Comparison of Knowledge Regarding Endodontic Materials and Techniques Among Dentists Employed At Dental Institutions And Private Practices in Karachi, Pakistan

Farhan Raza Khan1                            BDS, MSc, MCPS, FCPS

Sadia Mahmud2                                   MSc, MS, PhD

Munawar Rahman3                            BDS, MCPS, DDS

INTRODUCTION

Endodontics is a branch of dentistry that is concerned with the diagnosis and treatment of dental pulp and associated periapical diseases^[1]. It is considered as one of the most skill intensive discipline of dentistry. In other words, the psychomotor skill of the clinician has the most bearing on the success and failure of an endodontic case^[2]. Globally, a wide majority of the root canal treatment are still undertaken by general dental practitioners. Although, studies have compared endodontists or endodontic residents with general practitioners for their decision making and quality of root canals but we have appraised this quality of endodontic care with a different approach. Whitworth et al. ^[3] showed that there was a significant difference in the endodontic practice and among dental graduates of 70’s compared to a younger group (graduates of 90’s) from British dental colleges (n=643 participants). This kind of compassion is not applicable in our scenario because there were only a few dental institutions in Pakistan before 1990 and the dental community in Pakistan is mainly a young cohort (median age 35 years). However, we speculated that there would be significant difference between dentists belonging to academic institution (irrespective of their specialty training) compared to general practitioners. This has stemmed from the observation that a considerable proportion of dentists do not adhere to the stated guidelines on the quality of root canal treatment⁴.

The professional education, advanced training and practice environment appear to be major determinants of clinical decision making in dentistry. Other important factors are individual preferences, availability of resources and clinical workload. There are two major avenues that provide dental care to the public; private dental clinics and the dental institutions. Cost effectiveness and time restraints are the two important factors that dictate the decision making in private practice. Therefore, we hypothesized that the endodontic services vary with the type of the clinical setup. Thus, it’s imperative to map the endodontic practice.

OBJECTIVE

The objective of the study was to compare the knowledge regarding endodontic materials and techniques selection among dentists employed at dental institutions and private practices in Karachi.

METHODOLOGY

Across sectional study was done at twelve dental colleges and their affiliated teaching hospitals in Karachi and selected private dental practices located in Karachi. We included PMDC registered dentists and excluded ones whose information was incomplete or deemed retired or deceased.

Pakistan Dental Association Karachi office provided the list that served as sampling frame. The data was last updated in 2007. A stratified random sampling approach was used to select the study participants in teaching and non-teaching groups. WHO sample size software was used and a sample size of 75 teaching dentists and 220 non-teaching dentists was calculated. Aga Khan University Hospital ethical review committee approved the protocol (573-Sur/ ERC-06). The informed consent of the participants was taken. A structured, selfadministered questionnaire (written in English) regarding preferences, selection of materials and techniques was used. The questionnaire had two parts:

• First part dealt with demographics (independent variables)
• Second part had 11 questions on endodontics practice (response variables).

Data Collection: Questionnaires were circulated to the study subjects by hand. A telephonic reminder was made at an interval of 2 weeks for non-responders. A second reminder was made at an interval of four weeks then collection of questionnaire was done. Two questions were repeated at the end to establish the information reliability.

Data Analysis: SPSS 19.0 was used for the data analysis. Means and standard deviations of the quantitative variables and proportions for the categorical variables were determined. The response variables in the study were about the preferences in material and clinical technique selection. These responses are measured on nominal or ordinal scale.

Independent sample t-test was applied to compare numerical variables (age and experience of the participants). Chi Square test (or Fisher’s exact test) was applied to determine if endodontic knowledge and material selection are different for the two groups. For the ordinal data, Mann-Whitney U test was used. A p-value less than 0.01 was taken as statistically significant. Kappa statistic was used to determine percent agreement between the first and second response on the two repeated questions.

RESULTS

In the teaching groups, 71 out of 75 (94.6%) responded while in the practitioners group, only 97 out 220 (44.1%) returned the forms. Both groups showed comparable result for age (p-value 0.1) and years of experience (p-value 0.07) as exhibited in table 1.

Table 2 displays that out of 168 participants; there were 71 (42.3%) teaching and 97 (57.7%) non-teaching dentists. There were more males in either group.

The decision making in routine Endodontics (table 3) was significantly different for the two groups. This included use of engine driven endodontic equipment, Gates-Glidden burs, irrigants selection, use of intra canal medicaments, use of endodontic sealer and preferred obturation technique (p-value < 0.001). More teachers

used engine driven endodontic equipment and GatesGlidden burs than private practitioners. A larger proportion of private practitioners used peroxide irrigant, puperyle and eugenol based intra canal medicaments and ZOE based endodontic sealer than the teaching dentists (p-value < 0.001). In addition to cold lateral compaction technique for obturation, more teachers utilized utilize warm vertical, warm lateral or thermoplasticized gutta percha than the practitioners (p-value < 0.001).

With regards to the decision making in surgical endodontics and restoration of root  treated teeth (table 4), the two groups had differences between them regarding core build up material selection (p-value < 0.001), decisions about failed root canals (p-value < 0.001) and method of gaining retention on root treated teeth (p-value < 0.001). However, the two groups were similar in their preference for core build up technique selection (p-value 0.04) and flap design selection for periapical surgery (p-value 0.89). The reliability of our study data was excellent, Kappa value 0.81 to 0.88 (table 5).

DISCUSSION

Whitworth et al.³ did a survey amongst two groups of dentists, an older group (graduates of 70’s) and a younger group (graduates of 90’s) from British dental colleges (643 participants). Questions were asked on use of rubber dam, selection of irrigant and factors influencing endodontics practice. The response rate was 85%. Investigators observed that the local anesthetic was the most commonly used endodontic irrigant. Irrigant selection was strongly associated to the use of rubber dam and to the graduation cohort. About 75% of rubber dam users irrigated with sodium hypochlorite, compared with only 38% of nonusers. This pattern was reversed for local anesthetic irrigation i.e. younger graduates more likely to irrigate with local anesthetic than their older counterparts. Our study results are somewhat different than Whitworth’s survey as 70-73% respondents reported hypochlorite as preferred irrigant and we did not find any association between age of the participant and irrigant selection. The probable explanation of this finding is that in our sample constituted of mainly young subjects in both the study arms (mean age of nearly 33 years in each group). With the relative absence of older age dentists in the study, any association of irrigant use with dentist age is meaningless.

Wilson & Christensen⁵ investigated on endodontics practice in England and Scotland. They sent questionnaire to 1,000 randomly selected dentists and obtained 70% response rate. The most commonly used obturation technique was the cold lateral condensation (75%). Our results are in accordance with Wilson & Christenson as 75-95% of our respondents reported cold lateral compaction as their preferred obturation technique.

In our study, calcium hydroxide and pulperyle was the predominant intra-canal medicament. About 75-80% of our respondents favored calcium hydroxide based sealer along with obturation whereas only 8-23% selected ZnO based sealers. Jenkins & Hayes⁶ who collected information from the dental graduates of Cardiff, UK with a study response rate of 41.5% reported that antiseptic solution was the most preferred interappointment medicament in UK. Two-thirds of practitioners in UK used a zinc oxide based material as their root canal sealer. Thus, dentists in Pakistan have significantly different preferences than dentists in UK regarding root canal sealers.

Slaus & Bottenberg⁷ studied routine endodontics performed by 4,500 Flemish dentists (Belgian belonging to dutch background) and obtained 25% response rate. The most preferred root canal irrigant was sodium hypochlorite. AH26- resin based sealer was the most prevalent and nearly 80% dentists reported that they performed re-treatments. Our sample is different from Flemish dentists as only 1-5% of Pakistani dentists use resin based sealer and only 27-34% reported carrying out endodontic re-treatment themselves.

Hommez & Braem⁸ and Hommez & De Moor⁹ obtained information on root canal treatment in Belgium: A questionnaire was distributed to 312 dentists in Flemish Universities. Data on various issues relating to endodontics was gathered. The response rate was 99%. The results of this study indicate that the theoretical knowledge of dentists is good. They reported that approximately one-third of the dentists did not use any intra-canal medicament. Cold lateral condensation of gutta-percha was the widespread obturation method employed by the respondents (65.8%). Resin-based

sealers were prevalent (88.6%). The findings of Hommez & colleagues 8-9 on root canal obturation technique and endodontic referrals are somewhat very close to our Pakistani data except that resin based sealer are not favored here.

Ahmed & colleagues¹⁰ evaluated the endodontic practice in Sudan. Fifty-two dentists responded to questionnaire. Nearly 80% respondents selected hydrogen peroxide as the irrigant of choice and around 75% dentists used formocresol as an inter-appointment medicament. Almost all dentists used hand instruments to prepare root canals.  Cold lateral condensation was the most favored obturation technique (75%). It’s evident that Pakistani dental practitioners exhibited significantly different choices in endodontic practice than Sudani dentists. About 43-60% of our dentists routinely use Engine driven rotary endodontic instruments and the numbers are continuously rising.

Our study showed that the two study groups exhibited entirely different choices in Surgical Endodontics and restoration of endodontically treated teeth, core build up material, decisions about failed root canals and method of gaining retention on root treated teeth (p-value < 0.001). However, they were similar in flap designing for surgical endodontics.

Our study results can be compared to a number of studies^4-10 on this subject but it would be irrelevant to compare our local data to developed countries where the prevalence of dental diseases and hence demand of dental services may be different. Availability of material resources can be factor for inappropriate decision making in some clinical scenarios in our study. However, our study has the advantage that it has included both the conventional and surgical aspects of endodontics. It’s a high time for dentists to engage themselves in a life long continuing education to predictably carry out goodquality dentistry.

STRENGTHS & LIMITATIONS

The response rate from the non-teaching group (44.1%) appears low but upon exploring into the reasons behind this feeble response rate, it’s revealed that the busy clinical practitioners are not interested in filling out questionnaires & proformas during work hours. On similar studies, Jenkins⁶ in UK had a response rate of 41.5% and Slaus⁷ had a response rate of 25% in Belgium. This proposes that it’s not uncommon for practicing dentists to give low response rate on such questionnaires^11-12 in this context; our response rate of 44.1% does not appear that weak. Since, the detailed demographic information of non-responding subjects was not available, so we could not explore any further in this direction. This non-response has the potential to give rise to biased results.

In comparison to the practitioners, the teaching group showed a better compliance in responding to the questions. Probably they were more conversant to research activities and hence unruffled in participation. Our study included dentists from all dental colleges except one because that particular dental institution refused the permission for distribution of questionnaire.

CONCLUSIONS

. The two groups of dentist showed similarities in selection of irrigants as they both preferred sodium hypochlorite for irrigation. The obturation technique for both groups was cold lateral compaction. Flap design selection for periapical surgery was also common for the two groups. Similarly, amalgam remained the material of choice for core build up in both the groups. . However, there were significant differences in the following parameters: Teaching group favoured calcium hydroxide based endodontic sealer while practitioners favoured ZnO based sealer. The decision making about failed root canals and method of gaining retention on root treated teeth were different as teaching dentists favoured more crown lengthening and attempted periapical surgery more frequently than the non-teaching dentists.

RECOMMENDATIONS

Re-validating the dental practice license after accumulating required numbers of continuing professional development hours should be made a mandatory requirement for practicing dentistry.

REFERENCES

1. Torabinejad M, Walton RE. Endodontics: Principles and Practice 4th ed. Mosby Elsevier, St Louis, MO, 2011.
2. Mounce R. The biologic objectives of root canal therapy: meeting the standard. Compend Contin Educ Dent. 2004; 25: 578-581.
3. Whitworth JM, Seccombe GV, Shoker K, Steele JG. Use of rubber dam and irrigant selection in UK general dental practice. Int Endod J. 2000; 33: 435-441.
4. Peters OA. Current challenges and concepts in the preparation of root canal systems: A review. J Endod
   2004; 30: 559-597.
5. Wilson NH, Christensen GJ, Cheung SW, Burke FJ, Brunton PA. Contemporary dental practice in the UK: aspects of direct restorations, endodontics and bleaching. Br Dent J. 2004; 197:753-756.
6. Jenkins SM, Hayes SJ, Dummer PM. A study of endodontic treatment carried out in dental practice within the UK. Int Endod J 2001; 34: 16-22.
7. Slaus G, Bottenberg P. A survey of endodontic practice amongst Flemish dentists. Int Endod J. 2002; 35: 759-
   767.
8. Hommez GM, Braem M, De Moor RJ. Root canal treatment performed by Flemish dentists. Part 1. Cleaning and shaping. Int Endod. 2003; 36:166-173.
9. Hommez GM, De Moor RJ, Braem M. Endodontic treatment performed by Flemish dentists. Part 2. Canal filling and decision making for referrals and treatment of apical periodontitis. Int Endod J. 2003; 36: 344-351.
10. Ahmed MF, Elseed AI, Ibrahim YE. Root canal treatment in general practice in Sudan. Int Endod J. 2000;
    33: 316-319.
11. Khan FR, Mahmud S, Rahman M. Pediatric dentistry training for dentists in Pakistan. J Pak Dent Assoc 2013;
    22: 03-08.
12. Khan FR, Mahmud S, Rahman M. Is there a difference in Operative Dentistry Care offered by teaching versus non-teaching dentists? J Pak Dent Assoc 2014; 23:30-35.

1. Assistant Professor, Operative Dentistry Dental Clinics, JBHS Building Aga Khan University & Hospital Stadium Road, 74800, Karachi.
2. Associate Professor, Department of Community Health Sciences Aga Khan University, Karachi.
3. Senior Lecturer, Operative Dentistry Dental Section, Aga Khan University, Karachi.
Corresponding author: “Dr Farhan Raza Khan ” < farhan.raza@aku.edu  >