This section is from the book "Dental Medicine. A Manual Of Dental Materia Medica And Therapeutics", by Ferdinand J. S. Gorgas. Also available from Amazon: Dental Medicine.
The advantage of rest and immobility cannot be overestimated, for a simple lesion, if subjected to constant mobility, may become one of a much greater character, destructive inflammation often being provoked by friction and undue motion. An example is furnished in the case of periodontitis, where a cap or partial interdental splint made of modeling composition or gutta percha, or vulcanized rubber, will protect the affected tooth from irritation, and materially assist the remedial measures; also strips of adhesive plaster, collodion, etc., will insure immobility in certain cases where such appliances are indicated, as undue motion retards and prevents the process of healing.
Position is also to be considered as a means for relieving the irritation and pain, so that no provocation may exist for subsequent inflammation. The best position should be selected for the affected part, which will favor the return of venous blood and retard the arterial current; hence, an elevated position will tend to prevent passive hyperaemia. A favorable position will also secure muscular relaxation, and prevent the involuntary spasmodic action, which may result from muscular tension. The administration of an anaesthetic to secure muscular relaxation, in the case of certain injuries, as in fracture or dislocation of the jaw, is often resorted to as a measure against spasmodic contraction, and also to reduce the excessive vascular reaction.
Cold, when outwardly applied as a depressor to the inflamed part, reduces the excitement and irritability. The application of the spray of absolute ether, or of rhigolene, will often prove serviceable in the early stage of periodontitis. Cold, whenever moderately applied, is tonic and invigorating, and besides evaporating applications, ice may be employed; but such local measures to maintain a low temperature must be renewed at short intervals. Cold, when locally applied, causes the capillaries to contract, thus diminishing the afflux of blood to the affected tissue. The persistent application of cold, however, may cause gangrene; but the employment of the ether or rhigolene spray is attended with less danger in this respect than that of ice applications. A granulating surface, on the other hand, develops better in a warm temperature.