Smile analysis in vertical dimention:- factors to be considered when observed by orthodontist

44
SMILE ANALYSIS IN VERTICAL DIMENTION Presented by:- Dr. Maulik patel

description

This is article description of smile when observing in vertical dimension ,maily used by dentist (orthodontist) while treatment of gummy smile with braces.

Transcript of Smile analysis in vertical dimention:- factors to be considered when observed by orthodontist

  • 1.Presented by:- Dr. Maulik patel

2. GOOD MORNING!!!! 3. Macro Esthetics Mini Esthetics Micro Esthetics 4. Symmetry dental Midline And skeletal Midline Vertical Tooth lip relation:- Cant Of Occlusal Plane:- 5. Social smile/posed smile/Reproducible(orthodontic diagnosis) Enjoyment Smile/Duchenne smile in research lit. 6. The smile arc is defined as the relationship of the curvature of the incisal edges of the maxillary incisors and canines to the curvature of the lower lip in the posed smile. 7. Consonant NonConsonant Reversed Flattened Classified As:- 8. The most important factor in smile Esthetic is smile arc and only one that can change the rating of smile from acceptable to unesthetic. It should be monitored during the treatment. Ker AJ,Chan R,Field HW,et al:- Esthetics and smile charecteristics from the laypersons perspective: a computer based survey study. J Am Dent Assoc 139:1318-1327,2008 9. The purpose of this article is to discuss some new concepts of the desirable characteristics of tooth display during normal conversation and smiling, and to provide guidance on how to analyze esthetic factors by viewing the patient from the front. It will emphasize the need for age-related goals in orthodontics. 10. Evaluating esthetics from the front in conversation ,facial expressions, and smilling. Factors analyzed by sitting or standing in front of the patient. Crown length of incisors Incisal edge contours Axial inclinations Midlines crown torque Smile line Lombardi, R.E:- The pinciples of visual perception and their clinical implications in denture prosthesis,J Prosth. Dent. 1973 11. Each pt should be coached and asked to achieve the same lip position at least twice in succession before photograph is taken. A short video sequence will be helpfull in demostrating rest position, Normal conversation, and smilling. In Rest position the teeth should be slightly apart and the perioral soft tissue and mandibular posture both must be unstrained. At full smile the teeth should be lightly closed. 12. The smile is apparently formed in two stages, the first raising the lip to the nasolabial fold, and the second involving further superior raising of the lip and the fold by three muscle groups. Nearly everyone, irrespective of age, will display the maxillary incisors nicely on maximum smiling, even if only the mandibular incisors are visible during conversation. 13. Tjan, miller performed a semi quantitative study of smile-line variations;their data suggest evidence of sexual dimorphism of smile lines in the vertical dimention. Full face photographs of smilling men and women were analysed with the intention of identifying features of lip position for help in designing esthetic dental restorations. 14. Low smile line were predominant in Male High smile line were predominant in Females 15. Low smile less than 75% of clinical crown height of maxillary anterior teeth. Aveage Smile 75-100% of maxillary anterior crown height. High smile Exposing continuous band of gingiva. 16. The correction of deep overbite can be accomplished by various combinations of intrusion of the anterior teeth and extrusion of the posterior teeth. A serious mistake commonly made is orthodontic practice is "overintrusion" of the maxillary incisors. 17. Unesthetic result after overintrusion of maxillary incisors, and straight incisal curvature in relation to lower lip 18. The best treatment strategy in the majority of deep overbite cases is to actively intrude the mandibular incisors, using double tubes on the mandibular first molars and continuous or segmented base arches or utility arches. In a young patient with a short lower face, extrusion of the posterior teeth might correct a deep overbite, but 19. Another common mistake in orthodontic finishing is to create a straight (or even reverse) maxillary incisal curve relative to the smile line ( Fig.B,D). Parallelism of the incisal curve and the inner contour of the lower lip in smiling may seem difficult to produce. In practice, however, this appearance can readily be achieved if the maxillary central incisors are symmetrically positioned 0.5mm longer than the lateral incisors. 20. If the lower lip shows a marked curvature in smiling, the distoincisal edges of the maxillary central incisors can be ground slightly without affecting functional occlusion. It is particularly undesirable to combine maxillary incisor overintrusion with a straight arrangement of these teeth. 21. Etiology for gummy smile Biologic mechanism underlying the gingival smile line Anterior maxillary excess(2-3 mm) excess Greater muscular capacity to raise the upper lip on smilling Supplemental associated factors including Excessive overjet ,excessive interlabial gap at rest and excessive overbite. Variables not associated Uppere lip length Incisor crown height Mandibular plane angle Palatal palne angle 22. 1) Upper Lip Length What is significant, however, is the relationship of the upper lip to the maxillary incisors and to the commissures of the mouth. 23. The average lip length at rest, as measured from subnasale to the most inferior portion of the upper lip at the midline, is about 23mm in males and 20mm in females (Table 1). 24. It is not easy to alter commissure height, but lip lengthening is possible with lip surgery, either as a single procedure or in combination with a Le Fort I osteotomy. A short upper lip is not always associated with a high lip line; on the contrary, the upper lip was found to be longer in a gingival-display group than in a non- displaying sample. Peck, S.; Peck, L.; and Kataja, M.: The gingival smile line, Angle Orthod. 62:91-100, 1992. 25. 2) Lip elevation: In smiling, the upper lip is elevated by about 80% of its original length, displaying 10mm of the maxillary incisors. Women have 3.5% more lip elevation than Men. There is considerable individual variability in upper lip elevation from rest position to the full smile, ranging from 2-12mm, with an average of 7- 8mm. 26. Hypermobile Hypomobile More elevation of lip and gingival display on smile Aggressive Intrusion of incisors- less or no incisal display at rest./ older look Low lip line on smile Extensive incisor extrusion -an overbite with excessive incisor display at rest. 27. 3)Vertical maxillary excess When upper lip length and mobility are normal, a gingival smile with excessive incisor display at rest can be attributed to vertical maxillary excess. Treatment is disimpacting the maxilla vertically up, the best reference is the incisor display at rest, taking upper lip length and any incisor attrition into account. 28. Short upper lip should not be treated by lefort I. It should also be noted that in maxillary impaction, the upper lip shortens by as much as 50% of the surgical skeletal intrusion. 29. 4) Crown height The average vertical height of the maxillary central incisor is 10.6mm in males and 9.8mm in females. A short crown can be due to Attrition or Excessive gingival encroachment. 30. A gingivectomy or a crown-lengthening procedure with crestal bone removal is recommended when short clinical crowns are associated with a gingival smile and a normal incisor display at rest. 31. 5) Vertical dental height:- Deep bite: Openbite :- if incisor exposure is proper correction done by posterior teeth intrusion and if incisor display at rest is not proper it is corrected by extrusion of incisors. 32. Gingival contours and clinical crown length descrepancies their diagnosis and treatment options are described in this article. Also how to Enhence Restorative, Esthetic , and Periodontal results with orthodontic therapy. 33. (Am J Orthod Dentofacial Orthop 2003;124:116-27) 34. In a direct measurement study of more than 3500 subjects, Dickens et al; The effects of maturation and aging on the soft tissues can be summarized as :- (1) Lengthening of the resting philtrum and commissure heights, (2) Decrease in turgor (or tissue fleshiness), (3) Decrease in incisor display at rest, And during smile, (4) Decrease in gingival display during smile. 35. Smile changes with increase in age and differs between males and females. As age advances, the loss of resting muscle tone and increased flaccidity and redundancy contribute more in lowering of the smile height than the decreased muscles ability to create a smile. Males have more vertical movements whereas females have more horizontal movements during smile. Angle Orthod. 2013;83:9096. Patil Chetana; Pradeep Tandonb; Gulshan K. Singhc; Amit Nagard; Veerendra Prasade; Vinay K.Chughf 36. There should be studies which are done on indian local population. Which include laypersons opinion and orthodontist perception so that the esthetic goals can be achieved which are socially and scientifically acceptable. The studies should be done on longitudnal basis most sudies are on cross sectional.