This document discusses the history and development of lingual orthodontic therapy. It notes that Kinya Fujita introduced the first lingual appliance system in the 1970s. It describes some of the initial challenges with lingual appliances, such as shear forces causing bracket failure and poor oral hygiene. Modern lingual brackets have been redesigned to address these issues through features like inclined planes and reduced profiles. The document also discusses the importance of precise bracket placement, which has benefited from techniques like indirect bonding using custom setups on diagnostic models. Lingual orthodontics continues to develop through organizations like the American Lingual Orthodontic Association established in 1987.

1. Lingual orthodontic
By Dr .ZAID. AlDEWACHI, MSC, ORTHODONTIC, high
speciality in lingual orthodontic &micro implant

2. Main purpose of orthodontic treatment;
1.Esthetic
2. function.
3,. Stability.
.4
Good oral health.
.4
. Kinya Fujita introduced
lingual appliance system

7. Development of Fujita
Actual research :1971
Edgewise &Begg:1975
Lingual bracket:1976
First case reported:1978

8. Slot types &size of lingual bracket
Fujita: occlusal (0.020&0.019)sequre wire
Lingual (0.018 edgewise wire &0.028round wire
Vertical slot:0.016 sequre wire
Ormco: lingual slot 0.018,0.022 edge wise wire
0.016sequre wire
Unitek: occlusal slot only :
Dentaurum occlusal (0.020 sequre wire
Vertical 0.016

10. Uses of slot
1.Occlusal slot: easy of insertion and
removal of the wires.
2.Horizontal slot: easy of correct the
vertical movement in addition to the
correction of the torque and
angulation.
3.Vertical slot: useful to the use of
various auxillaries.

12. the development of lingual orthodontic therapy and
the current solutions:

13. Why it is difficult?
1.Shear of bracket.
2.Arch wire ligation.
3.Deep bite.
4.Precise bracket positioning.
5.Precise wire bending.
6.Treatment quality.
7.Anchorage control.
8.Poor posture during treatment.

15. 1. Tissue Irritation and Speech Difficulties
The earlier brackets placed on the lingual surface of the teeth were irritating to the
tongue and impeded normal speech. The current generation of brackets has been
Initially, anterior brackets had long
gingival hooks responsible for calculus build-up.
10 LINGUAL ORTHODONTICS
redesigned with smooth exterior surfaces and a low profile. The increased comfort
allows normal tongue activity, hence speech is not affected significantly.
2. Gingival Impingement
Earlier generations of the lingual appliance had a broad bonding base extending
towards the gingival margin . Access for adequate oral hygiene and the
self-cleansing nature of the oral cavity were compromised. Brackets have been
redesigned to be more self-cleansing. The base now extends incisally and mesiodistally,
providing adequate bond strength, yet retaining hygienic qualities. The mandibular
anterior teeth are particularly vulnerable to calculus accumulation due to their close
proximity to the submandibular salivary glands. These brackets have 1.5 to 2 mm
clearance between the base and the gingival margin. Additionally, the bracket hooks
have been redesigned with a lower profile and are located several millimeters from the
gingival margin .

17. 3. Occlusal Interference
A predominant problem with the original appliance was the effect of the shearing
forces on the brackets, particularly in the maxillary anterior dentition. (In the absence
of a cross-bite, the lingual aspect of the mandibular dentition is generally not in direct
contact with the maxillary dentition; therefore, the shearing forces were not a problem
(Likewise, the relatively high maxillary crown height and low mandibular
cusp height in the posterior segments allow adequate clearance to avoid the severe
shearing forces seen in the maxillary anterior region.) The bracket was redesigned with
an inclined or bite plane strategically placed to redirect the vertical shearing forces to a
horizontal seating force . The location of the inclined plane is such that
when a 1 mm over jet and overbite relationship is obtained, all mandibular anterior
contact with the inclined plane is eliminated. To avoid these effects caused by
tooth contact with the arch wire, the inclined plane is located incisal to the slot.
.

20. 9. Ligation
To permit stable ligation with ligature wires or A elastics, ligature locking
grooves that
are both deep set and easy to hook have been designed. When teeth
are crowded and
slot engagement is especially difficult, a vertical slot is provided so the
arch wire can
be attached to the bracket even through the initial stages of leveling and
aligning
(A double over-tie with metal is used when a tooth is to be an
attachment
for anchorage or rotation of the other teeth.

21. Appliance Placement and Bonding
The original appliances were direct bonded. With the variability of lingual tooth
contours,
accurate bracket placement was difficult. This approach produced unpredictable
tooth alignment with tremendous variations in tip, torque, and tooth height.
Initially,
the Torque Angulation Referencing Guide (TARG) system was used. The TARG
instrument was designed to place brackets on the lingual surfaces using
conventional
landmarks as references. Although substantial improvements were made in the
accuracy
and efficiency of bonding, the system was still inadequate. A more sophisticated
system,
using a diagnostic set-up constructed from articulated models was developed and
has met with considerable success. This method, the Custom Lingual Appliance
Set-Up Service (CLASS), involves indirect bonding set-up on a diagnostic or ideal
model of the teeth. The brackets are then transferred back to the original
malocclusion,
and transfer trays prepared..

23. Why precise bracket positioning;;;;;;
. 1.Less arch wire bending .
2.Less chair time .
3.Less treatment time.
4. Better treatment quality.
5.Reducing relapse.
Considering factors in bracket positioning.
1.Vertical height.
2.Horizontal rotation.
3.Axial angulation.
4.Torque inclination

32. Bends of
lingual
orthodontic

34. The American Lingual Orthodontic Association (ALOA) was established
on
November 14, 1987, by a core group of six hundred American orthodontists.
Membership
quickly grew to over 800 members in 17 countries. The ALOA provided quarterly
journals, study club assistance, patient brochures, yearly conventions, and professional
lectures. The first annual meeting of ALOA was held in Washington in 1987, and in
Palm Springs the following year.
Japanese university programs offered training in lingual therapy and
these were soon
followed by courses in Korea, South America, Mexico, and Denmark.
The European Society of Lingual Orthodontics (ESLO) was founded in
1992, in
Venice, Italy, and hundreds of people participated in the first European
lingual association

35. Center of rotation
of palatal root