Impact of COVID-19 pandemic on the dynamic of patients with oral and maxillofacial trauma: interrupted time-series analysis.

Oral and maxillofacial trauma is influenced by various factors, including regional characteristics and social background. Due to the coronavirus disease 2019 (COVID-19) pandemic, a state of emergency was declared in Japan in March 2020. In this study, we aimed to examine the dynamics of patients with oral and maxillofacial trauma over a 12-years period using interrupted time-series (ITS) analysis. Patients were examined at the Shimane University Hospital, Maxillofacial Trauma Center from April 2012 to April 2023. In addition to general patient characteristics, data regarding the type of trauma and its treatment were obtained from 1203 patients (770 men and 433 women). Group comparisons showed significant differences in age, trauma status, method of treatment, referral source, route, and injury occasion. ITS analysis indicated significant changes in combined nasal fractures, non-invasive reduction, and sports injuries (P < 0.05), suggesting COVID-19 significantly impacted oral and maxillofacial trauma dynamics. A pandemic of an infectious disease may decrease the number of minor trauma cases but increase the number of injuries from outdoor activities, resulting in no overall change in the dynamics of the number of trauma patients. Medical systems for oral and maxillofacial trauma should be in place at all times, independent of infectious disease pandemics.

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.

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.

[Two Cases of Advanced Lower Gingival Carcinoma Treated Surgically Using a Novel Patient-Specific Full Custom- Made Mandibular Reconstruction Plate System].

The treatment of advanced lower gingival carcinoma requires postoperative chemoradiotherapy; therefore, simultaneous hard-tissue reconstruction may not be indicated. In these cases, mandibular reconstruction is performed using a temporal reconstruction plate and various skin flaps. Herein, we reported 2 cases of advanced lower gingival carcinoma treated with a novel computer-assisted patient-specific, fully custom-made mandibular reconstruction plate system(Cosmofix®)in combination with a pedicle/free flap. In case 1, an 80-year-old female patient was diagnosed with right lower gingival carcinoma( cT4aN3bM0, Stage ⅣB). Under general anesthesia, she underwent tracheostomy, bilateral neck dissection, segmental mandibulectomy, and mandibular reconstruction using Cosmofix® in combination with an ulnar forearm free flap. In case 2, an 81-year-old male patient was diagnosed with right lower gingival carcinoma(cT4aN2bM0, Stage ⅣA). The patient underwent maintenance dialysis and required minimally invasive surgery using a pedicle flap. Under general anesthesia, the patient underwent tracheostomy, right modified radical neck dissection, segmental mandibulectomy, and mandibular reconstruction using Cosmofix® in combination with a pectoralis major myocutaneous flap. Postoperative facial morphology, occlusion, eating, swallowing, articulation, and other dysfunctions were minimal in both the cases. Adjuvant chemoradiotherapy was recommended. In conclusion, the utilization of the Cosmofix® system enabled both esthetic and functional reconstruction following segmental mandibulectomy for advanced lower gingival carcinoma.

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.