Dr Preeti Tiwari, Dr Saumya Sharma, Dr Sanjeev Singh, Dr Gulab.C. Baid, Dr Vivek Lath, Dr Priyabrata Jena
3rd year PG student,
Professor, Head of Department,
Professor,
Reader,
Senior Lecturer,
Department of Prosthodontics, Crown & Bridge,
MCDRC
ABSTRACT :
Purpose : The objective of our work is to evaluate and investigate the occurrence and prevalence of the much-discussed Golden Proportion provided by Levin on perceived widths of maxillary anterior teeth among the people of Chhattisgarh region with natural and pleasing smiles by measurements made on digital images.
Material and method : The material of this study consists of digital photographs taken of subjects with natural and aesthetic teeth. We took photos of 100 subjects (50 males and 50 females), between 18 and 30 years. Using a computer program, each maxillary tooth was digitally measured. Once the measurements are recorded, theory was applied and data was compared as well as analysed statistically.
Results : The Golden Proportion between the lateral and central incisor occurs in a higher proportion than between the canine and the lateral incisor. The values obtained by analysing the golden proportion differ slightly from those proposed by Levin and Snow.
Conclusions : Results of the current study have shown that golden proportion in Males and Females in Chhattisgarh region was not present between the widths of the maxillary anterior teeth in individuals who had an aesthetic smile.
Keywords : Golden proportion, aesthetic, smile analysis.
Citations : Tiwari P, Sharma S, Singh S, Lath V, Jena P. Evaluation of golden proportion in males and females in chhattisgarh population: a clinical short study. J Prosthodont Dent Mater 2020;1(1& 2): 65-71.
INTRODUCTION
The principles that make up the aesthetics are subtle.1 Methodological analysis has revealed that principles can be applied to evaluate and alter dental aesthetics with predictability.2 Each principle can be considered, recognized, assessed and developed individually in aesthetic management.3 Among the aesthetic principles the proportion can be predicted with a formula that determines the ratio of component from one constituent to next. The Golden Proportion (1.618:1.0) is a mathematically constant ratio that defines the dimensions between the larger and smaller length. This specific relation is unique, perfect, ideal and desirable. It has been used from studying beauty to design aesthetic restorations.4,5 It is also a valuable tool for evaluation of symmetry, dominance and proportion in the diagnosis of tooth arrangement and aesthetic dental treatment.6 The uncertainty of golden proportion in aesthetic analysis and in smile design intended this study to evaluate the existence and comparison of presence of golden proportion in the population of Chhattisgarh region.
AIM
To investigate and evaluate the existence of the Golden Proportion between the widths of the maxillary anterior teeth among males and females in individuals of Chhattisgarh region having an aesthetic smile with natural permanent dentition with the aid of digital photographs and computer analysis.
MATERIAL AND METHODOLOGY
This study was conducted at Maitri College of Dentistry and Research Centre, Durg, Chhattisgarh. Hundred subjects were taken and were divided into 2 groups Male -50, Female – 50 (mean age 24 years). An inclusion criterion for the study was as follows:
a) Age between 18 and 30 years.
b) Skeletal and Dental Class I relation with well-balanced orthognathic profiles.
c) No crowding, spacing or rotation in anterior teeth.
d) No history of previous orthodontic treatment or anterior restorations.
e) No previous history of trauma to the dentition.
f) Presence of all anterior teeth from canine to canine.
Subjects with any visual abnormalities with hard and soft tissues (crowding, rotations, malformations, fractures, abnormalities, etc) and teeth posterior to canine during natural smiling were excluded. A written, informed consent/ approval were obtained from all subjects and the Institutional Review Board. The subjects were informed that their participation in the survey was completely voluntary. A frontal photograph was taken of each individual with an aesthetic smile by Digital camera (SONY Cyber-shot DSC-W810, 20.1 mp) in natural head position. The subject was instructed to sit in an upright and comfortable position.
Lighting and staging were kept constant. The camera was positioned and adjusted so as to obtain a sharp image of the face, from the tip of the nose to the tip of the chin. The distance between the camera and the subject was fixed at a working distance of 60 cm. The camera was stabilized with the help of a tripod, at this fixed distance. The photos were clicked while patient was smiling with the head in the natural position, so that the bipupilar line was parallel to the floor.
Figure 1: Operator taking the photograph of volunteer
The photos were transferred to a computer, and software Adobe Photoshop CS5 (photo editing software) was used to perform the necessary measurements. Using the software vertical lines were drawn at the mesio-distal line angles of all the anterior teeth as seen from the frontal view. We measured the number of pixels per cm, using the zoom function of the program, so that we could measure the apparent mesio-distal width more accurately. For each patient we measured the width of each of the 6 crowns: from canine on the right side (r) to the one on the left side(l): Canine(right) [13], Lateral Incisor (right) [12], Central Incisor (right) [11], Central Incisor (left) [21], Lateral Incisor (left) [22], Canine (left) [23]. The distance between these lines was measured and used to calculate the Golden Proportion for both sides by one individual. After obtaining the results, the calculations were performed corresponding to theories (golden ratio and golden percentage). The resulting data was analysed with the Microsoft Excel and SPSS 17 programs. For processing the data, the paired samples T test was used to analyse the differences in the golden number between the left and right side for each subject’s anterior teeth.
RESULTS
The existence of the Golden Proportion was found to be nearly similar in the left and right side and for both genders. It was found that the difference in Golden Proportion was statistically insignificant between females and males for central incisor/lateral incisor and lateral incisor/canine. For both the genders as well as collectively, a significant difference (p<0.001) from golden proportion was observed for all the three ratios being evaluated.
Statistical analysis: A master file was created with the data, and it was statistically analysed by using the Statistical Package for Social Sciences Software Version 17 (SPSS Inc. Released 2008. Chicago: SPSS Inc). The data was subjected to descriptive analysis for mean, standard deviation, and 95% confidence interval. ‘p’ value less than 0.05 was considered to denote a statistically significant association. For comparison of gender groups independent sample ‘t’-test was performed.
DISCUSSION
Determination of a symmetric or geometrical relation among the anterior teeth is important to achieve an aesthetic result. Existence of statistically reliable results will help to support these existing theories. However, the results of this investigation found no reliable relationships in the average natural dentition. These findings are supported by other investigations.
The Golden Proportion (1.618: 1.0) describes the ratio between the dimensions of a larger and a smaller length. Many previous pieces of research have used this mathematical proportions in dentistry like, Levin in 1978 identified the Golden Proportion between the width of central incisor, lateral incisor and the canine. The golden proportion is founded to be a reliable predictor for determining the width of the maxillary central incisors. In 1993, Preston presented that 17% of his study samples had a golden proportion between the width of the maxillary central and lateral incisors.
On the other hand, other authors found that the golden proportion did not exist between the widths of the maxillary anterior teeth. In this study, relative proportions of central and lateral incisors and canines’ dimensions were recorded according to the golden proportion of 1.618 and no relationship was found. So, the results of the current study concurred with previous studies, that golden proportion did not exist in the study sample of Chhattisgarh region, similar to the results of a study carried out by Wolfart et al., 2006, who reported a width-to-length proportion of 82%.
The rule of the Golden Proportion in dentistry is as follows: The width of the maxillary anterior teeth from the frontal view shows that the visible width of maxillary lateral incisor is 62% of central incisor and the visible width of canine is 62% of lateral incisor. Gillen et al.9 found no correlation existing between tooth dimension and Golden Proportion. Although in their study the values of tooth width were not measured from frontal view as the theory implies –
The Golden percentage was proposed as a simple and objective tool to assess dental aesthetic measures across the midline, and the regressive proportions. The largest study done on the Golden Proportion involved 376 dental students in Jordan. The authors found that average ratio of the maxillary central incisor, the lateral incisor, and the canine was 1.53:1:0.8. The golden section occurs in a higher proportion between the Lateral incisor and Central Incisor, than between the Canine and the Lateral Incisor. The average proportion in our study obtained for canine and lateral incisor is 0.84 in females and 0.81 in males, and for the lateral incisor and central incisor proportion found is 1.51 in females and 1.45 in males, so, in comparison with this study done by Snow SR13 in 1999, we found a greater difference between the proportion of teeth studied and the golden proportion. Therefore, these results do not prove that the Golden Proportion would be the average proportion characteristic for this group of teeth. The variation of views among the current studies and previous studies could be explained due to the lack of the standardization of the protocol used to evaluate the gold proportion. Besides, the differences in racial characteristics might influence such variation.
Many articles have showed that the Golden Proportion was not seen in a majority of observed aesthetic smiles. In the current study the existence of the golden proportion was found to be nearly similar in the left and right side and for both genders. This was also seen in other studies done on golden proportion.16,17 It is clear from the above mentioned result that individual variations are not seen in the Golden Proportion as the width of teeth perceived in maxillary anterior region on both sides are nearly the same unless some malformation or deformity is seen.18,19 Results of the current study have shown that Golden Proportion was not present between the widths of the maxillary anterior teeth in individuals who had an aesthetic smile. This may be mainly due to individual variations in each individual. Genetics also plays a major role in tooth sizes. Change in environment and lifestyle from childhood also may affect the size of the teeth and development of the facial soft tissues. Many studies reported that to produce a satisfactory appearance instead of concentrating on a single ratio, such as the Golden Proportion, other ratios reflecting harmony among tooth lengths should be considered.7,11,20 Further research on this topic is required to obtain clarity on this matter.
CONCLUSION
Results of the current study have shown that golden proportion was not present between the widths of the maxillary anterior teeth in individuals who had an aesthetic smile. This may be mainly due to individual variations in each individual. Genetics also plays a major role in tooth sizes. Esthetics in dentistry cannot be justified mathematically; individuals should not be standardized in the same way as suggested by other authors earlier also.
Although we dentists should follow some fundamental guidelines in esthetic treatment planning, it should be acknowledged that esthetics varies greatly from person-to-person. It is, therefore, important to consider the dento-facial specificities of each individual and the various natural teeth proportions during restoration or replacement of the maxillary anterior teeth. In addition, individual cultural characteristics and perceptions of beauty must be considered.
Change in environment and lifestyle from childhood also may affect the size of the teeth and development of the facial soft tissues. Further research on this topic is required to obtain clarity on this matter.
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