Koubi, Stefen

Although it is generally accepted that a prosthetic restoration must take into account the gingiva, smile, and patient’s face, it is often difficult to determine precisely what facial references must be considered. The purpose of this study was to determine the correct vertical and horizontal facial reference planes in esthetic prosthetic treatment. Using photographic analysis of 160 individuals, the different facial reference planes (interpupillary, intermeatic, intercommissural, and incisal edge lines; facial midline; and Camper and Frankfort planes) were compared to the ideal prosthetic reconstruction axis. Additional measurements, including the human eye’s ability to perceive parallelism, were recorded. Most participants (64%) exhibited facial asymmetry. Asymmetry was horizontal (difference between widths of the right and left sides; 52.4%), vertical (difference between heights of the right and left sides; 6.9%), or mixed (4.7%). The interpupillary line is the main horizontal reference in 88.4% of situations, with the intercommissural line the second most important. In the profile view, the horizontal plane was on average 6.5 degrees above the Camper plane and 9 degrees below the Frankfort plane. The human eye’s ability to perceive parallelism between two lines was found to be limited to differences of approximately 1 degree. During anterior tooth reconstruction, it is necessary to take into account the right horizontal and vertical esthetic references. Knowledge of the biometric facial parameters in natural dentition is necessary to define the right reconstruction axes based on the facial symmetry or asymmetry.

Treatment of tooth wear has increased over the last two decades. However, the treatments involved have not been satisfactory to most patients, nor have they achieved the expected goal on some worn teeth. New approaches have emerged to reconstruct full arches in a minimally invasive way that take advantage of developments in the field of adhesive dentistry. These new concepts constitute a revolution in dentistry and their application requires adapted techniques and training. The purpose of this article is to suggest a precise and reproducible method that simplifies the treatment of worn dentition. A wax-up and a mock-up are primarily used to design the esthetic outcome and then used as a guide for the preparation of anterior teeth or the occlusal surfaces of posterior teeth. This not only provides the exact new vertical dimension of occlusion but serves as a guide for precisely controlling occlusal preparation simultaneously with buccal preparation. The classical cavity design for a partial bonded restoration on posterior worn dentition is also reviewed. The authors believe that during the preparation of the occlusal surfaces of the posterior teeth surfaces, the marginal ridges must be preserved to reduce the biologic cost and mechanical stress leading to fracture. A new type of thin and reduced restoration called tabletop is presented.