Dr. Maxime Jaisson
DDS
• Former AHU University of Reims Master in Biomechanics University Diploma in applied facial prosthesis Doctorate in Odontological Sciences Specialized in digital dentistry and especially functional occlusion & TMJ disorders and Implantology.
• Co-founder of MODJAW, holds a predominant role in research and development in the company and still works in a clinic half of the week
• His work in the field of biomechanics as well as the digital maxillofacial prosthesis allowed him to complete his second doctorate in science in 2012
Prof. Marion Paris, Dr. Ouassim Salmi
abstract
abstract
In the case of full-mouth rehabilitation, the practitioner faces many challenges and must master crucial steps such as evaluating the patient and their needs as well as offering an adapted treatment.
How can digital tools help the practitioner in these challenges, and how can they transfer all the digital data to the dental technician to work efficiently without losing information? This clinical case illustrates how digital tools, especially MODJAW™ Tech in Motion™, allow the practitioner to work efficiently in a digital workflow for the benefit of the patient.
introduction
introduction
Digital dentistry is accelerating with the use and improvement of computer-aided design and computer-aided manufacturing (CAD/CAM) in daily dental practice. In the case of full-mouth rehabilitation, many techniques and associated therapies are necessary, making it a real challenge for both the practitioner and the dental technician. These treatments require the establishment of a prosthetic project that will serve as a guide from the implant surgery to the final prosthesis.
The main objective of full-mouth rehabilitation is to restore the dentition by establishing new occlusal architecture and forms at a correct vertical dimension while maintaining the health and harmony of the entire stomatognathic system. From this perspective, the MODJAW™️ Tech in Motion™️ device completes the digital workflow by recording the functional envelope of the patient and helping in the predictability of a treatment plan, especially in the case of immediate loading. It helps to overcome three main challenges encountered in full rehabilitation. The first challenge is to validate a therapeutic mandibular position and transfer it to the laboratory. The second challenge is to respect the occlusal and aesthetic planes. The design of the occlusal anatomy respecting the patient’s specific movements and envelope of function (functional area) can be seen as the third challenge.
An extraction-immediate implant placement situation will be used here to support the application of these new digital tools. The consultation is driven by the wish to regain a harmonious and pleasant smile, as well as masticatory efficiency (Fig. 1A-C).
“Minimally invasive techniques preserve surrounding tissues, promoting faster healing, and real-time feedback allows for adjustments to optimise implant stability.”
the case
the case
MODJAW™️ Tech in Motion™ is a class 1 medical device composed of a hardware and a software (Fig. 2).
THE HARDWARE
This is based on the combination of 3D technology (3D models from intraoral scanners) and motion-capture techniques.
A set of minimally invasive sensors are placed on the patient’s face without interfering with the function. A high-precision, high-frequency (120 Hz) infrared optical camera records the patient’s movements and applies them to their intra-oral scans (Fig. 3). For the first time, we can see what is
happening in the patient’s mouth.
THE SOFTWARE
This is designed like an application to optimise the user experience (Fig. 4). The practitioner can manipulate the 3D models using the computer’s touch screen. The acquisition interface, shown in the figure below, is divided into three main parts.
- On the left are all the features to interact with the 3D models of the patient. The features are divided into three modules: ACCESS, ADVANCED and AESTHETIC.
- On the right are the trajectories of three anatomical points (right condyle, left condyle and sub-nasal
point) in the three planes of space. - In the middle are the recorded movements and the possibility to replay and share them after the departure of the patient.
CASE PRESENTATION: THE DIGITAL DYNAMIC TWIN CREATION
CASE PRESENTATION: THE DIGITAL DYNAMIC TWIN CREATION
Digital twins are digital prototypes or replicas of humans. The real-time jaw motion of the patient adds a layer of dynamic information essential to offer personalised treatment.
The collection of the data starts by taking the intra-oral scans to obtain the 3D models of the actual situation of the maxilla and mandible in a static occlusion (maximum intercuspation; MIP). In addition, 2D photographs and face scans capture extraoral and intraoral information for documentation and education and act as a reference for before and after treatment comparisons (Fig. 5).
A cone-beam computed tomography (CBCT) is performed to give 3D accessibility to craniofacial structures for the examination and treatment initiation (Fig. 6). The benefits of a CBCT in oral and maxillofacial surgery include a diagnosis of bone pathology and developmental anomalies. In implantology, a CBCT permits the area surrounding the future implant to be investigated, along with an evaluation of the height, width and quality of the alveolar bone and awareness of the surrounding anatomical structures.
All these data are collected and imported into the MODJAW™️ software to record the mandibular kinematics of the patient and to get closer to creating a dynamic digital twin (Fig. 7).
AESTHETIC EVALUATION
AESTHETIC EVALUATION
Numerous software programs (e.g. DSD, Smilecloud, SmileFy) are available on the market and provide an aesthetic preview of the prosthetic project to communicate with the patient and help with the process of accepting the proposed therapy. The aesthetic evaluation and planning in this case were made on the Smilecloud platform (Smilecloud, Romania). This offers adaptative libraries out of hundreds of possible designs. The choice is made according to parameters such as the smile line, the position of the lips, the smile and the bipupilar line (Fig. 8).
Once the aesthetic evaluation is done and validated, the chosen library is exported as a 3D model to the laboratory (Fig. 9).
functional EVALUATION
functional EVALUATION
The following records were registered with MODJAW™ Tech in Motion™:
- Open/close
- Protrusion
- Left and right laterotrusion
- Centric relation
- Speech
- Chewing
After the first step of recording is done, a dynamic evaluation is conducted using the MODJAW™️ software. This helps to identify two pieces of information: the mandibular position and the functional envelope of the patient can be preserved.
The mandibular position was evaluated by recording the centric relation (CR). The patient was guided in CR using the bi-manual guided Dawson technique to record a small amplitude of open/close movement so that the condyles remained in the pure rotation (Fig. 10).
The trajectories of the inter-incisal point in the frontal and sagittal planes and the left and right condyles in the sagittal plane showed a reproducible CR coinciding with the MIP position. The second evaluation was to check the functional envelope of the patient by looking at the border limit movements (open/close, protrusion and laterotrusion) and chewing pattern. The chewing showed a well guided by the teeth in place, along with a sharp and symmetric chewing pattern on the left and right condyle trajectories (Fig 11).
It was thus decided to keep the current mandibular position and functional
envelope of the patient for the prosthetic design. To do that in a digital workflow, all the static and dynamic patient data were exported from MODJAW™️ as standard files and imported into Exocad (Exocad GmbH, Germany).
TREATMENT PLANNING: PROSTHETIC AND IMPLANT PLANIFICATION
TREATMENT PLANNING: PROSTHETIC AND IMPLANT PLANIFICATION
A motion dataset provides the dental technician with valuable patient information to help the design:
- A mandibular position in the three planes of space.
- An occlusal plane respecting the functional curves of Spee and Wilson.
- Border limit movements to adjust the anterior guidance according to the protrusion and laterotrusion recorded.
- Masticatory movements to adjust the cusps of the posterior reconstruction.
With the collection of this information, a prosthetic design according to the chosen occlusal concept was achieved. The prosthetic project is called the 4D wax-up because of the use of dynamic movement in the design process (Fig. 12A, B).
Once this 4D wax-up has been created and validated, it becomes the reference that will guide each step of the implant planning. Thanks to the superimposition of the 4D wax-up on the CBCT in exoplan, the implants are ideally positioned in virtual space (Fig. 13A, B).
While the implant placement is planned, a virtual extraction of some teeth on the initial model allows for designing several guides. For each arch, two guides are created. The first is with mixed mucosal and dental support. The idea is to keep the necessary teeth to maintain the guide and place the first implants because dental and mucosal support offers more precision than mucosal support (possible mobility). A second guide is designed on a full extracted model to allow the surgeon total access to the last implant site.
By exporting the 4D wax-up and the position of the implants, the dental technician has the necessary information to create the temporary prosthesis, including aesthetic and functional recommendations to best guide the healing process. The surgeon receives the surgical protocol from the planning, the surgical guide and finished patient’s prosthesis ready to be screwed in.
SURGICAL PHASE & IMMEDIATE LOADING
SURGICAL PHASE & IMMEDIATE LOADING
After anaesthesia, the first teeth are removed. The first guide is used to place the first guided implants in the mandible and maxilla. The residual teeth are then removed, and the second guide is fixed on the implants already in place to continue the placement of the other implants.
For the maxilla, a bone reconstruction was not planned due to the patient. The possibility remained to manage it with osteotomy and crestal access, according to the Summers technique. Sleeves of the surgical guide were used to lead the osteomes on sites 16 and 26 (Figs 14, 15).
After all implants are placed, the variobase and temporary abutments are screwed. We anticipated the prosthesis, which was already milled on the day of surgery. On the maxilla, a support on the palate allowed us to stabilise the prosthesis and connect
it in the right situation. We then injected composite to solidarise on the temporary abutments. For the mandible, the prosthesis was solidarised in occlusion. Everything was then unscrewed again and polished, and the occlusion was controlled (Fig. 16A,B).
“With new digital tools, the dentist can evaluate their patient and collect all their data, static and dynamic. Additionally, they can delegate part of the work to the lab by fully virtualizing the patient”
discussion
discussion
In this type of situation, multiple parameters need to be mastered: bone management, aesthetic evaluation, functional evaluation and psychology.
With new digital tools, the dentist can evaluate their patient and collect all their data, static and dynamic. Additionally, they can delegate part of the work to the lab by fully virtualising the patient and sharing this with the dental technician.
This clinical case highlights how the practitioner can:
- obtain a comprehensive idea of the initial situation on both the aesthetic
and the functional sides - understand the compensation mechanism of occlusion and the impact on mandibular position and movements.
Once the initial evaluation is done, jaw-motion records allow the conservation of the functional initial situation in the prosthetic project. Motion data is very valuable in a situation of immediate loading because jaw motion is partially driven by proprioception, which programmes muscular contraction and is in the muscle memory.
After the surgery, mandibular movement will be only driven by muscular exteroception recorded in the initial situation. Thus, when the designed prosthetic including the initial functional movement is placed, the entire stomatognathic system will not encounter any obstacle. This integration will be smoother.
“The new tools in digital dentistry redefine traditional protocols [..]. Managing the dynamic occlusion of implant restorations in a totally digital workflow is a reality with MODJAW™️ Tech in Motion.”
conclusion
conclusion
The new tools in digital dentistry redefine traditional protocols: they keep improving the predictability and quality of treatments while simplifying the processes.
Managing the dynamic occlusion of implant restorations in a totally digital workflow is a reality with MODJAW™️ Tech in Motion™. The practitioner can evaluate the mandibular position and the dynamic motion of the patient and integrate a new set of data in the prosthetic project to create an ideal static and dynamic occlusion.
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