Space Maintenance Flashcards
During the mixed dentition, the “Golden Stage of Dentition”,
both (2) change concurrently
skeletal and dental structures
For a child with all developmental spaces, prediction goes
towards a
well aligned permanent dentition
On the other hand, any disturbance in these spaces, either
increased or decreased, can
potentially altered the outcome
Space analysis quantifies
the amount of needed space (crowding/
spacing) within the arches estimating the severity of space
discrepancy.
Space analysis requires a comparison between the
amount of space
available for the alignment of the teeth and the amount of space
required to align them adequately
Space Available and Space Required Comparison has 3 results:
(3)
- Excess
- OK
- Deficiency
Space management
* – of spaces in the arches is more common, however we should
not ignore excess space in the arch.
* Most of the time space deficiency (crowding) is divided to 3 group:
(3)
* For excess space there is not such a category. Each case will
be assessed based on its ….
Lack
1. Mild
2. Moderate
3. Severe
etiology and other factors
What is Spacing?
* Spaced dentition is characterized by …
* It is a common — problem for many patients.
* In studies related to young populations, it was found that
spacing in both arches was more common in —
* Spacing can be localized or generalized due to the —
included.
interdental spaces and lack
of contact points between the teeth.
esthetic
boys than girls.
number of teeth
Etiology
* The causes of generalized spacing
may be:
(3)
- Hereditary
- Acquired
- Functional
Hereditary causes include
(7)
- Tooth size-arch size discrepancies
- Protrusive teeth
- Congenitally missing teeth
- Macroglossia
- Supernumerary teeth
- Small teeth
- Hypertrophic frenum
Acquired problems can be
classified as:
(4)
- Pathologic conditions increasing tongue
size - Missing teeth
- Delayed eruption of permanent teeth
- Periodontal disease
Functional causes include:
(1)
- Oral habits
What can we do?
* Orthodontics plays an important role in the management of spaced
dentition, often in cooperation with other dental departments such
as oral surgery, periodontology, esthetic dentistry, and
prosthodontics.
* To achieve the most esthetic and functional result,
orthodontists must carefully evaluate the —
* — of dental casts may be useful in treatment
planning and informing the patient.
etiologic factors.
Diagnostic set-up
Why should we correct spacing?
* Spacing should be corrected because it can:
(3)
- Result in gum problems due to the lack of protection by the teeth.
- Prevent proper functioning of the teeth.
- Make the smile less attractive.
How to treat spacing?
* Three treatment options are available for generalized spacing:
(3)
- Esthetic intervention using composite resin, Veneer, Crowns,…
- Orthodontic space closure.
- Closure of anterior spaces and opening posterior spaces
After orthodontic treatment, it is frequently necessary to apply
— as these cases have a high risk of relapse
fixed retention
What is a Diastema?
(2)
- The midline diastema is a space (or gap) between the
maxillary central incisors. - The space can be a normal growth characteristic during the
primary and mixed dentition.
- Prevalence of diastema in 10 to 12 years old children:
(3)
- More in maxilla. Between central incisors.
- African American 19%
- Caucasians 8%
Diastemas may also be caused
by:
(5)
- Tooth size discrepancy
- Missing teeth
- Oversized labial frenum.
- Overjet
- Protrusion of the teeth.
Once the reason has determined. Options may
include:
(4)
- Keep the diastema.
- Orthodontic treatment.
- Composite/Porcelain veneers
- Crown and bridge work or replacement of
teeth with implants (adults only)
If oversized labial frenum is the reason, pt
may be referred for a frenectomy.
(2)
- If the frenectomy is conducted on a child, the
space may close by itself. - If it is a teenager or adult, the space may need to
be closed with braces prior to frenectomy. It is due
to scar tissue which may prevent space closure by
orthodontic forces.
In most cases, diastemas will close spontaneously as the
canines
erupt.
* Little disagreement can be found that intervention to close the
diastema should be deferred until the canines have fully erupted
Generally diastemas more than – mm require active intervention.
* Removable appliances generally close diastemas by tipping the crowns of
incisors vs fixed appliances provide better control of dental alignment
2
In the mixed dentition, caution is necessary to avoid tipping the
roots of lateral incisors distally such that they interfere with the
erupting path of the canines
There is a strong tendency toward relapse, hence a —is
nessecary.
fixed retainer
Crowding
* Crowding is the
lack of space for all the teeth to fit
normally within the jaws.
Crowding could be as the result of:
(4)
- Twisted or displaced teeth.
- Disharmony in the tooth to jaw size relationship.
- Early or late loss of primary teeth
- Improper eruption of teeth.
Etiology
* The exact cause of crowding or malocclusion in general is unknown.
* Several researchers have suggested that the problem is
(3)
hereditary and is associated with the evolutionary development
of modern humans.
* These investigators attributed the main cause of crowding to a
progressive reduction in the jaw size as compared with tooth size.
* Another author believed there are true signs of hereditary and
environmentally induced tooth-size/jaw-size discrepancy “Signs of a
True Hereditary Tooth-Size/Jaw-Size Discrepancy” and
“Environmental Factors Causing Crowding.”
Given the size of these lists, the etiology of crowding must
be considered —.
multifactorial
Crowding should be corrected because it can:
(5)
- Prevent proper cleaning of all the surfaces of
your teeth. - Promote dental decay.
- Increase the chances of gum disease.
- Prevent proper functioning of teeth.
- Make your smile less attractive
What are the Treatment Options?
* Proper management of space in the primary and mixed dentitions
can prevent unnecessary loss in arch length.
* Based on diagnosing the space problems, it could be divided to :
(3)
- Mild crowding less than 4.5 mm
- Moderate crowding 5 to 9 mm
- Severe crowding >10mm
- Mild crowding less than 4.5 mm can be resolved through;
(3)
- Preservation of the leeway space,
- Regaining space
- Limited expansion in the late mixed dentition.
- Moderate crowding 5 to 9 mm can be approached with:
(2)
- Expansion
- Some of these cases may require extraction of permanent teeth
- Severe crowding >10mm will need:
(2)
- Extraction
- Serial extraction or guidance of eruption is reserved for treatment of severe
tooth-size/arch-size discrepancies.
Bolton Analysis
* The Bolton analysis was introduced by Bolton in 1958.
* It determines the ratio of …
* It shows whether there is any tooth — discrepancy between the
upper and lower teeth.
* It is recommended for — dentition, after eruption of all
permanent teeth from 1 st molar to 1 st molar
the MD widths of the Max teeth to
Man teeth.
size
permanent
Bolton analysis determines:
(2)
- Overall ratio.
- Anterior ratio.
Calculation of Bolton Analysis
Step 1:
- Sum of Mandibular 12:
- The M-D width of all permanent teeth from 1st molar on one side to the
1st molar on the other side, is measured and summed up. (2nd and 3rd
molars are excluded) - Sum of Maxillary 12:
- The M-D width of all permanent teeth from 1st molar on one side to the
1st molar on
the other side, is measured and summed up. (2nd and 3rd molars are
excluded)
Calculation of Bolton Analysis
Step 2:
* Overall ratio:
- According to Bolton, the sum of the MD width of mandibular
teeth to maxillary teeth (12 teeth, 6-6) is 91.3%
Calculation of Bolton Analysis
Step 3:
* Interpretation: (Overall ratio)
- If the overall ratio is less than 91.3%, it indicates maxillary tooth
materials excess.
(vice versa) - The maxillary teeth are relatively too large compared to the mandibular
teeth. (vice versa)
Calculation of Bolton AnalysisStep 4:
* Anterior ratio:
- According to Bolton, the sum of the MD width of the anterior
mandibular
teeth to the anterior maxillary teeth (6 teeth, 3-3) is 77.2%.
Calculation of Bolton Analysis
Step 5:
* Interpretation: (Anterior ratio)
(2)
- If the overall ratio is less than 77.2%, it indicates maxillary tooth
materials
excess. (vice versa) - The maxillary teeth are relatively too large compared to the
mandibular teeth. (vice versa)
Calculation of Bolton Analysis
Step 6:
* Calculation in mm:
(3)
- After calculation of the Bolton ratio (Overall and Anterior), the arch with
the relatively smaller tooth material is determined and the actual
figure/value corresponding to the arch tooth size is located in the table. - The ideal value for the size of the opposing teeth is read off from the
accompanying column. - The difference between the actual value and the ideal value (according
to the table) for the relatively enlarged tooth material represents in
mm the amount of excess tooth size in the arch.
