## 1 Introduction  
Dental aesthetics is one of the primary goals in oral rehabilitation, having a positive effect on the self-esteem and psychosocial wellbeing of patients [1, 2]. In modern dentistry, esthetic outcomes have become increasingly critical for patient satisfaction, which comprises adequate size, shape, color, biotype, gingival zenith, smile line, minimized negative space, axial inclination graduation, incisal embrasure gradation, and gingival frame contour [2, 3]. Several guidelines are introduced to achieve an organizational balance between the aesthetic harmony of the face with the dentofacial structures. These guidelinesform the base of aesthetic knowledge and are widely followed by aesthetic and restorative practitioners worldwide [3; 4; 5; 6; 7; 8; 9; 10]. One of the widely accepted classic esthetic principles is the golden proportion (GP) (1.618:1.0), as proposed by [PERSON] and applied to esthetic dentistry by [PERSON] in 1978 [11]. It was proposed that the golden proportion existed between the dimensions of the central incisor (CI), lateral incisor (LI), and the canine (Ca), as well as within the dimensions of a smiling face, and should be applied to the arrangement of anterior teeth in their esthetic rejuvenation [8; 11]. Later, the golden proportion in dentistry was also advocated by other authors [12; 13]. On the contrary, [PERSON] in 1993 denied the existence of golden proportions in the average natural dentition [14]. He argued that the tooth dimensions vary greatly by race and gender, therefore the golden proportion cannot be applied to the relationship of maxillary anterior teeth [14]. [PERSON] et al. shared similar thoughts as they proposed that use of the golden proportion is theoretical, and its application is challenging in esthetic dentistry [15]. Furthermore, in a study by [PERSON] et al., it was suggested that GP was preferred only when the patient had long teeth [3]. Moreover, [PERSON] et al., proposed that a range of anterior teeth proportions should be considered to determine dental attractiveness rather than a single value despite finding GP in 63% of the Pakistani population using the Phi dental grid [16]. Multiple authors have proposed an altered version of GP in dentistry and introduced their own set of guidelines for anterior esthetic rehabilitation [4; 5; 6]. Studies have suggested that gender, ethnicity, and various genetic and environmental factors are associated with different tooth proportions. Genetic factors can affect the calcification of teeth, the shape of a coronal structure, and the composition of minerals in the process of growth and development of teeth, whereas environmental factors such as diet, nutrition, radiation, and chemicals also affect the mesiodistal width of teeth [9; 10; 17; 18; 19; 20]. Nevertheless, ethnicity is suggested to have a greater influence on tooth proportions than gender [21; 22; 23; 24]. However, it is recommended that the golden principle can be applied if the percentages are adjusted with variations in the ethnicity of the population [21; 25]. In a study by [PERSON] et al. [26], a golden proportion was found to exist between the apparent widths of maxillary anterior teeth for LI/CI (lateral incisor/central incisor) in both Kurdish and Arab populations for men and women, but not for Ca/LI (canine/lateral incisor). However, the proportions among Iraqi Arabs and Kurds were 1.59:1:0.73 and 1.62:1:0.69, respectively. By contrast, in a study by [PERSON] et al., no significant difference in the comparison among the ethnic groups for the golden proportion was found [23]. These outcomes necessitate the evaluation of anterior dentition among various populations or ethnic groups. Nevertheless, different approaches have been developed for conducting systematic reviews on a broader range of issues. This article specifically targeted the presence of GP in different ethnicities and races around the globe. In addition, it aimed to find out the proportions that are present regionally, which was never taken into consideration previously.