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

6.  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

7.  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

8. 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

9.  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

10.  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

11. 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

12. Methods
 Radiographic method
 Moyers prediction table
 Tanaka and johnston equation
 Staley kerber method

13. Radiographic method
 Also known as Hukaba’s 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.

14.  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

15.  This technique can be used on maxillary and
mandibular arches for all ethnic groups
 Its accuracy depends on the quality of the
radiograph

16. 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.

17. 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

18.  Accuracy of this method is fairly good for
European white children on whom data was
tabulated
 No radiograph required

19. 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.

20. Estimated width of lower canine and premolar of one
quadrant=
½ of the mesiodistal width of 4 incisors+10.5mm
Estimated width of upper canine and premolar of one
quadrant=
½ of the mesiodistal width of 4 incisors+11mm

21. 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

22.  This method can only be used on mandibular
arch
 Quite accurate for European ancestry

23. Which method to be used?

24. THANK YOU