A Novel Orthognathic Surgery With a Half-Millimeter Accuracy for the Maxillary Positioning Using Prebent Plates and Computer-Aided Design and Manufacturing Osteotomy Guide.

This retrospective study aimed to assess the accuracy of prebent plates and computer-aided design and manufacturing osteotomy guide for orthognathic surgery. The prebent plates correspondent to the planning model were scanned with a 3-dimensional printed model for guide design and used for fixation. Forty-two patients who underwent bimaxillary orthognathic surgery using computer-aided design and manufacturing intermediate splint with the guide (guided group: 20 patients) or with conventional fixation under straight locking miniplates (SLMs) technique (SLM group: 20 patients) were analyzed. A deviation of the maxilla between the planned and postoperative positions was evaluated using computed tomography, which was taken 2 weeks before and 4 days after the surgery. The surgery time and the infraorbital nerve paranesthesia were also evaluated. The mean deviations in the mediolateral ( x ), anteroposterior ( y ), and vertical directions ( z ) were 0.25, 0.50, and 0.37 mm, respectively, in the guided group, while that in the SLM group were 0.57, 0.52, and 0.82 mm, respectively. There were significant differences in x and z coordinates ( P <0.001). No significant difference in the surgery duration and paranesthesia was seen, suggesting the present method offers a half-millimeter accuracy for the maxillary repositioning without increasing the risk of extending surgery duration and nerve complication.

Synergistic Enhancement of Protein Recruitment and Retention via Implant Surface Microtopography and Superhydrophilicity in a Computational Fluid Dynamics Model.

The exact mechanisms by which implant surface properties govern osseointegration are incompletely understood. To gain insights into this process, we examined alterations in protein and blood recruitment around screw implants with different surface topographies and wettability using a computational fluid dynamics (CFD) model. Compared with a smooth surface, a microrough implant surface reduced protein infiltration from the outer zone to the implant thread and interface zones by over two-fold. However, the microrough implant surface slowed blood flow in the interface zone by four-fold. As a result, compared with the smooth surface, the microrough surface doubled the protein recruitment/retention index, defined as the mass of proteins present in the area per unit time. Converting implant surfaces from hydrophobic to superhydrophilic increased the mass of protein infiltration 2-3 times and slowed down blood flow by up to two-fold in the implant vicinity for both smooth and microrough surfaces. The protein recruitment/retention index was highest at the implant interface when the implant surface was superhydrophilic and microrough. Thus, this study demonstrates distinct control of the mass and speed of protein and blood flow through implant surface topography, wettability, and their combination, significantly altering the efficiency of protein recruitment. Although microrough surfaces showed both positive and negative impacts on protein recruitment over smooth surfaces, superhydrophilicity was consistently positive regardless of surface topography.

A 3-Dimensional Finite Element Analysis of Resected Mandibular Bone to Determine the Most Stable Implant Positions for a Fixed Prosthesis.

This study was conducted to determine the most secure implant positioning on the marginally resected mandible to support a fixed complete denture through finite element analysis. Three or 4 implants were placed at near, middle, or far positions from the resected margin in a simulation model with a symmetrical marginal defect in the mandibular symphysis. The height of the residual bone was 5, 10, or 15 mm. The 4 possible implant patterns for 3 or 4 implants were defined as (1) asymmetrically isolated position 1 to position 2, (2) asymmetrically isolated position 1 to position 3, (3) asymmetrically isolated with greater-length position 1 to position 2, and (4) 2 implants symmetrically positioned on each side of the defect. The von Mises stress in the resected and peri-implant bone with respect to the occlusal force was calculated. Initially, because the peri-implant bone stress around the isolated implant at the near position was greater than at the middle and far positions regardless of the residual bone height, the near position was excluded. Second, the von Mises stress in the resected bone region was >10 MPa when the isolated implant was at the far position, and it increased inversely depending on the bone height. However, the stress was <10 MPa when the isolated implant was placed at the middle position regardless of the bone height, and it was significantly lower compared with the far position and equivalent to the symmetrically positioned implants. Furthermore, the use of a greater-length implant reduced peri-implant bone stress, which was even lower than that of the symmetrically positioned implants. These results suggest that the asymmetrically positioned 3-implant-supported fixed denture, using a greater-length isolated implant, placed neither too close to nor too far from the resected margin, can be an effective alternative to the symmetrically positioned 4-implant-supported fixed denture.

Impact of superselective intra-arterial and systemic chemoradiotherapy for gingival carcinoma; analysis of treatment outcomes and prognostic factors.

BACKGROUND: We compared outcomes and toxicities between concurrent retrograde super-selective intra-arterial chemoradiotherapy (IACRT) and concurrent systemic chemoradiotherapy (SCRT) for gingival carcinoma (GC). METHODS: We included 84 consecutive patients who were treated for non-metastatic GC ≥ stage III, from 2006 to 2018, in this retrospective analysis (IACRT group: n = 66; SCRT group: n = 18). RESULTS: The median follow-up time was 24 (range: 1-124) months. The median prescribed dose was 60 (6-70.2) Gy (IACRT: 60 Gy; SCRT: 69 Gy). There were significant differences between the two groups in terms of 3-year overall survival (OS; IACRT: 78.8, 95% confidence interval [CI]: 66.0-87.6; SCRT: 50.4, 95% CI: 27.6-73.0; P = 0.039), progression-free survival (PFS; IACRT: 75.6, 95% CI: 62.7-85.2; SCRT: 42.0, 95% CI: 17.7-70.9; P = 0.028) and local control rates (LC; IACRT: 77.2, 95% CI: 64.2-86.4; SCRT: 42.0, 95% CI: 17.7-70.9; P = 0.015). In univariate analysis, age ≥ 65 years, decreased performance status (PS) and SCRT were significantly associated with worse outcomes (P < 0.05). In multivariate analysis, age ≥ 65 years, clinical stage IV, and SCRT were significantly correlated with a poor OS rate (P < 0.05). Patients with poorer PS had a significantly worse PFS rate. Regarding acute toxicity, 22 IACRT patients had grade 4 lymphopenia, and osteoradionecrosis was the most common late toxicity in both groups. CONCLUSIONS: This is the first report to compare outcomes from IACRT and SCRT among patients with GC. ALL therapy related toxicities were manageable. IACRT is an effective and safe treatment for GC.

Straight Locking Miniplate Technique Achieves Submillimeter Accuracy of Condylar Positional Change During Bimaxillary Orthognathic Surgery for Patients With Skeletal Class III Malocclusion.

PURPOSE: The straight locking miniplate (SLM) technique is a straightforward method to accurately reposition the maxilla during bimaxillary orthognathic surgery. The present study evaluated the accuracy of the SLM technique in maintaining the condylar position during surgery without the use of a cutting guide. PATIENTS AND METHODS: The present prospective, single-center study was conducted at Yokohama City University between 2016 and 2017 and included patients with skeletal Class III malocclusion. The patients were divided into 2 groups according to the fixation method used for the mandibular segments. The mandibular segments were fixed with miniplates either manually (manual group) or using the SLM technique (SLM group). Computed tomography was performed before and 3 days after surgery to compare the condylar position. The bodily and rotational movements of the condyle were analyzed. RESULTS: The subjects were 18 Japanese patients (36 condyles) who had undergone bilateral set back surgery with Le Fort I osteotomy. The amount of bodily movements in the manual and SLM groups were 1.44 and 0.62 mm, respectively. The degree of rotational movement in the sagittal plane in the manual and SLM groups was 3.33° and 0.23°, respectively. The bodily and rotational movements in the SLM group were significantly smaller than those in the manual group (P < .05 and P < .01, respectively). CONCLUSIONS: These results suggest that use of the SLM technique reduces the risk of condylar positional changes to less than 1 mm during orthognathic surgery without the use of any complex devices or a cutting guide.

Computational Fluid Simulation of Fibrinogen around Dental Implant Surfaces.

Ultraviolet treatment of titanium implants makes their surfaces hydrophilic and enhances osseointegration. However, the mechanism is not fully understood. This study hypothesizes that the recruitment of fibrinogen, a critical molecule for blood clot formation and wound healing, is influenced by the degrees of hydrophilicity/hydrophobicity of the implant surfaces. Computational fluid dynamics (CFD) implant models were created for fluid flow simulation. The hydrophilicity level was expressed by the contact angle between the implant surface and blood plasma, ranging from 5° (superhydrophilic), 30° (hydrophilic) to 50° and 70° (hydrophobic), and 100° (hydrorepellent). The mass of fibrinogen flowing into the implant interfacial zone (fibrinogen infiltration) increased in a time dependent manner, with a steeper slope for surfaces with greater hydrophilicity. The mass of blood plasma absorbed into the interfacial zone (blood plasma infiltration) was also promoted by the hydrophilic surfaces but it was rapid and non-time-dependent. There was no linear correlation between the fibrinogen infiltration rate and the blood plasma infiltration rate. These results suggest that hydrophilic implant surfaces promote both fibrinogen and blood plasma infiltration to their interface. However, the infiltration of the two components were not proportional, implying a selectively enhanced recruitment of fibrinogen by hydrophilic implant surfaces.

EP4-induced mitochondrial localization and cell migration mediated by CALML6 in human oral squamous cell carcinoma.

Lymph node metastasis, primarily caused by the migration of oral squamous cell carcinoma (OSCC) cells, stands as a crucial prognostic marker. We have previously demonstrated that EP4, a subtype of the prostaglandin E2 (PGE2) receptor, orchestrates OSCC cell migration via Ca2+ signaling. The exact mechanisms by which EP4 influences cell migration through Ca2+ signaling, however, is unclear. Our study aims to clarify how EP4 controls OSCC cell migration through this pathway. We find that activating EP4 with an agonist (ONO-AE1-473) increased intracellular Ca2+ levels and the migration of human oral cancer cells (HSC-3), but not human gingival fibroblasts (HGnF). Further RNA sequencing linked EP4 to calmodulin-like protein 6 (CALML6), whose role remains undefined in OSCC. Through protein-protein interaction network analysis, a strong connection is identified between CALML6 and calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), with EP4 activation also boosting mitochondrial function. Overexpressing EP4 in HSC-3 cells increases experimental lung metastasis in mice, whereas inhibiting CaMKK2 with STO-609 markedly lowers these metastases. This positions CaMKK2 as a potential new target for treating OSCC metastasis. Our findings highlight CALML6 as a pivotal regulator in EP4-driven mitochondrial respiration, affecting cell migration and metastasis via the CaMKK2 pathway.

Actinomyces-associated calcifications in a dentigerous cyst of the mandible.

Actinomyces-associated lesions in the jaw, such as radicular cyst and osteomyelitis, have been reported by many authors. The lesions are caused by infection from peripheral sites and can be seen to contain Actinomyces druses on pathologic examination. To our knowledge, no previous reports have described Actinomyces-associated calcification in the jaw, although the lesions in the jaw often include druses. We report here a rare case of Actinomyces-associated calcifications in a dentigerous cyst of the mandible.

Mandibular Ewing sarcoma with chromosomal translocation t(21;22)(q22;q12).

Ewing sarcoma (ES) is a primary bone malignant neoplasm and is the second most common primary malignancy of the bone found in childhood and adolescence after osteosarcoma. ES has an annual frequency in the population younger than 20 years of approximately 2.9 per million. ES occurs most frequently in the long bones of the extremities and pelvis and very rarely in the jaw. Recently, it was revealed that chromosomal translocation t(11;22)(q24;q12), which fuses the EWS gene on chromosome 22 and the FLI-1 gene on chromosome 11, occurs in most cases of ES. We report here a rare case of mandibular ES in a 10-year-old child with chromosomal translocation t(21;22)(q22;q12) in which the EWS gene is fused with the ERG gene on chromosome 21.

Accuracy and influencing factors of maxillary and mandibular repositioning using pre-bent locking plates: a prospective study.

In-house repositioning methods based on three-dimensional (3D)-printing technology and the use of pre-bent plates has been gaining popularity in orthognathic surgery. However, there remains room for further improvement in methods and investigations on clinical factors that affect accuracy. This single-centre, prospective study included 34 patients and aimed to evaluate the accuracy and factors influencing maxillary and mandibular repositioning using pre-bent locking plates. The plates were manually pre-bent on the 3D-printed models of the planned position, and their hole positions were scanned and reproduced intraoperatively with osteotomy guides. The accuracy of repositioning and plate-hole positioning was calculated in three axes with the set landmarks. The following clinical factors that affect repositioning accuracy were also verified: deviation of the plate-hole positioning, amount of planned movement, and amount of simulated bony interference. The median deviations of the repositioning and hole positioning between the preoperative plan and postoperative results were 0.26 mm and 0.23 mm, respectively, in the maxilla, and 0.69 mm and 0.36 mm, respectively, in the mandible, suggesting that the method was highly accurate, and the repositioning concept based on the plate hole and form matching was more effective in the maxilla. Results of the correlation test suggest that large amounts of bony interference and plate-hole positioning errors in the up/down direction could reduce mandibular repositioning accuracy.

Influence of the Oral Health Assessment Tool Score on Survival of Patients With Esophageal Cancer.

BACKGROUND/AIM: We investigated the influence of the preoperative Oral Health Assessment Tool (OHAT) score on the outcomes of patients with esophageal cancer after curative surgery. PATIENTS AND METHODS: This study included 90 patients with esophageal cancer who underwent curative surgery and who were screened with the OHAT between 2008 and 2021. The OHAT consists of eight categories with three possible scores. The risk factors for 5-year overall survival (OS) and recurrence-free survival (RFS) were identified. RESULTS: Patients were divided into healthy (n=42) and unhealthy (n=48) groups. The OHAT score was identified as a significant risk factor for postoperative pneumonia (11.9% vs. 43.8%, p=0.001) and postoperative hospital stay (20.5 days vs. 50.1 days, p=0.042). The 5-year OS rate after surgery was 71.2% in the healthy group and 43.2% in the unhealthy group, which was a significant difference (p=0.015). A multivariate analysis showed that a high OHAT score was a significant independent factor for 5-year OS (p=0.034). CONCLUSION: The OHAT score was a useful prognostic marker in patients who underwent curative surgery for esophageal cancer. To improve the oncological outcomes of patients with esophageal cancer, it is necessary to carefully plan perioperative oral/dental care using the OHAT score.

Analysis of carotid artery deformation in different head and neck positions for maxillofacial catheter navigation in advanced oral cancer treatment.

BACKGROUND: To improve the accuracy of catheter navigation, it is important to develop a method to predict shifts of carotid artery (CA) bifurcations caused by intraoperative deformation. An important factor affecting the accuracy of electromagnetic maxillofacial catheter navigation systems is CA deformations. We aimed to assess CA deformation in different head and neck positions. METHODS: Using two sets of computed tomography angiography (CTA) images of six patients, displacements of the skull (maxillofacial segments), C1-C4 cervical vertebrae, mandible (mandibular segment), and CA along with its branches were analyzed. Segmented rigid bones around CA were considered the main causes of CA deformation. After superimposition of maxillofacial segments, C1-C4 and mandible segments were superimposed separately for displacement measurements. Five bifurcation points (vA-vE) were assessed after extracting the CA centerline. A new standardized coordinate system, regardless of patient-specific scanning positions, was employed. It was created using the principal axes of inertia of the maxillofacial bone segments of patients. Position and orientation parameters were transferred to this coordinate system. CA deformation in different head and neck positions was assessed. RESULTS: Absolute shifts in the center of gravity in the bone models for different segments were C1, 1.02 ± 0.9; C2, 2.18 ± 1.81; C3, 4.25 ± 3.85; C4, 5.90 ± 5.14; and mandible, 1.75 ± 2.76 mm. Shifts of CA bifurcations were vA, 5.52 ± 4.12; vB, 4.02 ± 3.27; vC, 4.39 ± 2.42; vD, 4.48 ± 1.88; and vE, 2.47 ± 1.32. Displacements, position changes, and orientation changes of C1-C4 segments as well as the displacements of all CA bifurcation points were similar in individual patients. CONCLUSIONS: CA deformation was objectively proven as an important factor contributing to errors in maxillofacial navigation. Our study results suggest that small movements of the bones around CA can result in small CA deformations. Although patients' faces were not fixed properly during CT scanning, C1-C4 and vA-vE displacements were similar in individual patients. We proposed a novel method for accumulation of the displacement data, and this study indicated the importance of surrounding bone displacements in predicting CA bifurcation.

A simple method with a sterilized surgical glove for removal of stripped screw.

In oral and maxillofacial surgery such as orthognathic surgery and open treatment of maxillofacial fracture, plate fixation is commonly performed. Although the removal of titanium miniplates is controversial, the plates are removed routinely or symptomatically. By excessive torque during the screw removal, stripping or breaking of screw heads may occur. Although miniplates and screws are used with angled screwdrivers for osteosynthesis in bilateral sagittal split osteotomy (BSSO) or open treatment of mandibular angle or subcondylar fracture, the removal of a damaged screw, especially with the angled screwdriver, is very difficult. Therefore, we report a simple method with a sterilized surgical glove for removal of the stripped screw.

Oral candidiasis caused by ciclesonide in a patient with COVID-19 pneumonia: A case report and literature review.

Steroid has recently been reported as a treatment for new coronavirus disease (COVID-19). The incidence of oropharyngeal candidiasis due to the inhaled steroid ciclesonide is lower than that due to other inhaled steroids. We report the first case of oral candidiasis with COVID-19 pneumonia using ciclesonide. A 75-year-old man was hospitalized for COVID-19 pneumonia. After admission, an oral combination of lopinavir/ritonavir was administered, and ciclesonide was inhaled for 7 days. On the 14th day of hospitalization, white plaque was found in his oral mucosa. Candida albicans was identified by oral bacterial tests, and amphotericin B was initiated. On the 35th hospital day, negative result for C. albicans was confirmed. Intraoral monitoring and intervention by dental care workers are considered important for the prevention of infectious complications induced by corticosteroids.

Sentinel lymph node mapping of clinically N0 early oral cancer: a diagnostic pitfall on CT lymphography.

OBJECTIVE: The purpose of this study was to reevaluate preoperative computed tomography lymphography (CTL) and enhanced CT images during follow-up to clarify whether SLNs enhanced by CTL were identified accurately before primary surgery with sentinel lymph node biopsy (SLNB) for clinically N0 early oral cancer. METHODS: Thirty two early oral cancer patients without cervical lymph node metastasis were enrolled in this study. To clarify whether SLNs enhanced by CTL were identified accurately before primary surgery with SLNB, we reevaluated preoperative CTL and enhanced CT images during follow-up in all patients. RESULTS: SLNs were detected by CTL in 31 of 32 patients (96.9%). During follow-up after primary surgery with SLNB, 4 of 27 patients without SLN metastasis had occult neck metastasis. Of the 4 patients, only 1 patient with cancer of floor of the mouth had overlooking of SLN, and the overlooking rate of SLN was 3.1%. The overlooked small SLN (2.9 × 3.3 × 3.1 mm) was located at contralateral level IB. The CT numbers before, 2, 5, 10 min after iopamidol injection, were 33 HU, 37 HU, 62 HU, 52 HU, respectively. The CT numbers of overlooked SLN 5 and 10 min after the injection was higher than CT images scanned before the iopamidol injection. CONCLUSIONS: The enhancement of SLNs in CTL images after iopamidol injection should be compared sufficiently with CT images before iopamidol injection to avoid overlooking of SLNs in N0 early oral cancer.

Endoscopically-assisted intraoral resection of osteochondroma of the mandibular condyle with a piezoelectric surgical device.

Background: Osteochondromas of the mandibular condyle show facial asymmetry and malocclusion. Because condylar osteochondromas are generally resected in a preauricular approach with risks of facial nerve injury and visible scar, the authors report endoscopically assisted intraoral resection of osteochondroma of the mandibular condyle with a piezoelectric surgical device.Case presentation: A 38-year-old woman presented with malocclusion and facial asymmetry caused by deviation of the chin to the left. Computed tomography showed a hyperdense, well-circumscribed mass arising from the medial aspect of the right mandibular condyle with resorption of the skull base. The patient underwent an endoscopically-assisted intraoral condylectomy with a piezoelectric surgical device. The postoperative course was uneventful without trismus, malocclusion, or facial asymmetry, and there was no recurrence 4 years after surgery.Conclusion:Endoscopically assisted intraoral resection of osteochondroma of the mandibular condyle with a piezoelectric surgical device is a minimally invasive and safe surgery.

Actinomycotic osteomyelitis with proliferative periostitis arising in the mandibular ramus: an unusual case with spontaneous bone regeneration after coronoidectomy.

Actinomycotic osteomyelitis is an aggressive and persistent disease capable of invading and destroying bone, and chronic osteomyelitis with proliferative periostitis represents new bone formation with periosteal reaction. We report a rare case of actinomycotic osteomyelitis with proliferative periostitis arising in the mandibular ramus and spontaneous bone regeneration after coronoidectomy. A 14-year-old girl was referred for swelling in the right parotid-masseteric region and severe trismus. Contrast-enhanced CT revealed that heterogenous enhancement of the right masseter muscle, and a reactive bone formation over the lateral cortex of the right mandibular ramus and osteolysis of the condyle were seen in plain CT. MRI showed that the mandibular ramus was a low-signal intensity and the reactive bone on the ramus was signal intensity similar to muscle on T1-weighted images. The lesion was clinically and radiologically diagnosed as chronic osteomyelitis of the mandibular ramus. However, a biopsy was performed intraorally under general anesthesia to rule out a malignant bone tumor, and pathological examination showed fibrous bone and Actinomyces druses. Finally, the lesion was diagnosed as actinomycotic osteomyelitis with proliferative periostitis. She underwent image-guided intraoral removal of impacted right third molar and reactive proliferative bone on the right mandibular ramus under general anesthesia. To improve trismus, coronoidectomy also was performed. After the discharge, AMPC was administrated intraorally for 7.5 months. Postoperative panoramic radiograph and CT showed the right mandibular angle resorption and coronoid process regeneration. There was no recurrence of mandibular osteomyelitis 7 years after surgery.

Applicability of a single camera-based catheter navigation system using teeth arch as an anatomical landmark for superselective intraarterial infusion in advanced oral cancer treatment.

Superselective intraarterial infusion chemoradiotherapy is a modality of oral cancer therapy in which the artery feeding the tumor is catheterized. 3D information about the carotid artery is required to enable the surgeon to judge whether to advance, retract, or rotate the catheter. For this purpose, we proposed and conducted a model experiment to assess a new method of catheterization that applies a tracking system using registration with a monocular camera using the maxillary arch as the anatomical landmark. In this method, the preoperative 3D computer tomography angiographic image of the carotid artery that the catheter will be passed through is overlaid on the 2D video image. The mean TRE was 0.96 ± 0.36 mm and 0.88 ± 0.31 mm and 1.12 ± 0.46 mm when images were registered with the anterior and posterior teeth as the landmarks, respectively; the difference was not significant (p = 0.21). This tracking system that enables markerless registration simply by taking images of the maxillary anterior teeth with a single camera was convenient and effective for catheterization. In this study, we propose the new application of this tracking system and a novel method of catheterization for superselective intraarterial infusion chemoradiotherapy for oral cancer. In retrograde superselective intraarterial catheterization, a catheter is inserted into a tumor-feeding artery originating from the external carotid artery (ECA) (the lingual artery [LA], facial artery [FA], or maxillary artery [MA]). Because the maxillary dentition is located near the external carotid artery, we focused on real-time markerless registration using maxillary dentition fixed to the skull.

UV-Mediated Photofunctionalization of Dental Implant: A Seven-Year Results of a Prospective Study.

Our objective was to evaluate the seven-year results of photofunctionalized implants placed in regular, complex, and cancer-related cases. This study was a prospective, single-center study. Photofunctionalization was performed immediately prior to implantation with Ultraviolet (UV) light for 15 minutes. The success rate of each patient group and the influential factors on implant failure were analyzed. Seventy implants in 16 patients were included. Four implants were left submerged (sleep). The seven-year success rate of 30 implants in regular cases and 21 implants in complex cases was 100%. The success rate of 15 implants in cancer-related cases was 22.2%, in which implants were placed in resection or reconstructed sites with or without pre- or postoperative radiation history. Implant stability quotient (ISQ) values increased at second-stage surgery by 3.2 in regular cases and by 21.9 in complex cases, while it decreased by -3.5 in cancer cases. Multivariate analysis indicated that bone quality, location, and cancer resection significantly influenced implant failure. A very reliable seven-year success rate was obtained by UV-photofunctionalized implants in regular and complex cases, even with significant site-development procedures. However, the success rate in cancer cases was significantly and remarkably lower, suggesting remaining challenges of pathophysiologically compromised conditions, such as bone resection, segmental defect, and radiation.

Proton beam therapy combined with retrograde intra-arterial infusion chemotherapy for an extremely rapid growing recurrent ameloblastic carcinoma: A case report.

Ameloblastic carcinoma (AC) is a very rare malignant odontogenic tumor. Although surgical resection is generally performed, treatment approaches have not been established for recurrent cases. Chemotherapy and radiotherapy are positioned as adjunctive therapies, and few studies investigated definitive non-operative therapy. We present the case of a 71-year-old male with recurrent secondary-type AC arising from the right maxilla, who was treated with proton beam therapy (PBT; 71.4 Gy relative biological effectiveness in 32 fractions) combined with continuous intra-arterial infusion of cisplatin (40 mg/m2) and docetaxel (8 mg/m2). The patient experienced acute grade 3 mucositis, dermatitis and neutropenia, which were resolved within 3 months of treatment. Late adverse events were grade 1 skin atrophy, and grade 2 right optic nerve disorder and retinopathy. After ~8 years of treatment, the patient died from another cause but did not experience any relapse or metastasis during the follow-up period of 94 months. To the best of our knowledge, this is the first report of recurrent AC treated with PBT and intra-arterial infusion chemotherapy without any severe late adverse events. This combination therapy approach may be considered as an effective therapeutic option for inoperable AC.