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.


Objectives: To evaluate the clinical behavior of one-piece complete-coverage crowns and fixed partial dentures (FPDs) on teeth with vertical preparation without finish line biologically oriented preparation technique (BOPT).

Methods and materials: This prospective study included 52 patients requiring treatment with restorations in the esthetic region: 74 crowns and 27 FPDs. The sample included a total of 149 teeth that were prepared vertically without finish line. The sample was divided into two groups: one-piece crowns and FPDs, all with zirconia cores, feldspathic ceramic veneer, and a 0.5-mm prosthetic finish line of zirconia. All procedures were carried out at the University of Valencia from 2013 to 2014. The following parameters were evaluated over a two-year follow-up: oral hygiene, periodontal state, gingival thickening, gingival margin stability, the presence of complications, and restoration survival rate. Patient satisfaction with treatment was assessed by means of a visual analogue scale (VAS).

Results: Two years after treatment, 80.5% of treated teeth remained free of gingival inflammation and bleeding. Mean gingival thickening was 0.41 ± 0.28 mm for one-piece crowns and 0.38 ± 0.36 mm for FPDs. Gingival margin stability was 100%, but 2% of the sample presented biological complications. The VAS patient satisfaction scores were eight out of a maximum score of 10.

Conclusions: Two years after treatment, vertical preparation without finish line produces gingival thickening, margin stability, and optimal esthetics. Neither crowns nor FPDs presented any mechanical complications.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Ceramics / adverse effects
  • Ceramics / therapeutic use
  • Crowns* / adverse effects
  • Dental Restoration, Permanent / adverse effects
  • Dental Restoration, Permanent / methods*
  • Esthetics, Dental
  • Female
  • Follow-Up Studies
  • Gingiva / drug effects
  • Gingival Diseases / etiology*
  • Gingival Diseases / prevention & control
  • Humans
  • Male
  • Middle Aged
  • Patient Satisfaction
  • Prospective Studies
  • Young Adult
  • Zirconium / adverse effects
  • Zirconium / therapeutic use*


  • Zirconium
  • zirconium oxide