prices prevailing during the study period.

Countries

Brazil

Contacts

CONTACTTamara K Tedesco, PhD
tamarakt@usp.br+5511954866622
PRINCIPAL_INVESTIGATORCamila C Cabral, PhD

University of Sao Paulo

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Sep 11, 2026