Development of occlusion Pediatric dentistry

1. DEVELOPMENT OF OCCLUSION
SHREEPRIYA SINGHANIA
FIRST YEAR POST GRADUATE
DEPARTMENT OF PEDODONTICS AND PREVENTIVE DENTISTRY

2. CONTENTS
 Introduction
 Development of Occlusion
 Predental Period
 Deciduous Dentition Period
 Mixed Dentition Period
- First Transitional Period
- Inter transitional Period
- Second Transitional Period
 Permanent Dentition
 Self correcting anomalies
 Conclusion
 References

3. WHAT IS “OCCLUSION” ?
 Mosby’s dental dictionary (Zwemer;1998) defines occlusion as “a static
morphological tooth contact relationship”
 Acc. to Ash and Ramford , occlusion may be defined as “the contact
relationship of the teeth in function or para function”.
 Acc. to Angle, occlusion is “the normal relation of the occlusal inclined
planes of the teeth when the jaws are closed”.

4.  The term occlusion , however, refers not only to contact at an occlusal interface
but also to “ all those factors concerned with the development and
stability of the masticatory system and with the use of the teeth in
oral motor behavior ”
 In most instances, malocclusion and dentofacial deformity are not caused by
some pathological process, but by moderate distortions of normal
development.
 Therefore, knowledge of the process of occlusal development is necessary for
interception of malocclusion.

5. DEVELOPMENT OF OCCLUSION
 Development of occlusion is a genetically and environmentally
conditioned process.
 The various stages of occlusal development are:
1. Predental period
2. Deciduous dentition period
3. Mixed dentition period
4. Permanent dentition period

6. PREDENTAL PERIOD
 This period extends from birth until the eruption of the first
primary tooth. (at around 6-7 months)
 Alveolar process at the time of birth is called ‘Gum Pad’.
 They are horseshoe shaped pads that are pink, firm and
covered with a layer of dense periosteum.
 They are divided into two parts (labiobuccal and lingual) by
dental groove which is further divided into 10 segments by
the transverse groove, each segment having one dental sac.

7.  A very important landmark in gum pads is lateral sulcus, which is transverse groove between canine
and 1st molar. This is helpful in predicting inter-arch relation at a very early stage.
 Usually, the lower lateral sulcus is distal to the upper lateral sulcus.
 Maxillary gum pad is wider and longer than the mandibular thus when they are approximated, there
is complete overjet all around.
 The only contact that occurs is around the molar region while space exists in anterior region.
 This is called ‘Infantile Open Bite’ which is considered normal and helpful during suckling.

8.  The gum pads rapidly grow during the first year of life and the amount of growth is more in
the transverse direction.
 Length of the gum pad also increases mostly posteriorly to accommodate the deciduous first
and second molars.

9. DECIDUOUS DENTITION PERIOD
 The primary dentition stage extends from the
time of eruption of the primary teeth until
the eruption of the first permanent tooth
around 6 years of age.
 The initiation of primary teeth occurs during
first 6 weeks of intrauterine life and first
primary tooth erupts at the age of 6 months.
 The individual variations apart, it takes
around 2½ - 3½ years for all the primary
teeth to establish their occlusion.

10.  Deciduous teeth are formed more quickly than permanent teeth. The first deciduous teeth
erupts at 6 months of age while the first permanent one at 6 years.
 A deciduous incisor has only slightly more than 1 year for its formation while a permanent
incisor has almost 7 years.
Central
incisor
Lateral
Incisor
First
Molar
Canine
Second
Molar
SEQUENCE OF ERUPTION CHRONOLOGY OF ERUPTION

11. GROWTH OF THE JAWS
 In the newborn, mandible is posteriorly positioned in relation to the maxilla while during the
first year after birth, mandible attains a more anterior position than the maxilla.
 Sagittal relation of the jaws approaches the situation of complete deciduous dentition.
 More space is available for the formation of deciduous molars than for the deciduous incisors.
 Jaws are narrower in the anterior than the posterior regions. Deciduous incisors and canines are
not formed in the orientation in which they will erupt because the spatial conditions do not
allow it.

12.  A mandible of 20 week old foetus which shows it being narrower in the anterior
region where incisors are formed and broad where the molars are formed

13.  The median suture in the maxilla and symphysis of the mandible provide the largest contribution
to the early transverse development of the jaws.
 In the mandible the effect is of short duration and terminates with the ossification of symphysis
which happens 6 months after birth.
 However, maxillary median suture continues to contribute to the transverse growth of the maxilla
until the development of the dentition is completed.
 After the deciduous molars have reached the occlusion, the transverse growth of the maxilla is
adjusted based on the width of the mandible.

19. CONE – FUNNEL MECHANISM
 When erupting deciduous and permanent molars as well as premolars attain occlusal contact,
they are guided to optimal intercuspation by the cone- funnel mechanism.
 Cone- funnel mechanism acts for the first time when the opposing first deciduous molars touch
each other in which the eruption movements are guided by the slope of central fossa of the
mandibular molar.
 The adjustment of the eruption direction occurs more in the maxilla than mandible as the
morphology for the mandible is less suited for the purpose

21. COMPLETE DECIDUOUS DENTITION

22. PREVIOUS STUDIES
 Delabarre in 1819 described for the first time the spacing of anterior deciduous teeth between 4 to 6
years of age and suggested that the purpose was to make allowance for the permanent ones.
 In 1910, Zielinsky concluded that between 4 and 6 years, the upper anterior deciduous teeth move
forward and laterally and this causes the lower deciduous teeth to migrate forward into the enlarged
maxillary arch. This concept was termed physiological mesial shift.
 Clinch and Sillman were the first to present developmental series of dentitions from births.

23. Louis J Baume studied the biogenetic course of the deciduous dentition in
1949 and concluded that:
1.After the deciduous dental arches were completely formed, their sagittal and transversal dimensions were
not altered except when subjected to inadequate environmental influences.
2. Two consistent morphological arch forms of deciduous dentures were found; the arches were either
continuously spaced or continuously closed. Spaces in the deciduous denture were not developmental, but
congenital. Closed arches were on an average narrower transversally-than spaced ones.
3. The spaced arches frequently exhibited two distinct diastemata; one between the mandibular deciduous
canine and first deciduous molar and the other between the maxillary second deciduous incisor and
deciduous canine. These were interpreted as "primate spaces."
4. The terminal plane of the arches in occlusion remained constant.
5. Vertical growth of the alveolar processes concomitant with the development of the successional tooth
germs and sagittal growth concomitant with the development of the accessional tooth germs was observed.
6. The concept of physiological changes of the deciduous dental arches through spacing and through mesial
shifting of the mandibular teeth was not confirmed by the above observations.

24. CHARACTERISTIC FEATURES OF DECIDUOUS DENTITION
Spaced Dentition: Deciduous dentition is a spaced dentition. The spaces
in between the teeth can be utilized for adjustment of permanent incisors
which are always larger in compared to deciduous dentition. The spaces
present are of two types:
Primate spaces: Exist between the maxillary lateral incisors and the
canines, and mandibular canines and first molars. These spaces are also
called as anthropoid or simian spaces as they were initially found in our
ancestral simian species.

25. Physiologic spaces: Present in between all the primary teeth and play an important role in
normal development of the permanent dentition. Total space may vary from 0-8mm with
average of 4 mm in maxillary arch and 1-7mm with average of 3mm in the mandibular arch.

26. Non spaced dentition: This dentition is highlighted by lack of space between primary teeth
either due to small jaw or larger teeth. This type of dentition usually indicates crowding in the
developing permanent dentition.

27. Terminal Plane: The mesiodistal relation between the distal surfaces of the maxillary and
mandibular 2nd deciduous molars is called as terminal plane.
Physiological Tooth Migration And Its Significance For The Development Of Occlusion
I. The Biogenetic Course Of The Deciduous Dentition Louis J. Baume

28. Chandranee KN, Chandranee NJ, Nagpal D, Lamba G, Choudhari P, Hotwani K. Modified angle's classification for primary dentition.
Contemp clin dent 2017;8:617-20.
 Class i: When the mesiobuccal cusp of the primary maxillary second molar
occludes with the mesiobuccal groove of the primary mandibular second molar
 Class ii: When the mesiobuccal cusp of the primary maxillary second molar
occludes with the interdental space between primary mandibular first and
second molar
 Class iii: When the mesiobuccal cusp of the primary maxillary second molar
occludes with the distobuccal groove or distal surface of the primary
mandibular second molar.
MODIFIED ANGLE'S CLASSIFICATION FOR PRIMARY DENTITION
 Half cusp Class ii: When the mesiobuccal cusp of the primary maxillary second molar occludes with the
mesiobuccal cusp of the primary mandibular second molar
 Half cusp Class iii: When the mesiobuccal cusp of the primary maxillary second molar occludes with the
distobuccal cusp of the primary mandibular second molar
 Subdivision: When molar relationships on both sides in a child is different wherein one side is Class i and the
other being any one of the other types described above. The subdivision is the side which is not Class i side.

29. Chandranee KN, Chandranee NJ, Nagpal D, Lamba G, Choudhari P, Hotwani K.
Modified angle's classification for primary dentition. Contemp clin dent
2017;8:617-20.

30. TERMINAL PLANE
PREDICTION

31. MIXED DENTITION PERIOD
 The period during which both the primary and permanent teeth are present in the mouth
together is known as mixed dentition.
 The permanent teeth erupting in place of previous deciduous teeth are called as successional
teeth, whereas those erupting posteriorly to primary teeth are called as accessional teeth.
 Lasts 6 years-12 years of age.

32. MIXED
DENTITION
PERIOD
FIRST
TRANSITIONAL
PERIOD
Eruption of first
molars
Replacement of
Incisors
INTER
TRANSITIONAL
PERIOD
No Significant
Changes occur
SECOND
TRANSITIONAL
PERIOD
Replacement of
Canine and
Deciduous molars

33. SEQUENCE OF ERUPTION OF PERMANENT TEETH

34. FIRST TRANSITIONAL PERIOD: TRANSITION OF
INCISORS AND EMERGENCE OF 1ST PERMANENT MOLARS
 Prior to transition of incisors, usually at 6 years of age, the first permanent molars emerge: first
in the mandible, then in the maxilla.
 Continuing posterior growth provided sufficient space for them in the dental arch.
 They erupt perpendicular to the occlusal plane same as the deciduous molars erupted before
them.

35.  Occlusion of first permanent molar depends on their position in the jaw, the relationship between
mandible and maxilla and the mesiodistal crown dimensions of the teeth, particularly the
mandibular second deciduous molars.
 If the mandibular second deciduous molars have the same mesiodistal dimension as the
corresponding maxillary tooth, the terminal plane will have a mesial step.
 However in most cases, mesiodistal dimension is wider by a few millimetres which results in a
flush terminal plane.
 A good intercuspation of permanent molars cannot occur until the deciduous molars are replaced
by premolars and there is mesial migration of the permanent molars.

36. A comparative study of casts of 60 cases before and after the eruption of the, permanent molars
revealed three distinct kinds of normal molar adjustment:
1.In deciduous dentitions which terminated with a marked mesial step the first permanent molars
erupted immediately into normal cuspal interdigitation.
2. In spaced dentitions of Type I with a straight terminal plane It was observed that following the
eruption of first permanent molars, straight terminal plane had developed into mesial step. A
simultaneous closure of the lower primate space was concomitant with this process. The extent of
their mesial migration was corresponded with the width of that space.
3. In closed dentitions of Type II a mesial migration of the lower deciduous molars cannot occur
because of the absence of the primate spaces. The opposing permanent molars, Therefore, are
forced to erupt behind a straight terminal plane producing an end-to-end occlusion.
Louis J Baume studied the biogenesis of accessional dentition in
1949 in which

37. • It is a consistent observation that the permanent first molars move mesially whenever a space is
created anteriorly due to loss of contact as the result of caries, extraction, or physiological
shedding of a tooth.
• This indicates that a pressure in a mesial direction persists as long as the process of eruption of
accessional teeth goes on.
• On the basis of clinical studies three different mechanisms of normal occlusal adjustment have
been described:
1) The direct occurrence of a mesial step.
2) The early mesial shift of the lower first permanent molar effecting a closure of primate spaces.
3) The late mesial shift of the lower permanent molar subsequent to shedding of the deciduous
molars.(occurs in second transitional period)

38. Early Mesial Shift occurs in the first transitional period: the eruptive
forces of 1st permanent molars are strong enough to push the deciduous molars
forward in the arch thereby utilizing the primate spaces and thus establishing
Class I molar relation.

39. TRANSITION OF INCISORS
 Crown of permanent incisors and canines are broader than those of their
predecessors; this difference being greater in maxilla than in mandible.
 For the permanent incisors and canines, the circumference of that region
is smaller than the arch segment where their incisal margins will be
located. Again, this difference is greater in maxilla than in the mandible.
 In addition, the anterior area is smaller in relation to the sum of
mesiodistal crown dimensions of the 6 anterior teeth in the maxilla than
mandible.

40. Incisal liability:
 Was described by Warren Mayne in 1969.
 Permanent incisors are larger as compared to their primary counterparts and thus require
more space for their alignment.
 This difference between the space available and space required is called incisal liability .
(7.6 mm in the upper arch , 6mm in the lower arch.)

41. Space discrepancy is compensated by three mechanisms:
 Utilization of interdental spacing of primary incisors: Average of 4mm in maxillary
and 3 mm in mandibular arch. Primate space present in the upper arch mesial to primary
canine is also used.
 Increase in intercanine arch width: In males is 6mm for maxilla, 4mm for mandible and
In females 4.5mm for maxilla, 4mm for mandible.
 Increase in intercanine arch length: This due to growth of jaws.
 Change in interincisal angulation: Primary Incisors stand upright. The permanent
incisors which replace them are labially proclined placing them in a wider arch thus allowing
more proclination and gaining of space.

43.  Unlike deciduous incisors, permanent incisors erupt in the direction in which they
are formed.
 Maxillary lateral incisors emerge more labially than central incisors which is
reduced after eruption by the pressure exerted by the lips.
 In the mandible, the lateral incisors erupt slightly lingually to the dental arch and
subsequently migrate labially through pressure exerted by the tongue.

46. UGLY DUCKLING STAGE
 It is a transient form of malocclusion wherein midline
diastema is present between the maxillary central incisors.
 During the eruption stages of canine, canine will be
impinging on the roots of lateral incisors.
 This pressure causes the lateral incisor to erupt into the oral
cavity with divergence of crown distally.
 Even after the lateral incisor fully erupts this pressure effect
from the erupting canine persists.
 This pressure is transmitted to the central incisors which
causes the crowns to diverge and roots to converge towards
midline.
 This bilateral effect causes a midline diastema, which is
temporary.
 This temporary spacing that occurs between the CI and
sometimes between CI and LI gets closed automatically as the
canine comes into occlusion.

47. THE BIOGENESIS OF THE SUCCESSIONAL DENTITION :
LOUIS J BAUME
 1. Expansion of the dental arches in the anterior region, to accommodate the larger successional
incisors into proper alignment was brought about by a lateral and frontal alveolar growth during the
time of the eruption of these teeth.
 2. The mean increase in inter canine width was greater in the upper arches than in the lower ones,
and again greater in previously closed upper or lower deciduous arches than in previously spaced
ones.
 3. In the mandibular arches the strongest impulse of lateral growth was noted during the eruption of
the second incisors, in the maxillary arches during the eruption of the first incisors.
 4. An occasional "secondary" spacing of the upper deciduous anteriors occurred when the still
undeveloped maxillary arch was somewhat widened upon eruption of the permanent lower first
incisors.
 5. Spaced deciduous arches generally produced favourable alignment of the permanent incisors while
about 40 per cent of the arches without spaces produced crowded anteriors.
 6. The average amount of forward extension of the arches showed no difference between previously
spaced and closed arches but was 1.0mm. greater in the upper arches than in the lower ones.

48. INTER TRANSITIONAL PERIOD
 During the inter transitional period, the dental arches consist of permanent incisors, deciduous
canines, deciduous molars and first permanent molars.
 In maxilla the incisors are labially inclined. In addition to central diastema, there are frequently
other diastema in the maxillary anterior region.
 Initially there is some space between second deciduous molars and first permanent molars.

49.  In the mandible, lower incisors are less labially inclined. The incisal edges of the four mandibular
incisors are at the same level, while for maxilla, centrals are at a more occlusal level.
 The overjet is greater than in the deciduous dentition and also greater than the permanent dentition
is complete and jaw growth concluded.
 In both the jaws, the not yet emerged canines limit space for the roots of the incisors.
 Rotations of mandibular incisors are partially or fully corrected through pressure of tongue and lips,
provided that space is available.

51. CHANGES IN TOOTH POSITION
 The mesiodistal angulation of the incisors depends on the position of the permanent canine
crowns and their proximity to the roots of the lateral incisors.
 During the intertransitional period, the root formation of the emerged and not yet emerged
permanent teeth continues.
 The space for the elongation is created by the vertical growth of the jaws and an increase in the
height of the alveolar process.
 Characteristic for intertransitional period, is the dominance of the permanent incisors in the
face, particularly maxillary central incisors.

52.  During the inter transitional period, no or few changes are seen in the dental arches. However
many changes occur within the jaw.
 Preparations are made for the second transition. Roots of deciduous teeth and surrounding
bone resorb including the bone at the cervical regions.
 The crowns of the third molars start to mineralize, earlier in the maxilla than the mandible.
 At about the same time, furcation are formed in the adjacent second permanent molars. The
roots of the teeth still to emerge and elongate.

53. SECOND TRANSITIONAL PERIOD
 The second transitional period is associated with transition of canines and deciduous
molar/premolars and emergence of second permanent molars and lasts upto 1 to 1 ½ years.
 In contrast to a predictable emergence sequence of incisors, a large variations exists in the
sequence of emergence of permanent canines and premolars.
 The maxillary permanent canine is situated close to and above the first premolar, in which case
the premolar erupt first.

54.  The maxillary 2nd premolar has no such concavity and not two roots but only one: otherwise, the
crowns of the premolars are alike in shape and size.
 The most common sequence of emergence in maxilla: 1st premolar, canine, 2nd premolar.
 The most common sequence of emergence in mandible: canine, 1st premolar, 2nd premolar
 In mandible all possible variations in sequence of emergence can occur.

55. LEEWAY SPACE OF NANCE
 Deciduous molar have mesiodistally larger crowns than their
successors while the permanent canines are broader than their
predecessors, particularly in maxilla.
 The extra space needed for their replacement is usually available
because of presence of diastema.
 Premolars are located between and below or above the roots of the
deciduous molars.
 After the emergence of mandibular premolar, they are oriented
perpendicular to the occlusal plane, while the maxillary premolar are
buccally inclined and mesially angulated.

56.  Leeway space introduced by Nance in 1947, refers to space difference between the combined
mesiodistal dimension of deciduous canine, both molars and permanent canine and both
premolars.
 According to Nance, average difference for a maxillary quadrant is 1.8mm and same for mandible
is 3.4mm.
 The leeway space together with remaining diastema, offers space for good alignment of the canines
and premolars in the dental arch.
 With the excess space, the first permanent molars can move mesially, especially in the mandible
resulting in improved intercuspation.

57. Late mesial shift: Many children lack primate spaces and have a non spaced dentition and thus
erupting permanent molars are not able to establish Class I molar relation even as they erupt.
 In these cases, the molars establish Class I relation by drifting mesially and utilizing the Leeway
space after exfoliation of deciduous molars and this is called late mesial shift

58. COMPARISON OF ANTERIOR AND POSTERIOR
ERUPTION
 Alteration in angulation of the maxillary second and third molars has some similarity with
alteration in angulation of maxillary incisors.
 There is mesial migration of central incisors for closure of central diastema. A similar
phenomenon occurs in the molar region if extra space becomes available with the
replacement of deciduous molars is depleted by mesial migration of the permanent molars.
 The three molars erupt in the interval of 6 years while the jaw continues to grow posteriorly.
In the anterior region, lateral incisors emerge 1 year after the central incisors and jaw growth
is negligible

59. PERMANENT DENTITION
 After all permanent teeth except third molars have
emerged at 12 or 13 years of age, alterations in tooth
positions still takes place.
 After emergences of third molars, roots of the
maxillary permanent molars spread throughout the
available space.
 Distal margins of the maxillary first molars becomes
positioned more occlusally than the adjacent mesial
margins of the second molars.

60.  There is buccal inclination of the posterior teeth and labial with the anteriors.
 Mandibular premolars are oriented at perpendicular to the occlusal plane with the posteriors
being lingually inclined and anteriors labially inclined.

61. LATE CHANGES IN THE PERMANENT DENTITION
In both male and female subjects the
lips became more retruded
relative to the nose and chin
between 25 and 45 years of age.
1
In both male and female subjects
interincisor and intercanine arch
widths decreased. Also, total arch
lengths decreased and as a result
anterior crowding increased.
2
The changes in the various craniofacial skeletal profile and dental arch parameters between 25 and 45 years of
age were investigated by Bishara et al.

62. 1.Overlap: In normally occluding dentition the maxillary teeth are labial or buccal to mandibular
teeth.
2.Angulations: Permanent teeth will have buccolingual and mesiodistal angulations.
3.Occlusion: With the exception of mandibular central incisors and maxillary third molars, each
permanent tooth occludes with two teeth.
4.Arch Curvature: Anteroposterior curvature in the mandibular arch is called curve of spee.
Corresponding curve in the maxillary arch is called compensating curve.
Buccolingual curvature from one side to the other side is called Monson’s curve.
5.Overbite: Normal is 10-30%
6. Overjet: 1-3 mm
7.Molar Relationship: Class I molar is ideal.
FEATURES OF NORMAL OCCLUSION IN PERMANENT DENTITION

63. CHANGES IN THE OCCLUSAL PLANE
 The deciduous dentition has a flat occlusal plane. There is no or only a slight overbite. After
the transition, the permanent incisors erupt more than their predecessors.
 For an adult dentition overlap of one-third of the clinical crown height of the mandibular
central incisors is considered normal.
 This is greater in the inter transitional period as is the overjet which reduced after complete
permanent dentition is formed.

64.  After permanent incisors have completely erupted occlusal plane
is no longer flat; Curve of Spee is formed.
 Curve of Spee is the imaginary curve that is formed by buccal
cusp and incisal edges of the teeth in one arch.
 In the mandible, this curve is slightly concave, with the incisors
more occlusally positioned while for maxilla it is convex.
 Curve of Spee emerges with the eruption of mandibular
permanent incisors and first molars, increases with the
emergences of second molars and stabilizes the dentition

66. (1988)

68. EFFECTS OF OROFACIAL FUNCTION ON THE FACIAL COMPLEX
 Functional components dominate in the growth of face and development of dentition.
 There is a variation in the growth of structures of facial complex, for eg lymphoid tissues of the
adenoids and tonsils are large in early childhood and decrease in size after puberty.
 In children, tongue is especially large compared to the oral cavity also tongue before deciduous
dentition emerges, is positioned in between the jaws and cheeks.

69.  The most essential and vital activity of the orofacial region is breathing.
 The size of nostrils is the restricting factor in the amount of air that can pass through the nose.
Excessive mouth breathing is effect of limitation in nasal passage.
 In young children, enlarged and infected adenoids usually limit the passage.
 Long-lasting abnormal breathing modes affect the position of tongue, lips and teeth.

70.  Swallowing movements can be distinguished in three modes: the infantile, the transitional and the
adult.

71.  It is generally true that to affect the morphology of the facial skeleton and position of
teeth, a constant pressure must be exerted for atleast 6 hours a day.
 Consequently swallowing does not affect tooth position and facial morphology.
 Hence a deviating swallowing cannot cause an open bite or malocclusion; infact the
swallowing movements adjust to the morphologic situation rather than the other way
around.

72.  Chewing, another activity of the orofacial region, also has no effect on tooth position. The
forces involved are too varied and too short in duration
 This is true even for speech. Individuals with excellent occlusion may have impaired speech
and those with severe malocclusion do not necessarily have any speech defects.
 In conclusion, in the short term, functional activities adapt to the form, while in the long
term, functional activities affect the structural form.

73. SELF- CORRECTING ANOMALIES

74. CONCLUSION
 An ideal occlusion, as defined in dentistry, is not
encountered often.
 An ideal occlusion is a concept created and accepted
by dentists and orthodontists that serves as the goal
for realizing an optimal Aesthetic and functional result
with orthodontic treatment.
 The size, form and relation of the jaws and
configuration and structure of face sometimes limit the
realization of the ideal goal.

75. REFERENCES
 Textbook of Pediatric Dentistry – Nikhil Marwah
 Textbook of Pedodontics – Shobha Tandon
 Textbook of Orthodontics-Bishara
 Textbook of Orthodontics- Shridhar Premkumar
 Theoretical and practical aspects of crowding in the human dentition – Van Der Linden
 Baume,L.J.: Physiological Tooth Migration and Its Significance for the Development of Occlusion. I. The Biogenetic
Course of the Deciduous Dentition ,J.D.Res.29: 123, 1950.
 Baume,L.J.: Physiological Tooth Migration and Its Significance for the Development of Occlusion. II. The Biogenesis of
Accessional Dentition ,J.D.Res.29:331,1950.
 Baume, L. J.: Physiological Tooth Migration and Its Significance for the Development of Occlusion. III. Biogenesis of
Successional Dentition, J. D. Res. 29: 338, 1950

76. THANK YOU !