Primary tooth vital pulp therapy techniques taught in dental schools in Saudi Arabia: a cross-sectional study

2.1 Study design and setting

This is a nationwide, investigator-initiated cross-sectional study that focused on pediatric dentistry faculty members from all dental schools in Saudi Arabia. The reporting of this study follows the guidelines outlined in the strengthening the reporting of observational studies in epidemiology (STROBE) statement [17].

2.2 Dental schools and participants

To be eligible for participation, dentistry faculty members had to have a formal affiliation with an undergraduate dental school in Saudi Arabia, either as full-time or part-time faculty members. There were no geographical restrictions regarding the location of their training. Both male and female participants, aged 30 to 75 years, were considered eligible. We included private and public institutions as long as they offered undergraduate dental programs. Individuals who were unable to provide informed consent were excluded from the study.

2.3 Sampling

Participants were recruited for the study through a two-stage process. In the first stage, heads of dentistry departments were contacted via email, providing them with a detailed explanation of the study’s objectives. Additionally, a hyperlink to access the questionnaire was included in the email, along with a request to distribute the survey among the pediatric dentistry department faculty members. In the second stage, the initially eligible participants were internally contacted within the dental schools and personally invited to complete the questionnaire.

2.4 Questionnaire and variables

We developed a questionnaire based on a previous study [13] as the foundation for our research. Specifically, the questionnaire for this study encompassed various questions and topics concerning VPT techniques. Socio-demographic information, including age, gender, nationality, affiliation, and academic rank, was collected. Age was categorized into four groups: <35, 35–40, 41–45 and >45 years. The questionnaire was accessible for completion between January and June 2022.

We also gathered information pertaining to the respondents’ postgraduate pediatric dentistry clinical training. This included details about the institution where they received their training, the type of postgraduate training they underwent, and the year in which they obtained their training certificate. Furthermore, the questionnaire encompassed queries regarding IPC, such as the teaching and using materials like calcium hydroxide, zinc oxide, glass ionomer, and others. It also included questions concerning direct pulp therapy, specifically addressing the use of hard-setting calcium hydroxide, MTA, total-etch technique, glass ionomer cement (GIC), Ledermix paste, and other materials. The questionnaire further inquired about using various materials for vital pulpotomies, including ferric sulfate, formocresol, MTA, calcium hydroxide, laser, or no medicament. Participants were allowed to select multiple options when indicating the dental materials used. Additional questions focused on the choice of material for pulpotomy coverage, the type of restoration employed following a vital pulpotomy, and whether students were instructed to take a postoperative radiograph. Complete details regarding the questionnaire can be found in Supplementary material.

2.5 Statistical analysis

Assuming that 85% of the participants would teach indirect pulp capping [12], the study would require a sample size of 54 participants to estimate the expected proportion with a 10% absolute precision and 95% confidence intervals. The determination of the sample size was conducted using the G*Power software package (Version 3.1.9.4, Kiel University, Kiel, Germany).

Variables with an approximately normal distribution were summarized using means (standard deviations, SD), while variables with a skewed distribution were summarized using medians (interquartile ranges, IQR). Categorical variables were presented as numbers (percentages). Act 95% confidence intervals (95% CIs) for proportions were calculated using the Clopper-Pearson method. Exploratory analyses were conducted using logistic regression models to investigate the associations between the teaching of indirect or direct pulp capping and socio-demographic, institutional, and clinical training characteristics. In cases where zero events were observed, exact logistic regression was utilized. Statistical analyses were performed using SAS 9.4 software (SAS Institute, Inc., Cary, NC, USA). A two-sided p-value of less than 0.05 was considered statistically significant.

3.1 Characteristics of the participating institutions and dental professionals

Table 1 presents a summary of the key characteristics pertaining to the participating institutions and dental professionals. Out of the 27 dental schools in Saudi Arabia that were contacted, 17 of them participated, resulting in a participation rate of 74.1%. Among the participating institutions, 12 (71%) were public. The median (IQR) number of dental professionals per institution was three (2 to 4). Of the 77 participants, 40 (52%) were male, and the age group with the highest frequency was 35–40 years (36%). In total, 57 participants (74%) received pediatric dentistry training internationally, primarily from institutions in the United States and the United Kingdom.

3.2 Teaching of IPT for primary teeth

Among the 77 participants, 73 (95% CI, 87–99%) reported engaging in teaching IPT. Of these, 52 (71%) stated that they teach the utilization of GIC, while 44 (60%) reported teaching the application of calcium hydroxide. Additional information regarding the materials employed by dental professionals who teach IPT for primary teeth in Saudi Arabia can be found in Table 2.

3.3 Teaching of DPC for primary teeth

Out of the 77 participants, 11 (14%, 95% CI, 7–24%) reported teaching DPC. The most commonly employed materials were MTA, used by seven out of 11 participants (64%), and calcium hydroxide, used by six out of 11 participants (54%). Table 2 shows additional information about the materials utilized by dental professionals teaching DPT for primary teeth in Saudi Arabia.

3.4 Teaching of pulpotomy in primary teeth

Table 3 illustrates the preferences for medicaments used in pulpotomy procedures among dental professionals who teach in Saudi Arabia. Significantly diverse practices were observed in the selection of medicaments for pulpotomy in primary teeth. The most frequently utilized medicament was formocresol, with 65 participants (84%) reporting its usage, whereas biodentine was the least preferred option, mentioned by only one participant (1.3%).

When given the option to choose between two or more medicaments, 35 participants (45%) indicated that their preferred first choice would be MTA. The second most commonly selected option was formocresol, chosen as the first preference by 28 participants (36%).

Among the 77 participants, 62 (80.5%) preferred utilizing zinc oxide and eugenol cement as the material for placement over the pulp chamber. Regarding the final restoration following vital pulpotomy of primary teeth, all respondents (100%) favored using a stainless-steel crown.

Out of the 77 respondents, 34 (44.2%) indicated that they teach students to take a postoperative radiograph. Among those who instruct their student take x-rays, the majority (21, 67.7%) recommended taking the radiograph immediately after the restoration.

3.5 Factors associated with the teaching methods of VPT

Our analysis found no significant associations between the examined socio-demographic, institutional, and clinical training characteristics and the likelihood of teaching IPC (Table 4). However, when examining direct pulp capping (Table 5), we observed a significant trend indicating that older age categories had a higher likelihood of teaching DPC (odds ratio for trend: 2.27, 95% CI: 1.11–5.04, p = 0.02).

4.1 Principal findings

This nationwide survey, which achieved a participation rate of 74.1%, provides valuable insights into the current teaching practices of VPT for primary teeth among undergraduate dental schools in Saudi Arabia. According to our findings, 95% of dental professionals at Saudi dental schools teach IPC, predominantly utilizing GIC and calcium hydroxide as the preferred materials. In contrast, only 14% of faculty members reported teaching DPC, with the most commonly used materials being MTA and calcium hydroxide. Notably, formocresol emerged as the most frequently employed medicament for pulpotomy, although MTA was favored when presented with multiple medicament options. Our analysis revealed no statistically significant associations, except for age, which demonstrated a noteworthy correlation, indicating that older individuals were more inclined to teach DPC. Nevertheless, the magnitude of this association remains uncertain due to sparse data.

4.2 Comparison with previous studies

Several studies have been conducted globally to evaluate the teaching methods of VPT in undergraduate dental students at dental schools. However, to the best of our knowledge, none of these studies have specifically been undertaken in Saudi Arabia.

IPC, as a conservative approach to pulp therapy, prioritizes the preservation of tooth vitality. In our study, a significant proportion of participants expressed their preference for teaching IPC in the context of deciduous teeth. Moreover, most respondents favored using glass ionomer as the primary material, closely followed by calcium hydroxide. Notably, these findings are in line with several studies conducted in the USA and Colombia [12, 15, 16].

In the present study, a substantial percentage (85.7%) of respondents did not include DPC as a treatment modality for primary teeth in their teaching practices. These findings are consistent with previous studies [12, 14, 15, 18]. Only 14.3% of our sample reported teaching DPC for primary teeth, which is relatively low considering the growing body of evidence supporting its efficacy [6, 19, 20, 21, 22]. However, this observation could be attributed to the recent statement by the AAPD indicating that DPC is not contraindicated for primary molars [6]. Interestingly, we observed a positive association between older age groups and a higher likelihood of teaching DPC. Several factors could explain why older dental professionals are more inclined to teach DPC. They may possess more experience with this technique, having been exposed to it throughout their careers. Additionally, their training may have occurred during a period when DPC was more commonly taught and practiced.

Several clinical studies have been conducted to evaluate the success rate of DPC for primary teeth. Ali et al. [19] conducted a clinical trial that reported a 74.7% success rate for DPC in primary molars after a 1-year follow-up. Similarly, a recent prospective randomized clinical trial demonstrated an acceptable success rate for asymptomatic carious primary molars at a 13-month follow-up, utilizing three biocompatible materials [20]. Additionally, Dimitraki et al. [21] found that both DPC and pulpotomy exhibited acceptable success rates, with no significant difference in failure rates between the two methods after a 3-year follow-up. A recent systematic review emphasized that with the availability of advanced biocompatible materials, there is no evidence supporting the contraindication of DPC in primary teeth [22].

In Saudi Arabia, the teaching of VPT places a strong emphasis on the pulpotomy procedure, which remains the most commonly taught technique. Notably, formocresol emerges as the predominant medicament employed, aligning with findings from studies conducted in the USA, Colombia, and Brazil [12, 15, 18]. However, our results differ from studies conducted in Europe [13], Ireland and the UK [14], which have shown a decline in the use of formocresol in recent years, with ferric sulfate emerging as the preferred alternative. This shift can be attributed to increasing concerns regarding the toxicity and carcinogenicity of formocresol. In 2004, the International Agency for Cancer Research classified formocresol as carcinogenic to humans, leading to a reduction in its usage and a surge in the adoption of alternative materials across Europe [23].

The widespread use of formocresol as the preferred medicament in many countries can be attributed to various factors, including its affordability and widespread availability. These aspects likely contributed to the high percentage of formocresol usage observed in our study, particularly considering that most dental schools in Saudi Arabia receive government funding. However, when participants were asked about the possibility of transitioning to a different medicament, most preferred using MTA as the alternative choice. It is important to note that the success of any pulp therapy heavily relies on a well-sealed coronal restoration. In our study, all respondents unanimously agreed that stainless-steel crowns are the preferred option for the final coronal restoration following pulpotomy of primary teeth. Numerous studies have demonstrated the superior survival rates of stainless-steel crowns compared to other types of restorations [24, 25].

4.3 Limitations

The present investigation has several limitations that should be acknowledged. First, the study utilized an online questionnaire, offering advantages such as cost-effectiveness and time efficiency. However, it is important to recognize that online surveys may exclude eligible participants who currently lack internet access or may not be inclined to respond to online questionnaires. While it is impossible to completely eliminate the possibility that non-participants may possess different teaching practices and characteristics compared to participants, the high participation rate achieved (74.1%) reduces the risk of selection bias. Second, the study relied on self-reported data, which can be susceptible to response bias. Participants may have either over or under-reported their teaching practices, potentially influencing the accuracy of the findings. Third, the study exclusively focused on faculty members in Saudi Arabia, limiting the generalizability of the findings to other countries or regions. Fourth, the study solely examined undergraduate pediatric dental courses, and therefore, the results may not apply to postgraduate education or other advanced dental courses. Fifth, the study did not investigate the quality of teaching or the clinical outcomes associated with the various techniques. Consequently, it remains unclear whether the reported teaching practices are associated with improved or compromised clinical outcomes. Sixth, the sample size of our study was small, resulting in limited statistical power and impeding our ability to establish robust predictors for teaching IPC or DPC. Seventh, the underlying causes of the observed variations in teaching practices were not explored. Further research is warranted to gain a deeper understanding of these variations, preferences, and predictors that impact the adoption of new pulp therapy medications. This will facilitate the identification of areas for improvement in dental education and clinical practice within Saudi Arabia.