The introduction and evolution of CAD/CAM technology into complete dentures fabrication brought high expectations in improving disadvantages associated with conventional methods.
The purpose of this ...review was to analyse the existing literature on computer-engineered complete dentures and to determine their advantages over the conventional dentures.
An electronic search of the English literature from January 1994 to March 2018 was performed in PubMed/MEDLINE, using the following keywords: CAD/CAM complete dentures, computer-engineered complete dentures, complete digital dentures, complete milled dentures, and rapid prototyping dentures.
A total of 179 English language titles were obtained from the database, and 14 were relevant to fulfil the purpose of this review. A review of 7 articles is summarized in 2 tables for presenting a comparison between CAD/CAM and conventional dentures in clinical and laboratory studies.
Following the review of articles that discussed the comparison between CAD/CAM and conventional complete dentures in clinical studies, it can be concluded that the main advantages of CAD/CAM dentures are the reduced clinical chair time and the number of visits, digital archiving, significantly higher retention, and more favorable clinical and patient-centered outcomes. As a result of the review of laboratory studies, superior mechanical and physical properties in CAD/CAM dentures were revealed, concerning enhanced accuracy of fit of milled denture bases, less denture tooth movement and increased toughness, ultimate flexural strength, and higher elastic modulus.
A novel technique of digitally printed custom trays assembled with occlusion rims and gothic arch tracing devices attached with tenon-and-mortise joints for biofunctional complete dentures that could ...be delivered in 2 visits is presented. This technique takes advantage of closed-mouth impressions and objective jaw relation records by following the biofunctional prosthetic system concept with high efficiency and reduced labor.
This study evaluated the reliability of a face scanner in measuring the vertical dimension of occlusion (VDO).
Fully dentate volunteers (n = 20; mean-age = 30.0 ± 10.7 years) were recruited. Clinical ...facial measurements were obtained using a digital caliper and a face scanner (Obiscanner, Fifthingenium, Italy). The scans were imported into a mesh-processing software, and the distances were measured digitally. Measurements were obtained for each participant with the jaws positioned in maximal intercuspation (MI) and with increased vertical distances of 2, 4, and 6 mm. Vertical and horizontal measures were obtained using facial anatomical landmarks: Glabella (GL), Pronasale (PrN), Subnasale (SbN), inferior border of the right and left Alare, Labiale superius (Ls), right and left Cheilion (Ch), Soft Pogonion (SPg), right and left Tragus of the ear (Tr), for all selected vertical positions. Data analysis included intra-class correlation coefficient (ICC), pairwise comparison tests, Bland-Altman plots, and Passing-Bablok regression.
120 VDO measurements (clinical=60, digital=60) were recorded by two independent evaluators. Mean differences between digital and clinical measurements ranged from 0.054 ± 0.14 mm to 0.203 ± 0.13 mm. All parameters were strongly correlated (r > 0.93; p < 0.001). ICC estimates revealed excellent reliability, and the measuring procedure yielded the same results on repeated trials irrespective of the raters and measurement methods. Bland-Altman plots revealed a difference, between digital and clinical measurements, of 1.7 % for the vertical measurements. Regression analysis revealed no significant proportional difference between the two methods, so both can be used interchangeably.
The findings of this study demonstrate that VDO can be measured accurately from face scans using 3D mesh-processing software and that even small changes in the VDO could be detected using the digital methods.
Findings provide evidence about the reliability of a digital method for jaw relation registrations and may be applied towards incorporating this method into clinical workflows for computer-aided-design/ computer-assisted-manufacturing (CAD-CAM) dentures.
Introduction. Many alternatives exist for treating total edentulism, including conventional complete dentures (CCD), implant-supported overdentures, and implant-supported fixed prostheses. Complete ...dentures have been the standard prosthodontic therapy for people who are edentulous for quite some time. The majority of denture-wearing edentulous patients are pleased with their prostheses, but some people just can’t get used to them, and it seems that the level of clinical and technical expertise involved or the quality of the tissues supporting the dentures have little effect on how happy those people are with their results. While the routine prescription of an overdenture supported by two or even one implant for an edentulous mandible is becoming the standard of care in many developed nations, this treatment option is out of reach for the majority of the world’s poor, who often cannot afford even “low-tech” therapies like conventional dentures.
AIMTo compare and evaluate the mean bite force and masticatory performance of conventional complete dentures (CD) in comparison with the lower implant-supported overdenture opposing an upper CD by ...using a strain gauge transducer and a test material respectively, in the same patient over a different period of time. MATERIALS AND METHODSThe study included 20 edentulous patients in the age range 45-65 years with a good general and oral health. In the first phase of the study, conventional CD were fabricated and delivered to each patient who participated in the study. A strain gauge transducer was used to analyze the maximum bite force and an agar test material was used to assess the masticatory performance using the sieve method. The existing lower denture was used to deliver a two-implant overdenture system and two implants were placed in the intermental-foraminal region of the mandible. One month after the delivery of implant-supported overdenture, the maximum bite force and masticatory performance were assessed as before. RESULTSTo test two independent variables, the data were analyzed statistically using an unpaired t-test. In comparison to the conventional upper and lower CD rehabilitations, the implant-supported lower denture and conventional upper CD rehabilitations resulted in statistically significant improvements in biting force and masticatory performance. CONCLUSIONStudy findings demonstrate that the completely edentulous patients can be rehabilitated with the upper CD and lower two-implant supported overdenture system that offers improved biting force and masticatory performance than conventional upper and lower dentures. CLINICAL SIGNIFICANCEMasticatory efficiency is one of the important indicators of functional state of stomatognathic system. Determination of individual masticatory performance has been used to ascertain the therapeutic effect of prosthetic device.
Background: The scientific interest in dominant Candida species colonizing the surface of conventional and double-layer dentures (D-LCDs) is still topical. Numerous studies are comparing fungal ...colonization in both types of removable dentures. Aim: Performing a comparative analysis of the colonization of Candida spp. on the dentures surfaces of the conventional (CCDs) and the double-layer dentures (soft-lined) complete dentures (D-LCDs) over six months, placing them under the same intraoral in vivo conditions. Methods: For isolating Candida spp., specimens were obtained from inner denture surfaces using two sterile swabs, one for the upper complete denture (n=28) and one for the lower complete denture (n=28). The culture-based Candida detection method with CHROM agar was used to identify Candida species. Results: In the third month after dentures delivery C. Albicans is the predominant Candida spp. found on both types of complete dentures surface and isolated in 46 % of the patients with conventional complete dentures and 43 % with double-layer dentures (p>0.05). In the sixth month of the finished prosthetic treatment, combinations of C. Albicans and non-albicans Candida, predominantly C. Tropicalis, C. Glabrata and C. Parapsilosis, were found in 43 % of D-LCDs and 45 % of CCDs (p>0.05). Conclusion: There was no difference in colonization based on the different materials used for denture fabrication. However, there is a significant proportional change for all studied Candida spp. over the period (3-6 months after delivery), irrespective of the denture material used.
Purpose
To evaluate the color stability of CAD/CAM complete denture resins.
Materials and Methods
A total of 176 resin specimens were manufactured from conventional heat‐polymerizing (pink: CONHCP: n ...= 16; tooth‐shade: CONHCT: n = 16), CAD/CAM subtractively manufactured (pink: WIMP: n = 16, AVMP: n = 16, MEMP: n = 16, POMP: n = 16; tooth‐shade: AVMT: n = 16, MEMT: n = 16, POMT: n = 16), and additively manufactured (pink: NDRPP: n = 16; tooth‐shade: NDRPT: n = 16) denture resins; four different aging processes (thermal cycling, distilled water, red‐wine, and coffee) were used. A spectrophotometer evaluated the color change (ΔE) using two modes of measurements (specular component included (ΔESCI) and specular component excluded (ΔESCE)) recorded at baseline (T0) and at day#30 (T30). ANOVA and post hoc tests were used for statistical analysis (alpha = 0.05).
Results
Additively manufactured resins (NDRPP and NDRPT) demonstrated significant ΔE in comparison to the other groups in all aging media (p < 0.001). WIMP demonstrated higher ΔESCI in comparison to the other subtractively manufactured groups in distilled water (p < 0.001). In red‐wine, AVMT revealed significantly more ΔESCE than POMT (p = 0.039). In coffee, the ΔESCE was higher for CONHCT than MEMT (p = 0.026) and POMT (p = 0.011). Similarly, in coffee the ΔESCE for AVMT was higher than POMT (p = 0.030).
Conclusion
Additively manufactured denture resins demonstrated the maximum color change compared to conventional heat‐polymerized and CAD/CAM subtractively manufactured denture resins. Furthermore, CAD/CAM subtractively manufactured denture resins were not inferior to conventional resins in terms of color stability.
PDF
