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- 1. Dr Bushra Naeem BOLTON ANALYSIS AND MIXED DENTITION
ANALYSIS
- 2. BOLTON ANALYSIS
- 3. Bolton analysis According to Bolton there exist a ratio
between the mesiodistal width of maxillary and mandibular teeth
Bolton analysis helps in determining tooth size discrepancy
- 4. Determining overall ratio Mesiodistal width of all the teeth
which are mesial to the permanent 2nd molar is measured Overall
ratio= Sum of mandibular 12 x 100 Sum of maxillary 12
- 5. If the ratio is less than 91.3% it indicates maxillary tooth
material excess Amount of excess can be calculated by Sum of
maxillary 12- sum of mandibular 12 100 91.3
- 6. If the ratio is greater than 91.3% it indicates mandibular
tooth material excess Amount of excess can be calculated by sum of
mandibular 12- sum of maxillary 12 91.3 100
- 7. Anterior Ratio Mesidistal width of all anterior 6 maxillary
and mandibular anterior teeth is measured Anterior ratio= sum of
mandibular 6 100 sum of maxillary 6
- 8. If the ratio is less than 77.2% it indicates maxillary
anterior excess material . Amount of excess material can be
calculated by Sum of maxillary 6- sum of mandibular 6 100 77.2
- 9. If the ratio is greater than 77.2% it indicates mandibular
anterior excess material Amount of excess can be calculated by sum
of mandibular 6 sum of maxillary 6 77.2 100
- 10. MIXED DENTITION ANALYSIS The purpose of mixed dentition
analysis is to evaluate the amount of space available in the arch
for eruption permanent canine and premolars This can be achieved by
predicting the mesiodistal width of unerupted premolars and
canine
- 11. Methods Radiographic method Moyers prediction table Tanaka
and johnston equation Staley kerber method
- 12. Radiographic method Also known as Hukabas analysis With any
type of radiograph, it is necessary to compensate for the
radiographic enlargement, this can be achieved by measuring the
object which is available on both radiograph and the cast.
- 13. A proportional relationship is set up true width of primary
molar= apparent width of primary molar true width of unerupted
premolar apparent width of unerupted premolar
- 14. This technique can be used on maxillary and mandibular
arches for all ethnic groups Its accuracy depends on the quality of
the radiograph
- 15. Moyers prediction table Moyers predicted the combined
mesiodistal width of canine and premolars based on the sum of lower
4 incisors Based on this calculation, the expected width of canine
and premolars is predicted by referring the Moyers prediction
values.
- 16. Moyers prediction values Total mandibular incisors width
19.5 20.0 20.5 21.0 21.5 22.0 22.5 23.0 Predicted values of canine
and premolar maxilla 20.6 20.9 21.2 21.3 21.8 22.0 22.3 22.6
mandible 20.1 20.4 20.7 21.0 21.3 21.6 21.9 22.2
- 17. Accuracy of this method is fairly good for European white
children on whom data was tabulated No radiograph required
- 18. Tanaka and johnston Tanaka and johnston developed another
way of using the width of lower 4 incisors to predict the size of
canine and premolars. Mesiodistal width of lower 4 incisors is
obtained and an equation is applied.
- 19. Estimated width of lower canine and premolar of one
quadrant= of the mesiodistal width of 4 incisors+10.5mm Estimated
width of upper canine and premolar of one quadrant= of the
mesiodistal width of 4 incisors+11mm
- 20. Staley kerber graph Combination of radiographic and
prediction table method Mesiodistal width of central and lateral
lower incisors is measured from the cast. Determine the width of
premolars from the periapical radiograph. Sum up the mesiodistal
width of central and lateral incisors and premolars of that
particular side Staley and kerber graph allows canine width to be
read directly from the sum of incisors and premolars width
- 21. This method can only be used on mandibular arch Quite
accurate for European ancestry
- 22. Which method to be used?
- 23. THANK YOU