NFECTION
IS M O U TH IN G BEFORE DENTAL CONTROL Without adequate protec tion, dental practitioners risk infection from micro organisms from patients’ mouths. The authors discuss the role of pre procedural mouthrinses in the infection control process.
PROCEDURES WORTHWHILE?
JOHN A. MOLINARI, PH.D.; GAIL- E. MOLINARI, D.D.S., M.S.
f y en tal care providers are routinely exposed to a m ulti tude of bacterial, viral, fungal and other microbial pathogens during p a tie n t treatm ent. As obvious as this statem ent sounds today, it w asn’t until sensitive serological assays and improved microbial culture techniques were developed th a t the risks of cross-infection from diseases such as hepatitis B, herpesviruses, tuberculosis, staphylococci and others were elucidated. As a consequence, m any health professionals responded by incorporating better microbial disease prevention m easures into their professional activities. D ental professionals have addressed th e increased challenge of infectious disease and infection control by em pha sizing seven m ajor areas: asep tic technique, patien t screening and evaluation, personal protec tion, in stru m en t sterilization, environm ental surface disin fection, equipm ent asepsis and laboratory asepsis. Each infection control component contributes to m inim izing the potential for cross-infection during provision of dental treatm ent. Modes of microbial tra n s m ission in the dental environ m ent m ay be classified into
th ree general categories: " direct contact w ith infectious lesions, blood or saliva; " indirect transm ission via tran sfer of m icroorganism s by a contam inated interm ediate object; " aerosolization via the airborne tran sfer of infected blood, saliva or nasopharyngeal secretion droplets, or all three. W hile m uch has been learned since the A m erican D ental Association published its initial infection control recom m en dations in 1978,1it is im portant to realize th a t basic principles of disease transm ission and prevention were considered m any years earlier.2 L ister’s un tirin g efforts led to the introduction of the first chemo therapeutic chemical agent, carbolic acid, into medical and dental practice. This all purpose phenolic was effective in reducing postoperative infections in hospitalized patients through its suggested uses as a ste rila n t for in stru m ents, as a disinfectant for wounds and surgical sites on patients and as a handw ash antiseptic for clinical personnel. Since th eir w idespread in tro duction in the mid-1800s, later generations of antim icrobial chem otherapeutic substances have touched every health care JADA, Vol. 123, March 1992
75
INFECTION
CONTROL
Tattle 1
REPRESENTATIVE HUMAN ORAE EEORA Gram-positive facultative cocoi
Gram-negative facultative rods
S ta p h y lo c o c c u s e p id e r m id is
Erzter oba cteriaceae
S ta p h . a u re u s
H e m o p h ilu s in flu en za e
S tre p to c o c c u s m u ta n s
E ik e n e lla co rro d en s
S tr e p . s a n g u is
A c tin o b a c illu s
S tre p , m itis
a c tin o m y c e te m c o m ita n s
S tre p , scilioa riu s
C a m p y lo b a c te r s p u to r u m
S tre p , fa e c a lis
C a p n o cyto p h a g a och racea
B e ta -h e m o ly tic streptococci
Cap. s p u tig e n a
(o th er th a n group A) Gram-negative anaerobic rods Gram-positive anaerobic cocci
W olin ella recta
JPeptostreptococcus sp.
B a c te ro id e s a sa c c h a r o ly tic u s
Gram-positive anaerobic cocci
B. f r a g ilis
D ip h th e ro id s
B. loescheii
B. g in g iv a lis
C o ry n e b a c te riu m m a tru c h o tii
B. m e la n in o g en icu s
R o th ia d e n to c a rio sa
B. o r a lis
Gram-positive anaerobic
E u so b a cteriu m p e r id o n tic u m
or microaerophilic rods
E. n u clea tu m
A c tin o m y c e s is r a e lii
S ele n o m o n a s s p u tig e n a
E e p to tric h ia b u cca lis
A. n a e s lu n d ii A. o d o n to ly tic u s
Spirochetes
A. u iscosus
T rep on em a d e n tic o la
F*ropionibctcteri um acn es
T. m ic ro d e n tiu m
AToraocella c a ta r r h a lis
T. o r a le
L a c to b a c illu s sp.
T. u incentii
Gram-negative aerobic or facultative
Yeasts
cocci
C a n d id a a lb ic a n s
E u b a c te r iu m le n tu m
G eo trich u m sp.
N e is s e r ia sicca IV. flau escen s
Protozoa
E n ta m o e b a g in g iu a lis Gram-negative anaerobic cocci
T rich o m o n a s ten ax
Veil lon e Ila a lca lescen s V. p a r u u la
Mycoplasma
M y c o p la sm a o ra le Ad. p n eu m o n ia e ( A d a p te d fro m C h a n d r a s e k a r P H , M o lin a ri JA . E n d o g e n o u s a n a e r o b e s in o ro fa c ia l in fe c tio n s . I n fe c t S u r g 1 9 3 6 ;5 :2 1 7-2 4.)
discipline. They serve in varied capacities, including antibiotics to assist in recovery from infection, chemical sterilants 76
JADA, Vol. 123, March 1992
and disinfectants to help m inimize cross-contamination, and tissue antiseptics to control the microbial flora on body
surfaces. One application th a t has recently stim ulated extensive discussion is the use of an antiseptic m outhrinse
INFECTION
T ab le 2
CONTROL
transm issions, the p a tie n t’s m outh rem ains as a source of potential cross infection betw een E x a m p le p a tie n t and provider. The following ques C h lorh ex id in e, a le x id in e tions should therefore O cten id in e be considered as we Iodine, iodophors, flu orides look for practical M ercury, tin , zinc strategies to achieve S a n g u in a r in e b e tte r asepsis in our P ero x id e, perborate tre a tm e n t settings: P h en o l, th ym o l, h exylresorcin ol ■■ W hat properties H e x e tid in e should an infection B e n z e th o n iu m chloride, control m outhrinse cety lp y r id in iu m chloride possess? ■■ W hich chemical classes have been investigated as antiseptic offering m ultiple m icroenviron m outhrinses? m ents, appropriate tem perature ™ W hat d a ta have been and an abundance of suitable generated to support the use of nutrients. In addition to the such a m easure? broad range of representative ™ W hat fu rth e r studies need to aerobic, facultative and be perform ed to justify p atien t anaerobic bacteria listed in and tre a tm e n t provider Table l , 3 m ost adults have been benefits? infected w ith and shed herpes ■■ Are th e cost-benefit viruses (th a t is, herpes simplex comparisons reasonable? virus, cytomegalovirus, EpsteinB arr virus), and certain respir P R O P E R T IE S O F AIM atory viruses such as entero IN F E C T IO N C O N T R O L M O U T H R IN S E viruses and rhinoviruses. M any types of microbial Antimicrobial chemicals are pathogens th a t have been widely used in h e a lth care isolated from oral and naso facilities ranging from a n ti pharyngeal secretions,4 coupled biotics to antiseptics to w ith norm al autogenous micro sterilants and disinfectants. organism s, poses a substantial When chemical agents are infection risk. W ithout considered for use, th eir clinical adequate protective m easures, applications and lim itations practitioners and th eir auxil should first be com pared w ith iary staff face a constant risk of the desirable properties for an infection from oral or systemic ideal agent. An ideal pre m icroorganisms tran sm itted procedural antiseptic m outh from the m ouths of th eir rinse should: patients. "■ have an antim icrobial While the use of personal spectrum appropriate for the protective m easures such as site of application; approved vaccines, gloves, “ exhibit selective activity for m asks, eyewear and rubber some essential microbial dam s have lowered the risk of biochemical reaction th a t is not m any potential infectious
REPRESENTATIVE CLASSES OF ORAL ANTISEPTIC AGENTS C la s s
33is-biguanides B is-p y rid in e s H a lo g en s H e a v y m e ta l s a lts H erb al ex tra ct O x y g e n a tin g a g e n ts P h en o lic com p ou n ds P y rim in id es Q u atern a ry a m m on iu m com p ou n ds
preparation as a routine infection control component. W ith th e seven m ajor infec tion control areas m entioned here as a fram ew ork, this procedure would seem to fit best under the heading of aseptic technique. Spirited debate continues, however, as to the efficacy of pre-procedural antim icrobial m outhrinses in this capacity. A lthough a large volume of lite ra tu re has dem onstrated the effectiveness of certain antiseptic m outh rinses in helping to reduce developm ent of gingivitis and periodontitis, th is paper concentrates on th e infection control applications of a pre procedural m outhrinse. These include possible use as a protective m easure for prevent ing endogenous infection in patients and as a useful technique to m inim ize potential cross-infection betw een patients and tre a tm e n t providers. O R A L M IC R O F L O R A AMD O C C U P A T IO N A L R IS K S
The hum an m outh is an ideal incubator for a wide range of potential microbial pathogens,
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CONTROL
an essential reaction of host cells; ■■ be rapidly effective against m icroorganism s; ™ be able to directly kill or inactivate susceptible organism s (th a t is, bactericidal instead of bacteriostatic); “ not induce microbial resistance; ™ be stable and not inactivated by body cells, fluids or infection exudates; “ ■ have a low-surface tension to facilitate penetration, but should not be absorbed by tissues sufficiently to cause local or system ic toxicity; ■■ have a good therapeutic index (th a t is, effective against m icroorganism s a t a concentra tion th a t will not irrita te tissues or interfere w ith tissue healing); " not induce hypersensitivity w ith repeated application; ™ have a residual effect after each use; and ■■ be of reasonable cost for routine use. A lthough a variety of chemical classes have been tested and used as antiseptic m outhrinses, no currently available preparation m eets all of th e foregoing criteria. C H E M IC A L C L A S S E S IN V E S T IG A T E D A S A N T IS E P T IC M O U T H R IN S E S
The search for clinically useful antiseptic agents to assist in controlling th e oral microbial flora is ongoing. Most investi gations have focused on chemo th erapeutic substances th a t affect plaque form ation and gingivitis or periodontitis. Table 2 lists the m ajor classes of antiseptic agents and represen tative compounds for each. (An excellent review5 giving details of properties, m echanism s of 78
JADA, Vol. 123, March 1992
action and efficacy studies appeared in 1988.) R E P R E S E N T A T IV E D A T A S U P P O R T IN G P R E -P R O C E D U R A L A N T IS E P T IC S
Use of pre-procedural a n ti septics is not a recent event, and in fact was advocated years ago. Early studies often involved topical application before injection of local anes thetics, to prevent injection site infections.6 In this study, six preparations were tested. Both 2 percent tincture and aqueous iodines and 2 percent H ibitane (a 2 percent chlorhexidine in alcohol) were found to provide the best antim icrobial activity on oral mucosa. More recently a 0.12 percent chlorhexidine gluconate (CHG) perioperative rinse was shown to clinically reduce the inci dence of alveolar osteitis by 60 percent, w hen compared to placebo controls after surgical removal of im pacted m andib u lar th ird m olars.7 Implications for use of pre-procedural m outh rinses have also been discussed in other studies8 and published guidelines concerning the prevention of infective endocar ditis.910 R esults of a seven-year investigation of p atients with rheum atic h e a rt disease or prosthetic h e a rt valves sug gested th a t rinsing w ith CHG before each dental treatm en t session lessened the chances of bacterem ia by lowering the m icrobial flora concentration.8 The Am erican H eart Assoc iation’s recom m endations for prevention of bacterial endo carditis also address this issue by statin g “... chlorhexidine may be used as an adjunct to a n ti biotic prophylaxis, particularly in patients who are a t high risk and/or have poor dental
ADA MATERIALS
AVAILABLE Q he ADA, through its D epartm ent of Salable M aterials, offers a variety of m aterials designed to help d entists and patients become b e tte r informed on infecton control procedures. These m aterials include: ™ A new eight-m inute p atien t education videotape to assist dentists in com m unicating about infection control procedures used in dental offices. Available M ay 1992. Code: P839; m em b er price: $35. ■■ “Infection Control in the D ental E nvironm ent,” a video and training m anual for th e entire office staff. Code: S548; m em ber price: $75. ™ “Safety and Infection Control M onograph,” inform ation on products for sterilization and disinfection, plus safety and handling precautions for m aterials and equipm ent. Code: S038; m em b er price: $9.95. ™ “F acts About HIV and Infection Control,” a six-page p atien t education pam phlet th a t addresses patient concerns about dental-office infection control procedures. Code: W133; m em ber price: 25/$5.25, 100/$19.95. To order any or all of these item s, contact the D epartm ent of Salable M aterials on its toll-free line: 1(800)947-4746. .
INFECTION
hygiene.”9 We caution however, not to incorrectly in te rp re t this statem en t as a requirem ent for antiseptic m outhrinse use as a component of endocarditis prevention. A nother area of investigation th a t allows for the consider ation of pre-procedural m outh rinses concerns the potential of dental aerosols and spatter droplets to tra n sm it micro organism s. Some dental procedures produce aerosols and sp a tte r th a t can contain microbial concentrations high enough to be considered occupationally hazardous.1112 C haracterization of aerosolized particles and potentially infectious sequelae represents ongoing areas of m edical13 and d e n ta l11,1214 research. Although no commercially available preparation possesses all of th e ideal properties listed previously, 0.12 percent CHG appears to currently demon stra te necessary efficacious characteristics. Its broad antim icrobial effects include significant reductions in the num bers of total aerobes (65 percent to 85 percent reduc tion), anaerobes (42 percent to 80 percent), streptococci (44 percent to 78 percent), and actinomyces (85 percent to 97 percent).15 This study also found th a t repeated rinsing with CHG did not produce a dem onstrable shift in the oral microbial flora. The bis-biguanide th u s did not stim ulate a favorable environ m ent for growth of possible opportunistic microbial species. A subsequent clinical report docum ented an im m ediate and prolonged antim icrobial effect on salivary bacteria after a single 0.12 percent CHG rinse.16 The total anaerobic bacterial population in saliva was
reduced significantly w ithin one m inute after a single rinse with CHG. Additional supporting inform ation for CHG use in controlling potential microbial pathogens was provided when continued analysis of the microbial flora dem onstrated a five-hour antim icrobial effect. The reduction in salivary m icrobial concentration also persisted throughout a 30m inute dental prophylaxis. These clinical d ata were later su b stantiated and expanded to include the effects of two consecutive pre-procedural rinses. Repeated use of 0.12 percent CHG in this m anner had a significant (up to 97 percent reduction) and sus tained effect on the salivary bacterial load.17 Significant reductions in aerobic and facultative bacteria were noted despite th e presence of bioburden such as blood and debris associated w ith scaling and root planing procedures. Virucidal activity has also been dem onstrated in vitro against herpes simplex virus, cytomegalovirus, influenza A, parainfluenza, and hepatitis B viruses in as brief an exposure as 30 seconds.18Poliovirus was not inactivated in vitro, possibly because of the absence of a lipid envelope on the viral surface. Lim ited in vivo data are avail able; however, yet in a t least one study CHG reduced the developm ent of viral lesions and viral titers when applied topic ally onto the skin of herpes simplex virus type 1-infected mice.19 FUTURE C O N S ID E R A T IO N S
Concern about asepsis in the health professions has increased in recent years, in
CONTROL.
p a rt because o documented hazards of disease transm ission and public Dr. John Molinari is anxiety about professor and the perception chairman, Depart ment of Biomedical of risk. D ental Sciences, University care providers of Detroit Mercy School of Dentistry, have 2985 E. Jefferson responded Ave., Detroit 48207. professionally Address reprint requests to Dr. John to the m any Molinari. clinical challenges by im plem enting routine infection control m easures th a t benefit both patients and practitioners. In h eren t in these techniques and protocols is the realization th a t application of infection control principles is dynamic and not static. As new infec tious disease data and s tra te gies for control become avail able, health care workers will have other choices to consider. The use of pre-procedural m outhrinses as a component of a practice’s infection control regim en should be considered in light of scientific progress and unansw ered questions. W ith the exception of fluorides, no group of oral antiseptic agents has received as m uch experi m ental atten tio n as the bisbiguanides. The effectiveness of CHG h as been extensively studied over the past 20 years. W hen the science is viewed in the context of infection control criteria, we notice far more docum ented inform ation to sub stan tiate prevention of endogenous patien t infection th an cross-infection to tre a tm e n t providers. M ultiple applications of CHG have helped to control the onset of opportunistic infections in m any groups of im m une JADA, Vol. 123, March 1992
79
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CONTROL
compromised individuals, including bone m arrow tra n sp la n t patients, Dr. Gail Molinari is cancer assistant professor and chairman, patients, and Department of HIV-infected Pediatric Dentistry, individuals. University of Detroit Mercy School of Definitive Dentistry. proof demon stra tin g protec tion for dental professionals is m uch more difficult to obtain. Study design m u st face the reality th a t percutaneous sharps injuries to h ealth care w orkers occur interm ittently and are not alw ays noted. Also, the im m une defenses can differ betw een different individuals, thereby causing variation in docum enting specific occupational infections. Such projects would require years of following thousands of subjects, to gath er significant d a ta related to protection from infection. In the m eantim e, the im plications from available d a ta will have to suffice. D ental professionals can weigh the cost of pre-procedural m outhrinsing against potential protective benefits of reducing the spread of m icroorganism s from the p a tie n t’s mouth. But the dental profession has already assum ed major infection control costs. Unless an accommodation is reached w ith other groups, such as th ird-party carriers, the cost of this procedure m ay have to be passed onto patients. P atien t com plaints of bitter ta ste and sta in m ay be placated a fter the infection control rationale for the procedure is
80
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explained to them . While the choice is not a simple one, be rem inded th a t dental personnel have faced greater infection control challenges such as the w earing of gloves and receipt of hepatitis B vaccines. ■ 1. A D A C o u n cils on D e n ta l M a te ria ls a n d D evices; D e n ta l T h e ra p e u tic s . In fe c tio n c o n tro l in t h e d e n ta l office. JA D A 1978;97:673-7. 2. L is te r J . O n th e a n tis e p tic p rin c ip le o f th e p ra c tic e o f su rg e ry . B r M ed J (1867; S e p t 21). 3. C h a n d r a s e k a r P H , M o lin a ri J A . E n d o g e n o u s a n a e ro b e s in o rofacial in fe c tio n s. In fe c t S u rg 1986;5:217-24. 4. ADA R e s e a rc h In s titu te , D e p a r tm e n t o f Toxicology. In fe c tio u s h a z a r d s for b o th d e n ta l p e rs o n n e l a n d p a tie n ts in th e o p e ra to ry . JA D A 198 8 ;1 17:374. 5. M a n d el ID. C h e m o th e ra p e u tic a g e n ts for c o n tro llin g p la q u e a n d g in g iv itis. J C lin P erio d o n to l 1988;15:488-98. 6. C aw so n RA, C u rso n I. T h e e ffe c tiv e n e ss o f som e a n tis e p tic s on th e o ral m u co u s m e m b ra n e . B r D e n t J 1959;208-11. 7. L a rse n P E . T h e effect o f a c h lo rh e x id in e r in s e on th e in cid en ce o f a lv e o la r o s te itis fo llo w in g th e su rg ic a l rem o v a l o f im p a c te d m a n d ib u la r th ir d m o la rs. J O ra l M ax illo fac S u r g 1991;49:932-7. 8. T z u k e rt AA, L e v in er E , S e la M. P re v e n tio n o f in fe c tiv e en d o c ard itis: n o t b y a n tib io tic s alo n e. O ra l S u rg O ra l M ed O ra l P a th o l 1986;62:385-8. 9. D a ja n i AS, e t a l. P re v e n tio n o f b a c te ria l e n d o c a rd itis —rec o m m e n d a tio n s b y t h e A m e ric a n H e a r t A sso ciatio n . JA M A 1990;264:2919-22. 10. B arco CT. P re v e n tio n o f in fe c tiv e e n d o c ard itis: a rev ie w o f t h e m ed ic a l a n d d e n ta l lite r a tu r e . J P e rio d o n to l 1991;62:510-23. 11. M icik R E , M ille r RL, M a z a r r e lla M A, Ryge G. S tu d ie s on d e n ta l aerobiology: 1. B a c te ria l aero so ls g e n e ra te d d u rin g d e n ta l p ro ce d u re s. J D e n t R es 1969;48:49-56. 12. M ille r RL, M icik R E , A b el C, Ryge G. S tu d ie s on d e n ta l aerobiology: II. M ic ro b ia l s p la tte r d isc h a rg e d from th e o ra l c a v ity o f d e n ta l p a tie n ts . J D e n t R es 1971;50:621-5. 13. W e n tzell JM , R o b in so n J K , W e n tz e ll J M J r, S c h w a rtz D E , C a rlso n S E . P h y s ic a l p ro p e rtie s of ae ro so ls p ro d u ce d by d e rm a b ra s io n . A rch D e rm a to l 1989;125:1637-43. 14. R osen S, S c h m a k e l D, S c h o e n e r M. In cid e n c e o f r e s p ira to ry d ise a s e in d e n ta l h y g ie n is ts a n d d ie titia n s . C lin P re v D e n t 1985;7:24-5. 15. B rin e r W W , e t al. E ffe c t o f c h lo rh e x id in e g lu c o n a te m o u th rin s e on p la q u e b a c te ria . J P e rio R es (Suppl)1986;21:44-52. 16. W eeks C, B rin e r W , R e b its k i G , V ick V , F e lle r M . Im m e d ia te a n d p ro lo n g ed effect o f 0.1 2 p e rc e n t ch lo rh e x id in e o n s a liv a ry b a c te ria . J D e n t R es 1988;67:326. 17. V e k s le r A E , K a y ro u z GA, N e w m a n MG. R ed u ctio n o f s a liv a ry b a c te r ia b y p re p ro c e d u ra l rin s e s w ith c h lo rh e x id in e 0.12% . J P e rio d o n to l 1991;62:649-51. 18. B e rn s te in D , e t al. In v itro v iru c id a l e ffectiv en ess o f a 0.1 2 p e rc e n t c h lo rh e x id in e g lu co n a te m o u th rin s e . J D e n t R e s 1990;69:874-6. 19. P a r k J B , P a r k N H . E ffe c t o f c h lo rh e x id in e on th e in v itro a n d in vivo h e rp e s sim p le x v iru s in fectio n . O ra l S u rg O ra l M ed O ra l P a th o l 1989;67:149-53.
IS M O U TH IN G BEFORE DENTAL CONTROL Without adequate protec tion, dental practitioners risk infection from micro organisms from patients’ mouths. The authors discuss the role of pre procedural mouthrinses in the infection control process.
PROCEDURES WORTHWHILE?
JOHN A. MOLINARI, PH.D.; GAIL- E. MOLINARI, D.D.S., M.S.
f y en tal care providers are routinely exposed to a m ulti tude of bacterial, viral, fungal and other microbial pathogens during p a tie n t treatm ent. As obvious as this statem ent sounds today, it w asn’t until sensitive serological assays and improved microbial culture techniques were developed th a t the risks of cross-infection from diseases such as hepatitis B, herpesviruses, tuberculosis, staphylococci and others were elucidated. As a consequence, m any health professionals responded by incorporating better microbial disease prevention m easures into their professional activities. D ental professionals have addressed th e increased challenge of infectious disease and infection control by em pha sizing seven m ajor areas: asep tic technique, patien t screening and evaluation, personal protec tion, in stru m en t sterilization, environm ental surface disin fection, equipm ent asepsis and laboratory asepsis. Each infection control component contributes to m inim izing the potential for cross-infection during provision of dental treatm ent. Modes of microbial tra n s m ission in the dental environ m ent m ay be classified into
th ree general categories: " direct contact w ith infectious lesions, blood or saliva; " indirect transm ission via tran sfer of m icroorganism s by a contam inated interm ediate object; " aerosolization via the airborne tran sfer of infected blood, saliva or nasopharyngeal secretion droplets, or all three. W hile m uch has been learned since the A m erican D ental Association published its initial infection control recom m en dations in 1978,1it is im portant to realize th a t basic principles of disease transm ission and prevention were considered m any years earlier.2 L ister’s un tirin g efforts led to the introduction of the first chemo therapeutic chemical agent, carbolic acid, into medical and dental practice. This all purpose phenolic was effective in reducing postoperative infections in hospitalized patients through its suggested uses as a ste rila n t for in stru m ents, as a disinfectant for wounds and surgical sites on patients and as a handw ash antiseptic for clinical personnel. Since th eir w idespread in tro duction in the mid-1800s, later generations of antim icrobial chem otherapeutic substances have touched every health care JADA, Vol. 123, March 1992
75
INFECTION
CONTROL
Tattle 1
REPRESENTATIVE HUMAN ORAE EEORA Gram-positive facultative cocoi
Gram-negative facultative rods
S ta p h y lo c o c c u s e p id e r m id is
Erzter oba cteriaceae
S ta p h . a u re u s
H e m o p h ilu s in flu en za e
S tre p to c o c c u s m u ta n s
E ik e n e lla co rro d en s
S tr e p . s a n g u is
A c tin o b a c illu s
S tre p , m itis
a c tin o m y c e te m c o m ita n s
S tre p , scilioa riu s
C a m p y lo b a c te r s p u to r u m
S tre p , fa e c a lis
C a p n o cyto p h a g a och racea
B e ta -h e m o ly tic streptococci
Cap. s p u tig e n a
(o th er th a n group A) Gram-negative anaerobic rods Gram-positive anaerobic cocci
W olin ella recta
JPeptostreptococcus sp.
B a c te ro id e s a sa c c h a r o ly tic u s
Gram-positive anaerobic cocci
B. f r a g ilis
D ip h th e ro id s
B. loescheii
B. g in g iv a lis
C o ry n e b a c te riu m m a tru c h o tii
B. m e la n in o g en icu s
R o th ia d e n to c a rio sa
B. o r a lis
Gram-positive anaerobic
E u so b a cteriu m p e r id o n tic u m
or microaerophilic rods
E. n u clea tu m
A c tin o m y c e s is r a e lii
S ele n o m o n a s s p u tig e n a
E e p to tric h ia b u cca lis
A. n a e s lu n d ii A. o d o n to ly tic u s
Spirochetes
A. u iscosus
T rep on em a d e n tic o la
F*ropionibctcteri um acn es
T. m ic ro d e n tiu m
AToraocella c a ta r r h a lis
T. o r a le
L a c to b a c illu s sp.
T. u incentii
Gram-negative aerobic or facultative
Yeasts
cocci
C a n d id a a lb ic a n s
E u b a c te r iu m le n tu m
G eo trich u m sp.
N e is s e r ia sicca IV. flau escen s
Protozoa
E n ta m o e b a g in g iu a lis Gram-negative anaerobic cocci
T rich o m o n a s ten ax
Veil lon e Ila a lca lescen s V. p a r u u la
Mycoplasma
M y c o p la sm a o ra le Ad. p n eu m o n ia e ( A d a p te d fro m C h a n d r a s e k a r P H , M o lin a ri JA . E n d o g e n o u s a n a e r o b e s in o ro fa c ia l in fe c tio n s . I n fe c t S u r g 1 9 3 6 ;5 :2 1 7-2 4.)
discipline. They serve in varied capacities, including antibiotics to assist in recovery from infection, chemical sterilants 76
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and disinfectants to help m inimize cross-contamination, and tissue antiseptics to control the microbial flora on body
surfaces. One application th a t has recently stim ulated extensive discussion is the use of an antiseptic m outhrinse
INFECTION
T ab le 2
CONTROL
transm issions, the p a tie n t’s m outh rem ains as a source of potential cross infection betw een E x a m p le p a tie n t and provider. The following ques C h lorh ex id in e, a le x id in e tions should therefore O cten id in e be considered as we Iodine, iodophors, flu orides look for practical M ercury, tin , zinc strategies to achieve S a n g u in a r in e b e tte r asepsis in our P ero x id e, perborate tre a tm e n t settings: P h en o l, th ym o l, h exylresorcin ol ■■ W hat properties H e x e tid in e should an infection B e n z e th o n iu m chloride, control m outhrinse cety lp y r id in iu m chloride possess? ■■ W hich chemical classes have been investigated as antiseptic offering m ultiple m icroenviron m outhrinses? m ents, appropriate tem perature ™ W hat d a ta have been and an abundance of suitable generated to support the use of nutrients. In addition to the such a m easure? broad range of representative ™ W hat fu rth e r studies need to aerobic, facultative and be perform ed to justify p atien t anaerobic bacteria listed in and tre a tm e n t provider Table l , 3 m ost adults have been benefits? infected w ith and shed herpes ■■ Are th e cost-benefit viruses (th a t is, herpes simplex comparisons reasonable? virus, cytomegalovirus, EpsteinB arr virus), and certain respir P R O P E R T IE S O F AIM atory viruses such as entero IN F E C T IO N C O N T R O L M O U T H R IN S E viruses and rhinoviruses. M any types of microbial Antimicrobial chemicals are pathogens th a t have been widely used in h e a lth care isolated from oral and naso facilities ranging from a n ti pharyngeal secretions,4 coupled biotics to antiseptics to w ith norm al autogenous micro sterilants and disinfectants. organism s, poses a substantial When chemical agents are infection risk. W ithout considered for use, th eir clinical adequate protective m easures, applications and lim itations practitioners and th eir auxil should first be com pared w ith iary staff face a constant risk of the desirable properties for an infection from oral or systemic ideal agent. An ideal pre m icroorganisms tran sm itted procedural antiseptic m outh from the m ouths of th eir rinse should: patients. "■ have an antim icrobial While the use of personal spectrum appropriate for the protective m easures such as site of application; approved vaccines, gloves, “ exhibit selective activity for m asks, eyewear and rubber some essential microbial dam s have lowered the risk of biochemical reaction th a t is not m any potential infectious
REPRESENTATIVE CLASSES OF ORAL ANTISEPTIC AGENTS C la s s
33is-biguanides B is-p y rid in e s H a lo g en s H e a v y m e ta l s a lts H erb al ex tra ct O x y g e n a tin g a g e n ts P h en o lic com p ou n ds P y rim in id es Q u atern a ry a m m on iu m com p ou n ds
preparation as a routine infection control component. W ith th e seven m ajor infec tion control areas m entioned here as a fram ew ork, this procedure would seem to fit best under the heading of aseptic technique. Spirited debate continues, however, as to the efficacy of pre-procedural antim icrobial m outhrinses in this capacity. A lthough a large volume of lite ra tu re has dem onstrated the effectiveness of certain antiseptic m outh rinses in helping to reduce developm ent of gingivitis and periodontitis, th is paper concentrates on th e infection control applications of a pre procedural m outhrinse. These include possible use as a protective m easure for prevent ing endogenous infection in patients and as a useful technique to m inim ize potential cross-infection betw een patients and tre a tm e n t providers. O R A L M IC R O F L O R A AMD O C C U P A T IO N A L R IS K S
The hum an m outh is an ideal incubator for a wide range of potential microbial pathogens,
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an essential reaction of host cells; ■■ be rapidly effective against m icroorganism s; ™ be able to directly kill or inactivate susceptible organism s (th a t is, bactericidal instead of bacteriostatic); “ not induce microbial resistance; ™ be stable and not inactivated by body cells, fluids or infection exudates; “ ■ have a low-surface tension to facilitate penetration, but should not be absorbed by tissues sufficiently to cause local or system ic toxicity; ■■ have a good therapeutic index (th a t is, effective against m icroorganism s a t a concentra tion th a t will not irrita te tissues or interfere w ith tissue healing); " not induce hypersensitivity w ith repeated application; ™ have a residual effect after each use; and ■■ be of reasonable cost for routine use. A lthough a variety of chemical classes have been tested and used as antiseptic m outhrinses, no currently available preparation m eets all of th e foregoing criteria. C H E M IC A L C L A S S E S IN V E S T IG A T E D A S A N T IS E P T IC M O U T H R IN S E S
The search for clinically useful antiseptic agents to assist in controlling th e oral microbial flora is ongoing. Most investi gations have focused on chemo th erapeutic substances th a t affect plaque form ation and gingivitis or periodontitis. Table 2 lists the m ajor classes of antiseptic agents and represen tative compounds for each. (An excellent review5 giving details of properties, m echanism s of 78
JADA, Vol. 123, March 1992
action and efficacy studies appeared in 1988.) R E P R E S E N T A T IV E D A T A S U P P O R T IN G P R E -P R O C E D U R A L A N T IS E P T IC S
Use of pre-procedural a n ti septics is not a recent event, and in fact was advocated years ago. Early studies often involved topical application before injection of local anes thetics, to prevent injection site infections.6 In this study, six preparations were tested. Both 2 percent tincture and aqueous iodines and 2 percent H ibitane (a 2 percent chlorhexidine in alcohol) were found to provide the best antim icrobial activity on oral mucosa. More recently a 0.12 percent chlorhexidine gluconate (CHG) perioperative rinse was shown to clinically reduce the inci dence of alveolar osteitis by 60 percent, w hen compared to placebo controls after surgical removal of im pacted m andib u lar th ird m olars.7 Implications for use of pre-procedural m outh rinses have also been discussed in other studies8 and published guidelines concerning the prevention of infective endocar ditis.910 R esults of a seven-year investigation of p atients with rheum atic h e a rt disease or prosthetic h e a rt valves sug gested th a t rinsing w ith CHG before each dental treatm en t session lessened the chances of bacterem ia by lowering the m icrobial flora concentration.8 The Am erican H eart Assoc iation’s recom m endations for prevention of bacterial endo carditis also address this issue by statin g “... chlorhexidine may be used as an adjunct to a n ti biotic prophylaxis, particularly in patients who are a t high risk and/or have poor dental
ADA MATERIALS
AVAILABLE Q he ADA, through its D epartm ent of Salable M aterials, offers a variety of m aterials designed to help d entists and patients become b e tte r informed on infecton control procedures. These m aterials include: ™ A new eight-m inute p atien t education videotape to assist dentists in com m unicating about infection control procedures used in dental offices. Available M ay 1992. Code: P839; m em b er price: $35. ■■ “Infection Control in the D ental E nvironm ent,” a video and training m anual for th e entire office staff. Code: S548; m em ber price: $75. ™ “Safety and Infection Control M onograph,” inform ation on products for sterilization and disinfection, plus safety and handling precautions for m aterials and equipm ent. Code: S038; m em b er price: $9.95. ™ “F acts About HIV and Infection Control,” a six-page p atien t education pam phlet th a t addresses patient concerns about dental-office infection control procedures. Code: W133; m em ber price: 25/$5.25, 100/$19.95. To order any or all of these item s, contact the D epartm ent of Salable M aterials on its toll-free line: 1(800)947-4746. .
INFECTION
hygiene.”9 We caution however, not to incorrectly in te rp re t this statem en t as a requirem ent for antiseptic m outhrinse use as a component of endocarditis prevention. A nother area of investigation th a t allows for the consider ation of pre-procedural m outh rinses concerns the potential of dental aerosols and spatter droplets to tra n sm it micro organism s. Some dental procedures produce aerosols and sp a tte r th a t can contain microbial concentrations high enough to be considered occupationally hazardous.1112 C haracterization of aerosolized particles and potentially infectious sequelae represents ongoing areas of m edical13 and d e n ta l11,1214 research. Although no commercially available preparation possesses all of th e ideal properties listed previously, 0.12 percent CHG appears to currently demon stra te necessary efficacious characteristics. Its broad antim icrobial effects include significant reductions in the num bers of total aerobes (65 percent to 85 percent reduc tion), anaerobes (42 percent to 80 percent), streptococci (44 percent to 78 percent), and actinomyces (85 percent to 97 percent).15 This study also found th a t repeated rinsing with CHG did not produce a dem onstrable shift in the oral microbial flora. The bis-biguanide th u s did not stim ulate a favorable environ m ent for growth of possible opportunistic microbial species. A subsequent clinical report docum ented an im m ediate and prolonged antim icrobial effect on salivary bacteria after a single 0.12 percent CHG rinse.16 The total anaerobic bacterial population in saliva was
reduced significantly w ithin one m inute after a single rinse with CHG. Additional supporting inform ation for CHG use in controlling potential microbial pathogens was provided when continued analysis of the microbial flora dem onstrated a five-hour antim icrobial effect. The reduction in salivary m icrobial concentration also persisted throughout a 30m inute dental prophylaxis. These clinical d ata were later su b stantiated and expanded to include the effects of two consecutive pre-procedural rinses. Repeated use of 0.12 percent CHG in this m anner had a significant (up to 97 percent reduction) and sus tained effect on the salivary bacterial load.17 Significant reductions in aerobic and facultative bacteria were noted despite th e presence of bioburden such as blood and debris associated w ith scaling and root planing procedures. Virucidal activity has also been dem onstrated in vitro against herpes simplex virus, cytomegalovirus, influenza A, parainfluenza, and hepatitis B viruses in as brief an exposure as 30 seconds.18Poliovirus was not inactivated in vitro, possibly because of the absence of a lipid envelope on the viral surface. Lim ited in vivo data are avail able; however, yet in a t least one study CHG reduced the developm ent of viral lesions and viral titers when applied topic ally onto the skin of herpes simplex virus type 1-infected mice.19 FUTURE C O N S ID E R A T IO N S
Concern about asepsis in the health professions has increased in recent years, in
CONTROL.
p a rt because o documented hazards of disease transm ission and public Dr. John Molinari is anxiety about professor and the perception chairman, Depart ment of Biomedical of risk. D ental Sciences, University care providers of Detroit Mercy School of Dentistry, have 2985 E. Jefferson responded Ave., Detroit 48207. professionally Address reprint requests to Dr. John to the m any Molinari. clinical challenges by im plem enting routine infection control m easures th a t benefit both patients and practitioners. In h eren t in these techniques and protocols is the realization th a t application of infection control principles is dynamic and not static. As new infec tious disease data and s tra te gies for control become avail able, health care workers will have other choices to consider. The use of pre-procedural m outhrinses as a component of a practice’s infection control regim en should be considered in light of scientific progress and unansw ered questions. W ith the exception of fluorides, no group of oral antiseptic agents has received as m uch experi m ental atten tio n as the bisbiguanides. The effectiveness of CHG h as been extensively studied over the past 20 years. W hen the science is viewed in the context of infection control criteria, we notice far more docum ented inform ation to sub stan tiate prevention of endogenous patien t infection th an cross-infection to tre a tm e n t providers. M ultiple applications of CHG have helped to control the onset of opportunistic infections in m any groups of im m une JADA, Vol. 123, March 1992
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compromised individuals, including bone m arrow tra n sp la n t patients, Dr. Gail Molinari is cancer assistant professor and chairman, patients, and Department of HIV-infected Pediatric Dentistry, individuals. University of Detroit Mercy School of Definitive Dentistry. proof demon stra tin g protec tion for dental professionals is m uch more difficult to obtain. Study design m u st face the reality th a t percutaneous sharps injuries to h ealth care w orkers occur interm ittently and are not alw ays noted. Also, the im m une defenses can differ betw een different individuals, thereby causing variation in docum enting specific occupational infections. Such projects would require years of following thousands of subjects, to gath er significant d a ta related to protection from infection. In the m eantim e, the im plications from available d a ta will have to suffice. D ental professionals can weigh the cost of pre-procedural m outhrinsing against potential protective benefits of reducing the spread of m icroorganism s from the p a tie n t’s mouth. But the dental profession has already assum ed major infection control costs. Unless an accommodation is reached w ith other groups, such as th ird-party carriers, the cost of this procedure m ay have to be passed onto patients. P atien t com plaints of bitter ta ste and sta in m ay be placated a fter the infection control rationale for the procedure is
80
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explained to them . While the choice is not a simple one, be rem inded th a t dental personnel have faced greater infection control challenges such as the w earing of gloves and receipt of hepatitis B vaccines. ■ 1. A D A C o u n cils on D e n ta l M a te ria ls a n d D evices; D e n ta l T h e ra p e u tic s . In fe c tio n c o n tro l in t h e d e n ta l office. JA D A 1978;97:673-7. 2. L is te r J . O n th e a n tis e p tic p rin c ip le o f th e p ra c tic e o f su rg e ry . B r M ed J (1867; S e p t 21). 3. C h a n d r a s e k a r P H , M o lin a ri J A . E n d o g e n o u s a n a e ro b e s in o rofacial in fe c tio n s. In fe c t S u rg 1986;5:217-24. 4. ADA R e s e a rc h In s titu te , D e p a r tm e n t o f Toxicology. In fe c tio u s h a z a r d s for b o th d e n ta l p e rs o n n e l a n d p a tie n ts in th e o p e ra to ry . JA D A 198 8 ;1 17:374. 5. M a n d el ID. C h e m o th e ra p e u tic a g e n ts for c o n tro llin g p la q u e a n d g in g iv itis. J C lin P erio d o n to l 1988;15:488-98. 6. C aw so n RA, C u rso n I. T h e e ffe c tiv e n e ss o f som e a n tis e p tic s on th e o ral m u co u s m e m b ra n e . B r D e n t J 1959;208-11. 7. L a rse n P E . T h e effect o f a c h lo rh e x id in e r in s e on th e in cid en ce o f a lv e o la r o s te itis fo llo w in g th e su rg ic a l rem o v a l o f im p a c te d m a n d ib u la r th ir d m o la rs. J O ra l M ax illo fac S u r g 1991;49:932-7. 8. T z u k e rt AA, L e v in er E , S e la M. P re v e n tio n o f in fe c tiv e en d o c ard itis: n o t b y a n tib io tic s alo n e. O ra l S u rg O ra l M ed O ra l P a th o l 1986;62:385-8. 9. D a ja n i AS, e t a l. P re v e n tio n o f b a c te ria l e n d o c a rd itis —rec o m m e n d a tio n s b y t h e A m e ric a n H e a r t A sso ciatio n . JA M A 1990;264:2919-22. 10. B arco CT. P re v e n tio n o f in fe c tiv e e n d o c ard itis: a rev ie w o f t h e m ed ic a l a n d d e n ta l lite r a tu r e . J P e rio d o n to l 1991;62:510-23. 11. M icik R E , M ille r RL, M a z a r r e lla M A, Ryge G. S tu d ie s on d e n ta l aerobiology: 1. B a c te ria l aero so ls g e n e ra te d d u rin g d e n ta l p ro ce d u re s. J D e n t R es 1969;48:49-56. 12. M ille r RL, M icik R E , A b el C, Ryge G. S tu d ie s on d e n ta l aerobiology: II. M ic ro b ia l s p la tte r d isc h a rg e d from th e o ra l c a v ity o f d e n ta l p a tie n ts . J D e n t R es 1971;50:621-5. 13. W e n tzell JM , R o b in so n J K , W e n tz e ll J M J r, S c h w a rtz D E , C a rlso n S E . P h y s ic a l p ro p e rtie s of ae ro so ls p ro d u ce d by d e rm a b ra s io n . A rch D e rm a to l 1989;125:1637-43. 14. R osen S, S c h m a k e l D, S c h o e n e r M. In cid e n c e o f r e s p ira to ry d ise a s e in d e n ta l h y g ie n is ts a n d d ie titia n s . C lin P re v D e n t 1985;7:24-5. 15. B rin e r W W , e t al. E ffe c t o f c h lo rh e x id in e g lu c o n a te m o u th rin s e on p la q u e b a c te ria . J P e rio R es (Suppl)1986;21:44-52. 16. W eeks C, B rin e r W , R e b its k i G , V ick V , F e lle r M . Im m e d ia te a n d p ro lo n g ed effect o f 0.1 2 p e rc e n t ch lo rh e x id in e o n s a liv a ry b a c te ria . J D e n t R es 1988;67:326. 17. V e k s le r A E , K a y ro u z GA, N e w m a n MG. R ed u ctio n o f s a liv a ry b a c te r ia b y p re p ro c e d u ra l rin s e s w ith c h lo rh e x id in e 0.12% . J P e rio d o n to l 1991;62:649-51. 18. B e rn s te in D , e t al. In v itro v iru c id a l e ffectiv en ess o f a 0.1 2 p e rc e n t c h lo rh e x id in e g lu co n a te m o u th rin s e . J D e n t R e s 1990;69:874-6. 19. P a r k J B , P a r k N H . E ffe c t o f c h lo rh e x id in e on th e in v itro a n d in vivo h e rp e s sim p le x v iru s in fectio n . O ra l S u rg O ra l M ed O ra l P a th o l 1989;67:149-53.
