Although dental implants have revolutionized prosthetic dentistry, the conventional complete denture remains the most popular treatment option for edentulism. ^[1] Edentulous individuals who use complete dentures adapt by acquiring the necessary oral motor skills to ensure optimal function during regular movements such as speech and mastication. ^[1] The successful performance of maxillary and mandibular dentures largely depends on the combination of the patient’s general oral functions and the psychological acceptance of their denture. ^[2,3] This acceptance is influenced by the denture’s stability during mastication and other oral functions, as well as the patient's satisfaction with their facial appearance. For a complete denture to function effectively, it requires accuracy and efficiency in every step of its fabrication. ^[4] However, some edentulous individuals report difficulties related to mastication and speech, and poorly fitting dentures can accelerate the process of resorption, further complicating the patient’s oral health and function. ^[3]

Achieving optimal retention and stability in complete dentures presents several challenges, influenced by various factors such as adhesion and cohesion, viscosity and flow of saliva, and the shape and degree of resorption of the alveolar ridges. The quality and quantity of alveolar bone  also play a crucial role in determining the fit and function of the dentures. ^[5,6,7,8,9] Precision in fabrication begins with an accurate impression of the appropriate anatomic landmarks and denture-bearing areas. ^[4] The dimensional accuracy of the impression material is significantly influenced by the technique used, which affects the final outcome.[10] Inaccuracies during impression making are often transferred during the prosthesis fabrication process, potentially resulting in laboratory errors and misfit dentures. These factors directly impact the overall fit and retention of the dentures, which are essential for patient satisfaction and functional success. ^[11] Therefore, ensuring accurate impression techniques and careful fabrication is critical for achieving effective and comfortable dentures for edentulous patients.

Border molding is a fundamental procedure in prosthetic dentistry that ensures a well-adapted and stable denture fit by closely adapting the impression tray to the vestibular tissues before securing the final impression. ^[12] This step is essential for achieving proper retention, as it helps create precise borders that conform to the patient’s oral anatomy. ^[13] Traditionally, modeling compound has been widely used for border molding and remains a key component in dental education. However, the process can be time-consuming, particularly for dental students, as it often requires multiple insertions to achieve the desired adaptation. To enhance efficiency, alternative materials such as silicone and polyether impression materials have been introduced. ^[14] Studies have demonstrated that using high-viscosity silicone for border molding, followed by a low-viscosity material for the final impression, yields superior results compared to conventional low-fusing impression compounds. ^[15] Additionally, polyether impression materials allow for border molding to be completed in a single insertion, simplifying the process and improving ease of use. ^[16] Since the success of a complete denture depends on multiple technical, biological, and physiological factors, precise border molding plays a critical role in denture longevity and patient satisfaction. ^[17,18] The selection of appropriate materials and techniques can significantly influence the final outcome, ensuring optimal retention and function.

Your study aims to evaluate the effect of border molding accuracy on the stability and retention of complete dentures. Additionally, it seeks to assess how accurate border molding influences patient satisfaction and denture movement, offering insights into its role in enhancing overall prosthetic outcomes. This research is crucial for improving denture fabrication techniques and ensuring better functional and aesthetic results for edentulous patients.

OBJECTIVE

The aim of the study was to evaluate the effect of border molding accuracy on the stability and retention of complete dentures.

This observational, comparative study was conducted at the Department of Prosthodontics, Bangabandhu Sheikh Mujib Medical University (BSMMU), and beau-dent, Dhaka, Bangladesh between January 2010 and December 2010. A total of 30 patients were included in the study, who were selected based on specific inclusion criteria for the evaluation of the impact of border molding accuracy on the stability and retention of complete dentures.

Inclusion Criteria:

• Patients who required complete dentures for both upper and lower arches
• Willingness to participate in the study

Exclusion Criteria:

• Patients with uncontrolled systemic diseases
• Patients with severe ridge resorption or anatomical abnormalities that would affect denture retention
• Patients who had received treatment with other prosthetic restorations or undergone recent denture adjustments.

The study was conducted after obtaining written informed consent from all participants, ensuring their awareness of the study's purpose and procedures while maintaining confidentiality and anonymity. Each patient underwent a thorough clinical examination to assess their oral condition, followed by diagnostic impressions made using alginate material to prepare study models. Border molding was performed using custom trays and green stick compound, and its accuracy was evaluated by an experienced prosthodontist. Border molding was categorized as accurate (well-defined, stable borders adhering to soft tissues without underextension or overextension) or inaccurate (characterized by underextended borders, poor adaptation to soft tissues, or excess material leading to improper fit). Final impressions were made using zinc oxide eugenol (ZOE) impression material, and master casts were poured to fabricate complete dentures using standard protocols. Dentures were delivered to patients, with necessary adjustments made to ensure proper fit and comfort. Data collection included recording demographic characteristics (age and gender) and categorizing patients into two groups based on border molding accuracy: accurate border molding group (n = 15) and inaccurate border molding group (n = 15). Stability parameters were evaluated, including retention (resistance to vertical displacement), patient satisfaction (assessed using a 5-point Likert scale based on comfort, function, and overall satisfaction), and denture movement (categorized as minimal to none or significant during functional movements like chewing and speaking). Descriptive statistics were used to summarize demographic data, and chi-square tests were employed to compare stability parameters between the two groups, with a p-value of <0.05 considered statistically significant.

Table 1: Demographic Characteristics of the Study Population (n=30)

The table included 30 patients with a mean age of 64.9 ± 11.7 years. The majority of participants were aged 60-69 years (14 patients, 46.7%), followed by 50-59 years (6 patients, 20.0%), 70-79 years (5 patients, 16.7%), ≥80 years (3 patients, 10.0%), and <50 years (2 patients, 6.7%). In terms of gender distribution, 19 patients (63.3%) were female, while 11 patients (36.7%) were male.

Table 2: Accuracy of Border Molding in Study Participants (n=30)

Among the 30 patients in the study, 15 (50.0%) had accurate border molding, while the remaining 15 (50.0%) had inaccurate border molding.

Table 3: Comparison of Stability Parameters Between Accurate and Inaccurate Border Molding Groups (n=30)

This table summarizes the outcomes of key stability parameters in patients with accurate versus inaccurate border molding. The accurate molding group demonstrated significantly higher rates of stable retention (80.0%) and high patient satisfaction (86.7%) compared to the inaccurate group (33.3% and 46.7%, respectively). Additionally, the frequency of minimal denture movement was significantly greater in the accurate group (80.0%) than in the inaccurate group (33.3%). All differences were statistically significant, with p-values < 0.05, underscoring the impact of precise border molding on denture stability and patient outcomes.

This study investigates the impact of border molding accuracy on the stability and retention of complete dentures, focusing on its implications for prosthodontic care at a tertiary hospital in Bangladesh. Border molding, an essential step in the fabrication of complete dentures, directly affects the fit, retention, and overall function of the prosthesis. The findings reveal significant differences between accurate and inaccurate molding, with the former leading to enhanced stability, patient satisfaction, and minimal denture movement. These results emphasize the importance of precise border molding in achieving optimal denture outcomes and highlight the potential for improving patient quality of life through more refined prosthodontic techniques.

In our study, the mean age of participants was 64.9 ± 11.7 years, with the majority falling within the 60-69 years age group (46.7%). These findings are consistent with the results reported by Heydecke et al. ^[19], who documented a similar mean age of 69.1 ± 8.0 years among complete denture wearers, reinforcing the association between aging and edentulism. The gender distribution in our study showed a female predominance (63.3%), which aligns with the findings of Heydecke et al. ^[19], suggesting that female patients may require complete dentures more frequently than males (36.7%). This demographic trend may be attributed to variations in oral hygiene practices, tooth loss patterns, and healthcare-seeking behavior among different genders. The similarity in age and gender distribution between our study and previous research highlights the representativeness of our sample in assessing the impact of border molding accuracy on denture stability in an aging population.

The accuracy of border molding plays a crucial role in the overall fit and stability of complete dentures. In this study, an equal distribution of accurate and inaccurate border molding (50.0% each) was observed among the participants. This balance allows for a direct comparison of outcomes between the two groups, highlighting the impact of border molding precision on denture stability, patient satisfaction, and functional performance. Understanding the factors contributing to inaccuracies can help improve clinical techniques and enhance patient outcomes.

The findings of this study emphasize the critical role of accurate border molding in achieving optimal stability and patient satisfaction with complete dentures. Patients in the accurate molding group demonstrated significantly better retention, with 80.0% achieving a stable fit compared to only 33.3% in the inaccurate molding group (p = 0.010). This suggests that precise border molding contributes directly to improved adaptation of the denture base, leading to a more secure fit. In contrast, Appelbaum et al. ^[20] found no significant difference in retention across different impression techniques (p = 0.9864), highlighting a key distinction in study focus. While their research evaluated general impression methods, our study specifically assessed the impact of molding accuracy, which may account for the observed differences in outcomes.

Patient satisfaction was also markedly higher in the accurate molding group (86.7%) compared to the inaccurate group (46.7%), further reinforcing the clinical benefits of precision in denture fabrication. A well-retained and stable denture not only improves oral function but also enhances patient confidence and overall quality of life. These findings align with Čelebić et al.[21], who found that patients with higher quality denture-bearing areas reported greater comfort and satisfaction with their dentures. Collectively, these findings support the necessity of meticulous border molding techniques in clinical practice to optimize denture stability, minimize movement, and maximize patient comfort.

In addition to retention, denture movement was significantly lower in the accurate molding group, with 80.0% of patients experiencing minimal to no movement compared to only 33.3% in the inaccurate group (p = 0.011). These results align with Čelebić et al.[21], who found that patients with higher quality denture-bearing areas experienced significantly less denture movement and greater comfort. This correlation underscores the importance of accurate border molding in minimizing functional instability, as excessive movement can lead to patient discomfort, difficulty in chewing, and an increased risk of soft tissue irritation.

Limitations of the study

This study had some limitations:

• The study was conducted in a selected tertiary-level hospital.
• The sample was not randomly selected.
• The study's limited geographic scope may introduce sample bias, potentially affecting the broader applicability of the findings.

This study demonstrates the significant effect of border molding accuracy on the stability and retention of complete dentures. The results indicate that accurate border molding improves denture fit, reduces movement, and increases patient satisfaction compared to inaccurate molding. These findings emphasize the importance of precise border molding in achieving better clinical outcomes. Ensuring accuracy in this step can enhance both functional and comfort aspects of dentures, highlighting its vital role in successful prosthetic rehabilitation.

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