Self-Reported Levels of Competence and Consistency in Removable Partial Denture Design Among Nigerian Clinical Dental Students and Recent Graduates: An Exploratory Survey

Abstract

Background:

Denture designs form an important component in both undergraduate and postgraduate examinations in Nigeria. It is a means of communication between the dentists and technologists. This study assessed self-reported levels of competence and consistency in removable partial denture design among clinical dental students and recent graduates. It also sought to determine the level of knowledge about denture design.

Methodology

The study was an online semi-structured questionnaire survey of 170 clinical dental students and dental house officers in ten dental schools in Nigeria. Data on participants' technical knowledge of denture design were retrieved on a five-point Likert scale. Self-perceived opinions on competence at denture designing were scored as good, fair, and poor. Data were summarized as frequencies and percentages. Chi-square was used to determine associations. The strengths of associations were tested by binary logistic regression. The level of statistical significance was set at p<0.05.

Results:

A total of 107 students (male: female = 59:48) and 63 house officers (male: female = 40: 23) participated in the study. The mean age of the students was 26±1,8 years, while the house officers were on average 28.1±2.1 years old. More house officers (84.1%) self-reported competence, and (74.9%) consistency in denture design drawing. There was a strong association between participants’ knowledge and consistency in denture design drawing. Participants’ competence and consistency were not associated with age or gender.

Conclusion:

The majority of the respondents self-reported competence and consistency, and demonstrated good levels of knowledge in partial denture design.

Introduction:

The role of self-assessments by learners in the development of actionable guidelines by educators for improved learning outcomes has been highlighted by Harris and Brown in their seminal textbook [1]. The role of denture design in the undergraduate removable prosthodontic curriculum can scarcely be overlooked. A recent Delphi study conducted among leading teachers of undergraduate prosthetic dentistry [2] classified surveying and the drawing of designs (writing of prescriptions) as being important competencies that should be attained by the graduating dentist.

Denture designs continue to be an important component of undergraduate examinations in Nigeria and form part of the membership examinations in the postgraduate colleges [3]. Denture designs also form a significant part of the communication between dentists and technologists [2,4]. There are several instances in the literature where the importance of the level of such communication on endpoints has been highlighted [5-8].

The teaching of Prosthetic Dentistry in Nigeria is fraught with several challenges [8,9]. The sparse number of specialists in prosthetic dentistry is a major hindrance to the teaching of the subject [9]. While it has been suggested that this lack of human resources may be mitigated by the visiting lecturer model, the effects of this model on different aspects of the undergraduate curriculum remain largely unexplored.

The attainment of improved endpoints in competency and consistency in the drawing of denture designs by Nigerian undergraduate dental students may be enhanced if trainers are equipped with information regarding the learners’ perception of their competence and consistency in drawing denture designs. These improved endpoints may also be facilitated by the trainer’s acquiring information about the factors the learners perceive influence their levels of competence and consistency. However, reports about the levels of competence and consistency at drawing denture designs among clinical students and freshly graduated dentists in Nigeria remain acutely unexplored. Self-reports from students and recent graduates may not only provide trainers with a baseline understanding of these parameters, but they may also boost the clinical confidence and quality of patient care of students and learners [8].

This study, therefore, sought to assess the self-reported levels of competence and consistency in removable partial denture design among clinical dental students and recent graduate dentists in Nigerian schools of dentistry. The study also sought to determine the level of knowledge about denture design possessed by respondents. The relationship between knowledge levels, respondents’ sociodemographic characteristics, and their self-reported competence and consistency was also assessed. The study objectives were achieved with an online questionnaire survey.

Materials and Methods:

Ethical approval was obtained from the Research and Ethics Committee of the Lagos State University Teaching Hospital (REF NO: LREC 06/10/1034). This study was an online semi-structured questionnaire cross-sectional survey of clinical year dental students and dental interns (house officers) in ten dental schools within Nigeria. These dental schools included the following institutions: Lagos State University Dental School, University of Lagos Dental School, University College Hospital Dental School, Ibadan, Obafemi Awolowo University Dental School, Ife, University of Benin Dental School, Bayero University Dental School, Kano, University of Maiduguri Dental School, University of Port Harcourt Dental School. University of Nigeria Dental School and the University of Calabar Dental School. All the dental schools with clinical dental students and dental house officers within the period October 2021 to October 2022 were included in the study. The 17-question questionnaire was pretested on 5 randomly selected students and 3 house officers from three different centers before adoption. The questionnaire retrieved data related to participants’ sociodemographic characteristics, self-reported perception of competence and consistency, and participants’ knowledge of denture designs.

Participants’ knowledge of the denture design process was assessed by questions related to the technicalities of denture designing, like the role of undercuts, placement of clasp assemblies and connectors, and the sequencing of the design process. Responses were retrieved on a 5-point Likert scale from strongly disagree to strongly agree. A response of strongly agree or agree was deemed to show good knowledge, while other responses showed poor knowledge. Competence and consistency were assessed by directly asking for the respondents’ opinions on a 5-point scale from very poor to excellent.

The online questionnaires were gated at the point of consent, and participant data were only available after submission. Responses were submitted directly to the statistician, who was independent from the study and whose electronic address served as the host for the online survey. Investigators were completely blinded to the data collection process and only became aware of the results after the statistician provided them with a report.

A minimum sample size of 152 participants was determined from an estimated population of 140 (20 students and 5 house officers from each of the 10 centers) at 95% confidence interval, 5% margin of error, and 50% population proportion with the electronic application sample size calculator (https://www.calculator.net>sample-size). The questionnaires were administered through the online portal Google Forms via a convenience sampling technique. All responses were complete and unambiguous. The retrieved data were entered into an electronic spreadsheet and summarized as frequencies and percentages. Associations were demonstrated with the Chi-square test, and the strengths of associations were tested with logistic binary regression. The level of statistical significance was set at p≤0.05. The study design and reporting were in tandem with STROBE guidelines for reporting observational Studies.

Results:

A total of 170 individuals (107 undergraduates and 63 house officers) participated in the study. There were 59 (55.1%) male students and 48 (44.9%) female students, while there were 40(63.5%) male house officers and 23 (36.5%) female house officers. The mean age of the students was 26±1,8 years, while the house officers were on average 28.1±2.1 years old. The students in year six were about twice as numerous as those in year five. However,5(4.7%) of the students did not specify the year of study they belonged to. Participant sociodemographics are summarized in Table 1.

Table 1:

Demographic characteristics of the study participants

	Undergraduates		Dental Officers
Variable	Freq (N=107)	Percent (%)	Freq (N=63)	Percentage (%)
Age Group (Yrs)
≤ 25	44	41.1	4	6.3
26 – 30	61	57.0	54	85.7
>30	2	1.9	5	7.9
Age range	23 – 31	25 – 34
Median Age	26	28
Mean ± SD	26. ± 1.8	28.1 ± 2.1
Sex
Male	59	55.1	40	63.5
Female	48	44.9	23	36.5
Level of Education
Year Five	33	30.8	N/A	N/A
Year Six	69	64.5	N/A	N/A
Non-Response	5	4.7	N/A	N/A

Sixty-seven (62.6%) self-reported competence at denture design drawing, while a similar figure (64/59.8%) reported consistency in this endeavor. However, a higher proportion of house-officers 84.1% self-reported competence, and 79.4% self-reported consistency in denture design drawing. Paradoxically, a higher proportion of the students 71.7% exhibited good knowledge compared to 60.3 % of the house officers. Table 2 summarizes the competence, consistency, and level of knowledge exhibited among participants.

Table 2:

Competence, consistency, and knowledge of study participants

	Undergraduates		Dental Officers
Variable	Frequency	%	Frequen cy	%
Competent	67	62.6	53	84.1
Non-Competent	40	37.4	10	15.9
Consistence	64	59.8	50	79.4
Non-Consistence	43	40.2	13	20.6
Good knowledge	76	71.7	38	60.3
Poor knowledge	31	18.3	25	39.7

There was a moderately strong association between possession of good knowledge and competence at denture design drawing (p=0.031). Similarly, there was a strong association between participants’ knowledge and consistency in denture design drawing. Participants’ age and gender did not exhibit a statistical association with either competence or consistency at denture design drawing. The relationship between participants' age, gender, and level of knowledge with their self-reported competence and consistency is summarized in Table 3.

Table 3:

Relationship between age, gender, and level of knowledge with participants’ competence and consistency

	Competency (Freq (%)			Consistency (Freq (%)
Variable	Competent	Non competent	P-Value	Consistence	Non consistence	P-Value
Age grp (yrs)			0.583			0.726
≤25	33(68.8)	15(31.3)		31(64.6)	17(35.4)
26 – 30	83(72.2)	32(27.8)		79(68.7)	36(31.3)
>30	4(57.1)	3(42.9)		4(57.1)	3(42.9)
Gender			0.186			0.356
Male	73(73.7)	26(26.3)		68(68.7)	31(31.3)
Female	47(66.2)	24(33.8)		46(64.8)	25(35.2)
Knowledge			0.031*			0.011*
Good	93(75.0)	31(25.0)		90(72.6)	34(27.4)
Poor	27(58.7)	19(41.3)		24(52.2)	22(47.8)

The possession of good knowledge was fairly equally spread among the genders. Forty-two (39.3%) of male students, as well as 34 (31.8%) of female students, reported possession of good knowledge. Similarly, 21 (33.3%) of male house officers, and 17 (27.0%) of female house officers reported possession of good knowledge.

A binary logistics regression after adjustments for age and gender revealed a two-fold likelihood {Adjusted odds ratio 2.171 at (1.054-4.475) 95% confidence interval} of good knowledge predicting competence. This two-fold relationship was also present (although stronger) with consistency at denture design drawing {Adjusted odds ratio 2.453 at (1.210-4.971) 95% confidence interval}. The strengths of association between participants’ knowledge, sociodemographic, and level of competence and consistency in denture design drawing are summarized in Table 4.

Table 4:

Strengths of association between participants’ knowledge, competence and consistency

	Competency		COR (95% C.I)	AOR (95% C.I)
	Yes	No
Knowledge
Good	93	31	2.111(1.034 – 4.311)	2.171(1.054 – 4.475)
Poor	27	19
Age
≤25	33	15	1.130(.547 – 2.334)	1.084(.516 – 2.277)
>25	87	35
Gender
Male	73	26	1.434(.737 – 2.788)	1.521(.772 – 2.999)
Female	47	24
	Consistency		COR (95% C.I)	AOR (95% C.I)
	Yes	No
Knowledge
Good	93	31	2.426(1.205 – 4.887)	2.453(1.210 – 4.971)
Poor	27	19
Age
≤25	33	15	1.167(.578 – 2.358)	1.096(.532 – 2.256)
>25	87	35
Gender
Male	73	26	1.192(.625 – 2.275)	1.271(.655 – 2.464)
Female	47	24

COR= Crude odd Ratio, AOR= Adjusted odd ratio, CI = Confidence Interval

Discussion:

Denture designs integrate the cognitive and psychomotor spheres of knowledge in partial denture prosthodontics [10]. The drawing of these designs has been described as being both complex and variable [11]. However, it is generally acknowledged that drawing denture designs is not a haphazard endeavor, but an activity that is governed by a set of rules [12]. These qualities inherent in denture design drawing lend themselves to examiners at preclinical and postgraduate levels of training [13]. This also makes it imperative for the conscientious trainer to continuously evolve novel approaches to generating improvements in learning outcomes [14]. The role of self-reports from students has been severally highlighted in the literature [2,15].

The gender variation within our cohort is interesting. There was a clear male preponderance among the house officers. This is in keeping with previous reports about gender distribution among Nigerian dentists. Ogunbodede had reported a male preponderance among Nigerian dentists [16]. This finding was replicated in the study by Ikusika et al among dentists in private settings within Nigeria [17]. However, Chukwukah and Umweni noted a steady increase in the enrollment of female dental students [18]. Their study, published in 2017, predicted a gradual closing of this gap [18]. The figures we found among the dental students (where male students were only marginally more numerous than female students) seem to suggest this. There may be several factors that have influenced this. It would be interesting to explore these factors and harness the maximum benefits from them.

The higher rates of self-reported competence in denture designs among house officers may be due to reported improvements in skill acquisition with experience among dentists. Patel and co-workers documented this trend among British vocational dentists and their trainers [19]. This may have also been a fallout from the increased level of confidence they may have obtained after their final examination.

The higher levels of knowledge about denture designs by the undergraduate students appear paradoxical on the surface. However, when this is viewed from the perspective of recall and knowledge retention, this observation becomes clearer. Recall is often a function of short-term memory. This is different from longterm knowledge retention [20]. The majority of our cohort were final year students who would be preparing for their final examinations (where denture designs are a prominent component). They would thus be more likely to regularly familiarize themselves with the theoretical aspects of denture design. Bechtold et al. drew attention to the need to structure training and testing towards the acquisition of retained knowledge by trainees [21]. Our trainers must develop new strategies towards achieving this noble aim. Singh and coworkers suggested an incremental presentation of the subject matter to trainees as one of such strategies [22].

The synergistic relationship between the possession of good cognitive knowledge and the performance of psychomotor skills by Nigerian dental students has been reported by Ikusika et al [9]. The similarity of our findings suggests that this may be a feature of the Nigerian prosthetic dental education space. This should encourage our trainers to base the teaching of denture designs on a sound theoretical basis. The theoretical instructions may also be more effective if the students are active participants in such lessons. This may take the shape of a student-centered learning model [9].

The exploratory nature of this study prevents us from making any direct comparisons with other studies. This challenge is further worsened by a complete lack of local studies specifically addressing denture designs among undergraduates. However, in a similar manner to Wildgoose, this study also found increasing levels of competence and consistency with experience [23]. Mongkolrattanasi et al attributed the lower competence and consistency levels among inexperienced students to the transition between the acquisition of theoretical concepts and clinical application [24]. Nassief et al corroborated these findings and postulated that students find the transition from theory to practice especially difficult in complex cases [25].

This study, being exploratory in nature, may suffer some pitfalls when it comes to generalization of the study results. Williams has pointed out that exploratory studies tend to be rather ambiguous and difficult to generalize conclusions from [26]. Drew also corroborated this by drawing attention to the limited scope of such studies due to a tendency to over generalize when conducting these studies [27]. However, Drew acknowledged that exploratory studies still remain a valuable source of baseline information on which future research may be based [27].

Conclusion:

The majority of study participants self-reported competence and consistency in the drawing of partial denture designs. Similarly, the majority of respondents demonstrated good knowledge levels of denture design. Respondents with good knowledge were twice as likely to be competent and consistent at denture design drawing. Competence and consistency were not significantly affected by participants' age or gender.

Recommendations:

The teaching of denture designs must be based on a firm theoretical base designed to produce knowledge retention in the students. Students should be maximally exposed to clinical situations in addition to theoretical learning.