Attitude of dental professionals toward cast partial denture: A questionnaire survey in India

Evaluation and comparison of retention and patient satisfaction with milled polyetheretherketone versus metal maxillary obturators

STATEMENT OF PROBLEM

Metal and polyetheretherketone (PEEK) have been used to rehabilitate maxillary defects with obturators, each having advantages and disadvantages. However, patient satisfaction with the obturator retention of each material is unclear.

PURPOSE

The purpose of this crossover clinical study was to compare retention and patient satisfaction between a milled cobalt chromium and a milled PEEK framework, each with a hollow bulb extension in polymethyl methacrylate (PMMA).

MATERIAL AND METHODS

Twenty patients who had received unilateral total maxillectomy and were treated in the prosthodontic department's maxillofacial clinic were enrolled in this crossover study. Each participant wore 2 different types of obturators for 6 months after insertion. Type CoCr received a milled cobalt chromium framework with a hollow bulb extension in PMMA first, and type Pk received a milled modified PEEK (BioHPP) framework with a hollow bulb extension in PMMA first. Patient satisfaction and retention force were measured immediately, at 3 months, and at 6 months after obturator insertions. The Fischer exact, chi-squared, and Monte Carlo tests were used to compare qualitative data. One-way ANOVA with the post hoc Tukey test was used for pair-wise comparison, and repeated measures ANOVA was used to compare before and after treatment at 3 and 6 months.

RESULTS

No significant difference was found between types in obturator insertion (P>.999), appearance of the upper lip (P>.999), mouth feeling (P=.301), pronunciation of words (P=.217), and talking in public (P=.589). A significant difference between types was found in speech after 6 months of obturator insertion (P=.016), swallowing liquids and food (P=.04), masticating foods (P=.007), appearance of clasps on anterior teeth (P=.002), satisfaction with appearance (P=.005), or avoidance of family events (P=.014) after 6 months of insertion. Types of obturators showed a statistically significant decrease in retention force with time (P<.001).

CONCLUSIONS

Although the retention force was less with PEEK than with Co-Cr clasps engaging the same undercuts, this retention force was adequate for retaining removable partial dentures. Co-Cr clasps can be considered better than PEEK clasps because they engage the same undercuts regarding loss of retention with time. Quality of life in patients after maxillary resection could be improved by using maxillary obturators. Type Pk was better than type CoCr in terms of esthetics, but the retention of the PEEK obturator after 6 months decreased because of wear, leading to difficulty swallowing food or liquids, mastication, and speech.

Nonmetal clasp dentures: What is the evidence about their use?

The aim was to discuss the indications, contraindications, advantages, and disadvantages of Nonmetal clasp dentures (NMCDs), as well as the most relevant properties of its constituent materials. A search was conducted using the keywords: “nonmetal clasp dentures,” “thermoplastic resin,” “flexible resin removable partial denture,” “polyamide,” and “nylon” in databases PubMed/Medline, Lilacs, SciELO, and textbooks between 1955 and 2020. Theses and texts without reliable sources of publication were excluded. Once the analysis instruments were determined, the data were analyzed and discussed. NMCDs present high flexibility, easy adaptation to the abutments, color compatibility and biocompatibility with the oral mucosa, and absence of visible metal clasps. However, they need laboratory relining, grinding, and polishing, do not have criteria for its planning, become rougher and stained over time, and are able to traumatize supporting tissues. The association with metal components seems to be an alternative to increase the success of NMCDs by combining esthetics and biomechanical principles of conventional removable partial dentures. The lack of long-term clinical studies makes the professionals to rely solely on previous experiences or on the manufacturers' recommendations. It suggested that NMCDs must be indicated with caution when not used temporarily.