ANALYSISI OF DIAGNOSTIC RECORDS

DIAGNOSTIC RECORDS DIAGNOSTIC CAST RADIOGRAPHS : Lateral Cephalogram and orthopentomogram and others PHOTOGRAPHS OTHERS, According to case

DIAGNOSTIC CAST Symmetry and Space Space Analysis Tooth Size Analysis

SYMMETRY AND SPACE Can be checked with transparent ruled grid placed over the upper dental arch and oriented to the midpalatal raphe Asymmetry within the dental arch, but with symmetric arch form, also can occur in severely crowded cases because of * lateral drift of incisors due to premature loss of primary canine * one permanent canine being blocked out of the arch while the other is in its normal position. Drift of posterior teeth is usually caused by early loss of a primary molar, but sometimes develops even when primary teeth were exfoliated on a normal schedule.

SPACE ANALYSIS Space available – Space required = Space discrepancy Space available calculation ` * Sum of linear segments of dental arch * Contouring flexible brass wire on contact points of posterior teeth and incisal edges of anterior teeth. Space required calculation Sum of mesiodistal with of all teeth upto 1st molar.

FACTORS AFFECTINTG SPACE ANALYSIS Anteroposterior position of incisor; i.e. proclined or retroclined incisors. 1 degree labially tipped incisor will require 0.8 mm space to upright and v. v. Growth changes Migration of lower 1st permanatnt molar Curve of Spee Sum of C.O.S. depth of both side / 2 plus 0.5 mm = Space required to flatten the occlusal plane.

MIXED DENTITION SPACE ANALYSIS Radiographic Method Tanaka and Johnston Prediction Method Moyers Prediction Method Staley & Kerber’s Combination Method

RADIOGRAPHIC METHOD True width of primer molar Apparent width of primary molar = True width of unerupted premolar Apparent width of unerupted premolar Short comings of the method Advantages

TANAKA & JOHNSTON PREDICTION METHOD One half of the 10.5 mesiodistal mm width of + the four lower 11.0 incisors mm Estimated width of = mandibular canine and premolars in one quadrant Estimated width of = maxillary canine and premolars in one quadrant

ASHLEY HOWE’S ANALYSISS Total Tooth Material : Sum of mesiodistal width of all teeth mesial to the 2nd molar Premolar Diameter : Arch width between buccal cusp tip of right & left upper 1st premolars Premolar Basal Arch Width : Arch width between right and left canine fossae. (If it is not identifiable then 8 mm apical to interdental papilla distal to canine.)

Ashley Howe’s Inference If P.M.D.> P.M.B.A.W. :- Arch expansion is not possible If P.M.D.<P.M.B.A.W. :- Arch expansion is possible P.M.B.A.W. % = P.M.B.A.W. x 100 Total Tooth Material If the ratio is less than 37% :- Extraction Case. If it is between 37-44% :- Borderline case If it is above 44% :- Nonextraction Case

PONTS ANALYSIS S.I. :- Sum of mesiodistal width of maxillary four incisors M.P.V. :- Arch width between distal pits of right &left maxillary 1st premolars M.M.V. :- Arch width between mesial pits of right and left maxillary 1st molars C.P.V. :- S.I. x 100 80 C.M.V. :- S.I. x 100 64

Ponts Analysis Inference If measured value is less than calculated value, expansion is needed. The difference between calculated and measured value indicates amount of expansion required.

CAREY’S ANALYSIS Arch length mesial to 1st mandibular molar is measured. Mesiodistal widths of all mandibular teeth mesial to 1st molar is measured and is summed up. If the difference between these two value is < 2.5 mm :- Non extraction Case 2.5 - 5.o mm :- Borderline Case >5.0 mm :- Extraction Case

BOLTON’S ANALYSIS Sum of mesiodistal width of Maxillary 12 teeth upto 1st molar Sum of mesiodistal width of Mandibular 12 teeth upto 1st molar Sum of mesiodistal width of Maxillary 6 anterior teeth Sum of mesiodistal width of Mandibular 6 anterior teeth

Bolton’s Analysis Inference Overall ratio= Sum of mandibular 12 x 100 Sum of maxillary 12 Anterior ratio = Sum of mandibular 6 x 100 Sum of maxillary 6 Normal value for overall ratio is 91.3 and for anterior ratio is 77.2. By placing these value in the formula, discrepancy can be calculated.