Abstract
Esthetic rehabilitation of patients always involves a number of complexities. These complexities include color, design of the restoration, and soft tissue management. When multiple teeth are restored, there are high demands for optical integration of the restorations into the natural dentition. A second important factor is the soft tissue esthetics, in the area of both implants and natural teeth. One of the techniques for the soft tissue contour management in the area of natural teeth, in particular previously endodontically treated, is the BOPT. This article presents a case of esthetic rehabilitation of a patient with a BOPT crown, an implant-supported crown, a veneer, and a conventional crown in a digital protocol using the eLAB Prime color detection system.
1. Introduction
The anterior teeth present an important role in the overall appearance of a person’s smile. Any defect in these teeth related to color, shape, or alignment can result in a negative impact on the esthetics of the smile. Some of the most common reasons that lead to these defects include carious lesions, old restorations with microleakage, previous endodontic treatment, and trauma [1].
When anterior tooth replacement in the maxillary region is required, it becomes one of the most difficult rehabilitation tasks in dentistry [2]. In oral therapy, functional and esthetic goals cannot be separated [3]. The great challenge for the dentist is to perfectly combine surgery with prosthodontics to obtain an overall satisfactory result. Esthetic complications in implant dentistry have become a significant consideration for patients and practitioners. Soft tissue volume grafting following immediate implant placement in the presence of a thin soft tissue phenotype or simultaneous to surgical peri-implantitis therapy might help to overcome facial mucosa recession [4].
Another way of soft tissue management in the area adjacent to implant teeth is biologically oriented preparation technique (BOPT). It is a protocol in which the emergence of the tooth crown is eliminated above its cementoenamel junction (CEJ) using diamond burs [5]. This makes it possible to create a prosthetic anatomical full coverage crown that will help periodontal tissues to structure themselves and stabilize around the cervical area [6]. Nevertheless, BOPT and chamfer tooth preparation techniques both induce similar qualitative and quantitative changes in supracrestal soft tissue healing compared to nonprepared teeth, but differences between the two techniques were not statistically significant [7].
Currently, visual methods using dental colorants, digital methods using color detection devices, imaging systems, and color matching software are available to identify, analyze, and verify tooth color [8, 9]. Despite these improvements, tooth shade selection has been another challenge in anterior maxillary tooth restoration, especially when the patients require natural color restorations. The esthetic rehabilitation of anterior teeth can be performed with feldspathic ceramic, silicates, zirconia, and hybrid ceramics [10].
This case report presents a case of esthetic rehabilitation of a patient with a BOPT crown, an implant-supported screw-retained crown, a veneer, and a conventional chamfer crown in a digital protocol using the eLAB Prime system.
2. Case Report
2.1. Initial Situation
A female patient, 20 years old, visited the RUDN University dental clinic of the Department of Therapeutic Dentistry due to the trauma to Tooth 11 (Figure 1). The written consent for each of the following procedures was signed. This consent included the publication of photos with the steps of the treatment. The case report was approved by the RUDN University ethics commitment (Protocol No. 12, November 17, 2022).
Figure 1
Dental history including this injury was a second one in this tooth. Teeth 12 and 21 as well as Tooth 11 had been treated endodontically. Tooth 11 was mobile in all directions and lacked sufficient bony support. The radiologic status of Tooth 11 and the remaining teeth was evaluated using Diagnocat artificial intelligence (Diagnocat, Inc., San Francisco, United States) (Figures 2 and 3).
Figure 2 (a)
Figure 2 (b)
Figure 3
Due to the young patient’s severe anxiety, the initial treatment plan included the following steps: extraction and one-stage implantation in the area of Tooth 11 with immediate loading/adhesive temporary crown of the Maryland type and temporary restoration of Teeth 21 and 12. Soft tissue grafting procedures with the recipient area were declined. Written consent was signed for each procedure described below.
2.2. Implant Treatment
A digital planning of the smile including implants is very important and should be prosthetically driven [11]. Prior to implant treatment, an intraoral scan, a CBCT scan (Accuitomo 170, Morita, Japan), and surgical planning in 3Diagnosys software (v. 3.1, 3diemme, Cantù, Italy) were performed. An Astra Tech OsseoSpeed TX 4 × 6-mm implant (DENTSPLY Implants, Molndal, Sweden) was placed using guided surgery with a torque of 15 Ncm. A healing abutment was placed, and an implant was placed. Due to poor primary stability, an adhesive Maryland crown was placed (Figure 4).
Figure 4
2.3. Temporary Direct Restorations
The Implant 11 area required soft tissue augmentation. Unfortunately, the patient refused any surgical procedures. That is why it was chosen to move the emergency profile of Tooth 21, instead of soft tissue augmentation in the implant area to align gingival contours. Four months after implant placement, an intraoral scan was performed to fabricate a digital wax-up and a temporary implant-supported crown (Figure 5). After transferring the mock-up into the oral cavity using Luxatemp Automix Plus A1 (DMG, Germany), Tooth 12 was horizontally prepared for the crown and Tooth 21 in the BOPT concept for apical zenith alignment. The fabricated provisional crowns in the area of Teeth 12 and 21 were fixed with Adhesor Carbofine (Pentron, Czech Republic), and a provisional crown was placed on Implant 11 (Figure 6).
Figure 5
Figure 6
2.4. Milled Temporary Restorations
After 2 weeks of soft tissue stabilization, a intraoral scan was performed on the implant and Teeth 21 and 12. The patient had a wish to restore Tooth 22 with a veneer to improve the esthetics. A gray card and eLAB Prime software were used to determine the shade at this stage (Figure 7). The software was used to select materials and proportions for the crown framework and layering.
Figure 7
Temporary PMMA crowns for Teeth 21 and 12, an implant crown, and a wax-up of Tooth 22 were obtained from the dental laboratory. Initially, the crowns were placed, after which a temporary veneer was fabricated in the area of Tooth 22 by a direct method with the transparent silicone Bisico Regi-trans (Bielefelder Dental Silicone, Bielefeld, Germany) using G-ænial Universal Flo Composite A1 (GC, Tokyo, Japan) (Figure 8).
Figure 8
2.5. Final Restorations
After 2 months, the patient decided to proceed to the final prosthetic restoration. A CEREC Primescan (Dentsply Sirona, Germany) intraoral scan was performed after retraction (Figure 9). The digital scans as STL file were sent to the dental laboratory. The dentist then determined the gingival sulcus, the gingival margin projection on the tooth, and the borders of the restoration (Figure 10). The restorations were fabricated according to the color determined with eLAB Prime.
Figure 9
Figure 10
After fitting the restorations, they were fixed in the following order. Tooth 21 was fixed without a rubber dam (BOPT concept—cubic zirconium dioxide with the porcelain layering). Next, a screw-retained crown was placed on Implant 11 (cubic zirconium dioxide with the porcelain layering). After isolating the operative field with the rubber dam, Restorations 22 (layered lithium disilicate) and 12 (cubic zirconium dioxide with the porcelain layering) were fixed (Figure 11). All restorations were fixed to the teeth using Panavia V5 (Kuraray Co, Ltd, Osaka, Japan). The soft tissue condition after 14 days and 1 year is shown in Figures 12 and 13. The restorations received 1 point—clinically acceptable restorations according to the FDI criteria (esthetic, functional, and biological properties) [12].
Figure 11
Figure 12
Figure 13
3. Discussion
This case report represents different types of restorative design (veneer, BOPT crown, screw-retained implant crown, and conventional crown) according to the indications in one patient. Guided implant placement allows for providing palatal position of the immediately placed implant and straight titanium base [13]. The veneer has been chosen for tooth malposition and smile symmetry correction. Despite the ability to directly place veneers onto enamel, some enamel reduction is required to prevent the formation of an unnatural emergence profile and possible periodontal problems due to overcontouring. Porcelain stained veneers fabricated by computer-aided design and computer-aided manufacturing (CAD/CAM) are also suitable for preparations of 0.3–0.5 mm [14–16]. The gingival margins of the right upper lateral incisor did not require any management; thus, the conventional chamfer crown design was selected.
The soft tissues in upper central incisors presented asymmetry. From a timeline standpoint, these soft tissue grafting procedures may be performed at the time of implant placement, at the time of second-stage implant surgery, or after implant loading. Soft tissue grafting during implant placement may be performed for tissue phenotype modification in anterior cases. It is noteworthy that a recent systematic review did not demonstrate any significant impact for the intervention timing of soft tissue grafting procedures on clinical outcomes [17]. As the patient refused any extra surgery sites and procedures, the use of BOPT for applying ceramic veneers in the anterior regions facilitates periodontal tissue management and symmetry, as an alternative to conventional treatment [18].
Compared with conventional preparation techniques, BOPT is accompanied by greater gingival thickening produced during dental preparation. This reduces the risk of gingival displacement thanks to increased vascularization, regardless of whether the patient presents a thin or thick gingival biotype [5]. The disadvantages of BOPT compared to horizontal tooth preparation are related to its greater complexity. A crown margins must be placed despite the absence of dental landmarks, which carries the risk, especially when the clinician or technician is inexperienced, of uncontrolled penetration into the gingival sulcus. Another disadvantage is related to cementation, as it is impossible to precisely isolate the area, as there is no horizontal preparation boundary to follow, and any excess cement will be difficult to remove [19, 20]. This is the reason why the cementation of Crown 21 was performed without a rubber dam, while it was used for Teeth 22 and 12.
In recent years, the use of AI in dentistry has been increasing and its application has been observed in various dental specialties. Despite this trend, the number of studies investigating the diagnostic accuracy of AI-based instruments in various settings and locations remains relatively limited [21]. Volume measurements performed by humans and by Diagnocat systems were comparable to each other [22]. AI systems based on deep learning methods can be useful for detecting periapical pathosis on CBCT images for clinical application. Also, it presents a good visualization of the pathology in 3D STL mode.
Today, shade definition can be performed with digital cameras on diffusely scattering objects with irregular geometry or complex shape and structure. Otherwise, this task would be a tedious and expensive task to solve with photospectrometers. The eLAB system based on shade quantification may finally pave the way to becoming the practice standard for the objective communication of shade information in dentistry [23]. In this case, it was used before the tooth preparation to evaluate the original tooth shade.
This case report approves that digital workflow for BOPT crown design and preparation is rapidly implementing and optimizing, making it the most realistic option for dental digitalization [24]. However, the limitation of this study is the short follow-up period, though BOPT can provide good periodontal behavior, gingival thickening, and marginal stability for restorations on teeth, with high survival rates after 4 years [25].
4. Conclusions
Digital technologies are becoming more accurate and can be used on the different stages of the treatment. To carry out an esthetic plan, it is important that both the dentist and dental technician collect information using modern technologies. Also, evaluation of the current clinical situation can lead to the right choose of the used materials and methods that will satisfy the patient’s expectations.
Source: https://onlinelibrary.wiley.com/doi/full/10.1155/2024/4439636