Italian position paper (SIPMO-SICMF) on medication-related osteonecrosis of the jaw (MRONJ).

OBJECTIVE: This paper aims to describe the 2023 update position paper on MRONJ developed by the Italian Societies of Oral Pathology and Medicine (SIPMO) and of Maxillofacial Surgery (SICMF). METHODS: This is the second update following the 2013 and 2020 Italian position papers by the Expert panel, which is a representation of the two scientific societies (SIPMO and SICMF). The paper is based on an extensive analysis of the available literature from January 2003 to February 2020, and the subsequent review of literature conducted between March 2020 and December 2022 to include all new relevant published papers to confirm or modify the previous set of recommendations. RESULTS: This position paper highlights the main issues of MRONJ on risk estimates, disease definition, diagnostic pathway, individual risk assessment, and the fundamental role of imaging in the diagnosis, classification, and management of MRONJ. CONCLUSION: The Expert Panel confirmed the MRONJ definition, the diagnostic work-up, the clinical-radiological staging system and the prophylactic drug holiday, as recognized by SIPMO-SICMF; while, it presented novel indications regarding the categories at risk of MRONJ, the prevention strategies, and the treatment strategies associated with the therapeutic drug holiday.

Physical therapy in addition to occlusal splint in myogenic temporomandibular disorders: A randomised controlled trial.

BACKGROUND: Myogenic temporomandibular disorders (M-TMD) commonly involve occlusal splint (OS) therapy and musculoskeletal physiotherapy (MPT). OBJECTIVES: To compare the effects of combining OS with MPT and education (EG) against OS and education (CG), in chronic M-TMD patients. METHODS: In this double-blind randomised controlled trial, 62 participants were assigned to either EG or CG. The primary outcomes, pain levels at rest (VAS rest), maximum oral opening (VAS open) and during chewing (VAS chew), were measured by Visual Analogue Scale (VAS) in cm. The secondary outcome was the range of motion (ROM) for maximum oral opening. Both interventions lasted 3 months, with outcomes assessed at baseline (T0), post-treatment (T1) and 3 months post-treatment (T2). RESULTS: Intention-to-treat analysis revealed significant improvements favouring EG (VAS rest = -1.50 cm [CI95%: -2.67, -0.32], p = .04; VAS open = -2.00 cm [CI95%: -3.23, -0.75], p < .01; VAS chew = -1.71 cm [CI95%: -2.90, -0.52], p = .01; ROM = 4.61 [CI95%: 0.93, 8.30], p = .04). Additionally, VAS measures were influenced by follow-up times (VAS rest = -0.73 cm [CI95%: -1.30, -0.17], p = 0.03; VAS open = -0.97 cm [CI95%: -1.57, -0.37], p < .01; VAS chew = -1.15 cm [CI95%: -1.73, -0.58], p < .01). At T1, EG demonstrated higher number of responders compared to CG for VAS open (χ2(1) = 4.39, p = .04) and VAS chew (χ2(1) = 11.58, p < .01). CONCLUSION: Adding MPT to education and OS yields better outcomes in terms of pain reduction and ROM improvement, in chronic M-TMD. TRIAL REGISTRATION NUMBER: NCT03726060.

Shared epigenetic alterations between oral cancer and periodontitis: A preliminary study.

INTRODUCTION: We recently developed a non-invasive sampling procedure for oral squamous cell carcinoma (OSCC) detection based on DNA methylation analysis of a panel of 13 genes. Oral cancer, as well as acute and chronic inflammatory diseases, may influence the methylation level of several genes in the oral cavity. In the present study, we evaluated the presence of periodontal disease (PD) and the methylation status using our 13-gene panel. METHODS: Oral brushing specimens were collected from three different patient groups: 23 gingival OSCC patients, 15 patients affected by PD, and 15 healthy volunteers lacking evidence of PD. DNA methylation analysis was performed and each sample was determined to be positive or negative based on a predefined cut-off value. RESULTS: Positive results were found for 23/23 OSCC patients, 3/15 PD patients, and 0/15 samples from healthy volunteers. The GP1BB and MIR193 genes in the PD group exhibited mean methylation levels similar to OSCC patients. ZAP70 showed different methylation levels among three groups. CONCLUSION: Preliminary data identified shared epigenetic alterations between PD and OSCC patients in two inflammatory genes (GP1BB and MIR193). This study may help to identify potential links between the two diseases and serve as a starting point for the future research focused on pathogenesis.

Guided bone regeneration using titanium mesh to augment 3-dimensional alveolar defects prior to implant placement. A pilot study.

OBJECTIVES: To evaluate the outcomes of bone regeneration using a customized titanium mesh scaffold to cover a bone graft for reconstruction of complex defects of the jaws. MATERIALS AND METHODS: 19 large defects were digitally reconstructed using CT scans according to the prosthetic requirements. A titanium mesh scaffold was designed to cover the bone (autologous/bovine bone particulate) graft. At least 6 months after surgery, a new cone-beam CT was taken. The pre- and postoperative CT datasets were then converted into three-dimensional models and digitally aligned. The actual mesh position was compared to the virtual position to assess the reliability of the digital project. The reconstructed bone volumes (RBVs) were calculated according to the planned bone volumes (PBVs), outlining the areas under the mesh. These values were then correlated with the number of exposures, locations of atrophy, and virtually planned bone volume. RESULTS: The mean matching value between the planned position of the mesh and the actual one was 82 ± 13.4%. 52.3% (40% early and 60% late) exposures were observed, with 15.8% exhibiting infection. 26.3% resulted as failures. The amount of reconstructed bone volume (RBV) in respect to PBV was 65 ± 40.5%, including failures, and 88.2 ± 8.32% without considering the failures. The results of the exposure event were statistically significant (p = .006) in conditioning the bone volume regenerated. CONCLUSIONS: This study obtained up to 88% of bone regeneration in 74% of the cases. The failures encountered (26%) should underline the operator's expertise relevance in conditioning the final result.

A 3-Dimensional Evaluation of Bone Density in Alveolar Cleft Grafting Methods: Bone Substitutes Versus Autologous Bone.

INTRODUCTION: Secondary alveolar cleft repair using autologous bone graft is currently the gold standard in treating residual alveolar clefts. Despite its effectiveness, this technique is still burdened by several withdrawals, mostly related to donor site morbidity. To decrease disadvantages for patients, numerous attempts in the literature regarding bone substitutes have been described. The aim of this study is to compare the viability of bovine-based replacement bone material with respect of autologous bone graft in alveolar cleft reconstruction, through 3-dimensional alveolar cleft segmentation and bone density evaluation from preoperative and postoperative cone-beam computed tomography. PATIENTS AND METHODS: A retrospective cohort study of 10 patients who underwent surgical procedure for alveolar cleft grafting at Sant'Orsola Malpighi University Hospital of Bologna from December 2012 to December 2016 was undertaken. Five patients received autologous bone graft and 5 a bovine bone substitute graft. Preoperative and immediate postoperative orthopanoramic x-rays were recorded. Cone-beam computed tomography scans have recorded both pre and postoperatively. Volumetric evaluation on 3-dimensional cone-beam computed tomography images was performed. RESULTS: Alveolar clefts repaired using substitute bovine bone/biological membrane scaffold had a mean fill of 69.00% of total cleft volume, while this figure was of 67.07% with autologous bone grafting. The immediate postoperative course and subsequent discharge were uneventful for both groups, with a difference in timing. The cost of substitute bovine bone was offset by cost savings associated with a reduction in operative and postoperative and hospitalization time. CONCLUSIONS: Bone substitutes showed to be a promising solution in alveolar cleft grafting.

Validation of a Cleanroom Compliant Sonication-Based Decellularization Technique: A New Concept in Nerve Allograft Production.

Defects of the peripheral nervous system are extremely frequent in trauma and surgeries and have high socioeconomic costs. If the direct suture of a lesion is not possible, i.e., nerve gap > 2 cm, it is necessary to use grafts. While the gold standard is the autograft, it has disadvantages related to its harvesting, with an inevitable functional deficit and further morbidity. An alternative to autografting is represented by the acellular nerve allograft (ANA), which avoids disadvantages of autograft harvesting and fresh allograft rejection. In this research, the authors intend to transfer to human nerves a novel technique, previously implemented in animal models, to decellularize nerves. The new method is based on soaking the nerve tissues in decellularizing solutions while associating ultrasounds and freeze-thaw cycles. It is performed without interrupting the sterility chain, so that the new graft may not require post-production γ-ray irradiation, which is suspected to affect the structural and functional quality of tissues. The new method is rapid, safe, and inexpensive if compared with available commercial ANAs. Histology and immunohistochemistry have been adopted to evaluate the new decellularized nerves. The study shows that the new method can be applied to human nerve samples, obtaining similar, and, sometimes better, results compared with the chosen control method, the Hudson technique.

Microsurgical Reconstruction of the Nose: The Aesthetic Approach to Total Defects.

BACKGROUND: Reconstruction of complex defects involving nose and close facial units represents an aesthetic and functional challenge. Restoring satisfactory nasal shape, combining aesthetic, nasal function and patent airways is mandatory. In this paper, we describe our approach to total nose defects and we report our 20-year experience in microvascular nose reconstruction.Clinical cases are shown to illustrate different surgical techniques and the evolution of our approach. METHODS: Nasal reconstruction procedures were performed on 21 patients between 2000 and 2020 using the radial forearm flap (RFF) or anterolateral thigh (ALT) flap. Reported reconstructions included total/subtotal nasal defects, caused by cancer resections. The key point of our approach is the expanded forehead flap for skin coverage. Reconstruction is completed by cartilage grafts to restore nasal framework and to shape nasal tip. Ancillary procedures were needed in some cases to optimize aesthetic outcomes. RESULTS: Twenty-one patients completed the multistage nasal reconstruction. The RFF flap was used in 56% of the cases (n = 11), while the ALT flap was used in 44% (n = 10) of our case series. No difference has been detected in the number of reconstructive stages required to achieve the final result comparing RFF and ALT reconstruction (3.3 vs. 3.1 reconstructive steps). Ancillary procedures were performed in 7 patients. CONCLUSION: Microvascular tissue transfer plays a key role in full-thickness nasal defects restoration. Comparing the two groups, both the RFF and ALT are effective and reliable options in lining reconstruction, although with different indications. Expanded forehead flap, combined to free cartilage graft, is our gold standard to provide external skin coverage to rebuild the nasal framework. According to our current approach, accurate preoperative planning, supported by modern technologic tools, multistage reconstruction, and ancillary procedures are useful to accomplish satisfactory functional and aesthetic outcomes.

Flapless and bone-preserving extraction of partially impacted mandibular third molars with dynamic navigation technology. A report of three cases.

AIM: Most of the intra- and postoperative patient discomfort related to complex mandibular third molar (M3M) extraction is proportional to the invasiveness of the surgery. This can be minimized through the support of dynamic navigation (DN) technology, which can be successfully applied in dental implantology. Materials and methods: Three patients, one female (aged 25 years) and two males (aged 18 and 51 years, respectively) underwent the DN-supported extraction of partially impacted M3Ms with a flapless approach that required minimal bone removal. The patients' discomfort and the speed of recovery were considered to be proof of the quality of the adopted procedure. RESULTS: No postoperative discomfort such as pain or swelling was recorded in the immediate postoperative period, and no complications were reported within a month of the surgery. No medications were prescribed. The procedure lasted no longer than 20 min in all cases. CONCLUSION: Using DN technology, the real-time 3D monitoring of the clinical situation in each surgical phase enabled the surgeon to avoid soft tissue detachment as well as limit bone loss and intraoperative bleeding, thanks to a precise multi--section of the tooth and important nearby anatomical structures, respectively.

Surgical Management of Primary Chronic Osteomyelitis of the Jaws: The Use of Computer-Aided-Design/Computer-Aided Manufacturing Technology for Segmental Mandibular Resection.

The term osteomyelitis of the jaws identifies different pathological patterns characterized by the involvement of the cortical bone and bone marrow in osteoarticular infections.At the head and neck level, the segment most affected by osteomyelitis is the mandible and in most of the cases the cause of the infection is bacterial, as a result of pulp or periodontal infections, post-extraction alveolitis, foreign bodies and fractures. The mandibular PCO often presents with an insidious onset, without a striking acute phase, and it is characterized by recurrent episodes of pain, swelling, lockjaw, latero-cervical lymphadenopathy, without signs of suppuration.Three patients have been collected and recorded for the study.The authors believe that in the more advanced cases of PCO in adult patients, in which the mandibular bone appears almost entirely sclerotic and deformed, and that are not responsive to pharmacological therapy or to conservative surgical therapies such as decortication, it is necessary to perform a complete removal of the portion affected by osteomyelitis, with lower alveolar nerve preservation and contextual reconstruction with free microvascular bone flap.Our review aims to describe the clinico-pathological features of a rare pathological entity, propose a surgical treatment algorithm using computer-aided-design/computer-aided manufacturing technology and review the existing literature.

Use of Kinesiography to Assess Mandibular Function Following Segmental Resection and Microvascular Reconstruction.

Mandibular reconstruction has attained adequate morphological outcomes. However, some patients encounter difficulties in oral function and limited mandibular movements. An objective: evaluation has seldom featured actual kinetic measurements after mandibular reconstruction.Thirty patients who underwent mandibular reconstruction using bony free flap were enrolled in the study. Twenty-two patients were recruited after surgery and compared to a control group of 8 healthy subjects; 8 patients underwent both pre and postoperative evaluations. For each patient, a kinesiographic scan was obtained, recording maximum mouth opening, maximal laterality, and maximal protrusion.All postoperative kinesiographic evaluations were performed at least 6 months after surgery to ensure complete healing. In the first group of 22 patients, all measured movements were less than those of healthy controls, in particular maximum mouth opening. In the second study group (pre and postoperative evaluation), the postsurgical values did not achieve the control ones, but were no less than the preoperative values, granting adequate functional outcomes.The kinesiograph appears useful for objectively recording the functional outcomes in patients who have undergone mandibular reconstruction. The postoperative jaw movements were acceptable, ensuring a sufficient functional recovery.

Three-Dimensional Evaluation on Cortical Bone During Orthodontic Surgical Treatment.

Adult patients' severe malocclusions, especially the skeletal ones, cannot be exclusively solved by the orthodontic treatment and therefore a combined orthodontic-surgical treatment is necessary. Today, numerous software allows to plane and to visualize the final treatment results simulating the best therapeutic option. This is a retrospective experimental study that aims to analyze the changes in the buccal cortical bone in patients undergoing orthodontics surgeries and to evaluate the correlation between the dental movement and the changes in the relative bone cortex. The study sample consists of 32 subjects. By applying the CBCT radiographic examinations, the measurements were made in well-defined points of reference. The 3D study of the dental changes of position and the cortical buccal bone related variation, suggests how the determined orthodontic movement of the dental element does not achieve an easily predictable bone variation. Therefore, it also suggests that there is no direct proportionality relationship between the extent of bone apposition/reabsorption and dental movement.

Pre-Operative Evaluation of DNA Methylation Profile in Oral Squamous Cell Carcinoma Can Predict Tumor Aggressive Potential.

BACKGROUND: Prognosis of oral squamous cell carcinoma (OSCC) is difficult to exactly assess on pre-operative biopsies. Since OSCC DNA methylation profile has proved to be a useful pre-operative diagnostic tool, the aim of the present study was to evaluate the prognostic impact of DNA methylation profile to discriminate OSCC with high and low aggressive potential. METHODS: 36 OSCC cases underwent neoplastic cells collection by gentle brushing of the lesion, before performing a pre-operative biopsy. The CpG islands methylation status of 13 gene (ZAP70, ITGA4, KIF1A, PARP15, EPHX3, NTM, LRRTM1, FLI1, MiR193, LINC00599, MiR296, TERT, GP1BB) was studied by bisulfite Next Generation Sequencing (NGS). A Cox proportional hazards model via likelihood-based component-wise boosting was used to evaluate the prognostic power of the CpG sites. RESULTS: The boosting estimation identified five CpGs with prognostic significance: EPHX3-24, EPHX3-26, ITGA4-3, ITGA4-4, and MiR193-3. The combination of significant CpGs provided promising results for adverse events prediction (Brier score = 0.080, C-index = 0.802 and AUC = 0.850). ITGA4 had a strong prognostic power in patients with early OSCC. CONCLUSIONS: These data confirm that the study of methylation profile provides new insights into the molecular mechanisms of OSCC and can allow a better OSCC prognostic stratification even before surgery.

Stability of Periodontal Healing Distal to the Mandibular Second Molar After Third Molar Coronectomy: A 3-Year Follow-Up Study.

PURPOSE: The stability of the periodontal attachment distal to the mandibular second molar after coronectomy of the third molar is still unclear. This study addressed the question of whether periodontal measures are stable over time among patients undergoing coronectomy. MATERIALS AND METHODS: This prospective cohort study enrolled 30 patients treated at the Unit of Oral and Maxillofacial Surgery of the University of Bologna. The predictor variables were the probing pocket depth (PPD), distance between the marginal crest and the bottom of the osseous defect (BOD), and distance between the cementoenamel junction and the BOD. Three points on the distal surface of the second molar were recorded: distobuccal, distomedial, and distolingual sites. The distobuccal site was used as the statistical unit. The Wilcoxon test for paired data and Kendall τb were used to evaluate all variables. The significance level was set at P < .05. RESULTS: The 3-year follow-up was completed by 27 patients (7 male and 20 female patients; mean age, 28 ± 7 years) with 30 third molars. At 3 years, the PPD was 4 ± 1.25 mm; no significant changes in PPD were recorded for all sites from 9 months to 3 years. For the marginal crest-BOD distance and the cementoenamel junction-BOD distance, significant reductions were evident between preoperative values and those at 9 to 36 months (P = .001) and between values at 9 and 36 months (P = .02). CONCLUSIONS: A clinical healthy periodontium distal to the second molar was observed 36 months after coronectomy. However, further studies are necessary to confirm these preliminary clinical results.

Virtual Orthodontic Surgical Planning to Improve the Accuracy of the Surgery-First Approach: A Prospective Evaluation.

PURPOSE: We developed an innovative computer-assisted method to increase the accuracy of the surgery-first (SF) approach by linking the virtual orthodontic planning (VOP) with the virtual surgical planning (VSP). MATERIALS AND METHODS: Fifteen consecutive patients were enrolled from 2013 to 2015. All 15 patients had initially undergone cone-beam computed tomography (CBCT; 15 × 15 field-of-view) and intraoral digital scanning of the dental arches. The DICOM (Digital Imaging and Communications in Medicine) data set and STL files were processed using the SimPlant O&O platform (Dentsply-Sirona, York, PA), which facilitates skeletal, dental, and soft tissue modeling and subsequent realization of the VOP/VSP. The VSP was reproduced using computer-aided design and computer-aided manufacturing surgical splints, and the VOP was realized via postoperative orthodontic treatment. At the end of treatment, all the patients underwent repeat CBCT and digital scanning of the dental arches, and the new data sets were compared with the original data sets to determine the deviations. To evaluate skeletal accuracy, we assessed all points within an arbitrary range of -2 to +2 mm. To evaluate dental accuracy, the arbitrary range was -0.8 to +0.8 mm. RESULTS: The average duration of orthodontic treatment was 17.9 months. The accuracy of maxillary treatment averaged 0.0702 ± 2.0724 mm and that of mandibular treatment, 0.2811 ± 1.9993 mm. The average upper and lower dental arch accuracy was -0.0029 ± 1.125 and -0.0147 ± 1.263 mm, respectively. The maxillary surgery accuracy was 75.3% and that of mandibular surgery 74.0%, both within the -2 to +2-mm range. The upper and lower arch accuracy was 58.86 and 51.53%, respectively, both within the -0.8 to +0.8-mm range. CONCLUSIONS: The use of the VOP/VSP improved the diagnostic and therapeutic SF preoperative planning. VOP contributed significantly in this context. The accuracy of skeletal repositioning was acceptable; however, the VSP should be rendered more reproducibly in the future to minimize the need for orthodontic compensation and to maximize the advantages of SF.

Intratumoral Heterogeneity in Recurrent Metastatic Squamous Cell Carcinoma of the Oral Cavity: New Perspectives Afforded by Multiregion DNA Sequencing and mtDNA Analysis.

PURPOSE: Improvements in sequencing technologies have shown that genetic differences among neoplastic cells can reflect clonal expansion. Intratumor heterogeneity (ITH) has been suggested to explain differences in prognosis and treatment response, indicating that personalized medicine is the goal of the future. This study evaluated ITH in 5 patients with recurrent metastatic oral squamous cell carcinoma (OSCC) and tracked the evolution from non-neoplastic tissue to neoplastic events developing after primary tumor formation. PATIENTS AND METHODS: Representative regions were macrodissected from specimens obtained from patients with OSCC of the tongue (n = 4) and floor of the mouth (n = 1). ITH and tumor evolution were explored by analyzing DNA mutations disclosed by next-generation sequencing of specific driver genes combined with changes in the mtDNA D-loop hypervariable region. Phylogenetic trees were generated employing MAFFT tool with UPGMA/Jukes-Cantor serving as the substitute model. RESULTS: High levels of heterogeneity were observed within and among tumors. ITH emerged as metastatic and recurrent events progressed, but the evolutionary patterns differed. In some patients, specific subclones persisted during tumor relapse. Neighboring tissue also was heterogeneous at the premalignant level. CONCLUSIONS: A multiregion approach yielded more representative data than did single samples when tumors were subjected to molecular investigation. Persistent mutations that might be targeted by individualized medicine were thus exposed. Mitochondrial DNA is a useful adjunct tool when studying the phylogenetic evolution of subclones. The clinical implications of "field" heterogeneity should be studied in depth.

Auto-Allo Graft Parallel Juxtaposition for Improved Neuroregeneration in Peripheral Nerve Reconstruction Based on Acellular Nerve Allografts.

INTRODUCTION: Nerve repair poses a significant surgical challenge, and much research on this topic for improvement in reconstruction of segmental defects is ongoing. The aims of the study were to reconfirm the accuracy and safety of a previously described nerve decellularization method on a larger experimental population of rabbits, as well as on human nerves, and to establish in vivo the efficacy of a new-concept mixed graft, comprising autologous and acellular nerve allograft components within the same graft. METHODS: Acellular nerve allografts were implanted into tibial nerve defects of 5 rabbits (group A), autografts were implanted, representing the criterion standard, in other 5 animals (group B), and the innovative technique was used in the remaining 5 (group C). Twelve weeks postoperatively, nerve conduction evaluations were performed; animals were euthanatized, and grafts were harvested and morphologically, histomorphometrically, and immunohistochemically analyzed. Eventually, a preliminary in vitro validation of the decellularization method was performed on human nerves from a cadaver. RESULTS: No clinical adverse effect was revealed during all the experimental times. No tissue reaction was observed, and in all groups, regenerated fascicles and bundles were shown by histology. However, both histology and histomorphometry demonstrated a better regenerative efficiency in group C. The morphological evaluation of the human nerve treated with the novel method showed complete decellularization. CONCLUSION: The microsurgical combined model demonstrated a better neuroregeneration than did pure autografts and acellular nerve allografts. The decellularization method seemed effective also on human nerves. Deeper investigations are necessary to further validate and transfer this new encouraging protocol to the clinical arena.

Comprehensive Treatment of Facial Deformity Due to Radiotherapy in Rhabdomyosarcoma Patients: Distraction Osteogenesis and Free Flaps Surgical Technique.

Radiotherapy is essential for achieving and maintaining local control in head and neck rhabdomyosarcoma patients. However, radiotherapy may cause outgrowth disturbances of facial bone and soft tissue, resulting in facial asymmetry.Several studies have shown that the management of irradiated bones still remains challenging. The possibility of obtaining functional and aesthetic results when managing facial deformities due to radiation therapy with distraction osteogenesis combined with free flaps reconstruction is not common and not well documented in recent literature.In this report, we present the long-term results of distraction osteogenesis and soft tissue reconstruction via microvascular free flap to correct the facial hypoplasia of a young patient who underwent radiation therapy for rhabdomyosarcoma.This is the first presentation of 26 years long-term results in a patient who also underwent free flaps reconstruction as ancillary surgery for esthetic good results.

Augmented reality for dental implantology: a pilot clinical report of two cases.

BACKGROUND: Despite the limited number of articles dedicated to its use, augmented reality (AR) is an emerging technology that has shown to have increasing applications in multiple different medical sectors. These include, but are not limited to, the Maxillo-facial and Dentistry disciplines of medicine. In these medical specialties, the focus of AR technology is to achieve a more visible surgical field during an operation. Currently, this goal is brought about by an accurate display of either static or dynamic diagnostic images via the use of a visor or specific glasses. The objective of this study is to evaluate the feasibility of using a virtual display for dynamic navigation via AR. The secondary outcome is to evaluate if the use of this technology could affect the accuracy of dynamic navigation. CASE PRESENTATION: Two patients, both needing implant rehabilitation in the upper premolar area, were treated with flapless surgery. Prior to the procedure itself, the position of the implant was virtually planned and placed for each of the patients using their previous scans. This placement preparation contributed to a dynamic navigation system that was displayed on AR glasses. This, in turn, allowed for the use of a computer-aided/image-guided procedure to occur. Dedicated software for surface superimposition was then used to match the planned position of the implant and the real one obtained from the postoperative scan. Accuracies, using this procedure were evaluated by way of measuring the deviation between real and planned positions of the implants. For both surgeries it was possible to proceed using the AR technology as planned. The deviations for the first implant were 0.53 mm at the entry point and 0.50 mm at the apical point and for the second implant were 0.46 mm at the entry point and 0.48 mm at the apical point. The angular deviations were respectively 3.05° and 2.19°. CONCLUSIONS: From the results of this pilot study, it seems that AR can be useful in dental implantology for displaying dynamic navigation systems. While this technology did not seem to noticeably affect the accuracy of the procedure, specific software applications should further optimize the results.

Dynamic navigation: a prospective clinical trial to evaluate the accuracy of implant placement.

AIM: The objective of this prospective pilot clinical study was to evaluate the accuracy of a new dynamic navigation system and postoperative clinical outcomes. MATERIALS AND METHODS: Ten patients were recruited and 18 implants were placed. The surgery was performed with the navigation system and according to the virtual planning. Ten implants were placed using a flapless technique and eight implant sites were prepared with a combined piezo-drill method. The deviation between the real implant position obtained from the postoperative cone beam computed tomography (CBCT) scan and the planned implant position was measured. RESULT: The average deviation was 1.19 ± 0.54 mm. The mean deviation measured at the insertion point was 1.04 ± 0.47 mm and at the apical point it was 1.35 ± 0.56 mm. The depth error was 0.43 ± 0.34 mm. The axis deviation was 6.46 ± 3.95 degrees. No significant differences were found between the flapless and the open-flap approaches and between the conventional and piezoelectric techniques. No complications occurred. CONCLUSION: The accuracy values reported in this study are comparable, although not superior, to the literature data regarding dynamic and static computer-guided surgery. Dynamic navigation could increase the quality and safety of interventions and may reduce morbidity when compared with freehand insertion techniques. Deviation at the entry point (mm) Deviation at the apex (mm) Depth deviation (mm) Angular deviation (degrees) Mean 1.04 1.35 0.43 6.46 SD 0.47 0.56 0.34 3.95 Maximum 2.21 2.28 1.41 6.46 Minimum 0.45 0.59 0.03 3.95 Deviation at the entry point (mm)Deviation at the apex (mm)Depth deviation (mm)Angular deviation (degrees)OF0.96 ± 0.331.45 ± 0.600.35 ± 0.227.93 ± 5.15FL1.10 ± 0.581.27 ± 0.570.49 ± 0.425.28 ± 2.60Data are shown as mean ± SDOF = open-flap surgery; FL = flapless surgery Deviation at the entry point (mm)Deviation at the apex (mm)Depth deviation (mm)Angular deviation (degrees)P1.01 ± 0.251.37 ± 0.480.44 ± 0.267.63 ± 4.30C1.06 ± 0.621.34 ± 0.660.42 ± 0.415.52 ± 3.81Data are shown as mean ± SDP = piezoelectric tips; C = conventional burs.

A Noninvasive Test for MicroRNA Expression in Oral Squamous Cell Carcinoma.

MicroRNAs have recently been proposed as non-invasive biomarkers in Oral Squamous Cell Carcinoma (OSCC). The aim of this study was to analyze the expression of a panel of miRNAs in epithelial cells collected by oral brushing from OSCCs from regenerative areas after OSCC surgical resection and from their respective normal distant mucosa. Oral brushing specimens were collected from 24 healthy donors, 14 OSCC patients with specimens from tumour and normal distant mucosa, and from 13 patients who had OSCC resection, with samples from regenerative areas after OSCC resection and normal distant mucosa. Expression levels of eight targets (miR-21, miR-375, miR-345, miR-181b, miR-146a, miR-649, miR-518b, and miR-191) were evaluated by real-time Polymerase Chain Reaction (PCR). A highly significant between-group difference was found for miR-21 (F = 6.58, p < 0.001), miR-146a (F = 6.974, p < 0.001), and miR-191 (F = 17.07, p < 0.001). The major difference was observed between samples from healthy donors and from OSCC brushing, whereas no significant differences were observed between areas infiltrated by OSCC and their respective normal distant mucosa. Furthermore, altered expression of miR-146a and miR-191 was also observed in regenerative areas after OSCC resection. CONCLUSIONS: Oral brushing could be proposed as a noninvasive method to study microRNA expression in oral mucosa in OSCC patients.