Histological study of human periodontal tissue following biologically oriented preparation technique (BOPT)

Abstract

Background The aim of this study was to conduct histological analysis of a human tooth resected with the periodontal insertion apparatus intact following treatment using biologically oriented preparation technique (BOPT). Material and Methods This descriptive histological dento-periodontal study used an anterior tooth extracted with the surrounding periodontal tissues intact, following prosthetic restoration with BOPT. The sample patient was recruited from among those attending the Department of Dental Medicine at the Faculty of Medicine and Dentistry, University of Valencia (Spain). Eight serial sections of the restored tooth were processed. The relative location and histological characteristics of the cemented prosthetic crown, the dental tissues of the tooth prepared by BOPT technique, and the periodontal tissues were analyzed. Results Structural analysis of the neoformed junctional epithelium showed that the number of layers decrease apically until there was a single row of cells perfectly adhered to the acellular cementum, and beneath the epithelium a connective tissue evidently free from inflammation. The tissues of the neoformed periodontium (gingival ligament, sulcular epithelium, junctional epithelium) presented histologic normality. Conclusions Biologically oriented preparation technique is a reliable alternative to conventional horizontal finish lines. Key words: Vertical preparation, prosthetic cementoenamel junction (PCEJ), finish line, BOPT, crown.

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

“…It is necessary to detach the whole epithelium in order to produce re-epithelialization and renewed periodontal attachment. All the epithelium attached to the tooth, as far as the connective tissue, was detached to provoke bleeding and the production of blood coagulate that would promote cell differentiation and renewed periodontal attachment [24]. The second step consists of placing the bur parallel to the tooth's axis (at an angle of 0 • ) inside the sulcus.…”

“…The provisional crowns were designed with a cervical emergence at 45 • to the cervical emergence of the tooth axis. For correct tissue maturation, it is crucial to stabilize the coagulate by means of the provisional crown's cervical emergence [24]. After the provisional phase, impressions were taken to fabricate the definitive crown.…”

“…The technique eliminates the tooth's anatomical crown emergence at the cementoenamel junction (CEJ) to make room for the creation of a new emergence profile by the prosthetic crown. At the same time, rotary curettage of the gingival sulcus is performed [24][25][26][27][28]. The technique was inspired by periodontal prosthetic protocols of the 1980s and 1990s, such as rotary curettage and knife-edge dental preparation [8,14,15].…”

“…This provokes bleeding in the area, which will subsequently produce a blood coagulate that fills the area of the supracrestal attached tissue. This is subsequently stabilized by the new prosthetic emergence, whereby the coagulate is replaced in time by mature connective tissue, causing new structuring and attachment [16,24,25,[29][30][31][32]. In this way, with the help of the provisional prosthesis, the surrounding soft tissues are modified in shape and position, adapting to the shape of the new prosthetic emergence.…”

Influence of Angulation in Cervical Prosthetic Emergences Relative to the Gingival Tissue of Teeth Treated under the Biologically Oriented Preparation Technique (BOPT)

“…In this stage, new blood vessels are created, and fibroblasts and myofibroblasts of the degranulation tissue grow and occupy the space created by the rotatory curettage. Then, there is a contraction of the myofibroblasts around the tooth; furthermore, thanks to the conical dental preparation, a migration of the soft tissues towards the crown occurs (from the area of greatest diameter (apical) to the area of the smallest diameter (coronal)) [16,17]. This stage has been described as one where tissue growth takes place via a transduction mechanism [18,19].…”