The step further smile virtual planning: milled versus prototyped mock-ups for the evaluation of the designed smile characteristics

Digital resources for surgical and restorative treatment of excessive gingival display in one session

OBJECTIVE

This article aims to showcase the implementation of a digital workflow in addressing a case of multifactorial excessive gingival display in a patient with high esthetic demands, incorporating both surgical and restorative interventions in a single session.

CLINICAL CONSIDERATIONS

A 28-year-old female patient presented with excessive gingival display, attributed to a combination of short teeth due to altered passive eruption, lip hyperactivity, and a sub-nasal depression that lodged the upper lip during spontaneous smiling. The multidisciplinary treatment strategy encompassed surgical crown lengthening, the placement of a biovolume in the maxillary concavity, and the rehabilitation of the six anterior teeth with direct composite resin, all done in a single session. Smilecloud Biometrics was used to digitally plan the smile, and the final wax-up/mock-up was approved by the patient prior to any irreversible procedure. A digital planning center (GuiderLab) enabled the materialization of the virtual planning and the printing of the periodontal surgical guide, the biovolume, and the resin layering guides for the restorative technique.

CONCLUSIONS

Adopting a digital workflow in multidisciplinary cases with excessive gingival display leads to predictable and more expedited outcomes, ensuring a favorable result between soft and hard tissues.

CLINICAL SIGNIFICANCE

Excessive gingival display is a condition with multifactorial etiologies, including dentoalveolar, periodontal, skeletal, or muscular origins, or a combination of these factors. The diagnoses of altered passive eruption and a hypermobile upper lip are common in daily clinical practice and can be successfully managed through surgical crown lengthening and filling of the maxillary concavity, respectively. To achieve the desired outcome, restorative procedures often complement these surgical interventions.

Pregnancy related factors and temporomandibular disorders evaluated through the diagnostic criteria for temporomandibular disorders (DC/TMD) axis II: a cross sectional study

INTRODUCTION

Temporomandibular disorder (TMD) is a multifaceted condition impacting the chewing system, with its frequency varying across different age groups and showing a higher incidence in women. The involvement of estrogen in TMD has been examined due to the presence of estrogen receptors in the TMJ area. However, the exact effect of estrogen on TMD is complex. During pregnancy, marked by significant hormonal fluctuations, the impact on TMD has been hypothesized but remains unclear due to inconsistent results from various studies.

METHODS

In this cross-sectional study, we enrolled 32 pregnant women consecutively. We gathered information on demographics, TMD evaluations (using the Graded Chronic Pain Scale, Jaw Functional Limitation Scale-20, and Oral Behaviors Checklist), and mental health assessments (including Patient Health Questionnaire-9, Patient Health Questionnaire-15, and Generalized Anxiety Disorder-7). We employed descriptive statistics to summarize continuous and categorical data and used t-tests and chi-square tests for comparisons. We also conducted multivariate linear regression, adjusted for demographic factors, to investigate correlations.

RESULTS

The study group mainly consisted of women aged 30-35 (40.6%) and 25-30 (18.8%). Most participants had completed high school (50%) and were married (71.9%). A notable association was found between younger women (under 30) and higher levels of somatic symptoms (p = 0.008) and generalized anxiety (p = 0.015). Women in their second trimester showed lower severity of somatic symptoms (p = 0.04). A significant link was also observed between depression severity and somatic symptom severity (p = 0.01). However, we found no significant correlations with other TMD-related health aspects.

DISCUSSION

Our study identified significant associations between psychosomatic and psychological symptoms with variables like age and pregnancy trimester in pregnant women. However, it notably failed to establish a clear relationship between pregnancy-related factors and the severity of temporomandibular disorders (TMD). More comprehensive studies with larger participant pools are necessary to further validate and expand these findings.

Accuracy of computer-aided design trial restorations fabricated with different digital workflows

STATEMENT OF PROBLEM

Trial restorations are a versatile tool for visualizing the esthetic treatment plan and should be an accurate replica of the planned smile design. The accuracy of conventionally fabricated trial restorations has been investigated; however, studies on the accuracy of different digital workflows for trial restoration fabrication are lacking.

PURPOSE

The purpose of this in vitro study was to evaluate the accuracy of computer-aided design (CAD) trial restorations fabricated with different digital workflows.

MATERIAL AND METHODS

A patient in need of additive esthetic treatment was examined, and intraoral and extraoral photographs and intraoral digital scans were made, followed by 3D digital smile design using the exocad software program. The reference virtual design was converted into trial restorations (N=40) by using different digital workflows: subtractive manufacturing, additive manufacturing, additive manufacturing of 3D designed index, and silicone index on an additively manufactured cast. Fabricated trial restorations of all groups were scanned with a desktop scanner, providing a standard tessellation language (STL) file serving as the test data for each trial restoration. All the STL files of the test and reference data were imported into a reverse engineering software program to evaluate the 3D trueness of each workflow. Also, analog and digital 2D linear measurements (maxillary left central incisor height, maxillary left central incisor width, and intercanine width) were made to assess any dimensional alterations between the fabricated trial restorations and the reference digital smile design. A 1-way analysis of variance (ANOVA) was used to analyze the data followed by the Tukey post hoc test (α=.05).

RESULTS

For 3D trueness measurements, root mean square (RMS) values representing the deviations between the fabricated trial restorations and the reference digital smile design varied significantly among the different groups (P<.001), with the highest mean deviation found in the group of additive manufacturing of 3D designed index (0.21 ±0.01 mm), while the lowest mean value of deviation was found in the group of subtractive manufacturing (0.11 ±0.02 mm). For both the digital and analog 2D linear measurements, post hoc pairwise comparisons showed the group of additive manufacturing of 3D designed index to have significantly higher values of deviation than the other groups in all assigned measurements (P<.001).

CONCLUSIONS

The accuracy of CAD trial restorations was affected by the fabrication technique, and implementing conventional steps in the digital workflows of trial restoration fabrication may result in discrepancies that affect accuracy when compared with the reference design.

Accuracy of the preparation depth in mixed targeted restorative space type veneers assisted by different guides: An in vitro study

PURPOSE

Most veneers are mixed targeted restorative space (MTRS)-type restorations that are partially within the original tooth and require inconsistent preparation depths. This study aimed to evaluate the accuracy of the preparation depth for MTRS veneer preparation.

METHODS

MTRS veneer preparation models were developed using the twisted maxillary central incisor (MCI) as the original tooth and the standard MCI as the waxing. Veneer preparations were performed using freehand (MF), silicone (MS), thermoplastic (MT), 3D-printed uniform (MD), and auto-stop (MA) guides. The prepared and original MCI were scanned and superimposed using a custom-made base. The mean absolute differences (MADs) were measured to evaluate the accuracy of the preparation depth. Statistical analysis was performed using the multivariate analysis of variance (MANOVA) test (α=0.05).

RESULTS

The accuracy of the preparation depth was 0.237±0.090, 0.191±0.099, 0.149±0.078, 0.093±0.050, and 0.059±0.040 mm in MF, MS, MT, MD, and MA, respectively. The MADs between the groups were significant (P<0.05). The accuracy of the trial restoration was 0.140±0.081 mm in the MS, and the accuracy of the guiding tube was 0.055±0.033, 0.036±0.011, and 0.033±0.010 mm in the MT, MD, and MA, respectively.

CONCLUSIONS

In MTRS veneer preparation for MCI, tooth preparation guides improved the accuracy of the preparation depth by visualizing the TRS profile and providing clear measurement points. The accuracy of the guide is influenced by its flexibility, and the accuracy of the preparation depth is affected by the accuracy of the measurement points.

Application of orthodontics combined with porcelain laminate veneers in the aesthetic restoration and flora regulation of anterior teeth

To evaluate the effectiveness of orthodontics in combination with porcelain laminate veneers (PLV) in the aesthetic restoration and flora regulation of anterior teeth. A retrospective analysis of 336 patients who underwent aesthetic restoration of anterior teeth in our hospital from April 2019 to September 2022 was performed and divided into a control group (n = 168) and an observation group (n = 168) according to the restorative modality. The restorative modality in the control group was conventional restorative remediation, while the restorative modality in the observation group was orthodontic combined with PLV treatment. To evaluate the excellent rate of aesthetic restoration of anterior teeth in the 2 groups, and compare the color, shape, degree of translucency, edge aesthetic score, complications and satisfaction rate of restoration of anterior teeth in the 2 groups before and after restoration. The observation group had a significantly higher rate of excellent aesthetic restorations (95.23%) compared to the control group (80.95%) (P < .001). The scores of anterior tooth color, morphology, degree of translucency and marginal aesthetics were improved in both groups after restoration compared to before restoration, and the scores were significantly higher in the observation group (P < .05). After restoration, the subgingival Digestive streptococcus, Campylobacter and Propionibacterium increased in both groups, but the number of bacterial strains was significantly less in the observation group (P < .05). Compared with the total complication rate in the control group (16.66%), the total complication rate in the observation group (2.38%) was significantly lower (P < .001). Compared with the control group (85.71%), the observation group had a significantly higher restoration satisfaction rate of 97.61%, with a statistically significant difference (P < .001). The application of orthodontics combined with PLV in the aesthetic restoration of anterior teeth has a significant clinical effect, which is conducive to improving the aesthetic restoration and satisfaction rate of anterior teeth, reducing the subgingival microbial imbalance and decreasing the incidence of complications.

Smile Design and Treatment Planning-Conventional versus Digital-A Pilot Study

INTRODUCTION

Several methods are currently available for providing a preview of the prosthodontic treatment, including computer simulations, 3D models, wax-ups, and mock-ups. The aim of this study is to compare the aesthetic aspects and assessment of conventional versus digital prefigurative methods.

METHODS

The study included 5 patients and 3 observers, for each of whom a wax-up was made in both the conventional and digital techniques. The analog method, which implied a mock-up molding with a silicone matrix of the wax-up, was compared to a digital workflow, which consisted of a mock-up milling from a digital design. The patient's clinical mock-ups were recorded with digital photographs and assessed for nine different criteria by three observers.

RESULTS

The analysis has shown a balanced assessment of the aesthetic criteria without any significant difference between the analog and digital prefigurative methods.

CONCLUSIONS

Between the two wax-ups (conventional and digital), there were some variations in smile and dental criteria; however, the obtained data were very similar. When it comes to the smile criteria, the general average grades of the mock-ups conducted using the conventional method are slightly higher than the ones using the digital technique.

Prosthetically Guided Orthodontics (PGO): A Personalized Clinical Approach for Aesthetic Solutions Using Digital Technology

Conformative rehabilitation generally involves the treatment of partial dentate or the application of veneers. In this regard, conformative rehabilitation aims to generate an aesthetic prosthetic solution minimizing the amount of tissue removal without generating occlusal input interfering with the equilibrium of neuro-muscular function. In fact, pre-prosthetic orthodontics aims to re-establishing the correct position/inclination of the neighboring or antagonist teeth, providing appropriate space for the prosthetic crown. Clear aligners therapy (CAT) represents a valuable tool in the management of prosthetic cases with a conformative approach, as it allows clinicians to plan orthodontic movements that are guided by the prosthetic outcomes. In the present manuscript, we argue the concept of prosthetic guided orthodontics (PGO) by presenting and discussing three cases treated with the Invisalign GO system, which has been developed for the clinical management of multidisciplinary orthodontic-prosthetic cases with a conformative approach. In this regard, the rationale of this paper is to address the effectiveness and predictability of the digital set-up and CAT for aesthetic conformative rehabilitations.

Method Presentation of a New Integrated Orthodontic-Conservative Approach for Minimally Invasive Full Mouth Rehabilitation: Speed Up Therapy

The materials available today allow for extensive oral rehabilitations in a non-invasive way, and often an orthodontic preparation is useful and, thanks to the use of clear aligners, is predictable and comfortable. A preliminary study of the wax-up, mock-up, and set-up allow the clinician to plan every aspect of the treatment in detail. Furthermore, the procedure offers the patient an intuitive and understandable view of the expected final result. The new proposed method, called “speed up therapy”, allows for the integration of the orthodontic set-up with the mock-up technique, simulating the occlusal and aesthetic components of the planned restoration, in all details. The clinical case presented, demonstrates step by step the predictability and clinical reliability of the proposed procedure. The final clinical result coincides exactly with the initial mock-up and demonstrates that the proposed method is predictable and reliable. The correct execution of the technique is rigorously customized, and its success is operator dependent, both for the clinical aspects and for the dental laboratory. Thus, the visualization of the objectives of the treatment constitutes a decisive support for the clinician and provides the patient with the possibility of benefiting from an immediate improvement by making it easier for them to accept a treatment plan. The visualization also includes an orthodontic phase that potentially lengthens the treatment but makes the realization more conservative and predictable.

Facial Scanning Accuracy with Stereophotogrammetry and Smartphone Technology in Children: A Systematic Review

The aim of the study was to systematically review and compare the accuracy of smartphone scanners versus stereophotogrammetry technology for facial digitization in children. A systematic literature search strategy of articles published from 1 January 2010 to 30 August 2022 was adopted through a combination of Mesh terms and free text words pooled through boolean operators on the following databases: PubMed, Scopus, Web of Science, Cochrane Library, LILACS, and OpenGrey. Twenty-three articles met the inclusion criteria. Stationary stereophotogrammetry devices showed a mean accuracy that ranged from 0.087 to 0.860 mm, portable stereophotogrammetry scanners from 0.150 to 0.849 mm, and smartphones from 0.460 to 1.400 mm. Regarding the risk of bias assessment, fourteen papers showed an overall low risk, three articles had unclear risk and four articles had high risk. Although smartphones showed less performance on deep and irregular surfaces, all the analyzed devices were sufficiently accurate for clinical application. Internal depth-sensing cameras or external infrared structured-light depth-sensing cameras plugged into smartphones/tablets increased the accuracy. These devices are portable and inexpensive but require greater operator experience and patient compliance for the incremented time of acquisition. Stationary stereophotogrammetry is the gold standard for greater accuracy and shorter acquisition time, avoiding motion artifacts.

A comparison of accuracy between three different facial detection systems for prosthodontic esthetic preview: a single-blinded in vitro study

BACKGROUND

The aim of this study was to compare the accuracy of 3 different devices for facial images acquisition, useful for prosthodontic esthetic preview.

METHODS

Bidimensional extraoral photographs (Nikon D300), facial scans (Bellus3D) and 3D digital stereophotogrammetry photos (3dMD Face System) were acquired from 15 patients. The intraoral impressions of all subjects were digitally taken through a scanner (i500; Medit). Files obtained from each acquisition method were transferred on Exocad Software, and the measurements of the frontal teeth were performed and compared with those of the intraoral scans, assumed as reference. The data were statistically analyzed (Friedman and Dunn tests) with P<0.05.

RESULTS

As for central and lateral incisors, no significant difference emerged between 2D digital photography and intraoral scans, both in height and width. Measures obtained with Bellus3D significantly differed from the reference data in width of all teeth, except for central incisors. Values referred to canines were those more subjected to significant distortions in width for all devices.

CONCLUSIONS

Within the limits of this study, measures of frontal teeth acquired by 2D digital photography were similar to those of intraoral scans both in height and width, while those obtained with 3D facial scanners were more subjected to distortions in mesial-distal dimension.

Electromyographic Activity of Masticatory Muscles in Subjects with Juvenile Idiopathic Arthritis: A Case—Control Study

The aim of this study was to evaluate the effect of juvenile idiopathic arthritis (JIA) on the activity of masticatory muscles using surface electromyography (sEMG). Forty-one JIA subjects (ten males, thirty-one females; average age 13 years ± 3) and thirty-two healthy control subjects (twenty-seven females, five males; average age 14 years ± 2) were recruited. sEMG of anterior temporalis (TA), masseter (MM), and sternocleidomastoid (SCM) muscles was performed by using the occlusal contact analyzer software called Teethan (BTS S.p.A., Garbagnate Milanese, Milan, Italy). Comparisons between groups were assessed with unpaired t-tests for non-normally distributed data and with Mann–Whitney U tests for normally distributed parameters. The JIA group showed a significant increased percentage overlapping coefficient of TA (POC TA) (p = 0.01) and impact index (IMP) (p = 0.003). No significant differences were observed for the POC MM, POC SCM, percentage overlapping coefficient between posterior and anterior teeth contact (BAR), the torsion index (TORS), and the asymmetry index (ASIM). Masticatory muscles seemed to be slightly affected by JIA. sEMG could be an effective aid in the early clinical detection of TMJ involvement in JIA. Further research is needed to confirm its validity.

Digital planning of composite customized veneers using Digital Smile Design: Evaluation of its accuracy and manufacturing

OBJECTIVES

This study aimed to evaluate the production of customized composite veneers starting from a two-dimensional (2D) digital preview using the Digital Smile System (DSS). MATERIAL AND METHODS: A photographic examination of 30 patients was performed by taking two digital pictures of the face and a digital preview through the DSS. Moreover, optical scans of the dental arches were obtained and the data were entered into a three-dimensional (3D) software to prepare a virtual preview. The standard tessellation language files were sent for production using CAD-CAM technology. The Friedman test, Bonferroni, and Dunn post hoc tests were used, comparing the linear measurements of the 2D and 3D plans and the final veneers (α = .05).

RESULTS

Significant differences emerged between the pictures and digital scans on the mesial-distal widths of the lateral incisors and canine. Linear measurements in the 2D plan were significantly different from those of the 3D plan, except for the height measures of incisors. No significant changes were found on comparing the parameters of the 2D and 3D plans with those of the final pieces.

CONCLUSIONS

The customized veneers were clinically adequate and similar to 2D and 3D plans, although significant differences emerged between the picture and digital scans as well as between the 2D and 3D plans.

Teleorthodontics: Where Are We Going? From Skepticism to the Clinical Applications of a New Medical Communication and Management System

Teleorthodontics represents the orthodontic care system involving remote management of orthodontic treatment. Despite skepticism, there are several advantages of including teleorthodontics in the clinical orthodontic practice. In the present review, we discuss the lights and shadows of this new communication healthcare system and its applications in the field of orthodontics that is destined to change the future of our clinical practice. For this purpose, we have provided a point-to-point analysis based on data from the most valuable scientific evidence on this topic. The information and data discussed in the present paper were obtained from the most relevant studies evaluating the performance of teleorthodontics and remote monitoring systems in clinical practice.

Orthodontics Surgical Assistance (Piezosurgery®): Experimental Evidence According to Clinical Results

Orthodontic tooth movement (OTM) is based on intermitted or continuous forces applied to teeth, changing the mechanical loading of the system and arousing a cellular response that leads to bone adaptation. The traditional orthodontic movement causes a remodeling of the alveolar bone and changes in the periodontal structures that lead to tooth movement. The use of a piezoelectric instrument in orthodontic surgery has already shown great advantages. The purpose of this study is to rank the behavior of inflammatory mediators in accelerating orthodontic tooth movement. Ten patients with malocclusion underwent orthodontic surgical treatment, which included a first stage of surgically guided orthodontic movement (monocortical tooth dislocation and ligament distraction, MTDLD) to accelerate orthodontic movements. In all cases, corticotomy was performed by Piezosurgery. Bone and dental biopsy was executed to evaluate changes in the cytokines IL-1beta, TNF-alpha and IL-2 in different time intervals (1, 2, 7, 14 and 28 days). The molecular mediators are IL-1 beta, TNF-alpha and IL-2. Immediately after the surgical procedure there was a mild expression of the three molecular markers, while the assertion of IL-1 beta and TNF-alpha reached the maximum value after 24 h and 48 h, indicating a strong activation of the treated tissues. The Piezosurgery® surgical technique induces an evident stress in short times, within 24–48 h from the treatment, but it decreases significantly during the follow-up.

Mechanical Behaviour and Primary Stability of a Self-Condensing Implant: A Laboratory Critical Simulation of a Severe Maxillary Atrophy on Polyurethane Lamina

Background: Posterior maxillary atrophies could emerge after the loss of teeth, trauma, infections, or lesions that often require regenerative approaches. In these critical conditions, the achievement of implant primary stability represents a clinical challenge in the operative practice. Therefore, a two-stage approach is often preferred with a delay of the rehabilitation time and a consistent increasing of the biological and the operative costs. The aim of this study was to evaluate the mechanical behaviour of a self-condenser implant compared to a standard implant in a critical simulation on different thicknesses and densities of polyurethane lamina. Materials and methods: A total of two implant models were tested: a self-condensing device (test) and a standard implant (control). The study evaluated the insertion torque and the pull-out strength values of the test and control implants inserted in different sizes (1, 2, and 3 mm) and density polyurethane lamina (10, 20, and 30 pcf) for a total of 320 experimental sites. Results: In total, 320 experimental sites were produced in the polyurethane samples. A statistically significant difference of insertion and pull-out torque values between the test and control Implants was found in the different bone densities (p < 0.05). The insertion and pull-out torque values were always higher for the test implants in all experimental conditions. In all bone densities, the insertion torque values were higher than the pull-out torque values. The self-condenser dental implant design evaluated in this in vitro study showed a high level of stability in all experimental conditions. Conclusions: The test implant could represent a useful tool for a one-stage surgical approach in the presence of limited residual native bone as an alternative to a delayed technique.

Evaluation of the accuracy of orthodontic models prototyped with entry-level LCD-based 3D printers: a study using surface-based superimposition and deviation analysis

OBJECTIVES

The objective of this study was to evaluate the accuracy of dental models prototyped via entry-level liquid crystal display (LCD) 3D printers.

MATERIALS AND METHODS

Identical prototyped models were generated from a master digital file testing two entry-level LCD-based 3D printers and using one professional-grade 3D printer as gold standard (GS), with 50-µm and 100-µm layer thickness. Each 3D-printed model was scanned, and a specific 3D technology was used to perform surface-based superimposition and deviation analysis to evaluate trueness and precision. The distances between surface points of two superimposed models were converted to root mean square (RMS) and statistically analyzed.

RESULTS

The RMS values detected were significantly higher in dental models prototyped with entry-level compared to the SLA printer (p < 0.001), in terms of trueness (50 µm: GS 0.075 mm, LCD1 0.192 mm, LCD2 0.179 mm; 100 µm: GS 0.066 mm, LCD1 0.209 mm, LCD2 0.199 mm) and precision (50 µm: GS 0.028 mm, LCD1 0.075 mm, LCD2 0.085 mm; 100 µm: GS 0.039 mm, LCD1 0.096 mm, LCD2 0.101 mm). No significant differences were found between the values of RMS of both entry-level 3D printers (p > 0.05). Layer thickness did not affect either the trueness or precision of the 3D-printed models (p > 0.05).

CONCLUSION

Entry-level LCD-based 3D printers are not as accurate as professional-grade 3D printer, but still close to orthodontics clinical threshold values.

CLINICAL RELEVANCE

Clinicians should evaluate the intended application of 3D-printed orthodontic models before using entry-level 3D printers.

Etiological Factors of the Midline Diastema in Children: A Systematic Review

BACKGROUND

Midline diastema in children is a prevalent developmental entity, and this pathological condition may remain in many children due to various factors. Nonetheless, the evidence on etiological factors of the midline diastema in children is minimal.

PURPOSE

To evaluate the etiological factors of midline diastema causes in children below 12 years of age from the published data.

METHODS

A literature search was confined to the English language using MeSH terms conferring to PICO format in PubMed, Cochrane Library, and Ovidsp covering the period from January 1960 to December 2019. Search in Google Scholar, grey literature, and hand search on references were performed to find additional data. Suitable studies were selected based on the predefined inclusion and exclusion criteria. Quality analysis of the chosen studies conducted using the Newcastle-Ottawa Scale (NOS) adapted for cross-sectional studies.

RESULTS

Only eight studies were available for final analysis among those four studies from India, two studies from Korea, one study from Brazil, and another study from Canada. The most common etiology for midline diastema was supernumerary teeth followed by morphology labial frenum and nasal airflow condensation. The quality analysis of these studies based on NOS showed one study with unsatisfactory, four studies with satisfactory, and three with good quality.

CONCLUSION

Morphology of frenum, pre-maxillary supernumerary teeth, and nasal airflow condensation seem to be the most common causes of midline diastema in children below 12 years.

Comparison between Additive and Subtractive CAD-CAM Technique to Produce Orthognathic Surgical Splints: A Personalized Approach

The present study aimed to evaluate the accuracy of digitally designed surgical splints generated with milling technology (material subtractive procedure) and with 3D printing technology (material additive procedure) through a customized approach in the planning of surgical orthognathic splints. Cone beam computed tomography (CBCT) examinations and scanned dental models of 10 subjects who had required surgical treatment of skeletal malocclusion were included. Simulation of the orthognathic surgery was performed according to dento-skeletal and aesthetic characteristics of the subjects and the visual treatment objective (VTO), using Dolphin3D software (Dolphin Imaging, version 11.0, Chatsworth, CA, USA). Afterward, the Appliance Designer software (3Shape A/S, Copenhagen, Denmark) was used to digitally design the surgical splints that were generated twice using laser stereolithography technology (DWS 0.29D, DWS, Vicenza, Italy) and milling technology (Sirona inLab MC X5). Finally, each physical splint was digitalized using a desktop scanner (D500 3D, 3Shape A/S, Copenhagen, Denmark) in order to perform deviation analysis using the original project as a reference. The relative percentage of matching (trueness) was calculated (Geomagic Control X software (3D Systems, version 2018.1.1, 3D Systems, Rock Hill, SC, USA). An Independent Student's t-test was used to statistically analyze the data. The milled splints showed a lower value of root to mean square (RMS) relative to the original project (0.20 mm ± 0.018) compared to the prototyped splints (0.31 ± 0.021) (p < 0.001). According to the present findings, surgical splints generated with milling technology present higher trueness compared with 3D printing technology.

Perception of Smile Aesthetics of Patients with Anterior Malocclusions and Lips Influence: A Comparison of Dental Professionals’, Dental Students,’ and Laypersons’ Opinions

Objectives. The aim of the study was to evaluate the perception of smile aesthetics in patients with varying degrees of anterior crowding and spacing among dental specialists, dentists, dental students, and laypersons and to assess the effect of the lips position. Materials and Methods. Clinical photos of cases of anterior crowding (mild, moderate, and severe) and spacing (mild, moderate, and severe) with and without the associated lips were used. The images were evaluated by 250 persons including dental specialists, dentists, dental students, and laypersons using the rating scale method, (extremely unaesthetic to extremely aesthetic, 1 to 5, respectively). Nonparametric tests were used to analyse the data on SPSS version 24. Results. According to the 250 responses, the aesthetic perception of all severities of anterior crowding and mild and moderate spacing was found to be more aesthetic when displayed with the lips ( $p<0.05$ ). Additionally, the higher the level of dental education, the lower the aesthetic perception with and without the lips ( $p<0.05$ ). Conclusions. The lips play a significant role in improving the aesthetics of crowded anterior teeth and spaced anterior teeth. Dental educational level influences the aesthetic perception of anterior crowding and spacing. This may have an impact on treatment planning and need for orthodontic intervention.

The Impact of Diet, Nutrition and Nutraceuticals on Oral and Periodontal Health

Oral and periodontal diseases can determine severe functional, phonatory and aesthetic impairments and are the main cause of adult tooth loss. They are caused by some specific bacteria that provoke an intense local inflammatory response and affect-with particular gravity-susceptible subjects, because of reasons related to genetics and lifestyles (e.g., smoking and home oral hygiene habits). They are more frequent in the disadvantaged segments of society and, in particular, in subjects who have difficulty accessing preventive services and dental care. Some systemic diseases, such as uncontrolled diabetes, can increase their risk of development and progression. Recently, in addition to the obvious considerations of severe alterations and impairments for oral health and well-being, it has been noted that periodontitis can cause changes in the whole organism. Numerous clinical and experimental studies have highlighted the presence of a strong association between periodontitis and some systemic diseases, in particular, cardiovascular diseases, diabetes, lung diseases and complications of pregnancy. The purpose of this editorial is to provide a current and thoughtful perspective on the relationship of diet and natural agents on oral, periodontal diseases, and chewing disorder preventions which may reflect good systemic conditions and related quality of life or to analyze indirect effects through the contribution of diet and nutrition to systemic health in order to obtain a modern diagnostic-therapeutic approach.

Comparison of Mandibular Arch Expansion by the Schwartz Appliance Using Two Activation Protocols: A Preliminary Retrospective Clinical Study

BACKGROUND AND OBJECTIVES

Dental crowding is more pronounced in the mandible than in the maxilla. When exceeding a significant amount, the creation of new space is required. The mandibular expansion devices prove to be useful even if the increase in the lower arch perimeter seems to be just ascribed to the vestibular inclination of teeth. The aim of the study was to compare two activation protocols of the Schwartz appliance in terms of effectiveness, particularly with regard to how quickly crowding is solved and how smaller is the increasing of vestibular inclination of the mandibular molars.

MATERIALS AND METHODS

We compared two groups of patients treated with different activation's protocols of the lower Schwartz appliance (Group 1 protocol consisted in turning the expansion screw half a turn twice every two weeks and replacing the device every four months; Group 2 was treated by using the classic activation protocol-1/4 turn every week, never replacing the device). The measurements of parameters such as intercanine distance (IC), interpremolar distance (IPM), intermolar distance (IM), arch perimeter(AP), curve of Wilson (COW), and crowding (CR) were made on dental casts at the beginning and at the end of the treatment.

RESULTS

A significant difference between protocol groups was observed in the variation of COWL between time 0 and time 1 with protocol 1 with protocol 1 subjects showing a smaller increase in the parameter than protocol 2 subjects. The same trend was observed also for COWR, but the difference between protocol groups was slightly smaller and the interaction protocol-by-time did not reach the statistical significance. Finally, treatment duration in protocol 1 was significantly lower than in protocol 2.

CONCLUSION

The results of our study suggest that the new activation protocol would seem more effective as it allows to achieve the objective of the therapy more quickly, and likely leading to greater bodily expansion.

Oral Health and Related Factors Associated with General Health and Quality of Life

Oral well-being is an integral part of individual general health. The mouth and teeth are, in fact, part of our body, increasingly characterizing personal identity. Oral diseases are a public health problem that has a growing prevalence. Oral pathologies can occur in childhood, and as they have a chronic and progressive course, if not properly treated, they can affect the relational, psychological, and social skills of an individual. The population most affected are those with a low socio-economic level, so much so that the presence of diseases of the oral cavity is considered a marker of social disadvantage. In this regard, much effort is needed from scientists, and their applied sciences, in order to give the knowledge required for public health personal to take note of the seriousness of the situation and to start changing the way we deal with the problem.

Evaluation of Imaging Software Accuracy for 3-Dimensional Analysis of the Mandibular Condyle. A Comparative Study Using a Surface-to-Surface Matching Technique

The aim of this study was to assess the accuracy of 3D rendering of the mandibular condylar region obtained from different semi-automatic segmentation methodology. A total of 10 Cone beam computed tomography (CBCT) were selected to perform semi-automatic segmentation of the condyles by using three free-source software (Invesalius, version 3.0.0, Centro de Tecnologia da Informação Renato Archer, Campinas, SP, Brazil; ITK-Snap, version2.2.0; Slicer 3D, version 4.10.2) and one commercially available software Dolphin 3D (Dolphin Imaging, version 11.0, Chatsworth, CA, USA). The same models were also manually segmented (Mimics, version 17.01, Materialise, Leuven, Belgium) and set as ground truth. The accuracy of semi-automatic segmentation was evaluated by (1) comparing the volume of each semi-automatic 3D rendered condylar model with that obtained with manual segmentation, (2) deviation analysis of each 3D rendered mandibular models with those obtained from manual segmentation. No significant differences were found in the volumetric dimensions of the condylar models among the tested software (p > 0.05). However, the color-coded map showed underestimation of the condylar models obtained with ITK-Snap and Slicer 3D, and overestimation with Dolphin 3D and Invesalius. Excellent reliability was found for both intra-observer and inter-observer readings. Despite the excellent reliability, the present findings suggest that data of condylar morphology obtained with semi-automatic segmentation should be taken with caution when an accurate definition of condylar boundaries is required.

Implant-Supported Prosthetic Therapy of an Edentulous Patient: Clinical and Technical Aspects

The purpose of this article is to show how to implement an implant-supported prosthetic overdenture using a digital workflow. Esthetic previewing using a specific software, guided-surgery, construction of the prosthesis, and the esthetic finalization are described in this article. Patients suffering from severe loss of bone and soft tissue volume could benefit from the construction of an overdenture prosthesis as a feasible therapeutic choice for functional and esthetic issues of the patient.

One Step before 3D Printing-Evaluation of Imaging Software Accuracy for 3-Dimensional Analysis of the Mandible: A Comparative Study Using a Surface-to-Surface Matching Technique

The accuracy of 3D reconstructions of the craniomaxillofacial region using cone beam computed tomography (CBCT) is important for the morphological evaluation of specific anatomical structures. Moreover, an accurate segmentation process is fundamental for the physical reconstruction of the anatomy (3D printing) when a preliminary simulation of the therapy is required. In this regard, the objective of this study is to evaluate the accuracy of four different types of software for the semiautomatic segmentation of the mandibular jaw compared to manual segmentation, used as a gold standard. Twenty cone beam computed tomography (CBCT) with a manual approach (Mimics) and a semi-automatic approach (Invesalius, ITK-Snap, Dolphin 3D, Slicer 3D) were selected for the segmentation of the mandible in the present study. The accuracy of semi-automatic segmentation was evaluated: (1) by comparing the mandibular volumes obtained with semi-automatic 3D rendering and manual segmentation and (2) by deviation analysis between the two mandibular models. An analysis of variance (ANOVA) was used to evaluate differences in mandibular volumetric recordings and for a deviation analysis among the different software types used. Linear regression was also performed between manual and semi-automatic methods. No significant differences were found in the total volumes among the obtained 3D mandibular models (Mimics = 40.85 cm³, ITK-Snap = 40.81 cm³, Invesalius = 40.04 cm³, Dolphin 3D = 42.03 cm³, Slicer 3D = 40.58 cm³). High correlations were found between the semi-automatic segmentation and manual segmentation approach, with R coefficients ranging from 0,960 to 0,992. According to the deviation analysis, the mandibular models obtained with ITK-Snap showed the highest matching percentage (Tolerance A = 88.44%, Tolerance B = 97.30%), while those obtained with Dolphin 3D showed the lowest matching percentage (Tolerance A = 60.01%, Tolerance B = 87.76%) (p < 0.05). Colour-coded maps showed that the area of greatest mismatch between semi-automatic and manual segmentation was the condylar region and the region proximate to the dental roots. Despite the fact that the semi-automatic segmentation of the mandible showed, in general, high reliability and high correlation with the manual segmentation, caution should be taken when evaluating the morphological and dimensional characteristics of the condyles either on CBCT-derived digital models or physical models (3D printing).

Craniomandibular Disorders in Pregnant Women: An Epidemiological Survey

Temporomandibular joint (TMJ) disorder has been reported to be 1.5 to two times more common in women than men. Such a gender-based difference could be attributed to behavioral, hormonal, anatomical, and psychological characteristics. Physiological hormonal differences between genders could be one of the possible explanations for the higher incidence of temporomandibular disorder (TMD) in women. As the plasma level of certain female hormones increases during gestation, it could be assumed that there is a higher prevalence of dysfunctional signs and symptoms in pregnant women. We performed an epidemiological survey based on screening for TMD in a group of 108 pregnant women and found that 72% of young women reported significant signs of TMJ disorders, 9% of the young women reported mild signs of TMJ disorders, and 19% of the included subjects reported no signs or symptoms of TMD. The presence of estrogen receptors in the temporomandibular joint of female baboons could be the basis of an explanation for the increased prevalence of dysfunction in young women reported in the literature and the high feedback we have seen of joint noises in pregnant women. On the basis of the present findings, it could be assumed that gestation period could represent a risk factor for craniomandibular dysfunctions.