ClinicalTrials.gg
RecruitingNCT06496828Updated Sep 1, 2026

Clinical Outcomes of Biologically Oriented Preparation Technique

An interventional study of Biologically-oriented preparation technique and Conventional method of preparation in Crowns and Tooth Preparation, sponsored by Damascus University. Recruiting at 1 site in Syria. Open to participants aged 19 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-09-01.

Sponsored by Damascus University · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Started Apr 2024; still recruiting 2 years 6 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
60
Allocation
Randomized
Ages
19 Years to 80 Years
Sex
All
01

Study summary

This study aims to evaluate the periodontal response of teeth prepared with a biologically oriented preparation technique (BOPT) compared to conventional preparation for all-ceramic crowns.

Read the detailed description

The study aims to evaluate the clinical performance of all-ceramic crowns on teeth prepared with two different types of preparations.

This randomized controlled trial will include 60 teeth divided into two groups: 30 teeth will be prepared with BOPT, and 30 teeth will be prepared with shoulder margins. All teeth will receive monolithic or bi-layered ceramic crowns.

Patients are planned to attend follow-up visits after 3, 6, 12, and 18 months, respectively, after cementation. Probing depth, gingival recession, bleeding on probing, gingival index, gingival thickness, patient opinion, and mechanical and biological complications are all recorded at check-up appointments.

02

Conditions studied

  • Crowns
  • Tooth Preparation
03

In context

Lead sponsor

Damascus University is the lead sponsor of 212 studies on the registry; 11 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
19 Years to 80 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Patients older than 18.
  • Two teeth at least needed to be restored with full crowns (each patient needs at least two single crowns).
  • Stable occlusion.
  • Good oral hygiene.
  • Periodontally healthy teeth.
  • Nonsmoking or smoking less than ten cigarettes/day.
  • Probing depth between 1 and 3 mm.

Exclusion criteria

Exclusion Criteria:

  • Patients younger than 18.
  • Parafunctional habits.
  • Active periodontal disease.
  • Poor oral hygiene.
  • Systemic disease that may affect the periodontal health.
  • Pregnancy.
  • Radiation or chemotherapy.
  • Treatment by Bisphosphonates medication.
  • Patients who are unable or unwilling to attend follow-up visits
05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Outcomes assessor)
Enrollment
60 participants (estimated)

Study arms

  • Experimental
    Biologically-oriented preparation technique (BOPT)

    Patients in this group will undergo the biologically-oriented preparation technique.

    Procedure: Biologically-oriented preparation technique

  • Active comparator
    Conventional preparation

    Patients in this group will undergo the convention preparation technique.

    Procedure: Conventional method of preparation

Interventions

  • ProcedureBiologically-oriented preparation technique

    The preparation will be made according to the new principles of biologically oriented technique to receive monolithic and bi-layered all-ceramic crowns.

  • ProcedureConventional method of preparation

    Teeth prepared with shoulder margins to receive monolithic and bi-layered all-ceramic crowns

06

What researchers measure

Primary outcomes

  1. Change in the Plaque index

    The plaque index will be measured at the buccal, lingual, mesial, and distal sites of each included tooth, according to Löe and Silness, 1963

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation of the crowns.

  2. Change in the gingival index

    The gingival index will be measured at the buccal, lingual, mesial, and distal sites of each included tooth according to Silness and Löe, 1964

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation of the crowns.

  3. Change in the probing depth

    A UNC periodontal probe will be used to measure the probing depth at the buccal, lingual, mesial, and distal sites of each included tooth.

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation of the crowns.

  4. Change in bleeding on probing

    This variable will be measured at the buccal, lingual, mesial, and distal sites of each included tooth, recorded simultaneously with probing depth, according to Ainamo and Bay, 1975

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation of the crowns.

  5. Change in the gingival marginal stability

    The gingival marginal stability at the buccal site will be measured using a UNC periodontal probe and a transparent jig to measure the distance between a reference point on the jig and the free gingival margin.

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation of the crowns.

  6. Change in the free gingiva thickness

    The free gingiva thickness will be measured at the buccal site using a transparent jig with a reference point on the marginal gingiva, a 15-size spreader with a rubber stopper, and a millimetric ruler

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation of the crowns.

Secondary outcomes

  1. Change in the internal and marginal adaptation

    The internal and marginal adaptation will be dong using the replica technique. It will be carried out after clinical assessment and cementation of all crowns. An in vitro study utilizing an optical microscope with a micron-graded ruler will be implemented.

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation.

  2. Change in the functional and mechanical complications

    The functional and mechanical complications will be appraised. The existence of cracks, chipping, and/ or fracture of crowns and their size if exist according to FDI criteria (Hickel et al., 2010) will be evaluated.

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation.

  3. Change in the secondary caries status

    The secondary caries status will be assessed according to Cvar and Ryge, 2005. The presence or absence of caries at the cervical margins of the abutments will be recorded. Other biological complications, such as abutment fracture, root fracture, and/ or pulpitis will be reported, too

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation.

  4. Change in the marginal adaptation after crown cementation

    The marginal adaptation after crown cementation will be clinically evaluated using a sharp dental probe, according to Cvar and Ryge, 2005, at each follow-up appointment.

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation.

  5. Change in the color matching

    The level of color matching will be assessed according to Cvar and Ryge (2005). To measure this outcome, color matching with adjacent teeth, slight mismatching, or major mismatching of color and/or translucency will be reported.

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation.

  6. Change in the clinical success

    The clinical success status will be assessed according to Walton, 2002. This outcome will be evaluated in case any patient cannot attend the follow-up visits during the trial for any reason. Thus, success might be evaluated indirectly by a phone call if possible.

    Time frame: Will be recorded at 1 week, 1, 3, 6, 12, and 18 months after cementation.

  7. Change in patients' satisfaction

    Patients' satisfaction will be assessed according to FDI criteria (Hickel et al., 2010). This outcome will report the level of patient satisfaction functionally and aesthetically. Complete satisfaction, light criticism, major criticism, and entirely dissatisfaction are the levels of the patient's view that will be described.

    Time frame: This will be measured at one week and 18 months following cementation.

07

Study locations

1 of 1 sites recruiting
  • Department of Fixed Prosthodontics, University of Damascus Dental School, Damascus, Syria
    Damascus, DM20AM18, Syria
    Recruiting
08

References and documents

Publications

  • Mohammad A, Abraham S, Nada A. The effect of biologically oriented and subgingival horizontal preparation techniques on periodontal health: A double-blind randomized controlled clinical trial. Saudi Dent J. 2023 Sep;35(6):727-733. doi: 10.1016/j.sdentj.2023.06.003. Epub 2023 Jun 17. PubMed 37817795 ↗
  • Palombo D, Rahmati M, Vignoletti F, Sanz-Esporrin J, Salido MP, Haugen HJ, Sanz M. Hard and soft tissue healing around teeth prepared with the biologically oriented preparation technique and restored with provisional crowns: An in vivo experimental investigation. J Clin Periodontol. 2023 Sep;50(9):1217-1238. doi: 10.1111/jcpe.13825. Epub 2023 May 30. PubMed 37253614 ↗
  • Agustin-Panadero R, Serra-Pastor B, Loi I, Suarez MJ, Pelaez J, Sola-Ruiz F. Clinical behavior of posterior fixed partial dentures with a biologically oriented preparation technique: A 5-year randomized controlled clinical trial. J Prosthet Dent. 2021 Jun;125(6):870-876. doi: 10.1016/j.prosdent.2020.03.031. Epub 2020 Jun 21. PubMed 32580920 ↗
  • Serra-Pastor B, Bustamante-Hernandez N, Fons-Font A, Fernanda Sola-Ruiz M, Revilla-Leon M, Agustin-Panadero R. Periodontal Behavior and Patient Satisfaction of Anterior Teeth Restored with Single Zirconia Crowns Using a Biologically Oriented Preparation Technique: A 6-Year Prospective Clinical Study. J Clin Med. 2021 Aug 6;10(16):3482. doi: 10.3390/jcm10163482. PubMed 34441778 ↗
  • Agustin-Panadero R, Serra-Pastor B, Fons-Font A, Sola-Ruiz MF. Prospective Clinical Study of Zirconia Full-coverage Restorations on Teeth Prepared With Biologically Oriented Preparation Technique on Gingival Health: Results After Two-year Follow-up. Oper Dent. 2018 Sep/Oct;43(5):482-487. doi: 10.2341/17-124-C. Epub 2018 Mar 7. PubMed 29513640 ↗
  • Paniz G, Nart J, Gobbato L, Chierico A, Lops D, Michalakis K. Periodontal response to two different subgingival restorative margin designs: a 12-month randomized clinical trial. Clin Oral Investig. 2016 Jul;20(6):1243-52. doi: 10.1007/s00784-015-1616-z. Epub 2015 Oct 8. PubMed 26445857 ↗
  • Loi I, Di Felice A. Biologically oriented preparation technique (BOPT): a new approach for prosthetic restoration of periodontically healthy teeth. Eur J Esthet Dent. 2013 Spring;8(1):10-23. PubMed 23390618 ↗

Individual participant data

Plan to share: No

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 1, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06496828
Responsible party
Sponsor
First posted
Jul 11, 2024
Start date
Apr 30, 2024
Primary completion
Dec 30, 2026 (estimated)
Completion
Dec 30, 2027 (estimated)
Last update
Sep 1, 2026

Study contacts

Abeer Aljareh, DDS MSc
Contact
abeer12.jareh@damascusuniversity.edu.sy
00963967873566
Nabil Alhouri, DDS MSc PhD
Contact
nabil.alhouri@damascusuniversity.edu.sy
00963944597722
Abeer Aljareh, DDS MSc
principal investigator · Department of Fixed Prosthodontics, Faculty of Dentistry, Damascus University, Damascus, Syria
Nabil Alhouri, DDS MSc PhD
study director · Department of Fixed Prosthodontics, Faculty of Dentistry, Damascus University, Damascus, Syria
Mohanad Kadhim, DDS MSc PhD
study director · Department of Periodontology, Faculty of Dentistry, Iraq.

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion