This paper describes a method for designing occlusal contact areas prior to crown fabrication.

Keywords: Occlusion, Contact, Intensity, Design.

An occlusal contact area varies in size, shape and intensity (1). The surface area displays a roughness associated with the opposing contact surface.  Contacts do more than contact. They can rub and abrade their counterparts as well as wreak havoc with a dentition (2). Where does a working occlusion function? Is it in a retruded position (CR), a central position (CO), or in between? (3). It is of interest to make a bite profile and overlay it on an actual working model. (Figure 1). One can study the contact areas along with their intensities and plan the anatomy of the contact areas to be replaced. This gives the dental laboratory a guide for restoring complex occlusal anatomy. Artificial Intelligence programs can record and design the contacts for the technician (4). Upon insertion of a restoration, areas of contact can be adjusted to fit into the working occlusion. It is the concept of placing a restoration into an established environment rather than inserting a new restoration into a worn dentition. (Figure 2) Using the surrounding occlusal contacts for reference one can design a new contact area that fits and adapts. (Figure 3) The rhythm of the functioning occlusion will not be disrupted (5). The contact areas work together. Most important is the design of the contact areas. If the contact areas do not fit at the time of cementation, then adjusting them may be of little value. The occlusal contact areas must be established prior to fabrication. Successful adjustments may then be made upon insertion. It is best to plan and build rather than build without a plan.

We use a triple tray and a non- set reusable silicone impression material for impressions (6). The flow properties of the silicone allow us to make functionally generated recordings if prescribed. Impressions take less than a minute. The impression is immediately processed. It is Illuminated on a light box and a photograph is taken by a camera six inches above the light box. The information is analyzed using image analysis (image J). The resultant black and white image is converted to color and the information is read from the accompanying computer screen. Profiles of the closed contact positions are digitized and stored (7). Occlusal contact areas are identified and design and treatment plans established. Planning is essential for success.

1. Occlusal contact intensity. pubmed.ncbi.nim.nih.gov
2. Accuracy and precision of occlusion. pubmed.ncbi.nim.nih.gov
3. Influence of static and dynamic occlusion. pubmed.ncbi.nim.nih.gov
4. Anatomy, Occlusal Contact Relations and Mandibular Movements https.//www.anatomy standard.com
5. Rhythm of The Rain. Cascades, 1962.
6. Millstein PI., Merrill EW. Occlusal Contact Recordings in Static and Functional Occlusion: Description of an Observational Method. Journal of Dentistry and Oral Implants; Vol.2, 4:10-13, 2022
7. Millstein Pl, Sabrosa CE, Florencio S, Geber K. Consistency and Repeatability of Digitized Occlusal Records. URRD, 2020;3(2): 24-29.