APPLIANCE TREATMENT. CLASSIFICATION OF ORTHODONTIC APPLIANCES

Importance of the Subject: To achieve the goals of the orthodontic treatment, it is necessary to know classification, specification, general action, indications and contraindications of various orthodontic appliances. Removable, functional and fixed appliances differ by their action mechanism, active components, ways of fixation etc. To eliminate abnormalities of development of the maxillodental system and severe malocclusions at different age periods, various appliances should be used. There are age limits for use of the orthodontic appliances. Thus, an orthodontist should bear in mind indications and contraindications for different orthodontic appliances when using appliance therapy.

Objectives of education.

Main objective: to get acquainted with the classification of the orthodontic appliances, design and general principles of different types of orthodontic appliances, indications for their use in different age periods and for different tooth movement.

Specific objectives	Basic knowledge and skills
To develop skills in:
1. Taking social, medical and dental histories of a child to determine the risk factors of malocclusion development.	1. Taking social, medical and dental histories of an adult to determine the maxillodental system status (the Prosthodontic Dentistry Department).
2. General examination of a child (the gait and the carriage) and determining his maxillodental system status.	2. Determining the maxillodental system status of an adult (the Prosthodontic Dentistry Department).
3. Detecting facial signs and symptoms of malfunctions of swallowing, breathing, speaking, chewing and mandible movement.	3. Evaluating of functions of the maxillodental system of an adult (the Prosthodontic Dentistry Department).
4. To interpret classification of orthodontic appliances and to determine indications to different types of appliances.	4. To interpret classification of prosthodontics appliances (the Prosthodontic Dentistry Department).
5. Characterize different types of orthodontic appliances and their constructive peculiarities.	5. Characterize different types of prosthodontic appliances and their constructive peculiarities (the Prosthodontic Dentistry Department).

Determination and provision of basic knowledge and skills level Basic level control tests Test 1

Patient is 30 year-old. The oral cavity examination determined that dental formula is in accordance to age, but the frenulum of the upper lip is short, thick, intertwining with the gingival papilla. There is the 4 mm diastema on the maxilla. The mesiobuccal cusp of the first permanent molar of the maxilla occludes with the buccal groove of the first molar of the mandibular. The sum of the width of 12, 11, 21, and 22 is 27 mm. What factor causes the diastema?

1. Macrodentia.

2. Abnormality of the frenulum of the upper lip.

3. Macroglossia.

4. Adentia.

5. Harmful habits.

Test 2

19 year-old man. Intraoral examination revealed that the dental formula is in accordance to the patient age. There is an absence of contact of the upper and lower incisors and absence of the vertical overlap. The space between incisor edges of the upper incisors to the lower incisors is 4 mm in vertical plane. The patient has mouth breathing and infantile swallowing. He has got a biting habit (pencil biting).

What kind of malocclusion is there?

1. Anterior open bite.

2. Deep bite.

3. Anterior crossbite.

4. Mesial occlusion.

5. Distal occlusion.

Test 3

21 year-old woman. Intraoral examination revealed that the dental formula is in accordance to the patient age. There is the vertical space of 6 mm between the upper and lower incisors. The patient has nasal breathing; there are tension of the lips and tongue thrusting from the upper lip during swallowing.

What is the abnormal function of the maxillofacial system in this case?

1. Breathing through the mouth.

2. Infantile swallowing.

3. Mature swallowing.

4. Lazy chewing.

5. Harmful habit of cheek sucking.

Test 4

20 year-old man. The oral cavity examination determined the dental formula is in accordance to age. The overbite is 1/3 of the lower incisors. The mandibular incisors contact with the palatal surfaces of maxillary incisors. The midlines of both arches coincide. The mesiobuccal cusp of the maxillary first permanent molar occludes with buccal groove of the mandibular first molar. What occlusion is this?

1. Bimaxillary protrusion.

2. Crossbite.

3. Orthogenic occlusion.

4. Orthognathic occlusion.

5. Distal occlusion.

Test 5

32 year-old man. Extra-oral examination revealed that the proportion of the face is disturbed because of the lengthening of the lower face height. Intra-orally: there is the vertical space of 5 mm between upper and lower incisors. The patient has nasal breathing; there are tension of the lips and tongue thrusting from the upper lip during swallowing. What is the abnormal function of the maxillofacial system in this case?

1. Breathing through the mouth.

2. Infantile swallowing.

3. Mature swallowing.

4. Lazy chewing.

5. Harmful habit of cheek sucking.

KEYS

№ 1 - 2.

№ 2 - 1.

№ 3 - 2.

№ 4 - 3.

№ 5 - 2.

Information resources

1. Richard R Welbury. Paediatric Dentistry. 2002. Oxford. pp. 3 – 15.

2. Pinkam R Jimmy, et al. Pediatric Dentistry. 2005. Saunders. pp. 206, 275, 463.

3. Students' Guides and textbooks recommended by the Prosthodontic Dentistry Department.

Content of education in accordance with the objectives

Theoretical issues of the topic

1. Classification of orthodontic appliances.

2. Application of orthodontic appliances at different age periods. Indications and contraindications.

3. Functional appliances. Classification, indications, timing of treatment.

4. Removable mechanic appliances. General principles, indications, design.

5. Fixed appliances. General principles, indications, their conponents.

6. Combined appliances. General principles, indications, design.

Information resources

1. Bishara SE. Textbook of Orthodontics. 2001. Saunders. pp. 43 – 65.

2. Lecture materials.

3. Graphs, diagnostic algorithms, tables.

Additional books

1. Mitchel L. An introduction to orthodontics. 2001. Oxford, University Press. pp. 149 -175.

2. Mitchel L., David A Mitchell. Oxford Handbook of Clinical Dentistry. 2005. Oxford, University Press. pp. 66-67, 129 – 135.

3. Proffit WR, Fields HW. Contemporary orthodontics. 3nd edition St Louis: Mosby; 2000.

Indicative basis of actions

Instruction

Look at the Table 1 to know the types of the orthodontic appliances on different parameters.

To use the indications and contraindications of appliance therapy in different age periods you should study the scheme of approximate procedures.

Scheme of approximate procedures

Primary dentition (appliances can be used since 3 – 4 years, when a child is contact and realizes what he/she should do)
Probable indications to appliance therapy(1)		Probable contraindications to appliance therapy(2)		Appliance choice (3)
1. Stable harmful habits to 4 year-old period (e.g. sucking of the tongue, fingers, lips and cheeks)		1. Reluctance for treatment of parents. 2. Rather undisciplined, impatient child. 3. Parodontium disorders in child. 4. Poor appliance fixation on the deciduous teeth		1. Vestibular and oral plate. 2. Mandibular plate with a crib (an abutment for the tongue).
2. Premature loss of the deciduous teeth (for 1 year and more up to natural exfoliation), adentia.		1. Reluctance for treatment of parents. 2. Rather undisciplined, impatient child. 3. Parodontium disorders in child. 4. Poor appliance fixation on the deciduous teeth		1. Partial or complete removable dentures changed in 6 – 8 months.
3. Sagittal abnormalities of occlusion, mandibular enlargement, the sagittal overjet.		1. – “ – . 2. – “ – . 3. – “ – . 4. – “ – . 5. Decompensated caries.		1. Chin cup therapy with high pull. 2. Mandibular plate with buccal capping (for opening of occlusion)
Mixed dentition (appliance therapy becomes leading, indications are considerably widening)
1. Sagittal abnormalities of occlusion in frontal and buccal segments, poor mandibular development, excessive maxillary development, the increased overjet.		1. Reluctance for treatment of parents and child. 2. Parodontium disorders in child. 3. Decompensated caries.	1. Andresen- Häuple’s activator. 2. Fränkel’s functional regulator.
2. Anterior cross-bite.			1. Removable appliance with an active component (Z- spring, palatal screw), retention, posterior capping (to open the occlusion while the upper incisor move labially over the lowers).
3. Posterior cross-bite with displacement of the mandible.			1. Removable appliance with an active component (mid-line expansion screw, which is turned by parents once or twice a week), Adams clasps.
4. Space maintenance.			1. Acrylic appliance with clasps in the upper jaw, in the lower a lingual arch is better tolerated.
5. Digit – sucking habits			Plate with a crib (an abutment for the tongue), RA with a steeply inclined anterior bite plane, RA with a mid-line split in the acrylic of an expansion appliances.
Permanent dentition (appliance therapy is leading but in combination with surgery, wider use of mechanical and fixed appliances because of termination of active growth of the jaws)
1. Malocclusions in sagittal, vertical and transverse planes, abnormalities of functions and aesthetic deficiencies.	1. Reluctance for treatment of parents and offspring. 2. Parodontium disorders in child. 3. Decompensated caries. 4. Incapability of regular visit to an orthodontist. 5. Reluctance for treatment with extractions some permanent teeth.				1. Fixed appliances (bracket –systems). 2. Angle’s appliance.