Obturator Manufacturing for Oronasal Fistula after Cleft Palate Repair: A Review from Handicraft to the Application of Digital Techniques

Abstract

An oronasal fistula (ONF) is an abnormal structure between the oral and nasal cavities, which is a common complication of cleft palate repair due to the failure of wound healing. When some patients with ONF are unsuitable for secondary surgical repair, the obturator treatment becomes a potential method. The objectives of the obturator treatment should be summarized as filling the ONF comfortably and cosmetically restoring the dentition with partial function. The anatomy of patients with cleft palate is complex, which may lead to a more complex structure of the ONF. Thus, the manufacturing process of the obturator for these patients is more difficult. For performing the design and fabrication process rapidly and precisely, digital techniques can help, but limitations still exist. In this review, literature searches were conducted through Medline via PubMed, Wiley Online Library, Science Direct, and Web of Science, and 122 articles were selected. The purpose of this review was to introduce the development of the obturator for treating patients with ONF after cleft palate repair, from the initial achievement of the obstruction of the ONF to later problems such as fixation, velopharyngeal insufficiency, and infection, as well as the application of digital technologies in obturator manufacturing.

Keywords: 3D printing; additive manufacturing; oronasal fistula; palatoplasty.

Figure 1

The original oronasal fistula obturator model [34]. The original oronasal fistula obturator was fabricated from hard and soft acrylics. Soft acrylic was applied on the nasal side, while self-curing hard acrylic was used to cover the soft acrylic.

Figure 2

The “U”-shaped spring oronasal fistula obturator model [36]. The central part was made of silicone, and a spring was used to adjust the retention of the obstruction according to the size of the oronasal fistula.

Figure 3

Two-piece oronasal fistula obturator with silicone bulb [41]. The silicone cap was placed over the maxillary defect, and the other part was inserted into the silicone cap.

Figure 4

Two-piece oronasal fistula obturator model with embedded magnets [41]. The two parts of the obturator were joined together by magnets.

Figure 5

Two-piece oronasal fistula obturator model with indenters [41]. The two parts of the obturator were combined via a plug and a hole corresponding to one another.

Figure 6

Hollow obturator model [53]. The obturator was designed to be hollow to reduce its weight and provide good retention.

Figure 7

Speech bulb obturator model [67]. The obturator consisted of an acrylic front part with a fixed clip, a pharyngeal bulb, and a middle part connecting these two parts. The speech bulb improved speech resonance.

Figure 8

The process of manufacturing a digital ONF obturator [21] The whole process consists of four steps: bridge creation (a–c), fixed-surface smoothing (d–f), obturator design and smoothing (g–i), and hollow and separation (j–l).