[A Case of Severe Skin Disorder during Pembrolizumab Treatment for Recurrent Maxillary Gingival Carcinoma].

Immune checkpoint inhibitors are known to produce immune-related adverse events(irAE)that require medical management. Herein, we report a case of a patient treated with pembrolizumab who experienced a Grade 3 interrupted skin disorder. The patient is a 67-year-old female diagnosed with right maxillary gingival squamous cell carcinoma(cT4aN0M0, Stage ⅣA)and underwent partial right maxillectomy, right extended supra-omohyoid neck dissection, and maxillary reconstruction using a forearm flap. Six months postoperatively, late lymph node metastases with extracapsular spread was found in the right buccal lymph node and the left neck, and the patient underwent right buccal lymphadenectomy and left modified radical neck dissection. After postoperative combined chemoradiotherapy(cisplatin plus IMRT)followed by 13 courses of cetuximab plus paclitaxel, a recurrent lesion was found in the right buccal region. After 8 courses of pembrolizumab, a skin rash appeared on the forearm, chest, and back, which was diagnosed as Grade 3 irAE, requiring hospitalization. The patient was re-instituted after waiting for improvement of the skin disorder. The pembrolizumab at 75% reduction dose was re-administrated, and the patient has been followed up so far.

Ensuring communication redundancy and establishing a telementoring system for robotic telesurgery using multiple communication lines.

Assuring communication redundancy during the interruption and establishing appropriate teaching environments for local surgeons are essential to making robotic telesurgery mainstream. This study analyzes robotic telesurgery with telementoring using standard domestic telecommunication carriers. Can multiple carriers guarantee redundancy with interruptions? Three commercial optical fiber lines connected Hirosaki University and Mutsu General Hospitals, 150 km apart. Using Riverfield, Inc. equipment, Hirosaki had a cockpit, while both Mutsu used both a cockpit and a surgeon's console. Experts provided telementoring evaluating 14 trainees, using objective indices for operation time and errors. Subjective questionnaires addressed image quality and surgical operability. Eighteen participants performed telesurgery using combined lines from two/three telecommunication carriers. Manipulation: over 30 min, lines were cut and restored every three minutes per task. Subjects were to press a switch when noticing image quality or operability changes. Mean time to task completion was 1510 (1186-1960) seconds: local surgeons alone and 1600 (1152-2296) seconds for those under remote instructor supervision, including expert intervention time. There was no significant difference (p = 0.86). The mean error count was 0.92 (0-3) for local surgeons and 0.42 (0-2) with remote instructors. Image quality and operability questionnaires found no significant differences. Results communication companies A, B, and C: the A/B combination incurred 0.17 (0-1) presses of the environment change switch, B/C had 0, and C/A received 0.67 (0-3), showing no significant difference among provider combinations. Combining multiple communication lines guarantees communication redundancy and enables robotic telementoring with enhanced communication security.

Evaluation of Hard and Soft Tissue Responses to Four Different Generation Bioresorbable Materials-Poly-l-Lactic Acid (PLLA), Poly-l-Lactic Acid/Polyglycolic Acid (PLLA/PGA), Uncalcined/Unsintered Hydroxyapatite/Poly-l-Lactic Acid (u-HA/PLLA) and Uncalcined/Unsintered Hydroxyapatite/Poly-l-Lactic Acid/Polyglycolic Acid (u-HA/PLLA/PGA) in Maxillofacial Surgery: An In-Vivo Animal Study.

Bone stabilization using osteosynthesis devices is essential in maxillofacial surgery. Owing to numerous disadvantages, bioresorbable materials are preferred over titanium for osteofixation in certain procedures. The biomaterials used for osteosynthesis in maxillofacial surgery have been subdivided into four generations. No study has compared the tissue responses generated by four generations of biomaterials and the feasibility of using these biomaterials in different maxillofacial surgeries. We conducted an in vivo animal study to evaluate host tissue response to four generations of implanted biomaterial sheets, namely, PLLA, PLLA/PGA, u-HA/PLLA, and u-HA/PLLA/PGA. New bone volume and pertinent biomarkers for bone regeneration, such as Runx2, osteocalcin (OCN), and the inflammatory marker CD68, were analyzed, and the expression of each biomarker was correlated with soft tissues outside the biomaterial and toward the host bone at the end of week 2 and week 10. The use of first-generation biomaterials for maxillofacial osteosynthesis is not advantageous over the use of other updated biomaterials. Second-generation biomaterials degrade faster and can be potentially used in non-stress regions, such as the midface. Third and fourth-generation biomaterials possess bioactive/osteoconductivity improved strength. Application of third-generation biomaterials can be considered panfacially. Fourth-generation biomaterials can be worth considering applying at midface due to the shorter degradation period.

Development and Validation of Oral Health-Related Quality of Life Scale for Patients Undergoing Endodontic Treatment (OHQE) for Irreversible Pulpitis.

An oral health-related quality of life measure specific to patients undergoing endodontic treatment has not been developed. This study aimed to validate the oral health-related quality of life scale for patients undergoing endodontic treatment (OHQE) for irreversible pulpitis, comprised of 42 questions. Sixty-two patients with irreversible pulpitis, comprising 23 (37.1%) males and 39 (62.9%) females, were enrolled between August 2022 and February 2023. Data were collected at three time points: pretreatment, post-treatment, and at the second week post-treatment. Factor analysis revealed physical, psychological, and expectations as subscales of OHQE. Cronbach's alpha coefficients ranged from 0.87 to 0.95 for each subscale. Each subscale of the General Oral Health Assessment Index (GOHAI) was moderately correlated with the OHQE subscales. Good-poor analysis revealed a significant difference between the high-scoring and low-scoring groups for each OHQE subscale. The intraclass correlation coefficients of the OHQE subscales ranged from 0.89 to 0.95. Multivariate linear regression analysis revealed a significant correlation between the pretreatment and post-treatment psychological factors (p < 0.05). Thus, OHQE will help researchers and policymakers understand the impact of oral health on the quality of life of patients with irreversible pulpitis undergoing endodontic treatment. OHQE could contribute to the appropriate planning, treatment decisions, and management of dental treatment.

Real-time telementoring with 3D drawing annotation in robotic surgery.

BACKGROUND: In telementoring, differences in teaching methods affect local surgeons' comprehension. Because the object to be operated on is a three-dimensional (3D) structure, voice or 2D annotation may not be sufficient to convey the instructor's intention. In this study, we examined the usefulness of telementoring using 3D drawing annotations in robotic surgery. METHODS: Kyushu University and Beppu Hospital are located 140 km apart, and the study was conducted using a Saroa™ surgical robot by RIVERFIELD Inc. using a commercial guarantee network on optical fiber. Twenty medical students performed vertical mattress suturing using a swine intestinal tract under surgical guidance at the Center for Advanced Medical Innovation Kyushu University. Surgical guidance was provided by Beppu Hospital using voice, 2D, and 3D drawing annotations. All robot operations were performed using 3D images, and only the annotations were independently switched between voice and 2D and 3D images. The operation time, needle movement, and performance were also evaluated. RESULTS: The 3D annotation group tended to have a shorter working time than the control group (25.6 ± 63.2 vs. - 36.7 ± 65.4 min, P = 0.06). The 3D annotation group had fewer retries than the control group (1.3 ± 1.7 vs. - 1.1 ± 0.7, P = 0.006), and there was a tendency for fewer needle drops (0.4 ± 0.7 vs. - 0.5 ± 0.9, P = 0.06). The 3D annotation group scored significantly higher than the control group on the Global Evaluate Assessment of Robot Skills (16.8 ± 2.0 vs. 22.8 ± 2.4, P = 0.04). The 3D annotation group also scored higher than the voice (13.4 ± 1.2) and 2D annotation (16.2 ± 1.8) groups (3D vs. voice: P = 0.03, 3D vs. 2D: P = 0.03). CONCLUSION: Telementoring using 3D drawing annotation was shown to provide good comprehension and a smooth operation for local surgeons.

Association of the number of remaining teeth with kidney function in community-dwelling healthy older adults: a cross-sectional study.

Objectives: Although a few studies have investigated the relationship between kidney and oral function (number of remaining teeth), their results remain inconclusive. Therefore, this study aimed to investigate the relationship between kidney function and oral health in community-dwelling healthy elderlies and examine the factors associated with kidney function. Materials and Methods: We used cross-sectional data from the Shimane prefecture cohort recruited by the Center for Community-Based Health Research and Education in 2019. We collected clinical data on dental status, background factors and kidney function (estimated glomerular filtration rate [eGFR], mL/min/1.73 m2 and creatinine levels, mg/dL). Results: The study enrolled 481 participants, whose mean age was 66.7±7.4 years, and 223 (46.4%) participants were men. Multivariate analysis revealed significant correlations between eGFR (B=0.17, P=0.04), creatinine (B=-0.54, P<0.01), and the number of remaining teeth. The number of remaining teeth was associated with creatinine and eGFR, which are indicators of kidney function. Conclusion: This study suggests that preserving the teeth may prevent decline in kidney function. Dental professionals should provide instructions and professional care to reduce the risk of systemic diseases such as kidney dysfunction.

Nurses' Awareness of and Current Approaches to Oral Care in a Community Hospital in Japan: A Longitudinal Study of Dental Specialists' Interventions.

Objective: This study aimed to increase nurses' interest and priority in oral care by implementing educational interventions, such as teaching oral care methods suitable for each patient in clinical settings, over a period of one year. Materials and Methods: This study included all 150 nurses working in Unnan City Hospital in Japan who answered a questionnaire comprising 19 questions regarding awareness, actual implementation status of oral care provided, burden, and involvement with oral and maxillofacial surgery department of the hospital, along with participants' characteristics. The rate of interest in learning, need for oral care, time spent in oral care, and oral health-related caregiver burden index (OHBI) score were compared between pre- and post-intervention groups. Results: The number and rate of valid questionnaires were 136 and 90.7%, respectively. The mean years of clinical experience were 19.3 ± 12.5 years; 93.4% of the nurses were women. After the interventions by dental specialists, the nurses' level of interest in and priority to oral care were significantly higher than those before the interventions (p < 0.001), regardless of nurses' background, such as age, gender, or years of experience. However, the "burden" did not statistically decrease. Conclusions: This study shows that dental specialists succeeded in significantly increasing nurses' interest in and priority to oral care by intervening in clinical practice but failed in decreasing nurses' burden of oral care. In the future, we would like to investigate the problems that hinder the reduction of the sense of burden, reduce the burden of nurses' oral care, and improve oral care.

Field experiment of a telesurgery system using a surgical robot with haptic feedback.

PURPOSE: To verify the usefulness of haptic feedback in telesurgery and improve the safety of telerobotic surgery. METHODS: The surgeon's console was installed at two sites (Fukuoka and Beppu; 140 km apart), and the patient cart was installed in Fukuoka. During the experiment, the surgeon was blinded to the haptic feedback levels and asked to grasp the intestinal tract in an animal model. The surgeon then performed the tasks at each location. RESULTS: No marked differences in task accuracy or average grasping force were observed between the surgeon locations. However, the average task completion time was significantly longer, and the system usability scale (SUS) was significantly lower rating for remote operations than for local ones. No marked differences in task accuracy or task completion time were observed between the haptic feedback levels. However, with haptic feedback, the organ was grasped with a significantly weaker force than that without it. Furthermore, with haptic feedback, experienced surgeons in robotic surgery tended to perform an equivalent task with weaker grasping forces than inexperienced surgeons. CONCLUSION: The haptic feedback function is a tool that allows the surgeon to perform surgery with an appropriate grasping force, both on site and remotely. Improved safety is necessary in telesurgery; haptic feedback will thus be an essential technology in robotic telesurgery going forward.

Mandibular midline osteotomy for correction of bimaxillary transverse discrepancy: a technical note.

Bimaxillary transverse width discrepancies are commonly encountered among patients with dentofacial deformities. Skeletal discrepancies should be diagnosed and managed appropriately with possible surgical corrections. Transverse width deficiencies can present in varieties of combinations involving the maxilla and mandible. We observed that in a significant proportion of cases, the maxilla is normal, and the mandible showed deficiency in the transverse dimension after pre-surgical orthodontics. We designed novel osteotomy techniques to enhance mandibular transverse width correction, as well as simultaneous genioplasty. Chin repositioning along any plane is applicable concomitant with mandibular midline arch widening. When there is a requirement for larger widening, gonial angle reduction may be necessary. This technical note focuses on key points in management of patients with transversely deficient mandible and the factors affecting the outcome and stability. Further research on the maximum amount of stable widening will be conducted. We believe that developing evidence-based additional modifications to existing conventional surgical procedures can aid precise correction of complex dentofacial deformities.

Construction of redundant communications to enhance safety against communication interruptions during robotic remote surgery.

It is important to ensure the redundancy of communication during remote surgery. The purpose of this study is to construct a communication system that does not affect the operation in the event of a communication failure during telesurgery. The hospitals were connected by two commercial lines, a main line and a backup line, with redundant encoder interfaces. The fiber optic network was constructed using both guaranteed and best-effort lines. The surgical robot used was from Riverfield Inc. During the observation, a random shutdown and restoration process of either line was conducted repeatedly. First, the effects of communication interruption were investigated. Next, we performed a surgical task using an artificial organ model. Finally, 12 experienced surgeons performed operations on actual pigs. Most of the surgeons did not feel the effects of the line interruption and restoration on still and moving images, in artificial organ tasks, and in pig surgery. During all 16 surgeries, a total of 175-line switches were performed, and 15 abnormalities were detected by the surgeons. However, there were no abnormalities that coincided with the line switching. It was possible to construct a system in which communication interruptions would not affect the surgery.

A rare case of dentinogenic ghost cell tumor with concomitant odontoma.

Key Clinical Message: A case of dentinogenic ghost cell tumor occurring simultaneously with a clinically diagnosed odontoma. The occurrence of epithelial and mesenchymal tumors at the same site is very rare, but should be kept in mind during pathological diagnosis. Abstract: Dentinogenic ghost cell tumor (DGCT) is a rare and benign odontogenic tumor composed of ghost cells, calcified tissue, and dentin. We present an extremely rare case of a 32-year-old female who was clinically diagnosed with an odontoma presenting with a painless swelling in her maxilla. Radiographic examination showed a well-defined radiolucent lesion with tooth-like calcified areas. The tumor was resected under general anesthesia. No recurrence was noted at the 12-month follow-up. Histopathological examination of the surgically resected tumor yielded a diagnosis of DGCT with odontoma.

Telesurgery and telesurgical support using a double-surgeon cockpit system allowing manipulation from two locations.

BACKGROUND: Although several studies on telesurgery have been reported globally, a clinically applicable technique has not yet been developed. As part of a telesurgical study series conducted by the Japan Surgical Society, this study describes the first application of a double-surgeon cockpit system to telesurgery. METHODS: Surgeon cockpits were installed at a local site and a remote site 140 km away. Three healthy pigs weighing between 26 and 29 kg were selected for surgery. Non-specialized surgeons performed emergency hemostasis, cholecystectomy, and renal vein ligation with remote assistance using the double-surgeon cockpits and specialized surgeons performed actual telesurgery. Additionally, the impact of adding internet protocol security (IPsec) encryption to the internet protocol-virtual private network (IP-VPN) line on communication was evaluated to address clinical security concerns. RESULTS: The average time required for remote emergency hemostasis with the double-surgeon cockpit system was 10.64 s. A non-specialized surgeon could safely perform cholecystectomy or renal vein ligation with remote assistance. Global Evaluative Assessment of Robotic Skills and System Usability Scale scores were higher for telesurgical support-assisted surgery by a non-specialized surgeon using the double-surgeon cockpits than for telesurgery performed by a specialized surgeon without the double-cockpit system. Adding IPsec encryption to the IP-VPN did not have a significant impact on communication. CONCLUSION: Telesurgical support through our double-surgeon cockpit system is feasible as first step toward clinical telesurgery.

Postoperative Complications following Open Reduction and Rigid Internal Fixation of Mandibular Condylar Fracture Using the High Perimandibular Approach.

The high perimandibular approach is a feasible surgical technique for treating mandibular condylar fractures with open reduction and internal fixation, followed by fewer complications. Temporary trismus is the only postoperative complication that may occur. This study evaluated postoperative complications following open reduction and rigid internal fixation (OR-IF) of mandibular condylar fractures using the high perimandibular approach. Twenty consecutive patients undergoing OR-IF were included in this study. They included 11 male and 9 female patients, of an average age of 58.5 years, all of whom responded to a follow-up call at least 12 months after the surgery. All patients were evaluated for range of mouth opening, postoperative complications, and radiological findings. A statistical analysis of the relationship between range of mouth opening and related clinical parameters at 6 months postoperative evaluation was conducted. The fracture of the condylar neck was associated with a limited range of mouth opening and longer operation time. However, longer operation time was not associated with a limited range of mouth opening. The high perimandibular approach with OR-IF in mandibular condylar fractures is a feasible and safe technique; however, prolonged surgery and mandibular condylar neck fractures could affect the postoperative range of mouth opening.

[A Case of Reconstruction of the Osteoradionecrosis of the Jaw Using the Patient-Specific Custom-Made Cutting Guide and Mandibular Reconstruction Plate].

Multidisciplinary treatment, combining ablative surgery and reconstruction, radiotherapy, and chemotherapy, is used to treat advanced oral cancers. In this study, we report a case of extensive osteoradionecrosis of the mandible following multidisciplinary treatment for tongue cancer, in which a computer-assisted, patient-specific custom-made cutting guide and reconstruction plate(TruMatch® )were used to improve the patient's facial morphology and oral-maxillofacial functioning. A 70-year-old man received multidisciplinary treatment for squamous cell carcinoma of the left side of the tongue (cT3N2bM0, cStage ⅣA)at a previous hospital. Seven years postoperatively, bilateral osteoradionecrosis of the mandible developed, and the patient was referred to our department for further treatment. Since the lesions were extensive, we planned reconstructive surgery using the TruMatch® system in collaboration with the plastic surgery department of our hospital. Surgery was performed precisely and accurately according to the preoperative simulation. Postoperatively, the patient's recovery was uneventful. The TruMatch® system enables us to achieve good morphological and comprehensive functional oral-maxillofacial reconstruction.

Fast Eating Speed Could Be Associated with HbA1c and Salt Intake Even after Adjusting for Oral Health Status: A Cross-Sectional Study.

This study aimed to examine the relationship between eating speed and hemoglobin A1c (HbA1c), considering the number of teeth, using cross-sectional health examination data from community-dwelling older individuals in Japan. We used data from the Center for Community-Based Healthcare Research and Education Study in 2019. We collected data on gender, age, body mass index, blood test results, Salt intake, bone mineral density, body fat percentage, muscle mass, basal metabolic rate, number of teeth, and lifestyle information. Eating speed was evaluated subjectively as fast, normal, or slow. Overall, 702 participants were enrolled in the study and 481 participants were analyzed. Multivariate logistic regression analysis revealed a significant association between fast eating speed and being a male (odds ratio [95% confidence interval]: 2.15 [1.02-4.53]), HbA1c (1.60 [1.17-2.19]), salt intake (1.11 [1.01-1.22]), muscle mass (1.05 [1.00-1.09]), and enough sleep (1.60 [1.03-2.50]). Fast eating may be associated with overall health and lifestyle. The characteristics of fast eaters, after taking oral information into consideration, tended to increase the risk of type 2 diabetes, renal dysfunction, and hypertension. Dental professionals should provide dietary and lifestyle guidance to fast eaters.

Lactate secreted via MCT4 from bone­colonizing breast cancer excites sensory neurons via GPR81.

Breast cancer (BC) bone metastasis causes bone pain (BP), which detrimentally damages the quality of life and outcome of patients with BC. However, the mechanism of BC­BP is poorly understood, and effective treatments are limited. The present study demonstrated a novel mechanism of BC­BP using a mouse model of bone pain, in which mouse (EO771) and human (MDA­MB­231) BC cells were injected in the bone marrow cavity of tibiae. Western blot analysis using sensory nerves, in vivo assessment of cancer pain and in vitro calcium flux analysis were performed. These mice developed progressive BC­BP in tibiae in conjunction with an upregulation of phosphorylated pERK1/2 and cAMP­response element­binding protein (pCREB), which are molecular indicators of neuron excitation, in the dorsal root ganglia (DRG) of sensory nerves. Importantly, mice injected with BC cells, in which the expression of the lactic acid transporter monocarboxylate transporter 4 (MCT4) was silenced, exhibited decreased BC­BP with downregulated expression of pERK1/2 and pCREB in the DRG and reduced circulating levels of lactate compared with mice injected with parental BC cells. Further, silencing of the cell­surface orphan receptor for lactate, G protein­coupled receptor 81 (GPR81), in the F11 sensory neuron cells decreased lactate­promoted upregulation of pERK1/2 and Ca2+ influx, suggesting that the sensory neuron excitation was inhibited. These results suggested that lactate released from BC cells via MCT4 induced BC­BP through the activation of GPR81 of sensory neurons. In conclusion, the activation of GPR81 of sensory neurons by lactate released via MCT4 from BC was demonstrated to contribute to the induction of BC­BP, and disruption of the interactions among lactate, MCT4 and GPR81 may be a novel approach to control BC­BP.

Technical evaluation of robotic tele-cholecystectomy: a randomized single-blind controlled pilot study.

Although robotic telesurgery is growing in popularity, the benefits of telesurgery compared to local surgery are unclear. This study aimed to evaluate the performance of robotic tele-cholecystectomy with a commercial line using the Saroa™ (Riverfield, Inc., Tokyo, Japan) system. The operation rooms of the Hokkaido University Hospital and Kushiro City General Hospital were connected using a best effort-type line (1 Gbps), with a distance of 250 km between the two hospitals. In this experimental single-blind randomized crossover trial, eight expert robotic surgeons performed robotic cholecystectomy in an artificial organ model using the Saroa™ system and were randomized to begin with either local surgery or telesurgery. All surgeons were assessed on task completion time, total path length of the right- and left- hand forceps and camera, Global Evaluative Assessment of Robotic Skills (GEARS), Global Operative Assessment of Laparoscopic Skills (GOALS), and System and Piper Fatigue Scale-12 (PFS-12). In all experiments, the communication environment was stable and the mean communication delay was 8 ms (3-31 ms). All tele-cholecystectomies were performed safely. There was no significant difference in completion time (P = 0.495), score of GEARS (P = 0.258), GOALS (P = 0.180), or PFS-12 (P = 0.528) between local surgery and telesurgery. The total path of the forceps tended to be longer in tele-cholecystectomy, particularly with significantly longer left-hand forceps total path length (P = 0.041). Robotic tele-cholecystectomy using a commercial line can be performed safely as same as local robotic surgery, but the total path of the left-hand forceps was prolonged in robotic tele-cholecystectomy due to overshoot. Therefore, a solution for overshooting will be required in the future.

Oral Dysfunction in Patients with Oral Cancer Could Occur Before Treatment and Require Early Nutritional Improvement: A Cross-Sectional Study.

Patients with oral cancer have poor nutritional status before treatment. However, there have been no reports of the detailed evaluation of preoperative oral function in patients with oral squamous cell carcinoma (OSCC). Therefore, this study aimed to evaluate the preoperative oral function of patients with OSCC and examine the relationship with nutritional status. Oral function measurements (microorganisms, oral dryness, occlusal force, tongue pressure, masticatory function, Eating Assessment Tool, and Postoperative Oral Dysfunction Scale) and Mini Nutritional Assessment-Short Form (MNA-SF) data were collected from 51 patients with OSCC (men: 37, women: 14, mean age: 72.1 years) who visited the Shimane University Hospital, Department of Oral and Maxillofacial Surgery, from September 2019 to September 2021. The tongue was the most prevalent primary gingiva site [22 patients (43.1%)], and 36 patients (70.6%) had advanced cancer. Comparisons between nutritional status and each related factor revealed significant differences in the number of individuals in the household, cancer stage, presence of pulmonary disease, number of teeth, microorganisms (grade), and masticatory function (mg/dL) (p < 0.05). Multiple regression analysis using the total MNA-SF score as the dependent variable with adjustment for confounding factors showed significant association between oral dryness and tongue pressure (p < 0.05). No significant association was found for the Eating Assessment Tool or Postoperative Oral Dysfunction scale. Patients with OSCC may have decreased oral function because of the tumor at the time of diagnosis, which causes a decline in nutritional status. Preoperative interventions are necessary to improve nutrition based on the state of oral function.

Genioplasty in Contemporary Orthognathic Surgery.

In contemporary orthognathic surgery planning, the genium/chin constitutes an important part that contributes to the maxillofacial profile. The aesthetics of the lower face is affected by the position of the genium which makes reestablishment of genial morphology an essential component. It is hence necessary to evaluate the genium objectively on its individual merit, and any discrepancy is addressed accordingly. This review presents an overview of contemporary genioplasty techniques, their applications, and considerations on stability, osteosynthesis, complications, and the future developments.

In Vivo Evaluation of Bone Regenerative Capacity of the Novel Nanobiomaterial: ß-Tricalcium Phosphate Polylactic Acid-co-Glycolide (ß-TCP/PLLA/PGA) for Use in Maxillofacial Bone Defects.

Maxillofacial bone defects are treated by autografting or filling with synthetic materials in various forms and shapes. Electrospun nanobiomaterials are becoming popular due to their easy placement and handling; combining ideal biomaterials extrapolates better outcomes. We used a novel electrospun cotton-like fiber made from two time-tested bioresorbable materials, ß-TCP and PLLA/PGA, to check the feasibility of its application to maxillofacial bone defects through an in vivo rat mandibular bone defect model. Novel ß-TCP/PLLA/PGA and pure ß-TCP blocks were evaluated for new bone regeneration through assessment of bone volume, inner defect diameter reduction, and bone mineral density. Bioactive/osteoconductivity was checked by scoring the levels of Runt-related transcription factor x, Leptin Receptor, Osteocalcin, and Periostin biomarkers. Bone regeneration in both ß-TCP/PLLA/PGA and ß-TCP was comparable at initial timepoints. Osteogenic cell accumulation was greater in ß-TCP/PLLA/PGA than in ß-TCP at initial as well as late phases. Periostin expression was more marked in ß-TCP/PLLA/PGA. This study demonstrated comparable results between ß-TCP/PLLA/PGA and ß-TCP in terms of bone regeneration and bioactivity, even with a small material volume of ß-TCP/PLLA/PGA and a decreased percentage of ß-TCP. Electrospun ß-TCP/PLLA/PGA is an ideal nanobiomaterial for inducing bone regeneration through osteoconductivity and bioresorbability in bony defects of the maxillofacial region.