Is It Cost Effective to Add an Intraoral Scanner to an Oral and Maxillofacial Surgery Practice?

PURPOSE: Intraoral scanners (IOSs), which create digital "impressions" of dental arches, have become popular for prosthetic and orthodontic applications. Adoption in oral and maxillofacial surgery (OMS) practices has been slower, likely because of high implementation costs and low-volume use. The purpose of this study was to evaluate costs for introduction of an IOS into an OMS practice. The authors hypothesized that digital impressions would be more efficient in time and cost compared with conventional impressions and that implementation costs would be offset within 1 year. MATERIALS AND METHODS: This was a prospective study that included patients who had digital impressions during the first year after introduction of an IOS to the practice. Conventional alginate impressions obtained at the same visit were included for comparison. Variables included time for each step in each impression process, IOS experience of the operator obtaining the impression, and associated costs. Per-arch costs for each technique were calculated using time-driven activity-based costing methodology. RESULTS: Sixty-three digital impressions and 31 conventional impressions were included. Mean total times for digital and conventional impressions were 14.1 ± 1.3 and 19.4 ± 4.0 minutes per arch, respectively. On a per-patient basis (2 arches for digital impressions and 4 arches for conventional impressions because of the inability to create duplicate stone models from each alginate impression), total impression times were 24.8 ± 2.7 minutes for digital and 67.2 ± 14.8 minutes for conventional impressions. Total calculated costs for digital and conventional impressions were $21.42 and $29.40 per arch and $37.66 and $102.10 per patient, respectively. In a practice with 2 patients for impressions per working day (500 per year), it would take 1.04 years to offset the purchase of the IOS; with 5 sets of impressions per day (1,250 per year), it would take 5 months. CONCLUSION: Digital impressions are more efficient and cost effective than standard impressions, and implementation costs can be offset within the first year.

Randomised clinical trial of patient satisfaction with traditional and simplified complete dentures.

To clinically evaluate the patient satisfaction and associated costs of dentures made using a simplified procedure that eliminates assembly on the articulator and dentures made with the conventional technique. Single-blind randomised clinical trial. Forty edentulous patients were randomly divided into 2 groups. One group received dentures made using the conventional method (CG), and the other using a simplified technique (SG) that omits the use of functional impressions (with modelling compound and ZOE impression paste) and an articulator to assemble the models. Overall patient satisfaction was assessed at 3 and 6 months by means of a Numerical Rating Scale (NRS). The comparisons were made using a repeated measures ANOVA (P = .05). No significant differences were found in terms of the satisfaction stated by the patients or the quality of the prosthesis evaluated by a professional among the dentures made using the traditional (n = 17) and simplified (n = 21) techniques. The rehabilitation of an edentulous patient with a simplified technique for the preparation of a total prosthesis is a feasible, more economical alternative and accepted by most patients.

Cost-effectiveness analysis of two impression methods for the fabrication of mandibular complete dentures.

OBJECTIVES: To compare the cost and to evaluate cost-effectiveness of fabricating mandibular complete dentures (CDs) using two different impression methods. METHODS: A crossover randomized controlled trial including 27 edentulous participants was performed. Mandibular CDs were fabricated using two different impression methods, as follows: (i) conventional method using a custom tray border moulded with impression compound and silicone and (ii) simplified method using a stock tray and alginate. Cost analysis was performed from a clinical practitioner's perspective. The total cost included labor cost, which was calculated using the time spent by dentists and technicians in fabricating CDs and their hourly wages, and the material costs, which were calculated using purchase prices. To evaluate cost-effectiveness, we used general patient satisfaction as an indicator of effectiveness and calculated the incremental cost effectiveness ratio (ICER). ICER represents the cost per one unit of effectiveness. RESULTS: The trial was completed by 24 participants. The total cost was 43,904 Japanese Yen (JPY) (330.91 EUR / 395.78 USD) for the conventional method and 39,792 JPY (299.93 EUR / 358.70 USD) for the simplified method, and this difference was statistically significant (p<0.001). The ICER showed a cost of 633 JPY (4.77 EUR / 5.70 USD) for every one point change in general patient satisfaction. CONCLUSIONS: The results indicated that the total cost of the conventional method was significantly higher than that of the simplified method (p<0.001). CLINICAL SIGNIFICANCE: The conventional impression method for fabricating mandibular CDs, which took additional 633 JPY (4.77 EUR / 5.70 USD) for improvement of general satisfaction, is supposed to be clinically meaningful1.

[Evaluation of production and clinical working time of computer-aided design/computer-aided manufacturing (CAD/CAM) custom trays for complete denture].

OBJECTIVE: To compare the technician fabrication time and clinical working time of custom trays fabricated using two different methods, the three-dimensional printing custom trays and the conventional custom trays, and to prove the feasibility of the computer-aided design/computer-aided manufacturing (CAD/CAM) custom trays in clinical use from the perspective of clinical time cost. METHODS: Twenty edentulous patients were recruited into this study, which was prospective, single blind, randomized self-control clinical trials. Two custom trays were fabricated for each participant. One of the custom trays was fabricated using functional suitable denture (FSD) system through CAD/CAM process, and the other was manually fabricated using conventional methods. Then the final impressions were taken using both the custom trays, followed by utilizing the final impression to fabricate complete dentures respectively. The technician production time of the custom trays and the clinical working time of taking the final impression was recorded. RESULTS: The average time spent on fabricating the three-dimensional printing custom trays using FSD system and fabricating the conventional custom trays manually were (28.6±2.9) min and (31.1±5.7) min, respectively. The average time spent on making the final impression with the three-dimensional printing custom trays using FSD system and the conventional custom trays fabricated manually were (23.4±11.5) min and (25.4±13.0) min, respectively. There was significant difference in the technician fabrication time and the clinical working time between the three-dimensional printing custom trays using FSD system and the conventional custom trays fabricated manually (P<0.05). CONCLUSION: The average time spent on fabricating three-dimensional printing custom trays using FSD system and making the final impression with the trays are less than those of the conventional custom trays fabricated manually, which reveals that the FSD three-dimensional printing custom trays is less time-consuming both in the clinical and laboratory process than the conventional custom trays. In addition, when we manufacture custom trays by three-dimensional printing method, there is no need to pour preliminary cast after taking the primary impression, therefore, it can save the impression material and model material. As to completing denture restoration, manufacturing custom trays using FSD system is worth being popularized.

Digitizing the Facebow: A Clinician/Technician Communication Tool.

Communication between the clinician and the technician has been an ongoing problem in dentistry. To improve the issue, a dental software application has been developed--the Virtual Facebow App. It is an alternative to the traditional analog facebow, used to orient the maxillary cast in mounting. Comparison data of the two methods indicated that the digitized virtual facebow provided increased efficiency in mounting, increased accuracy in occlusion, and lower cost. Occlusal accuracy, lab time, and total time were statistically significant (P<.05). The virtual facebow provides a novel alternative for cast mounting and another tool for clinician-technician communication.

Modified indexing technique for the immediate interim restoration of a dental implant.

Because of the functional and esthetic requirements of patients, different techniques have been proposed to reduce the time between dental implant placement and interim restoration fabrication. This article describes a modified indexing technique by using a surgical template for open-tray impression and definitive cast development during immediate loading procedures. This technique does not use a complete impression of the oral cavity and, therefore, is more comfortable, less time consuming, and less expensive. It also allows the fabrication of interim restorations with the optimal shape for developing an adequate emergence profile.

A randomized trial on simplified and conventional methods for complete denture fabrication: cost analysis.

PURPOSE: This study aimed to quantify the costs of complete denture fabrication by a simplified method compared with a conventional protocol. MATERIALS AND METHODS: A sample of edentulous patients needing conventional maxillary and mandibular complete dentures was randomly divided into group S, which received dentures fabricated by a simplified method, and group C, which received conventionally fabricated dentures. We calculated direct and indirect costs for each participant including unscheduled procedures. This study assessed 19 and 20 participants allocated into groups S and C, respectively, and comparisons between groups were conducted by the Mann-Whitney and Student's t-test (α = 0.05). RESULTS: Complete denture fabrication demanded median time periods of 173.2 and 284.5 minutes from the operator for groups S and C respectively, and 46.6 and 61.7 minutes from the dental assistant (significant differences, p < 0.05). There was no difference between groups regarding postinsertion adjustments. Group S showed lower values for costs with materials and time spent by patients than group C during the fabrication stage, but not during adjustments. CONCLUSIONS: The median direct cost of complete denture treatment was 34.9% lower for the simplified method. It can be concluded that the simplified method is less costly for patients and the health system when compared with a conventional protocol for the rehabilitation of edentulous patients.

Complete arch implant impression technique.

When making a definitive impression for an arch containing multiple implants, there are many reported techniques for splinting impression copings. This article introduces a splint technique that uses the shim method, which has been demonstrated to reduce laboratory and patient chair time, the number of impression copings and laboratory analogs needed, and the ultimate cost.

Wastage of a silicone impression material in a general practice setting: a comparison between hand and automixing methods.

A practice-based, randomised, controlled trial has been undertaken to investigate the wastage of impression material when recording full arch one-stage, polyvinyl siloxane impressions using four techniques: putty and automix light viscosity material, putty and automix regular viscosity material, putty and tubed light viscosity material, and putty and tubed regular viscosity material. A total of 100 maxillary impressions, comprising 25 recorded using each of the four techniques, were obtained according to a predetermined scheme for randomisation. All material wasted in dispensing, mixing and applying each impression was determined by repeated weighing. Statistical comparisons of the mean weights of material wasted for each type of impression revealed that significantly (P < 0.01) less wastage occurred with the automix techniques. It is concluded that automix impression techniques may, in more extensive studies, be found to be more cost effective than tubed impression material techniques when recording impressions of the type investigated.

[The reliability of class A alginate impressions]. / Fiabilité des empreintes à l'alginate de classe A.

The class A alginates present very good properties of dimensional precision and reproduction of details, comparable to those of the reversible hydrocolloïdes and certain elastomeres used for the realization of secondary prints of precision in fixed prosthesis and in removable prosthesis. Besides, their application is easier and they are costless. The valorization of these print materials could certainly contribute to reduce the cost of comes back of prostheses in countries under developed where the weak power economic populations constitute a brake to the access to cares of health. To exploit qualities of these print biomaterials well, it agrees to manage correctly the parameters of their application. To this effect, the present survey puts in evidence that the maximum delay of stream that guarantees the good dimensional stability of these class A alginates is of 45 minutes in the hot and humid climatic tropical country conditions.

A full-arch interocclusal impression tray to eliminate lack of coverage and tendency to distort.

This article discusses a metal full-arch interocclusal impression tray. It uses a separation insert that extends into a split handle. Portions of the tray may be used to record sections of an arch singly or in combination from quadrant to full arch. A combination of different materials may be used, selected for low-cost properties that work compatibly side-by-side and/or back-to-back. The tray can be modified by the addition of a mounting stud to the tray handle, which permits linking it to a face-bow to facilitate axis mounting.