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

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

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.

Study Overview

• Status: Completed
• Conditions: Esthetics; Angulated Screw-retained
• Intervention / Treatment: Device: angulated screw retained crown; Device: cemented crown

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Shanghai
    • Shanghai, Shanghai, China, 200011
      • Jun-Yu Shi

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: TRIPLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: angulated screw-retained group(AG)	Device: angulated screw retained crown; ASC abutment was used in AG;
ACTIVE_COMPARATOR: cemented group (CG)	Device: cemented crown; prefabricated Ti abutment was used in CG

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Marginal bone loss	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	1year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Survival rate.	Survival rates were defined as the percentage of success implants and remained crowns which never been replaced	1 year
Pro-inflammatory cytokinesin peri-implant crevicular fluid (PICF)	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.	1 year
Mechanical complications	Abutments or implants fracture and screw loosening or fracture	1 year
pocket probing depth(PD)	The depth of 6 sites（mesial, middle and distal of buccal/lingual ） was measured and the average value was calculated.	1 year
PES/WES	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).	1 year
Patient's satisfaction	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).	1 year
bleeding on probing% (BOP%)	The BOP of 6 sites（mesial, middle and distal of buccal/lingual ） was probed and the percentage of BOP(+) was calculated.	1 year
modified plaque index (mPI)	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.	1 year

Collaborators and Investigators

• Sponsor: Junyu Shi

Study record dates

Study Major Dates

• Study Start (ACTUAL): August 1, 2018
• Primary Completion (ACTUAL): August 1, 2019
• Study Completion (ACTUAL): August 1, 2020

Study Registration Dates

• First Submitted: September 1, 2020
• First Submitted That Met QC Criteria: September 4, 2020
• First Posted (ACTUAL): September 7, 2020

Study Record Updates

• Last Update Posted (ACTUAL): September 7, 2020
• Last Update Submitted That Met QC Criteria: September 4, 2020
• Last Verified: September 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: sh9th-20-09

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No