A look at the principles of dental aesthetics

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A look at the principles of dental aesthetics Masters in Advanced General Dental Practice Qualtrough AJE, Burke FJT. A look at dental esthetics.

. Definition of cosmetic/aesthetic dentistry History and research on tooth shape Factors influencing the aesthetics of restoration Different

dentistry and cosmetic dentistry? Aesthetics Glossary of Prosthodontic Terms J.Prosthet.Dent.

1 A look at the principles of dental aesthetics Masters in Advanced General Dental Practice Qualtrough AJE, Burke FJT. A look at dental esthetics. Quintessence Int.1994:25:7-14. What I plan to talk about.. Definition of cosmetic/aesthetic dentistry History and research on tooth shape Factors influencing the aesthetics of restoration Different techniques available The ethics of aesthetic dentistry What is Dental Aesthetics? What is Dental Aesthetics? and, is there a difference between aesthetic Yes! dentistry and cosmetic dentistry? Aesthetics Glossary of Prosthodontic Terms J.Prosthet.Dent.1968, Bader OE. J.Prosthet.Dent.1971:23: The branch of philosophy dealing with beauty, especially the components thereof, such as colour and form The qualities involved in the appearance of a given restoration Aesthetics is a phenomenon of intellect Tastes in beauty are dependent upon existing culture 1

2 Aesthetic: Related to pure beauty rather than to other considerations, artistic or relating to good taste Cosmetic: Serving to beautify the body, esp. the face, having no function other than to beautify Collins Dictionary of the English Language Collins Dictionary of the English Language Cosmetic dentistry Dental procedures carried out, even in the absence of pathology, for the primary purpose of improving the patient s appearance Cosmetic dentistry Dental procedures carried out, even in the absence of pathology, for the primary purpose of improving the patient s appearance Aesthetic dentistry Is carrying out everyday dentistry to a highly aesthetic standard Questions? Do we preserve or repair natural beauty? Can we improve nature? What is beautiful and what is unattractive? And, who decides this? To preserve or obtain beauty is the most important motive to visit a dentist Goldstein & Lancaster, 1986 The clinician must have a thorough knowledge of form and colour, And, communication skills 2

3 but, there are forces on restorations Objective & subjective need for cosmetic dentistry in the Dutch population. Community Dent.Oral Epidemiol.1991:19:61-63 % persons with one or more teeth in need of cosmetic dentistry 2,784 dentate persons, yrs of age Aesthetics of anterior teeth & 1 st premolars Assessed by clinician. Assessed by patient. 3

1991:19:61-63 In almost all age categories, disturbances in shape or colour

(52%). In the first premolars, colour was the most mentioned reason (56%).

the fashion in recent years to use the term cosmetic rather than esthetic.

It would be unfair to the barber and perfumer to filch from them a term

the teeth should be so shaped that correct anatomical relationship can be

4 Objective & subjective need for cosmetic dentistry in the Dutch population. Community Dent.Oral Epidemiol.1991:19:61-63 In almost all age categories, disturbances in shape or colour of the tooth/teeth were the reasons most mentioned for incisors and canines (52%). In the first premolars, colour was the most mentioned reason (56%)...ps 80% of participants in the study were regular attenders It has been the fashion in recent years to use the term cosmetic rather than esthetic. I cannot fall in with this. It would be unfair to the barber and perfumer to filch from them a term that they have made their own J.Leon Williams Dental Cosmos. 1911:LIII;1-26.the teeth should be so shaped that correct anatomical relationship can be secured with them J.Leon Williams Dental Cosmos. 1911:LIII;1-26 The Golden Proportion Levin EI. Dental esthetics and the golden proportion. J.Prosthet.Dent.1978:40:

The Golden Proportion Not! Preston JD The Golden Proportion revisited. J.Esthet.

The Golden Proportion Revisited Preston measured a sample of 58 images

relationship between the maxillary central incisor and maxillary lateral

perceived maxillary lateral incisor and canine widths.

American population, indicated that the width of the average maxillary

5 The Golden Proportion Not! Preston JD The Golden Proportion revisited. J.Esthet.Dent.1993:5: The Golden Proportion Revisited Preston measured a sample of 58 images of maxillary and mandibular teeth of 58 second year dental students and 52 actual casts. The Golden Proportion was not found to be correlated with the relationship between the maxillary central incisor and maxillary lateral incisor, nor was the Golden Proportion found to exist between any perceived maxillary lateral incisor and canine widths. The Preston Proportion: Results, following a survey of the North American population, indicated that the width of the average maxillary lateral incisor was 66% of the width of the average central incisor, & the average canine was 84% of the width of the average lateral incisor Preston JD. The golden proportion revisited. J.Esthet.Dent.1993:5:

The Golden Proportion Revisited Preston pointed out that the problem with the Golden Proportion as applied to teeth is that it measures the apparent, rather than the actual width of the teeth.

The Golden Proportion Revisited Bakhary and co-workers investigated the digital alteration of a female smile to change the proportion of the maxillary lateral incisor teeth in proportion to the

6 The Golden Proportion Revisited Preston pointed out that the problem with the Golden Proportion as applied to teeth is that it measures the apparent, rather than the actual width of the teeth. The Golden Proportion Not! Bakhary SMN, Gill DS, Tredwin CJ, Moles DR. The influence of varying maxillary lateral incisor dimensions on perceived smile aesthetics. Br.Dent.J.2007:203: The Golden Proportion Revisited Bakhary and co-workers investigated the digital alteration of a female smile to change the proportion of the maxillary lateral incisor teeth in proportion to the central incisors, with the images being judged by 87 patients and 30 dentists. The results indicated no evidence that the Golden Proportion should be considered the ideal aesthetic standard when creating space for the replacement of missing maxillary lateral incisors. Other Proportions Ward DH. A study of dentists preferred maxillary tooth width proportions: Comparing the Recurring Esthetic Dental Proportion to other mathematical and naturally occurring proportions. J.Esthet.Restor.Dent.2007:19: Survey of 301 North American dentists attending continuing education courses to determine preferences of anterior tooth width proportions Golden Mean: Width of maxillary central should be 25% of the total frontal width, each lateral should be 15% and each canine 10%. Ward DH. J.Esthet.Dent.2007:19:

7 Recurrent Esthetic Dental (RED) Proportion: Favours variability among individuals and factors the proportion of the tooth, face and body into the calculations RED: The proportion of the successive widths of the maxillary teeth as viewed from the front should remain constant, progressing distally RED: Recommended for normal length teeth with a 78% width/height ratio of the central incisors Results Overall, 57% of dentists preferred the smiles with the 70% RED proportion Dentists preferred the smiles of the naturally occurring maxillary tooth proportions (70%) and the RED proportion (75%) over the golden proportion In smiles with tall teeth, the golden proportion was preferred by 58% of dentists Results Overall, 57% of dentists preferred the smiles with the 70% RED proportion Conclusion Smiles created using the principles of the RED proportion were preferred by a majority of dentists surveyed Not a massive majority!! 7

Other Proportions The dentists indicated no significant difference in preference between the Golden Proportion and the Golden Mean and showed that dentists preferred the smiles of the naturally

Trevor s conclusion There was no real consensus among dentists with regard to smile design!

8 Other Proportions The dentists indicated no significant difference in preference between the Golden Proportion and the Golden Mean and showed that dentists preferred the smiles of the naturally occurring maxillary tooth proportions and the 70% RED proportion over the Golden Proportion. The majority of dentists reported that overall balance was a primary factor. Trevor s conclusion There was no real consensus among dentists with regard to smile design! Other views Impressions made of 69 dentate students in Brazil Anterior teeth measured with digital calipers Other Proportions Goncalves LC, Gomes VL, Lucas BDeL, Monteiro SB. Correlation between the individual and the combined width of the six maxillary anterior teeth. J.Esthet.Restor.Dent.2009:21: In study of tooth width, Goncalves and colleagues made casts of 69 dentate undergraduate students in Brazil, considered to be a heterogeneous population because of its ethnic mix. They measured the individual widths of maxillary anterior teeth using digital callipers, with the results indicating that there was a significant difference between analogous teeth from both sides of the dental arch with the exception of the central incisors. Width of central incisors of females less than males (8.97mm vs 8.53mm) Significant difference between analogous teeth from both sides of the arch, except for the central incisors 8

9 Conclusions Nature is rarely perfectly predictable There is usually substantial variation around the fitted regression line When restoring teeth, symmetry of the central incisors is central to success Other proportions Chu SJ. Range and mean distribution frequency of individual tooth width of the maxillary anterior dentition. Pract.Proced.Aesthetic Dent.2007:19(4): Chu SJ, Okubo S. Range and mean discordance of individual tooth width of the mandibular anterior dentition. Pract.Proced.Aesthetic Dent.2008:20(5)): Chu SJ. A biometric approach to predictable treatment of clinical crown discrepancies. Pract.Proced.Aesthetic Dent.2007:19(7): Chu SJ, Tan JH-P, Stappert CF-J, Tarnow DP. Gingival zenith positions and levels of the maxillary anterior dentition. J.Esthet.Restor.Dent.2009:21: Chu SJ., Hochman MN, Fletcher P. A biometric approach to aesthetic crown lengthening: Part II interdental considerations. Pract.Proced.Aesthetic Dent.2008:20(9)): Other proportions (according to Chu) Practitioners have been hidebound by mathematical principles Use of an innovative esthetic measuring gauge could enable the quantification of tooth size discrepancies and enable the clinician to perform esthetic dentistry predictably (Chu 2007). Introduced this approach to crown lengthening (Chu, Hochman 2008). Other proportions Chu examined 54 casts from patients, measuring the widths of anterior teeth, finding that the central incisors, lateral incisors and canines varied in width from 7mm to 10mm, 5.5mm to 8mm and 6.5mm to 9mm respectively and only 36% of the total population exhibiting the mean tooth width of 8.5mm for central incisor teeth. However, 82% of the patients fell within +/- 0.5mm of the mean values (Chu 2007). For male patients, maxillary anterior teeth ranged from 0.5mm to 1mm wider than for female patients. Other proportions Chu and Tan examined the gingival zenith position at 240 sites in 20 adult patients of mean age 28 years who exhibited no periodontal disease. The results indicated that the gingival zenith position of the lateral incisors relative to the adjacent central incisor and canine teeth was more coronal by circa 1mm (Chu, Tan 2009). Other proportions With regard to the mandibular dentition, Chu and Okobo examined 70 stone casts from 36 male and 34 female patients in a private practice population, finding that mandibular anterior teeth are more consistent in size and variability than maxillary anterior teeth and only the mandibular canine teeth exhibiting a gender difference (Chu & Okobo). These workers added that, while anatomic values of tooth size are well established in the literature, there is a misconception that these absolute numbers are applicable to the majority of patients. 9

10 Anatomic crown/width ratios of worn and unworn maxillary teeth in white subjects Magne, Gallucci and Belser. J.Prosthet.Dent.2003:89: Method: Standardised digital images of 146 extracted human maxillary anterior teeth, length/width ratio calculated for each tooth. Teeth classified as worn and unworn. Anatomic crown/width ratios of worn and unworn maxillary teeth in white subjects Magne, Gallucci and Belser. J.Prosthet.Dent.2003:89: Results: Widths: central incisors ( mm), canines (7.9 to 8.06), laterals ( ). Longest crowns were unworn centrals (11.69mm), unworn canines (10.83), shortest were worn canines (9.9mm). Anatomic crown/width ratios of worn and unworn maxillary teeth in white subjects Magne, Gallucci and Belser. J.Prosthet.Dent.2003:89: Results: Highest W/L ratios were for worn centrals (87%) and worn canines (81%). Lowest W/L ratios were unworn canines and unworn lateral incisors (both 73%). We guessed that anyway! Length to width ratios Length/Width Ratio? Length/Width Ratio?

Width/Length Ratio? Sterrett JD et al. Width/length ratios of normal clinical crowns of the maxillary anterior dentition in man. J.Clin.Periodontol.

(Caucasian) 24 males and 47 females recruited 0.58 0.77 1.0 0.54 0.66 Sterrett JD et al. Width/length ratios of normal clinical crowns of the maxillary anterior dentition in man. J.Clin.Periodontol.

11 Width/Length Ratio? Sterrett JD et al. Width/length ratios of normal clinical crowns of the maxillary anterior dentition in man. J.Clin.Periodontol.1999:26: Subjects > 20yrs recruited Alginate impressions taken Calipers used to measure teeth Gender, ethnicity and height recorded Statistical analysis carried out only on one group (Caucasian) 24 males and 47 females recruited Sterrett JD et al. Width/length ratios of normal clinical crowns of the maxillary anterior dentition in man. J.Clin.Periodontol.1999:26: RESULTS: Mean width/length ratios, standard deviations and range. Gender Central Lateral Canine Sterrett JD et al. Width/length ratios of normal clinical crowns of the maxillary anterior dentition in man. J.Clin.Periodontol.1999:26: CONCLUSIONS: Within male and female Caucasians, the mean width/height ratio of the three maxillary tooth groups is 0.81 Male 0.85 (0.09) 0.76(0.09) 0.77(0.08) (range) Female 0.86 (0.07) 0.79 (0.09) 0.81 (0.07) (range) Width/Length Ratio? Hot off the press! Closest to the research findings!

Stresses that patients are generally less concerned about dental appearance than dentists or technicians.

12 . Recent research confirms 82% width to height ratio as most attractive for central incisors. Recent research confirms 82% width to height ratio as most attractive for central incisors Highlights differences in perception of dental aesthetics between dentists, technicians and patients. Stresses that patients are generally less concerned about dental appearance than dentists or technicians. Suggests 82% is the most attractive width-to-height ratio for normal central incisors for the majority of patients The influence of maxillary central incisor height-towidth ratio on perceived smile aesthetics G. E. Cooper, C. J. Tredwin, N. T. Cooper, A. Petrie & D. S. Gill British Dental Journal 212, (2012) The influence of maxillary central incisor height-towidth ratio on perceived smile aesthetics G. E. Cooper, C. J. Tredwin, N. T. Cooper, A. Petrie & D. S. Gill British Dental Journal 212, (2012) Width to length ratios: There appears to be wide variability, but around 0.80 seems to have the vote Proportions: Is there a consensus view? Not really!!! Proportions: Is there a consensus view? Creation of maxillary central incisors of similar widths is an important criterion. Appearance enhanced if there is symmetry around the midline Gingival zenith position of the lateral incisors relative to the adjacent central incisor and canine teeth is more coronal by circa 1mm Patients prefer horizontal symmetry Symmetry Symmetry is an important factor 12

2006:18:196-205 Method: standardised digital images of 81 dentate Brazilian subjects used to measure facial and oral segments. Casts also made and measured. Spearman Rank Coeff. conducted.

13 Take home message Other than symmetry of the central incisor teeth, there is no real consensus with regard to tooth dimensions. Comparison with facial proportions Correlation between facial elements and the mesiodistal width of the maxillary anterior teeth Gomes et al, J.Esthet.Restor.Dent.2006:18: Method: standardised digital images of 81 dentate Brazilian subjects used to measure facial and oral segments. Casts also made and measured. Spearman Rank Coeff. conducted. Correlation between facial elements and the mesiodistal width of the maxillary anterior teeth Gomes et al, J.Esthet.Restor.Dent.2006:18: Conclusion: Significant correlation between all facial elements and the combined mesiodistal width of the teeth. Does dental aesthetics affect confidence? 13

Does dental aesthetics affect confidence? YES!! and what are patients preferences?

governmental restrictions and amalgam-usage survey results. J.Dent.2004:32:343-350.

14 Does dental aesthetics affect confidence? YES!! and what are patients preferences? Patient preference Burke F.J.T. Patient acceptance of posterior composite restorations. Dent. Update. 1989:16: Patient desire for aesthetic restorations is high Posterior Aesthetics are becoming more important Burke F.J.T. Amalgam to tooth-coloured materials implications for clinical practice and dental education: governmental restrictions and amalgam-usage survey results. J.Dent.2004:32: Prevalence of self-assessed tooth discolouration in the United Kingdom. Alkhatib MN, Holt R, Bedi R. J.Dent.2004:32: Methods: National questionnaire interview completed for 3384 of 5504 subjects Effect of socio-economic variables explored 14

Prevalence of self-assessed tooth discolouration in the United Kingdom.

Results: 75% of those who assessed their tooth colour as normal were

discoloured teeth than males Prevalence of discolouration appeared to

themselves as having discoloured teeth Results: Half of the people in

that they had severe discolouration Results suggest that the public is

demand for tooth whitening and cosmetic dentistry is likely to increase

15 Prevalence of self-assessed tooth discolouration in the United Kingdom. Alkhatib MN, Holt R, Bedi R. J.Dent.2004:32: Results: 75% of those who assessed their tooth colour as normal were satisfied with that colour Females were less likely perceive having discoloured teeth than males Prevalence of discolouration appeared to increase with increasing age Smokers were more likely to perceive themselves as having discoloured teeth Prevalence of self-assessed tooth discolouration in the United Kingdom. Alkhatib MN, Holt R, Bedi R. J.Dent.2004:32: Results: Half of the people in the study perceived themselves to have tooth discolouration, 6% thought that they had severe discolouration Results suggest that the public is concerned about appearance in terms of tooth colour Findings suggest that demand for tooth whitening and cosmetic dentistry is likely to increase 15

16 Is the appearance of teeth important? The Importance of Dental Aesthetics Eyes and mouth are the two features most commonly associated with attractiveness (Baldwin DC.Community Dent.Oral Epidemiol.1980:8: ) Parents believe that orthodontic treatment will make their children better liked (Shaw WC et al. BrJOrthod.1991:6: ) Young adults with good dental aesthetics are more socially attractive (Shaw WC. Br.J.Plast Surg.1981:34: ) The Importance of Dental Aesthetics Attractive persons are considered more qualified and reliable (Linn EL. J.Health Hum Behav.1966:7: ) Unattractive persons are less well liked (Linn EL. J.Health Hum Behav.1966:7: ) Attractive persons receive better treatment (Christensen GJ. CRA News. 1981:5;1.) Other papers that show increased confidence when dental appearance is improved Poor dental aesthetics - lack of self confidence (Jenny J. et al., J.Dent.Res.1990:69:204) Dento-facial abnormalities - handicap in occupational goals (Jenny J.,Prosthek JM J.Canad.Dent.Assoc.1986:12: ) Good dental appearance is of importance if running for public office (Linn EL. J.Health Hum Behav.1966:7: ) Poor dental aesthetics - less chance of an interview (Jenny J.,Prosthek JM J.Canad.Dent.Assoc.1986:12: ) Other papers that show increased confidence when dental appearance is improved Davis LG, Ashworth PD, Spriggs LS Psychological effects of aesthetic dental treatment. J.Dent.1998:26: Ashworth PD, Davis LG, Spriggs LS. Personal change resulting from porcelain veneer treatment to improve the appearance of the teeth. Psychology, Health and Medicine.1996:1: Jenny J, Proshek JM. Visibility and prestige of occupations and the importance of dental appearance. J.Canad.Dent.Assn.1986:12:

17 Psychological effects of aesthetic dental treatment. Davis LG et al. J.Dent.1998:26: Patients referred to Sheffield DH who were unhappy with the appearance of their upper anterior teeth & for whom veneers were prescribed. Initial clinical and psychological assessment Minimal tooth preparation Review after 4 weeks and 6 months Dentist and patient review of aesthetics Cattell s 16PF Personality Inventory, and Body Esteem Scale used for assessment Psychological effects of aesthetic dental treatment. Davis LG et al. J.Dent.1998:26: RESULTS 25, from 64 patients referred, were treated with porcelain veneers 17 agreed to participate, with a total of 64 restorations Comparison group of 27 patients attending for routine examination No differences in personality assessments Significant changes in the Body Esteem scale with every subject changing in a +ve direction, whereas in the control group, 11 changed in ve direction and 16+ve. Significant change in ratings towards the ideal self Patients unhappy with their dental appearance: Avoid eye contact Tense oral musculature Cover mouth with hand when speaking After treatment: Changed hairstyle & makeup More open relaxed posture More assertiveness Davis LG et al. J.Dent.1998:26: Patients satisfaction with dental aesthetics. Samorodnitzky-Naveh GR et al. J.Dent. 2007:138: Subjects: 407 adults (18 to 26 years, 59% men) who had appointments at a military dental clinic Simple questionnaire regarding satisfaction with dental appearance 37% dissatisfied with dental appearance Reasons for dissatisfaction: 89% tooth colour 23% tooth alignment Fillings change teeth! Aesthetic dentistry changes lives! 17

18 What type of hypoplasia is this? 18

19 Reasons to use aesthetic techniques Patient need Patient demand High tech practice image Professional satisfaction? Working beyond the comfort zone Dental Aesthetics Tooth form Tooth preparation Masculinity/femininity Tooth size Tooth colour Dental Aesthetics Tooth visibility Symmetry Dental midline Gingival aesthetics In part 2 we will go through this list in detail. Thank you for listening 19

Gender Based Comparison of Gingival Zenith Esthetics Humagain M, Rokaya D, Srii R, Dixit S, Kafle D

Gender Based Comparison of Gingival Zenith Esthetics Humagain M, Rokaya D, Srii R, Dixit S, Kafle D ABSTRACT Background Department of Dentistry Kathmandu University School of Medical Sciences, Dhulikhel,