Effect of quadrantwise versus full-mouth subgingival instrumentation on clinical and microbiological parameters in periodontitis patients: A randomized clinical trial.

AIM: This study evaluated the efficacy of quadrantwise subgingival instrumentation (Q-SI) versus one-stage full-mouth subgingival instrumentation (FM-SI) on probing depth and periodontal pathogen reduction over a 6-month follow-up period, as well as whether baseline periodontal pathogens influenced the impact of periodontal treatment protocols on outcomes. METHODS: Patients with periodontitis were randomized to receive Q-SI (n = 43) or FM-SI (n = 45). Patients were instructed and motivated to maintain optimal oral hygiene during the treatment sessions. Clinical (probing pocket depth [PPD], clinical attachment loss [CAL], and bleeding on probing [BOP]) and periodontal pathogens were assessed at baseline and after 30, 90, and 180 days. Total bacterial load and periodontal pathogens were analysed via real-time PCR. RESULTS: At the 6-month follow-up, the median PPD decreased from 4.8 mm (interquartile range [IQR]: 4.3-5.2) to 2.6 mm (IQR: 2.3-2.9) in FM-SI patients and from 4.7 mm (IQR: 4.1-5.2) to 3.2 mm (IQR: 2.4-3.5) in Q-SI patients (p < .001). At 6 months, FM-SI was more effective at reducing the median proportions of Porphyromonas gingivalis (Pg), Aggregatibacter actinocomyctemcomitans, and Tannerella forsythia (Tf) (p < .001 for each value). Multilevel linear regression analysis demonstrated that high baseline PPD (p = .029), Pg (p = .014), and Tf (p < .001) levels and the FM-SI protocol (p < .001) were statistically significant predictors of PPD reduction at 6 months. Furthermore, PPD reduction was significantly greater in the FM-SI group when lower baseline Pg levels were detected. CONCLUSION: The FM-SI was more effective than the Q-SI in reducing the mean PPD and number of periodontal pathogens in periodontitis patients over a 6-month follow-up period. Higher baseline PPD and Pg levels had a negative impact on PPD reduction at 6 months after FM-SI.

Insights and Advancements in Periodontal Tissue Engineering and Bone Regeneration.

The regeneration of periodontal bone defects continues to be an essential therapeutic concern in dental biomaterials. Numerous biomaterials have been utilized in this sector so far. However, the immune response and vascularity in defect regions may be disregarded when evaluating the effectiveness of biomaterials for bone repair. Among several regenerative treatments, the most recent technique of in situ tissue engineering stands out for its ability to replicate endogenous restorative processes by combining scaffold with particular growth factors. Regenerative medicine solutions that combine biomaterials/scaffolds, cells, and bioactive substances have attracted significant interest, particularly for bone repair and regeneration. Dental stem cells (DSCs) share the same progenitor and immunomodulatory properties as other types of MSCs, and because they are easily isolable, they are regarded as desirable therapeutic agents in regenerative dentistry. Recent research has demonstrated that DSCs sown on newly designed synthetic bio-material scaffolds preserve their proliferative capacity while exhibiting increased differentiation and immuno-suppressive capabilities. As researchers discovered how short peptide sequences modify the adhesion and proliferative capacities of scaffolds by activating or inhibiting conventional osteogenic pathways, the scaffolds became more effective at priming MSCs. In this review, the many components of tissue engineering applied to bone engineering will be examined, and the impact of biomaterials on periodontal regeneration and bone cellular biology/molecular genetics will be addressed and updated.

Burden of infectious disease studies in Europe and the United Kingdom: a review of methodological design choices.

This systematic literature review aimed to provide an overview of the characteristics and methods used in studies applying the disability-adjusted life years (DALY) concept for infectious diseases within European Union (EU)/European Economic Area (EEA)/European Free Trade Association (EFTA) countries and the United Kingdom. Electronic databases and grey literature were searched for articles reporting the assessment of DALY and its components. We considered studies in which researchers performed DALY calculations using primary epidemiological data input sources. We screened 3053 studies of which 2948 were excluded and 105 studies met our inclusion criteria. Of these studies, 22 were multi-country and 83 were single-country studies, of which 46 were from the Netherlands. Food- and water-borne diseases were the most frequently studied infectious diseases. Between 2015 and 2022, the number of burden of infectious disease studies was 1.6 times higher compared to that published between 2000 and 2014. Almost all studies (97%) estimated DALYs based on the incidence- and pathogen-based approach and without social weighting functions; however, there was less methodological consensus with regards to the disability weights and life tables that were applied. The number of burden of infectious disease studies undertaken across Europe has increased over time. Development and use of guidelines will promote performing burden of infectious disease studies and facilitate comparability of the results.

Impact of periodontitis on gingival crevicular fluid miRNAs profiles associated with cardiovascular disease risk.

BACKGROUND AND OBJECTIVE: Recent emerging evidence has shown that microRNA (miRNAs) is involved in several epigenetic processes linked with periodontitis, increased oxidative stress and cardiovascular disease (CVD). The present study aimed to assess the impact of periodontitis on gingival crevicular fluid (GCF) miRNAs expression associated with CVD risk and to evaluate possible confounders that influenced this association. MATERIALS AND METHODS: For the present study, healthy controls (n = 28) and subjects with CVD (n = 28), periodontitis (n = 30) and periodontitis + CVD (n = 29) were enrolled. All subjects underwent regular periodontal examinations and blood sampling. In addition, GCF sampling was performed, and miRNAs 7a-5p, 21-3p, 21-5p, 100-5p, 125-5p, 200b-3p, and 200b-5p expression was analyzed using a real-time quantitative polymerase chain reaction (RT-PCR). RESULTS: The results showed that periodontitis and periodontitis + CVD subjects presented significantly different GCF miRNAs expression compared to healthy controls and CVD subjects. More specifically, compared to healthy controls and CVD, subjects with periodontitis and periodontitis + CVD showed higher GCF miRNA 7a-5p, miRNA 21-3p, miRNA 21-5p, miRNA 200b-3p, and miRNA 200b-5p (p < .05) and lower miRNA 100-5p, miRNA 125-5p levels (p < .05). Furthermore, the multivariate regression analysis evidenced that periodontitis (miRNA 21-3p, 100-5p) and periodontal inflamed surface area (PISA) (miRNA 7a-5p, 21-3p, 21-5p, 100-5p, 125-5p, 200b-3p) were significant predictors of GCF miRNAs concentration (p < .05). CONCLUSION: The results of the study highlighted that the periodontitis and periodontitis + CVD group showed higher GCF miRNAs expression than healthy controls and CVD subjects. Furthermore, periodontitis and its extent (PISA) were revealed as significant predictors of GCF miRNAs associated with CVD risk.

Inequalities in the burden of non-communicable diseases across European countries: a systematic analysis of the Global Burden of Disease 2019 study.

BACKGROUND: Although overall health status in the last decades improved, health inequalities due to non-communicable diseases (NCDs) persist between and within European countries. There is a lack of studies giving insights into health inequalities related to NCDs in the European Economic Area (EEA) countries. Therefore, the aim of the present study was to quantify health inequalities in age-standardized disability adjusted life years (DALY) rates for NCDs overall and 12 specific NCDs across 30 EEA countries between 1990 and 2019. Also, this study aimed to determine trends in health inequalities and to identify those NCDs where the inequalities were the highest. METHODS: DALY rate ratios were calculated to determine and compare inequalities between the 30 EEA countries, by sex, and across time. Annual rate of change was used to determine the differences in DALY rate between 1990 and 2019 for males and females. The Gini Coefficient (GC) was used to measure the DALY rate inequalities across countries, and the Slope Index of Inequality (SII) to estimate the average absolute difference in DALY rate across countries. RESULTS: Between 1990 and 2019, there was an overall declining trend in DALY rate, with larger declines among females compared to males. Among EEA countries, in 2019 the highest NCD DALY rate for both sexes were observed for Bulgaria. For the whole period, the highest DALY rate ratios were identified for digestive diseases, diabetes and kidney diseases, substance use disorders, cardiovascular diseases (CVD), and chronic respiratory diseases - representing the highest inequality between countries. In 2019, the highest DALY rate ratio was found between Bulgaria and Iceland for males. GC and SII indicated that the highest inequalities were due to CVD for most of the study period - however, overall levels of inequality were low. CONCLUSIONS: The inequality in level 1 NCDs DALYs rate is relatively low among all the countries. CVDs, digestive diseases, diabetes and kidney diseases, substance use disorders, and chronic respiratory diseases are the NCDs that exhibit higher levels of inequality across countries in the EEA. This might be mitigated by applying tailored preventive measures and enabling healthcare access.

Resolution of peri-implant mucositis at tissue- and bone-level implants: A 6-month prospective controlled clinical trial.

OBJECTIVE: The objective of the study was to compare resolution of inflammation of naturally occurring peri-implant mucositis (PM) at tissue-level (TL) and bone-level (BL) implants after non-surgical mechanical debridement. MATERIALS AND METHODS: Fifty-four patients with 74 Implants with PM were allocated in two groups (39 TL and 35 BL implants) and treated by means of subgingival debridement using a sonic scaler with a plastic tip without adjunctive measures. At baseline and at 1, 3, 6 months, the full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), probing depth (PD), bleeding on probing (BOP), and modified plaque index (mPlI) were recorded. The primary outcome was BOP change. RESULTS: After 6 months, the FMPS, FMBS, PD, and number of implants with plaque decreased statistically significantly in each group (p < .05); however, no statistically significant differences were found between TL and BL implants (p > .05). After 6 months, 17 (43.6%) TL and 14 (40%) BL implants showed a BOP change in (17.9%) and (11.4%), respectively. No statistical difference was recorded between groups. CONCLUSIONS: Within the limitations of present study, the findings showed no statistically significant differences in terms of changes in clinical parameters following non-surgical mechanical treatment of PM at TL and BL implants. A complete resolution of PM (i.e., no BOP at all implant sites) was not achieved in both groups.

Analysis of the response to two pharmacological protocols in patients with oral lichen planus: A randomized clinical trial.

OBJECTIVE: To evaluate the effectiveness of two different therapies on oral lichen planus (OLP) treatment through the analysis of OLP symptoms and signs and to analyze the risk of side effects related to the adopted protocols. METHODS: Thirty-eight patients with OLP were selected according to van der Meij and van der Waal clinical and histopathological criteria. Through a randomized design, 19 patients received Tacrolimus 0.1% ointment (T group) and 19 an anti-inflammatory mouthwash (M group) composed of calcium hydroxide 10%, hyaluronic acid 0.3%, umbelliferone, and oligomeric proanthocyanidins. The patients were examined on a regular basis for OLP symptoms, signs, and disease severity score changes over a 3-month follow-up period. RESULTS: Both treatments were effective in the reduction of OLP signs and symptoms. However, at 3 months (T3), in comparison with the M group, T group patients showed significantly lower mean values of OLP signs (p = 0.035), symptoms (p = 0.045), and disease severity scores (p = 0.041). Moreover, the Spearman test showed that there was a significant correlation between OLP signs and symptoms at each follow-up session in all patients. CONCLUSIONS: Both treatments demonstrated a significant approach to control OLP. However, tacrolimus determined a more effective improvement in OLP signs and symptoms compared to anti-inflammatory mouthwash at 3-month follow-up.

Analysis of oral lichen planus severity on micro-RNA linked with malignant transformation risks.

OBJECTIVE: The present study evaluated the oral tissue expression of micro-RNA (miRNAs) linked to the potential malignant evolution of oral lichen planus (OLP). Furthermore, the correlation between OLP severity and miRNAs expression was assessed, and possible predictors of miRNAs in OLP patients were identified. METHODS: The present study enrolled 41 patients with OLP (median age 58 years) and 42 healthy controls (median age 59 years). In each patient, miRNA levels (miR-7a-3p,-7a2-3p,-7a-5p,-21-3p,-21-5p,-100-3p,-100-5p,-125b-2-3p,-125b-5p,-200b-3p,-200b-5p) were assessed and analyzed through reverse transcription polymerase chain reaction. Clinical parameters and the eventual presence of OLP symptoms, signs, and disease severity scores in each patient were reported using an anamnestic questionnaire. RESULTS: In comparison with healthy controls, OLP patients showed significantly higher miR-7a-3p,-7a-2-3p,-21-3p, miR-21-5p and miR-100-5p levels (p < 0.05) and significantly lower miR-125b-2-3p,-125b-5p,-200b-3p, and -200b-5p levels (p < 0.05). Furthermore, OLP symptoms and signs and disease severity scores were significantly correlated and were also predictors of all analyzed miRNAs (p < 0.05). CONCLUSIONS: In comparison with healthy subjects, OLP patients exhibited unbalanced oral miRNAs expression linked to the risk of potential malignant evolution of OLP. Furthermore, some miRNAs were correlated with OLP extent and were significant predictors of OLP symptoms, signs, and disease severity scores.

Periodontal Health and Disease in the Context of Systemic Diseases.

During recent years, considerable progress has been made in understanding the etiopathogenesis of periodontitis in its various forms and their interactions with the host. Furthermore, a number of reports have highlighted the importance of oral health and disease in systemic conditions, especially cardiovascular diseases and diabetes. In this regard, research has attempted to explain the role of periodontitis in promoting alteration in distant sites and organs. Recently, DNA sequencing studies have revealed how oral infections can occur in distant sites such as the colon, reproductive tissues, metabolic diseases, and atheromas. The objective of this review is to describe and update the emerging evidence and knowledge regarding the association between periodontitis and systemic disease and to analyse the evidence that has reported periodontitis as a risk factor for the development of various forms of systemic diseases in order to provide a better understanding of the possible shared etiopathogenetic pathways between periodontitis and the different forms of systemic diseases.

Prospective Advances in Genome Editing Investigation.

Genomic editing technology has been developed since 2010 through the use of some techniques, such as the clustered regularly interspaced short palindromic repeat (CRISPR) DNA sequences/CRISPR-associated (Cas) type-9 method, or through genetic manipulation tools derived from host response systems from some microbes (e.g., bacteria) against plasmids and viruses. The introduction of the CRISPR/Cas9 method as a genome-editing instrument represented an important step in the advancement of the genome-editing method thanks to the ease and effectiveness of use as well as the great adaptability to different biomedical areas. This paragraph will discuss all conceived technologies and new perspectives that can be applied in treating some associated genetic disorders, such as cardiovascular diseases, metabolic diseases, inflammatory diseases, and tumors by means of reversible and modulating control of gene expression epigenetics using genetic editing techniques.

Tooth automatic segmentation from CBCT images: a systematic review.

OBJECTIVES: To describe the current state of the art regarding technological advances in full-automatic tooth segmentation approaches from 3D cone-beam computed tomography (CBCT) images. MATERIALS AND METHODS: In March 2023, a search strategy without a timeline setting was carried out through a combination of MeSH terms and free text words pooled through Boolean operators ('AND', 'OR') on the following databases: PubMed, Scopus, Web of Science and IEEE Explore. Randomized and non-randomized controlled trials, cohort, case-control, cross-sectional and retrospective studies in the English language only were included. RESULTS: The search strategy identified 541 articles, of which 23 have been selected. The most employed segmentation methods were based on deep learning approaches. One article exposed an automatic approach for tooth segmentation based on a watershed algorithm and another article used an improved level set method. Four studies presented classical machine learning and thresholding approaches. The most employed metric for evaluating segmentation performance was the Dice similarity index which ranged from 90 ± 3% to 97.9 ± 1.5%. CONCLUSIONS: Thresholding appeared not reliable for tooth segmentation from CBCT images, whereas convolutional neural networks (CNNs) have been demonstrated as the most promising approach. CNNs could help overcome tooth segmentation's main limitations from CBCT images related to root anatomy, heavy scattering, immature teeth, metal artifacts and time consumption. New studies with uniform protocols and evaluation metrics with random sampling and blinding for data analysis are encouraged to objectively compare the different deep learning architectures' reliability. CLINICAL RELEVANCE: Automatic tooth segmentation's best performance has been obtained through CNNs for the different ambits of digital dentistry.

Impact of periodontitis on circulating cell-free DNA levels as a measure of cardiovascular disease.

OBJECTIVES: The present study aims to assess the serum circulating cell-free (cfDNA) concentrations in patients with periodontitis and cardiovascular disease (CVD) and to evaluate the impact of periodontitis on circulating cfDNA levels and the confounding factors that might mediated the possible relationship. MATERIALS AND METHODS: Healthy controls (n=30) and patients with CVD (n=31), periodontitis (n=31), and periodontitis + CVD (n=30) were enrolled in the present study. All subjects underwent regular periodontal examination and blood sampling and cfDNA evaluation. The analysis of the plasma cfDNA concentrations was performed using a dsDNA Assay Kit. RESULTS: In comparison with healthy controls and CVD patients, periodontitis and periodontitis+CVD exhibited significantly higher expression of circulating cfDNA (p<0.05). There was a positive correlation among plasma cfDNA and clinical attachment loss (CAL) (p=0.019), high sensitivity C-reactive protein (hs-CRP) (p=0.027), and periodontal inflamed surface area (PISA) (p=0.003). Furthermore, the multivariate regression analysis evidenced that PISA (p<0.001), hs-CRP (p=0.014), and full-mouth bleeding score (FMBS) (p=0.004) were significant predictors of circulating cfDNA concentrations. CONCLUSIONS: The results of the study highlighted that the periodontitis and periodontitis + CVD group showed higher circulating cfDNA expression in comparison with healthy controls and CVD patients. Moreover, the extent of periodontitis was correlated with the increased cfDNA levels and represented a significant predictor of the increased circulating cfDNA concentrations. CLINICAL RELEVANCE: Unbalanced circulating cfDNA concentrations have been indicated to represent a possible risk of CVD and endothelial dysfunction. Periodontitis and periodontitis + CVD patients showed higher circulating cfDNA expression; moreover, the extent of periodontitis significantly predicted higher circulating cfDNA concentrations, suggesting the potential increased risk of developing CVD in periodontitis patients.

Conservative treatment of temporomandibular joint condylar fractures: A systematic review conducted according to PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions.

OBJECTIVE: Fractures of the mandibular condyle are the most common jaw fractures. There are several treatment approaches. There is the non-surgical and surgical approach. The purpose of this systematic literature review is to evaluate the indications and contraindications of either method to help the clinician make the best treatment choice. METHODS: Pubmed, Web of Science and Lilacs were systematically searched until 20 May 2023. Clinical trials were selected to compare the two treatments for condyle fracture and evaluate indications and contraindications. RESULTS: Out of 2515 papers, four studies were included. The surgical approach allows faster functional recovery and decreases patient discomfort. The study analyses under what circumstances a surgical procedure is more practical than a non-surgical one. CONCLUSION: There is no evidence regarding the reliability of either method. Both have superimposable results. However, age, type of occlusion and other factors direct the clinician towards a surgical choice.

Prevalence of bruxism in obstructive sleep apnea syndrome (OSAS) patients: A systematic review conducted according to PRISMA guidelines and the cochrane handbook for systematic reviews of interventions.

BACKGROUND: Sleep bruxism (SB) and obstructive sleep apnea syndrome (OSAS) are two sleep-related conditions that have been associated with significantly conflicting results in literature. Understanding the prevalence of bruxism among OSA patients is crucial for identifying possible comorbidities and optimising treatment strategies. OBJECTIVE: This systematic review aimed at analysing the prevalence of SB in OSAS sufferers and understanding the association between the two. METHODS: Five online databases were searched for relevant articles in accordance with the PRISMA guidelines for conduction of systematic reviews. Studies reporting the prevalence of bruxism in OSAS patients and diagnosed through clinical assessments or polysomnography were included. Data extraction and quality assessment were performed independently by two reviewers. Methodological quality of the included studies was assessed using Risk of Bias In Non-randomised Studies of Interventions (ROBINS-I). RESULTS: A thorough search of literature yielded only two studies were eligible for this review. SB was found to be significantly present in the OSAS group. Despite methodological variations, the majority of studies reported higher rates of bruxism in OSAS patients compared to the general population or control groups. CONCLUSION: The results of this systematic review point to a significant association between bruxism and obstructive sleep apnea. Further research is required to determine a more precise prevalence rate and investigate the potential therapeutic implications of the bruxism-OSAS association that uses a standardised assessment techniques and larger sample sizes.

Biomarkers from Peri-Implant Crevicular Fluid (PICF) as Predictors of Peri-Implant Bone Loss: A Systematic Review.

The aim of the present systematic review is to summarize current knowledge regarding the analysis of biomarkers extracted from peri-implant crevicular fluid (PICF) as predictors of peri-implant bone loss (BL). An electronic search was conducted on three databases, PubMed/MEDLINE, Cochrane Library, and Google Scholar, to find clinical trials published until 1 December 2022 suitable to answer the following focused question: in patients with dental implants, are biomarkers harvested from PICF predictive of peri-implant BL? The initial search yielded a total of 158 entries. After a full-text review and application of the eligibility criteria, the final selection consisted of nine articles. The risk of bias in included studies was assessed using the Joanna Briggs Institute Critical Appraisal tools (JBI). According to the present systematic review, some inflammatory biomarkers harvested from PICF (collagenase-2, collagenase-3, ALP, EA, gelatinase b, NTx, procalcitonin, IL-1ß, and several miRNAs) seem to be correlated with peri-implant BL and may assist in the early diagnosis of pathological BL, that characterizes peri-implantitis. MiRNA expression demonstrated a predictive potential of peri-implant BL that could be useful for host-targeted preventive and therapeutic purposes. PICF sampling may represent a promising, noninvasive, and repeatable form of liquid biopsy in implant dentistry.

Impact of Circulating Cell-Free DNA (cfDNA) as a Biomarker of the Development and Evolution of Periodontitis.

In the last few decades, circulating cell-free DNA (cfDNA) has been shown to have an important role in cell apoptosis or necrosis, including in the development and evolution of several tumors and inflammatory diseases in humans. In this regard, periodontitis, a chronic inflammatory disease that can induce the destruction of supporting components of the teeth, could represent a chronic inflammatory stimulus linked to a various range of systemic inflammatory diseases. Recently, a possible correlation between periodontal disease and cfDNA has been shown, representing new important diagnostic-therapeutic perspectives. During the development of periodontitis, cfDNA is released in biological fluids such as blood, saliva, urine and other body fluids and represents an important index of inflammation. Due to the possibility of withdrawing some of these liquids in a non-invasive way, cfDNA could be used as a possible biomarker for periodontal disease. In addition, discovering a proportional relationship between cfDNA levels and the severity of periodontitis, expressed through the disease extent, could open the prospect of using cfDNA as a possible therapeutic target. The aim of this article is to report what researchers have discovered in recent years about circulating cfDNA in the development, evolution and therapy of periodontitis. The analyzed literature review shows that cfDNA has considerable potential as a diagnostic, therapeutic biomarker and therapeutic target in periodontal disease; however, further studies are needed for cfDNA to be used in clinical practice.

A Reciprocal Link between Oral, Gut Microbiota during Periodontitis: The Potential Role of Probiotics in Reducing Dysbiosis-Induced Inflammation.

Human body is colonized by a florid microbial community of bacteria, archaea, fungi, protists, helminths, and viruses, known as microbiota, which co-evolves with the host and influences its health through all stages of its life. It is well known that oral microorganisms form highly structurally and functionally organized multi-species biofilms and establish a network of complex mutual inter-species interactions having a primary function in synergy, signaling, or antagonism. This ecological model allows the microorganisms to increase their resistance to antimicrobial agents and settle a balanced microbes-host symbiotic relationship that ensures oral and global health status in humans. The host-associated microbiome is an important factor in human health and disease. Therefore, to develop novel diagnostic, therapeutic, and preventive strategies, microbiome's functions and the reciprocal interactions every microbiome entertains with other microbial communities in the human body are being investigated. This review provides an analysis of the literature about the close connection between the two largest microbial communities in humans: the oral and the gut microbiomes. Furthermore, it focuses on how the alteration of their microbial and functional characteristics can lead to and reciprocally influence the onset of both oral and intestinal microbiome-associated illness, along with the potential role of probiotics in ameliorating inflammation and microbial dysbiosis.

Accuracy (trueness and precision) of 3D printed orthodontic models finalized to clear aligners production, testing crowded and spaced dentition.

BACKGROUND: The study's objective was to assess the accuracy (trueness and precision) of orthodontic models obtained from crowded and spaced dentition finalized for the production of clear aligners. Four 3D printers featuring different technologies and market segments were used for this purpose. METHODS: Two digital master models were obtained from two patients featuring respectively crowded dentition (CM group) and diastema/edentulous spaces (DEM group). The 3D printers tested were: Form 3B (SLA technology, medium-professional segment), Vector 3SP (SLA technology, industrial segment), Asiga Pro 4K65 (DLP technology, high-professional segment), and Anycubic Photon M3 (LCD technology, entry-level segment). Each 3D printed model was scanned and superimposed onto the reference master model and digital deviation analysis was performed to assess the trueness and precision calculated as root mean square (RMS). All data were statistically examined to obtain intra-group and inter-groups comparisons(p 0.05). RESULTS: In both CM and DEM groups, SLA 3D printers (Vector 3SP and Form 3B) showed lower trueness error compared to DLP/LCD technologies (Asiga Pro 4K65, Anycubic Photon M3) (p < 0.001). In general, the entry-level printer (Anycubic Photon M3) showed the greatest trueness error (p < 0.001). Comparing CM and DEM models generated with the same 3D printer, statistically significant differences were found only for Asiga Pro 4k65 and Anycubic Photon M3 printers (p > 0.05). Concerning data of precision, the DLP technology (Asiga Pro 4k65) showed lower error compared to the other 3D printers tested. The trueness and precision errors were within the accepted clinical error for clear aligner manufacturing (< 0.25 mm), with the entry-level 3D printer nearly reaching this value. CONCLUSIONS: The accuracy of orthodontic models generated for clear aligners can be affected by different 3D printer technologies and anatomical characteristics of dental arches.

Palatal changes after treatment of functional posterior cross-bite using elastodontic appliances: a 3D imaging study using deviation analysis and surface-to-surface matching technique.

BACKGROUND: The present study aimed to evaluate the changes in palate dimension and morphology after treatment of functional posterior crossbite (FPXB) with elastodontic devices (EAs). METHODS: The treatment group (TG) consisted of 25 subjects (mean age 7.3 ± 0.9 years) who received treatment with EA for one year. The control group (CG) comprised 14 untreated subjects (mean age 6.8 ± 0.7 years). INCLUSION CRITERIA: intra-oral scan registered before (T0) and after treatment (T1), FPXB with a mandibular shift towards the crossbite site of ≥ 2 mm, class I molar relationship. EXCLUSION CRITERIA: missing teeth, anterior crossbite, temporomandibular disorders, previous orthodontic treatment, carious lesions, mobility of deciduous posterior teeth, craniofacial deformities. Digital models were analyzed to assess the inter-canine (ICW) and inter-molar widths (IMW) and the corresponding emi-lateral measurements (eICW and eIMW) using the median palatine plane as reference. According to a specific 3D imaging technology, the morphology and symmetry of the palate was investigated by analysing the 3D deviation between the two specular models of the palate. RESULTS: At T0, both groups showed a significantly narrower dimension of eICW and eIMW at the crossbite side compared to the non-crossbite side (p < 0.05). Also, the 3D deviation analysis demonstrates a limited matching percentage of the original/mirrored models in both TG (81.12%) and CG (79.36%), confirming the asymmetry of the palate. The area of mis-matching was located at the alveolar bone level. At T1, subjects in the TG showed a significant increment of ICW and IMW (p < 0.05), a reduction of the differences of eICW and eIMW between both sides (p < 0.05) and an increment of the percentage matching (TG = 92.32%) (p < 0.05), suggesting a significant recovery of the palatal asymmetry. No significant changes were found between T0 and T1 in the CG (p > 0.05). CONCLUSIONS: EAs could be successfully used to correct FPXB in mixed dentition and could restore the harmonious development of the palate in children.

External root resorption and rapid maxillary expansion in the short-term: a CBCT comparative study between tooth-borne and bone-borne appliances, using 3D imaging digital technology.

BACKGROUND: The aim of the study was to analyze and compare external root resorption (ERR) in patients treated with tooth-borne (TB) and bone-borne (BB) rapid maxillary expansion (RME). METHODS: The sample included 40 subjects who received tooth-borne RME (TB group, average age: 13.1 ± 1.08 years) or bone-borne RME (BB group, average age: 14.5 ± 1.11 years) and Cone-beam computed tomography (CBCT) scans before treatment (T0) and after 3-month of retention (T1). A specific 3D Imaging technology was used to generate 3D models of posterior dentition (M1 = maxillary first molars, P2 = second premolars, P1 = first premolar) and calculate volumetric data (mean and percentage values) and shape changes, the latter obtained from deviation analysis between the radicular models at different time points. Evaluation of radicular length changes was performed for each tooth. Data were statistically analysed to perform intra-timing and inter-groups comparisons. RESULTS: A significant reduction of radicular volume and length was found in posterior dentition in both groups (p < 0.05), and the M1 (volume) and its palatal root (length) were mostly involved in this response. No differences were found between M1, P1 and P2 (p > 0.05) when volumetric changes were calculated as percentage of the total volume. Deviation analysis revealed that the radicular areas mostly affected by shape change were the apex and bucco-medial side. The amount of ERR was significantly greater in TB group compared to BB group. CONCLUSIONS: BB-RME treatment could reduce the amount of ERR at the post-expansion stage.