Basic Study of Fabricating Biomorphic Crowns

NCT02609178 | Completed Results DMC

• 1 other identifier: IRB-REV-2015039
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to compare among different designs of the occlusal surface of artificial crowns, trying to determine a guidance of fabricating artificial crowns with better mimesis of the original tooth crown in terms of morphology.

Conditions

Dental Crown; Prosthesis

Keywords

artificial crown; biomorphic; functional generated path; muscle-action theory; anatomic theory

Outcome Measures

Primary Outcomes (2)

• △OT Value

  Occlusion time (OT) is defined as the time from the first contact of occluding teeth to maximum intercuspation. OT is directly related with patients' occlusal contact pattern; and some have considered it as a capable description of occlusion. In the study, the OT value of each crown would be assessed before try-in (baseline) and immediately after try-in using T-scan (FGP, AVR, CON). Try-in procedure would be finished by the same clinician. △OT was calculated for minimizing individual difference among participants. The equation for △OT was:△OT(FGP/ AVR/ CON)= OT (FGP/ AVR/ CON)-OT(baseline)

  2 weeks(plus or minus 7 days) after tooth preparation

• △DT Value

  Disocclusion time (DT) is defined as the time from maximum intercuspation to complete disocclusion during lateral movement. DT related tooth contacts with muscle activity. Abnormities in DT would result in change of muscle activity, thus facilitate the occurrence of temporomandibular joint disorders. In the study, the DT value of each crown would be assessed before try-in (baseline) and immediately after try-in using T-scan (FGP, AVR, CON). Try-in procedure would be finished by the same clinician. △DT was calculated for minimizing individual difference among participants. The equation for △DT was: △DT(FGP/ AVR/ CON)= DT (FGP/ AVR/ CON)-DT(baseline)

  2 weeks(plus or minus 7 days) after tooth preparation

Secondary Outcomes (2)

• Occlusal Adjusting Time for Crowns

  2 weeks(plus or minus 7 days) after tooth preparation

• Likert's Scale

  2 weeks(plus or minus 7 days) after tooth preparation

Study Arms (2)

FGP design (FGP, AVR)

EXPERIMENTAL

use functional generated path to execute different occlusal surface designs of the artificial crown and evaluate its efficacy

Procedure: FGP; Procedure: AVR

conventional design (CON)

NO INTERVENTION

use conventional method to execute different occlusal surface designs of the artificial crown and evaluate its efficacy

Interventions

FGP PROCEDURE

To execute FGP technique, the occlusal surface of the interim should be back cut to leave at least 1mm occlusal space. Then apply the recording resin. Ask the subjects to close the mouth to maximum intercuspal position then perform right lateral, left lateral and protrusive movements in succession ending in maximum intercuspation position. Excessive resin then should be trimmed off and Bausch articulating paper would be used to mark the intercuspal contacts. Zinc oxide is then applied to check eccentric occlusion, trimmed off resin if there're interferences. Then the interim would be used as a copy to design the occlusal surface of the crown. (CAD/CAM)

Also known as: general

FGP design (FGP, AVR)

AVR PROCEDURE

the crowns in this group would be designed by setting virtual articulator to average mode (CAD/CAM)

Also known as: average value

FGP design (FGP, AVR)

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• single crown restoration needed in posterior quadrants
• the antagonist of the abutment tooth is purely natural or received minimum restorations that does not change its morphology too much
• no orthodontic treatment history
• stable occlusion
• no parafunctional movements existed

You may not qualify if:

• sequential crown restorations needed
• the morphology of the antagonist of the abutment tooth has been largely changed by previous treatment
• no contact exists between the abutment tooth and its antagonist
• orthodontic treatment history
• unstable occlusion
• existed parafunctional movements
• participated in other clinical studies

Sponsors & Collaborators

• Air Force Military Medical University, China: lead

Study Sites (1)

Stomatological Hospital of Fourth Military Medical University

Xi’an, Shanxi, 710032, China

Location

Related Publications (17)

• Mehl A. A new concept for the integration of dynamic occlusion in the digital construction process. Int J Comput Dent. 2012;15(2):109-23. English, German.

  PMID: 22891415 BACKGROUND

• Ikeda A, Miura H, Okada D, Tokuda A, Shinogaya T. The effect of occlusal contacts on adjacent tooth. J Med Dent Sci. 2005 Dec;52(4):195-202.

  PMID: 16669453 BACKGROUND

• Alhouri N, Watts DC, McCord JF, Smith PW. Mathematical analysis of tooth and restoration contour using image analysis. Dent Mater. 2004 Nov;20(9):893-9. doi: 10.1016/j.dental.2004.06.003.

  PMID: 15451245 BACKGROUND

• Vasconcelos FS, Neves AC, Silva-Concilio LR, Cunha LG, Rode Sde M. Influence of anatomic reference on the buccal contour of prosthetic crowns. Braz Oral Res. 2009 Jul-Sep;23(3):230-5. doi: 10.1590/s1806-83242009000300002.

  PMID: 19893955 BACKGROUND

• Kohal RJ, Gerds T, Strub JR. Effect of different crown contours on periodontal health in dogs. Clinical results. J Dent. 2003 Aug;31(6):407-13. doi: 10.1016/s0300-5712(03)00070-8.

  PMID: 12878023 BACKGROUND

• Takada J, Ono T, Miyamoto JJ, Yokota T, Moriyama K. Association between intraoral pressure and molar position and inclination in subjects with facial asymmetry. Eur J Orthod. 2011 Jun;33(3):243-9. doi: 10.1093/ejo/cjq060. Epub 2010 Sep 9.

  PMID: 20829312 BACKGROUND

• Olthoff L, Meijer I, de Ruiter W, Bosman F, van der Zel J. Effect of virtual articulator settings on occlusal morphology of CAD/CAM restorations. Int J Comput Dent. 2007 Apr;10(2):171-85. English, German.

  PMID: 17899892 BACKGROUND

• Memon S. A Comparative Evaluation of the Effect of Double Casting Technique Using Functionally Generated Path and Conventional Single Casting with Respect to Functional Articulation, Patient Satisfaction and Chair Side Time, in Single Unit Molar Teeth: An In Vivo Study. J Indian Prosthodont Soc. 2014 Dec;14(Suppl 1):119-25. doi: 10.1007/s13191-014-0379-6. Epub 2014 Jul 10.

  PMID: 26199501 BACKGROUND

• Curtis SR. Functionally generated paths for ceramometal restorations. J Prosthet Dent. 1999 Jan;81(1):33-6. doi: 10.1016/s0022-3913(99)70232-5.

  PMID: 9878972 BACKGROUND

• Wiklund L, Rossi F, Strata P, van der Want JJ. The rat olivocerebellar system visualized in detail with anterograde PHA-L tracing technique, and sprouting of climbing fibers demonstrated after subtotal olivary lesions. Eur J Morphol. 1990;28(2-4):256-67.

  PMID: 2245134 BACKGROUND

• Ender A, Mormann WH, Mehl A. Efficiency of a mathematical model in generating CAD/CAM-partial crowns with natural tooth morphology. Clin Oral Investig. 2011 Apr;15(2):283-9. doi: 10.1007/s00784-010-0384-z. Epub 2010 Feb 9.

  PMID: 20143242 BACKGROUND

• Becker CM, Kaldahl WB. Current theories of crown contour, margin placement, and pontic design. 1981. J Prosthet Dent. 2005 Feb;93(2):107-15. doi: 10.1016/j.prosdent.2004.11.005. No abstract available.

  PMID: 15674218 BACKGROUND

• Hazen SP, Osborne JW. Relationship of operative dentistry to periodontal health. Dent Clin North Am. 1967 Mar:245-54. No abstract available.

  PMID: 5225601 BACKGROUND

• Yuodelis RA, Weaver JD, Sapkos S. Facial and lingual contours of artificial complete crown restorations and their effects on the periodontium. J Prosthet Dent. 1973 Jan;29(1):61-6. doi: 10.1016/0022-3913(73)90140-6. No abstract available.

  PMID: 4564800 BACKGROUND

• Koidis PT, Burch JG, Melfi RC. Clinical crown contours: contemporary view. J Am Dent Assoc. 1987 Jun;114(6):792-5. doi: 10.14219/jada.archive.1987.0189.

  PMID: 3301975 BACKGROUND

• Parkinson CF. Excessive crown contours facilitate endemic plaque niches. J Prosthet Dent. 1976 Apr;35(4):424-9. doi: 10.1016/0022-3913(76)90010-x.

  PMID: 1062611 BACKGROUND

• Cho SH, Chang WG. Mirror-image anterior crown fabrication with computer-aided design and rapid prototyping technology: a clinical report. J Prosthet Dent. 2013 Feb;109(2):75-8. doi: 10.1016/S0022-3913(13)60018-9.

  PMID: 23395331 BACKGROUND

Results Point of Contact

• Title: Pingting Lin, PhD
• Organization: Stomatological Hospital of FMMU

biu79@hotmail.com

+86 15249049902

Study Officials

• Jihua Chen, PhD

  Stomatological Hospital of FMMU

  STUDY CHAIR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Dean, Professor

Study Record Dates

• First Submitted: November 16, 2015
• First Posted: November 20, 2015
• Study Start: December 1, 2015
• Primary Completion: March 1, 2016
• Study Completion: March 1, 2016
• Last Updated: August 2, 2016
• Results First Posted: August 2, 2016

Record last verified: 2016-06

Locations

CN (1)