For displacement injuries and exarticulations these splints have the advantage of
allowing a more accurate reduction of the injury by gentle forces (727HFig. 12.34(a and
b)).
FOIL/CEMENT SPLINT
A temporary splint made of soft metal (cooking foil) and cemented with quick setting
zinc oxide-eugenol cement is an effective temporary measure either during the night
when it is difficult to fit a composite-wire splint as a single-handed operator or while
awaiting construction of a laboratory made splint.
Technique:
- Cut metal to size, long enough to extend over two or three teeth on each side of the
injured tooth and wide enough to extend over the incisal edges and 3-4 mm over the
labial and palatal gingiva. - Place foil over teeth and mould it over labial and palatal surfaces. Remove any
excess. - Cement the foil to the teeth with quick setting zinc oxide-eugenol cement.
LABORATORY SPLINTS
(1) acrylic;
(2) thermoplastic.
These are used where it is impossible to make a satisfactory splint by the direct
method, for example, a 7-8 year old with traumatized maxillary incisors, unerupted
lateral incisors, and either carious or absent primary canines. Both methods require
alginate impressions and very loose teeth may need to be supported by wax, metal
foil, or wire ligature so they are not removed with the impression.
- Acrylic. There is full palatal coverage and the acrylic is extended over the incisal
edges for 2-3 mm of the labial surfaces of the anterior teeth. The occlusal surfaces of
the posterior teeth should be covered to prevent any occlusal contact in the anterior
region. This also aids retention and Adams Cribs may not be required. The splint
should be removed for cleaning after meals and at bedtime. - Thermoplastic. The splint is constructed from polyvinylacetate-polyethylene
(PVAC-PE) copolymer in the same way as a mouthguard with extension onto the
mucosa. It should be removed like the acrylic splint after meals and at bedtime.
However, with more severely loosened teeth it could be retained at night.
Both forms of laboratory splint allow functional movement and therefore promote
normal periodontal healing. They are not suitable for root fractures as they
compromise oral hygiene.