Partial Removable Dental Prosthesis Research Articles

Implant retention and support for distal extension partial removable dental prostheses: Satisfaction outcomes

The rotational movements of the distal extension denture base of partial removable dental prostheses frequently harm the prosthesis stability, leading to discomfort during function. This study evaluated the use of distal implants to retain and support partial removable dental prostheses and assessed the outcomes with respect to specific aspects of patient satisfaction. Twelve participants (mean age, 62.6 ± 7.8 years) received new conventional mandibular partial removable dental prostheses and complete maxillary dentures. After 2 months of conventional prosthesis use, the participants completed a questionnaire assessing their satisfaction. Implants were then inserted bilaterally in the mandibular posterior region and, after 4 months, ball attachments were placed on the implants and on the partial removable dental prosthesis acrylic resin base. The implants and remaining teeth were followed up with clinical and image examinations. After 2 months, satisfaction was reevaluated, and the data were analyzed by the paired Student t test and the Bonferroni correction (α=.05). Clinical evaluation found stable periodontal conditions around the implants, no intrusions or mobility of teeth, and no radiographic changes in bone level. Participants reported significant improvements (P<.05) in retention, comfort, masticatory capacity, and speaking ability after implant placement. Implant-retained and -supported removable prostheses improve retention and stability, minimize rotational movements, and significantly increase participant satisfaction.

General population norms of the Swedish short forms of Oral Health Impact Profile

We reported the development and psychometric evaluation of a Swedish 14-item and a five-item short form of the Oral Health Impact Profile. The 14-item version was derived from the English-language short form developed by Slade in1997. The five-item version was derived from the German-language short form developed by John et al. in 2006. Validity, reliability and normative values for the two short form summary scores were determined in a random sample of the adult Swedish population (response rate: 46%, N = 1366 subjects). Subjects with sufficient OHRQoL information to calculate a summary score (N = 1309) were on average 50·1 ± 17.4 years old, and 54% were women. Short form summary scores correlated highly with the 49-item OHIP-S (r ≥ 0.97 for OHIP-S14, r ≥ 0.92 for OHIP-S5) and with self-report of oral health (r ≥ 0.41). Reliability, measured with Cronbach's alpha (0.91 for OHIP-S14, 0.77 for OHIP-S5), was sufficient. In the general population, 50% of the subjects had ≥2 OHIP-S14 score points and 10% had ≥11 points, respectively. Among subjects with their own teeth only and/or fixed dental prostheses and with partial removable dental prostheses, 50% of the population had ≥2 OHIP-S14 score points, and 10% had ≥11 points. For subjects with complete dentures, the corresponding figures were 3 and 24 points. OHIP-S5 medians for subjects in the three population groups were 1, 1 and 2 points. Swedish 14-item and 5-item short forms of the OHIP have sufficient psychometric properties and provide a detailed overview about impaired OHRQoL in Sweden. The norms will serve as reference values for future studies.

Effects of clasp retention forces and abrasion on different cast crowns

Dental alloys have different mechanical properties compared with enamel. However, few studies have been conducted to determine the effects of the retention forces of clasps when applied on different cast crowns. The purpose of this study was to evaluate the retention forces of cast circumferential clasps made of cobalt-chromium alloy on complete cast crowns made of cobalt-chromium (CC group) and gold-silver-palladium (AC group) alloys, and to observe their abrasion patterns. Two groups of specimens were fabricated (n=5) and subjected to repeated insertion-removal tests (100 to 15,000 cycles). The mean values of removal forces at 100, 400, 800, 1500, 4500, 7500, 10,000, and 15,000 cycles, and their corresponding change rates compared with the initial 100 cycles' retention were determined. The differences between the 2 groups were analyzed by 2-way repeated measures analysis of variance at 100, 7500, and 15,000 cycles. The surfaces of specimens were observed with scanning electron microscopy. There were significant differences between the CC and AC groups in retention forces (P<.05). Clasp retention showed a descending trend for cobalt-chromium alloy crowns from the initial value, which decreased by 29.9% after 15,000 insertion-removal cycles. A sharp increase in retention could be observed in the AC group, which rose by 99.7% ultimately. The worn surfaces of the gold-silver-palladium crowns showed different wear patterns compared with the cobalt-chromium alloy crowns. The results indicate that cobalt-chromium alloy crowns and gold-silver-palladium alloy crowns perform differently when cobalt-chromium alloy clasps are designed as retainers for partial removable dental prostheses. Crown designs should be changed, depending on the retainer and clasp materials for partial removable dental prostheses abutment teeth.

Claspless denture design using milled abutment surfaces as precision attachment

This case report describes the combined use of fixed partial denture prosthesis (FPD) and removable partial denture (RPD) prosthesis for a patient with partially edentulous arches and few remaining teeth. The RPD was designed such that it would take advantage of benefits from milled palatal surfaces of the FPD to enhance stability and retention of the RPD and allow maitainance of oral hygiene.

Esthetic Cast Direct Retainers for Distal Extension Removable Partial Dentures

Extra coronal cast direct retainers are an essential component of cast removable partial denture prosthesis. The conventional cast circumferential clasp or the bar clasp appear unaesthetic due to visible metal display when used in the smile zone. This article describes two hidden clasp designs as an alternative to the conventional extra coronal cast direct retainer assembly for the distal extension partially edentulous situation. The same is highlighted via two case reports.

Interdisciplinary management of an adult patient with a class III malocclusion

The coexistence of a skeletal class III deformity and partial edentulism poses a clinical challenge and requires a comprehensive evaluation followed by a multidisciplinary approach. This clinical report presents the integrated management of a class III malocclusion in a 50-year-old woman with partial edentulism. The patient received adjunctive orthodontic treatment with a rigid temporary anchorage device, a Le Fort I maxillary osteotomy, and prosthodontic rehabilitation with removable maxillary copings, an overdenture, and a mandibular partial removable dental prosthesis with precision attachments.

Surface roughness and internal porosity of partial removable dental prosthesis frameworks fabricated from conventional wax and light-polymerized patterns: A comparative study

Surface roughness and internal porosity are 2 potential risk factors that threaten the biocompatibility and long-term mechanical stability of cast partial removable dental prostheses frameworks. The purpose of this study was to investigate the influence of the material, of conventional wax patterns, and the recently introduced light-polymerized patterns on the initial surface roughness and internal porosity of the cobalt-chromium castings of partial removable dental prostheses. Twenty-eight identical partial removable dental prosthesis frameworks were fabricated on a cast of a maxillary Kennedy Class III modification 1 partially edentulous patient. Fourteen frameworks were fabricated from each pattern material. The initial surface roughness, Ra (μm), of the resultant castings was measured with a profilometer. Radiographs of the castings were made on dental occlusal films with a dental x-ray unit with the following exposure conditions: tube voltage 70 kV; exposure time 1.0 seconds; tube current 7 mA; and source-film distance 35 cm. The number and size of porosities in the 3 main components (clasp units, major connectors, denture base meshwork) were assessed. Statistical analysis was conducted with the independent sample t test for surface roughness and the Mann Whitney test for internal porosity (α=.05). The statistical analysis of mean surface roughness and internal porosity revealed no significant difference between the 2 groups. The surface roughness and internal porosity of frameworks fabricated from conventional wax and Liwa patterns were comparable, with no significant differences between the 2 pattern materials.

Cost‐effectiveness of tooth replacement strategies for partially dentate elderly: a randomized controlled clinical trial

To conduct a cost-effectiveness analysis comparing two different tooth replacement strategies for partially dentate older patients, namely partial removable dental prostheses (RDP) and functionally orientated treatment based on the shortened dental arch concept (SDA). Ninety-two partially dentate older patients completed a randomized controlled clinical trial. Patients were randomly allocated to two treatment groups: the RDP group and the SDA group. Treatment effect was measured using impact on oral health-related quality of life (OHrQOL), and the costs involved in providing and maintaining care were recorded for all patients. Patients were followed for 12 months after treatment intervention. All treatment was provided by a single operator. The total cost of achieving the minimally important clinical difference (MID) in OHrQOL for an average patient in the RDP group was €464.64. For the SDA group, the cost of achieving the MID for an average patient was €252.00. The cost-effectiveness ratio was therefore 1:1.84 in favour of SDA treatment. With an increasingly ageing population, many patients will continue to benefit from removable prostheses to replace their missing natural teeth. From a purely economic standpoint, the results from this analysis suggest that the treatment of partially dentate older adults should be focused on functionally orientated treatment because it is simply more cost-effective.

Prosthodontic rehabilitation of a patient diagnosed with multiple idiopathic root resorption

A female college student was referred by her general dentist for evaluation of the interproximal caries-like lesions discovered during her biannual visit. The lesions were determined to result from external resorption of unknown origin. After the most affected teeth had been extracted and the other teeth were restored after periodontal surgery, an interim partial removable dental prosthesis was placed. Two months later, the resorption pattern had proliferated to the rest of her dentition, thus revising the treatment plan to involve full mouth extractions and to place immediate maxillary and mandibular complete removable dental prostheses. Subsequently, 6 titanium dental implants were placed in each arch, and, after healing, opposing metal ceramic screw-retained fixed dental prostheses were inserted.

A technique to restore worn denture teeth on a partial removable dental prosthesis by using ceramic onlays with CAD/CAM technology

High wear resistance of denture teeth on a removable prosthesis contributes substantially to the clinical longevity of the prosthesis. In the restoration of worn denture teeth on a partial removable dental prosthesis (PRDP), acrylic resin denture teeth replacement can be considered if the opposing occlusal surfaces are acrylic, which shows similar wear rates. However, when the antagonistic materials are enamel or ceramic, an alternative material with better wear resistance is recommended for the maintenance of vertical dimension of occlusion over time.

A magnetic device for recording and reproducing the path of placement for partial removable dental prostheses

Accurate planning for the framework design of a partial removable dental prosthesis (PRDP) requires careful analysis of the diagnostic cast with a dental surveyor to determine the optimal path of placement.1 The selected path of placement should be recorded as a reference for subsequent steps to reposition the cast with the same recorded tilt.1–3 The following procedure uses a magnetic device to record and reproduce the path of placement of an PRDP.

Impact of removable partial denture prosthesis on chewing efficiency

Removable partial denture prostheses are still being used for anatomic, medical and economic reasons. However, the impact on chewing parameters is poorly described.ObjectivesThe objective of this study was to estimate the impact of removable partial denture prosthesis on masticatory parameters.Material and MethodsNineteen removable partial denture prosthesis (RPDP) wearers participated in the study. Among them, 10 subjects were Kennedy Class III partially edentulous and 9 with posterior edentulism (Class I). All presented a complete and full dentate opposing arch. The subjects chewed samples of carrots and peanuts with and without their prosthesis. The granulometry of the expectorated boluses from carrot and peanuts was characterized by median particle size (D50), determined at the natural point of swallowing. Number of chewing cycles (CC), chewing time (CT) and chewing frequency (CF=CC/CT) were video recorded.ResultsWith RPDP, the mean D50 values for carrot and peanuts were lower [Repeated Model Procedures (RMP), F=15, p<0.001] regardless of the type of Kennedy Class. For each food, mean CC, CT and CF values recorded decreased (RMP, F=18, F=9, and F=20 respectively, p<0.01). With or without RPD, the boluses' granulometry values were above the masticatory normative index (MNI) determined as 4,000 µm.ConclusionRPDP rehabilitation improves the ability to reduce the bolus particle size, but does not reestablish fully the masticatory function.Clinical relevanceThis study encourages the clinical improvement of oral rehabilitation procedure.

A two-step (altered cast) impression technique in the prosthetic rehabilitation of a patient after a maxillectomy: A clinical report

This clinical report describes the prosthetic rehabilitation complicated by trismus (as a consequence of surgery and radiation therapy) of a patient with an acquired maxillary defect, after surgical removal of the right maxillary sinus tumor. The patient was restored with a partial removable dental prosthesis with a hollow bulb obturator to obtain orofacial rehabilitation and defect obturation. Precise obturation requires an accurate impression of the resection defect. A 2-step impression was performed because of trismus. A primary maxillary impression was made with an irreversible hydrocolloid, while a secondary (altered cast) impression was made with a silicone material by using the obturator cast framework as a tray. In that way an altered cast was produced. Subsequently, an obturator prosthesis was processed with a conventional technique.

Modern application of the Skinner vertical movement stress director for distal extension partial removable dental prostheses: A clinical report

This article describes the prosthetic rehabilitation of a partially edentulous patient with a partial removable dental prosthesis (PRDP) designed to dissipate stress transmission to the denture foundation and abutment teeth. The Skinner stress director is considered an alternative design for managing partially edentulous patients.

The randomized shortened dental arch study: oral health-related quality of life

Although the shortened dental arch (SDA) concept is a widely accepted strategy to avoid overtreatment, little is known on its impact on oral health-related quality of life (OHRQoL). This multicenter randomized controlled trial aimed to investigate the OHRQoL for removable partial dental prostheses (RPDP) with molar replacement versus the SDA concept. In both groups, missing anterior teeth were replaced with fixed dental prosthesis. Two hundred fifteen patients with bilateral molar loss in at least one jaw were included. The Oral Health Impact Profile (OHIP-49) was completed before; 6 weeks (baseline), 6 months, and 12 months after treatment; and thereafter annually until 5 years. Of the initial cohort, 81 patients were assigned to the RPDP group and 71 to the SDA group (age, 34 to 86 years). Before treatment, the median OHIP score was similar in both groups (RPDP, 38.0; SDA, 40.0; n.s.). Results indicate marked improvements in OHRQoL in both groups between pretreatment and baseline (RPDP, 27.0; SDA, 19.0; p ≤ 0.0001) which continued in the RPDP group until the 1-year follow-up (p = 0.0002). These significant reductions in OHIP scores are reflected in its subscales. No further differences were seen within and between groups during the remainder observation period. Both treatments show a significant improvement in OHRQoL which continued in the RPDP group until the 1-year follow-up. No significant differences were seen between groups. For improving OHRQoL, it is not necessary to replace missing molars with a RPDP.

The combination of a nylon and traditional partial removable dental prosthesis for improved esthetics: A clinical report

A benefit of a nylon partial removable dental prosthesis (PRDP) is the absence of a metal framework, providing improved esthetics. Unfortunately, the lack of a traditional framework reduces rigidity and the support of occlusal rests. This clinical report describes a combination of a nylon PRDP (polyamide denture base resin) and a traditional PRDP (framework/resin) for a Kennedy Class II, Modification 1, partially edentulous mandible.

インプラント除去後に可撤性部分床義歯を用いて補綴した症例

インプラント除去後に可撤性部分床義歯を用いて補綴した症例

Implant placement under existing removable dental prostheses and its effect on oral health‐related quality of life

One aim of this prospective clinical study was to measure the effects of strategicimplant placement under removable partial dental prostheses (RPDPs) and among removable complete dental prostheses (RCDPs) on oral health-related quality of life (OHRQoL). Twenty-three patients participated in this study restored with RCDPs (n = 12) or RPDPs retained by telescopic crowns with 1-2 abutment teeth (n = 11). The total number of abutments was increased to 5-6 (maxilla) or to 4 (mandible) by placing implants in strategically advantageous regions. Ball attachments were attached to the implants and integrated in the existing denture. The Oral Health Impact Profile (49 questions) was completed by patients before implant placement, at baseline (integration of ball attachments), and during 12- and 24-month follow-up visits. There were marked reductions of impacts in both groups when comparing pre-treatment scores and scores at baseline (P < 0.0001), 12-month (P < 0.0001), and 24-month follow-up visits (P < 0.0001), respectively. For none of the visits, a significant difference between the two groups was detected (P > 0.05). It can be concluded that a strategic placement of implants under the existing dental prostheses improves OHRQoL in both treatment groups.

The fabrication of a CAD/CAM ceramic crown to fit an existing partial removable dental prosthesis: A clinical report

The application of computer-aided design/computer-assisted manufacturing (CAD/CAM) technology to fabricate a retrofit ceramic surveyed crown to an existing partial removable dental prosthesis (PRDP) is described. The fabrication of a surveyed crown by using CAD/CAM technology enables precise and easy replication of the shape and contours as well as the rest seat of the existing abutment tooth, ensuring excellent adaptation to the existing PRDP framework with minimal adjustment.

The prosthetic rehabilitation of a panfacial fracture patient after reduction: A clinical report

Panfacial fractures involve trauma to the lower, middle, and upper facial bones and often require a team approach for management. Early and complete restoration of preinjury facial contours and function should be the goal of the oral and maxillofacial surgeon and the prosthodontist. When the intraoral landmarks are lost, overall facial anatomic landmarks can be used to restore the oral cavity. A patient with complex clinical panfacial fractures, including a vertically and horizontally malpositioned native alveolar bone and severe facial asymmetry, is presented. A functional and esthetic rehabilitation was successfully accomplished by using a partial removable dental prosthesis retained with telescopic crowns and magnetic attachments in the maxilla and osseointegrated implants to support a definitive dental prosthesis in the mandible.