This Article

Citations


Creative Commons License
Except where otherwise noted, this work is licensed under Creative Commons Attribution-NonCommercial 4.0 International License.

The Assessment of Dentists’ Knowledge Regarding Indications of Cone Beam Computed Tomography in Qazvin, Iran


1 Department of Oral Radiology, Dental Faculty, Qazvin University of Medical Sciences, Qazvin, IR Iran
2 Department of Oral Medicine, Dental Faculty, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
3 Department of Oral and Maxillofacial Surgery, Dental Faculty, Qazvin University of Medical Sciences, Qazvin, IR Iran
*Corresponding author: Mansour Khorasani, Department of Oral and Maxillofacial Surgery, Dental Faculty, Qazvin University of Medical Sciences, Qazvin, IR Iran. Tel: +98-2813353061, E-mail: vkhorasani1342@yahoo.com.
Biotechnology and Health Sciences. 2015 February; 2(1): e25815 , DOI: 10.17795/bhs-25815
Article Type: Research Article; Received: Dec 4, 2014; Accepted: Jan 18, 2015; epub: Feb 21, 2015; ppub: Feb 2015

Abstract


Background: Cone beam computed tomography (CT) has recently become effective for oral and maxillofacial imaging.

Objectives: The aim of this study was to assess the knowledge of dentists regarding cone beam computed tomography.

Materials and Methods: In this descriptive cross sectional study, a questionnaire regarding cone-beam computed tomography (CBCT) was distributed amongst 100 dentists (general and specialist) in Qazvin, Iran. Their level of knowledge was compared in each section on the basis of age, gender, years of employment and last educational status and analyzed by the SPSS software and Mann-Whitney test.

Results: Data analysis showed that 4% of dentists had very low, 16% had low, 50% had medium, 19% had good and 11% had in very good level of knowledge. The average of dentists’ knowledge was 57 ± 18. According to the statistical results, there was a significant difference between level of knowledge and age, years of employment and educational degree (P < 0.05). Age and years of employment had a reverse relationship with level of knowledge and specialists had greater awareness. There was no significant difference between level of knowledge and sex (P > 0.05).

Conclusions: Overall, dentists had an average level of knowledge for CBCT. It is recommended for qualification programs to be held for dentists to strengthen their awareness toward cone beam computed tomography.

Keywords: Knowledge; Dentist; Cone - Beam Computed Tomography

1. Background


Cone-beam computed tomography (CBCT) is a new technology, in which two-dimensional detectors and conical beam are used instead of fan X-rays in conventional computed CT. In this technique, volumetric data are collected by rotating of beam and detectors around the desired structure (1). The main advantage of CBCT is its high sharpness of axial images compared to conventional CTs (2). Ludlow and colleagues showed that CBCT dosages can be different according to the manufacturer company, type of machine, type of observer and level of elective exposure factors (3).


In the recent years, this technology has been used to prepare cross-sectional images from maxillofacial structures. Cone-beam computed tomography has less exposure time and cost compared to conventional CT. The beams rays are confined for head and neck only. Lower dosage of X-rays and ability to take different images from a certain structure and also possibility of reconstruction in sagittal and coronal views, all make CBCT a convenient technology (4-6). The disadvantages of CBCT are its low resolution of soft tissue and scattering beams from tooth tissue (6). Usual indications of CBCT in dentistry are implantation, orthodontic treatments, assessment of temporomandibular joint (TMJ), relationship of third mandibular molar with inferior alveolar nerve block and presence of tumors and cysts (7). Cone-beam computed tomography makes images by centralizing the X-ray beam with a conical form on a two-dimensional detector, which rotates 360 degree around the patients’ head to make images. Next the algorithm of conical beam is applied on this data, and thus the technologist can make reconstructions of the curve and two-planar with different thicknesses on each side and achieve clear and actual three-dimensional images from bone and tooth tissue (8-10).


According to the significance of CBCT in dental treatments, it seems that assessment of dentists’ awareness for indications of this system is important. There is only one research related to this subject which has been done at Ankara University among dental students (11).

2. Objectives


This study was done to assess the knowledge of dentists regarding indications of CBCT images during 2012 and 2013 in Qazvin city, Iran.

3. Materials and Methods


This study received an exemption from the Institutional Review Board (registration number: 591) of the dentistry faculty, Qazvin University of Medical Sciences. Out of 124 dentists, who received the self-administered questionnaires (Figure 1), 100 dentists participated in this research. The statistical society included both general dentists and specialists. The questionnaire was designed considering the studies of Kamburoglu et al. (11), which were done in two universities in Ankara (4). The questionnaire included demographic data (age, sex, years of employment, educational degree) and fifteen questions regarding the CBCT technology. The questions assessed the knowledge of dentists about indications of CBCT. There was no compulsion for answering the questionnaire and dentists were ensured, that the results of this study will be used only for educational purposes of the dental society and will not be used for evaluating the dentists.


In this pilot survey, analysis of data was done by the SPSS software version 11.5 (IBM, New York, NY) and Mann-Whitney and Kruskal-Wallis tests.


Figure 1.
Questionnaire for Evaluation Dentist’s Knowledge Regarding Indications of Cone-Beam Computed Tomography

4. Results


Dentists̓ relative frequency distribution for demographic data on the basis of age, gender, number of years for employment, educational degree, as well as frequency of distribution on the basis of knowledge are indicated in Table 1.


Note: Out of 124 questionnaires, which were distributed among dentists, 100 were answered.


Dentists̓ relative frequency distribution for the fifteen questions related to CBCT were as follows: Question 1: prescribing CBCT: 38 (38%) answers were correct and 62 (62%) were incorrect; Question 2: justifiability for indications of CBCT: 84 (84%) were correct and 16 (16%) were incorrect; Question 3: comparing CT and CBCT: 20 (20%) were correct and 80 (80%) were incorrect; Question 4: most common indications of CBCT: 83 (83%) were correct and 17 (17%) were incorrect; Question 5: CBCT and TMJ: 48 (48%) were correct and 52 (52%) were incorrect; Question 6: contraindication of CBCT: 82 (82%) were correct and 18 (18%) were incorrect; Question 7: indication of CBCT in root fractures: 79 (79%) were correct and 21 (21%) were incorrect; Question 8: CBCT and articular disc: 47 (47%) were correct and 53 (53%) were incorrect; Question 9: indication of CBCT for implant surgery in edentulous patients: 41 (41%) were correct and 59 (59%) were incorrect; Question 10: contraindication of CBCT in orthodontics: 75 (75%) were correct and 25 (25%) were incorrect; Question 11: contraindications of CBCT in implant surgery: 23 (23%) were correct and 77 (77%) were incorrect; Question 12: contra indication of CBCT: 65 (65%) were correct and 35 (35%) were incorrect; Question 13: comparing CBCT with orthopantomogram (OPG): 57 (57%) were correct and 43 (43%) were incorrect; Question 14: comparing CBCT with intraoral radiographies, 70 (70%) were correct and 30 (30%) were incorrect; Question 15: order for prescription, 39 (39%) were correct and 61 (61%) were incorrect.


The grading scales for evaluating the level of knowledge were as follows; 0 - 20 was considered as very low; 20 - 40 was considered as low; 40 - 60 was considered as average; 60 - 80 was considered as high, and 80 - 100 was considered as very high. Average level of knowledge was 57 ± 17, lowest mark was 13 and highest mark was 100; 80% had an average level of awareness.


A P value of < 0.05 obtained from the Kruskal-Wallis test showed that there was a significant difference between knowledge of different age groups. Mann-Whitney test was done for analyzing differences among subgroups; for less than 30 and 35 to 40 (P = 0.005), for less than 30 and above 40 (P = 0.021), 30 to 35 and 35 to 40 (P = 0.003), 30 to 35 and above 40 yeas (P = 0.02), there was a significant difference among subgroups. According to the mean and median of all groups, awareness was higher in the younger age groups. The Pearson’s correlation coefficient was used for further analysis of these two variables and confirmed the relationship between these two variables. Also r = -0.304 showed a reverse relationship, indicating that with increasing age there was decreasing knowledge (Table 2). The P value obtained from the Mann-Whitney test showed that there was no significant difference between knowledge of different genders (Table 3).


The P value of < 0.05 obtained from the Kruskal-Wallis test showed that there was a significant difference between knowledge of people with various numbers of years for employment. Mann-Whitney test was done for analyzing differences among subgroups; for less than 5 years of occupation and 10 to 15 (P = 0.002), and for less than 5 years and over 15 years (P = 0.045). According to the means and medians of all groups, awareness was higher in groups with lower number of years for employment. The Pearson’s correlation coefficient was used for further analysis of these two variables and confirmed the relationship between these variables. A P value of 0 showed that there was a relationship and r = -0.326 confirmed a reverse relationship between the two variables, indicating that as the number of years of occupation increase, there is a decrease in knowledge (Table 4). A P value of < 0.05, obtained from the Mann-Whitney test showed that there was a significant difference between knowledge and education degree. Means and medians confirmed that knowledge of specialists was more than general dentists (Table 5).


Table 1.
Demographic Characteristics of Dentists’ Relative to Cone-Beam Computed Tomography Knowledge

Table 2.
Comparison of Knowledge Scores by Age

Table 3.
Comparison of Knowledge Scores by Gender

Table 4.
Comparison of Knowledge Scores According to Number of Years for Employment

Table 5.
Comparison of Knowledge Scores by Educational Degree

5. Discussion


This study was done for evaluating dentists’ knowledge regarding cone beam computed tomography. One hundred dentists including general dentists and specialists participated in this descriptive cross-sectional study. Females and those aged 30 to 35 had maximum frequency, according to frequency distribution. Those aged less than 30 years had the maximum level of knowledge (61.4 %), and level of knowledge decreased with increase in age. The inverse relationship between age and knowledge could be because 1) technology of CBCT has only been used in the last ten years and 2) the most common usage of CBCT is for implantation and in Iran young dentists are more involved in this field. Regarding the level of knowledge on the basis of gender, no significant differences were found between males and females. This finding was similar to Kamburoglu’ research that evaluated dental student’s knowledge for CBCT (11), and assessment of dentists’ knowledge for prescribing conventional radiographies by Mahdizadeh et al. (12) and Ardakani et al. (5).


Regarding the number of years of employment, there was a significant difference in the knowledge of individuals with different numbers of years of employment; as the number of years of employment increased awareness decreased. This was similar to Bardal’s study comparing dentists that had graduated previously with those that had recently graduated regarding prescription of intraoral radiology and panoramic views (13). According to level of knowledge on the basis of educational degree, there was a significant difference between level of knowledge and educational degree; specialist had greater awareness compared to general dentists. This was similar to a study done by Mahdizadeh et al. (12), which showed that specialists had greater knowledge about CT and MRI compared to other convention intraoral radiographies. Cone-beam computed tomography has one of the most important roles for diagnosis in dentistry. This research showed that dentists in Qazvin city had an average level of knowledge regarding cone beam CT. It is recommended that qualification programs must be held for dentists to increase their awareness toward cone beam computed tomography. Dentists must gain more knowledge about indications and contraindications of CBCT.

Acknowledgments

The authors appreciate the financial support of this research by the Research Council of Qazvin University of Medical Sciences.

Footnotes

Authors’ Contributions: Co-authors helped in designing, analysis of the results and writing of the current manuscript.

References


  • 1. Bianchi SD, Lojacono A. 2D and 3D images generated by cone beam computed tomography (CBCT) for dentomaxillofacial investigations. CARS; 1998; Amsterdam. Elsevier; p. 792-7.
  • 2. Ito K, Gomi Y, Sato S, Arai Y, Shinoda K. Clinical application of a new compact CT system to assess 3-D images for the preoperative treatment planning of implants in the posterior mandible A case report. Clin Oral Implants Res. 2001;12(5):539-42. [PubMed]
  • 3. Ludlow JB, Davies-Ludlow LE, Brooks SL, Howerton WB. Dosimetry of 3 CBCT devices for oral and maxillofacial radiology: CB Mercuray, NewTom 3G and i-CAT. Dentomaxillofac Radiol. 2006;35(4):219-26. [DOI] [PubMed]
  • 4. Scarfe WC, Farman AG, Sukovic P. Clinical applications of cone-beam computed tomography in dental practice. J Can Dent Assoc. 2006;72(1):75-80. [PubMed]
  • 5. Ezoddini Ardakani F, Sarayesh V. Knowledge of Correct Prescription of Radiographs among Dentists in Yazd, Iran. J Dent Res Dent Clin Dent Prospects. 2008;2(3):95-8.
  • 6. Scarfe WC, Farman AG. What is cone-beam CT and how does it work? Dent Clin North Am. 2008;52(4):707-30. v [DOI] [PubMed]
  • 7. White SC. Cone-beam imaging in dentistry. Health Phys. 2008;95(5):628-37. [PubMed]
  • 8. Feldkamp LA, Davis LC, Kress JW. Practical cone-beam algorithm. J Opt Soc Am. 1984;1(6):612-9. [DOI]
  • 9. De Vos W, Casselman J, Swennen GR. Cone-beam computerized tomography (CBCT) imaging of the oral and maxillofacial region: a systematic review of the literature. Int J Oral Maxillofac Surg. 2009;38(6):609-25. [PubMed]
  • 10. White SC, Pharoah MJ. The evolution and application of dental maxillofacial imaging modalities. Dent Clin North Am. 2008;52(4):689-705. v [PubMed]
  • 11. Kamburoglu K, Kursun S, Akarslan ZZ. Dental students' knowledge and attitudes towards cone beam computed tomography in Turkey. Dentomaxillofac Radiol. 2011;40(7):439-43. [PubMed]
  • 12. Mahdizadeh M, Fazaelipour M, Namdari A. Evaluation of dentists’ awareness of how to prescribe correct radiographs in Isfahan in 2010-2011. J Isfahan Dent Sch. 2012;7(5):637-42.
  • 13. Bardal R, Rahimi R, Ahmadi Motamayel F. A Comparative Study of the Previously Graduated Dentists' Knowledge versus those Recently Graduated as to Proper Prescription of Interaoral Radiography and Panoramic Views. J Dent Shiraz Univ Med Univ. 2011;12(3):195-205.

Table 1.

Demographic Characteristics of Dentists’ Relative to Cone-Beam Computed Tomography Knowledge

Characteristic No. (%)
Gender
Male 47 (47%)
Female 53 (53)
Age
Less than 30 years 33 (33)
30 - 35 years 36 (36)
35 - 40 years 11 (11)
Over 40 years 19 (19)
Years for employment
Less than 5 years 54 (54)
5 - 10 years 22 (22)
10 - 15 years 13 (13)
Over 15 years 11 (11)
Educational degree
General 75 (75)
Specialist 25 (25)
Frequency distribution on the basis of knowledge
Very low 4 (4)
Low 16 (16)
Average 50 (50)
High 19 (19)
Very high 11 (11)

Table 2.

Comparison of Knowledge Scores by Age

Age Mean Median Standard Deviation P value
Less than 30 years 61.4 60 18 0.003
30 – 35 years 60.5 53.5 17.7
35 – 40 years 44.3 46 13.4
Over 40 years 49 46 15.9

Table 3.

Comparison of Knowledge Scores by Gender

Gender Mean Median Standard Deviation P value
Male 53.1 53.3 15.6 0.06
Female 59.8 60 19.5

Table 4.

Comparison of Knowledge Scores According to Number of Years for Employment

Number of Years for Employment Mean Median Standard Deviation P value
Less than 5 years 61.3 60 18 0.008
5 - 10 years 55.4 50 18
10 - 15 years 46 46.6 9
Over 15 years 49 46.6 19

Table 5.

Comparison of Knowledge Scores by Educational Degree

Educational Degree Mean Median Standard Deviation P value
General 70.4 73.3 18.6 0.000
Specialist 52.1 46.6 15.4

Figure 1.

Questionnaire for Evaluation Dentist’s Knowledge Regarding Indications of Cone-Beam Computed Tomography