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Completed

NCT Number: NCT04539912

Clinical Efficacy of Angulated Screw-retained and Cemented Single Implant Crowns in Esthetic Region

Objective: To compare the clinical efficacy of angulated screw-retained and cemented single implant crowns(SIC) in esthetic region.

Methods/Design: The study was a prospective, single center, randomized controlled clinical trial. Patients with the needs of single tooth restoration in esthetics region were recruited from Oct. 2018 to Aug. 2019. Sixty patients were enrolled in the present study and they were randomly assigned into two groups: angulated screw-retained group(AG, 30 patients) and cemented group (CG,30 patients). Clinical and radiological evaluations were performed on the day of final crowns delivery and 12 months later. Implant survival rate, marginal bone loss(MBL), pro-inflammatory cytokinesin peri-implant crevicular fluid (PICF)(TNF-α, IL-6), mechanical complications, peri-implant conditions(mPI, PD, BOP%), pink esthetics score/white esthetics score (PES/ WES) and patients satisfaction were assessed.

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Key information

Conditions

Angulated Screw-retained Esthetics

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Jun-Yu Shi

Shanghai, Shanghai Municipality, 200011, China

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • 1) age≥18;
  • 2) Single dental implant in the esthetic region;
  • 3) adjacent to natural teeth;
  • 4) absence of oral mucosal disease and oral infection;
  • 5)implants withconical connection (Nobel Active, Nobel Biocare® or NobelReplace Conical Connection, Nobel Biocare®);
  • 6)patients with the willingness of all-ceramic permanent restorations.

Exclusion criteria

  • 1)Multiple implants in the esthetic region, or the restoration is a bridge;
  • 2)Heavy smokers (>10 cigarettes/day);
  • 3) the angle between implant axis and restoration axis>25°;
  • 4) uncontrolled periodontitis;
  • 5) with systematic diseases that may affect implant therapy, such as uncontrolled diabetes mellitus (Fasting blood-glucose>7.2mmol/L, Glycosylated hemoglobin >7%), current intake of bisphosphonates (treatment for malignancy), pregnant(or plan to get pregnant), with history of radiation therapy in head and neck region;
  • 6) Unwilling to participate in the present study.

Treatment and study plan

angulated screw retained crown

Device

ASC abutment was used in AG;

cemented crown

Device

prefabricated Ti abutment was used in CG

Primary outcomes

  1. Marginal bone loss

    Time frame: 1year

    Peri-apical radiographs with paralleling technique wereperformed on the day offinal restorations delivery and 1-year visit. Implant length was used as calibration reference. The distance between restoration margin and the most coronal level of implant-bone contactwas recorded. Final result was calculated as themean value of the mesial and distal sites

Secondary outcomes

  1. Survival rate.

    Time frame: 1 year

    Survival rates were defined as the percentage of success implants and remained crowns which never been replaced

  2. Pro-inflammatory cytokinesin peri-implant crevicular fluid (PICF)

    Time frame: 1 year

    we collected the patients' PICF with the paper strip (PerioPaper Strips; Oraflow Inc., Smithtown, NY, USA) at 1year follow-up to access differences in pro-inflammatory cytokines (IL-6 and TNF-α) between two groups.

  3. Mechanical complications

    Time frame: 1 year

    Abutments or implants fracture and screw loosening or fracture

  4. pocket probing depth(PD)

    Time frame: 1 year

    The depth of 6 sites（mesial, middle and distal of buccal/lingual ） was measured and the average value was calculated.

  5. PES/WES

    Time frame: 1 year

    specific dentists were asked to give scores for variables of PES (Mesial papilla, distal papilla, level of soft-tissue margin, soft-tissue contour, alveolar process and soft-tissue color and texture) and WES (Tooth form, tooth volume/outline, color, surface texture and transparency) with the 2-1-0 scoring system. Final PES/WES was the sum the two. Total scores were defined as perfect rate (PES/WES≥22), acceptable rate (22>PES/WES≥15) and unfavorable rate (PES/WES<15).

  6. Patient's satisfaction

    Time frame: 1 year

    patient's satisfaction(PS) with aesthetics, function and comfort of the restoration at 1-year visit. 0 score was extremely dissatisfied and 10 score was extremely satisfied. We also defined the final scores as perfect rate(PS≥9), acceptable rate(9>PS≥6) and unfavorable rate (PS<6).

  7. bleeding on probing% (BOP%)

    Time frame: 1 year

    The BOP of 6 sites（mesial, middle and distal of buccal/lingual ） was probed and the percentage of BOP(+) was calculated.

  8. modified plaque index (mPI)

    Time frame: 1 year

    Score 0; No detection of plaque Score 1: Plaque only recognized by running a probe across the smooth marginal surface of the implant. Implants covered by titanium spray in this area always score 1.

    Score 2: Plaque can be seen by the naked eye. Score 3: Abundance of soft matter.

Sponsors and collaborators

Lead sponsor

Junyu Shi

Other

Registry information

Official study title

Comparison of the Short-term Clinical Efficacy of Angulated Screw-retained and Cemented Single Implant Crowns in Esthetic Region: A Randomized Controlled Clinical Trial

Important dates

Study start
2018
Primary completion
2019
Study completion
2020
First posted
Sep 7, 2020
Registry last updated
Sep 7, 2020

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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