Accuracy of ChatGPT-Generated Information on Head and Neck and Oromaxillofacial Surgery: A Multicenter Collaborative Analysis.

OBJECTIVE: To investigate the accuracy of Chat-Based Generative Pre-trained Transformer (ChatGPT) in answering questions and solving clinical scenarios of head and neck surgery. STUDY DESIGN: Observational and valuative study. SETTING: Eighteen surgeons from 14 Italian head and neck surgery units. METHODS: A total of 144 clinical questions encompassing different subspecialities of head and neck surgery and 15 comprehensive clinical scenarios were developed. Questions and scenarios were inputted into ChatGPT4, and the resulting answers were evaluated by the researchers using accuracy (range 1-6), completeness (range 1-3), and references' quality Likert scales. RESULTS: The overall median score of open-ended questions was 6 (interquartile range[IQR]: 5-6) for accuracy and 3 (IQR: 2-3) for completeness. Overall, the reviewers rated the answer as entirely or nearly entirely correct in 87.2% of cases and as comprehensive and covering all aspects of the question in 73% of cases. The artificial intelligence (AI) model achieved a correct response in 84.7% of the closed-ended questions (11 wrong answers). As for the clinical scenarios, ChatGPT provided a fully or nearly fully correct diagnosis in 81.7% of cases. The proposed diagnostic or therapeutic procedure was judged to be complete in 56.7% of cases. The overall quality of the bibliographic references was poor, and sources were nonexistent in 46.4% of the cases. CONCLUSION: The results generally demonstrate a good level of accuracy in the AI's answers. The AI's ability to resolve complex clinical scenarios is promising, but it still falls short of being considered a reliable support for the decision-making process of specialists in head-neck surgery.

The Use of Zirconia for Implant-Supported Fixed Complete Dental Prostheses: A Narrative Review.

The success of implant-supported fixed complete dental prostheses (ISFCDPs) depends on multiple factors: some are related to the fixtures, such as fixture material, surface characteristics, positioning, and type of connection to prosthetic components; others are related to the prostheses, such as design and materials used. Zirconia is a material widely used in fixed prosthodontics, whether on natural teeth or on implants, with excellent results over time. Regarding the use of zirconia for ISFCDPs, the 2018 ITI Consensus Report stated that "implant-supported monolithic zirconia prostheses may be a future option with more supporting evidence". Since CAD/CAM technology and zirconia are being continuously innovated to achieve better results and performances over time, a narrative review of the literature seems necessary to focus research efforts towards effective and durable solutions for implant-supported, full-arch rehabilitations. The objective of the present narrative review was to search the literature for studies regarding the clinical performance of zirconia-based ISFCDPs. According to the results of this review, the use of zirconia for ISFCDPs showed good clinical outcomes, with high survival rates ranging from 88% to 100% and prosthetic complications that were restorable by the clinicians in most cases.

Accuracy of Zygomatic Implant Placement Using a Full Digital Planning and Custom-Made Bone-Supported Guide: A Retrospective Observational Cohort Study.

The aim of the study was to evaluate the accuracy of zygomatic implant placement using customized bone-supported laser-sintered titanium templates. Pre-surgical computed tomography (CT) scans allowed to develop the ideal virtual planning for each patient. Direct metal laser-sintering was used to create the surgical guides for the implant placement. Post-operative CT scans were taken 6 months after surgery to assess any differences between the planned and placed zygomatic implants. Qualitative and quantitative three-dimensional analyses were performed with the software Slicer3D, recording linear and angular displacements after the surface registration of the planned and placed models of each implant. A total of 59 zygomatic implants were analyzed. Apical displacement showed a mean movement of 0.57 ± 0.49 mm on the X-axis, 1.1 ± 0.6 mm on the Y-axis, and 1.15 ± 0.69 mm on the Z-axis for the anterior implant, with a linear displacement of 0.51 ± 0.51 mm on the X-axis, 1.48 ± 0.9 mm on the Y-axis, and 1.34 ± 0.9 mm on the Z-axis for the posterior implant. The basal displacement showed a mean movement of 0.33 ± 0.25 mm on the X-axis, 0.66 ± 0.47 mm on the Y-axis, and 0.58 ± 0.4 mm on the Z-axis for the anterior implant, with a linear displacement of 0.39 ± 0.43 mm on the X-axis, 0.42 ± 0.35 mm on the Y-axis, and 0.66 ± 0.4 mm on the Z-axis for the posterior implant. The angular displacements recorded significative differences between the anterior implants (yaw: 0.56 ± 0.46°; pitch: 0.52 ± 0.45°; roll: 0.57 ± 0.44°) and posterior implants (yaw: 1.3 ± 0.8°; pitch: 1.3 ± 0.78°; roll: 1.28 ± 1.1°) (p < 0.05). Fully guided surgery showed good accuracy for zygomatic implant placement and it should be considered in the decision-making process.

Comparing prognostic utility between the 8th edition of TNM staging system and the lymph node ratio for oral squamous cell carcinoma.

BACKGROUND: Lymph node metastasis in oral squamous cell carcinoma (OSCC) is associated with poor prognosis. The 8th edition of TNM has implemented new nodal staging criteria. We assess the prognostic utility of the lymph node ratio (LNR) and compare it to that of pN in the TNM 8th edition. METHODS: One hundred and forty-two patients with OSCC were retrospectively studied. Nodal staging was performed using the TMN 8th edition and the prognostic value of the LNR in terms of overall survival (OS) and disease-free survival (DFS) was evaluated. RESULTS: Fifty-seven patients were eligible for inclusion. The LNR was independently prognostic of OS (p = 0.02). Instead N classification was not significantly predictive of OS (p = 0.10). High LNRs resulted in decreases in OS of approximately 40% within 6 months after surgery. CONCLUSIONS: The LNR identifies patients with poor outcomes better than N classification. The lack of reliable LNR cutoffs compromises its utility in clinical practice.

Accuracy of Fibula Reconstruction Using Patient-Specific Cad/Cam Plates: A Multicenter Study on 47 Patients.

OBJECTIVES: This prospective study evaluated the accuracy of mandibular reconstruction using free fibular flaps (by comparing virtual plans to the three-dimensional postoperative results), and the extent of bone-to-bone contact after computer-assisted surgery. METHODS: We included 65 patients who underwent partial-continuity mandibular resections from February 2013 to January 2017, and evaluated virtual planning, surgical techniques, and accuracy. RESULTS: Forty-seven patients were analysed. A total of 112 fibular segments received 54 implants. We measured 227 distances between landmarks to assess the accuracy of reconstruction. Postoperative reconstruction accuracy ranged from 0.5 to 3 mm. CONCLUSION: Virtual surgical planning very accurately translated simulation into reality, particularly in patients requiring large, complex mandibular reconstructions using multiple fibular segments. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E2169-E2175, 2021.

Insertion of Zygomatic Implants with a Technical Modification of the Extrasinus Protocol: A Retrospective Case Series.

PURPOSE: The aim of this retrospective clinical case series report was to evaluate the outcomes of patients who underwent zygomatic implant surgery with a recent technical modification of the extrasinus surgical protocol. MATERIALS AND METHODS: The implant system presented in this study had a novel designed unthreaded body with a 12.5-mm sharp threaded apical end for obtaining maximum retention to the zygomatic bone. A total of 92 patients with severely atrophic maxillae were included in this study. All the patients were treated with a modification of the extrasinus protocol for insertion of 261 zygomatic implants. The mean follow-up of the patients was 34.5 ± 17.1 (SD) months (range: 6 to 72 months). The implant survival rate was the primary outcome. The intraoperative and postoperative complications were evaluated as additional criteria for success. RESULTS: The cumulative implant survival rate was 97.99%. Definitive or provisional prostheses were delivered on the same day of surgery, which resulted in an improvement in the quality of life of the patients. Five implants failed in four patients. No sinusitis or mucositis was seen in any of the patients. Eleven postoperative complications occurred in seven patients. CONCLUSION: The novel zygomatic surgery protocol introduced in this study can be an effective alternative to augmentation procedures and conventional implants, especially in cases of extremely atrophic posterior maxillae.

Dental implant-based oral rehabilitation in patients reconstructed with free fibula flaps: Clinical study with a follow-up 3 to 6 years.

BACKGROUND: Oral rehabilitation of patients after maxillofacial reconstructive surgery represents a challenge and stable prosthetic retention can be achieved with the use of dental implants. PURPOSE: This retrospective report aimed to evaluate implant-based oral rehabilitation following maxillofacial reconstruction with free fibula flaps. MATERIALS AND METHODS: A total of 14 patients who had reconstruction with fibula flaps either by CAD/CAM or conventional surgery were included in this study. A total of 56 implants (40 in flaps, 16 in native bone) were evaluated. Follow-up after reconstructive surgery ranged between 3.25 and 6.3 years. Follow-up after implant surgery ranged between 1.5 and 3.8 years. RESULTS: Overall survival rate was 85.7% in free fibula flaps and 85.6% in dental implants. Eight implants were lost in three patients and all of these failures were in dental implants inserted in free flaps. According to the results on patient basis, the implant survival was not influenced by any variable. CONCLUSIONS: The maxillofacial reconstruction with free fibula flap and oral rehabilitation with implant-supported prostheses after ablative surgery can be considered as an effective and safe procedure with successful aesthetic and functional outcomes.

Role of Axial Split Osteotomy of Free Fibula Flap in Mandibular Reconstruction and Dental Rehabilitation.

The fibula free flap (FFF) is regarded as the gold standard in mandibular reconstruction. Dental rehabilitation is important to improve the health-related quality of life of patients undergoing mandibular reconstruction. FFF provides adequate cortical bone osseous tissue for use in dental implantation. The application of "axial split osteotomy" via a double-barrel fibula graft may enable discrepancies between the native mandible and FFF to be avoided, thereby improving the likelihood of early and successful dental rehabilitation.

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.

Gabapentin affects the expression of inflammatory mediators on healthy gingival cells.

Gabapentin is one of the most used drugs to treat postoperative pain with antihyperalgesic properties and has a unique mechanism of action, which differentiates it from other commonly used drugs. Various studies have shown that the perioperative use of gabapentin reduces postoperative pain. In our study, fragments of gingival tissue of healthy volunteers were collected during operation. Gene expression of 29 genes was investigated in gingival fibroblasts cell culture treated with gabapentin, compared with untreated cells. Of the different chemokines and interleukins studied, only 10 were statistically significant (CCL1, CCR1, CCR4, CCR5, CCR6, ILI1A, ILI1B, IL5, IL6R, TNFSF10). The overexpression of these cytokines, obtained in many studies, leads us to think that gabapentin can interact and cause post-inflammatory gingival hyperplasia, but, probably, in our study the gabapentin has not the same effect, because we used gingival fibroblasts of healthy people.

A novel integrated platform for the identification of surgical margins in oral squamous cell carcinoma: results from a prospective single-institution series.

BACKGROUND: The optimal surgical margins assessment is capital in oral squamous cell carcinoma (OSCC) management. We evaluated the clinical benefits of integrating intraoperative macroscopic margin (MM) assessment and narrow band imaging (NBI). METHODS: Sixteen OSCC patients eligible for surgery were prospectively enrolled. For each patient, 2 to 6 bioptic samples of MM and NBI margins were obtained and histologically analyzed for the presence of dysplasia and lymphocytes. Microvessel density was investigated by CD34 immunohistochemistry. RESULTS: Taken together, 104 specimens were analyzed, including 15% tumors, 33% MM, 33% NBI margins, and 19% MM-NBI overlapping margins. The NBI margins were closer to the lesion in 50% cases, while the same number of MM were more conservative than NBI, irrespective of the tumor site. The rate of histologically positive margins was similar among the two methods, akin to the microvessel density. CONCLUSIONS: MM assessment should be integrated but not replaced with the NBI technology to allow for more conservative surgery.

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.

Fibula free flap pedicle ossification: Experience of two centres and a review of the literature.

PURPOSE: The osteogenic potential of vascularized periosteum has been described in a few cases in the literature, and many different factors have been pointed out as plausible. Our aim was to review the literature in order to give a complete overview of this topic and to report on our clinical experience. PATIENTS & METHODS: Our experience includes three patients who underwent maxillectomy and FFF reconstruction. A progressive reduction in mouth opening was noticed in the months after surgery, and CT scans showed calcified tissue around the pedicle. Surgical revisions were performed. No recurrences were noticed. A full systematic literature review was conducted, including studies published on or before September 2016. RESULTS: Clinically, free flap pedicle ossification is presented as trismus, hard swelling, and severe pain during movements, although the diagnosis is scarce and often fortuitous. From January 2010 to January 2016 we performed 68 FFF reconstructions, and the incidence of FFF pedicle ossification in our experience was 4.4%. CONCLUSION: Ossification of FFF pedicle is uncommon, but when it occurs, it has dramatic clinical consequences. Follow-up CT scan can be useful in diagnosis. In our experience, surgery should be performed only when the patient is symptomatic.

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.