PURPOSEThis in vitro study investigated and compared the durability and retention of three types of attachments.MATERIALS AND METHODSThree commercially available attachments were investigated: Clix®, Dalbo-Plus® and Locator®. In total, 72 samples of these attachments were placed in the acrylic resin forms and subjected to mechanical testing (5400 cycles of insertion and removal) over the respective ball or Locator abutments immersed in artificial saliva at pH 7 and 37℃. The abutments were placed at angulations of 0°, 10° and 20°. The retention force was recorded at the beginning and after 540, 1080, 2160, 3240, 4320 and 5400 insertion-removal cycles.RESULTSThe results revealed that there were significant differences in the average values of the insertion/removal force due to angulation (F (2.48) = 343619, P<.05) and the type of attachment (F (7.48) = 23.220, P<.05).CONCLUSIONGreater angulation of the abutments was found to influence the retention capacity of the attachments, and the fatigue test simulating 5 years of denture insertion and removal did not produce wear in the metal abutments.

This study aimed to assess bias magnitudes, sensibility, and specificity of particular partial-mouth recording protocols (PRPs) to estimate periodontal clinical measurements and periodontal status. Methods: Estimates of mean clinical attachment loss (MCAL) and mean probing depth (MPD) were calculated for 15 different PRPs and were compared to full-mouth recording protocol (FRP) data from 402 Portuguese. Biases, relative biases and intra-class correlations for all PRPs were evaluated. Bland-Altman plots and Receiver Operating Characteristic / Area Under the Curve (ROC/AUC) analysis were used to assess the sensitivity and specificity for each PRP periodontal diagnosis. Results: Regarding MPD, Half RD6 UR/LL and RD6 UL/LR had the lowest bias observed with 0.00 mm (-0.22% and 0.22%, respectively) and all full-mouth PRPs significantly produce an underestimation. Concerning MCAL, the Half MB-B-DL UR/LR had the lowest bias observed with 0.01 mm (0.16%). Excluding CPITN, Full-Mouth PRPs outperforms in average Half Mouth PRPs correlations. The Half RD6 UR/LL had the highest AUC (0.96) with 95.5 and 97.1% of sensitivity and specificity, respectively. Conclusions: Three half-mouth PRPs (Half MB-B-DL UR/LR, Half RD6 UR/LL and Half RD6 UL/ LR) protocols can be used to estimate periodontal clinical measurements with limited bias, and high sensitivity, specificity, and concordance. All full-mouth PRPs failed to estimate pocket depth means, and for clinical attachment loss, they present less ability then half-mouth partial protocols, despite presenting high sensitivity levels. (Rev Port Estomatol Med

PurposeBone graft materials can be obtained from the patient’s own body (autologous graft), animals (xenograft), human cadavers (allograft) and synthetic materials (alloplastic bone graft). Patients may have ethical, religious or medical concerns about the origin of bone grafts, which could lead them to reject the use of certain types of bone graft in their treatments. The aim of this multicenter study, which surveyed patients from five university clinics in Portugal, France, Italy, Spain and Chile, was to analyze patients’ opinions regarding the source of bone grafts.Patients and methodsA survey composed of ten questions was translated into local languages and validated. Patients were asked about the degree of acceptance/rejection of each graft and the reasons for rejection. A chi-squared test was used to analyze statistically significant differences.ResultsThree hundred thirty patients were surveyed. The grafts that elicited the highest percentage of refusal were allograft (40.4%), autologous bone graft from an extraoral donor site (34%) and xenograft (32.7%). The grafts with the lowest rate of refusal were alloplastic (6.3%) and autologous bone grafts from an intraoral donor site (24.5%). The main reason for autologous bone rejection was the fear of pain and discomfort, for xenograft it was the fear of disease transmission and the rejection of use of animals for human benefit, and for allograft it was ethical/moral motivations and the fear of disease transmission. Religious affiliation influenced patient’s preferences.ConclusionThe origin of bone grafts is still conflictive for a high percentage of patients.

PURPOSEThe aim of this study was to compare the durability and retention of 4 types of attachments placed over computer aided design/computer aided manufacturing (CAD/CAM) titanium bars when subjected to different pH conditions.MATERIALS AND METHODSFour commercially available attachments were investigated: Hader Yellow, Hader Red, Ackerman Gold and Ackerman Stainless Steel. These attachments and Ackerman CAD/CAM titanium bars were placed in 2 vessels containing different artificial saliva solutions (pH 7/pH 4) at 37℃ for one month to simulate corrosion conditions, and they were then subjected to mechanical testing (5400 cycles of insertion and removal).RESULTSThe results revealed that there were significant differences in the average values of insertion/removal force due to the pH (F (1, 24)=9.207, P<.05) and the type of attachment (F (3, 24)=11.742, P<.05).CONCLUSIONMore acidic pH values were found to have a negative influence on the retention capacity of the attachments.

This study aimed to review clinical publications involving anterior-region resin-bonded fixed partial dentures to evaluate their survival rates vis-à-vis their materials and design. An electronic search was conducted using PubMed/MEDLINE to identify articles that reported on the longevity of anterior resin-bonded fixed dental prostheses published between 2000 and 2020. Only primary clinical studies that involved a follow-up after at least 3 years were included in this review. A statistical analysis was performed to evaluate resin-bonded fixed dental prostheses’ survival rates in relation to their materials and design. This review ultimately included 23 clinical publications, comprising prospective studies, retrospective studies, and randomized controlled trials. Its statistical analysis estimated the studied prostheses’ 5-year survival rate at 86.2% for metal-framed prostheses, 87.9% for zirconia prostheses, 93.3% for alumina prostheses, 100% for glass or ceramic prostheses, and 81.7% for fiber-reinforced composite restorations. Failure rates did not significantly differ between the different material groups or between the single- and double-retainer groups. Resin-bonded fixed dental prostheses present excellent 5-year clinical longevity in the anterior sector and a favorable benefit/risk/cost ratio. Currently, no consensus has been established on an ideal material for these restorations. Cantilever design tends to limit constraints on the prostheses’ retainers and, thus, increases their survival time. All-ceramic cantilever fixed partial dentures can be considered as a definitive therapy, given their high success and survival rates. They are an optimal solution for adolescents or young adults facing potentially continuous growth.