Abstract
Background
Irreversible pulpitis is a painful and debilitating condition. Root canal treatment (RCT) provides prompt relief and salvages the affected tooth/teeth. It has classically been performed as a multivisit procedure. A relatively newer approach constitutes performing all the steps in one single visit. This study was designed to explore if single-visit RCT could be confidently used as an effective and preferred treatment modality for irreversible pulpitis in the Indian Armed forces.
Methods
The study compared the incidence of postoperative pain, tenderness on percussion (TOP), flare-ups, and the analgesic drug use in 60 cases of acute irreversible pulpitis who were treated by either single or multiple visit root canal therapy. Each treatment group included 30 patients who were evaluated preoperatively and postoperatively at 24 h, one week and one month.
Results
The study found statistically higher incidence of postoperative pain (mild variant) and TOP in single visit therapy, 24 h after the obturation while the difference was insignificant at one week and one month after therapy. Analgesic use was significantly higher after the single visit therapy in the first 24 h. No flare-ups were recorded in either group. Significant pain and tenderness was observed after chemo-mechanical preparation (appointment 2) in multivisit regimen.
Conclusion
Single visit therapy is a safe, practical, and effective approach. The treatment results are similar to the multivisit regimen. It should therefore be considered for wider adoption and application.
Keywords: Single visit endodontic treatment, Irreversible pulpitis, Root canal treatment (RCT)
Introduction
Acute inflammation of the dental pulp tissue (Pulpitis) secondary to microbial invasion is one of the most common reasons to seek emergency dental treatment. The condition can be extremely painful, debilitating and adversely affects the quality of life of those affected. Prompt diagnosis and effective endodontic intervention in the form of root canal treatment (RCT) usually provides the necessary relief and salvages the affected tooth/teeth. The RCT has classically been performed as a multivisit procedure with steps such as access opening, biomechanical preparation, chemical debridement and obturation performed for more than three or more appointments. The regimen is widely accepted, has produced consistent results, and remains a technique of choice for most clinicians.1,2 A relatively newer approach though includes performing all the steps in one single visit.
Treatment in one visit has some definite advantages. The total chair side time is markedly reduced. The operator need not be concerned about the problems of inter appointment leakage, loss of temporary seal or any of the accidents that could occur between the visits. The patient does not have to undergo additional local anesthetic injections, repeated rubber dam placements, and make multiple visits. Nonetheless, some shortcomings also exist. The single visit procedure eliminates some of the controls available in multiple visit treatment such as culturing to check the effectiveness of chemo-mechanical debridement and revaluation of tissue responses after treatment procedures. Owing to its inherent finality, it is difficult to revise the treatment course and institute alternate therapies if needed, especially in the event of postoperative pain or a flare-up. Therefore, a degree of apprehension surrounds the single visit RCT. This might dissuade a clinician from performing an otherwise indicated and potentially advantageous procedure.
The study included Indian armed forces personnel and their families. It was designed to find out if single-visit RCT could be confidently used as an effective and preferred treatment modality in cases of irreversible pulpitis. The aim was to evaluate and compare the incidence of postoperative pain, tenderness, flare-ups, and the use of analgesic drugs in patients treated by single and multiple visit RCT.
Materials and methods
Study design
The study included newly diagnosed cases of acute irreversible pulpitis in cariously exposed mandibular first molars in patients of ages 18–40 yrs, who were treated with RCT. The patients were divided into two treatment groups for the study.
Group A: 30 cases treated in a single visit.
Group B: 30 cases treated in multiple visits.
Group allocation and randomization was carried out by a designated personnel using manual lottery method. Thirty allocation slips in unmarked envelopes were drafted for each group and combined to create the lottery pool. For every new participating subject, an allocation slip was awarded by lottery and the group was assigned. Blinding was done at the level of data gathering and data analysis.
Patients with systemic diseases, cognitive dysfunction, immune-compromised patients, retreatment cases, and pregnant females were excluded. Teeth with compromised periodontal support, fractures, draining sinuses, tenderness on percussion (TOP), unfavorable morphology and radiographic evidence of pulpal calcifications or distorted root anatomy were also excluded.
The study was cleared by the Institutional Review Board, Military Hospital, Ahmednagar vide letter no. 15965/4602/2014–2015/DGAFMS/DG-3B. Written informed consent was obtained from all participating subjects.
Endodontic techniques
Detailed medical and dental history was elucidated followed by thorough clinical examination. Preoperative (T0) level of pain was noted. Rubber dam was used in all the cases. All the procedures were performed under local anesthesia (2% lignocaine with 1:80,000 Adrenaline).
In group B, the treatment was imparted for more than three visits (Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5).
Fig. 1.
Armamentarium.
Fig. 2.
Carious left mandibular first molar diagnosed with irreversible pulpitis.
Fig. 3.
Isolation with rubber dam followed by access opening and coronal flaring.
Fig. 4.
Apex locator for working length determination.
Fig. 5.
Preoperative, working length, and postoperative radiographs.
First visit: Access opening and coronal flaring, followed by closed dressing. An aqueous solution of calcium hydroxide was used as interappointment, intra-coronal medicament.
Second visit: Working length determination and chemo-mechanical preparation, followed again by closed dressing. Working length determination was carried out with electronic apex locator (Root ZX, J Morita USA Inc.) up to apical constriction (minor apical diameter) and reconfirmed radio graphically. Rotary Nickel Titanium files (Protaper, Dentsply Sirona Inc, North Carolina, USA), on X Smart endomotor (Dentsply) were used in Crown-down technique for chemo-mechanical preparation. Final file size achieved was usually F3 (30) and F4 (40) for mesial and distal canals, respectively. Sodium hypochlorite solution of 5.25% (Novo, Zahnsply) and EDTA gel (Glyde, Dentsply) were used as intra-canal irrigant and lubricating agent, respectively.
Third visit: Obturation and restoration with light cure composite. Obturation was carried out with Gutta percha cones (Protaper, Dentsply) and resin-based root canal sealer (AH-26, Dentsply) using lateral condensation technique. Postoperative radiographs were taken to evaluate the quality of obturation.
The patients were recalled a day after every visit to evaluate interappointment pain, flare-up or any other associated complication and use of medication (Ibuprofen 400 mg, as on required basis). After the obturation, the same parameters were reassessed on day 1(T1), day 7 (T2), and day 30 (T3).
In group A patients, the same procedures were completed in a single appointment. The patients were recalled the very next day (T1) to evaluate postoperative pain, flare-up, or any other associated complication and use of medication (Ibuprofen 400 mg, as on required basis). The variables were reassessed on 7th day (T2) and 30th day (T3) postobturation. Fig. 1 = for consort diagram.
The subjects were asked to ratify their pain on a visual analog scale of 0–10. Comparative pain scale (Table 1) was used to help patients quantify their pain. A reading of ‘0’, ‘1 to 3’, ‘4 to 6’ and ‘7 to 10’ was read as ‘no pain’, ‘mild pain’, ‘moderate pain’ and ‘severe pain’, respectively. Sustained effort was made at all stages to eliminate all probable and anticipated causes of pain so that unbiased and comparable outcomes were achieved.
Table 1.
Comparative pain scale for ready reference.
| Amount of pain | Reading | Signs |
|---|---|---|
| No pain | 0 | Feeling perfectly normal |
| Mild pain | 1 | Very light barely noticeable pain, discomforting but tolerable. Does not interfere with most daily activities. Able to adapt psychologically or with medication |
| 2 | ||
| 3 | ||
| Moderate pain | 4 | Strong pain is noticeable at all times, distressing, intolerable requiring definitive medication. Patient is unable to completely adapt to pain and partially dominates senses causing to think somewhat unclearly but patient remains independent. |
| 5 | ||
| 6 | ||
| Severe | 7 | Pain is very intense, excruciating, unbearable completely dominating senses, cannot think clearly, patient is effectively disabled and cannot live independently. Painkillers are not helpful and requires an emergency visit to the hospital |
| 8 | ||
| 9 | ||
| 10 |
Both the groups were monitored for the occurrence of flare-ups. Severe uncontrollable amount of inter appointment and postoperative pain, not relieved by medication, requiring an unscheduled visit to the dental office for active treatment was classified as a flare-up.
Chi square test was used for statistical analysis. P value less than .05 was taken to be significant.
Results
A total of 60 patients (24 males, 36 females) with a mean age of 30.6 yrs completed the study..
Evaluation of postoperative pain [Table-2]
Table 2.
Incidence of postoperative pain.
| Single visit group A | Multiple visit group B | |||||||
|---|---|---|---|---|---|---|---|---|
| Pain | T0 | T1 | T2 | T3 | T0 | T1 | T2 | T3 |
| None | 26.7% | 20% | 73.3% | 100% | 16.7% | 66.7% | 86.7% | 100% |
| Mild | 23.3% | 66.7% | 20% | NIL | 26.7% | 30% | 13.3% | NIL |
| Moderate | 13.3% | 13.3% | 6.7% | NIL | 16.6% | 3.3% | NIL | NIL |
| Severe | 36.7% | NIL | NIL | NIL | 40% | NIL | NIL | NIL |
Postoperative pain at T1
Statistically significant (P = .003) number of patients in Group A reported mild pain (66.7%) as compared with those in Group B (30%). Statistically significant numbers of patients were painless in Group B (66.7%) as compared with Group A (20%). Though statistically insignificant, incidence of moderate pain in Group A (13.3%) was greater than in Group B (3.3%). There was no incidence of severe pain in either group.
Postoperative pain at T2
Significant increase was seen in the number of Group A patients who became painless (20%–73.3%) along with a corresponding significant drop in the number of patients with mild pain. Group B patients also demonstrated improvement in pain though not to a significant level.
Postoperative pain at T3
Patients in both the groups had no pain after one month of obturation..
Evaluation of TOP [Table 3]
Table 3.
Incidence of postoperative tenderness on percussion (TOP).
| Group A |
Group B |
|||
|---|---|---|---|---|
| Present | Absent | Present | Absent | |
| Day 1 | 36.7% | 63.3% | 16.7% | 83.3% |
| Day 7 | 23.3% | 76.7% | 16.7% | 83.3% |
| Day 30 | Nil | 100% | Nil | 100% |
Postoperative TOP at T1
Significantly greater number of patients had TOP in Group A as compared with Group B (P value = .04).
Postoperative TOP at T2
There was an improvement in TOP in Group A, although it was not significant. No change was seen in Group B.
Postoperative TOP at T3
All the patients in both the groups did not have any TOP after a month..
Postoperative analgesic use (standard dose of tab ibuprofen 400 mg) [Table 4]
Table 4.
Postoperative medication use (standard dose of Tab ibuprofen 400 mg).
| Group A |
Group B |
|||
|---|---|---|---|---|
| Taken | Not taken | Taken | Not taken | |
| Day 1 | 73.3% | 26.7% | 30% | 70% |
| Day 7 | 16.7% | 83.3% | 6.7% | 93.3% |
| Day 30 | Nil | 100% | Nil | 100% |
At T1, significantly higher number [P value = .04] of Group A patients (73.3%) took medication to alleviate pain as compared with Group B (30%). At T2, most patients (83.3% in Group A and 93.3% in Group B) did not take any medication. At T3, no medication use was observed in either group.
Postoperative swelling and flare-ups
No postoperative swelling or flare-ups were observed in either group.
Assessment of interappointment pain, TOP and analgesic use in group B
Significant increase (P value = .05) was seen in the number of patients with ‘no pain’ after the first appointment [Table 5]. After the second appointment though, there was significant increase in patients with mild pain. The pain decreased again after the third appointment. Significant increase in the TOP was seen after the second appointment [Table 6]. The TOP improved after the third appointment, although the change was not statistically significant. Significant increase [Table 7] in the number of patients taking analgesics was seen after appointment no 2 (when chemo-mechanical preparation was carried out).
Table 5.
Assessment of intra-appointment pain in group B.
| No pain | Mild pain | Moderate pain | Severe pain | |
|---|---|---|---|---|
| Preoperative pain | 16.7% | 26.6% | 16.7% | 40% |
| Pain after appt no. 1 | 66.7% | 30% | 3.3% | NIL |
| Pain after appt no. 2 | 10% | 76.6% | 10% | 3.4% |
| Pain after appt no. 3 (or T1) | 66.7% | 30% | 3.3% | NIL |
| T2 | 86.7% | 13.3% | NIL | NIL |
| T3 | 100% | NIL | NIL | NIL |
Table 6.
Assessment of intra-appointment tenderness on percussion (TOP) in group B.
| Present | Absent | |
|---|---|---|
| Preoperative | Nil | 100% |
| After aptt no. 1 | 10% | 90% |
| After aptt no. 2 | 23.4% | 76.6% |
| After aptt no. 3 or T1 | 16.7% | 83.3% |
| T2 | 16.7% | 83.3% |
| T3 | NIL | 100% |
Table 7.
Assessment of intra-appointment medication taken in group B (standard dose of Tab ibuprofen 400 mg).
| Taken | Not taken | |
|---|---|---|
| Preoperative | Nil | 100% |
| After aptt no. 1 | 66.7% | 33.3% |
| After aptt no. 2 | 80% | 20% |
| After aptt no. 3 (or T1) | 30% | 70% |
| T2 | 6.7% | 93.3% |
| T | Nil | 100% |
Discussion
Swift diagnosis and timely intervention are cornerstones in the effective management of painful conditions. This acquires far greater significance in Defense forces where treatment time and recovery is directly associated with force deployability and combat readiness. Multiple visits for a treatment procedure, which could otherwise be performed in a single visit, results in higher turnaround time and subpar utilization of human resources. The soldiers and their families, especially those posted in relatively remote areas with limited access to more advanced treatment facilities, have to make several visits to the nearest higher centre which disrupts their normal routine and adversely affects their morale.
RCT is a commonly performed procedure which provides pain relief in irreversible pulpitis, without having to extract the tooth. The procedure, when performed following the established principles, has a good success rate and low complications.2 However, the traditional technique involves multiple steps which are undertaken over three or more appointments. Single visit RCT aims to complete all the steps in one single visit and presents some obvious advantages.
Despite being in existence for quite some time and comprehensively described in literature, the technique has still not found substantial acceptance amongst the dental operators. A common reason is the apprehension associated with the postoperative sequelae such as pain, tenderness, and flare-ups. Such complications, when they occur in single visit therapy, are more challenging to manage as the absolute nature of the treatment leaves little scope for re-evaluation and correction. The study, therefore, sought to explore if such apprehensions were well founded.
The common factors contributing to unwarranted postoperative sequelae include inadequate instrumentation, extrusion of irrigant solution, intracanal dressings, traumatic occlusion, missed canal, preoperative pain, periapical pathosis, and extrusion of apical debris. According to Seltzer, apical extrusion of infected debris during chemo-mechanical instrumentation causes release of inflammatory mediators and is the main etiological factor for periapical inflammation and postoperative pain. Seltzer3 further noted a relationship between the level of root canal obturation and the incidence of postoperative pain and reported postoperative pain in 14%, 53%, and 60% of patients with under filling, flush filling and over filling, respectively. Kane et al. 4 observed that apical length of canal filling was the only significant factor affecting postoperative pain. Gesi et al. 5 concluded that over instrumentation and overfilling was associated with an increase in postoperative pain.
The present study evaluated and compared the occurrence of postoperative pain, tenderness, swelling, and the need for analgesic medication after obturation in single and multiple visit endodontic therapy of cariously exposed vital mandibular first molars. The same variables were also compared across the multiple visits undertaken in the group B. To the best of our knowledge, very few studies have performed such comparative evaluation within the multivisit group.
The study found that a day after the obturation, the single visit group was associated with statistically significant postoperative pain (mild variant). Both the groups did not report any significant pain of moderate or severe nature. A week after the obturation, pain scores improved in both the groups and there was no significant difference in pain (mild, moderate and severe) between the two groups. By the end of one month, both the groups were absolutely painless. These findings are in agreement with similar studies which have found no significant difference in the incidence of postoperative pain in the two groups.6, 7, 8, 9, 10, 11 Most of these studies report only a mild form of pain in the first 24–48 h, which gradually disappeared over the week.
The single visit group showed significantly higher incidence of TOP as compared with the multivisit group. After a week though, no significant TOP remained in either group and the difference was insignificant. By the month end, TOP was completely resolved in both groups. This is almost similar to the pattern seen in evaluation of pain because same factors are associated with their causation. Frequency of analgesic use followed the findings of pain and TOP. Significantly higher analgesic use was seen in single visit group a day after the obturation. The analgesic use gradually dropped over the week and was down to zero by the month end.
Most studies compare the pain variables after completion of the procedure. That is, both single and multivisit patients are evaluated after completion of therapy. This design does not take into account the pain and tenderness multivisit patients might experience between the appointments. A novel addition to the present study was the evaluation of interappointment pain and tenderness to percussion in group B. It indicated significant pain and TOP after appointment no.2, which was comparable with the pain and TOP in Group A patients, one day after the obturation. Thus, when compared to single visit patients, multi visit patients may experience lower pain and TOP just after the obturation. But it is offset by the occurrence of significantly higher inter appointment pain in during multivisit therapy.
Another important parameter the study evaluated was the occurrence of flare-ups. Flare-ups are most commonly caused when microbial toxins get extruded beyond apical foramen causing acute inflammatory response. This usually follows either over instrumentation or over obturation. Its prevalence has been variably noted to range between 3 and 58 percent.12 Eleazer et al.13 recorded greater flare-ups in cases treated in multiple visits (8%) as compared with those treated in a single visit (3%), whereas Akbar et al.14 reported equal incidence of flare-ups (8–10%) in single and multivisit groups while treating asymptomatic molar teeth with periapical radiolucency. Landers15 too in his study reported no difference in flare-ups between single visit and multiple visit RCT.
In the present study flare-ups were not observed in either group. This was probably made possible by optimum consideration to case selection, good sterilization, isolation, suitable materials and careful technique, the primary goal being minimizing trauma and infection of the periapical region. Only vital teeth with irreversible pulpitis were included, which limited the amount of microorganisms in the root canal system and their chances of being pushed beyond the apex and causing an inflammatory response. Sim16 has reported significantly higher incidence of flare-ups in necrotic than in vital teeth.Trope17 also concluded that teeth without signs of apical periodontitis did not have any flare-ups. However, Imura et al.18 reported no corelation between postobturation flare-ups and the status of the pulp.
Success of endodontic technique, whether performed in single or multiple visits, is based upon accurate diagnosis, proper case selection and operator's skill. These procedures are based upon known biological principles incorporated into the technique triad, that is, chemo-mechanical preparation of the canal system, debridement and disinfection and complete obturation of the prepared canals. Each of these objectives must be achieved to ensure a successful result. Askenaz19 concluded that endodontic competency of the practicing dentist becomes the overriding factor in determining the outcome of any particular case. A careful case selection and adherence to the basic principles of endodontic therapy will reduce the incidence of postobturation pain and flare-ups and thus enhance a successful outcome.20
Summary
The present study found statistically higher incidence of postoperative pain, 24 h after the obturation, in single visit therapy. The pain was essentially of mild variety. The pain scores improved significantly within a week. After a month, all the subjects in both the groups were painless. No severe pain was noted in either group. Single visit therapy was associated with significantly higher incidence of TOP but it improved drastically over the week and completely resolved at the end of the month. The pain and tenderness experienced by patients undergoing single visit therapy, 24 h after obturation, was similar to that experienced by patients undergoing multi visit therapy, 24 h after the second appointment (when chemo-mechanical preparation was done). Medication use was significantly high in the first 24 h of single visit therapy and abated gradually in a week. No flare-ups were recorded in either group of patients. Overall, single visit treatment regimen, when implemented judiciously adhering to the basic principles of endodontic therapy, produced results similar to those of multivisit regimen.
Conclusion
When supported by accurate diagnosis, proper case selection, sound treatment principles and careful adherence to technique, postoperative sequelae in single visit did not differ significantly from multivisit therapy. The single visit therapy should be adopted as a preferred endodontic treatment modality in the armed forces at a larger scale. Its benefits are especially relevant to the field areas, where owing to exigencies of service, it is difficult for the patient to visit dental centers multiple times for the RCT. Endodontics in the Armed Forces is in a nascent stage and there are only a handful of endodontists to cater to the expectations of a vast clientele. The required armamentarium already exists in the Armed Forces Medical Stores. However, wider promotion and greater penetration of this treatment modality amongst dental officers through periodic workshops/CDE programs in the field of single visit rotary endodontics is required. The technique, if universally adopted, holds the promise of providing faster and effective oral healthcare to soldiers and their families, posted in different areas, urban or remote alike. This would go a long way in ensuring high troop morale, optimal use of health infrastructure and effective human resource management.
Disclosure of competing interest
The authors have none to declare.
Acknowledgements
a) Dr Shamaz Mohammed MDS, Associate Professor and Head, Department of Public Health Dentistry, Sri Shankara Dental College, Vennecode, Varkala, Kerala for statistically analysing the reported data.
b) This article is based on Armed Forces Medical Research Committee Project No. 4602/2014 granted by the office of the Directorate General Armed Forces Medical Services and Defence Research Development Organization, Government of India.
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