INTRODUCTION<br /><ul><li>From the beginning of time people have noticed the prominent spaces in their dentitions.
In France, the teeth on either side of a space or gap are called ‘‘dents du bonheur’’ or ‘‘lucky teeth’’
Thus there are wide variations of perception in different cultures and ethnic background.
Maxillary midline diastemas are one of the common complaints encountered.
It has been defined as a space greater than 0.5 mm between the proximal surfaces of adjacent teeth </li></ul>3<br />
DEFINATION OF DIASTEMA<br /> A space between adjacent teeth is called a diastema.<br />DEFINATION OF MIDLINE DIASTEMA<br />Midline diastema refers to anterior midline spacing between the two central incisors.<br />4<br />
ETIOLOGY OF MIDLINE DIASTEMA<br />NORMAL DEVELOPING DENTITION<br />Physiologic median diastema/ ugly duckling stage<br />Ethnic and familial<br />Imperfect fusion of midline of premaxilla<br />2. TOOTH MATERIAL DEFICIENCY<br />Microdontia<br />Macrognathia<br />Missing lateral<br />Peg laterals<br />Extracted tooth<br />5<br />
1. NORMAL DEVELOPING DENTITION<br />7<br />a) Physiologic median diastema/ ugly duckling stage<br /><ul><li>It is a transient or self correcting malocclusion which is seen in the maxillary incisor region between 8-9 years. It is particularly seen during the eruption of the permanent canines.
As the permanent canines erupt they displace the roots of the lateral incisors mesially.
This causes a divergence of the crowns of the two central incisors causing a midline spacing.
This was described by Broadbent as the ugly duckling stage as children tend to look ugly during this phase of development. So it also known as Broadbent phenomenon.
It is a self correcting anomaly.</li></li></ul><li>8<br />
9<br />b) Ethnic and familial<br /><ul><li>Certain group of peoples, especially negroid groups exhibit median diastema as an ethnic norm.
Median diastema is seen in some families also.</li></ul>c) Imperfect fusion at the midline<br /><ul><li>Median diastema occurs due to imperfect fusion at the midline of the premaxilla.
A V-shaped or W shaped osseous septum may be associated with this condition.</li></li></ul><li>2. TOOTH MATERIAL DEFICIENCY<br />10<br />a) Microdontia<br /><ul><li>Microdontia refers to teeth that appear smaller in size compared to normal.
In this case the jaw size is normal but the size of the teeth is small which produces diastema between the teeth.
Microdontia is most frequently seen in Down’s syndrome and ectodermal dysplasia.</li></li></ul><li>11<br />b) macrognathia<br /> It is a developmental anomaly characterized by an abnormal large jaw.In this case the size of the tooth is normal but because of the increase in size of jaw, it results in diastema.<br />c) Missing lateral.<br />Due to the missing lateral there will be tooth material-arch discrepancy as a result there will be drifting of adjacent teeth.<br />d) Extracted tooth<br />This also results in tooth material-arch discrepancy which causes drifting of adjacent teeth.<br />
3. PHYSICAL IMPEDIMENT<br />12<br />a) Retained deciduous teeth.<br />This causes ectopic eruption of tooth and formation of median diastema.<br />b) Mesiodens<br />Presence of an unerupted mesiodens between the two central incisors also predispose to midline diastema.<br />
13<br />c) Abnormal labial frenum<br />The presence of a thick and fleshy labial frenum can cause a midline diastema.This type of fibrous attachment can prevent the two maxillary central incisors from approximating each other.<br />d) Midline pathology<br />Soft tissues and hard tissue pathologies such as cysts, tumors and odontomes may cause midline diastema.<br />
4. HABITS<br />14<br />a) Thumb sucking<br /><ul><li>Thumb sucking is defined as placement of the thumb or one or more fingers in various depths into the mouth.
It can cause severe proclination of the maxillary anterior teeth along with formation of diastema</li></ul>b) Tongue thrusting<br /><ul><li>This is a condition in which the tongue makes contact with any teeth anterior to the molars during swallowing.
It also causes proclination of anterior teeth along with diastema and open bite.</li></ul>c) Frenum thrusting<br /><ul><li>This habit is a self injurious habit.
If the maxillary incisors are slightly spaced apart, the child may lock his labial frenum between these teeth and permit it to remain in this position for several hours.</li></li></ul><li>15<br />
5. ARTIFICIAL CAUSES/ IATROGENIC CAUSES<br />16<br />a) Rapid maxillary expansion<br /><ul><li>Originally rapid maxillary expansion at the mid palatal suture was recommended to help meet this goal.
With rapid expansion at a rate of 0.5 to 1 mm/day 1 cm or more of expansion is obtained in 2 to 3 weeks.
A space is created at the mid-palatal suture which is filled initially by tissue fluids and hemorrhage, and the expansion is highly unstable.
The opening of the mid-palatal suture is fan-shaped or triangular with maximum opening at the incisor region and gradually diminishing toward the posterior part of the palate.
As a result there is incisor separation and a midline diastema is formed.
This diastema closes as a result of the trans-septal fibre traction.</li></ul>b) Milwaukee braces<br />
17<br />A, Bilateral constricted maxilla with upper midline shift; B, type 1 RME appliance in mouth;<br />C, end of expansion; D, correction of upper midline shift at end of retention period.<br />
6. RACIAL PREDISPOSITION<br />18<br /><ul><li>The presence of midline spacing also has a racial and familial background.
The negroid race shows the greatest incidence of midline diastema.</li></li></ul><li>DIAGNOSIS<br />19<br />a. A proper history and clinical examination should be done.<br />b. Measure the mesiodistal width of the teeth which will help in determining the tooth material-arch length discrepancies.<br />c. BLANCH TEST:- Lift the upper lip and pull in outward and look for blanching of the soft tissues lingual to and between two central incisors.<br />Presence of blanch indicates high frenal attachment as cause of midline diastema.<br />d. check for any pernicious oral habits<br />e. periapical radiograph:- presence of notching in the interdental bone is a diagnostic of a thick and fleshy frenum.<br />f. midline radiographs will help in diagnosing midline pathology.<br />
20<br />MANAGEMENT<br />REMOVAL OF CAUSE<br />ACTIVE TREATMENT<br />RETENTION<br />
1. REMOVAL OF CAUSE<br />21<br />DIASTEMA DUE TO UGLY DUCKLING STAGE<br /> No treatment required<br />DIASTEMA DUE TO IMPERFECT FUSION AT THE MIDLINE<br /> Excision of included interdental tissue between the incisors.<br /> A flap is raised interdentally and fissure bur inserted gently into the cleft. With the bur, the included tissues are removed and flap sutured.An orthodontic appliance for closure of median diastema is given during healing process.<br />
22<br />DIASTEMA DUE TO MICRODONTIA AND MACROGNATHIA<br />Such conditions can be treated by orthodontic means or by mean of jacket crowns or composite build-up.<br />Closure by jacket crown or composite build-up is the best method.<br />DIASTEMA DUE TO MISSING TEETH/EXTRACTED TOOTH<br />Space can be consolidated and replaced with implant or bridge<br />
23<br />DIASTEMA DUE TO RETAINED DECIDUOS TEETH/MESIODENS<br />The retained deciduous tooth or mesiodens should be extracted at the earliest.<br />DIASTEMA DUE TO ABNORMAL FRENUM<br />Frenectomy should be done to excise a thick fleshy frenum.<br />DIASTEMA DUE TO MIDLINE PATHOLOGY<br />Midline pathology like cysts has to be treated.<br />DIASTEMA DUE TO ABNORMAL HABITS<br />Habits should be eliminated using fixed or removable habit breakers.<br />
2. ACTIVE TREATMENT<br />24<br /> REMOVABLE APPLIANCES<br />Simple removable appliances incorporating finger springs or a split labial bow can be used.<br />Finger springs can be given distal to the two central incisors.<br />Split labial bow made of a 0.7mm hard stainless steel wire can be used.<br />In a reciprocal tooth movement the forces are applied to teeth Fare equal and opposite as a result each unit moves to a normal occlusion.<br />
25<br />A, Closure of a midline diastema can be accomplished with a removable appliance and finger springs to tip the teeth mesially. B , The 28 mil helical finger springs are activated to move the incisors together. C , The final position can be maintained with the same appliance.<br />
26<br />FIXED APPLIANCES<br /><ul><li>Fixed appliances incorporating elastics and springs bring about the most rapid correction of midline diastema.
Elastics can be stretched between the two central incisors in order to close the space.
Elastic thread or elastic chain can be used between the central incisors.
M shaped springs incorporating three helices can be inserted into the two central incisor brackets.
The spring can be activated by closing the helices.</li></li></ul><li>27<br />Closure of a diastema with a fixed appliance A. , This diastema requires closure by moving the crowns and roots of the central incisors. B , The bonded attachments and rectangular wire control the teeth in three planes of space while the elastomeric<br />chain provides the force to slide the teeth along the wire. C, immediately after space closure, the teeth are retained, preferably with, (D) a fixed lingual retainer at least until the permanent canines erupt.<br />
28<br />3. RETENTION<br /><ul><li> Midline diastema is often considered easy to treat but difficult to retain.
Retention can be achieved by:-</li></ul> Lingual bonded retainers<br />Banded retainers<br /> Hawley’s retainer<br />
29<br />NEWER APPROACH<br />ROLE OF COSMETIC RESTORATION<br /><ul><li>Esthetic composite resins are used to close midline diastema especially in adult patients.
It requires gradual composite build up on the mesial surface and stripping of the distal surface of centrals and laterals in order to achieve a natural shape and size of the teeth.</li></ul>PROSTHESIS/CROWN<br /><ul><li>Presence of peg shaped laterals or teeth with other anomalies of shape and size require prosthetic rehabilitation.
Missing teeth should be replaced with fixed or removable prosthesis.</li></li></ul><li>CONCLUSION<br />30<br /><ul><li>THUS THE TREATMENT OF MIDLINE DIASTEMA WILL IMPROVE THE ESTHETIC OF THE PERSON.
IT WILL HELP IN NORMAL ALIGNMENT OF TEETH WHICH WILL NOT ONLY CONTRIBUTE TO THE ORAL HEALTH BUT ALSO GOES A LONG WAY IN THE OVERALL WELL BEING AND PERSONALITY OF AN INDIVIDUAL.</li></li></ul><li>REFERENCES<br />31<br /><ul><li>Textbook of orthodontics by S.L. BHALAJHI 4 th edition
Textbook of orthodontics by T.D. FOSTER 3 rd edition