Endodontically Treated Teeth, Indirect Restoration
Conditions
Keywords
Indirect restoration, CAD-CAM dentistry, 3D printing dentistry, Hybrid resin restoration, Overlay restoration, Digital dentistry, VarseoSmile TriniQ, cerasmart
Brief summary
This randomized clinical trial aims to evaluate the clinical performance of a 3D-printed hybrid resin (VarseoSmile TriniQ) used for indirect restorations in endodontically treated teeth, compared with a CAD/CAM composite block (Cerasmart). In addition, two different luting protocols will be compared: a preheated microhybrid composite (Enamel Plus HRi) and a resin cement (RelyX Universal). Sixty patients requiring restoration of an endodontically treated molar with an indirect adhesive overlay will be recruited at the University Dental Clinic of the Universitat Internacional de Catalunya (Barcelona, Spain). Participants will be randomly assigned to receive restorations fabricated either using the printed hybrid resin or the CAD/CAM composite material. Each material group will be further divided according to the cementation technique used. All restorations will be fabricated following a digital workflow that includes intraoral scanning, CAD design, and either additive manufacturing (3D printing) or subtractive milling. Adhesive luting procedures will be performed according to standardized clinical protocols. Clinical evaluations will be performed at baseline, 3 months, 6 months, and 12 months, and annually thereafter. The clinical performance of the restorations will be assessed using modified United States Public Health Service (USPHS) criteria, including parameters such as marginal adaptation, contact points, color stability, wear, fracture occurrence, secondary caries, and patient comfort. The results of this study will provide clinical evidence regarding the behavior of 3D-printed hybrid resin restorations and their potential use as an alternative to conventional CAD/CAM composite materials for indirect restorations in endodontically treated teeth.
Detailed description
Digital dentistry has significantly evolved over recent decades with the development of computer-aided design and computer-aided manufacturing (CAD/CAM) technologies. These digital workflows allow the design and fabrication of indirect restorations with high precision and efficiency. Traditionally, most CAD/CAM restorations have been produced using subtractive manufacturing techniques such as milling. However, additive manufacturing through three-dimensional printing is increasingly being introduced in dentistry and may offer advantages such as reduced material waste, lower manufacturing costs, and the ability to fabricate complex geometries. Recently, a hybrid ceramic-filled resin specifically designed for additive manufacturing of definitive restorations has been introduced (VarseoSmile TriniQ, BEGO, Bremen, Germany). This material consists of a resin matrix filled with ceramic particles and is indicated for permanent restorations including crowns, inlays, onlays, and veneers. Although promising, clinical evidence regarding the performance of this printed hybrid material is still limited. Composite CAD/CAM blocks such as Cerasmart (GC, Tokyo, Japan) are widely used for indirect restorations due to their favorable mechanical properties, wear resistance, and reparability. These materials combine characteristics of ceramics and composites and have demonstrated good clinical performance in previous studies. However, it remains unclear whether the newer printed hybrid materials provide comparable clinical outcomes. Another important factor influencing the longevity of indirect restorations is the luting procedure. Preheated restorative composite resins have been proposed as an alternative to traditional resin cements for adhesive luting of indirect restorations. This technique may improve mechanical properties and reduce marginal gaps, but clinical evidence comparing these approaches remains limited. The aim of this randomized clinical trial is therefore to evaluate the clinical behavior of indirect overlay restorations fabricated with a 3D-printed hybrid resin (VarseoSmile TriniQ) compared with restorations fabricated from a CAD/CAM composite block (Cerasmart). Additionally, two cementation strategies will be evaluated: a preheated microhybrid composite resin (Enamel Plus HRi) and a resin cement (RelyX Universal). A total of 60 patients requiring restoration of an endodontically treated molar with an indirect overlay will be recruited at the University Dental Clinic of the Universitat Internacional de Catalunya (Barcelona, Spain). Participants will be randomly allocated into four groups according to the restorative material and cementation protocol used. All teeth will receive standardized preparation procedures for adhesive indirect overlays, including immediate dentin sealing when indicated. Restorations will be designed using CAD software and fabricated either by additive manufacturing (3D printing) or subtractive milling. Adhesive luting will be performed following standardized protocols using rubber dam isolation. Clinical evaluations will be performed at baseline, 3 months, 6 months, and 12 months, and annually thereafter. Outcomes will be assessed using modified United States Public Health Service (USPHS) criteria. The evaluated parameters will include marginal adaptation, contact points, color stability, polishability, wear, fracture occurrence, secondary caries, and patient comfort. The results of this study are expected to provide new clinical evidence regarding the performance of 3D-printed hybrid resin restorations and the influence of different luting protocols in indirect restorations of endodontically treated teeth.
Interventions
PROCEDUREIndirect adhesive overlay restoration
Indirect overlay restoration performed on endodontically treated molars following a standardized digital workflow including tooth preparation, intraoral scanning, CAD design, and fabrication using either a 3D-printed hybrid resin (VarseoSmile TriniQ) or a CAD/CAM composite block (Cerasmart). Adhesive cementation is performed under rubber dam isolation.
DEVICEEnamel Plus HRi
Preheated microhybrid composite resin used as a luting material for indirect restorations. The composite is preheated to improve flowability and used as an adhesive luting agent following a standardized clinical protocol.
DEVICERelyX Universal
Resin cement used for adhesive luting of indirect restorations according to the manufacturer's instructions and standardized clinical protocol.
DEVICEVarseoSmile TriniQ (3D-printed hybrid resin)
Definitive indirect overlay fabricated using the 3D-printed hybrid resin VarseoSmile TriniQ (BEGO) following manufacturer-recommended printing and post-curing procedures.
DEVICECerasmart (CAD/CAM composite block)
Definitive indirect overlay fabricated from the CAD/CAM resin-composite block Cerasmart (GC) using a standardized milling and finishing protocol.
Sponsors
Universitat Internacional de Catalunya
Study design
Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
The clinical evaluator responsible for assessing the outcomes will be blinded to the restorative material and luting protocol used. Due to the nature of the interventions, operators performing the procedures cannot be blinded.
Intervention model description
This study follows a 2×2 factorial randomized design. Participants requiring restoration of an endodontically treated molar with an indirect overlay will be randomly allocated to receive restorations fabricated using one of two restorative materials (3D-printed hybrid resin VarseoSmile TriniQ or CAD/CAM composite Cerasmart). Each material group will be further randomized according to the luting protocol used (preheated microhybrid composite Enamel Plus HRi or resin cement RelyX Universal), resulting in four study groups.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥18 years * Signed informed consent * Need to restore an endodontically treated molar with an indirect adhesive overlay * Physically and psychologically able to tolerate conventional restorative procedures * No high caries risk * No active periodontal disease * Natural antagonist tooth present * Need for full cuspal coverage restoration (overlay) * Remaining wall thickness \<3 mm in the endodontically treated tooth * Occlusal thickness of the restoration ≥1 mm * Willing and able to attend follow-up visits
Exclusion criteria
* Poor oral hygiene * Uncontrolled parafunctional habits (e.g., bruxism) * High caries risk * Active periodontal disease * Active pulpal disease * Absence of natural antagonist tooth * Need for partial cuspal coverage restoration (inlay or onlay) * Insufficient interarch space for restoration * Teeth planned as abutments for removable or fixed prostheses * Known allergy to any materials used in the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Clinical success of indirect overlay restorations | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Clinical success of indirect overlay restorations placed on endodontically treated molars assessed using the modified United States Public Health Service (USPHS) criteria. Each restoration will be evaluated for marginal adaptation, contact points, color stability, wear, fracture, and secondary caries. USPHS scores are classified as Alpha (ideal clinical condition), Bravo (clinically acceptable), or Charlie (clinically unacceptable requiring replacement). Comparisons will be performed between restorative materials (3D-printed hybrid resin VarseoSmile TriniQ and CAD/CAM composite Cerasmart) and between luting protocols (preheated microhybrid composite Enamel Plus HRi and resin cement RelyX Universal). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Marginal adaptation of the restoration | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Assessment of marginal adaptation of the indirect restoration using modified USPHS criteria during follow-up examinations. Scores will be classified according to modified USPHS criteria (Alpha = ideal, Bravo = clinically acceptable, Charlie = clinically unacceptable). |
| Proximal contact stability | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Evaluation of proximal contact points between the restoration and adjacent teeth during follow-up visits. Scores will be classified according to modified USPHS criteria (Alpha = ideal, Bravo = clinically acceptable, Charlie = clinically unacceptable). |
| Color stability of the restoration | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Clinical assessment of color match and color stability of the restoration during follow-up using modified USPHS criteria. Scores will be classified according to modified USPHS criteria (Alpha = ideal, Bravo = clinically acceptable, Charlie = clinically unacceptable). |
| Wear of the restoration | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Evaluation of occlusal wear of the restoration during clinical follow-up using modified USPHS criteria. Scores will be classified according to modified USPHS criteria (Alpha = ideal, Bravo = clinically acceptable, Charlie = clinically unacceptable). |
| Restoration fracture or chipping | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Assessment of the presence of fractures or chipping of the indirect restoration during follow-up examinations. Scores will be classified according to modified USPHS criteria (Alpha = ideal, Bravo = clinically acceptable, Charlie = clinically unacceptable). |
| Secondary caries adjacent to the restoration | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Detection of caries adjacent to restoration margins during clinical follow-up visits. Scores will be classified according to modified USPHS criteria (Alpha = ideal, Bravo = clinically acceptable, Charlie = clinically unacceptable). |
| Patient-reported comfort with the restoration | Baseline, 3 months, 6 months, and 12 months after restoration placement. | Assessment of patient-reported comfort and satisfaction with the indirect restoration during follow-up visits. Scores will be classified according to modified USPHS criteria (Alpha = ideal, Bravo = clinically acceptable, Charlie = clinically unacceptable). |
| Restoration survival | From restoration placement to 12 months after placement. | Survival of the indirect overlay restoration during follow-up. A restoration will be considered a failure if it requires replacement due to fracture, debonding, secondary caries, unacceptable marginal adaptation, or any other clinical complication preventing proper function. |
Countries
Spain
Contacts
CONTACTMARTA VALLES, DDS, PhD
CONTACTPatricia Freire, DDS
PRINCIPAL_INVESTIGATORMARTA VALLES
Universitat Internacional de Catalunya
Outcome results
None listed