The opinions within this web page are not ours.
Authors have been credited for the individual posts where they are.
- www.rxroots.com photographs courtesy: Marga Ree
From: Marga Ree
To: ROOTS
Sent: Friday, February 25, 2005 4:52 AM
Subject: [roots] Rico, my favourite patient
Today I finished an endodontic treatment on Rico, a 7 year old sweetie. He had an accident 10 months ago with a
uncomplicated crown fracture of teeth # 11 and # 21 and an intrusion of tooth # 11. Within 1 hour his dentist had
repositioned # 11 and applied a semi-rigid splint. He took some pics, unfortunately they are a bit out of focus, and made
2 composite restorations on both central incisors.
A few months after the accident a sinus tract appeared, and he was referred to me. I tried the triple antibiotic soup of
Hoshino, but without succes, the sinus tract didn't disappear. So I decided to do an apical closure with MTA, and after
application of Ca(OH)2 for 1 month the sinus tract did disappear, but there was still a lot of bleeding and draining from
the periapical tissues, so I reapplied the Ca(OH)2 and decided to wait. After 3 more months I was able to make an apical
plug of MTA. The remaining part of the canal was filled with composite. Because of the greyish discoloration of the crown,
I applied some sodium perborate. Today it was his day, I could finally make a definitive restoration. He was very happy
with the result. All together, it took us 7 sessions. I will miss him - Marga
Surprising to see that Hoshino’s soup is not working as he claims 100% success (if I interpret the table correctly) in his
article although on primary teeth.
Are we dealing here with a main difference between primary teeth and permanent teeth or a research project carried out by
the inventor of the soup? In that situation you see that the inventor-researcher often gets the results he wants. Another
argument not to use a product or material till independent research has shown that it may work. Do not go by the results
of the inventor. I cannot see myself work for years on developing a product and then spend the years thereafter my
precious time to proof that my invention does not work.
The lesson to be learned again is: be careful in trusting the results of the inventor!! - Paul Wesselink
Hi Paul,
I for one believe Hoshino to be an honest scientist. And I am also "happy" to see that Ca(OH)2 worked so beautifully when
properly placed by a skilled clinician such as Marga. Besides the antimicrobial effectiveness of Ca(OH)2, its ability to
necrotize remaining tissue within the root canal system will help in the debridement upon the subsequent NaOCl rinse. So
a synergistic effect can be expected to enhance the debridement and disinfection procedure.
As such, I am always surprised by the poor results that some show with Ca(OH)2. I would recommend that before any paper
testing Ca(OH)2 gets published, a proper determination of the material's pH be tested against known controls. - Fred
Paul,
I agree with Fred's remark about Hoshino being an honest scientist. I have no indication of the oppposite,
he is neither a salesman, nor does he want to promote a product in which he has financial interest.
Second remark: what do you loose by trying this triple antibiotic paste to work? Worst case scenario is that it doesn't
work, in which case you can switch to another approach, like I showed with this case. Suppose it did work? I think that
you gain a lot when this immature root will continue to develop in the apical part.
I would try this again in a similar situation, and that has nothing to do with uncritically
trusting the results of the inventor. - Marga
Marga and Fred
I have no reason not believe that Dr Hoshino is an honest researcher but I suggest not to rely on the results of the
inventor as no matter how honest they try to be there is always some bias. Wait for independent research before you start
using these kind of things!
Why did the soup not work in Marga's case while it worked 100% in Hoshino's study.
You may wonder if it is very sensible to expose a child to three antibiotics running the risk to senstize the patient or
contribute to the development of resistant bacteria while you are may be missing a good scientific foundation for your
treatment. What I hate to see is this magic believe in cocktails, drugs and medications in endodontic treatment hoping
that it will help but what is the evidence for their use? No wonder other people start to make up strong antibacterial
cocktails and sell them as a root canal sealer. With this attitude we invite people to do so.If we keep having this
approach in endodontics we remain being hooked up to dressings and medications where the most important part is to remove
that biofilm that is inside the root canal and is probably hardly affected by drugs. - Paul Wesselink
Bravo!!!!! Profesor Wesselink, words of wisdom based in very profound thoughts of somebody who really understands and has
read critically the biology of endodontic therapy., and produced a lot of knowledge in our field.
I salute you again. - Ben
Paul,
Concerns about microbial resistance and sensitization are of course valid.
However, the biofilm was not eradicated by instrumentation and NaOCl. So
what else is to be done? Certainly not surgery! I am sure you would agree
that bleach is a strong cocktail as well, no?
In the perio literature, as far as I remember, doxycycline has not yet
created havoc with resistant strains and allergic reactions. Controlled
release delivery of antimicrobials is especially effective in
reducing/preventing such complications. - Fred
Paul,
I share your concerns with regard to microbial resistance and sensitization,
and in general I agree that there is very limited indication for its use in
endodontics.
However, after reading the below mentioned papers, and especially the paper
of Banchs,
I thought my patient might benefit from this treatment protocol.
Marga
1: Takushige T, Cruz EV, Asgor Moral A, Hoshino E.
Endodontic treatment of primary teeth using a combination of antibacterial
drugs.
Int Endod J. 2004 Feb;37(2):132-8.
PMID: 14871180 [PubMed - indexed for MEDLINE]
2: Hoshino E, Kurihara-Ando N, Sato I, Uematsu H, Sato M, Kota K, Iwaku M.
In-vitro antibacterial susceptibility of bacteria taken from infected root
dentine to a mixture of ciprofloxacin, metronidazole and minocycline.
Int Endod J. 1996 Mar;29(2):125-30.
PMID: 9206436 [PubMed - indexed for MEDLINE]
3: Sato I, Ando-Kurihara N, Kota K, Iwaku M, Hoshino E.
Sterilization of infected root-canal dentine by topical application of a
mixture of ciprofloxacin, metronidazole and minocycline in situ.
Int Endod J. 1996 Mar;29(2):118-24.
PMID: 9206435 [PubMed - indexed for MEDLINE]
4: Banchs F, Trope M.
Revascularization of immature permanent teeth with apical periodontitis:
new
treatment protocol?
J Endod. 2004 Apr;30(4):196-200.
PMID: 15085044 [PubMed - indexed for MEDLINE] - Marga
I apologize for this VERY long posting, but antibiotics are being used in the treatment of periodontal disease:
Fred
1: J Int Acad Periodontol. 2004 Oct;6(4 Suppl):143-9.
The microbiological case for adjunctive therapy for periodontitis.
Page RC.
Regional Clinical Dental Research Center, Health Sciences Bldg., Rm. B-530,
University of Washington, Seattle, WA 98195, USA. roypage@u.washington.edu
That chronic periodontitis is an infectious disease is now firmly established,
and the primary role of Porphyromonas gingivalis, Tannerella forsythensis and
Treponema denticola is generally accepted. Treatment by mechanical means such as
scaling and root planing or surgery generally results in significant clinical
improvement but may not arrest the progress or recurrence of disease. Several
studies have shown that the probability of achieving lasting stability as
measured by the arrest of progressive attachment loss and bone loss by primary
mechanical therapy is a function, in major part, of whether pathogenic
microorganisms are still present at local subgingival sites at the completion of
active therapy. The infecting bacterial species are susceptible to killing by
several antibiotics including, among others, tetracycline-class drugs,
amoxicillin and metronidazole as well as by local exposure to chlorhexidine.
Randomized clinical trials have shown that use of systemically administered
antibiotics as an adjunct to mechanical therapies significantly enhances
clinical outcomes and stability. Several slow-release devices that deliver
anti-microbial drugs directly into periodontal pockets have been developed and
are now on the market. Use of these devices permits local delivery of
long-lasting, high concentrations of doxycycline (Atridox) minocycline
(Arestin), and chlorhexidine (PerioChip) directly into periodontal pockets.
Although these devices differ with regard to ease of use, concentration of drug
delivered and length of time high drug concentrations can be maintained,
randomized clinical trials have shown that their use as an adjunctive treatment
to scaling and root planing results in a significantly greater reduction of
periodontal pocket depth and an average increase in clinical periodontal
attachment level of about 0.8 mm. Gain in clinical attachment is greater in
deeper pockets than in shallower pockets. Locally delivered adjunctive
anti-microbial therapy is an effective means to enhance therapeutic outcomes.
2: Ann Periodontol. 2003 Dec;8(1):79-98.
Local anti-infective therapy: pharmacological agents. A systematic review.
Hanes PJ, Purvis JP.
Department of Periodontics, Medical College of Georgia, School of Dentistry,
Augusta, GA 30912-1220, USA. phanes@mail.mcg.edu
BACKGROUND: It is well recognized that periodontal diseases are bacterial in
nature. An essential component of therapy is to eliminate or control these
pathogens. This has been traditionally accomplished through mechanical means
(scaling and root planing [SRP]), which is time-consuming, difficult, and
sometimes ineffective. Over the past 20 years, locally delivered, anti-infective
pharmacological agents, most recently employing sustained-release vehicles, have
been introduced to achieve this goal. RATIONALE: This systematic review
evaluates literature-based evidence in an effort to determine the efficacy of
currently available anti-infective agents, with and without concurrent SRP, in
controlling chronic periodontitis. FOCUSED QUESTION: In patients with chronic
periodontitis, what is the effect of local controlled-release anti-infective
drug therapy with or without SRP compared to SRP alone on changes in clinical,
patient-centered, and adverse outcomes? SEARCH PROTOCOL: MEDLINE, the Cochrane
Central Trials Register, and Web of Science were searched. Hand searches were
performed of the Journal of Clinical Periodontology, Journal of Periodontology,
and Journal of Periodontal Research. Searches were performed for articles
published through April 2002. In addition, investigators contacted editors of
the above-mentioned journals and companies sponsoring research on these agents
for related unpublished data and studies in progress. SELECTION CRITERIA:
INCLUSION CRITERIA: Studies included randomized controlled clinical trials
(RCT), and case-controlled and cohort studies at least 3 months long.
Therapeutic interventions had to include 1) SRP alone; 2) local anti-infective
drug therapy and SRP; or 3) local anti-infective drug therapy alone. Included
studies had to report patient-based mean values and measures of variation for
probing depth (PD) and/or clinical attachment levels (CAL) for both test and
control groups. EXCLUSION CRITERIA: Studies were excluded if they: 1) included
data from a previously published article; 2) included daily rinsing with
chlorhexidine (CHX); or 3) had unclear descriptions of randomization procedures,
examiner masking, or concomitant therapies. DATA COLLECTION AND ANALYSIS: For
the meta-analysis, PD and CAL were expressed as summary mean effects with 95%
confidence intervals (CI) for the effect, and analyzed using a standardized
difference between SRP alone and experimental agent groups. The results were
assessed with both fixed-effects and random-effects models. Studies were ranked
according to the York system. MAIN RESULTS: 1. Thirty-two studies were included
(28 RCT, 2 cohort, and 2 case-control), incorporating a total patient population
of 3,705 subjects. 2. Essentially all studies reported substantial reductions in
gingival inflammation and bleeding indices, which were similar in both control
and experimental groups. 3. A meta-analysis completed on 19 studies that
included SRP and local sustained-release agents compared with SRP alone
indicated significant adjunctive PD reduction or CAL gain for minocycline (MINO)
gel, microencapsulated MINO, CHX chip and doxycycline (DOXY) gel during SRP
compared to SRP alone. 4. Use of antimicrobial irrigants or anti-infective
sustained-release systems as an adjunct to SRP does not result in significant
patient-centered adverse events. REVIEWERS' CONCLUSIONS: 1. In some populations,
anti-infective agents in a sustained-release vehicle alone can reduce PD and
bleeding on probing (BOP) equivalent to that achieved by SRP alone. 2. No
evidence was found for an adjunctive effect on reduction of PD and BOP of
therapist-delivered CHX irrigation during SRP compared to SRP alone. 3.
Additional RCTs are needed which evaluate the effectiveness of these therapies
in all forms of periodontitis. 4. The study protocol for future RCTs should
include appropriate statistical analyses and complete data sets to facilitate
future evidence-based reviews. 5. Alternative surrogate parameters to PD and CAL
need to be identified and validated such as microbial, inflammatory, or
tissue-destructive markers that could be used in conjunction with clinical
parameters to help determine the patient's response to emerging technologies
that target the infectious and/or inflammatory aspects of periodontitis. 6.
Future Phase IV clinical trials should be designed that evaluate local
anti-infective therapies in conjunction with SRP in a manner consistent with
current standards of care and evaluate cost-effectiveness. 7. The use of local
anti-infective agents in at-risk patient populations and for the treatment of
at-risk disease sites needs to be validated in randomized controlled clinical
trials. 8. Several local anti-infective agents combined with SRP appear to
provide additional benefits in PD reduction and CAL gain compared to SRP alone.
The decision to use local anti-infective adjunctive therapy remains a matter of
individual clinical judgment, the phase of treatment, and the patient's status
and preferences.
3: Ann Periodontol. 2003 Dec;8(1):115-81.
Systemic anti-infective periodontal therapy. A systematic review.
Haffajee AD, Socransky SS, Gunsolley JC.
Department of Periodontology, Forsyth Institute, Boston, Massachusetts, USA.
Ahaffajee@forsyth.org
BACKGROUND: Periodontal diseases are infections and thus systemically
administered antibiotics are often employed as adjuncts for their control. There
are conflicting reports as to whether these agents provide a therapeutic
benefit. RATIONALE: The purpose of this systematic review is to determine
whether systemically administered antibiotics improve a primary clinical outcome
measure, periodontal attachment level change. FOCUSED QUESTION: In patients with
periodontitis, what is the effect of systemically administered antibiotics as
compared to controls on clinical measures of attachment level? SEARCH PROTOCOL:
The Pub/Med database was searched from 1966 to May 2002. Searches were limited
to human studies published in English. Hand searches were performed on the
Journal of Clinical Periodontology, Journal of Periodontology, and Journal of
Periodontal Research. References in relevant papers and review articles were
also examined. SELECTION CRITERIA: INCLUSION CRITERIA: Trials were selected if
they met the following criteria: randomized controlled clinical trials,
quasi-experimental studies, and cohort studies of > 1 month duration with a
comparison group; subjects with aggressive, chronic, or recurrent periodontitis
and periodontal abscess; use of a single or a combination of systemically
administered antibiotics(s) versus non-antibiotic therapy; and a primary outcome
of mean attachment level change (AL). EXCLUSION CRITERIA: Studies involving the
use of low-dose doxycycline, combinations of locally plus systemic antibiotics,
or where the control group included a systemically administered antibiotic were
excluded. DATA COLLECTION AND ANALYSIS: A mean difference in AL between groups
was available for all papers used in the meta-analysis. A standard deviation
(SD) for the difference was used if provided or calculated from the SD or
standard error of the mean (SEM) when provided for single measurements. Data
were subset by antibiotic employed, type of adjunctive therapy, and disease
type. Results were assessed with both fixed-effects and random-effects models.
MAIN RESULTS: 1. Twenty-nine studies, 26 RCTs and 3 quasi-experimental (36
comparisons), met the entry criteria. Total study population, both control and
test groups, was estimated at over 1,200. 2. Twenty-two studies (27 comparisons)
were used in the meta-analysis, evaluating if the antibiotics provided a
consistent benefit in mean AL change for different patient populations, for
different therapies, and for different antibiotics. 3. For the majority of the
comparisons, systemically administered antibiotics exhibited a more positive
attachment level change than the control group in the study. The combined
results were statistically significant (P < 0.001). 4. The systemic antibiotics
were uniformly beneficial in providing an improvement in AL when used as
adjuncts to scaling and root planing (SRP) and were consistently beneficial,
although of borderline significance, when used as adjuncts to SRP plus surgery
or as a stand alone therapy. 5. When examining the effects of individual or
combinations of antibiotics, it was found that there were statistically
significant improvements in AL for tetracycline, metronidazole, and an effect of
borderline statistical significance for the combination of amoxicillin plus
metronidazole. 6. Improvements in mean AL were consistent for both chronic and
aggressive periodontitis subjects, although the aggressive periodontitis
patients benefited more from the antibiotics.
REVIEWERS CONCLUSIONS: 1. The use
of systemically administered adjunctive antibiotics with and without SRP and/or
surgery appeared to provide a greater clinical improvement in AL than therapies
not employing these agents. 2. The data supported similar effect sizes for the
majority of the antibiotics; therefore, the selection for an individual patient
has to be made based on other factors. 3. Due to a lack of sufficient sample
size for many of the antibiotics tested, it is difficult to provide guidance as
to the more effective ones.
4: J Clin Periodontol. 1998 May;25(5):354-62.
The use of metronidazole and amoxicillin in the treatment of advanced
periodontal disease. A prospective, controlled clinical trial.
Berglundh T, Krok L, Liljenberg B, Westfelt E, Serino G, Lindhe J.
Department of Periodontology, Faculty of Odontology, Goteborg University,
Sweden. berglund@odontologi.gu.se
The present clinical trial was performed to study the effect of systemic
administration of metronidazole and amoxicillin as an adjunct to mechanical
therapy in patients with advanced periodontal disease. 16 individuals, 10 female
and 6 male, aged 35-58 years, with advanced periodontal disease were recruited.
A baseline examination included assessment of clinical, radiographical,
microbiological and histopathological characteristics of periodontal disease.
The 16 patients were randomly distributed into 2 different samples of 8 subjects
each. One sample of subjects received during the first 2 weeks of active
periodontal therapy, antibiotics administered via the systemic route
(metronidazole and amoxicillin). During the corresponding period, the 2nd sample
of subjects received a placebo drug (placebo sample). In each of the 16
patients, 2 quadrants (1 in the maxilla and 1 in the mandible) were exposed to
non-surgical subgingival scaling and root planing. The contralateral quadrants
were left without subgingival instrumentation. Thus, 4 different treatment
groups were formed; group 1: antibiotic therapy but no scaling, group 2:
antibiotic therapy plus scaling, group 3: placebo therapy but no scaling, group
4: placebo therapy plus scaling. Re-examinations regarding the clinical
parameters were performed, samples of the subgingival microbiota harvested and 1
soft tissue biopsy from 1 scaled and 1 non-scaled quadrant obtained 2 months and
12 months after the completion of active therapy. The teeth included in groups 1
and 3 were following the 12-month examination exposed to non-surgical
periodontal therapy, and subsequently exited from the study. Groups 2 and 4 were
also re-examined 24 months after baseline. The findings demonstrated that in
patients with advanced periodontal disease, systemic administration of
metronidazole plus amoxicillin resulted in (i) an improvement of the periodontal
conditions, (ii) elimination/suppression of putative periodontal pathogens such
as A. actinomycetemcomitans, P. gingivalis, P. intermedia and (iii) reduction of
the size of the inflammatory lesion. The antibiotic regimen alone, however, was
less effective than mechanical therapy with respect to reduction of BoP -
positive sites, probing pocket depth reduction, probing attachment gain. The
combined mechanical and systemic antibiotic therapy (group 2) was more effective
than mechanical therapy alone in terms of improvement of clinical and
microbiological features of periodontal disease.
5: J Clin Periodontol. 2004 Oct;31(10):869-77.
Clinical and microbiological changes associated with the use of combined
antimicrobial therapies to treat "refractory" periodontitis.
Haffajee AD, Uzel NG, Arguello EI, Torresyap G, Guerrero DM, Socransky SS.
Department of Periodontology, The Forsyth Institute, Boston, MA, USA.
ahaffajee@forsyth.org
BACKGROUND: The present investigation examined clinical and microbial changes
after a combined aggressive antimicrobial therapy in subjects identified as
"refractory" to conventional periodontal therapy. METHOD: Fourteen subjects were
identified as "refractory" based on full-mouth mean attachment loss and/or >3
sites with attachment loss > or =3 mm following scaling and root planing (SRP),
periodontal surgery and systemic antibiotics. After baseline monitoring,
subjects received SRP, locally delivered tetracycline at pockets > or =4 mm,
systemically administered amoxicillin (500 mg, t.i.d. for 14 days)+metronidazole
(250 mg, t.i.d. for 14 days) and professional removal of supragingival plaque
weekly for 3 months. Subjects were monitored clinically every 3 months
post-therapy for 2 years. Subgingival plaque samples were taken at the same time
points from the mesial aspect of each tooth and the levels of 40 subgingival
taxa were determined using checkerboard DNA-DNA hybridization. Mean levels of
each species were averaged within a subject at each visit. Significance of
changes in clinical and microbiological parameters over time were evaluated
using the Friedman or Wilcoxon signed ranks test. RESULTS: On average, subjects
showed significant improvements in all clinical parameters after therapy. Mean
(+/-SEM) full-mouth pocket depth reduction was 0.83+/-0.13 mm and mean
attachment level "gain" was 0.44+/-0.12 at 24 months. Clinical improvement was
accompanied by major reductions in multiple subgingival species during the first
3 months of active therapy that were maintained for most species to the last
monitoring visit. Reductions occurred for three Actinomyces species, "orange
complex" species including Campylobacter showae, Eubacterium nodatum, three
Fusobacterium nucleatum subspecies, Peptostreptococcus micros, Prevotella
intermedia as well as the "Streptococcus milleri" group, Streptococcus
anginosus, Streptococcus constellatus and Streptococcus intermedus. Subjects
differed in their response to therapy; six modest response subjects exhibited
less attachment level gain and were characterized by reductions in the
microbiota from baseline to 3 months, but re-growth of many species thereafter.
CONCLUSIONS: The combined antibacterial therapy was successful in controlling
disease progression in 14 "refractory" periodontitis subjects for 2 years.
Copyright Blackwell Munksgaard, 2004
Dear Paul,
have a question!
Somebody approached me telling me the story of the PCR checkerboard test in
Perio. He than asked me why not doing the same in Endo.
I asked him: where would the great benefit be? Who can pay for?
His answer: You will know when the root canal filling is indicated!
Let me just put this short conversation in the air and wait for suggestions,
comments, of course critique and please lots of advises! - Liviu
Dear Liviu.
Do you mean this type of work?
I glanced over it last night. It seems as certain strains can grow in the presence of calcium hydroxide? Or at least ther
was a moderate increase in the prevalence of A actinomycetemcomitans, E corrodens and E nodatum. Where have I seen
increased prevalence or growth of mico-organisms in the presence of calcium hydroxide before? . At least E. faecalis was
gone after treatment in primary endodontic infections with sodium hypochlorite and calcium hydroxide.
But may be I should take the time to read it better.
I hope this information helps you and is what you were asking for - Paul Wesselink
Honesty has nothing to do with bias when you are the inventor. Actually Dr. Hoshino is not the clinician in the reported
studies with almost 100%.success.. He is certainly the world expert in Carious Dentin and therefore of bacteria in the
tubules. The use for revascularization came later, he was looking for a mix to disinfect dentin.
I certainly have been fascinited with his work. as it was an area of research interest for me.
Below are abstract of some of the studies not about re-vascularization but disinfection of dentin, including the one on
"anti-freeze" polypropilen glycol. Glicol de propileno in Spanish ... I did some pilot work 25 years ago mixing an acetate
salt of Chlorexidine (not gluconate but acetate) in carious dentin, we also mixed CHX with polycarboxilate, there was a
paper by Schwartzman, Caputo on this in J. Prost. dentistry.Boris worked in our lab in Mexico as an undergrad. and took
the idea to UCLA where he studied for his Prsth. specialty, he got Dr. Caputo a materials science man into the idea.
Schwartzman, B., A. A. Caputo, et al. (1980). "Antimicrobial action of dental cements." J Prosthet Dent 43(3): 309-12.
It was observed that some of the cements tested had bacteriostatic and/or bactericidal action. The cements listed in
decreasing order of effectiveness are (1) zinc oxide-eugenol, (2) silicophosphate, (3) zinc phosphate, and (4) silicate.
The two newer cements, polycarboxylate and composite resin, exhibited no measurable antimicrobial action.
Schwartzman B, Caputo AA
Enhancement of antimicrobial action of polycarboxylate cement.
In: J Prosthet Dent (1982 Aug) 48(2):171-3
Hoshino, E., N. Kurihara-Ando, et al. (1996). "In-vitro antibacterial susceptibility of bacteria taken from infected root
dentine to a mixture of ciprofloxacin, metronidazole and minocycline." Int Endod J 29(2): 125-30.
The aim of this study was to clarify the antibacterial effect of a mixture of ciprofloxacin, metronidazole and
minocycline, with and without the addition of rifampicin, on bacteria taken from infected dentine of root
canal walls. The efficacy was also determined against bacteria of carious dentine and infected pulps which may
the precursory bacteria of infected root dentine. This efficacy was estimated in vitro by measuring bacterial
recovery on BHI-blood agar plates in the presence or absence of the drug combination. Bacteria ranging in
number from 10(2) to 10(6) occurred in samples of infected root dentine (27 cases). However, none was
recovered from the samples in the presence of the drug combination at concentrations of 25 micrograms ml-1
each. The respective drug alone (10, 25, 50 and 75 micrograms ml-1) substantially decreased the bacterial
recovery, but could not kill all the bacteria. Bacteria taken from carious dentine (25 cases) and infected
pulps (12 cases) were also sensitive to the drug combination. These results may indicate that the bactericidal
efficacy of the drug combination is sufficiently potent to eradicate bacteria from the infected dentine of
root canals.
Hori, R., S. Kohno, et al. (1997). "Bactericidal eradication from carious lesions of prepared abutments by an
antibacterial temporary cement." J Prosthet Dent 77(4): 348-52.
PURPOSE: The aim of this study was to observe the antibacterial potential of polycarboxylate temporary cement
containing a mixture of metronidazole, ciprofloxacin, and cefaclor on carious lesions of prepared abutments
that were designed to leave caries on the abutments. MATERIAL AND METHODS: Antibacterial efficacy was
estimated in vitro and in vivo by measuring bacterial recovery from the lesions. Bacteria counts ranged from
10(4) to 10(7) both in vitro (nine samples) and in vivo (five samples) in time-zero samples, just before the
application of the antibacterial cement. RESULTS: No bacteria were recovered from carious lesions in vitro
(six samples) or in vivo (four samples) after the lesions were covered by the antibacterial temporary cement.
For the remaining samples, some bacteria (5 to 80 counts per sample) were recovered, with one notable
exception in which marginal leakage provided a bacteria count of 10(3). Bacteria counts ranging from 10(3) to
10(5) occurred in carious lesions covered by temporary cement without antibacterial agents, which indicated
that temporary cement alone was not a potent disinfectant. CONCLUSIONS: The results of this study indicated
that the antibacterial temporary cement can be useful for eradicating bacteria from carious lesions of
prepared abutments.
Cruz, E. V., K. Kota, et al. (2002). "Penetration of propylene glycol into dentine." Int Endod J 35(4): 330-6.
AIM: This study aimed to evaluate penetration of propylene glycol into root dentine. METHODOLOGY: Safranin O
in propylene glycol and in distilled water were introduced into root canals with and without artificial smear
layer. Dye diffusion through dentinal tubules was determined spectrophotometrically. The time required for dye
to exit through the apical foramen using propylene glycol and distilled water as vehicles was also determined.
The extent and areas of dye penetration on the split surfaces of roots were assessed using Adobe Photoshop and
NIH Image Software. RESULTS: Propylene glycol allowed dye to exit faster through the apical foramen. The area
and depth of dye penetration with propylene glycol was significantly greater than with distilled water (P <
0.0001). Smear layer significantly delayed the penetration of dye. CONCLUSION: Propylene glycol delivered dye
through the root canal system rapidly and more effectively indicating its potential use in delivering
intracanal medicaments.
Ben posted this abstract bt Hoshino's group previously:
Int Endod J. 1998 Jul;31(4):242-50.
Bacterial eradication from root dentine by ultrasonic irrigation with sodium
hypochlorite.
Huque J, Kota K, Yamaga M, Iwaku M, Hoshino E.
Department of Operative Dentistry and Endodontics, Niigata University School of
Dentistry, Japan.
The study aimed to evaluate intracanal irrigation procedures in eradicating
bacteria from surface, shallow and deep layers of root dentine using extracted
human teeth. Artificial bacterial smear layer was successfully produced by
rubbing a mixture of dental plaque and artificially decalcified dentine or
carious dentine on root canal walls. The reservoir holes were 3.5 mm in depth, 1
mm in diameter prepared 1.5 mm apart and parallel to the root canals on the
decrowned planes, in which five separate bacterial species were placed
(Actinomyces israelii, Fusobacterium nucleatum, Propionibacterium acnes,
Streptococcus mutans and Streptococcus sanguis). Bacterial eradication after
irrigation of the prepared canals was determined by bacterial recovery (i) from
the root canal surfaces and shallow layers where bacteria were smeared
artificially and (ii) from deeper layers of root canal dentine reservoir holes.
Ultrasonic irrigation with 5.5% and 12% NaOCl eradicated bacteria from
artificial smear layer (P < 0.0001), whilst 12% NaOCl irrigation with a syringe
was insufficient. Ultrasonic irrigation with water or 15% EDTA-failed to
eradicate bacteria from smeared surfaces. Ultrasonic irrigation with 12% NaOCl
killed A. israelii, F. nucleatum, P. acnes, S. mutans, and S. sanguis placed in
reservoir channels, although for F. nucleatum, a very small number of bacteria
remained in five samples out of 12. Ultrasonic irrigation with less concentrated
NaOCl failed to eliminate bacteria completely from reservoir channels in most
samples. Ultrasonic irrigation with 12% NaOCl appeared to eliminate bacteria
efficiently from surface, shallow and deep layers of root dentine.
Fred, My first time posting to this group although I have appreciated what I have read so far.
I graduated from dental school in 1997, and at that point, what we were taught in the endo clinic
was mix the calcium hydroxide powder with "pretty much any sterile liquid"...we used sterile water,
sterile saline or even lidocaine. And now you are saying, maybe the pH is important??? :) Well,
that's going to change if you are using these different liquids. It would also change depending on
the viscosity of the mix, true? i.e., more or less calcium hydrox:water ratio?
Could this explain why it works so well for some, but not for others?
You mean everything I learned in dental school isn't engraved in stone? - CATHERINE JOHNSON MINCY, DDS
If you mix Ca(OH)2 USP powder with local anesthetic, the pH is still very
high; and works clinically.How do I know.......I have used it that way for
years......see, clinical empiricism ;-)) Same goes for CHX.
The high pH accounts for the antimicrobial effectiveness as most of the
canal bugs are not alkalinophilic. Of course, E. faecalis, the famous bug,
can survive in a pH of at least 10. This bug can neutralize its cytoplasm
via proton pumps. See papers by David Figdor et al. - Fred
Hi Fred ,
abpout 15 years ago, I started to use Ca(OH)2 because the lit suggested
to do so and because Ledermix/Aphaline was not considered chemically
correct although it worked fine. As a consequence, I had a lot of
flareups and went back to my old L/A. It was several years later that I
took a course with Oliver Pontius who showed single visit endo in
necrotic teeth using lots of NaOCl for irrigation and emphasizing the
importance of patency (a term I had never heard of before) and
suggesting Ca(OH)2 as a dressing. I retried with higher concentrations
of NaOCl and longer rinsing and patency and Ca(OH)2 as an interdediate
dressing and - big surprise - Ca(OH)2worked fine all of a sudden.
I did not need the L/A any more. My gut feeling from these experiences
is that you have to clean the canal to the foramen, dissolve the tissue
with NaOCl and then and only then Ca(OH)2 will work predictably in
necrotic cases. Vital cases are a different story.
Back in those early L/A days, my problem were vital teeth with pulps
bleeding like hell and widened pdl. Necrotic cases with big
translucencies worked a lot better. Looking back I interpret this
problem as lack of dissolving the tissue with NaOCl, giving neither
Ca(OH)2 nor L/A a chance to reach the problem. Does that make sense to you? - Winfried
Winfied, Exactly! You get it. Nonspecific agents, bleach, CH, and Chlorhexidine
work just fine and the most clinically significant and variable part of
the process is the mechanical debridement that allows access of these
agents. The obsession with specific antimicrobial concoctions like
Ledermix fails to address the weakest link of the treatment process
contributing to success or failure which is the variable operator level
and ability to skillfully "clean and shape". - Terry
It certainly makes sense to me, Winfried. CaOH is a cauterizing agent. It works on contact.
The only reliable Tx is C&S to completion, plus CaOH which will then make contact
where "the rubber meets the road". DougR
Hi Winfried,
Yes, it does make some sense to me. The Ca(OH)2 has to get to the problem
area to work best. Minimal debridement of a canal, and then trying to get
the white stuff down there and expecting good results does not work.
I did a study at Penn on 2000 teeth, looking at flare-ups (never published
but presented at the IADR). 1000 teeth were from the postdoc clinic and
1000 teeth were from my practice over a period of time. We did NOT practice
patency, but, the canal was COMPLETELY DEBRIDED to 0.5 to 1mm short of
radiographic apex with diluted NaOCl, and then filled with Ca(OH)2 powder
mixed with either sterile water or LA solution.
Asymptomatic teeth had a flare-up rate of about 2.5%.
Silver point retreatments : ~10%. - Fred