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.

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.

[A Case of Recurrent Tongue Cancer in a Patient of AYA Generation Who Underwent Salvage Surgery and Oral-Maxillofacial Reconstruction after Super-Selective Intra-Arterial Chemoradiotherapy].

Radical tumor resection for oral cancer can cause morphological and esthetic disorders and oral and maxillofacial dysfunction and maintaining a social life could become challenging, especially in the adolescents and young adults(AYA)generation. Conversely, chemoradiotherapy for young patients may cause adverse reactions such as impaired fertility and late side effects of radiation. Therefore, treatment should be performed cautiously. We report a case of AYA generation patient who underwent salvage surgery and maxillofacial reconstruction for recurrent tongue cancer after super-selective intra-arterial chemoradiotherapy. The patient was a 30-year-old woman who was 20 weeks pregnant. She was diagnosed with Stage Ⅲ squamous cell carcinoma of the right tongue, cT3N0M0. After abortion, the patient underwent super-selective intra-arterial chemoradiotherapy and achieved a complete response. However, 13 years later, a recurrence of Stage ⅣA tongue cancer, r- cT4aN2bM0, was reported. Additionally, the patient had osteoradionecrosis. We performed radical tumor resection(bilateral neck dissection plus subtotal glossectomy plus segmental mandibulectomy)and maxillofacial reconstruction with a fibula flap. Subsequently, we performed occlusal reconstruction treatment using dental implants. Three years postoperatively, no tumor recurrence was observed, and the patient was satisfied with the restored morpho-aesthetic and maxillo-oral functions.

[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.

[Effect of the Hyoid Bone Suspension Technique on the Preservation of Swallowing Function after Total Glossectomy and Pectoralis Major Musculocutaneous Flap Reconstruction for Locally Advanced Tongue Cancer].

Dysphagia is a major postoperative complication in patients with locally advanced oral cancer. In this case report, we describe the effect of the hyoid bone suspension technique on the preservation of swallowing function after total glossectomy and pectoralis major musculocutaneous flap reconstruction for locally advanced tongue cancer. Case: A 72-year-old Japanese male was diagnosed with advanced squamous cell carcinoma on the left side of his tongue(cT4aN2cM0, cStage ⅣA). Under general anesthesia, the patient underwent a tracheotomy, bilateral modified radical neck dissection type Ⅲ, total glossectomy, and reconstruction with a left pectoralis major musculocutaneous flap(PMMC flap). Intraoperatively, the PMMC flap was designed to have a heart shape of 11×6 cm and was elevated. Subsequently, holes were made at the lower edge of the mandible, and the hyoid bone was suspended and fixed to the mandibular border using 2-0 nylon sutures. The postoperative course was uneventful; the flap was completely engrafted and was in good condition. The hyoid bone suspension technique can reproduce the pharyngeal phase of swallowing, and the palatal augmentation prosthesis helps to improve food mass feeding and preserve the swallowing function.

[A Case of Lower Gingival Carcinoma Treated Surgically Using Computer-Assisted Patient-Specific Cutting Guide and Mandibular Reconstruction Plate].

We report a case of advanced lower gingival carcinoma treated with a computer-assisted custom-made surgical guide and reconstruction plate system(TruMatch®)in combination with a pectoralis major myocutaneous flap. In a 74-year-old male patient, a neoplastic lesion with a 30×30 mm periapical induration was observed around an extraction socket of left mandibular third molar. After various examinations, we diagnosed lower gingival carcinoma(cT4aN2bM0, Stage ⅣA). The patient was a paraplegic with a spinal cord injury, and reconstruction of mandible with free flap was not indicated, requiring minimally invasive surgery. Therefore, a surgical guide and reconstruction plate were prepared preoperatively using the Tru- Match® system. Under general anesthesia, the patient underwent tracheostomy, left modified radical neck dissection, segmental mandibulectomy, and reconstruction of the mandible using this system in combination with a pectoralis major myocutaneous flap. Postoperatively, the patient had minimal dysfunction. Currently, at 18 months follow up postoperatively, good prognosis was observed. In conclusion, this is a useful surgical system with accurate and less invasive surgery for segmental mandibulectomy of advanced lower gingival carcinoma.

[Oral Function Restoration via Two-Stage Reconstructive Treatment of an Extensive Maxillary Defect Following Maxillectomy].

Recently, the number of survivors that had oral cancer has increased, but deterioration in the quality of life of patients concerning oral function and cosmetic appearance has become problematic. Prosthodontic dentures usefully treat jaw defects after maxillary resection for cancer, but advances in microsurgery have rendered the possibility to reconstruct maxillary defect and oral cavity using a microvascular flap. Here, we describe 2-stage treatment after 35 years postoperatively. We restored the maxillofacial function using microvascular flaps and partial denture. The patient was a 59-year-old woman who underwent left lateral maxillectomy 35 years previously to treat an advanced left maxilla gingival carcinoma. A maxillary prosthesis was applied, requiring repeated adjustments and refabrications. The patient visited to obtain improvements for oral and maxillofacial functions and long-term quality of life. The left maxillary bone defect was 45×50 mm in area. Collaborating with the Department of Plastic and Reconstructive Surgery, the patient underwent reconstructive treatment using a microvascular forearm flap and partial denture. The patient's progress was excellent; eating, swallowing, and articulation improved. For 1 year postoperatively, the patient was satisfied with the results.

[A Case of Tongue Carcinoma with Malignant Transformation Caused by the Pandemic].

In April 2020, a state of emergency was declared because of the pandemic, and the public was instructed to refrain from leaving their homes. Consequently, this stirred up anxiety about visiting medical institutions. Here, we describe a case of tongue carcinoma that developed from an oral precancerous lesion into a malignant transformation owing to the effects of refraining from medical examinations caused by the pandemic. The patient was a 62-year-old woman. In March 2020, the patient became aware of a mass at the tongue's margin and was referred to our department. An excisional biopsy was performed, and a diagnosis of inflammatory change was made. The following month, a white ulcerative lesion was found, and another excisional biopsy was performed; therefore, a diagnosis of left tongue leukoplakia without epithelial dysplasia was made. The patient was scheduled for surgery; however, refused treatment and consultation because of the pandemic. In September 2021, the patient revisited our department on her own volition because an ulcerative lesion with indistinct borders and induration was found at the left lingual margin. Upon close examination, a diagnosis of left tongue squamous cell carcinoma(cT2N2bM0, Stage ⅣA)was made. In October 2021, radical tumor resection and reconstruction were performed. After 8 months postoperatively, the patient is currently well.

Bioactive Regeneration Potential of the Newly Developed Uncalcined/Unsintered Hydroxyapatite and Poly-l-Lactide-Co-Glycolide Biomaterial in Maxillofacial Reconstructive Surgery: An In Vivo Preliminary Study.

Uncalcined/unsintered hydroxyapatite (HA) and poly-l-lactide-co-glycolide (u-HA/PLLA/PGA) are novel bioresorbable bioactive materials with bone regeneration characteristics and have been used to treat mandibular defects in a rat model. However, the bone regenerative interaction with the periosteum, the inflammatory response, and the degradation of this material have not been examined. In this study, we used a rat mandible model to compare the above features in u-HA/PLLA/PGA and uncalcined/unsintered HA and poly-l-lactic acid (u-HA/PLLA). We divided 11 male Sprague-Dawley rats into 3- and 16-week groups. In each group, we assessed the characteristics of a u-HA/PLLA/PGA sheet covering the right mandibular angle and a u-HA/PLLA sheet covering the left mandibular angle in three rats each, and one rat was used as a sham control. The remaining three rats in the 16-week group were used for a degradation assessment and received both sheets of material as in the material assessment subgroup. At 3 and 16 weeks after surgery, the rats were sacrificed, and mandible specimens were subjected to micro-computed tomography, histological analysis, and immunohistochemical staining. The results indicated that the interaction between the periosteum and u-HA/PLLA/PGA material produced significantly more new bone regeneration with a lower inflammatory response and a faster resorption rate compared to u-HA/PLLA alone. These findings may indicate that this new biomaterial has ideal potential in treating maxillofacial defects of the midface and orbital regions.

[A Clinical Study of Orofacial Defect Reconstruction Using a Modified Submental Island Flap following Oral Cancer Resection].

INTRODUCTION: Pedicled flaps are used in orofacial defect reconstruction in older patients and patients with underlying diseases. The submental island flap(SIF)is one type of cervical pedicled flap; however, the modified submental island flap (MSIF), which includes mylohyoid muscle, is a simpler and safer type. Here, we report a clinical study of orofacial defect reconstruction using the MSIF following oral cancer resection. PATIENTS AND METHODS: From January 2019 to December 2020, we retrospectively examined 10 cases of reconstruction using the MSIF following oral squamous cell carcinoma resection. RESULTS: The study population consisted of 7 men and 3 women with a mean age of 76.0(66-88)years. The primary sites were lower gingiva(n=5), tongue(n=3), and buccal mucosa in(n=2). Surgical procedures included marginal mandibulectomy( n=3), segmental mandibulectomy(n=1), partial glossectomy(n=2), hemiglossectomy(n=1), buccal mucosa resection(n=2), and combined partial glossectomy and segmental mandibulectomy(n=1). The average flap size was 61.4×36.0 mm. The average time of flap elevation was 32.4(23-50)minutes. During orofacial surgery using the MSIF, organs adjacent to the primary site could also be reconstructed. There were no complications in any patients. CONCLUSION: The MSIF is useful for orofacial defect reconstruction in older patients and patients with underlying diseases.

A Narrative Review of u-HA/PLLA, a Bioactive Resorbable Reconstruction Material: Applications in Oral and Maxillofacial Surgery.

The advent of bioresorbable materials to overcome limitations and replace traditional bone-reconstruction titanium-plate systems for bone fixation, thus achieving greater efficiency and safety in medical and dental applications, has ushered in a new era in biomaterial development. Because of its bioactive osteoconductive ability and biocompatibility, the forged composite of uncalcined/unsintered hydroxyapatite and poly L-lactic acid (u-HA/PLLA) has attracted considerable interest from researchers in bone tissue engineering, as well as from clinicians, particularly for applications in maxillofacial reconstructive surgery. Thus, various in vitro studies, in vivo studies, and clinical trials have been conducted to investigate the feasibility and weaknesses of this biomaterial in oral and maxillofacial surgery. Various technical improvements have been proposed to optimize its advantages and limit its disadvantages. This narrative review presents an up-to-date, comprehensive review of u-HA/PLLA, a bioactive osteoconductive and bioresorbable bone-reconstruction and -fixation material, in the context of oral and maxillofacial surgery, notably maxillofacial trauma, orthognathic surgery, and maxillofacial reconstruction. It simultaneously introduces new trends in the development of bioresorbable materials that could used in this field. Various studies have shown the superiority of u-HA/PLLA, a third-generation bioresorbable biomaterial with high mechanical strength, biocompatibility, and bioactive osteoconductivity, compared to other bioresorbable materials. Future developments may focus on controlling its bioactivity and biodegradation rate and enhancing its mechanical strength.

[A Case of Recurrent Squamous Cell Carcinoma of the Mandibular Gingiva Around a Mandibular Dental Implant].

Extensive bimaxillary bone support devices(hereafter referred to as a dental implant)are useful for morphological and functional reconstruction after resection of oral cancer. However, tumor recurrence due to peri-implantitis may occur. In this report, we describe a case of squamous cell carcinoma(SqCC)recurrence around a mandibular dental implant. An 80-year- old female patient underwent tumor resection and stratification for SqCC extending from the left lingual margin to the gingiva of the left lower molar in 2013. In 2014, 2 dental implants were placed in the bilateral mandibular canine region and a prosthetic device of implant-overdenture was installed. Six years after the primary tumor resection, a mass lesion was found in the peri-implant area of the left mandibular canine. Upon examination, the patient was diagnosed with SqCC recurrence and underwent radical tumor resection and immediate reconstruction using a submental flap and a reconstruction plate. Additional dental implants were concurrently placed in the remaining mandible. There was no evidence of recurrence, and the patient remains under careful observation so far.

[A Case of Polymorphous Low-Grade Adenocarcinoma of the Palate].

Polymorphous low-grade adenocarcinoma(PLGA)is a relatively rare low-grade adenocarcinoma of the minor salivary glands. If radical resection is performed, the prognosis is favorable. We present the case of a 62-year-old woman who presented to our clinic in April 2019 after noticing a mass on her palate. The intraoral examination revealed a 10-mm-diameter, well-defined, tender mass extending from the right hard palate to the soft palate. We suspected a benign tumor originating from the area of transition between the hard and soft palates. An excisional biopsy of the mass was performed, and PLGA was diagnosed on the basis of histopathologic findings. In May 2019, the tumor was resected under general anesthesia and a soft palatal lift prosthesis was applied for functional recovery. In July 2020, the soft palate defect was repaired using an ulnar forearm free flap during a two-stage reconstruction procedure. The patient developed complete necrosis of the free flap, and the defect was re-reconstructed using a buccinator-based myomucosal flap. There was no evidence of disease recurrence or metastasis. Two years have passed since the initial surgery, and the patient's clinical course has been well so far.

Bone Regeneration Capacity of Newly Developed Uncalcined/Unsintered Hydroxyapatite and Poly-l-lactide-co-glycolide Sheet in Maxillofacial Surgery: An In Vivo Study.

Uncalcined/unsintered hydroxyapatite and poly-l-lactide-co-glycolide (u-HA/PLLA/PGA) is a new bioresorbable nanomaterial with superior characteristics compared with current bioresorbable materials, including appropriate mechanical properties, outstanding bioactive/osteoconductive features, and remarkably shorter resorption time. Nevertheless, the bone regeneration characteristics of this nanomaterial have not been evaluated in maxillofacial reconstructive surgery. In this study, we used a rat mandible model to assess the bone regeneration ability of u-HA/PLLA/PGA material, compared with uncalcined/unsintered hydroxyapatite and poly-l-lactide acid (u-HA/PLLA) material, which has demonstrated excellent bone regenerative ability. A 4-mm-diameter defect was created at the mandibular angle area in 28 Sprague Dawley male rats. The rats were divided into three groups: u-HA/PLLA/PGA (u-HA/PLLA/PGA graft + defect), u-HA/PLLA (u-HA/PLLA graft + defect), and sham control (defect alone). At 1, 3, 8, and 16 weeks after surgeries, the rats were sacrificed and assessed by micro-computed tomography, histological analysis with hematoxylin and eosin staining, and immunohistochemical analyses. The results confirmed that the accelerated bone bioactive/regenerative osteoconduction of u-HA/PLLA/PGA was comparable with that of u-HA/PLLA in the rat mandible model. Furthermore, this new regenerative nanomaterial was able to more rapidly induce bone formation in the early stage and had great potential for further clinical applications in maxillofacial reconstructive surgery.

[A Case of Early Detection and Treatment Applicable to Squamous Cell Carcinoma of the Palate Detected by Oral Cancer Mass Screening in Izumo 2019].

Treatment of oral cancer is based on radical resection and reconstructive surgery. Surgery causes impairment of maxillofacial morphology and function, including chewing and eating difficulties, and dysarthria. It is necessary to restore the maxillofacial morphology and function by reconstructive surgery and use of prostheses. Therefore, early detection and treatment are required to reduce these disabilities associated with oral cancers. Here, we report a case of oral cancer that was detected early by our oral cancer mass screening program in Izumo, Japan, in 2019. A 73-year-old woman presented with a reddish ulcerative region in the palate. Cytological screening indicated positive-suspected low squamous intraepithelial neoplasia (LSIL). The patient was diagnosed as squamous cell carcinoma of the palate(cT1N0M0, StageⅠ)in our hospital. We performed radical resection of the palate tumor and immediate reconstruction using a vascularized radial forearm flap. The clinical course was good and oral function was fully restored. It is important for oral surgeons to publicize and raise awareness of oral cancer, and to continue oral cancer mass screening programs.

[Secondary Maxillofacial Revision Reconstruction Using Custom-Made Artificial Bone Following Resection of Primary Intraosseous Mandibular Squamous Cell Carcinoma and Microvascularized Fibula Flap Reconstruction].

The basic treatment for oral cancer is radical tumor resection and reconstruction, which alters the maxillofacial morphology and causes dysfunction. Reconstructive surgery can be performed with bone and soft tissue transplantation, but it is invasive and good morphological repair is difficult. Custom-made artificial bone(CT-BoneTM)consisting of calcium-deficient hydroxyapatite was newly authorized for clinical use in April 2018. It enables precise, minimally invasive maxillofacial bone reconstruction. Here, we report favorable facial morphological improvement using CT-BoneTM in a patient with maxillofacial asymmetry following the resection of a primary intraosseous mandibular squamous cell carcinoma and microvascularized fibula flap reconstruction. The patient was a 52-year-old woman. In August 2010, she was diagnosed with primary intraosseous mandibular squamous cell carcinoma of the right mandible(T4aN0M0, Stage ⅣA)and underwent mandibular segmental resection, neck dissection, and free fibula flap reconstruction. Although her clinical course was uneventful, she wanted maxillofacial esthetic correction. Therefore, we performed maxillofacial revision reconstruction using computer-simulated custom-made CT-BoneTM in January 2020. It was stably fixed to the reconstructed mandible with bioactive/bioresorbable screws. The postoperative course was uneventful and maxillofacial symmetry was obtained to the patient's satisfaction at the 6 months follow-up.

[Surgical Procedure for Postoperative Reconstruction of Swallowing Function in a Very Elderly Patient with Advanced Tongue Cancer].

Surgical ablation and reconstruction are the first-line treatment strategies for squamous cell carcinoma of the tongue. However, locally advanced cases can be complicated by postoperative dysphagia. Here, we report a case of advanced tongue cancer in a very elderly patient who regained good swallowing function following a reconstructive surgery using a pectoralis major musculocutaneous flap with elevation of the hyoid bone. Case: An 89-year-old man diagnosed with advanced squamous cell carcinoma of the tongue(cT4aN2bM0, cStage ⅣA)underwent tracheostomy, right modified radical neck dissection type Ⅱ, left supraomohyoid neck dissection, subtotal glossectomy, and pectoralis major musculocutaneous flap reconstruction under general anesthesia. Intraoperatively, holes were created in the lower edge of the mandible, and the hyoid bone was suspended and fixed to the mandibular border using 2-0 nylon sutures. The postoperative course was uneventful. The flap had been completely engrafted and was in a good condition. The pharyngeal stage of swallowing function was reproduced through a reconstructive surgery with suspension and fixation of the hyoid bone toward the border of the mandible. Video fluorography 6 months postoperatively showed that good swallowing function was achieved using a palatal augmentation prosthesis.

A case of delivery of healthy infant in breast cancer patient incidentally treated with goserelin acetate and tamoxifen during pregnancy.

In September 2000, a 32-year-old woman presented to our hospital with a right breast mass. In September 2000, she underwent pectoral muscle-preserving mastectomy for the treatment of right breast cancer. Pathologyy results revealed a mucinous carcinoma 27 × 20 × 18 mm in size accompanied by an extensive intraductal component. The tumor was staged as T2 N1M0 stage IIB and found to be estrogen receptor-positive, and 6 cycles of postoperative adjuvant chemotherapy consisting of 5-fluorouracil, epirubicin, and cyclophosphamide were carried out. Goserelin acetate plus tamoxifen was prescribed from April 2001 to March 2005. Since the patient received tamoxifen from April 2005 and eumenorrhea started in June 2006, goserelin acetate plus tamoxifen was started in August 2006. The patient was determined to be 25 weeks pregnant by abdominal ultrasonography in February 2007. This meant that she had been taking goserelin acetate plus tamoxifen for 6 months without realizing she was pregnant. She gave birth to a girl by cesarean section in May 2007. No abnormalities, including anomaly of the genitalia, were seen, and the subsequent growth of the infant was also satisfactory. We here report this case and a brief review of the literature.

[Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma accompanied with cystic change].

A 64-year-old male with throat discomfort visited our hospital, and a chest computed tomography (CT) scan revealed a cystic lesion with a central solid component in the right lung (in the lower lobe, 4.1 x 3.9 cm in diameter). Transbronchial lung biopsy was performed and the lesion was diagnosed as mucosa-associated lymphoid tissue (MALT) lymphoma of the lung. No other lymphoma lesion was detected and it was diagnosed as the stage I-E, and a right lower lobectomy was performed. The cystic lesion derived from alveolus and bronchus destroyed by lymphoma infiltration and it might be caused by air retention due to check-valve mechanism.

[A case of dihydropyrimidine dehydrogenase (DPD) deficiency with severe side effects from UFT/Uzel administration].

5-FU is among the drugs most frequently used in the treatment of gastrointestinal malignancies. Also, it has been reported to reveal severe side effects in the case of a dihydropyrimidine dehydrogenase (DPD) deficiency. A 75-year-old man showed severe nausea and vomiting after administration of UFT/Uzel as adjuvant chemotherapy. Because of severe thrombocytopenia and grade 4 neutropenia, platelet transfusion and G-CSF administration were performed. With time, the leukocyte, neutrophil and platelet count recovered to normal level. We strongly suspected a DPD deficiency from the result of urinary pyrimidine analysis.