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 Table of Contents  
ORIGINAL RESEARCH
Year : 2018  |  Volume : 10  |  Issue : 6  |  Page : 303-309

A preliminary assessment of endodontic difficulty encountered at a tertiary health center in Lagos, Nigeria


1 Department of Restorative Dentistry, Lagos State University Teaching Hospital, Ikeja, Lagos, Nigeria
2 Department of Preventive Dentistry, Lagos State University Teaching Hospital, Ikeja, Lagos, Nigeria
3 Department of Restorative Dentistry, Lagos University Teaching Hospital, Surulere, Lagos, Nigeria
4 Department of Oral Medicine/Pathology, Lagos State University Teaching Hospital, Ikeja, Lagos, Nigeria

Date of Web Publication24-Dec-2018

Correspondence Address:
Dr. Afolabi Oyapero
Department of Preventive Dentistry, Lagos State University College of Medicine, Ikeja, Lagos
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jioh.jioh_200_18

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  Abstract 

Aim and Objectives: The complex anatomy of the root canal system, the challenging oral environment, and a host of patient factors can present challenges to achieving the goals of endodontic treatment. There are no clear guidelines on when a general practitioner should refer to an endodontist, and standardized forms for assessing endodontic case difficulty are rarely used in dental practices. The aim of this study was thus to assess the level of endodontic difficulty at the Restorative Dentistry Clinic at the Lagos State University Teaching Hospital, Ikeja. Materials and Methods: The participating dentists assessed the cases presenting in the clinic by reviewing the patient's history, conducting a detailed oral examination, and a radiographic review. The level of endodontic difficulty was assessed using the American Association of Endodontic Case Difficulty Assessment Form and Guidelines. Data were analyzed using the Statistical Package for the Social Sciences for Windows Version 20 (IBM Corp., Armonk, New York, USA), and the Chi-square test was used to determine the level of association between the variables. A 95% confidence interval and a 5% level of significance were adopted. Results: A total of 200 respondents were seen. Majority were females (40; 60%), aged between 21 and 40 years (110; 55%), and had a tertiary level of education (75.5%); most of them had no underlying medical problem (93%), were cooperative and compliant (88%), and had no limitation in mouth opening (95%) and no jaw swelling (87.5%). Most respondents (190; 95%) had signs and symptoms consistent with recognized pulpal and periapical conditions, with minimum radiographic difficulty (192; 96%) and normal crown morphology (89.5%). Canal was visible and not reduced in size in 89% of the study participants. The highest difficulty values were obtained under the diagnostic and treatment criteria, where fifty (25%) teeth had moderate endodontic difficulty, while 11 (5.5%) had high difficulty. Conclusion: Majority of the root canal treatment (RCT) cases seen were of minimal difficulty and could be treated by general practitioners or resident doctors. About 5.5% of the study participants, however, required specialist care. Case selection is the process of discriminating cases according to their prognosis. Clinicians must thus be able to assess and make a practical decision about the complexity of RCT and decide whether it is within their capabilities.

Keywords: Complexity, endodontic difficulty, root canal treatment


How to cite this article:
Enone LL, Oyapero A, Awotile AO, Ijarogbe O, Akinleye AI, Dahunsi M. A preliminary assessment of endodontic difficulty encountered at a tertiary health center in Lagos, Nigeria. J Int Oral Health 2018;10:303-9

How to cite this URL:
Enone LL, Oyapero A, Awotile AO, Ijarogbe O, Akinleye AI, Dahunsi M. A preliminary assessment of endodontic difficulty encountered at a tertiary health center in Lagos, Nigeria. J Int Oral Health [serial online] 2018 [cited 2019 Jun 24];10:303-9. Available from: http://www.jioh.org/text.asp?2018/10/6/303/248434


  Introduction Top


Clinical decision-making is a multifactorial procedure that involves the integration of evidence from clinical practice, pertinent research, and patient predilections and goals for expected outcomes.[1] Root canal treatment (RCT) or endodontic therapy involves procedures that are designed to maintain the health of all or part of the pulp, and it is one of the basic procedures performed in dentistry, directed at prevention or elimination of apical periodontitis (AP).[2] AP is an inflammatory periradicular lesion of endodontic origin sequel to dental caries, trauma, and operative procedures.[3] The morphologically complicated nature of the root canal system, the challenging oral environment, and a host of patient factors can however present challenges to achieving the goals of endodontic treatment.[4]

Another challenging reality of RCT is the impact of nonendodontic factors on endodontic outcomes.[4] Factors including but not limited to the type and severity of disease, the type and location of the affected root canal,[5] the instrumentation and technology used in treating and assessing the status of the affected root canal,[6] and the expertise of the treating clinician,[7] all potentially impact treatment success or failure. Treatment outcome can vary in single- and multi-rooted teeth, anterior and posterior teeth, and the anatomic complexity or difficulty of access to the canal. The success of endodontically treated teeth can furthermore be affected by prosthetic considerations, the placement and quality of the subsequent restoration, and periodontal factors. A favorable prognosis in RCT correspondingly depends on the clinician's technical experience and skills, in interpreting radiographic findings and establishing a diagnosis.[8] Experienced and skillful operators are less likely to compromise the outcome of treatment through procedural errors.[8]

The acceptability of endodontic treatment is on the increase among Nigerian patients, with more people desiring to keep their teeth,[9] and recent estimates also place the number of root canal procedures performed within the United States at 15.1 million annually. Of these, general dentists complete 72% of cases, while endodontists are responsible for the remaining 28%.[10] Endodontists have been found to perform more molar root canal therapy, conventional retreatment, and surgical endodontic procedures than general dentists who provide endodontic treatments.[11] Success rates were notably higher when an endodontic specialist performed the procedure versus a general dentist. In a survey of the survivability of teeth that underwent an endodontic procedure, endodontists experienced statistically significantly greater treatment success (98.1%) than general dentists (89.7%).[12]

In order to improve the success rate of RCT in general dental practice, the referral of difficult cases to specialists in endodontics should be facilitated. In order to refer patients with complex endodontic problems, there must be an adequate number of endodontists to handle the demand for specialist care, and general practitioners must be able to assess the difficulty of the endodontic procedure. There are no clear universal guidelines on when a general practitioner should refer to an endodontist, and standardized forms for assessing endodontic case difficulty are rarely used in dental practices.[13] The aim of this study was thus to assess the level of endodontic difficulty at the Restorative Dentistry Clinic at the Lagos State University Teaching Hospital (LASUTH), Ikeja, using the American Association of Endodontic (AAE) Case Difficulty Assessment Form and Guidelines.[14]


  Materials and Methods Top


This cross-sectional, interviewer-administered, questionnaire-based study was conducted among patients presenting for endodontic treatment at the LASUTH, Ikeja. LASUTH is a tertiary health facility situated in the capital of Lagos state. It is a multispecialist hospital with about 800 beds.

Sampling method

A simple random sampling technique using the balloting method was used to determine the study participants using the appointment register of patients in each clinic day as the sampling frame. The selected participants were screened for eligibility by set inclusion and exclusion criteria and those that met these criteria and who gave their informed consent were included in the study.

Sample size

The sample size for the study was determined using a formula for cross-sectional studies and using the prevalence of 71.88% good knowledge of endodontic treatment protocol from a reference study,[15] a sample size of 180 was determined; this was increased to 200 to make provision for incomplete responses and to make provision for study design errors.

Selection criteria

The participants were selected based on the following criteria:

Inclusion criteria

  • Participants must be aged 18 years and above
  • Participants with vital teeth, with acute irreversible pulpitis, AP, or endodontic retreatment.


Exclusion criteria

  • Participants who declined to participate
  • Immunocompromised participants.


Study population

The study population consisted of 200 patients with 185 teeth that had initial endodontic treatment and 15 retreatment cases by the senior registrars in the Conservative Dentistry Unit under the direct supervision of qualified endodontists. Al1 the pre- and intra-operative information pertaining to each treated tooth, including clinical and radiographic data, was recorded. Al1 radiographs were taken with the paralleling technique using a Kerr X-ray film holder® West Collins Orange, CA with a constant exposure, and films were developed manually under standard conditions. The films were observed under standard settings using a view box and magnification. Prior to the radiographic evaluation, the principal and co-principal investigators were calibrated with a set of thirty randomly selected periapical radiographs while intra- and inter-examiner reliability was assessed using Cohen's kappa statistic.

Data collection

The participating dentists (ELL and OA) assessed the cases presenting in the clinic by reviewing the patient's history, conducting a detailed oral examination, and a radiographic review. The level of endodontic difficulty was assessed using the AAE Endodontic Case Difficulty Assessment Form and Guidelines. A structured interviewer-administered questionnaire was used for data collection. They then administered a close-ended questionnaire which was subdivided into two main parts (sociodemographic information; AAE Endodontic Difficulty Questionnaire) on the respondents. The first part sought for information regarding age, gender, working status, and educational qualification of the respondents. The 17-item AAE Endodontic Difficulty Questionnaire obtained information on (a) patient considerations in endodontic treatment such as medical history, anesthesia problems, patient disposition and compliance, gag reflex, and emergency conditions; (b) diagnostic and treatment considerations: diagnosis, radiographic difficulties, tooth position in the arch, root canal morphology, radiographic appearance of canals and resorption; and (c) additional considerations such as trauma history, endodontic treatment history, and periodontal endodontic condition.

Ethical considerations

The procedure for this study was presented to the Health Research and Ethics Committee, LASUTH, and written approval was acquired (LREC. 06/10/1077). Participation was voluntary for all participants, and they were informed that they were free to decline to enlist and to withdraw from the study. Written informed consent was obtained from all the participants.

Data analysis

Data were analyzed using the Statistical Package for the Social Sciences for Windows Version 20 (IBM Corp., Armonk, New York, USA). Frequency distribution tables were generated for all variables, and measures of central tendency and dispersion were computed for numerical variables. Since the data were normally distributed as assessed by the Shapiro–Wilk test, descriptive statistics including means, standard deviations, and percentages were used to summarize the demographic variables. The Chi-square test was used to determine the level of association between the variables. A 95% confidence interval and a 5% level of significance were adopted.


  Results Top


A total of 200 respondents were seen. Majority were females (40; 60%), aged between 21 and 40 years (110; 55%), were working full time (112; 56%), and had a tertiary level of education (151; 75.5%) [Table 1].
Table 1: Sociodemographic characteristics of respondents

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Most of the study participants had no underlying medical problem (186; 93%), had no history of anesthesia problem (198; 99%), were cooperative and compliant (176; 88%), and had no limitation in mouth opening (190; 95%). Only three (1.5%) respondents had gag reflex, while 25 (12.5%) had jaw swelling/dentoalveolar abscess [Table 2].
Table 2: Patient consideration factors

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Most of the respondents (190; 95%) had signs and symptoms consistent with recognized pulpal and periapical conditions, with minimal radiographic difficulty (192; 96%). Root-filled teeth were mainly anterior/premolar (132; 66%), while rubber dam was only used in 54 (27%) cases. Most of the teeth had normal crown morphology (179; 89.5%); the canal was visible and not reduced in size in 179 (89%) teeth; 183 (91.5%) teeth had no evidence of root resorption [Table 3].
Table 3: Diagnostic and treatment consideration factors

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Twenty-one (10.5%) of the treated teeth had complicated crown fracture, while 15 (8%) had a history of previous endodontic treatment. Twenty-three (11.5%) respondents however had concurrent moderate periodontal disease [Table 4].
Table 4: Addition considerations for case difficulty assessment

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Using the AAE criteria, only two (1%) patients had a high difficulty under the patients' consideration criteria. Under the diagnostic and treatment considerations, 11 (5.5%) patients had a high level of difficulty, while two (1%) patients had it under the additional considerations. The highest values were obtained under the diagnostic and treatment criteria where fifty (25%) teeth had moderate endodontic difficulty, while 11 (5.5%) had high difficulty [Table 5].
Table 5: Level of endodontic difficulty based on American Association of Endodontic criteria

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Respondents aged ≥61 years had statistically significantly higher number of cases with moderate and high levels of endodontic difficulty [Table 6].
Table 6: Association between sociodemographic variables and level of endodontic difficulty

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  Discussion Top


The present clinical study was designed to assess the level of endodontic difficulty among patients undergoing initial treatment and retreatment at the Restorative Dentistry Clinic at the LASUTH, Ikeja, using the AAE Case Difficulty Assessment Form and Guidelines. When the pulp is irreversibly damaged, the goal is to prevent infection and periapical disease. Making a treatment decision is a demanding task for a dental professional, resulting in considerable variation in treatment practices. Case selection is the process of discriminating cases according to their prognosis.

The outcome of endodontic treatment was determined using the Case Difficulty Assessment Form and Guidelines which classify the procedure as having minimal difficulty when the preoperative condition indicates routine complexity and a predictable treatment outcome can be attainable by a competent practitioner with limited experience and moderate difficulty when the preoperative condition is complicated, exhibiting one or more patient or treatment factors listed in the moderate difficulty category and achieving a predictable treatment outcome will be challenging for a competent, experienced practitioner. High difficulty indicates preoperative conditions that are exceptionally complicated, exhibiting several factors listed in the moderate difficulty category or at least one in the high difficulty category. Level 1 complexity treatment can be adequately treated within the skill range of the general dental practitioner. Level 3 complexity treatment must be done by an endodontic specialist, while Level 2 complexity represents treatments that lie in between and require the skill of qualified and experienced practitioners.

The key findings of this research were that majority of the RCT cases seen were of minimal difficulty and could be treated by general practitioners or resident doctors. Under the diagnostic and treatment considerations, 11 (5.5%) patients had a high level of difficulty, while two (1%) patients had it under the additional considerations. The highest values were obtained under the diagnostic and treatment criteria where fifty (25%) teeth had moderate endodontic difficulty, while 11 (5.5%) had high difficulty and required specialist care. A limitation of our study was that even though a probability random sampling technique was utilized in the sample selection, the fact that only a public tertiary health facility was utilized makes it possible that differences may exist between the study sample and the population from which they were drawn; thus some caution is required in the generalization of the results. Another limitation of our study was its cross-sectional and descriptive design; hence, follow-up studies on a larger scale could require a randomized controlled trial design.

There were very few patient considerations that increased the level of difficulty encountered in treating the patients. Only a small number of patients had one or more medical problems (7%), while 11.5% were anxious but cooperative. However, 12.5% had moderate pain or swelling, presenting as endodontic emergency. Endodontic pain may differ in severity and source depending on its origin (pulpal or periradicular). Endodontic emergencies account for one-third of dental emergency cases and its management poses one of the most challenging aspects of clinical dentistry.[16] Managing the emergency condition when there is pulpal necrosis with fluctuant swelling may involve drainage through the canal, complete canal instrumentation, incisions and drainage, placement of intracanal medicament, and prescribing analgesics according to the standard protocols.[17]

The diagnostic and treatment considerations however constituted the greater part of considerations in categorizing patients as having moderate or high endodontic difficulty. Eight patients had moderate difficulty with obtaining and interpreting their radiographs due to anatomical challenges such as high floor of the mouth, narrow or low palatal vault, and the presence of tori mandibular or maxillary tori or exostosis. Radiographic examination is an essential component of endodontic management, and it serves as the foundation for diagnosis, treatment planning, intraoperative monitoring, and outcome assessment.

Anterior teeth and premolars made up 66% of the teeth treated among our respondents. Similarly, Ingle et al.[18] in their study found that maxillary incisors accounted for 45.88% of the 1229 cases, with the mandibular first molar being the third most frequently treated tooth, constituting 10.33% of all cases. This result was however at variance with the study by Boykin et al.[19] who observed that mandibular and maxillary molars were the most frequently treated teeth. With regard to tooth position in the arch, fifty (25%) teeth in our study were either 1st molar or had moderate inclination (10°–30°) or moderate rotation (10°–30°) and thus are of moderate endodontic difficulty, while 11 (5.5%) teeth were either 2nd or 3rd molar or had extreme inclination (>30°) or extreme rotation (>30°) and are of high endodontic difficulty.

The effect of tooth position and type on endodontic treatment outcome has been investigated by some authors. Some researchers found no difference in treatment outcome between the different tooth types,[20],[21] while Cheung and Chan[22] found that maxillary and mandibular molars and maxillary premolars had a poorer prognosis after root canal therapy than maxillary and mandibular anteriors and premolars. Although there is no consensus on the effect of the tooth type, it seems logical that posterior teeth, due to their higher number of canals, have a theoretically higher chance of failure, which is the summation of the possible chances of failure for each canal individually. This is plausible because the anatomy of the multirooted and varying pulp canal configuration teeth presents a greater challenge for elimination of root canal infection.[23] Respondents aged ≥61 years had statistically significantly higher number of cases with moderate and high levels of endodontic difficulty. This suggests that it is mandatory to adequately assess elderly patients that require endodontic treatment.

Fifteen patients (7.5%) had previous endodontic treatment, with 14 having previous access without complications, while one had previous access with complications such as perforation, nonnegotiated canal, and ledge or separated instrument. The former will require the skills of experienced practitioners, while only an endodontist should treat the latter. Primary RCT has a success rate of 85% according to a systematic review with meta-analysis of 63 studies based on at least 6-month review.[24] Among endodontic specialists, however, the chances of achieving a successful result in initial nonsurgical endodontic treatment are generally considered good with estimates as high as 97%.[25] The success rate of secondary RCT was 77% in another systematic review with 17 studies, with at least 6-month review.[26] This discrepancy in success rates may reflect a difference in the quality of endodontic treatment performed, despite improvements in instruments and materials, as well as advances in the understanding of the disease process. Thus, cases of retreatment should be adequately assessed and referred to a specialist.

The key findings in our study were in agreement with the outcomes observed by Hull et al.,[11] where general dental practitioners provided 75% of all nonsurgical endodontic treatments. It is a positive finding in this study that 70% of the endodontic treatments in our study population had minimal difficulty. This shows that majority of the patients presenting in our health facility can be appropriately attended to by a general dental practitioner or dentists including interns, dental officers, and junior residents with adequate training. This observation is heartening because specialist dental services are a scarce resource which are often oversubscribed.[27] Twenty-five percentage of the respondents will however require the expertise of skilled and appropriately qualified dental personnel such as senior registrars. The rest (5%) will need to be attended to by a specialist (endodontist). Success rates for endodontic treatment have not dramatically changed over the last five decades, despite significant technological advances[28] and operator training, which is associated with improved success.[29]

The immediate implication of our research is that the dentist has an ethical obligation to render optimal treatment to patients and to provide information about the available optimal treatment alternatives. The potential for medicolegal consequences should be a strong driver of referral because RCT accounted for approximately 18% of the total number of dentolegal claims in a 5-year sample of completed cases between 1996 and 2001.[30] Thus, there are substantial medicolegal implications for dentists undertaking complex treatment that is beyond their competence. Consequently, an envisaged policy direction is the mandatory use of the AAE Endodontic Difficulty Questionnaire for all patients that require endodontic treatment at their initial visit. A large-scale study involving more tertiary, secondary, and private dental facilities is the future direction of this research. This will involve randomized controlled trials with long-term follow-up of patients seen by the different cadre of dental professionals with a view of correlating the initial assessment of endodontic difficulty with long-term prognosis.


  Conclusion Top


Majority of the RCT cases seen were of minimal difficulty and could be treated by general practitioners or resident doctors. Under the diagnostic and treatment considerations, 11 (5.5%) patients had a high level of difficulty, while two (1%) patients had it under the additional considerations. The highest values were obtained under the diagnostic and treatment criteria, where fifty (25%) teeth had moderate endodontic difficulty, while 11 (5.5%) had high difficulty and required specialist care. Case selection is the process of discriminating cases according to their prognosis. Clinicians must thus be able to assess and make a practical decision about the complexity of RCT and decide whether it is within their capabilities.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]



 

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