Review Article
Single - visit endodontics - A review
Dr. Nandakishore K J*
Dr. Shija A S*
Dr. Vinaychandra R**
Today knowledge is power. It controls the access to opportunities and
advancement. Advancement has occurred in all fields and dentistry is not an
exception. Single sitting root canal therapy is an outcome of such newer
advancements.
Abstract
This article presents a review on single-visit
endodontics. With the present fast paced life that
everyone leads, it is a must for every dentist practicing
endodontics to be aware of when, how and with what
means to successfully complete root canal treatment in
a single-visit. This article will also help dispel some
myths regarding single-visit endodontics. With the
introduction of newer instruments and techniques, it is
much easier today to successfully perform single-visit
endodontics.
Keywords : Asymptomatic Nonvital Pulps, Periradicular
surgery, Acute apical periodontitis, Anatomic
anomalies, Chemical debridement
* Senior Lecturer, ** Reader, Department of
Conservative Dentistry and Endodontics,
RajaRajeswari Dental College and Hospital.
Bangalore.
Correspondence: Nandakishore K J, Senior Lecturer,
Department of Conservative Dentistry and Endodontics,
RajaRajeswari Dental College and Hospital,
Kumbalgodu, Mysore Road,
Bangalore - 560074.
Email id: [email protected]
One visit endodontics is defined as “the conservative non surgical treatment of
an endodontically involved tooth consisting of complete biomechanical
cleansing, shaping, and obturation of the root canal system during one visit”.1
“Maximum dentistry in minimum visits” has been the rule in modern dental
practice. The concept of doing complete endodontic treatment in one visit is
not new. It was there from at last 100 Years. Although the concept remained
constant, the technique varied.
However, only recently the beliefs and attitudes concerning the inclusion of
this technique into practice of clinical endodontics appear to be undergoing a
process of change, because of expanding favorable clinical experience and an
increasing number of favorable clinical research studies, single sitting
endodontics has moved away from being an empirical technique. It is now
viewed as an acceptable treatment procedure for certain specific endodontic
problems.
Guidelines for Single-Visit Endodontics
Success in endodontic therapy is based on:
1. Accurate diagnosis
2. Proper case selection
3. Use of skilled techniques of treatment
Preliminary Considerations
Operator Ability and Clinical Experience
It is a technique for experienced practitioners who have made endodontics an
integral part of their clinical practices and not for the person who only does an
occasional endodontic case. Once endodontics is done routinely and with
satisfactory results, the practitioner should make a careful assessment as to
how long it takes to thoroughly cleanse, shape, and fill the root canal systems of
anterior and posterior teeth, utilizing conventional multivisit procedures. The
clinician will then know the time that is necessary to perform a complete
treatment on any tooth in the mouth and can schedule his or her one-visit
procedures accordingly.
Time and Auxiliary Utilization
It should be remembered that one-visit endodontics is dependent upon the
use of fundamental endodontic operative skills. There are no short cuts, simply
the application of these skills in a thoughtful and organized manner. A failure to
develop these basic skills to a high degree of competence can only result in a
high incidence of broken instruments, ledged canals, perforations,
inadequately prepared and incompletely filled root canals.
Clinical criteria
It should be remembered that one-visit endodontics is dependent upon the
use of fundamental endodontic operative skills. There are no short cuts, simply
the application of these skills in a thoughtful and organized manner.
23
Journal of Health Sciences and Research, Volume 2, Number 1, April - 2011
Review Article
A failure to develop these basic skills to a high degree of
competence can only result in a high incidence of broken
instruments, ledged canals, perforations, inadequately prepared
and incompletely filled root canals.
designed restoration. In each and every instance treatment
can be planned ahead of time and endodontic treatment
can be completed in one visit.
4. Vital Pulp Exposures and Symptomatic Pulpitis
Systemic Evaluation and Premedication
A history of myocardial infarction within the past six months is
contraindicated for elective dental treatment. These patients
should be treated with a stress reduction protocol which includes
short appointments, psychosedation and pain and anxiety
control. Patients with a history of rheumatic heart disease should
be premeditated with amoxicillin, erythromycin or clindamycin,
as per the current “American Heart Association Guidelines”.
Teeth containing vital pulp could include teeth with pulp
exposures caused by trauma, caries, or mechanical reasons
and teeth that exhibit clinical symptoms to heat or cold
stimuli but not percussion.
In cases of vital pulp, a single–visit treatment should be used
whenever possible. This is based on the fact that the pulp is
only superficially infected and the root canal is free of
bacteria, provided the aseptic chain is maintained during
the intracanal procedures. Therefore, there is no apparent
reason not to treat vital pulp in single visit.
Specific Case Selection
Oliet's Criteria for Case Selection3
5. Asymptomatic Nonvital Pulps
1. Positive patient acceptance.
2. Sufficient available time to complete the procedure properly.
Absence of any acute symptoms requiring drainage via the
3. canal and of persistent continuous flow of exudate or blood.
Absence of anatomical obstacles like calcification in the
4. canals, and procedural difficulties (ledge formation, blockage,
perforation, inadequate fills).
This particular indication is probably the most controversial
in terms of whether or not a one-visit procedure can be
performed without an increased incidence of postoperative
pain. Teeth with non vital pulps plus an associated sinus
tract appear to be the least likely to cause postoperative
discomfort.
6. Patients who are physically unable to return for the
completion.
Indications 4,5,6
1. Isolation and Sealing Problems
There are certain instances when a one-visit procedure can be
used to eliminate the potential problem of inter-appointment
contamination and/or flare-ups due to leakage or complete
loss of the temporary seal.
2. Anterior Esthetic Problems
7. Patients who require sedation or operating room
treatment.
8. Immediate periradicular surgery
9. Dentist skill
Contraindications 7-11
Cases falling into this category would be maxillary anteriors
involved in trauma that have resulted in a horizontal fracture
of the crown at the gum line. These cases are probably the
most frequently treated in one visit and pose esthetic as well
as isolation and sealing problems if treated in the
conventional multi-visit manner. At the completion of
3. Restorative Considerations
Cases that fall into this category require endodontics for
restorative reasons and not because they have pathologic
pulp tissue that must be removed or because of pulp
exposures. Examples would include teeth to be used as
overdenture abutments, mandibular anteriors to be cut down
for full jacket crowns, teeth with severe coronal breakdown
that cannot possibly retain a restoration because of the severe
loss of tooth structure, and teeth that require preparation
that would result in pulp exposure in order to get them into a
certain desired alignment for the construction of a specifically
1.
2.
3.
4.
5.
6.
7.
8.
9.
Cellulitis
Acute apical abscess requiring incision and drainage
Severe pain when the tooth is lightly touched
A weeping canal that cannot be dried
Difficult cases that extend beyond our allotted time and the
patient's tolerance
Patients with acute apical periodontitis
Molars with necrotic pulps and periradicular radiolucencies
Symptomatic Root canal retreatment
Patients with TMJ disorders and inability to open the mouth
Conditions where multiple visit therapy is
preferred over single visit therapy7
1. Asymptomatic nonvital teeth with periapical pathology and
no sinus tract
2. Teeth with anatomic anomalies
Journal of Health Sciences and Research, Volume 2, Number 1, April - 2011
24
Review Article
3. Infected cases with evidence of apical periodontitis
(periapical radiolucency, swelling, exudates).
4. Patients with many allergies or previous flare-ups.
Postoperative pain is greater when endodontic therapy is completed in
a single visit, especially in nonvital teeth.
Fact No.1:
7
Advantages
1. It reduces patient appointment visits per tooth while still
maintaining a traditionally predictable high level of
treatment.
2. It eliminates inter-appointment contamination and flare-ups
due to leakage or loss of the temporary seal in severely
broken-down teeth.
3. It allows the practitioner to immediately use the canal for
retention of a post to construct an esthetic temporary crown
in maxillary anterior trauma cases in which the crown has
been fractured off to the gum line.
4. It allows the practitioner to fill the canal when he or she is
most familiar with the canal anatomy, working length, and
position of the apical stop.
5. As the treatment is completed in a single-visit, it allows the
dentist to pass on the savings of chair time in the form of a
reduction in fee to the patient.
Overwhelming evidence shows that postoperative pain resulting from
treatment of vital or nonvital teeth does not differ among patients
treated in a single visit or in multiple visits.12
Myth No.2:
There is less healing when endodontic therapy is completed in a single
visit, especially in non-vital tooth.
Fact No.2:
Comparative studies have produced no statistical difference between
healing of vital and nonvital teeth treated in single or in multiple visit.12
Myth No.3:
Post operative swelling is greater when endodontic therapy is
completed in a single visit.
Fact No.3:
1,4,9
Disadvantages
1. For those practitioners who culture the root canal microflora,
this check on the effectiveness of their biomechanical
preparation would be missing from the treatment regimen.
2. Clinician fatigue with extended one-appointment operating
time
3. Patient fatigue and discomfort with extended operating time.
4. No opportunity to place an intracanal disinfectant (other than
allowing NaOCl to disinfect during treatment).
5. Inability to control exudate may prevent completion of the
procedure.
12
Myths Associated With Single-Visit Endodontics
For many years, dentists have practiced single-visit
endodontics (initiating and completing root canal treatment in
one appointment) on vital and nonvital teeth. However, a
significant number of clinicians do not perform single visit
treatment for various misconceptions.
There are three major reasons that patients once refused
endodontic treatment and often chose tooth extraction
instead: cost, fear of pain, and time. These are three reasons to
perform single-appointment treatment. For single-visit
procedures, less time and materials are required. With so many
advantages and few disadvantages, why don't more clinicians
practice single-appointment endodontics? Reasons include
widespread belief in myths associated with such treatment.
25
Myth No.1:
Trope defined flare-up as "intolerable pain and/or swelling". Using a
similar definition, Walton and Found studied data from 946 patients'
visits for treatment of vital and nonvital teeth, and found no significant
difference in flare-ups between single-and multiple-visit endodontics
(no inter-appointment medicaments were used). 12
Myth No.4:
Canals are cleansed if an antibacterial medicament such as Ca(OH)2 is
left in the root canal and a later appointment is given for permanent
root canal filling.
Fact No.4:
Prolonging treatment to multiple appointment, leads to bacterial regrowth in canals, with or without most inter-appointment
medicaments, including Cresantine, phenols, and polyantibiotics. On
the Other hand, if multiple appointments are necessary, Ca(OH)2 has
been shown to be an effective inter-appointment antibacterial
medicament.12
Myth No.5:
Multiple-visit endodontics is safer than single-visit endodontics, and
multiple visits mean more careful treatment.
Fact No.5:
Goerig and Neaverth summed it up best: Recent studies have shown no
difference in the quality of treatment, incidence of post treatment
complications, or success rate when comparing single-visit with
multiple-visit root canal treatment.12
Journal of Health Sciences and Research, Volume 2, Number 1, April - 2011
Review Article
Myth No.6:
Patients do not mind multiple appointments and are likely to object to the
fee if the procedure is completed in a single visit
Fact No.6:
Aside from cost, there are two other major barriers to patients visiting
the dentist: fear of pain and time required. Completing root canal
therapy in one appointment limits fear of pain to one incidence and
decreases the time required (the number of appointments and total
treatment time). Patients are more likely to, accept single-visit
treatment.
Dentists may think that single-visit endodontics should cost less than
multiple-visit endodontics; on the contrary, patients may pay a premium
for more efficient treatment. Nonstop flights often cost more than
indirect flights and overnight mail costs more than regular delivery. We
live in a fast-paced society. Patients want efficient, high-quality care, and
usually are willing to pay a reasonable fee for it.12
Myth No.7:
After obturation, treating a flare-up is complicated; therefore, treatment
should not be completed at the first appointment.
predictable root canal shaping. The rotary technique is less
fatiguing for the practitioner and NiTi decreases
postoperative pain for the patient, most likely due to a
combination of file design and a crown-down modality.
Eg: Pro Taper Files, Light Speed, Greater Taper Files, Hero
shaper, Profile, K3, Race
Because rotary systems reduce treatment time, single visits
are now within the reach of most practitioners. However,
speed alone does not justify single-visits. It is meticulous
canal cleaning and disinfection that does.
2. Microscopes
The introduction of the microscope to the field of
endodontics has provided the clinician an opportunity to
observe areas of interest at high magnification under
constant illumination. The use of this device during root
canal treatment can assist the clinician in locating and
negotiating calcified canals, and performing surgical and
nonsurgical root canal treatments.
3. Chemical debridement 14-19
Fact No.7:
Fear of a post-obturation flare-up prevents clinicians from performing
single-visit endodontics, but such flare-ups generally are less common
than inter-appointmentflare-ups. The flare-up rate associated with
single-visit endodontics is the same as that associated with multivisit
endodontics. Flare-ups after single-visit treatment are treated exactly
the same way as post-obturation flare-ups after multi-visit treatment.
Most flare-ups can be treated with occlusal reduction, analgesics, and
antibiotics. In the unusual event that a problem continues, apical
trephination (fistulization) can be performed. If the canals are cleaned
and filled properly, a need to remove filling material is rare. Whether
obturation is performed in a single visit or after multiple visits, removal of
gutta-percha (if necessary) usually is straight forward.12
Single Visit Endodontic Therapy And Recent
Advances
Over the past decade, nickel titanium rotary instrumentation,
microscopic endodontics, digital radiography, a plethora of
obturation systems, and biocompatible sealing materials have
helped practitioners perform endodontic procedures more
effectively and efficiently than ever before. This is not implying
that endodontic treatment has become easier; however, better
tools and technology have made it more predictable and
challenge us to take on a wider variety of complex cases.
1. Nickel Titanium rotary instrument & crown down
technique13
The introduction of nickel titanium, or NiTi, rotary
instrumentation has made endodontics easier and faster
than hand instrumentation, resulting in consistent and
While it can reduce the bacterial count significantly,
mechanical debridement does not disinfect the root canal
system completely. Thus, a root canal irrigant is needed to
aid in the debridement of the canals. Sodium hypochlorite
(NaOCl) is the most commonly used root canal irrigant.
However, NaOCl has some major shortcomings, including its
inability to remove the smear layer and to kill all bacteria
present in infected root canals.
Chlorhexidine, an antimicrobial agent with strong affinity to
dental hard tissues is used as an irrigating solution because
it would be retained and would contribute to the
maintenance of a bacteria free root canal for some time
after completed endodontic therapy.
Smear layer removal is best achieved by irrigating the canal
system with NaOCl throughout the chemo mechanical
preparation procedure to prevent accumulation of debris on
the canal walls and to flush out the canal system. A final rinse
with 17.5% ethylene diamine tetra-acetic acid (EDTA) is
recommended for removal of the inorganic component.
Recently, a mixture of a tetracycline isomer, an acid and a
detergent known as MTAD has been introduced as a final
rinse for disinfection of the root canal system. This irrigant is
able to remove the smear layer safely, and it is a more
effective disinfectant than NaOCl even against resistant
bacteria such as E. faecalis.
Journal of Health Sciences and Research, Volume 2, Number 1, April - 2011
26
Review Article
4. Electronic apex locators
The task of determining canal length has moved into a new
and more precise era with the rapid evolution of electronic
devices that measure the length of the root canal. Research
and clinical experience support the claim that apex locators
can assist accurately in determining canal length in the
majority of cases.
Electronic apex locators work on the principles of resistance,
impedance and frequency. Recent apex locators (Root ZX,
AFA, Justy, Endex- Plus) have been reported to be accurate to
within 0.5 mm in >90% of cases.
They reduce not just the radiation dosage, but are also helpful
in quick determination of working length.
5. Obturation systems
Successful single-visit treatment depends on effective
mechanical debridement, chemical disinfection, and proper
sealing of the canal system. Obturation can only be as good as
the instrumentation, since filling material cannot occupy the
same space as the debris left by poor instrumentation.
Researchers have attributed failure of root canal therapy
largely to incomplete obturation of the root canal system.
Injectable thermoplasticized techniques have been found to
be not just time saving, but they also produce dense, well
obturated root canal systems.
Eg: Obtura II, Thermafil, One Step Obturators, E and Q System.
6. Digital Radiography
It is a computerized imaging system that uses an electronic sensor
instead of an X-ray film. They are helpful in achieving a successful
single-visit endodontic therapy by the following means,
1.
2.
3.
4.
Yielding sharp, clear images
Using 70% less radiation than conventional X-ray film
Image appearing rapidly on a computer screen
It is quick and has the added ability to zoom in on a specific
area on the radiograph.
5. The resolution and diagnostic quality is excellent, storage is
easy and there are no developing or processing errors.
7. Ultrasonics
Recent studies have shown ultrasonics to be superior in
debriding the root canal system when compared with hand
instruments. The irrigating solution used with ultrasonics was
sodium hypochlorite 2.5%. The ultrasonics used with small file
held free of the canal walls, warms the solution in the canal and
27
resonant vibrations cause movement of aqueous irrigants;
an effect called Acoustic microstreaming.
According to many studies, the use of ultrasonics will result
in few cases of post operative pain compared to the cases
done with hand-instrumentation.
Conclusion
A generation ago, dentists were taught to culture canals before
obturating them and the idea of single-visit endodontics was
unheard of. Multiple medicaments and intracanal antibiotics
were the generally accepted standard of care. Presently, singlevisit endodontics is widely accepted and practiced.
In the present times, everyone leads a fast-paced life. No
patient would like to come to a clinic several times to get a single
tooth root canal treated. A quick, efficient and well done root
canal therapy in a single appointment will be well appreciated.
It is advantageous to both the patient and dentist in many ways.
Single-visit endodontics can be practiced by a dentist who is
well versed with root canal therapy, provided the dentist is fully
aware of the indications and contraindications of single-visit
endodontic therapy. It is important to note that there is no short
cut to success; single-visit endodontics does not mean skipping
of any step, rather all the steps must be systematically
performed to achieve a successful outcome. To conclude, one
must bear in mind that irrespective of the number of visits, a
good quality of endodontic treatment must be provided.
References
1. Ashkenaz PJ. One-visit endodontics. Dent Clin North AM
1984;28(4):853-63.
2. Damle SF, Kakade A, Bhavsar JP. Endodontic treatment of
primary molars: A comparison of single and multiple visit
techniques. J Indian Dent Assoc 1995;66(2):18-22.
3. Oliet S. Single-visit endodontics: A clinical study. J Endod
1983;9:147-52.
4. Ingle JI, Bakland LK. Modern endodontic therapy. In: Ingle JI,
editor. Endodontics.Hamilton Ontario, Canada: Elsevier;
2002.p. 15-20.
5. Grossman LI, Oliet S, Del Rio CE. Single visit endodontics. In:
Grossman LI, editor. Endodontic practice. Philadelphia:Lea
& Febiger;1988.p.349-50.
6. Mohammadi Z, Farhad A, Tabrizizadeh M. One visit versus
multiple visit endodontic therapy-A Review. Int Dent J 2006;
56:289-93.
7. Munce R, Teplitsky P. Point of care. J Can Dent Assoc 2005;
71(1):46-51.
8. Figini L, Lodi G, Gorni F, Gagliani M. Single versus multiple
visits for endodontic treatment of permanent teeth: A
Cochrane review. J Endod 2008;34(9):1041-47.
Journal of Health Sciences and Research, Volume 2, Number 1, April - 2011
Review Article
9. Regan JD, Gutmann JL. Preparation of the root canal system.
In: Pittford, editor. Harty’s Endodontics in Clinical Practice,
Edinburgh:Wright;2004.p.90-94.
10. Behrend GD, Cutler CW, Gutmann JL. An in-vitro study of
smear layer removal and microbial leakage along root-canal
fillings. Int Endod J 1996;29:99–107.
11. Bender IB. Factors influencing the radiographic appearance of
bony lesions. J Endod 1997;23(1):5–14.
12. Wahl M J. Myths of single visit endodontics. Gen Dent
1996;44(2):126-29.
13. Glickman G. 21st century endodontics. J Am Dent Assoc
2000;131:39-46.
14. Zehnder M. Root canal irrigants. J Endod 2006;32(5):389-98.
15. Torabinejad M, Ung B, Kettering JD. In-vitro bacterial
penetration of coronally sealed endodontically treated teeth.
J Endod 1990;12:566–69.
16. Orstavik D, Kerekes K, Molven O. Effects of apical reaming
and calcium hydroxide dressing on bacterial infection during
treatment of apical periodontitis. Int Endod J 1991;24(1):117. Trope M, Delano EO, Orstavik D. Endodontic treatment of
teeth with apical periodontitis: Single vs. Multivisit treatment.
J Endod 1999;25(5):345-50.
18. Shabahang S. Chemical debridement. J Am Dent Assoc
2005;136(1):41-52.
19. Spanberg LSW, Haapasalo M. Rationale and efficacy of root
canal medicaments and root filling materials with emphasis
on treatment outcome. Endod Topics 2002;2:35-58.
Journal of Health Sciences and Research, Volume 2, Number 1, April - 2011
28