Space Maintainer Space maintainers We recommend prompt and appropriate space management therapies (using space maintainer) to help insure optimal lifelong dental health. Space maintainers are defined as the appliances that prevent loss of arch length and which in turn guide the permanent tooth into a correct position, in the dental arch. *Importance of Baby Tooth Baby teeth aren't just for chewing. Each one also acts as a guide for the eruption of the permanent tooth that replaces it. If a baby tooth is lost too early, the permanent tooth loses its guide. It can drift or erupt into the wrong position in the mouth. Neighboring teeth also can move or tilt into the space. This means that there may not be enough space for the permanent tooth to come in. Causes of Premature Tooth Loss They can be knocked out in a fall or other accident. They may need to be extracted because of severe decay that causes infection. They may be missing at birth. Some diseases or conditions can lead to early tooth loss. *Space Management Space management is an important responsibility of the general dentist and the pedodontist. Inadequate space management can cause problems which are long lasting and severe. The premature loss of primary teeth may cause loss of arch length, resulting in crowding of the permanent dentition, impaction of permanent teeth, esthetic difficulties, malocclusion, and other problems. The "Best" Space Maintainer Natural Space Maintainer The best space maintainer is a primary tooth, as you see demonstrated in this radiograph. When nature's best space maintainer is lost prematurely, we need to intervene and maintain the space for normal development of the dental arches. Pediatric Space Management Introduction: Space Management For example, this panoramic radiograph shows the premature loss of the mandibular right second primary molar, resulting in the tipping of the first permanent molar and consequent loss of space. This is an example of space loss which could have been prevented if a space maintainer had been placed after the primary tooth was removed (earlier). Eruption times of primary teeth Upper Lower Central incisor 7.5 mths Central incisor 61/2 mths Lateral incisor 8 mths Lateral incisor 7 mths Canine 16-20 mths Canine 16-20 mths First molar 12-16 mths First molar 12-16 mths Second molar 21-30 mths Second molar 21-30 mths Eruption times of permanent teeth Upper Lower Central incisor 7 - 8 yrs Central incisor 6 - 7 yrs Lateral incisor 8 - 9 yrs Lateral incisor 7 - 8 yrs Canine 11 - 12 yrs Canine 9 - 10 First premolar 10 - 11 yrs First premolar 10 - 12 yrs Second premolar 10 - 12 Second premolar 11 - 12 yrs First molar 6 - 7 yrs Second molar 12 - 13 yrs Third molar 17 - 21 yrs yrs First molar 6 - 7 yrs Second molar 12 - 13 yrs Third molar 17 - 21 yrs Various Types Of Space Maintainers There are numerous types of space maintainers. They range from the very simple to those with numerous bands and wires. They can be constructed differently and used in different parts of the mouth. Some even have parts extending into the tissue. Examples Of Various Types Of Space Maintainers Variations on Space Maintainer There are numerous variations on these basic themes. For example, some space maintainers are used for missing anterior teeth and some are used to preserve space for posterior unerupted teeth. Classification Of Space Maintainers There are numerous types and subtypes of space maintainers is to start by classifying them broadly into four categories. They can be fixed or removable, and they can be unilateral or bilateral. Removable and Fixed • A removable space maintainer, of course, can be removed. • A fixed space maintainer is fixed (i.e., held) to a tooth or to more than one tooth. Fixation usually is done by cementing the space maintenance appliance in place. Unilateral and Bilateral • Fixed space maintainers can be unilateral or bilateral. • Unilateral space maintainers are fixed to one side of the mouth and • Bilateral space maintainers are fixed to both sides of the mouth. Indications: Premature loss of primary molar The premature loss of primary molars may require the placement of a space maintainer to prevent the migration of the adjacent teeth, depending upon the teeth present and the arch length. Premature loss of primary canine When loss of primary canine occurs, the dental arch midline may be compromised and the arch length also may be reduced. The premature loss of primary canines may therefore require the placement of a space maintaining appliance to prevent midline deviation and/or loss of arch length, perimeter and/or circumference. Premature loss of primary incisors The premature loss of primary incisors does not usually require the placement of a dental appliance for the maintenance of space because mesial movement of the adjacent teeth is not generally expected. *Contraindications : A space maintainer is usually not necessary if there is a sufficient amount of space present to allow for eruption of permanent tooth/teeth. A space maintainer may not be recommended if severe crowding exists, such that space maintenance is of minimal effect and subsequent orthodontic intervention is indicated. A space maintainer may not be necessary if the succedaneous tooth will be erupting soon. Types of space Maintainers The treatment modalities may include, but are not necessarily limited to the following types of appliances Fixed appliances Band and Loop/Crown and Loop Distal Shoe Lower Lingual Arch (For mandible) Nance Appliance (For Maxilla) Removable appliances Hawley appliance/Removable dentures In case of unilateral loss Fixed appliances Band and Loop/Crown and Loop Distal Shoe Removable appliances Hawley appliance/Removable dentures In case of bilateral loss For maxilla : Nance palatal holding arch. Bilaterally placed band and loop space maintainers For mandible : Lingual arch. Bilaterally placed band and loop space maintainers Space maintenance for premature loss of deciduous first molar In case of unilateral loss : Band and loop-nonfunctional passive space maintainer or Crown and loop space maintainer. Deciduous second molar is used for abutment tooth. Indications For Space Maintenance Therapy A space maintainer is indicated to prevent mesial movement of the second primary molar. A band and loop space maintainer is the best choice. It is especially important to start space maintenance therapy prior to the eruption phase of the first permanent molar, since the force of eruption of the permanent molar will exert a lot of pressure to push the second primary molar forward. The eruption phase of the 1st permanent molar is the time of greatest force exerted against the primary molar. Fixed Unilateral Appliance This photograph shows an example of a fixed unilateral appliance on the maxillary left side for a seven year-old patient. The photograph demonstrates the appliance after cementation. This appliance is referred to as a band and loop space maintainer and is a favorite among many clinicians. Band And Loop Space Maintainer Band and loop space maintainer Band and Loop space maintainer Indication : Loss of first primary molar tooth. Advantage : Easy of fabrication for the clinician Requires less chair time Easy of maintenance for the patient. Disadvantage Opposing tooth may over-erupted. Nonfunctional passive space maintainer, so It does not helps in mastication. Steps of Construction of Space Maintainer Once a decision is made regarding what type of appliance is needed and how it is to be used, the next phase of the space maintenance protocol involves creating the appliance. Four steps are involved in fixed appliance therapy: 1. Fitting the bands, 2. Impression taking, 3. Appliance fabrication, 4. Cementation. In the case of removable appliances, impression taking is the first step since bands will not be used. Selecting And Fitting Bands The first step in the process of appliance fabrication is selecting and fitting the bands accomplished by estimating the proper size of band needed. A trial and error method is used by most clinicians when selecting bands for an appliance. Selecting And Fitting Bands The estimation is done by examining the tooth which will be banded and selecting a band from the box of bands which appears to be the appropriate size for that tooth. Appliance Construction - Fitting The Bands Occasionally we discover that the contacts between the teeth are so tight that separating elastics are necessary before the bands can be placed. Selecting And Fitting Bands The separating elastic is situated between the teeth where the band will be placed. One of the easiest methods of elastic placement is to use two threads of dental floss in order to hold the elastic. Next, gently "saw" the elastic between the teeth. Ideally, the elastic can be placed a few days before the band fitting appointment. If that were not possible, elastics could be placed at the same appointment. When both steps are planned for the same appointment, better separation will result if at least fifteen or twenty minutes is scheduled between elastic placement and the band try-in. Selecting And Fitting Bands The first step in the placement process is carrying the band to the tooth and placing it on the tooth with finger pressure. Further placement of the band can be done by pushing with a tongue depressor or the handle of a band seater. The patient can be asked to bite on the tongue depressor or handle of the band seater to push the band further apically. Selecting And Fitting Bands Some clinicians use a tongue depressor to aid in pushing the band down over the tooth. You can ask the patient to bite gently on the tongue depressor and the band is pushed down. HELPFUL HINT: As shown in the photograph, sometimes a tongue depressor which has been broken in half can be used more effectively than an unbroken tongue depressor, since the broken tongue depressor is smaller and easier for the child to bite on. Selecting And Fitting Bands The advantage of using a tongue depressor is that the band is almost never crushed during placement. Selecting And Fitting Bands The handle of a band seater also is a convenient instrument to use to push the band into place. If the band is too large, it will be too loose a fit. If it is too small, the band will not go down over the tooth. We usually consider a nicely adapted band to be one that is placed on the tooth with some resistance and one which cannot be lifted off with finger pressure. We remove and place various bands until we obtain one which has a good fit. Usually a band seater is used for further adaptation after initial placement. Please note how the band seater is placed on the tooth prior to having the patient bite down on the seater. Band seaters come in circular and triangular shapes. CAUTION: If you use the triangular seater, it is important not to place it next to the band in such a way that the patient can inadvertently drive the triangular piece into the cusp of the tooth. This may fracture the cusp. A Nicely Fitted And Adapted Band Band Pusher A band pusher may be used for the final step in adaptation of the band. It is used to push the band against the tooth if a space remains between the band and the tooth. Tightly placed and well adapted bands are desired, so that washout of the cement is less likely to occur. Compound Impression With Band In Place Fabricating The Appliance Nicely Cemented Band (Using Glass Ionomer Cement) Time To Remove Space Maintainer Time To Remove Space Maintainer Time To Remove Space Maintainer Band Removal Pliers. Note the use of band removal pliers. These are used during the placement and fitting process to remove bands. Of course, the same band removers are used to remove space maintainers when necessary in other clinical situations, for example when they are no longer needed due to eruption of permanent teeth Crown and loop space maintainer Indication : Loss of First primary molar with significant loss of abutment tooth. Advantage : Easy of fabrication for the clinician Easy of maintenance for the patient. Disadvantage : More difficult to fabricate than band and loop Crown and loop space maintainer Crown And Loop Space Maintainer Fixed Unilateral Appliance The photograph presents a variation on the band and loop space maintainer; a mandibular left crown and loop space maintainer is shown. Note how the stainless steel wire is soldered to the stainless steel crown and the wire is bent so that it is adapted closely to the tissue. The crown and loop space maintainer is a type of fixed unilateral space maintainer where stainless steel crown therapy was necessary on the abutment tooth. Fixed Bilateral Space Maintenance: Space Maintainers: Types Of Space Maintainers The photograph demonstrates another variation on the bilateral use of fixed unilateral space maintainers. In this case, a fixed unilateral band and loop space maintainer was used on one side and a fixed unilateral crown and loop space maintainer was used on the other side. Crown and loop space maintainers can be used when a stainless steel crown is needed on a tooth which also is an abutment for a space maintainer. However, often band and loop space maintainers are used over stainless steel crowns. The rationale for using a band and loop space maintainer over a stainless steel crown is that if the band and loop appliance is no longer needed or if it fails, replacing the stainless steel crown will not also be necessary. Nance palatal holding arch Indication : Bilateral loss of upper first primary molar. Bilateral loss of upper second primary molar. Advantage : Maintain the tooth space and leeway space Allows growth transversely in the inter canine area. Disadvantage : Palatal acrylic button may cause food accumulation leading to an inflammatory soft tissue response in the palate. Nance palatal holding arch Nance palatal holding arch Maxillary Fixed Bilateral Space Maintainer (Nance Appliance) Maxillary Fixed Bilateral Space Maintainer (Nance Appliance) Maintenance The photograph shows a maxillary fixed bilateral space maintainer. This type of space maintainer also is known as a Nance Holding Arch or a Nance Appliance. Note the small acrylic button which will rest against the palatal tissue with this appliance. Some clinicians object to the button since it can create tissue irritation. Therefore, it is important that patients and parents be instructed to make sure that the patient meticulously flosses under the acrylic button. The Nance Holding Arch is used in situations where premature bilateral loss of maxillary primary teeth has occurred. Bilateral Band And Loop Space Maintenance This photograph shows two band and loop space maintainers, an example of the bilateral use of fixed unilateral band and loop space maintainers. These are very common types of unilateral space maintainers, and they often are used bilaterally. Lower lingual arch Indication : Bilateral loss of lower second primary molar Bilateral loss of first lower primary molar Advantage Maintain the tooth space and leeway space. Disadvantage First permanent molars may be susceptible to decalcification, may be prone to breakage unless the patient is well informed on maintenance. ***Mandibular Fixed Bilateral Space Maintainer (Lower Holding Arch) Lingual arch space maintainers: Fixed Bilateral Space Maintainer This photograph shows an example of a fixed bilateral space maintainer. The patient is four years of age. The appliance is cemented on the two second primary molars. Fixed bilateral space maintainers on the mandibular arch often are called lingual arch space maintainers. Mandibular fixed bilateral space appliances generally are preferred by clinicians over removable space maintainers. Fixed appliances are easier to maintain and they are less likely to be removed, damaged, or lost by the child. Lingual arch space maintainers: Fixed Bilateral Space Maintainer Another lingual arch appliance for mandibular bilateral space maintenance is shown here. In this case, the appliance is attached to permanent teeth. The mandibular lingual arch space maintainer is used very commonly in the primary dentition and the mixed dentition, where bands can be cemented to primary or permanent molars respectively. This is one of the most ubiquitously used space maintainers. It is even used on occasion in the permanent dentition when bicuspids are missing and maintaining space is necessary prior to orthodontic and/or prosthetic therapy. Mandibular Removable Bilateral Space Maintainer A mandibular removable bilateral space maintainer is shown on a six year-old. This youngster prematurely lost the mandibular right and left first and second primary molars. The disadvantages of a removable appliance are that it may not be worn by the patient and it is more susceptible to breakage or loss by the patient. To reiterate, most clinicians prefer to place fixed space maintainers if possible. Prosthetics For Maxillary Anterior Teeth The appliance demonstrated in this photograph is used to replace missing maxillary anterior primary teeth (it is an example of a type of maxillary anterior prosthesis). Mandibular Removable Bilateral Space Maintainer The same mandibular removable bilateral space maintainer is shown outside of the mouth. Note the wire attachments designed for the purpose of improved appliance retention. Mandibular Removable Bilateral Space Maintainer Space maintenance for premature loss of deciduous second molars In case of unilateral loss Band and loop space maintainer. In case of bilateral loss For maxilla : Nance palatal holding arch. Bilateral band and loops are indicated For mandible Lower lingual arch. Bilateral band and loops are indicated Indications For Space Maintenance Therapy This is a radiograph of a similar situation showing the missing mandibular right second primary molar. Space maintenance on premature loss of deciduous second molars but before the eruption permanent first molars. Methods of space maintenance in such condition are Distal shoe Advantage : Maintain the second primary molar space. Disadvantage : Difficult to fabrication. It is contraindicated in some medically compromised patients eg. Blood dyscrasias Congenital heart defects Diabetes mellitus Poor oral hygiene. Distal Shoe Space Maintenance This appliance is called a distal shoe space maintainer or a distal extension space maintainer. It is used to prevent first permanent molars from moving mesially with the premature loss of second primary molars. The example shown is a crown with a distal extension segment soldered to the crown. The distal segment is extended into the tissue against the unerupted first permanent molar. The distal extension, also called a distal shoe, is used when the second primary molars are lost prior to the eruption of the first permanent molars (i.e., very premature loss). Distal shoe space maintainer Indications For Space Maintenance Therapy This photograph demonstrates stainless steel crowns on the cuspid and the first primary molar, with a distal bar extending into the tissue, thereby preventing the first permanent molar from tipping mesially over the underlying premolar. Maintenance Therapy This radiograph shows the placement of a distal shoe space maintainer extending to the mesial surface of the unerupted first permanent molar. The distal shoe space maintainer is intended to prevent the first permanent molar from erupting in a tipping manner over the underlying premolar. Indications For Space Maintenance Therapy This is an example of a distal shoe space maintainer which has been successful in directing the eruption of the first permanent molar. However, since the first permanent molar has now erupted, the existing distal shoe appliance should be removed and a band and loop space maintainer can be placed. Time To Replace The Distal Shoe (With A Band And Loop) Indications For Space Maintenance Therapy This photograph shows the band and loop space maintainer which has been used to replace the distal shoe appliance. It is advantageous to replace the distal shoe, which extends under the tissue and is less hygienic than a band and loop space maintainer. Space maintenance for premature loss of deciduous incisor The premature loss of primary incisors does not usually require the placement of a dental appliance for the maintenance of space because mesial movement of the adjacent teeth is not generally expected. Appliance may require use removable partial denture. Hawley appliance/Removable acrylic Indication : When multiple teeth are lost and space maintenance and mastication are of concern. Advantage : Can maintain space as well as aid in mastication. Helps in speech development. Disadvantage : Susceptible to fracture or loss. Discomfort for the child. Maxillary Removable Bilateral Space Maintainer Removable Unilateral Space Maintainer (NOT USED) WE FEEL REMOVABLE UNILATERAL SPACE MAINTAINERS ARE DANGEROUS These are examples of dangerous space maintainers. They are removable unilateral space maintainers. We believe removable unilateral space maintainers should not be used. They are too small and present swallowing and choking dangers for children. For safety reasons, we recommend not to use a removable unilateral space maintainer. If they are dislodged, they are so small that they can become a swallowing or choking danger. Conclusion Space maintainers help “hold space” for permanent teeth. The child may need one if he or she loses a baby tooth prematurely, before the permanent tooth is ready to erupt. If a primary tooth is lost too early, adult teeth can erupt into the empty space instead of where they should be. When more adult teeth are ready to come into the mouth, there may not be enough room for them because of the lost space. To prevent this from happening, the dentist may recommend a space maintainer to hold open the space left by the missing tooth.