Pedo sheet # 5 - Anas Almo3'rabe

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Pedo sheet # 5 - Anas Almo3'rabe

Post by Shadi Jarrar on 16/3/2012, 7:31 pm

Shadi Jarrar
مشرف عام

عدد المساهمات : 997
النشاط : 12
تاريخ التسجيل : 2009-08-28
العمر : 27
الموقع : Amman-Jordan

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Re: Pedo sheet # 5 - Anas Almo3'rabe

Post by Shadi Jarrar on 17/3/2012, 4:28 am

*we'll talk today about – Early loss of primary teeth & Space maintenance:
- effects of the early loss of primary teeth
- prevention of space loss
- types of space maintainers
- & indications for use

• There are forces on the primary teeth from all directions (mesially, distally, occlusaly, even gingivally –underling tooth-), if a force was removed from any direction this will lead to imbalance. So if we extract a tooth we'll have over eruption of the opposing one, & if we extract the tooth mesial or distal to this tooth this will cause drifting towards the missing tooth. So if we extract a tooth we'll end up with drifting of teeth & development of space problems, this can result in loss of the arch length. As an example, early extraction of the lower E will lead to mesial drift of the lower 6, distal drift of the D, as a result; we'll end up with loss of the arch length & crowding in the permanent dentition. (i.e. the lower 5 –the last tooth to erupt in the lower jaw- won't find a place to erupt, most of the time it will stay impacted or will erupt buccaly or lingually casing crowding of teeth).
**as a conclusion, early loss of primary teeth can result in →→ loss of the arch length, crowding in the permanent teeth. Sometimes, it can cause esthetics difficulties, like shifting in the midline –it's not common-

• What's the best Space Maintainer??
-it's the primary tooth itself , a well-maintained primary tooth is better than any appliance we construct.

• Planning factors ( what do you think of before deciding on a space maintainer??):
 Time elapsed since loss (when was the tooth extracted)
 Dental age of the patient (we have to take an x-ray before deciding on a space maintainer, we don't depend on the chronological age alone)
 Amount of bone covering the permanent tooth (we have to take an x-ray)
 Eruption of neighboring teeth
 If we have Delayed or deviant eruption
 Oral hygiene (we have to consider the oral hygiene of the patient)
 Time Elapsed:
 space closure usually happens on the 1st 6 months, then stabilization of the dentition will occur, so if we have an extraction a couple of years ago, most of the time we won't need a space maintainer. Either, we use a space re-gainer or we just have to accept the situation as it is.
 Loss of space can occur within days, especially in the upper jaw; that’s why we try to fabricate the appliance before extraction, we choose the band, take an impression, then we can do the extraction, a week later we can cement the appliance. If the condition wasn't acute we can do the extraction when the appliance is ready, we just wait for 10 minutes after the extraction till homeostasis & then cement the appliance.
 Most Space Maintainer Protocol involves two appointments: the 1st appointment for extraction & impression making, the 2nd for placement & cementation of the appliance.
 Dental Age:
 Chronological age not as important as the dental age. As an example, if we have a 9-year-old boy, you'll expect that the 4's especially the lowers are about to erupt, if the D's were extracted at that age most of the time we don't need a space maintainer, but we have to take an x-ray to be sure of the dental age, so that if the dental age was delayed we might need a space maintainer. the chronological age can act as a guide but it's not as important as the dental age.
 Permanent teeth erupt when 1/2-3/4 of root development has completed.
 Eruption of underlying premolars is:
o Delayed: if loss of primary molars occurs early, as an example, if we have a
three-year-old child with early childhood caries we put him under GA and extract all the D's, then this will cause delay in the eruption of the 4's. also if we extract the A's or the B's this will delay the eruption of the permanent incisors.
o Accelerated: if loss of primary molars occurs late close to the age of eruption, as an example, if we extract the D's in a seven-year-old child this will accelerate the eruption of the 4's.
o This effect decreases with increasing age.. at extremes of age the most delay will be in primary molars, so if we get to an 8-year old it won't accelerate it but it'll help the eruption!!

 Amount of Bone:
 It's very important, before we decide to put a Space maintainer to take an x-ray to the involved area, so that if bone is present around the permanent tooth we use a space maintainer because the tooth will take time to go through the bone & erupt.
 They estimate that a 1mm of bone on a bitewing x-ray will need about 4-5 months to erupt. However, it's not reliable as a measure. So we put a space maintainer even for a short period of time.
 What happens often is that bone is destroyed due to chronic infection of the primary tooth (molar), we take an x-ray & there is no bone overlying the underlying tooth (premolar). If bone is destroyed due to infection predictions based on root development aren't accurate (i.e. you can get a 5 erupting in a 7-year-old child without any root cause there's no bone overlying it). In this case we don't need a space maintainer.
 Eruption is usually accelerated when bone is lost.

 Eruption of neighboring teeth:
 The sequence of eruption is very important in directing us whether we need a space maintainer or not.

 Delayed or deviant eruption:
 active eruption creates increase in space loss, as an example, if we took the E out during the eruption of the 6 in a 5-6 year-old child, we'll notice that the 6 will drift completely in the place of the 5. So we try to postpone the extraction of the E especially in this critical period (for example we do pulpotomy).
 Sometimes you take an x-ray & you get altered eruption path of the permanent tooth, as an example, distal eruption of the 5, we take an x-ray & notice that the crown of the 5 is directed distally, it will cause delayed eruption, so we consider the extraction of the primary tooth & insertion of a space maintainer.
 Oral hygiene:
 It's very critical, the child should be motivated to clean the appliance
 So if the oral hygiene is poor, motivate then re access, if the child or the parents still aren't motivated or regular attender then space maintainer is contraindicated
 Oral hygiene is more important than maintaining the space

• Types of space maintainers:
 Fixed or removable
 unilateral or bilateral
 maxillary or mandibular.

 Fixed space maintainers:
o Advantages:
 Patient compliance not required, appliance is worn continuously
 Provides sufficient space for permanent tooth to erupt
o Disadvantages:
 Banded tooth is more susceptible to caries, so if the patient isn't a regular attender, decementation will occur, food will accumulate around the band causing caries to the patient.
 Opposing tooth may over erupt
 Doesn't restore function
 Doesn't replace the missing tooth
-anyway this is what we'll be using in the clinics.

 Removable space maintainers:
o Advantages:
 Provides functional space maintenance, cause it replaces the missing tooth, it's just like the partial dentures.
 Opposing teeth prevented from over eruption
o Disadvantages:
 Compliance may be a problem, appliance not worn, because we're dealing with children
 Frequent incidences of breakage, & added cost for the parents
 Appliance may be lost when removed

** Examples of Space Maintainers:
 Fiwed bilateral lingual arch space maintainer:
 Here the 6's are banded & there's a wire resting on the lingual surface of the lower anteriors, the lower anteriors should be permanent, cause the permanent teeth may later erupt lingual to the lingual arch so if we make the appliance on the primary anteriors then after the eruption of the permanent we'll have to remake the appliance again, also we can't rest the wire on the primary anteriors as they may become mobile.

 Indications:
o Lower jaw
o Bilateral loss of teeth
o Unilateral loss of more than one unit in a quadrent, as an example if we have the D & E extracted from one side & the other side is intact, we can't use a unilateral appliance cause the span is long so that distortion or breakage to the appliance may occur.
o Loss of primary canines

The band can bind either on primary or permanent teeth

 Band & loop space maintainer:
 It's a band on the 6 or the E & there's a loop extending to the 1st mesial tooth after the space
 One tooth is missing here, & if the permanent tooth (premolar) wants to erupt it can erupt there's enough space
 Indications: loss of one unit in a quadrant.
 Reverse band & loop, if the 6 is partially erupted then we band the D, so the loop is moving distally.
 Sometimes we can use bilateral band & loop

This can be used unilaterally per unit
These are very common types of unilateral space maintainers, and they often are used bilaterally.

 Crown & loop:
 We take an impression before we cement the crown & send it to the technician, he prepares the loop part & weld it to the crown, then we cement the crown & loop together, so we end up restoring the tooth & having a space maintainer
 It's better to cement the crown on its own (we put a band & take impression to prepare the loop) because the weakest point on the crown & loop appliance is the welding point, it may separate or fracture & in this case we have to decement the crown from the tooth which is very difficult. So what we do is that we cement the crown & then put a band on the crown, take an impression, send it to the technician, finally we cement the band & lope over the crown itself.

 Indication:
o Loss of one unit in a quadrant when the abutment tooth is restored with a SS crown.

 Maxillary fixed space maintainers:
1. Nance Appliance:
 Here the 6's are banded & we have a small acrylic button, which will rest against the palatal tissue
 It's a very good space maintainer, prevents the movement & the rotation of the 6's
 The problem here is the acrylic button, although it prevents the movement of 6's, it can cause food impaction beneath it causing tissue irritation. So the patient should use a Dental Floss to clean it, since the patients are children they won't be that motivated to clean beneath it.

2. Trans palatal arch:(TPA)
 It's cleaner appliance to use than the Nance appliance
 Here we're just depending on the rigidity of the wire to prevent the 6's from moving foreword
 There's a wire that traverses the palate directly without touching it
 The problem here is that slight rotation or loss of space could happen when you compare it to the Nance
 It may allow the tooth to move & tip mesially resulting in space loss
 We would rather to use the TPA over the Nance because of the oral hygiene, even though the Nance is better as a space maintainer.

 Maxillary removable bilateral space maintainer:
 Just Like the partial denture
 Indication: if we have a loss of multiple teeth usually bilaterally
 We probably won't be using them cause we're dealing with children; they won't wear it

 Removable unilateral space maintainers:
 We have one tooth that is missing
 The child won't wear it
 Shouldn't be used; they are so small & present swallowing & chocking dangers for children

*** what are the types of Space maintainers that we use with every early lost tooth??
• Early loss of Primary Incisors:
 You need to know that the early loss of A's & B's doesn't cause space loss, so If the canines & molars are present there's no space loss (very little space loss)
 The parents would ask for esthetics & function
 A prosthesis (removable) may be constructed if desired: space maintenance is questionable, so it’s mainly for esthetics & development of speech
 We can use a fixed appliance, we band the E's with a 0.9mm wire & the teeth are fixed to the wire, we use it if the patient is less than 3 years or he has a questionable cooperation
 Even the appliances are available, we don't use them on children, cause they may render the growth of the maxilla, so we tell the parents that there's no need to put anything, once he enter the school his school mates will be started to change their teeth, also the development of speech won't be affected that much, so it's not a problem
 If we have a loss of permanent incisors, would we use a space maintainer or not??...yes, it requires an immediate space maintainer so that no midline shifting would occur
• Early loss of primary canines: محمد جبر
 Bilateral loss usually causes: lingual collapse, loss of arch length, increased overbite & increased overjet
 Unilateral loss usually causes: midline shift in addition to the above.
 The appliance of choice is the lingual arch

• loss of primary 1st molar:
 Unilateral loss we use a band & loop
 Bilateral loss we use bilateral band & loop
 No lingual arch until the permanent incisors have erupted
 If the D's have extracted in the mixed dentition & the 6's have erupted, then if we have unilateral loss we use a band & loop, bilateral loss we can use bilateral band & loop in the upper & lower arch, lingual arch in the lower arch & TPA or Nance in the upper arch.

• Loss of primary 2nd molar:
 Unilateral loss we use band & loop (we band the 6 & the loop part is resting against the D, or we use reverse band & loop if the 6 is partially erupted)
 We have to consider the eruption sequence, i.e. in the lower jaw the 4 will erupt before the 5, so if we use a band & loop we might loss the D here before the 5 erupts, & in this case we have to make a new appliance or we can use the lingual arch from the beginning (if the 6 have erupted).
 If we have bilateral loss in the upper jaw we can use TPA, Nance or a removable appliance

 Distal Shoe Space Maintainer:
 Indication: early loss of the E prior to the 6 eruption which is a critical period
 There's a distal segment extended into the tissues against the unerupted 6; to guide its eruption
 Disadvantages:
o Difficult to construct (we need to take a periapical x-ray to determine the amount of bone)
o Removed & replaced with band & loop after rhe eruption of the 6 (there's another way, we flip the distal part occlusally so that it will act as a space maintainer against the partially erupted 6 (prevents the 6 from moving mesially), & if there is any interference with occlusion we just cut it.
o Contraindicated in medically compromised patients such as patients with congenital heart defects.
 The only alternative is that we try to keep the E in its place as long as possible by doing pulpectomy (>5 years old) until the 6 eruption, it's not very successful (50% success rate), explain the probability of failure to the parents
 We have to explain the necessity to replace the distal shoe with band & loop or lingual arch After the eruption of the 6 to the parents

***How to make a Space Maintainer??
*we have two methods:
A. Chairside fabricated space maintainers: don't require sending to the lab:
 Orthodontic wires
 Band & loop
 Fiber reinforced composite resin

 Orthodontic wires:
 Very simple, placed in one appointment
 It’s suitable as an interim space maintainer, in the remote areas where there are no space maintainers we can use it as a temporary solution
 Wire contoured to fit the space of the missing tooth without interfering with occlusion
 Cemented with composite resin

 Band & loop:
 Denovo company
 Placed in one appointment, we choose the right size of the loop or the crown, & the length of the loop, then we do crimping & finally cementation
 No need for impressions or models
 No welding or wire bending required
 it eliminates the lab fees
 it eliminates time consuming

 fiber reinforced composite resin:
 FRCRs have been used in, removable prosthodontics, fixed partial dentures, periodontal splints, orthodontic treatment (as a retention splint) & space maintenance.
 Two types:

o Glass fiber reinforced composite resins (everstick, stick tech):
 Composed of densely packed silanated E glass fibers in a light curing gel matrix
 Advantages:
 no need for a cast model
 no second visit
 easy to apply, we cut as the length that we want & then cement it with composite
 no metal allergy
 it's easy to clean
 esthetically designed, tooth colored
 disadvantages:
 breaks easily
 poor retention
 over the 23 space maintainers evaluated, 13 failed & 10 were successful. The clinical success rate was found to be 43% over 12 months.

o Polyethylene fiber reinforced composites (Ribbond):
 Very strong, are comparable to stainless steel in terms of physical strength & biofilm formation
 They may be a clinically acceptable & an expedient alternative to the conventional band & loop appliance.

B. Two-visit Space Maintainers (traditional fixed SM)
Steps of fabrication :
 Band selection
 Band adaptation
 Alginate impression, with the bands inside the patient mouth
 Stone cast
 appliance design, send it to the technician
 wire bending & soldering
 try the appliance, if good then cement it
• band selection:
 we choose the abutment tooth
 choose the right band size, select the smallest band that will fit over the height of contour of the tooth
• band adaptation:
 first we seat the band using digital pressure, & then we utilize a band seater with the (lead peg!) on the occlusal margin of the band to fully seat the band
 then we do adaptation around the contour of the tooth & its morphology
 properties of properly adapted molar band:
o occlusal margin of the band is apical to the proximal ridges
o gingival margin of the band is in the gingival sulcus
o band is snugly adapted to the tooth's surface
• alginate impression:
 in band & loop we just take a half-arch impression, we take the impression with the band inside the patient mouth
 stabilize the band with sticky wax
 check that the occlusal margin of the band is clearly reproduced
 remove the band from the patient mouth & orient it in the proper direction (on the alginate impression itself after we've took it)
• pour impression:
 use the white plaster
 if you're going to abrade the cast, use stone, cause in some cases we take the impression before extraction the tooth, then we have to cut it from the cast
 prepare flat base so that the cast wouldn't rock during the fabrication of the appliance
• design of band & loop space maintainer:
 space maintainer contacts the tooth mesial to the space in the middle third
 the anterior curve of the loop is shaped to approximate the distal surface of the mesial tooth & to match its width (the dr' said the abutment tooth!)
 the loop contacts the middle part of the band
 the wire should be above the gingiva at the point of contact with the abutment tooth
 we can use a rest occlusally on the abutment to prevent gingival drift or trauma
 proper contour, horizontal part of the wire at the junction between the middle & occlusal third of the band!!
 The central portion of the loop is shaped wide enough to allow the full eruption of the permanent tooth
 The loop should be contoured to follow the edentulous ridge, but 1mm above the tissues

• Cementation of space maintainer:
 Appliance is fitted & adjusted if necessary
 Cement using Glass Ionomor cement or Polycarboxylate cement
 Excess cement is removed
 Instructions given to patient & parents

• Instructions following insertion:
 avoid hard or sticky foods (coffee, hard candy, gum, popcorn …etc)
 teeth should be brushed after each meal & the teeth with band around them should be cleaned especially well
 a 3-monthly review is appropriate, we insist to see the patient every 3months because there is a decementation possibility of the appliance
 inform the patient not to try to bend the wire for any reason with finger or tongue
 inform the patient to come in for an emergency appointment if the bands come loose or if the space maintainer is damaged in any way

** it's usually safe to remove the space maintainer after the permanent tooth has erupted

Anas Al-Moghrabi
Pedo. Sheet #5

Shadi Jarrar
مشرف عام

عدد المساهمات : 997
النشاط : 12
تاريخ التسجيل : 2009-08-28
العمر : 27
الموقع : Amman-Jordan

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Re: Pedo sheet # 5 - Anas Almo3'rabe

Post by Sura on 28/3/2012, 1:22 am


عدد المساهمات : 484
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تاريخ التسجيل : 2010-09-29

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Re: Pedo sheet # 5 - Anas Almo3'rabe

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