ortho- treatment planning and management of class i malocclusion

8/3/2019 ORTHO- Treatment Planning and Management of Class I Malocclusion

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TREATMENT PLANNING



Introduction

Treatment planning is the second step in the treatment ofany patient; the first step being diagnosis of the problem.

It entails the formulation of a detailed problem list, setting upof treatment objectives, and finalizing the treatment plan afterdiscussing it with the patient or the patient's guardians.

It also involves, planning space requirements, choice of

appliance and the retention regimen.



DIAGNOSIS

Orthodontic diagnosis involves three steps - collection ofdata, processing of the collected data and finally drawingconclusions.

Step one involves the taking of case history, intraoral and

extra-oral examination of the patient, making of study modelsand taking the relevant radiographs or other diagnosticrecords.

The second step involves the processing of all this collected

information into understandable and coherent data. This willinvolve undertaking cephalogram and study model analyses.

The resulting information should be able to give a conciseand exact location of the malocclusion.



A statement of diagnosis should include the exact problem asperceived by the clinician and why and/or what is (etiology)causing the problem.

For example: a 12-year-oldmale patient, suffering from mildcrowding of the upper and lower anterior teeth, with a Class II

skeletal and dental malocclusion due to a short and retro-positioned mandible with proclined upper anteriors and anopen bite of 2mm due to persistent thumb sucking habit.

Another important aspect, which the diagnosis should reflect

upon, is the growth potential.



PROBLEM LISTSkeletal

Dental

Functional

Soft Tissue

TREATMENT OBJECTIVE

Enlist he problems that have to be attended to in a decreasing orderof priority

Patient’s chief complaint and desires should be given adequateweightage

Must be realistic in setting up objectives and important to remember thegoals of orthodontic treatment - functional efficiency, structural balance andesthetic harmony (Jackson's triad )



PLANNING SPACE REQUIREMENTS

Corrections required as part of treatment:

1. Retraction of protruded teeth

2. Correction of crowding

3. Alignment of rotated anterior teeth

4. Alignment of rotated posterior teeth

5. Correction of molar relationship

6. Levelling the curve of Spee



RETRACTION OF PROTRUDED TEETH

For every millimeter of retraction required, 2 mm of space isrequired.

Protruded teeth are the most frequent reason for patients to approach theorthodontist. Unless the retraction required is very less or / and the dentalarches are spaced, extraction of certain teeth might be required to createspace for retraction of proclined teeth.

CORRECTION OF CROWDING

For every millimeter of decrowding, tile same amount of space isrequired for aligning tile teeth.

Crowded teeth are as unsightly as proclined teeth but maybe more harmfulfor the gums. The correction of crowding requires calculating the exactmesiodistal dimensions of the teeth to be aligned and accordingly space canbe created for alignment. Use of Kesling's diagnostic setup can be of

additional help.



ALIGNMENT OF ROTATED ANTERIOR TEETH

For every millimeter of derotation required, the same amount ofspace is required for aligning the teeth.

The anterior teeth are broader mesiodistally and occupy less space whenthey are rotated. Alignment of such teeth requires additional space in thedental arch.

ALIGNMENT OF ROTATED POSTERIOR TEETH

Space is created when rotated posterior teeth are aligned. The

space created depends upon the tooth and the amount of rotationpresent.

When posterior teeth are rotated, they occupy more space; hence, space isactually created by aligning such teeth.



CORRECTION OF MOLAR RELATIONSHIP

The space required for mesial or disial movement of the molars is asper the actual movement planned.

To achieve a stable molar relationship, it is essential to have a full Class I orII. End-on relation is not stable and space might be required to bring themaxillary or mandibular molar mesially to achieve stability. The exact spacerequired can be calculated on the study models.

LEVELLlNG THE CURVE OF SPEE

F or every 1mm of levelling, approximately / mm of space is required.

Skeletal malocclusions are very commonly associated with an increase in thecurve of Spee. An excessive curve will not only limit the amount of retractionof the maxillary anteriors but can also aid in the relapse of the condition.



PLANNING ANCHORAGE

Anchorage consideration forms an important part of thetreatment planning exercise

All efforts should be taken to minimize unwanted tooth

movements

Failure to plan anchorage invariably results in failure oftreatment mechanics



Anchorage demand for an individual patient depends on:

1. Number of teeth being moved – the greater the number ofteeth being moved, the greater would be the demand onanchorage

2. Type of teeth – tooth movement involving multi-rootedposteriors offer greater strain on anchorage that movingsmaller teeth

3. Type of tooth movement – tipping movement are less

demanding on anchorage than bodily

4. Duration or treatment – Complicated treatments ofprolonged duration strains the anchor teeth



SELECTION OF APPLIANCE

Based on a number of Factors

1. The type of tooth movements required

2. Patient's expectations

3. Growth potential of the patient

4. Patient's ability to maintain oral hygiene

5. The cost of the treatment

6. The skills of the treating clinician.



THE TYPE OF TOOTH MOVEMENTS REQUIRED

Simple tipping movements can be achieved using removable appliances.

If multiple, complex tooth movements are desired, it is advisable to use oneof the available fixed orthodontic appliances.

PATIENT'S EXPECTATIONS

Patients who have high expectations are expecting ideal finishes which mightnot be possible using removable appliances.

Such patients are concerned about their esthetics to such an extent that thelabial appliances might not be an option. They might desire the use of lingual

appliances.

A compromise might need to be arrived at regarding treatment results andthe patient's expectations, it is advised to inform the patient exactly what isachievable with which appliance, to the best of the clinician's ability beforecommencing the treatment.



GROWTH POTENTIAL OF THE PATIENT

Growing patients who exhibit skeletal malocclusion should be treated withappliances that modulate the growth.

Results achieved during growth are more stable yet sometimes the return ofan aberrant growth pattern following completion of treatment can result inrelapse of the treatment results.

PATIENT'S ABILITY TO MAINTAIN ORAL HYGIENE

Certain age groups or patients with compromised motor functions might notbe able to maintain adequate oral hygiene with fixed appliance therapy. Suchpatients can be treated using removable appliances with compromisedtreatment results.



THE COST OF THE TREATMENT

Fixed orthodontic treatment is more costly as compared to removableappliance therapy. Sometimes the patient might not be able to afford costlyyet ideal treatment plans.

The financial implications of the treatment should be considered andexplained to the patient at the time of deciding upon a particular treatment

plan.

THE SKILLS OF THE TREATING CLINICIAN

It is the duty of the clinician to choose an appliance that is appropriate for the

particular case and not just appropriate for the clinician.

It is always better to work within your means and to present treatment plansthat can be achieved.



PLANNING RETENTION

It is now accepted that teeth once moved, tend to go back to their initialposition. The potential for relapse is increased by the presence of certainfactors, which are

Stretched periodontal ligament – the stretched gingival fibers are a frequent

cause of relapse in case of rotated teeth, since these fibers take a long timeto reorganize around their new position

Unstable occlusion – teeth placed in unstable position at the end oforthodontic therapy tend to relapse

Continuation of growth pattern – Continuation of the growth pattern that hascaused a skeletal malocclusion after orthodontic therapy results inresurfacing of the malocclusion after treatment



DISCUSSION WITH THE PATIENT AND PATIENT

CONSENT

Patient today act as co-decision makers. Hence, it is the orthodontist legaland moral duty to discuss the risk/benefit of the treatment and alternatives aswell as the risks of no treatment at all.

Informed consent can and should be taken after providing the patient with

enough information to have an understanding of the condition (malocclusion),its severity and the proposed treatment-its goals and objectives.

Patient should be made to understand the commitment required on his/herpart-both regards to the time and financial.

Risks involved, of the treatment and of not getting treatment, should also beexplained.



MANAGEMENT

OFCLASS I MALOCCLUSIONS



MIDLINE DIASTEMA

Midline diastema refers to anterior midline spacing between the twomaxillary central incisors

It is one of the most frequently seen malocclusions that is considered easy totreat but difficult to retain

Causes for midline diastema:

◦ Transient malocclusion

◦ Tooth material – arch length discrepancy (peg laterals, microdontic laterals)

◦ Unerputed mesiodens

◦ Abnormal frenal attachment

◦ Proclination

◦ Midline pathology

◦ Iatrogenic

◦ Pressure habits



Supernumerary

Iatrogenic



Peg laterals

Spacing



Proclination

MissingLaterals



Habits

High Frenum



MANAGEMENT

Removal of Cause

Active treatment

Retention

Cosmetic restorations



SPACING The presence of spacing between teeth is one of the commonly seen

manifestations of a Class I malocclusion.

Spaces can be in localized area or the entire arch can exhibit spacing

Etiology

1. Arch length – tooth size discrepancy2. Habits

3. Abnormally large tongue – tongue thrusting

Diagnosis

1. Model analysis2. Radiographic examination – any impacted, supernumerary tooth



Management

Removal of cause

Use removable or fixed appliance

Active appliances incorporating labial bows can be used to close spaces – shortlabial bow, long labial bow

Crowns and prosthesis

Spacing that occurs due to microdontia

Absence / missing teeth



CROWDING

Crowding is another common manifestation of a Class I malocclusion

Occurs usually as a result of disproportion between tooth size and archlength – relative increase in tooth size or decrease in arch length

Etiology

1. Arch length- tooth size discrepancy2. Presence of supernumerary teeth

3. Prolonged retention of deciduous teeth

4. Abnormalities of tooth shape and size

5. Premature loss of deciduous teeth – Eg: early loss of 2nd deciduous molar,drifting of permanent 1st molar and resulting in 2nd premolar having lessspace to erupt – lingually placed. Similarly upper canines

6. Late lower labial segment crowing – noticed in mid to late teens. Seen inpatient who had well aligned teeth. Factors causing it:



1. Late mandibular growth

Believed that mandible may grow further forward after maxillary growth hasstopped.

As mandible grows forwards, mandibular dentition is pushed lingually, reducingarch

length and resulting in crowding

2. Reduction in intercanine width

Reduction in intercanine width noticed after age of 9. this continues into teenage

andinto adulthood at a recued rate. This responsible for late lower anterior crowding

3. Gingival fibers and occlusal forces

Pressure from transeptal fibers along with anteriorly directed occlusal forces are

believed to encourage mesial movement of posterior teeth and result in

crowding

4. Lack of approximal attrition

5. Role of 3r molars

One theory - Erupting molars produce mesial force causing crowding

The other – 3rd molar prevent dentition from moving distally in response to late mandibulargrowth

But lower anterior crowdin seen even when 3rd molars have not develo ed or have



Diagnosis

Model analysis –

Careys analysis

Arch perimeter analysis

Boltons analysis

Treatment

Most minor crowding in mixed dentition resolves spontaneously during

transition to permanent dentition

Early loss of deciduous teeth – use space maintainers

Moderate crowding in mixed dentition can be corrected by using leewayspace. Hold molars from moving forward by using lip bumper, etc

Severe crowing in mixed dentition may need Serial Extraction

Permanent dentition – Assess space required, location of crowding andpatient’s profile.

Gain space by proximal stripping, extractions, expansion, proclination,derotating and uprighting posterior teeth



ROTATIONS

Rotations are tooth movements that occur around their long axes

Two types: Mesio-lingual / disto-buccalDisto-ligual / mesio-buccal

Anterior teeth occupy less space when rotated, so require space to derotatethem

Posterior teeth occupy more space when rotated, so gain space when

derotated

Management

Space management

Removable appliances – Z spring



Thank You

ortho- treatment planning and management of class i malocclusion

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