Communicating facial plane information to the dental laboratory: Introducing the Facial Plane Relator device
J Prosthetic Dent 2001 |Joseph R. Greenberg, DMD, FAGD(a) and Phillip P. Ho, DMD (b)
School of Dental Medicine, University of Pennsylvania, Philadelphia, PA.
The ability of the restorative dentist to communicate the location and orientation of the patient’s pertinent facial landmarks to the dental laboratory technician has great bearing on the esthetic success of final anterior dental restorations. This article describes a new device designed to facilitate this process. (J Prosthetic Dent 2001;86:173-6.)The importance of incorporating facial considerations into the diagnosis and treatment planning of successful esthetic restorative dentistry has been explained in the dental literature.1-3 The inadequacies of using functionally oriented dental articulators and face-bows to record and transfer esthetic facial landmarks to the dental laboratory recently have been summarized by Chiche and Aoshima.4 Some articulator and face-bow systems can be very expensive, complicated, and difficult to understand, which leads to frustration and nonuse. An inexpensive alternative may not provide enough precision to properly restore the patient’s dentition.Effective records should be made at both the diagnostic and the restorative phases of dental treatment; the easier and more precisely this can be performed, the more frequently it will be performed.5 The Facial Plane Relator (Ho Dental Products, Santa Barbara, Calif.) was developed to supplement, not replace, dental articulators or other face-bow devices. The clinician is encouraged to use any and all methods that clarify and complete communication to the dental laboratory. Three specific facial landmarks (the facial midline [FM], facial vertical axis [FV], and facial horizontal axis [FH]) and their dental counterparts (the dental midline [DM], dental vertical axis [DV], and dental horizontal axis [DH]) are the focus of this article and the new device described. We use these terms in dental esthetic examinations, diagnosis, and treatment planning. They are presented here to facilitate the descriptive use of the Facial Plane Relator. The purpose of the Facial Plane Relator is to give the dentist a relatively quick, simple method to transfer FM, FV, and FH locations to the dental laboratory technician before the fabrication of the dental restoration begins. The FM can be found by studying the patient’s entire face in frontal view and bisecting that outline shape. The FV is an imaginary plumb line running through the facial midline and crossing the facial horizontal at a 90-degree angle. The FH is also derived from facial outline examination; it frequently coincides with the horizontal plane of the patient’s eyes. In a symmetrical face, FH and the horizontal plane of the lower lip are parallel, but most faces are not so symmetrical. For example, assume that the 2 maxillary central incisors are located at FM but that their alignment is askew with FV. According to the previously defined terminology, DM and FM would be equal, but DV would deviate from FV. The following clinical report demonstrates the use of the Facial Plane Relator. A 33-year-old white woman presented for esthetic restorative dentistry with the chief complaint of rough, discolored porcelain veneers on her 4 maxillary incisors (Fig. 1). She stated that the teeth had shifted in position and that she no longer felt comfortable or confident with her smile appearance (Fig. 2). Clinical examination revealed various facial bilateral asymmetries (especially eyes and lips) and DV and DH divergent from FV and FH, respectively. A diagnostic face-bow (Hanau Springbow, Teledyne, Ft. Collins, Colo.) showed a horizontal discrepancy between the patient’s interpupillary line and her intercondylar axis (Fig. 3). Without supplemental information, a final restoration guided by this face-bow would have possessed an incisal plane unattractively canted to the patient’s facial symmetry. A Facial Plane Relator was used to capture facial landmark positions and transfer them to the dental laboratory according to the following procedure. Read the full article/refer to fig. 1 – 3: