Zirconia CAD-CAM Crowns Behavior after Intraoral Digital Impression in Normal versus Dysfunctional Patients: 3 Years Retrospective Study

objectives: the aim of this study was to evaluate the clinical performance and possible complications of single zirconia crowns fabricated using an intraoral digital computer-aided design-computer-aided manufacturing (CAD-CAM) protocol in normal and dysfunctional patients after 3 years of follow-up. materials and methods seventy patients were included in this study. the teeth were prepared with a knife-edge marginal design, and temporary crowns were placed. digital impressions were taken using optical scanning, and the frameworks were milled using the same technology. the veneering process was performed by the same dental technician. sthe occlusal corrections were made before cementation. the outcomes were evaluated in terms of survival, failures, and complications. the marginal adaptation of the crowns was also assessed. results the digital protocol for single zirconia crowns resulted in satisfactory outcomes, with high rates of survival and minimal complications after 3 years of follow-up. the marginal adaptation of the crowns was excellent, with 93% of the restorations achieving the ideal marginal adaptation, while 7% had minor deviations. parafunctions were found in 41.9% of the prosthetic rehabilitation, but no significant differences were observed between the normal and dysfunctional groups regarding the survival and complications of the crowns. conclusion the digital protocol for single zirconia crowns is a reliable and predictable treatment option, even for patients with parafunction, when proper occlusal corrections are performed before cementation. the use of intraoral digital CAD-CAM technologies with optical impressions can simplify procedures, reduce the workflow time, and minimize the variables linked to the human factor

Influence of Modeling Liquids and Universal Adhesives Used as Lubricants on Color Stability and Translucency of Resin-Based Composites

The use of lubricants during restorative procedures is a clinically common practice to alleviate the stickiness of resin-based composite (RBCs) materials and to improve its handling. This study evaluated the effects of three modeling liquids (ML) and one universal adhesive (UA) used as lubricants during composite layering on the color stability and translucency of RBCs. Methods. The following materials were applied between every 1 mm RBC layer (total restoration height of 4 mm): GC modeling liquid (GCML, GC Corporation, Tokyo, Japan), composite wetting resin (UPWR, Ultradent Products, South Jordan, UT, USA), Bisco modeling resin (BSMR, Bisco Inc., Schaumburg, IL, USA) as an ML and Clearfil Universal Bond Quick (KUBQ, Kuraray Noritake Dental, Tokyo, Japan) as a UA. Lubricant-free specimens were used as the control. Color coordinates (L*, a* and b*) were recorded at baseline and after a simulation of 1 month of coffee consumption. Data were analyzed using ANOVA and a post hoc Tukey test (p < 0.05). Results. All lubricants induced a color change higher than the perceptibility threshold (ΔE00 > 0.81). GCML showed the highest color stability. The use of KUBQ resulted in significantly higher a* values (p = 0.001) at baseline and after staining. KUBQ and UPWR significantly influenced the color stability (ΔE00, p = 0.0001) after staining, overcoming the clinical acceptability threshold (ΔE00 > 1.77). Conclusions. The use of lubricants may affect color stability at baseline and after simulation of staining. Translucency was not affected at baseline nor after staining. Clinical Significance. Clinicians should be aware that some lubricants may affect color stability, even at baseline

Cross-cultural adaptation, reliability and validity of the Italian version of the craniofacial pain and disability inventory in patients with chronic temporomandibular joint disorders

BACKGROUND: To develop an Italian version of the Craniofacial Pain Disability Inventory (CFPDI-I) and investigate its psychometric abilities in patients with temporomandibular disorders (TMD). METHODS: The CFPDI was translated following international standards. The psychometric analyses included reliability by internal consistency (Cronbach's alpha) and test/retest stability (intraclass correlation coefficient, ICC); construct validity was investigated by matching (a priori hypotheses) the CFPDI-I with the Italian Neck Disability Index (NDI-I), a pain intensity numerical rating scale (NRS), the Italian Pain Catastrophising Scale (PCS-I), the Italian Tampa Scale of Kinesiophobia (TSK-I), and the Italian Migraine Disability Assessment Score Questionnaire (MIDAS) (Pearson's correlation). Alpha was set at 0.05. RESULTS: Two hundred and twelve patients with chronic TMD completed the tool. The questionnaire was internally consistent (\u3b1 =\u20090.95) and its stability was good (ICCs\u2009=\u20090.91). As hypothesised, validity figures showed CFPDI-I strongly correlated with the NDI-I (r =\u20090.66, p <\u20090.05) and moderately correlated with the NRS (r =\u20090.48, p <\u20090.05), PCS (r =\u20090.37, p <\u20090.05), TSKI (r =\u20090.35, p <\u20090.05) and MIDAS (r =\u20090.47, p <\u20090.05). Similar estimates were shown by CFPDI-I subscales. CONCLUSIONS: The cross-culturally adapted version of the Craniofacial Pain and Disability Inventory (CFPDI-I) showed satisfactory psychometric properties that replicate those of the original version and, therefore, can be implemented in the clinical assessment of Italian people affected by TMD

Quantitative Volumetric Enamel Loss after Orthodontic Debracketing/Debonding and Clean-Up Procedures: A Systematic Review

Objectives: To conduct a systematic review assessing quantitative enamel loss occurring after orthodontic debonding and clean-up procedures. Materials and Methods: A systematic search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was performed on different databases (Embase, Medline, Scopus, Web of Science) for papers investigating volumetric enamel loss due to bracket and clear aligner attachment debonding and/or clean-up procedures. Studies investigating in vivo and in vitro articles published in the English language until 16 July 2022 were included. The study selection was then performed by two authors who screened the abstracts independently. Results: Of 421 screened abstracts, 41 articles were selected for full-text analysis. Finally, nine studies were included in this review. No in vivo papers were retrieved. In vitro papers investigated volumetric loss caused by the removal of metal brackets (n = 7), ceramic brackets (n = 1), and both (n = 1). The clean-up procedure varied among all investigations. Impressions at baseline and after debonding/clean-up were superimposed, and the volumes were subtracted using different 3D digital analysis software. Among all included studies, the volumetric loss of enamel ranged from 0.02 ± 0.01 mm3 to 0.61 ± 0.51 mm3 per tooth. Conclusions: Debonding and clean-up procedures produce enamel loss. The debonding/clean-up procedure that is able to cause the least enamel volume loss has yet to be identified

Full-arch intraoral scanning: comparison of two different strategies and their accuracy outcomes

Aim To test if there is a difference in accuracy between full-arch scans performed as two separate halves and stitched together, or as one continuous scan from side to side. Materials and Methods A reference model with six implants was milled as a single titanium block. Six scan bodies were manufactured and screwed into the implants. A reference 3D model was created using an industrial optical scanner. The experiment was performed using the same intraoral scanning machine (3M True Definition Scanner). The ‘Stitching’ strategy had the scan started from #27 to #13;after saving this part, the same procedure was performed from #17 to #23 and the software stitched the two halves automatically. The ‘No Stitching’ strategy had the scan performed as a single procedure. Using engineering software, six copies of the scan body CAD file were substituted to the six scan bodies of the RM and the centre point of each one was determined. Linear measurements were made between the detected points; mean distance and standard deviation were calculated for each of the fifteen measurement sets created. Results Stitching and No Stitching did not show statistically significant differences (Stitching=0.0396 mm ±0.0409 mm, No Stitching=0.0452 mm ±0,0481 mm, p=.338) but they differed significantly comparing absolute errors (Stitching=0.0442 mm ±0.0358 mm, No Stitching=0.0555 mm±0,036 mm, p=.015). Conclusions Stitching showed a better precision compared to No Stitching, exhibiting a smaller standard deviation and a higher error density closer to zero

Laser versus LED polymerization: Comparison of in vitro preventive sealing procedures

Introduction: The technique of sealing is a widely accepted procedure for prevention of caries. The aim of our in vitro study was to compare the effect of two different curing units (traditional LED source and innovative laser diode lamp) on the integrity of fissure sealant material and its interface with tooth enamel. Materials and methods: Sixty healthy third molars were randomly assigned to two groups. In group A were teeth intended for polymerization by LED B lamp, and group B comprised teeth to be polymerized by an innovative laser diode. Both groups were treated with the traditional sealing technique, subjected to a metallization process, and analyzed by scanning electron microscope. Results: Micro-gaps between the sealant and the enamel were found in specimens in both A (43%) and B (40%) groups (p=0.793), and sealant shrinkage was seen. Significant differences between the groups emerged in the percentage of perimetric micro-erosion sites (80% vs. 100%, p=0.010) and the presence of holes and micro-bubbles on the sealant surface (21% vs. 63%, p=0.001). Conclusions: Although macroscopic clinical polymerization occurred with both instruments, the microscopic evaluation showed significant differences between the studied groups in terms of perimetric micro-erosion sites and micro-bubbles, which were higher in laser-cured samples

Effect of finishing systems on surface roughness and gloss of full-body bulk-fill resin composites

Background: In this study, we assess the effect produced on roughness and gloss of fullbody bulk-fill materials by different finishing and polishing systems. Methods: Four full-body bulkfill materials were tested: SonicFill2 (SF), Filtek Bulk Fill Posterior Restorative (FB), Tetric EvoCeram bulk-fill (EC), and Fill-Up! (FU). Sixty discs per material (2 mm in thickness and 7 mm in diameter) were obtained and randomly assigned (n = 15) to four finishing and polishing methods: Sof-Lex Spiral Wheels (SW), HiLusterPLUS (HL), Astropol (AP), and Opti1Step (OS). Surface roughness and gloss were then measured. Results: For roughness, material and surface treatment were significant factors (p < 0.001) with SF = FB = EC < FU and AP < SW < HL = OS. Material and surface treatment had a significant effect also on gloss (p < 0.001), with SF > FB = EC > FU and SW > AP > HL > OS. Conclusions: The tested combinations of bulk-fill and polishing systems provided clinically acceptable results with regard to roughness, while the outcome was poor for gloss. Multistep finishing/polishing systems were able to produce smoother surfaces on full-body bulk-fill materials compared to simplified ones

Prevalence of white-spot lesions before and during orthodontic treatment with fixed appliances

The aim of the study was to determine the prevalence of white-spot lesions (WSLs) in patients with fixed orthodontic appliances. The cross-sectional study sample consisted of three groups of patients: group I, 59 patients treated orthodontically for 6  months; group II, 64 patients treated for 12  months; group 0 (control), 68 patients examined immediately before appliance placement. All groups were treated with a 0.022-inch slot preadjusted appliance and they wore a functional fixed appliance. The presence of WSLs was evaluated by visual examination using the scoring system proposed by Gorelick. The groups were evaluated for differences in the prevalence of at least one WSL using Fisher’s exact test, followed by Bonferroni pairwise comparisons. The prevalence of WSLs by tooth type was evaluated with logistic regression (P  <  0.05). Intraobserver agreement was assessed by means of the Cohen ĸ statistical method. There were no significant differences in the prevalence of WSLs between patients treated for 6 and 12 months (P = 0.855); however, there were significantly more WSLs in groups I and II than in group 0 (P = 0.000). No significant differences were found between girls and boys (P = 1.000). The mandibular first molars and maxillary lateral incisors were the most affected teeth, in both the treated and untreated groups. The study revealed significant decalcification at 6 months after orthodontic bonding. Considering how quickly these lesions can develop and become irreversible, early diagnosis is of critical importance