Pros and Cons of CAD/CAM Technology for Infection Prevention in Dental Settings during COVID-19 Outbreak.

The purpose of this commentary is to update the evidence reported in our previous review on the advantages and limitations of computer-aided design/computer-aided manufacturing technology in the promotion of dental business, as well as to guarantee patient and occupational safety. The COVID-19 pandemic led to an unprecedented focus on infection prevention; however, waves of COVID-19 follow one another, asymptomatic cases are nearly impossible to identify by triage in a dental setting, and the effectiveness of long-lasting immune protection through vaccination remains largely unknown. Different national laws and international guidelines (mainly USA-CDC, ECDC) have often brought about dissimilar awareness and operational choices, and in general, there has been very limited attention to this technology. Here, we discuss its advantages and limitations in light of: (a) presence of SARS-CoV-2 in the oral cavity, saliva, and dental biofilm and activation of dormant microbial infections; (b) the prevention of SARS-CoV-2 transmission by aerosol and fomite contamination; (c) the detection of various oral manifestations of COVID-19; (d) specific information for the reprocessing of the scanner tip and the ward from the manufacturers.

Computer-Aided Design and Computer-Aided Manufacturing Versus Conventional Free Fibula Flap Reconstruction in Benign Mandibular Lesions: An Italian Cost Analysis.

PURPOSE: The cost of computer-aided design and computer-aided manufacturing (CAD-CAM) technology has created obstacles for its widespread use despite its several advantages. This study compared the cost of CAD-CAM technology with that of the conventional freehand technique in fibula reshaping for mandibular reconstruction. MATERIALS AND METHODS: A retrospective comparative study was conducted at the Maxillofacial and Dental Unit of the Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico (Milan, Italy). The study compared 15 patients in the CAD-CAM group with 10 patients in the conventional freehand group. Only benign pathologic lesions that required at least 3 fibular segments for reconstruction were included. The consumption of resources was estimated using micro-costing analysis (activity-based costing approach). RESULTS: The CAD-CAM group included 15 patients (7 men and 8 women) with a mean age of 42.2 ± 1.5 years, and the conventional freehand group included 10 patients (4 men and 6 women) with a mean age of 40.8 ± 0.9 years. Although CAD-CAM was a statistically expensive procedure in the perioperative phase (P < .0001), no significant difference was shown in total health care costs between the 2 groups (P = .98). CONCLUSION: CAD-CAM technology had a comparable expense to the conventional freehand technique, specifically for defects requiring at least 3 fibular segments.

The Effect of Orthognathic Surgery on Soft-Tissue Facial Asymmetry: A Longitudinal Three-Dimensional Analysis.

In modern orthognathic surgery, the functional results cannot disregard a good aesthetic outcome. In this study, a stereophotogrammetric longitudinal analysis of the symmetry of facial thirds was performed in 18 patients affected by Class III skeletal malocclusion, with clinical asymmetry, treated with a bimaxillary osteotomy. Their 3-dimensional facial images were acquired in the preoperative phase and 6, 12, and 24 months after surgery, and compared to those obtained in a control group of 23 subjects with Class I skeletal occlusion, without clinical asymmetry and no history of traumas or alterations at the maxillo-facial area. Images of the hemi-faces of the subjects were divided into thirds (upper, middle, lower), mirrored and superimposed to their contralateral ones; soft-tissue facial symmetry was obtained as the root mean square distance between the hemi-faces in the three thirds.In patients, no significant differences in facial symmetry (root mean square distance) were found among the study time points (analysis of variance, P > 0.05); the lower facial third was more asymmetric than the upper one (Tukey honestly significant difference P < 0.05). Patients were significantly more asymmetric than the control subjects (Student t, P < 0.05). In conclusion, patients with Class III malocclusion exhibited a higher level of facial asymmetry than control subjects; their asymmetry did not change significantly in the different phases of the surgical and orthodontic treatment and throughout a 24-month follow-up. In skeletal Class III patients, bimaxillary osteotomy did not modify the level of asymmetry in any facial third.

Donor-Site Morbidity After Osteocutaneous Free Fibula Transfer: Longitudinal Analysis of Gait Performance.

PURPOSE: The purpose was to evaluate donor-site clinical morbidity and changes in kinematic gait parameters after the harvest of a vascularized free fibula flap for facial reconstruction. MATERIALS AND METHODS: We enrolled 14 patients (aged 50 ± 15 years) in a longitudinal study. Every patient underwent a double evaluation in which a presurgical assessment and 6-month postsurgical assessment were performed. Subjective donor-site evaluation was carried out through unstructured clinical questioning about pain, paresthesia, walking ability, and restrictions in activity. Further subjective evaluations were assessed through the Western Ontario and McMaster Universities Osteoarthritis Index and the Point Evaluation System for Lower Extremity Fibulectomy. A clinical evaluation of the donor site assessed muscular deficits, sensibility disturbance, and wound healing. Temporal and spatial kinematic parameters were measured through gait analysis during overground walking at a comfortable speed. RESULTS: Postsurgical clinical examinations detected 1 patient affected by a neurologic disorder and 3 patients with donor-site pain, whereas 10 patients (71%) declared no residual alterations in the operated leg. On average, the Western Ontario and McMaster Universities Osteoarthritis Index score was 367 of 2,400, and the Point Evaluation System for Lower Extremity Fibulectomy score was 19 of 24. Presurgical versus postsurgical gait analysis comparison showed no significant differences in gait parameters except for a 6% reduction in the double-support phase. Stance values were higher for the operated limb in both evaluations (+1.3% before surgery, +1.8% after surgery). No alterations were detected in the range of motion of the lower-limb joints. CONCLUSIONS: Considering the slight modification of the gait pattern, which is not usually perceived by patients, vascularized free fibula flap harvest was generally associated with successful functional and subjective outcomes of the donor site.

Evaluation of the Accuracy of Virtual Planning in Orthognathic Surgery: A Morphometric Study.

BACKGROUND: The purpose of this study was to prospectively test the accuracy of computer-aided orthognathic surgery comparing the virtual surgical planning with the three-dimensional (3D) outcome. METHODS: Patients that underwent computer-assisted orthognathic surgery were retrospectively evaluated. The postoperative results were compared with the surgical plan, superimposing the postoperative computed tomography (CT) scan onto the virtual plan. Surface-based superimpositioning of the postoperative CT scan onto the 3D preoperative plan was carried out to visualize the discrepancy between preoperative virtual plan and postoperative 3D CT result. RESULTS: A total of 17 consecutive patients that underwent two-jaw computer-assisted orthognathic surgery were enrolled in the study.The average linear differences for selected points were <1 mm in 12 patients out of 17. In 5 patients out of 17, the average differences for selected points were <2 mm. CONCLUSIONS: An overall high degree of accuracy between the virtual plan and the postoperative result was found.

Three-Dimensional Stereophotogrammetric Evaluation of the Efficacy of Autologous Fat Grafting in the Treatment of Parry-Romberg Syndrome.

Autologous fat grafting is a surgical procedure used to correct volumetric defects, atrophies, and sclerosis. Three-dimensional (3D) facial photography may enable researchers to quantify the success of surgical procedures through volumetric and surface assessments. Using 3D photography, the authors assessed the results of autologous fat grafting performed in a 15-year-old patient affected by Parry-Romberg syndrome, a rare condition resulting in progressive hemifacial atrophy of skin, subcutaneous tissues and, ultimately, bone. Stereophotogrammetric acquisitions were performed before and 4 months after the surgical intervention. The obtained results were objectively assessed in terms of facial symmetry through calculation of root mean square deviation point-to-point distance between the treated and healthy side, and volume modifications between pre- and postsurgical 3D facial scans. Four months after surgery, 73% of injected adipose tissue was resorbed, whereas facial symmetry increased up to 63%. The proposed method is not invasive and provides quantitative information about the surgical and esthetic outcomes. Clinicians could better plan surgery, and the patients could be more motivated and compliant to the treatment.

Oral Surgery in Patients With Glanzmann Thrombasthenia: A Case Series.

Glanzmann thrombasthenia is a severe defect of platelet function caused by an inherited deficiency or dysfunction of the glycoprotein IIb/IIIa complex, the platelet fibrinogen receptor. Patients with Glanzmann thrombasthenia experience lifelong spontaneous and post-traumatic mucocutaneous bleeding diathesis. Surgery is usually very challenging, requiring close cooperation among surgeons, hematologists, and anesthesiologists. For anatomic reasons, oral surgery is particularly difficult owing to the inherent risk of hemorrhage and the difficulty in achieving local hemostasis. In the present report, we describe 3 successful cases of oral surgery in patients with Glanzmann thrombasthenia and report the surgical and hematologic management of each case.

Resorbable Materials for Reconstruction of the Orbital Floor in Children.

The best treatment of pediatric orbital fractures is debated and different strategies are proposed in the literature. Resorbable materials, due to their features and the specific requirements of the pediatric population, seem a very suitable choice. The authors present their experience by describing 3 cases and explaining their mesh modeling technique. Two fractures were caused by accidental falls, whereas the other resulted from aggression. Clinical and radiological evaluation (computed tomography scanning) was performed before surgery. No complications occurred either immediately after surgery or in the long term (maximum follow-up of 3 y). As there has been little experience of the use of resorbable mesh in maxillofacial pediatric traumatology, the authors describe their technique, which may facilitate the use of this material in orbital fractures.

Stair ascent and descent in assessing donor-site morbidity following osteocutaneous free fibula transfer: a preliminary study.

PURPOSE: The aim of this study was to investigate gait kinematic parameters during stair ascent and descent after fibula free flap removal for facial reconstruction. MATERIALS AND METHODS: Eight patients who underwent facial reconstruction with fibula free flap removal ascended and descended 3 standard steps. Their movements were recorded by a motion analyzer; gait kinematic parameters were obtained and compared with those calculated in 8 control subjects. RESULTS: Stride time, percentage of swing, and support phases did not differ among healthy and operated limbs and control subjects (Kruskal-Wallis, P > .05). No significant differences were found for hip and knee movements, pelvis rotation and tilt, and body center of mass displacements. During stair descent, the patients had significantly larger pelvis inclinations than the control subjects (P < .05). CONCLUSIONS: No functional limitations during stair performance were found. The only significant difference could indicate a minor control of the pelvis and should be used to define specific rehabilitative interventions.

Regeneration of Critical-Sized Mandibular Defects Using 3D-Printed Composite Scaffolds: A Quantitative Evaluation of New Bone Formation in In Vivo Studies.

Mandibular tissue engineering aims to develop synthetic substitutes for the regeneration of critical size defects (CSD) caused by a variety of events, including tumor surgery and post-traumatic resections. Currently, the gold standard clinical treatment of mandibular resections (i.e., autologous fibular flap) has many drawbacks, driving research efforts toward scaffold design and fabrication by additive manufacturing (AM) techniques. Once implanted, the scaffold acts as a support for native tissue and facilitates processes that contribute to its regeneration, such as cells infiltration, matrix deposition and angiogenesis. However, to fulfil these functions, scaffolds must provide bioactivity by mimicking natural properties of the mandible in terms of structure, composition and mechanical behavior. This review aims to present the state of the art of scaffolds made with AM techniques that are specifically employed in mandibular tissue engineering applications. Biomaterials chemical composition and scaffold structural properties are deeply discussed, along with strategies to promote osteogenesis (i.e., delivery of biomolecules, incorporation of stem cells, and approaches to induce vascularization in the constructs). Finally, a comparison of in vivo studies is made by taking into consideration the amount of new bone formation (NB), the CSD dimensions, and the animal model.

Significant association between FGFR1 mutation frequency and age in central giant cell granuloma.

Central giant cell granulomas (CGCG) are rare intraosseous osteolytic lesions of uncertain aetiology. Despite the benign nature of this neoplasia, the lesions can rapidly grow and become large, painful, invasive, and destructive. The identification of molecular drivers could help in the selection of targeted therapies for specific cases. TRPV4, KRAS and FGFR1 mutations have been associated with these lesions but no correlation between the mutations and patient features was observed so far. In this study, we analysed 17 CGCG cases of an Italian cohort and identified an interesting and significant (p=0.0021) correlation between FGFR1 mutations and age. In detail, FGFR1 mutations were observed frequently and exclusively in CGCG from young (<18 years old) patients (4/5 lesions, 80%). Furthermore, the combination between ours and previously published data confirmed a significant difference in the frequency of FGFR1 mutations in CGCG from patients younger than 18 years at the time of diagnosis (9/23 lesions, 39%) when compared to older patients (1/31 lesions, 0.03%; p=0.0011), thus corroborating our observation in a cohort of 54 patients. FGFR1 variants in young CGCG patients could favour fast lesion growth, implying that they seek medical attention earlier. Our observation might help prioritise candidates for FGFR1 testing, thus opening treatment options with FGFR inhibitors.

Medication-Related Osteonecrosis of the Jaw in Dental Practice: A Retrospective Analysis of Data from the Milan Cohort.

A retrospective analysis was performed with the aim of understanding whether the risk factors showed in the literature for medication-related osteonecrosis of the jaws (MRONJ) in cancer patients are also relevant in osteoporotic patients taking antiresorptive drugs (ARDs). Data were retrospectively pooled from health records of patients on ARDs who requested a dental visit between January 2006 and April 2020 in the Dental Unit at Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico, University of Milan. A total of 434 patients were included. The following variables were collected: sex, age, smoking habit, type of ARD, duration of treatment, route of administration, therapeutic indication, concurrent systemic therapies and pathologies. Statistical analysis confirmed the relevance of chemotherapy, smoking, and immunosuppressive drugs as risk factors. In addition, a higher frequency of MRONJ in osteoporotic patients was reported in our cohort in association with an immunodeficiency disorder of variable origin. In conclusion, the identification of individual risk-profile before dental treatments is crucial for prevention. Anamnesis should include main risk factors, such as immunosuppression, dental extractions, smoking, trauma, and poor dental health. Nevertheless, our suggestion for dental professionals is to conduct a complete medical history of patients who mention long-term per oral therapies with ARDs for osteoporosis. Osteoporotic, as well as cancer patients, may also benefit from periodic monitoring of the ARDs therapy in order to prevent MRONJ.

Effects on Muscular Activity after Surgically Assisted Rapid Palatal Expansion: A Prospective Observational Study.

The study aims to investigate the modifications in the temporalis and the masseter activity in adult patients before and after SARPE (Surgically Assisted Rapid Palatal Expansion) by measuring electromyographic and electrokinesographic activity. 24 adult patients with unilateral posterior crossbite on the right side were selected from the Orthodontic Department of the University of Milan. Three electromyographic and electrokinesographic surface readings were taken respectively before surgery (T0) and 8 months after surgery (T1). The electromyographic data of both right and left masseter and anterior temporalis muscles were recorded during multiple tests: standardized maximum voluntary contraction (MVC)s, after transcutaneous electrical nerve stimulation (TENS) and at rest. T0 and T1 values were compared with paired Student's t-test (p < 0.05). Results: Significant differences were found in the activity of right masseter (p = 0.03) and right temporalis (p = 0.02) during clench, in the evaluation of right masseter at rest (p = 0.03), also the muscular activity of masseters at rest after TENS from T0 to T1 (pr = 0.04, pl = 0.04). No significant differences were found in the activity of left masseter (p = 0.41) and left temporalis (p = 0.39) during clench and MVC, in the evaluation of left masseter at rest (p = 0.57) and in the activity during MVC of right masseter (p = 0.41), left masseter (p = 0.34), right temporalis (p = 0.51) and left temporalis (p = 0.77). Results showed that the activity of the masseter and temporalis muscles increased significantly after SARPE during rest and clenching on the side where the cross-bite was treated.

Post-Operative Patients' Satisfaction and Quality of Life Assessment in Adult Patients with Obstructive Sleep Apnea Syndrome (OSAS).

BACKGROUND: The treatment for severe OSAS includes maxillomandibular advancement surgical option in selected cases. The aim of this study was to evaluate the post-operative impact of bimaxillary surgery on satisfaction and consequently the quality of life of these patients. METHODS: This study included 18 patients with severe OSAS who received maxillomandibular advancement surgery. Patients were divided into Group A (operated by CAD/CAM) and Group B (conventional surgery). The impact of bimaxillary surgery on satisfaction and quality of life of these patients was evaluated by utilizing post-operative life quality and Rustemeyer's patient-satisfaction-based survey. RESULTS: A total of 18 adult OSAS patients (Group A: 11 patients, Group B: 7 patients) with a mean age of 44.39 years (SD ± 9.43) were included. Mean follow-up period was 32.64 months (SD ± 21.91). No intra-operative complications were seen in any patients. Post-operative complication was seen in one patient and the mandible did not integrate. According to the results, overall post-operative satisfaction score was 79.72% (SD ± 9.96). There was no significant difference among those in Group A and Group B. CONCLUSIONS: Maxillomandibular advancement surgery seems to be beneficial in terms of patients' satisfaction in severe adult OSAS patients and can be considered as a valuable option in selected cases.