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Randomized Controlled Clinical Trial of CAD/CAM and Conventionally Fabricated Singl Implant Abutments.

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified October 2010 by Harvard School of Dental Medicine.
Recruitment status was:  Active, not recruiting
Information provided by:
Harvard School of Dental Medicine Identifier:
First received: October 27, 2010
Last updated: NA
Last verified: October 2010
History: No changes posted

CAD/CAM technology has been introduced to the field of implant dentistry in the beginning of 1990's (Priest 2005). Since their introduction, the use of CAD/CAM technology in the production of dental implant restorations has been rapidly expanding. However, little evidence is currently present supporting its clinical viability (Henriksson 2003, Canullo 2007).

Therefore, the suggested prospective randomized study includes bone level placed Straumann implants restored with transmucosal elements and crowns fabricated using either CAD/CAM "Etkon" technology (Zirconia abutment and ceramic crown) or a conventional technique (Crossfit titanium abutment and a ceramometal crown).

The aim of this randomized controlled clinical trial is to examine single-tooth implant restorations in the esthetic zone. An esthetic area is defined as any area that is visible in the patient's full smile. [3rd ITI consensus conference 2004] The rehabilitations will be fabricated using two different techniques. Zirconia CAD/CAM (ZCC) implant restorations (tests) will be compared to Titanium conventionally-fabricated (TCF) implant restorations (controls) using, reproducible esthetic (objective/subjective) and biologic parameters.

This in vivo study is a randomized study with two groups of 15 patients with one implant each for a total of 30 patients and 30 implants. The implants will be examined for successful tissue integration according to the criteria of success (Buser et al. 1990) at every recall visit.

In addition, the following parameters will be evaluated for each restoration:

  • Esthetic: A. Objective: PES/WES Score (Belser et al. 2009) from 1:1 digital photograph, study casts, and spectrophotometric measurements, and B. Subjective: VAS questionnaire for patients and VAS questionnaire from experts.
  • Biologic (mPI, mB, simplified GI, microbial sample, periapical radiograph for DIB, and width of keratinized facial mucosa)

Finally, an evaluation of the mechanical, biologic and technical complications will be performed at every recall visit. Mechanical complications would be defined as those complications that involve the prosthesis such as abutment screw loosening, fracture of the veneer material, fracture of the crown framework, abutment screw fractures, and implant fractures. The category of biologic complications will include those complications that involve the soft tissues (e.g., fistula, suppuration, bleeding, gingival inflammation, and soft tissue dehiscence). Technical complications are defined as those related to restorative components and crowns (e.g. crown emergence profile, abutment and crown fit, screw loosening, ceramic fracture).

Condition Intervention
Missing Teeth
Teeth Replacemnt by Single Dental Implant
Zirconia Abutment
Titanium Abutment
Device: dental implants - zirconia abutmetns - prefabricated abutments

Study Type: Interventional
Study Design: Allocation: Randomized
Official Title: A Comparison of Zirconia CAD/CAM and Conventionally Fabricated Single Implant Abutments and Restorations in the Esthetic Zone: a Randomized Controlled Clinical Trial.

Resource links provided by NLM:

Further study details as provided by Harvard School of Dental Medicine:

Primary Outcome Measures:
  • The aim of this randomized controlled clinical trial is to examine single-tooth implant abutments and restorations in the esthetic zone.

Secondary Outcome Measures:
  • Test group will achieve better biologic and esthetic outcomes when compared to control group

Enrollment: 30
Study Start Date: May 2009
Arms Assigned Interventions
Active Comparator: Prefabricated Abutment Device: dental implants - zirconia abutmetns - prefabricated abutments

  Show Detailed Description


Ages Eligible for Study:   21 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

Inclusion Criteria:


  1. Age > 21 years
  2. Absence of relevant medical conditions
  3. Absence of periodontal diseases
  4. The opposing dentition must be natural teeth or fixed (not removable) restorations on teeth or implants.
  5. Availability for 5-year follow-up


  1. One missing tooth in the esthetic zone. An esthetic area is defined as any area that is visible in the patient's full smile. [3rd ITI consensus conference 2004]
  2. Presence of two intact adjacent teeth which are either non-restored or with minor restorations (small composite restorations)
  3. Adequate native bone to achieve primary stability
  4. Adequate band of keratinized mucosa (at least 2mm)
  5. Full Mouth Plaque Scores (FMPS) and Full Mouth Bleeding Scores (FMBS) < 25 %

Exclusion Criteria:

Exclusion criteria


  1. Heavy smokers (more than 10 cigarettes/day)
  2. Presence of conditions requiring chronic prophylactic use of antibiotics
  3. Medical conditions requiring prolonged use of steroids.
  4. History of radiation therapy to the head or neck or history of chemotherapy.
  5. Physical handicaps that would interfere with the ability to perform adequate oral hygiene.
  6. Patients with inadequate oral hygiene.


1. Adjacent implant 2. Presence of periapical radiolucencies at the adjacent teeth 3. Missing adjacent teeth 4. Local inflammation, including untreated periodontitis. 5. Persistent intraoral infections. 6. Untreated mucosal diseases.

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01229995

Sponsors and Collaborators
Harvard School of Dental Medicine
Principal Investigator: German O. Gallucci, DMD Dr.Med.Dent. Harvard School of Dental Medicine
  More Information

Responsible Party: German O. Gallucci, Harvard School of Dental Medicine Identifier: NCT01229995     History of Changes
Other Study ID Numbers: M17719-104
Study First Received: October 27, 2010
Last Updated: October 27, 2010

Additional relevant MeSH terms:
Tooth Loss
Periodontal Diseases
Mouth Diseases
Stomatognathic Diseases
Tooth Diseases
Tooth Abnormalities
Stomatognathic System Abnormalities
Congenital Abnormalities processed this record on May 25, 2017