Temporary closure of root canals
To prevent recurrent infection of the treated root canal, and to treat destructive forms of periodontitis in a more individual and reasonable way, a number of nonhardening paste types are used for temporary closure of root canals.
These temporary materials include the pastes based on calcium hydroxide, hydroxylapatite, antibiotics and corticosteroids, metronidazole, mixture of prolong-action antiseptics (thymol, creosote, camphor, menthol, iodoform etc.).
Calcium hydroxide is tasteless white powder with strongly alkaline medium (pH 12,5). Bacteria do not survive if pH index exceeds 9,5. Antiseptic action of calcium hydroxide continues until the pH index in the root canal reaches 8,0. This medicine is used in the powder or paste form. Pure powder Ca(OH)2 (calcium hydroxidum) is mixed ex tempore with distilled water or sodium chloride isotonic solution. Ready-to-use forms are also produced — pastes with calcium hydroxide Calxil, Calasept (“Nordiska” company), Calciject (“Centrix” company), Hy-Cal (“Pierre Rolland” company). The majority of these medicines are manufactured in plastic syringes with needles or thin plastic cannulae.
It is possible to use gutta-percha posts, containing 58% calcium hydroxide, which beginds to release under the influence of moisture when the post is placed in the canal (usually for three weeks).
A separate group includes calcium hydroxide drugs that contain iodoform: e.g. Vitapex, apexdent.
Medicines based on hydroxylapatite may be used as an alternative to calcium hydroxide and oxide. The following hydroxylapatite-containing medicines are used in endodontics: 30% paste “Ostim-100” or hydroxylapol (polystom) combined with zinc oxide and eugenol.
Antibiotics and corticosteroids are the components of such pastes as Septomixim forte (“Septodont” company), Ledermix (“Lederie” company), Fokalmin (“Lege Artist” company), Dexodent (“Alpha-Beta Medical” company) etc. Paste Grinasole (“Septodont” company) contains 10% metronidazole.
Pastes based on the mixture of prolong-action antiseptics are Tempofore (“Septodont” company): menthol, thymol, creosote, iodoform, camphor, zinc oxide, zinc stearate, barium sulfate; iodent (“VladMiVa” company): iodoform, thymol and camphor.
Pastes for temporary obturation are filled into the canals that were well-treated mechanically and medicamentally. These canals are filled with a rotary paste filler for the period from three days to several weeks. The dental cavity is closed with an occlusive dressing.
After achieving the desired aim, temporary pastes must be removed and the root canals are filled with hardening pastes.
Medical treatment
Sometimes temporary paste obturation is substituted by dressings with liquid medicines on cotton balls, turundas or paper absorption posts. Turundas and posts are placed in root canals with the medicines, whose evaporations have antimicrobic action (camphor- and Р-Сlorophenol, cresatin). Dressings with volatile medicines (clove oil, formocresol, thymol, camphorophenol) in the form of cotton balls may be left only in the canal orifice, while the canal itself must remain empty. Before placing in the dental cavity, the cotton ball is squeezed to avoid the spread of excessive medicine in the periodontium.
Antiseptic dressings may also contain other medicines: dexamethasone, hydrocortisone, guaiacol, phenol, chlorhexidine etc.
At present there are numerous ready-to-use drugs for antiseptic dressings with various components. They include Endotine, Cresophen (“Septodont” company), Mepacyl, Osomol 3, Osomol 4 (“Pierre Rolland” company), Endosept (“Denrare” company), cresodent – liquids (“VladMiVa”, “Raduga-R” and other companies). Using manufactured medicines it is required to thoroughly study the instructions. It is necessary to pay attention to the recommendations as to the medicine use: turunda dressing or canal orifice dressing. Antiseptic dressings are applied for 1-3 days and the dental cavity is closed with an occlusive dressing.