Endodontically Treated Teeth, Periodontal Health
Conditions
Keywords
Deep Margin Elevation, CAD/CAM, Endocrown, Periodontal Response, Split-Mouth Study, DME
Brief summary
This study aims to evaluate the periodontal response of proximal surfaces with deep margin elevation (DME) in endodontically treated posterior teeth restored with CAD/CAM systems. Deep subgingival margins present clinical challenges in terms of isolation, restoration, and long-term periodontal health. DME is a minimally invasive technique used to relocate subgingival margins coronally to a supragingival level, facilitating adhesive procedures and CAD/CAM restoration placement. However, the periodontal effects of DME remain unclear. In this prospective split-tooth clinical study, proximal surfaces treated with DME will be compared with control surfaces without DME within the same tooth. The primary outcome will be bleeding on probing (BOP), while secondary outcomes will include probing depth and plaque index. Clinical and radiographic evaluations will be performed at baseline and during follow-up. The results of this study are expected to provide clinical evidence regarding the periodontal impact of DME and support clinical decision-making in the restoration of endodontically treated posterior teeth.
Detailed description
This prospective split-tooth controlled clinical study aims to evaluate the periodontal response associated with deep margin elevation (DME) in endodontically treated posterior teeth restored with CAD/CAM systems. Endodontically treated teeth frequently present with extensive structural loss due to caries, previous restorations, or endodontic access cavity preparation, which compromises the structural integrity of the tooth. In such cases, deep subgingival margins are commonly encountered, making isolation, adhesive procedures, and restorative treatment more challenging. Deep margin elevation (DME) is a minimally invasive technique used to relocate subgingival margins coronally to the cemento-enamel junction level using resin composite, facilitating adhesive procedures, digital impression taking, and CAD/CAM restoration placement. However, the periodontal effects of DME remain unclear and require further clinical investigation. A total of 45 restorations will be included in patients aged between 18 and 65 years who present with at least one endodontically treated posterior tooth with extensive coronal destruction. A split-tooth design will be used, where one proximal surface requiring deep margin elevation will be assigned as the test surface (DME), while the opposing proximal surface with supragingival or equigingival margin will serve as the control. All clinical procedures will be performed at the Department of Restorative Dentistry, Faculty of Dentistry, Hacettepe University. Before treatment, professional cleaning will be performed using a pumice-water mixture and polishing instruments to remove plaque accumulation. All restorative procedures will be carried out under rubber dam isolation using ×3 magnification dental loupes. During the DME procedure, isolation will be achieved using a sectional matrix system and wedges. A universal adhesive system (G-Premio Bond, GC, Tokyo, Japan) will be applied following enamel conditioning with 37% phosphoric acid for 10-15 seconds. The subgingival margin will then be elevated to the enamel level using a high-filled injectable composite resin (G-ænial Universal Injectable, GC, Tokyo, Japan). All restorations will be fabricated using a chairside CAD/CAM system (CEREC Omnicam, Dentsply Sirona, Bensheim, Germany) and milled from a resin nanoceramic hybrid block (Cerasmart 270, GC, Tokyo, Japan) according to the manufacturer's instructions. The internal surface of the restoration will be sandblasted with 50 µm aluminum oxide, cleaned with alcohol, and treated with G-CEM ONE Adhesive Primer (GC, Tokyo, Japan). The tooth surface will be conditioned with 37% phosphoric acid, followed by the application of G-Premio Bond. Restorations will be luted using a self-adhesive resin cement (G-CEM ONE, GC, Tokyo, Japan). Excess cement will be removed after short light exposure, and final polymerization will be performed using a high-intensity LED curing unit (Bluephase N, Ivoclar Vivadent), with 10 seconds of curing per surface. Finishing and polishing procedures will be completed using fine diamond burs, aluminum oxide-coated polishing discs, and polishing systems. Occlusion will be checked and adjusted when necessary. Periodontal parameters will be recorded at baseline (T0) and at follow-up visits at 1 week, 6 months, and 12 months. The primary outcome measure will be bleeding on probing (BOP), assessed at six sites per tooth, and the presence of bleeding at any site will be recorded as positive. Secondary outcome measures will include probing pocket depth (PPD) measured in millimeters and plaque index (PI). Gingival index (GI) will also be recorded as an additional parameter. Restorations will be evaluated according to FDI criteria by two calibrated clinicians who are blinded to the intervention. Functional, biological, esthetic, and patient-related parameters will be assessed. Patient satisfaction will be evaluated using a 5-point Likert scale including general, esthetic, and functional satisfaction. Sample size calculation was performed using G\*Power 3.1 software based on McNemar test assumptions for paired data (α=0.05, power=80%). Based on estimated discordant proportions (p10=0.27 and p01=0.03), the minimum required sample size was calculated as 40 teeth. Considering a potential 10% dropout rate, a total of 45 restorations will be included. Statistical analysis will be performed using SPSS software. Differences in BOP between test and control surfaces will be analyzed using the McNemar test. PPD and PI values will be analyzed using the Wilcoxon signed-rank test. Changes over time will also be evaluated using paired statistical methods. A significance level of p\<0.05 will be considered statistically significant. This study is expected to provide clinically relevant evidence regarding the periodontal effects of deep margin elevation and contribute to evidence-based decision-making in the restorative management of endodontically treated posterior teeth.
Interventions
PROCEDUREDeep Margin Elevation
Deep margin elevation (DME) is performed by relocating subgingival proximal margins coronally using a high-filled injectable composite resin following adhesive procedures, prior to CAD/CAM restoration placement.
PROCEDURECAD/CAM Restoration Without DME
Restorative treatment is performed without deep margin elevation, where proximal margins remain at supragingival or equigingival levels and are restored using CAD/CAM systems.
Sponsors
Hacettepe University
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
This study uses a split-tooth design, where different proximal surfaces of the same tooth receive different interventions. One proximal surface is treated with deep margin elevation (DME), while the opposing surface serves as the control without DME. This design allows direct intra-tooth comparison of periodontal outcomes under identical patient-related conditions.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Patients aged between 18 and 65 years * Presence of at least one endodontically treated posterior tooth (premolar or molar) with extensive coronal structure loss * Teeth indicated for indirect CAD/CAM restoration * Presence of at least one proximal surface requiring deep margin elevation (subgingival margin) * Opposing proximal surface with supragingival or equigingival margin suitable as control * Good general health and ability to attend follow-up visits * Signed informed consent
Exclusion criteria
* Patients with poor oral hygiene or uncontrolled periodontal disease * Presence of active periodontal disease requiring treatment * Teeth with mobility greater than Grade I * Teeth with periapical pathology or unsuccessful endodontic treatment * Patients with systemic diseases affecting periodontal health (e.g., uncontrolled diabetes) * Pregnant or lactating women * Patients using medications affecting gingival tissues (e.g., immunosuppressants, calcium channel blockers) * Heavy smokers * Patients unable to comply with follow-up schedule
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Bleeding on Probing (BOP) Positive Surface Proportion | Baseline (1 week post-treatment), 6 months, and 12 months | Gingival inflammation will be assessed by measuring Bleeding on Probing (BOP) using a periodontal probe at six sites per tooth (mesio-buccal, mesio-lingual, mid-buccal, mid-lingual, disto-buccal, and disto-lingual) . The presence of bleeding at any site within the proximal area will be recorded as positive . The proportion of BOP-positive surfaces will be compared between the deep margin elevation (DME) surfaces (experimental group) and the non-DME supragingival surfaces (control group) on the same tooth. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in Periodontal Pocket Depth (PPD) | Baseline (1 week post-treatment), 6 months, and 12 months | Periodontal pocket depth (PPD) will be measured in millimeters using a periodontal probe at the same six sites per tooth (mesio-buccal, mesio-lingual, mid-buccal, mid-lingual, disto-buccal, and disto-lingual) . The distance from the gingival margin to the bottom of the periodontal pocket will be recorded to evaluate dimensional changes over time and compare DME vs. control surfaces. |
| Plaque Index (PI) Scores | Baseline (1 week post-treatment), 6 months, and 12 months | Gingival plaque accumulation will be evaluated at the evaluated proximal surfaces using the Silness and Löe Plaque Index scoring system.This ordinal index scores plaque retention specifically at the marginal area to assess oral hygiene correlation with the restorations. Plaque Index (PI) Scores: Plaque Index is assessed using the Silness and Löe Plaque Index, with scores ranging from 0 to 3, where 0 = no plaque, 1 = a film of plaque adhering to the free gingival margin and adjacent tooth surface, 2 = moderate accumulation of plaque, and 3 = abundant plaque accumulation. Higher scores indicate worse oral hygiene. |
| Gingival Index (GI) Scores | Baseline (1 week post-treatment), 6 months, and 12 months | Clinical evaluation of gingival health will be performed using the Löe and Silness Gingival Index\[cite: 1\]. The assessment will be conducted at both the deep margin elevation (DME) surface and the non-DME proximal surface using a periodontal probe to grade tissue condition and inflammation severity. Gingival Index (GI) Scores: Gingival health is assessed using the Löe and Silness Gingival Index, with scores ranging from 0 to 3, where 0 = normal gingiva, 1 = mild inflammation, 2 = moderate inflammation with bleeding on probing, and 3 = severe inflammation with spontaneous bleeding. Higher scores indicate worse gingival health. |
| Clinical Performance of CAD/CAM Endocrowns using FDI Criteria | 1 week (Baseline), 6 months, and 12 months post-treatment | The clinical quality and success of the Cerasmart 270 hybrid ceramic endocrown restorations will be evaluated by two calibrated independent examiners using the World Dental Federation (FDI) criteria\[cite: 1\]. The assessment covers functional criteria (retention, fracture, marginal adaptation, proximal contact), biological criteria (secondary caries, tooth integrity), and aesthetic criteria (color match, surface gloss) using a 5-point scoring system. Clinical Performance of CAD/CAM Endocrowns using FDI Criteria: Clinical performance is assessed using the FDI World Dental Federation Clinical Criteria for the Evaluation of Direct and Indirect Restorations. Each criterion is scored on a 5-point scale (1-5), where 1 = clinically excellent/very good, 2 = clinically good, 3 = clinically satisfactory, 4 = clinically unsatisfactory but repairable, and 5 = clinically poor (replacement required). Higher scores indicate worse clinical performance of the restoration. |
Countries
Turkey (Türkiye)
Contacts
STUDY_DIRECTORŞükran Bolay, Prof.
Hacettepe University
PRINCIPAL_INVESTIGATORBüşra Kara Yıldız
Hacettepe University
Outcome results
None listed