The biologically oriented preparation technique (BOPT) approach for preventing gingival recessions in fixed prosthodontics. A 5- to 13-year follow-up retrospective study.

AIM: The present study was a retrospective medium- to long-term follow-up assessment of the clinical outcomes of patients rehabilitated with fixed prostheses according to the biologically oriented preparation technique (BOPT) principles. MATERIALS AND METHODS: Clinical records of patients rehabilitated between January 2007 and December 2014 were retrospectively assessed. Patients whose records met the inclusion criteria were also recalled for a hygiene visit. Data analyzed included the patients' periodontal condition, the presence of gingival recessions as well as any technical or biologic prosthetic complication. RESULTS: Fifty-eight patients were recalled; of these, 52 patients who had received 220 crowns were available for the evaluation (the dropout being 13.8%). The average follow-up was 9.3 years (range 5 to 13 years): 14 patients (114 prosthetic crowns) had a follow-up between 5 and 8 years, and 36 patients (106 prosthetic crowns) between 9 and 13 years. The prosthetic survival rate was 99.6%. One radicular fracture (0.4%) and four chippings of the veneering porcelain (1.8%) were recorded. Six teeth (2.7% of the examined prosthetic crowns) presented gingival recession of < 1 mm, and 13 teeth (24 sites) had a pocket probing depth of 4 mm (5.9% of the prosthetic crowns/1.8% of the sites). Finally, 20 sites (1.5%) in seven teeth (3.2%) showed bleeding on probing. CONCLUSIONS: Tooth preparation according to the BOPT principles (ie, with a vertical finishing line) resulted in medium- to long-term periodontal health and stability of the gingival tissue, and prosthetic success was maintained.

An Enigmatic Soft-Tissue Creeping Phenomenon: The Spontaneous Peri-Implant Mucosa Margin and Papilla Growth, Part Two-A Scientifically Supported Hypothesis Article.

In our previous article, we observed and measured a spontaneous growth in the coronal direction of the keratinized tissues present around implants. This growth involved both free margins and interdental papillae, and we indicated our hypothesis on the probable cause of this still-unexplained phenomenon. The growth of oral soft tissues involves several other structures, such as the linea alba and tongue indentation. Our idea holds that growth of these tissues is generated by the negative intraoral pressure created in the oral phase of swallowing and the subsequent resting position, which through the resulting suction causes a shift of these soft structures in the gaps around the dental crowns. Other hypotheses have been suggested in the past to understand this phenomenon of soft tissue growth, which still lacks data supporting etiological evidence. The purpose of this article is to thoroughly analyze and verify our model by comparing the clinical observations with citations and examples from the literature, combined with notions of physiology, biology, and physics that help in clarifying these events. To better explain the mechanisms of oral soft tissue growth, photographs of clinical cases paradigmatic of the phenomenon are shown.

Comparative Effect of No Finish Line, Heavy Chamfer, and Shoulder Marginal Designs on the Fracture Resistance of Zirconia (Cercon) Ceramic Restoration: An In Vitro Study.

Background Because all-ceramic crowns are more aesthetic and biocompatible than metal-ceramic crowns, they have grown in popularity among patients and dentists. Poor finish line layout can result in restoration margin fracturing, hence, finish line arrangement is critical to maintaining the restoration's marginal integrity. The goal of this in-vitro study is to evaluate zirconia's resistance to fracture (Cercon) ceramic restorations with three marginal designs (no finish line, heavy chamfer, and shoulder). This study is important in contributing to the ongoing debate about the optimal finish line design for zirconia restorations. Methodology Three different finish lines, namely, biologically oriented preparation technique (BOPT) with a marginal width of less than 0.3 mm, heavy chamfer with a marginal width of up to 0.3 mm, and shoulder with a marginal width greater than 0.3 mm, were made on 10 extracted maxillary first premolar tooth to make 30 epoxy resin dies on which zirconia (Cercon) coping was done using CAD/CAM technology, and marginal discrepancies were measured using a three-dimensional scanner. All the copings were affixed to their respective dies using GIC luting cement, and fracture resistance was measured using a digital universal testing machine. Results The Kruskal-Wallis test revealed that the mean fracture resistance was more in the heavy chamfer finish line, followed by the no finish line (BOPT) and the shoulder finish line. No statistically significant difference was seen between the no finish line and the heavy chamfer finish line. There was a significant difference between the heavy chamfer and shoulder finish lines (p = 0.004). Conclusions To increase the biomechanical performance of posterior single zirconia restorations, heavy chamfer margins are indicated.

The effect of biologically oriented and subgingival horizontal preparation techniques on periodontal health: A double-blind randomized controlled clinical trial.

Purpose: The aim of this study was to investigate and compare the influence of subgingival horizontal preparation technique (SHPT) and biological oriented preparation technique (BOPT) on periodontal health at a split-mouth model. Methods: The sample of 100 patients was divided into two groups using a spilt-mouth study design; each patient had received two crowns with SHPT and BOPT respectively. The teeth were randomly allocated for the preparation techniques. All prepared teeth were restored with fabricated zirconium cores and ceramic layering. Temporary crowns were delivered after taking an impression and patients were recalled for the final cementation of the crowns. After that, follow-up recalls were set at one month, 3 months, 6 months, one year, and two years to record the following clinical parameters; plaque index, probing depth, bleeding on probing, clinical attachment level and patients' satisfaction with treatment. Results: SHPT had significantly lower plaque and inflammation index at baseline, which increased significantly at 3 months and 2 years' follow-up compared to BOPT. Patients' satisfaction was significantly higher with SHPT at baseline, and it is reduced significantly at 6 months and two years follow- up (P < 0.001). The probing depth was significantly higher in BOPT at baseline and 3 months and decreased significantly at 6 months, 1 year, and 2 years' follow-up. Conclusion: BOPT is a favorable technique with a full crown or veneer, presenting good marginal stability and periodontal behavior.

Periodontal Healing with Fixed Restorations Using the Biologically Oriented Preparation Technique Combined with a Full Digital Workflow: A Clinical Case Report.

(1) Gingival inflammation is an ongoing challenge in tooth-supported fixed restorations, especially when the prosthetic margin does not consider the supracrestal tissues of patients. This case report aimed to present the case of a patient who was periodontally compromised due to a previous invasion of the supracrestal tissue attachment with fixed restorations and evaluate the healing response of periodontal tissues to a vertical edgeless preparation technique: bleeding upon probing (BOP), periodontal probing depth (PPD) and clinical attachment level (CAL). (2) After tooth preparation, the new restorations were adapted, this time without invading the supracrestal space of the patient, and CAD/CAM monolithic zirconia crowns were fabricated. (3) Optimal maturation of the soft tissue was observed, achieving correction of the marginal contour of periodontal tissues and improvement of periodontal indexes. (4) It can be concluded that the BOPT technique combined with a full digital workflow is a valid option for the correction and remodeling of gingival architecture.

The Influence of the Thickness of the Materials for the Provisionalization in Minimally Invasive Restorations.

This in vitro study aimed to determine the flexural strength and modulus of elasticity of two bisacrylic resins for temporary crowns at different thicknesses, i.e., Structur 3 and Structur Premium, and to compare them with each other. Sixty samples were prepared, thirty of each material, which were made at different thicknesses (1 mm, 1.5 mm, and 2 mm). The dimensions followed the UNE-EN ISO 178:2019 standard, with a length of 24 mm, a width of 10 mm, and the thicknesses described. Materials were subjected to a three-point bending test. For the modulus of elasticity, statistically significant differences were observed between the 1.5 mm and 2 mm thicknesses of Structur 3 material. For Structur Premium, statistically significant differences were observed between the thicknesses 1 mm and 1.5 mm as well as between 1 mm and 2 mm thickness. With respect to flexural strength, no statistically significant differences were observed for either material at the different thicknesses. Significant differences were observed between the materials for both flexural strength and modulus of elasticity, being higher for Structur Premium: Structur Premium has a higher flexural strength and modulus of elasticity than Structur 3. There are significant differences for the modulus of elasticity but not for the flexural strength between thicknesses.

Clinical Behavior of the Gingival Margin following Conservative "Coronally Dynamic" Restorations in the Presence of Non-Carious Cervical Lesions Associated with Gingival Recession: A Pilot Study.

Gingival recessions (GR) are often associated with the presence of non-carious cervical lesions (NCCL). The latter result in the disappearance of the cement-enamel junction (CEJ), with consequent difficulties both in measuring the recession itself and in performing root coverage techniques. The restoration of cervical lesions is consequently an important aspect in the treatment of GR, with the re-establishment of a "new" CEJ. This pilot study aimed to verify whether restorative therapy alone, with the execution of a restoration that mimics the convexity of the natural CEJ and thanks to a slight horizontal over-contour, can stabilize a clot in the intrasulcular site and consequently is able to change the position of the gingival margin in a coronal direction. In periodontally healthy patients, with a non-thin gingival phenotype, 10 GR-associated NCCL restorations were performed using a protocol inspired by concepts of prosthetic conditioning, with a progressively reduced convexity ("coronally dynamic restoration") and de-epithelialization of the gingival sulcus. We observed that 70% of the treated teeth showed a reduction in crown length after 15 days (-0.267 mm), without an increase in probing depth. While considering the limitations of the sample and the need to evaluate the different parameters that can affect the result, the coronally dynamic restoration of NCCL with GR was able to influence the position of the gingival margin in a coronal direction.

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.

OBJECTIVES: The aim of this study was to analyze the behavior of the periodontal tissues around teeth in the anterior region when restored with zirconia single crowns, using a biologically oriented preparation technique (BOPT), over a 6-year follow-up. METHODS: The study investigated tooth-supported single crowns in the anterior region that were fabricated with a zirconia core and feldspathic ceramic covering, in 34 patients. Follow-up analysis took place annually for 6 years, assessing periodontal responses by evaluating the following variables: plaque index (PI); probing depth (PD); gingival index (GI); gingival thickness adjacent to the restoration; and stability of the gingival margin (MS). Any (biological and mechanical) complications were also recorded, as well as the patients' satisfaction with the treatment. RESULTS: After 6 years' follow-up, a low mean plaque index was obtained, probing depth was stable, and gingival thickness and margin stability had increased. Complications (biological and mechanical) did not present a statistically significant incidence and a crown survival rate of 97.2% was achieved. Patients' satisfaction obtained a mean VAS score of 9.04 under 10. CONCLUSION: Teeth that are prepared with BOPT in the anterior region present good periodontal behavior around the restored teeth, particularly in terms of the stability of the gingival margin and increased gingival thickness. Single crowns prepared with BOPT obtain an excellent clinical survival rate, as well as a high score in patients' satisfaction after 6 years.

New Generation of Fixture-Abutment Connection Combining Soft Tissue Design and Vertical Screw-Retained Restoration: 1-Year Clinical, Aesthetics and Radiographic Preliminary Evaluation.

Implant design factors and the abutment connection are correlated with crestal bone stability. The aim of the present study was to evaluate a new type of screw-retained prostheses delivered on tissue-level implants with conical external vertical seal and internal hexagon connection. Implants 4.25 mm in diameter and 10 mm in length (Prama, Sweden and Martina) were placed in partially edentulous patients needing at least one implant in the healed site, having sufficient bone volume. The implant neck was positioned above the bone crest. A healing abutment was placed according to a one-stage approach. Outcome measures were implant and prosthesis survival rate, any complications, marginal bone loss (MBL), periodontal parameters, and pink esthetic score (PES). Overall, 13 patients (4 women and 9 men; mean age 50 ± 22 years) with the same number of implants were treated and followed for one year after loading. At the 12-month follow up, no implant and no prosthesis failed, and no complications were experienced. The mean MBL experienced at the one year follow-up was 0.65 ± 0.48 mm. One year after loading, 2 out of 13 implants present bleeding on probing (15.4%), 4 out of 13 patients presented with plaque at the one year of follow-up (30.8%) and the PES was 10.5 ± 2.3 mm. Within the limitations of the present study, the analyzed implants seem to be a viable treatment option for the rehabilitation of a single tooth gap.

Analogical and Digital Workflow in the Design and Preparation of the Emergence Profile of Biologically Oriented Preparation Technique (BOPT) Crowns over Implants in the Working Model.

: The Biologically Oriented Preparation Technique (BOPT), developed by Ignacio Loi and published in 2008, is a consolidated concept in the modeling and preservation of pericoronal soft tissues. The present study describes the analogical and digital methods allowing adequate design and preparation of the emergence profile of BOPT crowns in the working model, with a view to comparing the workflow and advantages of each method. At present, not all the digital procedures have been fully optimized to completely replace the traditional analogical methods. Nevertheless, it is only a matter of time until dental digitalization technology totally replaces the analogical clinical methods. The digital workflow for this procedure is quickly implemented and optimized, and represents the most realistic option, with possibilities for further development in the immediate future.

Periodontal and prosthetic outcomes on teeth prepared with biologically oriented preparation technique: a 4-year follow-up prospective clinical study.

PURPOSE: To evaluate the clinicaland biological behavior of full coverage restorations on teeth prepared without finish line during a 4-year follow-up. METHODS: This prospective study included 149 teeth treated using biologically oriented preparation technique (BOPT). The sample (149 teeth) was divided into two groups: Seventy four teeth restored with crowns, and 75 teeth supporting fixed partial dentures (FPD). Restorations were fabricated with zirconium oxide cores and ceramic coverings. Patients attended regular annual check-ups when probe depth, presence of inflammation with bleeding on probing, presence of plaque, gingival thickness, marginal stability, biological or mechanical complications, and the patient's level of satisfaction were registered over a 4-year follow-up. RESULTS: After the 4-year follow-up, 2.1% of teeth underwent increases in probing depth; 12% of the sample presented inflammation and bleeding on probing; 20% of the restored teeth presented plaque; gingival thickening increased a 32.5%; 98.6% of teeth presented marginal stability; the restoration survival rate was 96.6%, with 2% of biological complications and 1.4% of mechanical complications. General satisfaction score was 80.73. CONCLUSIONS: Restorations placed on teeth prepared using BOPT present good periodontal behavior, increase of gingival thickening, and marginal stability over a 4-year follow-up. High survival rates after 4 years show that the technique produces predictable outcomes. CLINICAL SIGNIFICANCE: The BOPT technique is a good treatment option in cases where replacement of an old restoration is required; presenting good periodontal behavior, gingival thickening, and marginal stability.

Influence of Biologically Oriented Preparation Technique on Peri-Implant Tissues; Prospective Randomized Clinical Trial with Three-Year Follow-Up. Part I: Hard Tissues.

PURPOSE: The objective of this prospective randomized clinical trial (RCT) was to analyze and compare the clinical behavior of three types of prosthesis supported by single implants in the posterior region after three years functional loading. MATERIALS AND METHODS: Seventy-five implants were divided into three groups according to the type of prosthetic restoration: screw-retained crown (Group GS); cemented crown without finishing line (biologically oriented preparation technique) (Group GBOPT); and conventional cemented crown with finishing line (Group GCC). The clinical behavior of each restoration type was analyzed after 3 years functional loading by analyzing radiographic peri-implant bone loss. RESULTS: GBOPT obtained the least bone loss (p < 0.01) in comparison with GS and GCC. CONCLUSIONS: Bone loss around implants is related to the type of prosthetic restoration it supports, whereby cemented BOPT crowns present less bone loss.

Influence of Biologically Oriented Preparation Technique on Peri-Implant Tissues; Prospective Randomized Clinical Trial with Three-Year Follow-Up. Part II: Soft Tissues.

Purpose: The objective of this prospective randomized clinical trial (RCT) was to analyze and compare the clinical behavior of three types of prosthesis supported by single implants in the posterior region after three years of functional loading. Materials and methods: Seventy-five implants were divided into three groups according to the type of prosthetic restoration: screw-retained crown (group GS); cemented crown without finishing line (biologically oriented preparation technique) (group GBOPT); and conventional cemented crown with finishing line (group GCC). After three years in function, clinical parameters (presence of keratinized mucosa, probing depths, bleeding on probing, and radiographic bone loss) were compared between the three experimental groups. The possible correlation between soft tissue clinical parameters and bone loss was also analyzed. Results: Statistical analysis found significant differences in clinical parameters between the different types of crown, with the cemented restoration without finishing line (BOPT) presenting fewer complications and better peri-implant health outcomes including: significantly different KMW data (mm), with significant differences between groups GBOPT and GCC (p < 0.001, Kruskal-Wallis test), with GBOPT obtaining larger quantities of keratinized mucosa (KM); statistically significant differences in probing depth (PD) values between groups GBOPT and GCC (p = 0.010, Kruskal-Wallis test); significant differences in bleeding on probing (BOP) between groups GBOPT and GCC (p = 0.018, Chi2 test) in favor of GBOPT. Conclusions: Soft tissue behavior around implants is related to the type of prosthetic restoration used, with cemented prostheses with BOPT presenting better peri-implant soft tissue behavior.

Soft-Tissue Enhancement Combined With Biologically Oriented Preparation Technique to Correct Volumetric Bone Defects: A Clinical Case Report.

The aim of the present case report was to illustrate how to obtain an ideal alveolar ridge contour by means of peri-implant soft-tissue management combined with the prosthetic approach of the biologically oriented preparation technique (BOPT). A patient presenting a moderate vertical and horizontal bone loss in the posterior maxilla was treated with sinus floor elevation and simultaneous implant placement. During the reentry procedure, the horizontal defect was corrected with an apically repositioned flap combined with a connective tissue graft. To increase the volume of the interimplant papillae, a pedunculated flap originating from the primary flap was turned within the interimplant space. BOPT one-time abutments have been employed to maximize the space available for the papilla-like tissues. A focused and combined surgical and prosthetic procedure has permitted enhancement of both peri-implant esthetics and function without the need for further invasive and costly bone regeneration techniques.