3D printing technology to produce intraoral stents for head and neck radiotherapy: A scoping review

INTRODUCTION

Radiotherapy remains one of the main treatments for head and neck cancer; however, it is accompanied by acute and chronic adverse effects. Use of three-dimensional (3D) oral stents to modulate radiation intensity to specific target areas have been developed to minimize these adverse effects. This study aimed to present a scoping review of studies published on 3D printing of oral stents and their clinical applicability.

METHODS

MEDLINE/Pubmed, Scopus, Web of Science and CENTRAL Cochrane data bases were searched, studies selected, and data collected by three independent reviewers up to December 2022. The review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis-Extension for Scoping Reviews (PRISMA-ScR).

RESULTS

The search resulted in 404 studies and 5 articles fulfilled the eligibility criteria and were considered for this review. Three-dimensional printed intraoral stents were produced for 56 patients with indication for radiotherapy. 3D-printed stents were well-tolerated by all tested patients and demonstrated great reproducibility of maxillomandibular relation, required less time for production and lower cost to manufacture. Two studies showed great protection of healthy tissues with 3D-printed stents during radiotherapy.

CONCLUSIONS

Three-dimensional printing is promising for production of intraoral stents, however, more studies are needed to improve the technique and further investigate the safety and prevention of oral toxicities from radiotherapy.

Gingival metastasis of angiosarcoma of the breast as a first manifestation of spreading disease: Case report and review of the literature

BACKGROUND

Angiosarcoma is an aggressive malignant neoplasm of vascular origin. Oral metastases of angiosarcoma are rare and have a non-specific clinical presentation, thus the diagnosis may be challenging.

CASE REPORT

Herein we report a case of a 34-year-old female patient after treatment of a high-grade angiosarcoma of the breast, who presented an asymptomatic bleeding purplish nodule in the maxillary interdental papilla between the first and second premolar. A biopsy was performed, and the histological examination revealed infiltration by malignant neoplasm of epithelioid and fusocellular pattern. Immunohistochemical analysis demonstrated that neoplastic cells were positive for ERG and CD31, and negative for cytokeratins AE1/AE3, confirming the diagnosis of metastatic angiosarcoma. After investigation, multiple metastases were discovered. The patient is under management with chemotherapy and palliative radiotherapy for the bone lesions.

CONCLUSION

Metastases should be considered in the differential diagnosis of oral lesions in patients with a previous history of cancer. Due to the morphology of angiosarcomas, the metastatic lesions may resemble benign vascular lesions, therefore, biopsy is mandatory to exclude malignancy.

Gingival cyst of the adult

The gingival cyst of the adult (GCA) is a rare odontogenic cyst, consisting of 0.3% of all odontogenic cysts. This case report, based on CARE guidelines for case reports, aims to present a case of a 52-year-old female patient with a symptomatic translucent nodule in the upper left anterior gingiva, measuring approximately 6mm. Excisional biopsy was performed, and the histological examination revealed multiple cystic cavities lined by the squamous epithelium of varying thickness with focal areas of nodular thickenings. The presence of clusters of cells with clear cytoplasm within epithelial thickenings was observed. PAS staining was negative in clear cells. The diagnosis of the GCA was established. Despite its rarity, GCA should be considered in the differential diagnosis of gingival lesions. Conservative surgical treatment proved to be effective, with no signs of recurrence.

A rare case of Ewing sarcoma metastasis to the oral cavity

Ewing sarcoma in the head and neck is rare, and metastasis from other bones to the mandible accounts for 0.7% of cases. This report presents a case of oral metastasis in a 24-year-old male patient diagnosed with Ewing sarcoma of the femur (p53 gene mutation and EWSR1-ERG fusion). The chief complaint was numbness in the mandible and pain for 1 month and a hardened, ulcerated exophytic lesion in the right retromolar region. Imaging exams revealed an unspecified thinning of the cortical bone of the inferior alveolar canal in the right mandibular ramus, associated with erosion of the alveolar bone. Histopathological analysis confirmed metastasis of Ewing sarcoma. The patient presented an aggressive disease progression and died 1 month after the oral diagnosis. It is important to recognize the signs and symptoms compatible with rare clinical outcomes, leading to an early diagnosis that can improve patients' quality of life and survival.

Mandible metastasis of small cell lung cancer mimicking a residual cyst

Small cell lung carcinoma (SCLC) is an uncommon tumor characterized by an aggressive behavior with early metastasis, usually to the contralateral lung, liver, brain, and bones. There are only five cases of this particular tumor metastasizing to the oral cavity described in the English literature. We present the case of metastatic SCLC in the mandible with radiographic findings resembling a residual cyst. A 66-year-old man with previous diagnosis and treatment for a SCLC was referred to the Stomatology Department with a history of persistent pain in the mandible 1 year after the inferior right pre-molar tooth extraction. The radiographic exam showed a well-delimited radiolucent area on that extracted tooth’s region resembling a residual cyst. Biopsy was performed yielding the diagnosis of metastatic SCLC. The patient was referred to the clinical oncologist for chemotherapy. Although uncommon, this tumor should be included in the differential diagnosis of jawbone lesions, particularly when the patient presents a previous diagnosis of SCLC.

Amlodipine-induced gingival overgrowth in a child after liver transplant

Drug-induced gingival overgrowth (GO) has been associated with phenytoin, cyclosporine, and calcium channel blocker therapies. This study reports the case of an 11-year-old girl who was referred for evaluation of GO, which had occurred over the last 6 months. Her medical history included a liver transplant due to biliary atresia 3 years ago, immunosuppressive therapy, and hypertension, which is why she was started on a daily intake of amlodipine. The intraoral examination showed generalized GO, and the treatment consisted of a gingivectomy. Subsequently, amlodipine was replaced with captopril and oral hygiene instructions. There was no recurrence of GO after 28 months of follow-up. Although GO may be related to the chronic use of amlodipine, such an association is uncommon in pediatrics, and the treatment consists of the replacement of medication combined with a surgical approach and plaque control.

Head and neck solitary infantile myofibroma: Clinicopathological and immunohistochemical features of a case series

Infantile myofibroma is a rare mesenchymal benign tumor mostly found in the head and neck region. The aim of this study was to describe a small case series of head and neck solitary infantile myofibroma, emphasizing the importance of the histopathological and immunohistochemical features, and the potential diagnostic challenges. For the study, clinical and imaging data were obtained from the medical records. All cases were histologically reviewed, and immunohistochemical analyses were performed to confirm the diagnosis. Four cases of head and neck solitary infantile myofibroma were identified. All patients were females and presented a mean age of 3 years old (ranging from 2 to 6 years). The site of the tumors were the mandible, right cheek, subcutaneous tissue adjacent to basal cortical of the mandible and upper anterior gingiva. No symptoms, such as pain or paresthesia, were reported. Computerized tomography revealed well-delimited tumors. All tumors were positive for vimentin and alpha-smooth muscle actin. All patients underwent surgical excision and no signs of recurrence were observed after long-term follow-up. In summary, head and neck solitary infantile myofibromas are rare and present excellent prognosis. The correlation between clinical, histopathological and immunohistochemical features are essential for a correct diagnosis.

Osteonecrosis Related to Once-Yearly Zoledronic Acid Treatment in an Osteoporotic Patient after Dental Implant

This paper presents a case of osteonecrosis of the jaw related to zoledronic acid (5 mg) administered once yearly to treat osteoporosis. A 79-year-old woman who has been treated for osteoporosis for 5 years with 5 applications of zoledronic acid was referred for evaluation. The patient had been submitted to dental implant placement and there was no osseointegration. On clinical examination, suppuration and exposed bone on the alveolar ridge were observed. Radiographic examination revealed an osteolytic area and bone sequestration. Both clinical and radiological features were suggestive of osteonecrosis. The treatment consisted of surgery to remove the affected bone completely. The patient is asymptomatic at 9 months after surgery. Dentists and oral surgeons should be alert to the possibility of osteonecrosis related to the use of once-yearly injections of zoledronic acid for the treatment of postmenopausal osteoporosis.

Evaluation of low-level laser therapy in the prevention and treatment of radiation-induced mucositis: a double-blind randomized study in head and neck cancer patients

The purpose of this prospective study was to determine the effect of the low-level laser in the prevention and treatment of mucositis in head and neck cancer patients. A total of 70 patients with malignant neoplasms in the oral cavity or oropharynx were evaluated. The patients were randomized into two low-level laser therapy groups: Group 1 (660nm/15mW/3.8J/cm(2)/spot size 4mm(2)) or Group 2 (660nm/5mW/1.3J/cm(2)/spot size 4mm(2)) starting on the first day of radiotherapy. Oral mucositis was assessed daily and weekly using the NCI and WHO scales. Oral pain was scored daily with a visual analogue scale before laser application. The patients in Group 1 had a mean time of 13.5days (range 6-26days) to present mucositis grade II, while the patients in Group 2 had a mean time of 9.8days (range 4-14days) (both WHO and NCI p=0.005). In addition, Group 2 also presented a higher mucositis grade than Group 1 with significant differences found in weeks 2 (p=0.019), 3 (p=0.005) and 4 (p=0.003) for WHO scale and weeks 2 (p=0.009) and 4 (p=0.013) for NCI scale. The patients in Group 1 reported lower pain levels (p=0.004). Low-level laser therapy during radiotherapy was found to be effective in controlling the intensity of mucositis and pain.

A calcified foreign body in the bladder after laparoscopic inguinal hernia repair

In this paper, we report an exceedingly rare complication after laparoscopic inguinal hernioplasty. A 57-year-old man was submitted to transurethral resection of the prostate followed by laparoscopic "bikini mesh" hernia repair. One year later, he presented with miccional irritative symptoms. Ultrasonography showed a vesical intraluminal foreign body and computerized tomography revealed a calcified foreign body on the anterior bladder wall. On reoperation, it was noted that there occurred mesh transfixation of the bladder. The lateral segments were removed and the patient recovered uneventfully. This is a, thus far, unpublished complication of this technique.

Seminal vesicle cyst and ipsilateral renal agenesis

A case of seminal vesicle cyst with ipsilateral agenesis is presented. The embryologic events, clinical symptoms, and diagnosis are discussed, emphasizing the value of sonography and computer tomography in identifying the cyst. Surgical resection is the treatment of choice.

Prolapsed ureterocele

Although rare, the prolapsed ureterocele constitutes a urologic emergency that can rapidly evolve to severe conditions due to congestion and necrosis, and to obstruction of the urinary tract. A simple external resection resolves the emergency, allowing a postoperative investigation of the whole urinary tract to be performed, in order to adequately prepare urinary reconstruction.

Vesical endometriosis

A case is presented of vesical endometriosis treated surgically in a thirty-one-year-old woman who presented with hypogastric pain and a pelvic mass. Echography showed an intravesical tumor, and cystoscopy led to a presumptive diagnosis of bladder endometriosis. The clinical features, diagnosis, and management are discussed, based on a review of the literature.

Ureteral endometriosis

The authors present two cases of ureteral endometriosis. Urinary tract endometriosis has been frequently described affecting mainly the bladder. In the ureter, it is a rare pathology, of difficult identification. Treatment aims at ureteral disobstruction together with eradication of endometrial foci. This is accomplished by surgical, radiotherapeutic and chemotherapeutic means.