Invisible orthodontic aligners (IOAs) have been introduced in the orthodontic field as an innovative alternative for fixed brackets, in relation to their ability to be easily inserted/removed from the oral cavity without affecting the chewing ability and the aesthetic of the patients. The paper provides a complete physicochemical and mechanical characterization of thermoplastic materials in the form of disks used for commercial IOAs. A wide palette of specific techniques is considered, from tensile tests and dynamic-mechanical analysis, to X-Ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transformation infrared spectroscopy (FTIR-ATR) analyses and water absorption tests. The disks are investigated before and after immersion into staining beverages (red wine, coffee, nicotine and artificial saliva), in terms of colour variations, transparency, and microscopic surface modifications by means of colorimetry, UV-VIS absorbance and scanning electron microscopy (SEM). Among all the samples, polyurethane (PU) exhibited the highest crystallinity and the highest values of mechanical and thermal resistance, while the poly(ethylene terephthalate)-glycol (PETG) samples presented better transparency and less ability to absorb water. Moreover, red wine and coffee give noticeable colour variations after 14 days of immersion, together with a slight reduction of transparency.

ObjectivesThe aim of this pilot study was to evaluate the periodontal effects during rapid palatal expansion (RPE) or slow palatal expansion (SPE) and to compare them by means of some clinical indices, in order to establish the possible differences and advantages of one of these treatments in periodontal terms.Methods10 patients (aged 6 to 7 years; average age 6.3 years) were submitted to RPE treatment and other 10 patients (aged 6 to 8 years, average age 6.3 years) to SPE treatment. They were treated with the Haas expander. The selected clinical indices (plaque index, PI; papillary bleeding index, PBI; probing pocket depth, PPD) were collected three times during the treatment (t0, detected 7 days after the periodontal prophylaxis, at the beginning of the active orthodontic therapy; t1, detected during the active therapy; t2, detected after retention). All measurements were performed by the same examiner. The protocol was approved by the ethics committee.ResultsThe effects of the prophylaxis were excellent to control inflammation and dental plaque before the beginning of the orthodontic-orthopaedic treatment, as in both the two groups, the PI and the PBI values were equal to 0.In the group receiving slow expansion, the PPD remained unchanged from t0 to t1, while it significantly increased from t0 to t1 in the group of rapid expansion. At t2 the values of the two groups returned to be overlapping.ConclusionsBoth rapid and slow expansion treatments present potential irritation effect (increase of PI index and PBI index) on the periodontium, suggested by the significant increase of PI and PBI from t0 to t1 in both the two groups; therefore prophylaxis and periodic controls are very important. There are no long-term benefits that might be referred unequivocally to one of the two treatments in terms of periodontal consequences, as demonstrated by the lack of significant differences between the two groups at t2.

BackgroundPulpotomy is the surgical removal of the entire coronal pulp with preservation of the radicular pulp vitality. The purpose of this retrospective study was to evaluate the clinical and radiographic success of pulpotomy of primary molars using two materials, biodentine and calcium hydroxide.MethodsRecords of 400 primary molars in 360 paediatric participants (mean age: 7.5 ± 1.6 years, ranging from 5 to 9 years) with dental caries who required pulp therapy were included in this study. Biodentine was used on 200 teeth, and calcium hydroxide (CH) was used on another 200 teeth, as a pulpotomy material. Clinical and radiographic evaluation was performed after 9 and 18 months. Statistical analysis was evaluated with the chi-squared test, and the level of significance was set at p < 0.05.ResultsThe treatment success with CH was 85.5% after 9 months and 79.5% after 18 months, while the success rate of biodentine was 94% after 9 months and 89.5% after 18 months. The statistical analysis with the Chi-squared test showed that the clinical and radiographic success rate with biodentine was significantly higher than CH (p < 0.05).ConclusionsBiodentine exhibited a higher clinical and radiographic success rate compared to CH. However, besides the clinical results, biodentine has some disadvantages, such as higher costs, compared to CH.

Background: Given the increasing request for natural pharmacological molecules, this study assessed the antimicrobial capacity of Pistacia lentiscus L. essential oil (PLL-EO) obtained from the leaves of wild plants growing in North Sardinia (Italy) toward a wide range of periodontal bacteria and Candida, including laboratory and clinical isolates sp., together with its anti-inflammatory activity and safety. Methods: PLL-EO was screened by gas chromatography/mass spectrometry. The minimal inhibitory concentration (MIC) was determined. The anti-inflammatory activity was measured by cyclooxygenase (COX-1/2) and lipoxygenase (LOX) inhibition, while the antioxidant capacity was determined electro-chemically and by the MTT assay. The WST-1 assay was used to ascertain cytotoxicity toward four lines of oral cells. Results: According to the concentrations of terpens, PLL-EO is a pharmacologically-active phytocomplex. MICs against periodontal bacteria ranged between 3.13 and 12.5 µg/ml, while against Candida sp. they were between 6.25 and 12.5 µg/mL. Oxidation by COX-1/2 and LOX was inhibited by 80% and 20% µg/mL of the oil, respectively. Antioxidant activity seemed negligible, and no cytotoxicity arose. Conclusions: PLL-EO exhibits a broad-spectrum activity against periodontal bacteria and Candida, with an interesting dual inhibitory capacity toward COX-2 and LOX inflammatory enzymes, and without side effects against oral cells.

In view of the increasing interest in natural antimicrobial molecules, this study screened the ability of Thymus capitatus (TC) essential oil and Citrus limon var. pompia (CLP) extract as raw extracts or incorporated in vesicular nanocarriers against Streptococcus mutans and Candida albicans. After fingerprint, TC or CLP were mixed with lecithin and water to produce liposomes, or different ratios of water/glycerol or water/propylene glycol (PG) to produce glycerosomes and penetration enhancer vesicles (PEVs), respectively. Neither the raw extracts nor the nanovesicles showed cytotoxicity against human gingival fibroblasts at all the concentrations tested (1, 10, 100 μg/mL). The disc diffusion method, MIC-MBC/MFC, time-kill assay, and transmission electron microscopy (TEM) demonstrated the highest antimicrobial potential of TC against S. mutans and C. albicans. The very high presence of the phenol, carvacrol, in TC (90.1%) could explain the lethal effect against the yeast, killing up to 70% of Candida and not just arresting its growth. CLP, rich in polyphenols, acted in a similar way to TC in reducing S. mutans, while the data showed a fungistatic rather than a fungicidal activity. The phospholipid vesicles behaved similarly, suggesting that the transported extract was not the only factor to be considered in the outcomes, but also their components had an important role. Even if other investigations are necessary, TC and CLP incorporated in nanocarriers could be a promising and safe antimicrobial in caries prevention.