JOURNAL OF ENDODONTICS I VOL 2, NO 12, DECEMBER1976
H i s t o l o g i c s t u d y of the e f f e c t s of h y d r o c o r t i s o n e on the apical p e r i o d o n t i u m of d o g s R. G. Smith, DDS, MSD: S a m u e l S Patterson, DDS, MSD; a n d Abdel I-L E1-Kafrawy, BDS, MS]), Indianapolis
T h e root c a n a l s of d o q s ' t e e t h with deliberately opened and unopened apices were treated with hydrocortisone. They were compared histoloqically with opened and unopened untreated apices. The periodontal memb r a n e s a d j a c e n t to u n o p e n e d apices showed a much milder i n f l a m m a t o r y r e s p o n s e t h a n the ones opened, while the unopened steroid-treated canals had the mildest response.
Endodontists often face the problem of controlling pain, particularly the postoperative discomfort attributed to an acute secondary periodontitis, caused by instrumentation and forcing medication a n d / o r necrotic debris, ineluding bacteria, through the apices. 1 Because the periodontal membrane is confined between two rather solid structures--the tooth and the lamina d u r a - - i t cannot swell, and the result is pressure in the area. 2 The pain is usually a dull, steady type. The patient frequently complains that he bites on the affected tooth before his other teeth occlude and that it is then painful. The tooth is tender to percussion.
376
Endodontists often use a combination of a corticosteroid and an antibiotic to reduce inflammation and thus control the pain associated with acute secondary apical periodontitis. The symptomatic results appear to be satisfactory, a-7 Many pulp studies show the use of corticosteroid-antibiotic combinations as pulp-capping medicaments. N o histologic apical periodontal studies have been reported in which these combinations were used as intracanal medication. The purpose of this investigation was twofold: to determine histologically any beneficial or detrimental effects of hydrocortisone on the apical periodontium of dogs' teeth and to determine whether or not it is necessary to force the hydrocortisone through the canal into the apical tissue to be effective.
METHODS AND MATERIALS Six mongrel (part beagle) dogs ranging in age from 9 - t o 14 months were anesthetized by intravenous injection of sodium pentobarbital, using 28 m g / k g of body weight. Endodontic treatment involved the left and right second and third mandibular premolars which were isolated with a rubber dam. These teeth each have two roots, one under each cusp. There is a single canal in each root ending
in multiple, small, almost microscopic ramifications. The cusps were removed, and the flat surfaces were used as planes from which to measure the length of the root canals. By using the radiographic outlines of the pulp chambers and the canals as guides, deep and wide initial coronal openings short of the pulp chamber were made with a no. 701 fissure bur in an air-driven, highspeed handpiece. The actual openings into the pulp chamber then were made with a sterile no. 2 round bur. The depth of the canals was first determined from the radiographic images, using a millimeter ruler. A K file placed in the root canal was marked with a small rubber stopper to show its working length. This was compared with the canal measurement taken from the radiograph. The pulp tissue was removed from the canals. The canals also were enlarged with the K files, irrigated with sterile normal saline solution, and dried with sterile paper points. One of the two canals in the two teeth on one side of the mandibles of the dogs was instrumented with a motor-driven reamer to penetrate the apex. A 2.5% hydrocortisone* acetate ointment then was inserted into both canals with a K file. A reamer .was used to force the hydrocort.isone
JOURNAL OF ENDODONTICS ] VOL 2, NO 12, DECEMBER 1976
through the apex of each canal that had been previously opened with a reamer. The reamer was rotated counterclockwise in each canal with opened apices in an attempt to force the hydrocortisone into the periodontal tissues. The canals of the teeth on the other side of several mandibles were cleansed with K files. Again, only one apex in each tooth was deliberately opened, but no medication was placed in either one of the canals. A pellet of sterile cotton was placed over all of the canal orifices, and the access cavities were filled with zinc oxideeugenol, with zinc acetate added as an accelerator. Postoperative periods of 3, 14, and 45 days passed before the animals were killed with a lethal dose of intravenous sodium pentobarbital. Block sections of the jaws containing the test teeth were fixed in 10% Formalin and decalcified in 5% formic acid. Semiserial 7/~m thick paraffin sections were cut in a mesiodistal direction and stained with hematoxylin and eosin. A few sections from each root apex were stained with Brown and Brenn stain to show bacteria in the apical tissues.
HISTOLOGIC FINDINGS U n o p e n e d A p i c e s With N o Medication 9 Three days. Histologic sections from six apices that were not perforated and in which no hydrocortisone had been placed in the canals were examined. The periodontium around the three apices showed microscopically a mild reaction with scattered leukocytes in the periapical area. Three apices showed a moderate reaction with a more dense infiltration of leukocytes; bone resportion was evident in five specimens (Fig 1). 9 Fourteen days. Five specimens were examined in this group. Again, the
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H i s t o l o g i c s t u d y of the e f f e c t s of h y d r o c o r t i s o n e on the apical p e r i o d o n t i u m of d o g s R. G. Smith, DDS, MSD: S a m u e l S Patterson, DDS, MSD; a n d Abdel I-L E1-Kafrawy, BDS, MS]), Indianapolis
T h e root c a n a l s of d o q s ' t e e t h with deliberately opened and unopened apices were treated with hydrocortisone. They were compared histoloqically with opened and unopened untreated apices. The periodontal memb r a n e s a d j a c e n t to u n o p e n e d apices showed a much milder i n f l a m m a t o r y r e s p o n s e t h a n the ones opened, while the unopened steroid-treated canals had the mildest response.
Endodontists often face the problem of controlling pain, particularly the postoperative discomfort attributed to an acute secondary periodontitis, caused by instrumentation and forcing medication a n d / o r necrotic debris, ineluding bacteria, through the apices. 1 Because the periodontal membrane is confined between two rather solid structures--the tooth and the lamina d u r a - - i t cannot swell, and the result is pressure in the area. 2 The pain is usually a dull, steady type. The patient frequently complains that he bites on the affected tooth before his other teeth occlude and that it is then painful. The tooth is tender to percussion.
376
Endodontists often use a combination of a corticosteroid and an antibiotic to reduce inflammation and thus control the pain associated with acute secondary apical periodontitis. The symptomatic results appear to be satisfactory, a-7 Many pulp studies show the use of corticosteroid-antibiotic combinations as pulp-capping medicaments. N o histologic apical periodontal studies have been reported in which these combinations were used as intracanal medication. The purpose of this investigation was twofold: to determine histologically any beneficial or detrimental effects of hydrocortisone on the apical periodontium of dogs' teeth and to determine whether or not it is necessary to force the hydrocortisone through the canal into the apical tissue to be effective.
METHODS AND MATERIALS Six mongrel (part beagle) dogs ranging in age from 9 - t o 14 months were anesthetized by intravenous injection of sodium pentobarbital, using 28 m g / k g of body weight. Endodontic treatment involved the left and right second and third mandibular premolars which were isolated with a rubber dam. These teeth each have two roots, one under each cusp. There is a single canal in each root ending
in multiple, small, almost microscopic ramifications. The cusps were removed, and the flat surfaces were used as planes from which to measure the length of the root canals. By using the radiographic outlines of the pulp chambers and the canals as guides, deep and wide initial coronal openings short of the pulp chamber were made with a no. 701 fissure bur in an air-driven, highspeed handpiece. The actual openings into the pulp chamber then were made with a sterile no. 2 round bur. The depth of the canals was first determined from the radiographic images, using a millimeter ruler. A K file placed in the root canal was marked with a small rubber stopper to show its working length. This was compared with the canal measurement taken from the radiograph. The pulp tissue was removed from the canals. The canals also were enlarged with the K files, irrigated with sterile normal saline solution, and dried with sterile paper points. One of the two canals in the two teeth on one side of the mandibles of the dogs was instrumented with a motor-driven reamer to penetrate the apex. A 2.5% hydrocortisone* acetate ointment then was inserted into both canals with a K file. A reamer .was used to force the hydrocort.isone
JOURNAL OF ENDODONTICS ] VOL 2, NO 12, DECEMBER 1976
through the apex of each canal that had been previously opened with a reamer. The reamer was rotated counterclockwise in each canal with opened apices in an attempt to force the hydrocortisone into the periodontal tissues. The canals of the teeth on the other side of several mandibles were cleansed with K files. Again, only one apex in each tooth was deliberately opened, but no medication was placed in either one of the canals. A pellet of sterile cotton was placed over all of the canal orifices, and the access cavities were filled with zinc oxideeugenol, with zinc acetate added as an accelerator. Postoperative periods of 3, 14, and 45 days passed before the animals were killed with a lethal dose of intravenous sodium pentobarbital. Block sections of the jaws containing the test teeth were fixed in 10% Formalin and decalcified in 5% formic acid. Semiserial 7/~m thick paraffin sections were cut in a mesiodistal direction and stained with hematoxylin and eosin. A few sections from each root apex were stained with Brown and Brenn stain to show bacteria in the apical tissues.
HISTOLOGIC FINDINGS U n o p e n e d A p i c e s With N o Medication 9 Three days. Histologic sections from six apices that were not perforated and in which no hydrocortisone had been placed in the canals were examined. The periodontium around the three apices showed microscopically a mild reaction with scattered leukocytes in the periapical area. Three apices showed a moderate reaction with a more dense infiltration of leukocytes; bone resportion was evident in five specimens (Fig 1). 9 Fourteen days. Five specimens were examined in this group. Again, the
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