Biofunctional Prosthetic System: Integrating Biomechanics and Aesthetics for Enhanced Patient Outcomes

In recent years, various techniques and systems for creating complete dentures have emerged. One notable method is the Biofunctional Prosthetic System (Ivoclar Vivadent Co., hereafter referred to as BPS). The BPS represents a progressive approach to prosthetic dentistry that prioritizes both functionality and aesthetics by emulating natural biomechanics. This brief communication outlines the principles, benefits, and clinical advantages of the BPS system regarding patient comfort, occlusal efficiency, and aesthetics. It encourages wider implementation by examining the components of BPS, its workflow, and its advantages compared to traditional techniques. The BPS streamlines clinical procedures, reduces variability among practitioners, and provides clearer objectives, establishing it as a superior choice for complete denture fabrication.

In prosthetic dentistry, the challenge of restoring function while preserving aesthetics is ongoing. Traditional methods often sacrifice one for the other, resulting in less-than-ideal outcomes. The Biofunctional Prosthetic System (BPS) represents a transformative approach that strives to achieve an optimal balance. By integrating advanced materials and modern digital technologies, BPS enhances the biomechanical performance of dentures, thereby improving masticatory function and delivering a more natural appearance. Additionally, the system takes into account the preservation of oral tissues and the unique anatomical features of each patient, contributing to better long-term results.

Recently, there has been growing concern that an increasing number of dental graduates lack adequate proficiency in complete denture treatment due to insufficient clinical practice opportunities and a reduction in class hours dedicated to this area. Moreover, with the rising incidence of severe jawbone resorption-driven by factors such as implant treatment failures and the longer life expectancy of the elderly-the clinical and educational landscape surrounding complete dentures in India appears quite bleak.

In response to these challenges, several methods and systems for the fabrication of removable dentures have been developed, including the BPS (Biofunctional Prosthetic System). BPS is a patented comprehensive system for denture fabrication created by Ivoclar Vivadent, a company based in the Principality of Liechtenstein. The acronym BPS emphasizes the principle of prosthetic dental treatment that focuses on the functional movements generated by the body.

In comparison to earlier techniques, the BPS system is founded on a clear concept aimed at simplifying clinical procedures to minimize variability among practitioners. The system offers nearly all necessary materials and equipment for denture fabrication, encompassing everything from the impression system to the injection system for artificial teeth and denture base resin.

This paper will explore the benefits of BPS in clinical practice for complete dentures, detailing the clinical steps while highlighting its distinctive concepts.

Components of the Biofunctional Prosthetic System

The Biofunctional Prosthetic System (BPS) incorporates several key components that set it apart from traditional prosthetic systems:

Functional Impression Technique: By utilizing high-quality impression materials, BPS achieves precise recordings of oral tissues, capturing both static and dynamic details to ensure an optimal fit for the prosthesis.

Anatomical Teeth Design: The system features denture teeth designed to replicate natural morphology, providing both aesthetic appeal and functional efficiency in terms of occlusal forces.

Occlusal Concept: BPS employs a balanced occlusal scheme that improves chewing efficiency while minimizing trauma to oral tissues. The arrangement of teeth distributes forces evenly, reducing the risk of premature wear or overloading of the prosthetic base.

Material Selection: The use of high-performance materials, such as nano-hybrid composites, ensures that the prosthesis is not only durable but also capable of withstanding daily functional stresses without sacrificing aesthetics.

Digital Workflow: The system frequently integrates computer-aided design and computer-aided manufacturing (CAD/CAM) technology, enabling accurate design, fit, and production of prostheses. Digital tools ensure precision at every stage, from impression to fabrication.

Benefits of Each Clinical Step in BPS

Let us now outline the clinical steps involved in the Biofunctional Prosthetic System (BPS) and the associated benefits of each step. The general workflow at the chairside for BPS typically involves taking the preliminary impression and simple occlusal registration on the first day, followed by the final impression and occlusal registration using a Gothic arch tracing on the second day. On the third day, the arrangement of artificial teeth is tried, and on the fourth day, the denture is finalized and delivered to the patient. Since both the final impression and occlusal registration can be completed during the second appointment, this reduces the total number of appointments by one. However, in the standard BPS protocol, the position of the anterior teeth is determined based on anatomical averages rather than assessing lip support with wax rims as is done in traditional methods. This often requires adjustments to the position of the anterior teeth during the third appointment. Consequently, we typically conduct a try-in of the anterior teeth on the third day, a try-in of both the anterior and posterior teeth on the fourth day, and then deliver the denture on the fifth day. In essence, the BPS protocol emphasizes completing the process in four steps, which should be viewed as the minimum necessary steps rather than a strict limitation.

Preliminary Impression: On the first day, a preliminary impression and simple occlusal registration are performed. The preliminary impression is taken using the Accu-Dent System, which features a custom tray and impression material. This system has two main advantages: first, the trays come in unique shapes and various sizes; second, it uses two types of impression materials with different flow properties to create a combined impression. After selecting an appropriately sized tray, a syringe injects the high-flow material into areas prone to bubbles, such as the mucobuccal fold, before inserting the tray filled with low-flow body material. This technique minimizes bubbles and improves overall impression accuracy. Furthermore, it has been reported that this method provides a larger impression surface area compared to traditional single-material impressions.

Recording the Range of Motion: While the Accu-Dent system captures a broad surface area, it does not perform border molding, which means there is insufficient information to define the tray's outer contour. To address this, BPS includes a step to record the mucosal range of motion on the impression. This involves observing the alveolar ridge and surrounding mucosa while manually retracting the cheeks and lips to identify the boundary between movable and non-movable tissue. A mucosal pencil is then used to mark this boundary on the impression. Measuring distances from the ridge crest with a probe or similar tool ensures accuracy. This step allows for a comprehensive understanding of the range of motion from the study model, which aids in outlining the custom tray.

Simple Occlusal Registration: Following the preliminary impression, a simple occlusal registration is performed using a specialized tray known as the Centric Tray. The procedure starts with marking the tip of the nose and chin with stickers to measure and establish the desired occlusal vertical dimension. Alginate impression material is applied to the upper and lower surfaces of the Centric Tray, which is then inserted into the patient's mouth and pressed against the lower jaw. The upper lip is retracted, and the tray angle is adjusted to ensure that the frame does not contact the alveolar ridge. The patient is instructed to close their mouth until reaching the predetermined vertical dimension and to swallow to finalize the position while the material sets. This step allows for the study model to be mounted on the articulator during the same appointment, providing a general understanding of the intermaxillary relationship. Additionally, this impression can be used to create a tray for a closed-mouth impression.

Final Impression: The tray for the final impression incorporates a specialized device called the Gnathometer M, which facilitates both the final impression and Gothic arch tracing in succession. The BPS impression technique typically utilizes silicone materials with varying flow properties and is primarily performed with the patient in a closed-mouth position, utilizing the patient’s movements. This is referred to as a closed-mouth impression or functional closed-mouth impression.

After taking the impression, a very low-flow Virtual material is built up around the edges of the tray, which is then inserted into the oral cavity for occlusion. The patient is asked to perform various movements to aid in border molding. Once the material sets, any excess portions are trimmed, and a wash-type impression material, known as Virtual Light Body, is added and inserted while repeating similar movements to capture the wash impression.

Several benefits of using a closed-mouth impression include:

• Reduced Operator Variability: The risk of variation due to the clinician's technique is minimized.
• Functional Border Formation: Utilizing movements such as swallowing helps form the borders without hindering the functional range of motion.
• Functional Sealing: Taking the impression in a state close to the functional use of the denture allows for better sealing of the borders during function.
• Consistent Pressure Application: As occlusion is achieved, the direction of pressure applied to the tray remains constant, making repositioning easier.
• Reliable Contour Formation: Setting an occlusal rim based on the dental arch enhances the reliability of the contour of the impression surface.

Gothic Arch Tracing: After completing the impression, the components of the Gnathometer M are replaced, and the tracing plate and stylus for Gothic arch tracing are attached. The Gothic arch recording is then conducted following standard procedures, allowing for the determination of the desired jaw relationship, which is fixed in place using silicone impression material. This means that Gothic arch registration can be performed on the same day as the impression, and using the impression body as a stable occlusal base enhances the accuracy of recording the intermaxillary relationship.

Artificial Tooth Arrangement and Try-In: As previously mentioned, we often perform try-ins solely for the anterior teeth of the maxilla. This is necessary because adjustments to the position of the anterior teeth are frequently required without evaluating lip support with wax rims during the final impression using the Gnathometer. Following this, the posterior teeth are arranged, and a wax denture try-in is conducted, often in the presence of certified dental technicians who have completed the same educational courses as the dental surgeon. This collaboration facilitates accurate and effective adjustments and communication at the chairside.

Polymerization: Once the wax denture is complete, the focus shifts to polymerizing the denture base. In BPS, a specialized denture base material and polymerization system known as Ivobase is used. Ivobase compensates for polymerization shrinkage, resulting in high precision in fit, strength, and minimal residual monomer. Furthermore, in response to growing aesthetic demands from patients, materials for gingival characterization—adding color to the denture base—are also available.

In summary, BPS allows for the fabrication of dentures tailored to individual patient aesthetic needs using high-quality denture base materials.

Denture Insertion: After the denture is completed, the insertion of the BPS denture occurs. Adjustments made during insertion are similar to those with conventional complete dentures; however, literature indicates that BPS dentures require significantly fewer adjustment appointments after insertion. This suggests that the dentures produced through the BPS method may fit more accurately upon completion.

Advantages of BPS Over Conventional Systems

The Biofunctional Prosthetic System (BPS) offers numerous benefits:

Enhanced Fit and Retention: The accurate recording of a patient’s anatomy, along with advanced impression techniques, guarantees a better fit and retention for dentures.

Improved Masticatory Function: By closely mimicking the natural function of teeth, BPS enhances chewing efficiency, resulting in greater patient satisfaction regarding food processing and dietary habits.

Aesthetic Superiority: BPS prioritizes the use of lifelike dental materials and tooth shapes that closely resemble natural dentition, ensuring high aesthetic value and patient contentment.

Tissue Preservation: This system encourages the preservation of oral tissues by promoting an even distribution of functional forces, thereby preventing pressure spots or irritation that could lead to bone resorption or tissue trauma.

Clinical Application

The Biofunctional Prosthetic System is especially beneficial for patients needing full or partial dentures, particularly those with compromised oral tissues. Its comprehensive approach takes into account the biological, mechanical, and aesthetic needs of the patient, resulting in a more satisfactory outcome.

Case Example

A 65-year-old patient exhibited advanced ridge resorption and experienced challenges in retaining traditional dentures. Utilizing the Biofunctional Prosthetic System (BPS), the dentures were created following a thorough functional impression and occlusal analysis. The patient reported marked improvements in comfort, chewing efficiency, and overall satisfaction, highlighting the effectiveness of the BPS approach.

The Biofunctional Prosthetic System (BPS) is a state-of-the-art solution that overcomes the limitations of traditional prosthetics by integrating biomechanics with aesthetics. Its advanced materials, occlusal concepts, and digital precision facilitate the creation of prostheses that fulfill both functional and aesthetic requirements. As dentistry continues to progress, BPS represents a promising pathway for enhancing patient outcomes in prosthetic treatments.

As previously discussed, the BPS method for denture fabrication offers several benefits at each clinical step. These advantages can be categorized into three main groups: 1) those related to materials and equipment, 2) those pertaining to the techniques used, and 3) those associated with educational effectiveness and collaboration with dental technicians.

Benefits Related to Materials and Equipment

BPS denture production utilizes high-quality materials and equipment provided by a single manufacturer, ranging from alginate impression materials to denture base materials. This ensures consistency in quality and performance throughout the entire process.

Benefits Related to Techniques

The BPS technique, particularly for impression and occlusion recording, is founded on a core principle of progressively increasing accuracy from rough to precise.

Impression Recording: Initially, a preliminary impression is taken using a broad impression area to accurately capture landmarks. This step also involves recording the range of mucosal mobility and fabricating an adequately extensive tray to encompass the necessary non-movable areas of the denture.

Border Molding: By utilizing the patient's movements, suitable borders and sufficient denture base area can be achieved without hindering functional movements.

Occlusion Recording: The process begins with a centric tray for simplified occlusion recording. During the final impression, the impression material is built up within the tray, allowing for occlusion adjustments based on material thickness. Additionally, the impression body itself serves as a stable occlusal base for conducting Gothic arch tracing, resulting in more accurate occlusion recordings.

Benefits Related to Educational Effectiveness and Collaboration with Dental Technicians

As mentioned earlier, BPS requires dental surgeons and technicians to participate in educational courses and certification. This collaborative approach often allows for the technician’s presence during clinical procedures, fostering a mutual understanding of treatment objectives. Such collaboration can help address various issues that a dental surgeon might overlook.

Moreover, the differences in BPS techniques compared to traditional methods prompt many practitioners to ask reflective questions such as, “Why is this technique being used?” and “What distinguishes it from traditional methods?” This critical questioning encourages deeper thinking and a better understanding of the rationale behind the procedures.

In summary, this introduction briefly outlines the BPS method and its benefits. Given the current landscape surrounding complete denture clinical practices and education, the principles underlying BPS are likely among the most essential in contemporary dentistry.