Does a face-bow lead to better occlusion in complete dentures? A randomized controlled trial: part I

Sagittal condylar guidance angle measurement methods: A systematic review

STATEMENT OF PROBLEM

Precise assessment of the condylar guidance angle can aid successful prosthodontic treatment. However, the reliability and accuracy of current methods remain unclear.

PURPOSE

The purpose of this systematic review was to evaluate the reliability and accuracy of current methods of determining the sagittal condylar guidance angle, including protrusive interocclusal records, axiography, cone beam computed tomography (CBCT), and panoramic and cephalometric radiographs.

MATERIAL AND METHODS

A literature search was conducted using BASE, Embase, PubMed, and Web of Science databases up to June 2022. Inclusion criteria involved studies that compared protrusive interocclusal records against other methods of sagittal condylar guidance angle assessment in adult dentate and edentulous patients. Studies that did not provide the values for the right and left joint separately were excluded. The methodological quality of the included studies was assessed by using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Data were tabulated and analyzed for correlations and their significance.

RESULTS

A total of 24 articles qualified for the analysis. The differences between protrusive interocclusal records and panoramic radiograph sagittal condylar guidance angle values were up to 9 degrees. Lateral cephalometric radiographs revealed greater condylar guidance values than facebow transfers or the Bonwill methods. Correlations between average sagittal condylar guidance angle values obtained from CBCT and protrusive interocclusal records differed depending on the method of registration. For protrusive interocclusal records, axiographic or pantographic measurement variance analysis showed that the condylar inclination values recorded with wax were statistically lower than those recorded with a pantograph (P<.05).

CONCLUSIONS

Although CBCT appears to be the most suitable method of evaluating the sagittal condylar guidance angle, the limitations and discrepancies among methods, including protrusive interocclusal records and panoramic and cephalometric radiographs, should be acknowledged. Digital axiography, with its potential to capture comprehensive functional data, may surpass other techniques. The use of mean values for articulators may be a practical solution for some patients. Further research is needed to refine sagittal condylar guidance angle assessment methods and to develop more reproducible and reliable approaches for the future.

Occlusal adjustment of 3-unit tooth-supported fixed dental prostheses fabricated with complete-digital and -analog workflows: A crossover clinical trial

AIM

This prospective crossover clinical trial aimed to compare the complete-digital and -analog workflows in terms of occlusal adjustment of 3-unit tooth-supported fixed dental prostheses, operator, and patient preferences.

MATERIALS AND METHOD

This study included twelve patients receiving fourteen 3-unit posterior FDPs. 2 FDPs were made for each restoration site: one fabricated in complete-digital workflow comprising intraoral scan with static bite registration (Trios 3) and a monolithic zirconia FDP (test); the other fabricated in complete-analog workflow comprising conventional impression/face-bow transfer and a porcelain-fused-to-metal FDP (control). The FDPs (n=28) were intraorally/provisionally fixed, and quadrant-like intraoral scans were taken for every FDP before & after their occlusal adjustments. Pre- and post-adjustment scans of each FDP were then superimposed using best-fit alignment (GOM Inspect) to measure the volumetric occlusal adjustment amount (mm³) (3Matic) (Mann Whitney U, α=0.05). The patient and operator experience for digital and analog workflows were evaluated using visual analog scales (Wilcoxon test, α=0.05).

RESULTS

Mean occlusal adjustments were 7.63 mm³ [±7.02] and 25.95 mm³ [±39.61] for test and control groups, respectively. The volumetric adjustment difference was clinically noticeable but not significant (P=0.12). The impression and digital workflow adjustment were perceived more favorably by both operator (P=0.003, P=0.046, respectively) and the patients (P=0.003, P=0.002, respectively).

CONCLUSIONS

Within the limitations of this clinical study, the complete digital workflow with digital static bite-registration provided high occlusal accuracy for short-span tooth-supported FDPs. In addition, the patient and operator preferences significantly favored the digital workflow.

CLINICAL SIGNIFICANCE

Complete-digital workflow employing intraoral scanning and model-free fabrication of monolithic-Zr short-span tooth-supported FDPs offers an effective treatment modality with sufficient occlusal accuracy. Therefore complete-digital workflow is a valid alternative for complete-analog workflow comprising conventional impression, face-bow transfer, and use of a semi-adjustable articulator.

Use of Facebow device in prosthodontics: A systematic review on randomized control trials

Aim

Recording the maxillomandibular relationship is important in various prosthodontic treatments. Evidence of face-bow transfer resulting in improved outcome is conflicting. Hence the objective of this study is to determine the use of face-bow transfer in prosthodontics.

Settings and Design

: Systematic review based on PRISMA guidelines.">.

Materials and Methods

A protocol was developed prior, which covered all aspects of the review. The databases explored were MEDLINE database, ScienceDirect, and Cochrane collaboration library. The PICO model included participants who received a complete denture/partial denture prosthesis. Intervention was the use of the face-bow device. Comparator was prosthesis made with a simple procedure of not using a face-bow device for prosthodontic rehabilitation. Outcomes were patient satisfaction with dentures, the stability of the dentures, esthetics, and time taken for clinical and laboratory procedures. Only randomized clinical trials were included in this study. The methodological quality of the studies was assessed according to the Cochrane risk of bias tool.

Statistical Analysis Used

Qualitative analysis.

Results

A total of 144 articles were identified. On excluding 4 duplicates and screening the title and abstracts of the rest of the records based on exclusion criteria only 15 studies were selected for review.

Conclusions

The use of the face-bow did not yield superior results for the quality of the prosthesis. Therefore, there is no evidence for the utility of face-bow transfer in complete denture treatment. However, no inference could be drawn for its utility in partial denture prosthodontics as there was no study to draw an inference.

Masticatory performance of different impression methods for complete denture fabrication: A randomized controlled trial

OBJECTIVES

To compare the effect of conventional complete dentures fabricated using two different impression methods on masticatory performance and factors relating to masticatory performance in a randomized controlled trial.

METHODS

A crossover randomized controlled trial was performed with edentulous patients requiring maxillomandibular complete dentures. Mandibular complete dentures were fabricated using two different methods. The conventional method (C) used a custom tray border molded with an impression compound and a silicone. The simplified method (S) used a stock tray and an alginate. Participants were randomly divided into the two groups. In the C-S group, the conventional method was used first, followed by the simplified method; the order was reversed in the SC group. Adjustments were performed four times. The wash out period was 1 month. Masticatory performance as assessed by the mixing of a color-changeable chewing gum (mixing ability). Maximum occlusal force, occlusal contact area, and perceived chewing ability were assessed for each group.

RESULTS

Twenty-seven patients underwent randomization and 24 participants completed the trial. With regard to occlusal contact area, the conventional method showed significantly larger occlusal contact area than the simplified method. No significant differences were observed between the two methods regarding mixing ability, maximum occlusal force, and perceived chewing ability.

CONCLUSIONS

This study showed that complete dentures fabricated with the conventional method had a significantly larger occlusal contact area than those made using the simplified method.

CLINICAL SIGNIFICANCE

Complete dentures fabricated with the conventional method, comprising a preliminary impression using alginate in a stock tray followed by a final impression using silicone impression material in a border molded custom tray, resulted in fewer post-insertion adjustments than the simplified method, potentially contributing to earlier stability of new dentures.

Utility of facebow in the fabrication of complete dentures, occlusal splints and full arch fixed dental prostheses: A systematic review

OBJECTIVE

The objective of this study is to assess the utility of facebow transfer in the fabrication of occlusal splints, complete dentures and full arch fixed dental prosthesis.

MATERIALS AND METHODS

A systematic review protocol was registered at PROSPERO registry, University of York, UK (CRD42016041919). Following databases were explored: PubMed, CINAHL, Cochrane, and Web of knowledge. The PICO model included participants who received occlusal splint or complete denture or full arch fixed dental prosthesis at the centric relation position. The intervention was the use of facebow transfer. Comparators were prosthesis made without using a facebow. Outcomes were the patient satisfaction of the prosthesis and the need for laboratory adjustments. Only randomized clinical trials were included in the present review. A customized data extraction pro forma was used to extract the data and assess its quality.

RESULTS

A total of 505 articles were retrieved. On excluding duplicates, protocols, case reports, case series, narrative reviews, etc., only eight studies were selected for review. Six clinical trials on 249 complete dentures and two clinical trials on 65 occlusal splints were reviewed. No study on full arch crown and bridge work satisfied the inclusion criteria.

CONCLUSIONS

The use of facebow did not yield a superior fit or comfort of the complete dentures or occlusal splints. Therefore, there is no evidence of the utility facebow transfer for these prostheses. However, no inference could be drawn for its utility in full arch fixed dental prosthesis as there were no studies to draw an inference.