- Email: [email protected]
Bacteriologic study of infected deciduous molars
BACTERIOLOGIC
STUDY
OF INFECTED
DECIDUOUS
MOLARS
T
HERE have been man)- bacteriologic survey-s of devitalized teeth an~ong adults, Studies by and a wide variety of organisms have been dcnionst,ratccl. Sommer and C~rowley,L Morse and I’iit(3,” IIaycs.:’ ant1 Ostrantl~~r and assoThe ciates& demonstrated a variety of organisms in root ca,nals and cultures. bacteria most oftcxn rcporttatl were all)ha h(~molytic~ streptococcus (Streptoc,occm I-Gridnns), rxl6us. pamn~ hcmolytir stt.cIptoc,occ.L~s, and Ytaphylococms Other organisms isoIatcBt1 inclutlocl IlenloIytic strq,tocoecus. Sfccphllloco~~Ics uurezcs, lactobacillus, yWsts, and ~OlltillllillilIltS. X stud?- 1)~ ~~ruchalla and Hamann,” however, showed Str.eljtococc~,ts scrlizvrizls ant1 Sfwpfococcus mitis to be predominant and clelnonstratctl thr SILIIIC,variety of other organisms as were observed in the st,udies dust nrentiollc~~l.‘-’ It is of interest that in all thcsc invchstigations b(+a hcmolytic skept ococci were not isolated frequently, whereas nonhcmolyt.ic and alpha hcmolyti(d streptococci were often obscrvctl. In a ~norc rcccnt study of throat and gingival cultures of 500 young adults by Nassler and MacDonald,” beta hemolytic streptococci were isolatctl from thcb gingiva in 6 per cent of the subjects. The present study jvas untlcrtnkcll to dctc~rminc~ the bactcriolopie flora of open, unfilled, infecttJt1 tl(>citluous tooth. XATERIALS
.\ND
METHODS
Thirty children bctwccn thcl ages of 4 and ti ycaars, who wcr(x rc~l’crrc~l t (1 the Dental Clinic of t,ha Hrookline IIcalt,h Center for routine tlontal L’:IW, XV(JIY~ selected for study. Each child had WIG or mor(’ O~WII, unfilletl. contaminal c,tl deciduous molars. The teeth and gingivae WPI’C c~sanlinctl c*arcfully, and aI1 intraoral rocntgcnogram was taken of one open, ~uifillctl, coritalrlin;ltc~tl tlcGtlllous molar in each child. Each tooth was isolated with a rubb(at+-(lam, and that field of operation (exposed tooth, clamp, and rubbc~r-dam) was stclrilixed with 1 :l,OOO Zephiran chloride solution. of the Health
From the Retch Research Laboratory, Boston Dispensary ; the Bacteriology Laboratorim Pratt Clinic, New Kngland Center Hospital, Boston, Massachusetts: and the Rrookliw Center, Brookline, Massachusetts. This investigation was supportwl by a grant fmnl Ilurrouytrs \Vellcome & C’o.. Inc.
Volume 13 Number 11
INFECTED
DECIDUOUS
MOLARS
1383
from the thirty open teeth were taken with a sterile Cultures .-Cultures cotton point which was inserted into the pulp chamber for approximately one minute. The cotton point was then placed in a sterile vial containing I ml. of The vials were shaken for five minutes in a sterile physiologic saline solution. Kahn shaking machine to disintegrate the cotton point and suspend the orAfter this, a standard loopful of the saline ganisms in the saline solution.7 suspension was plated on a nutrient blood agar plate, a tomato juice agar plate, and a lactobacillus selection agar plate. A loopful was also put into a tube of Brewer’s thioglycollate medium, and the remainder was used to rnakc a poured plate in tomato juice agar for a lactobacillus count. All cultures were incubated at 37O C. for forty-eight hours. The plates were then studied, and the organisms molated on the streaks were noted. The pour plates were counted with the aid of a Quebec colony counter. The tubes of thioglyc’ollate medium were observed for anaerobic growth and wwc sub cultured at the end of forty-eight hours to blood agar, which was then incubated both aerobically and anaerobically in an attempt to isolate fastidious or slow-growing organisms. None of the cultures were considered sterile until the thioglycollate medium had been incubated for five days without showing visible signs of growth. Subcultures.-The mitis and salivarius strains of streptococci were differentiated by subculturing on 5 per cent sucrose agar to demonstrate the characThe streptococci were teristic large mucoid colonies of Streptococws saliearius.” also inoculated into 6.5 per cent sodium chloride broth to determine whether or not they were enterococci6 The hemolytic streptococci were differentiated by their clear zone of hemolysis on blood agar and were t,yped as group A or not group A by means of paper disks impregnated with 0.2 unit of bacitracin.8 No attempt was made to identify the species of lactobacilli, but they were isolated on the selective media (either tomato juice agar or lactobacillus selection agar), and typical colonies were identified by gram-stained smears. Staphylococci were identified on the basis of pigment production by subculture on 10 per cent milk agar plates on which color is clearly defined. All strains were also examined for coagulase activity to ascertain their relative pathogenicity. The enteric bacteria isolated were identified by subculturing on Endo agar plates and by sugar fermentation and other biochemical tests. The miscellaneous saprophytes isolated (neisseria and yeasts) were identified by colonial morphology and biochemical tests. RESULTS
Of the thirty pulp chambers cultured (Table I), twenty-one showed growth of Streptococcus salivarius as determined by subcultures on sucrose agar and failure to grow in 6.5 per cent saline broth. Staphylococcus albus was observed in seven cultures, All produced a white pigment and were coagulase-negative,
COHEN,
1384
JOREXA,
AND
O.S.,0 hl. c;O.P.
CALISTI
Sorembrr.
zz
I
I
CASE NO. 1
I I STREPTOcoccus SALIVARTUS
STREPTOcoccus NITIS
LAC’I’ORACTT,T.I
t+
+
+ ++ ++ +
7 8 9 10 11
STAI’HYLO COCCT~S AUREL-S
ST.4PIIYLO COCCTJS .\T.HI’S
I ENTERIC BACIT,I.I -.---
___-
hlIS(‘~l,IuZNEoI-S __~
+
++
2 3 4 r
BETA HEMOLYTIC STREPTOCOCCI __~
1900
+ f
t
ii
Neiswria
i-t +-I-
+
+I
+
12
+
+
++ ++ ++ ++ +t ++ ++
13 14 15 16 17
+
+
+ 1
t+
20
21 22 23
+i-
24
++
25 26 27 28 29 30
++ ++ ++ ++
t
+ t
-I-
Yeasts ++
____
___-l_---.l--
+t = Heavy growth. + = Moderate qowth.
Gram-negative mtcric bacilli wcrc obsc~r?.odin fi1.c cnitures. 1’11rce of thcsc organisms were differentiated as Escherichict coli 1,~ suhcnlturing on diflcrential media; one was an Acrobactcr species; and one was ;III ~ll(,nli~/c HCSspecies. Beta hemolytic streptococci WE observed in fi1.v cultnrcs. None of theses were identified as group A when typed with bacitracin disks. Lactobaeilli were observed in four cultures, with counts ranging from 1,000 to 5,000. StreptocOccus
mitis
was
obscnwi
in IhiW cnlturc3
Staphylococcus auwus WIS observed in only tn-o cultnrcs. These prodnped a yellow pigment and was coagulase-positive. The saprophytic neisseris found in one ctllt1u.e was determined to bc Ncisseria catarrhalis because of its failnrc to ferment carl)ohydrates. The yeast isolated in one culture was tletcrmined on the basis of its cnltnrcl reactions to be a species of ~crcchnrom~ylc~s. All the deciduous teeth examined in this stud)- manifestc4 roentgenographic evidence of infection, and in seven casts +hcrc wcrcl open. draining fistulas on the labial gingiva of the infected tooth.
INFECTED DECIDUOUS MOLARS
Volume 13
NumberI I
13x5
DISCUSSION
As noted previously, Streptococcus saliva&s was the organism most frequently isolated from open, infected deciduous teeth. Although it is considered to be a normal inhabitant of the mouth, it has been suggested as a potential etiological agent in dental earies.9 The incidence of Streptococcus saliaarius was much higher than noted in most previous studies on adult teeth selected study on infected tcet 11. for root canal therapy.lO In Gruchalla and Hamann’ however, Streptococcus sativarius was found in 45 per cent of 263 CASTS.” Staphylococcus albus was the next most frequently isolated organism. It is known to be a common saprophytic inhabitant of the oral cavity, nonpat,hogertic in nature. The gram-negative enteric bacilli were associated with poor oral hygiene and generalized gingivitis. Lactobaeilli, like Streptococcus salivarius, are considered to be normal inhabitants of the mouth but have been suggested as a potential cause of dental caries.9s I1 Streptococcus mitis, one of the heterogeneous group of green-producing streptococci that are normally found in the oral cavity, has been recovered front blood and heart lesions in bacterial endocarditis.12-14 Prophylactic, antibiotic therapy should be considered when there is a history of rheumatic fever and extraction of infected deciduous teeth is indicated.‘j Although none of the beta hemolytic streptococci isolated in this study were group A organisms, it is possible that group A organisms might be found in a larger study. The beta hemolytic streptococcus is the etiological agent in acute pharyngitis, but only group A organisms have been implieat.ed in glomerulonephritis and rheumatic fever.16T I7 Staphylococcus aureus may be considered a possible source of 1oea.l or systemic infection, especially that associated with pyemia, wound suppuration. osteomyelitis, and furunculosis. The saprophytic organisms isolated in this study are found normally in the oral cavity. SUMMARY
AND
CONCLUSIONS
Organisms isolated in this study were as follows : Organisms Streptococcus salivarius Staphylococcus albus Enterio bacilli Lactobacilli Streptococcus mitis Beta hemolytic streptococci $taphylococcus aureus Neisseria catarrhalis Yeasts
Per (Cent 70 23 17 13 :: t5 :: 3
COHEN,
JORESS,
AND
CALISTI
OS., O.M. & OP. November. 1960
The practice of maintaining open, infected deciduous teeth in the mouths of children is to be condemned because of the variety of the microorganisms found in this study and their potentially harmful effects. Since all casesshowed destruction of bone within the bifurcation of the roots of the deciduous molars and eight cases manifested fistulous tracts on the labial gingiva, such teeth should either be extracted or given appropriate root canal therapy, REFERENCES
Bacteriologic Verification of Boentgenographic R. F., and Crowley, M. C.: Fmdings in Pulp Involved Teeth, J. Am. Dent. A. 27: 723, 1940. Morse? F. W., Jr., and Yates, M. F.: Follow-up Studies of Root Filled Teeth in Relation to Bacteriologic Findings, J. Am. Dent. A. 28: 956, 1941. Hayes, R. L.: Clinical and Bacteriological Study of 349 Pulp Involved Cases, J. D. Res. 22: 301, 1943. Ostrander, F. D., Crowley, M. C., and Dowson, J.: A Clinical Study of the Treatment of Root Canal and Periapical Infections With Penicillin, J. D. Res. 26: 403, 1947. Gruchalla, F. J., and Hamann, C. B.: Root Surgery, J. Missouri Dent. A. 27: 229, 1947. Massler, M., and MacDonald, J. B.: The Occurrence of Beta Hemolytic Streptococci on the Gingiva of Normal Young Adults, J. D. Res. 29: 43, 1950. Schaub, I. G., and Foley, M. K.: Diagnostic Bacteriology, ed. 5, St. Louis, 1955, The C. V. Mosby Company, p. 182. Maxted, W. R.: The Use of Bacitracin for Identifying Group A Hemolytic Streptococci, J. Clin. Path. 6: 224, 1953. A Study of Streptococcus salivarius Shiere, F. R., Georgi, G. E., and Ireland, R. L.: and Its Relationship to the Dental Caries Process, J. Am. Dent. A. 30: 116-125, 1951. Rickert, U. G.: Importance of Extracting Deciduous Teeth and Roots Which Cannot Be Filled, Michigan State D. Sot. Bull. 10: 17, 1928. acidophilus and Dental Caries, J. Am. Dent. A. 16: 230, 1929. Jay, P.: Bacillus Rheumatism and Arthritis (9th Rheum. Rev.), January, 1948. Hench, P. 8.: Streptococcus viridans Bacteremia Following Extraction of the Teeth, Hopkins, J. A.: J. Am. Dent. A. 26: 2002, 1939. Bacteremia and Oral Sepsis With Special Reference O’Kell, C. C., and Eliot, E. D.: to Etiology of Subacute Endocarditis, Lancet 2: 869, 1935. Antibiotics in Oral Surgery, D. Clin. Zubrow, H. J., Spatz, S. S., and Kline, S. N.: North America, pp. 679-690, 1959. Bacterial Infect,ions With Special Reference to Dental PracAppleton, J. L. T., Jr.: tice, ed. 3, Philadelphia, 1944, Lea & Febiger. Newer Aspects of the Problem of Focal Infection, Am. J. Orthodontics & Stein, G.: Oral Surg. 28: 28-42, 1942.
1. Sommey,
2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.
STUDY
OF INFECTED
DECIDUOUS
MOLARS
T
HERE have been man)- bacteriologic survey-s of devitalized teeth an~ong adults, Studies by and a wide variety of organisms have been dcnionst,ratccl. Sommer and C~rowley,L Morse and I’iit(3,” IIaycs.:’ ant1 Ostrantl~~r and assoThe ciates& demonstrated a variety of organisms in root ca,nals and cultures. bacteria most oftcxn rcporttatl were all)ha h(~molytic~ streptococcus (Streptoc,occm I-Gridnns), rxl6us. pamn~ hcmolytir stt.cIptoc,occ.L~s, and Ytaphylococms Other organisms isoIatcBt1 inclutlocl IlenloIytic strq,tocoecus. Sfccphllloco~~Ics uurezcs, lactobacillus, yWsts, and ~OlltillllillilIltS. X stud?- 1)~ ~~ruchalla and Hamann,” however, showed Str.eljtococc~,ts scrlizvrizls ant1 Sfwpfococcus mitis to be predominant and clelnonstratctl thr SILIIIC,variety of other organisms as were observed in the st,udies dust nrentiollc~~l.‘-’ It is of interest that in all thcsc invchstigations b(+a hcmolytic skept ococci were not isolated frequently, whereas nonhcmolyt.ic and alpha hcmolyti(d streptococci were often obscrvctl. In a ~norc rcccnt study of throat and gingival cultures of 500 young adults by Nassler and MacDonald,” beta hemolytic streptococci were isolatctl from thcb gingiva in 6 per cent of the subjects. The present study jvas untlcrtnkcll to dctc~rminc~ the bactcriolopie flora of open, unfilled, infecttJt1 tl(>citluous tooth. XATERIALS
.\ND
METHODS
Thirty children bctwccn thcl ages of 4 and ti ycaars, who wcr(x rc~l’crrc~l t (1 the Dental Clinic of t,ha Hrookline IIcalt,h Center for routine tlontal L’:IW, XV(JIY~ selected for study. Each child had WIG or mor(’ O~WII, unfilletl. contaminal c,tl deciduous molars. The teeth and gingivae WPI’C c~sanlinctl c*arcfully, and aI1 intraoral rocntgcnogram was taken of one open, ~uifillctl, coritalrlin;ltc~tl tlcGtlllous molar in each child. Each tooth was isolated with a rubb(at+-(lam, and that field of operation (exposed tooth, clamp, and rubbc~r-dam) was stclrilixed with 1 :l,OOO Zephiran chloride solution. of the Health
From the Retch Research Laboratory, Boston Dispensary ; the Bacteriology Laboratorim Pratt Clinic, New Kngland Center Hospital, Boston, Massachusetts: and the Rrookliw Center, Brookline, Massachusetts. This investigation was supportwl by a grant fmnl Ilurrouytrs \Vellcome & C’o.. Inc.
Volume 13 Number 11
INFECTED
DECIDUOUS
MOLARS
1383
from the thirty open teeth were taken with a sterile Cultures .-Cultures cotton point which was inserted into the pulp chamber for approximately one minute. The cotton point was then placed in a sterile vial containing I ml. of The vials were shaken for five minutes in a sterile physiologic saline solution. Kahn shaking machine to disintegrate the cotton point and suspend the orAfter this, a standard loopful of the saline ganisms in the saline solution.7 suspension was plated on a nutrient blood agar plate, a tomato juice agar plate, and a lactobacillus selection agar plate. A loopful was also put into a tube of Brewer’s thioglycollate medium, and the remainder was used to rnakc a poured plate in tomato juice agar for a lactobacillus count. All cultures were incubated at 37O C. for forty-eight hours. The plates were then studied, and the organisms molated on the streaks were noted. The pour plates were counted with the aid of a Quebec colony counter. The tubes of thioglyc’ollate medium were observed for anaerobic growth and wwc sub cultured at the end of forty-eight hours to blood agar, which was then incubated both aerobically and anaerobically in an attempt to isolate fastidious or slow-growing organisms. None of the cultures were considered sterile until the thioglycollate medium had been incubated for five days without showing visible signs of growth. Subcultures.-The mitis and salivarius strains of streptococci were differentiated by subculturing on 5 per cent sucrose agar to demonstrate the characThe streptococci were teristic large mucoid colonies of Streptococws saliearius.” also inoculated into 6.5 per cent sodium chloride broth to determine whether or not they were enterococci6 The hemolytic streptococci were differentiated by their clear zone of hemolysis on blood agar and were t,yped as group A or not group A by means of paper disks impregnated with 0.2 unit of bacitracin.8 No attempt was made to identify the species of lactobacilli, but they were isolated on the selective media (either tomato juice agar or lactobacillus selection agar), and typical colonies were identified by gram-stained smears. Staphylococci were identified on the basis of pigment production by subculture on 10 per cent milk agar plates on which color is clearly defined. All strains were also examined for coagulase activity to ascertain their relative pathogenicity. The enteric bacteria isolated were identified by subculturing on Endo agar plates and by sugar fermentation and other biochemical tests. The miscellaneous saprophytes isolated (neisseria and yeasts) were identified by colonial morphology and biochemical tests. RESULTS
Of the thirty pulp chambers cultured (Table I), twenty-one showed growth of Streptococcus salivarius as determined by subcultures on sucrose agar and failure to grow in 6.5 per cent saline broth. Staphylococcus albus was observed in seven cultures, All produced a white pigment and were coagulase-negative,
COHEN,
1384
JOREXA,
AND
O.S.,0 hl. c;O.P.
CALISTI
Sorembrr.
zz
I
I
CASE NO. 1
I I STREPTOcoccus SALIVARTUS
STREPTOcoccus NITIS
LAC’I’ORACTT,T.I
t+
+
+ ++ ++ +
7 8 9 10 11
STAI’HYLO COCCT~S AUREL-S
ST.4PIIYLO COCCTJS .\T.HI’S
I ENTERIC BACIT,I.I -.---
___-
hlIS(‘~l,IuZNEoI-S __~
+
++
2 3 4 r
BETA HEMOLYTIC STREPTOCOCCI __~
1900
+ f
t
ii
Neiswria
i-t +-I-
+
+I
+
12
+
+
++ ++ ++ ++ +t ++ ++
13 14 15 16 17
+
+
+ 1
t+
20
21 22 23
+i-
24
++
25 26 27 28 29 30
++ ++ ++ ++
t
+ t
-I-
Yeasts ++
____
___-l_---.l--
+t = Heavy growth. + = Moderate qowth.
Gram-negative mtcric bacilli wcrc obsc~r?.odin fi1.c cnitures. 1’11rce of thcsc organisms were differentiated as Escherichict coli 1,~ suhcnlturing on diflcrential media; one was an Acrobactcr species; and one was ;III ~ll(,nli~/c HCSspecies. Beta hemolytic streptococci WE observed in fi1.v cultnrcs. None of theses were identified as group A when typed with bacitracin disks. Lactobaeilli were observed in four cultures, with counts ranging from 1,000 to 5,000. StreptocOccus
mitis
was
obscnwi
in IhiW cnlturc3
Staphylococcus auwus WIS observed in only tn-o cultnrcs. These prodnped a yellow pigment and was coagulase-positive. The saprophytic neisseris found in one ctllt1u.e was determined to bc Ncisseria catarrhalis because of its failnrc to ferment carl)ohydrates. The yeast isolated in one culture was tletcrmined on the basis of its cnltnrcl reactions to be a species of ~crcchnrom~ylc~s. All the deciduous teeth examined in this stud)- manifestc4 roentgenographic evidence of infection, and in seven casts +hcrc wcrcl open. draining fistulas on the labial gingiva of the infected tooth.
INFECTED DECIDUOUS MOLARS
Volume 13
NumberI I
13x5
DISCUSSION
As noted previously, Streptococcus saliva&s was the organism most frequently isolated from open, infected deciduous teeth. Although it is considered to be a normal inhabitant of the mouth, it has been suggested as a potential etiological agent in dental earies.9 The incidence of Streptococcus saliaarius was much higher than noted in most previous studies on adult teeth selected study on infected tcet 11. for root canal therapy.lO In Gruchalla and Hamann’ however, Streptococcus sativarius was found in 45 per cent of 263 CASTS.” Staphylococcus albus was the next most frequently isolated organism. It is known to be a common saprophytic inhabitant of the oral cavity, nonpat,hogertic in nature. The gram-negative enteric bacilli were associated with poor oral hygiene and generalized gingivitis. Lactobaeilli, like Streptococcus salivarius, are considered to be normal inhabitants of the mouth but have been suggested as a potential cause of dental caries.9s I1 Streptococcus mitis, one of the heterogeneous group of green-producing streptococci that are normally found in the oral cavity, has been recovered front blood and heart lesions in bacterial endocarditis.12-14 Prophylactic, antibiotic therapy should be considered when there is a history of rheumatic fever and extraction of infected deciduous teeth is indicated.‘j Although none of the beta hemolytic streptococci isolated in this study were group A organisms, it is possible that group A organisms might be found in a larger study. The beta hemolytic streptococcus is the etiological agent in acute pharyngitis, but only group A organisms have been implieat.ed in glomerulonephritis and rheumatic fever.16T I7 Staphylococcus aureus may be considered a possible source of 1oea.l or systemic infection, especially that associated with pyemia, wound suppuration. osteomyelitis, and furunculosis. The saprophytic organisms isolated in this study are found normally in the oral cavity. SUMMARY
AND
CONCLUSIONS
Organisms isolated in this study were as follows : Organisms Streptococcus salivarius Staphylococcus albus Enterio bacilli Lactobacilli Streptococcus mitis Beta hemolytic streptococci $taphylococcus aureus Neisseria catarrhalis Yeasts
Per (Cent 70 23 17 13 :: t5 :: 3
COHEN,
JORESS,
AND
CALISTI
OS., O.M. & OP. November. 1960
The practice of maintaining open, infected deciduous teeth in the mouths of children is to be condemned because of the variety of the microorganisms found in this study and their potentially harmful effects. Since all casesshowed destruction of bone within the bifurcation of the roots of the deciduous molars and eight cases manifested fistulous tracts on the labial gingiva, such teeth should either be extracted or given appropriate root canal therapy, REFERENCES
Bacteriologic Verification of Boentgenographic R. F., and Crowley, M. C.: Fmdings in Pulp Involved Teeth, J. Am. Dent. A. 27: 723, 1940. Morse? F. W., Jr., and Yates, M. F.: Follow-up Studies of Root Filled Teeth in Relation to Bacteriologic Findings, J. Am. Dent. A. 28: 956, 1941. Hayes, R. L.: Clinical and Bacteriological Study of 349 Pulp Involved Cases, J. D. Res. 22: 301, 1943. Ostrander, F. D., Crowley, M. C., and Dowson, J.: A Clinical Study of the Treatment of Root Canal and Periapical Infections With Penicillin, J. D. Res. 26: 403, 1947. Gruchalla, F. J., and Hamann, C. B.: Root Surgery, J. Missouri Dent. A. 27: 229, 1947. Massler, M., and MacDonald, J. B.: The Occurrence of Beta Hemolytic Streptococci on the Gingiva of Normal Young Adults, J. D. Res. 29: 43, 1950. Schaub, I. G., and Foley, M. K.: Diagnostic Bacteriology, ed. 5, St. Louis, 1955, The C. V. Mosby Company, p. 182. Maxted, W. R.: The Use of Bacitracin for Identifying Group A Hemolytic Streptococci, J. Clin. Path. 6: 224, 1953. A Study of Streptococcus salivarius Shiere, F. R., Georgi, G. E., and Ireland, R. L.: and Its Relationship to the Dental Caries Process, J. Am. Dent. A. 30: 116-125, 1951. Rickert, U. G.: Importance of Extracting Deciduous Teeth and Roots Which Cannot Be Filled, Michigan State D. Sot. Bull. 10: 17, 1928. acidophilus and Dental Caries, J. Am. Dent. A. 16: 230, 1929. Jay, P.: Bacillus Rheumatism and Arthritis (9th Rheum. Rev.), January, 1948. Hench, P. 8.: Streptococcus viridans Bacteremia Following Extraction of the Teeth, Hopkins, J. A.: J. Am. Dent. A. 26: 2002, 1939. Bacteremia and Oral Sepsis With Special Reference O’Kell, C. C., and Eliot, E. D.: to Etiology of Subacute Endocarditis, Lancet 2: 869, 1935. Antibiotics in Oral Surgery, D. Clin. Zubrow, H. J., Spatz, S. S., and Kline, S. N.: North America, pp. 679-690, 1959. Bacterial Infect,ions With Special Reference to Dental PracAppleton, J. L. T., Jr.: tice, ed. 3, Philadelphia, 1944, Lea & Febiger. Newer Aspects of the Problem of Focal Infection, Am. J. Orthodontics & Stein, G.: Oral Surg. 28: 28-42, 1942.
1. Sommey,
2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.