## 1 Introduction  
In prosthodontics, the evaluation and determination of the correct vertical dimension of the maxillofacial complex and the determination of a valid occlusal plane are two factors and indispensable characteristics for prosthetic success. They contribute to the physical, psychological and social health of the patient, as they are essential for chewing, swallowing, phonation, tissue health, aesthetics and individual personality.  
Prosthetists usually divide the patient profile into three equal parts in order to evaluate the vertical dimension. The vertical relation, called the vertical dimension, is a convenient term used in referring to the nose and chin relations which are affected by the distance between the jaws [1].  
Specifically, the Glossary of Prosthodontic Term defines the rest position as \"the postural relation of the mandible to the maxillae when the patient is resting comfortably in the upright position and the condyles are in a neutral unstrained position in the glenoid fossae\" [2]. Therefore, it is influenced by neuromuscular, dental (presence or absence of dental elements) and psychological factors. In fact, the rest position may be assumed voluntarily and is constantly assumed subconsciously [1].  
On the other hand, the occlusion vertical dimension is defined \"the length of the face when the teeth (oclusal rims, central-bearing point, or any other stop) are in contact and the mandible is in centric relation or the teeth are in centric relation\" [3].  
Another determining prosthetic factor is the construction of a correct occlusal plane.  
On cephalometric radiography, the occlusal plane (OP) is a two-dimensional representation of a three-dimensional entity. The original occlusal plane (OOP), as defined by [PERSON], is a line connecting the point bisecting the first molar cusp height and the point bisecting the incisal overbite [4]. While, the functional occlusal plane (FOP) is obtained by connecting the intercuspation of first premolars and first molars [5,6].  
[PERSON] recognized that the position of both lower and upper incisors is influenced by normal and abnormal functions of the lips and the tongue. For this reason, he suggests using the buccal occlusal plane that he defines the true buccal occlusal plane (TBDP). It is a line through the bisection of the buccal cusps of premolars and first molars or through the deciduous buccal occlusion [7].  
From the prosthetics functional point of view, the occlusal table is a milling surface, strategically placed so that the tongue on the lingual side and the buccinator muscle on the buccal side are able to position the food bolus onto it and hold it there while mastication takes place. Faulty orientation of the occlusal plane in fixed or removable prostheses jeopardizes this interaction between the tongue and buccinator muscle and results at one extreme in food collection in the sulcus, and at the other extreme in biting the cheek or tongue [8].  
There is not a universally accepted method for the determination of the occlusal plane and vertical dimension in edentulous patients; there are many factors to consider and the subjectivity and variability of the patients' characteristics and dental and skeletal patterns takes over. So when a clinician has to select the best method to use, the criteria to be considered are accuracy and repeatability of the measurement, adaptability of the technique, type and complexity of the equipment needed and the time required to plan and obtain the measurements [9,10].  
It is also important to underline that the final objective of an oral rehabilitation is the stability of occlusion [11] and, consequently, the equilibrium of the kinetic chain of the body [12, 13, 14].  
The aim of our study is to demonstrate the efficacy of cephalometry and golden proportions applied to the face in planning prosthetic treatment in totally edentulous patients.