New World Health Organization classification of odontogenic tumours: impact on the prevalence of odontogenic tumours and analysis of 1231 cases from Turkey

The aims of this study were to describe the frequency of odontogenic tumours (OT) based on the World Health Organization (WHO) 4^th edition of Head and Neck Tumours in Turkey, to compare the results with other regions and to assess the frequency changes of OT worldwide after the new WHO classification. OT were selected from the pathology department's files between 1971-2018. In a total of 1231 OT, 1215 (98.7%) were benign, whereas malignant OT were only 16 cases (1.3%). The three most common tumours were ameloblastoma (n=366, 29.7%), odontoma (n=335, 27.2% both complex and compound types), and odontogenic myxoma (n=190, 15.4%), respectively. After the 2017 classification, the decrease of OT frequency was found among 20%-42% in the selected epidemiological series because of re-classification of some lesions. The pattern of incidence in the Turkish population is similar to that in other populations. However, there are some differences in the frequency of the tumour types. It is obvious that the relative frequency of odontogenic tumours worldwide will change based on the new classification. It should be kept in mind that this is not a real decrease of OT cases. These marked changes in the frequency and prevalence of OT is just related to reclassification of some entities.

Stafne bone defect in the anterior mandible

Lingual mandibular bone defect, also known as Stafne bone cavity, is mostly seen in the posterior portion of the mandible. Cavities in the anterior region are very unusual, with around 50 cases reported in the English literature. They are often asymptomatic and found during routine radiographic examinations. This article describes a case of anterior Stafne bone cavity in a 56-year-old male patient.

The effects of dimethyl sulfoxide on the acute phase of experimental acid and alkali corrosive esophageal burns

BACKGROUND, AIM

The aim of this study was to investigate the effects of dimethyl sulfoxide (DMSO) on the acute phase of experimental corrosive esophageal burns.

MATERIALS AND METHODS

Fifty male rats were allocated into five groups (control, acid burn, alkali burn, acid burn + DMSO and alkali burn + DMSO) of ten rats each. Acid and alkali burns were creating by burning the distal esophagus with 1 N hydrochloric acid and 50% sodium hydroxide solution, respectively. DMSO was applied intraperitoneally at 15 minutes after burn creation and then every 12 hours for four days. All animals were sacrificed at the end of the 7th day. Histopathological changes in esophageal tissue were scored by a single investigator who was blind to the burn group.

RESULTS

Application of DMSO resulted in a significant decrease in the severity of acute tissue damage as measured by macroscopic and microscopic assessments in both the acidic and alkaline esophagitis groups. The increased immunohistochemical Ki-67 proliferation index was significantly suppressed in the DMSO-treated alkaline esophagitis group, p < 0.05. Furthermore, the immunoreactivity of nuclear factor kappa B (NF-kB) was significantly reduced in both the acid and alkali DMSO-treated groups, p < 0.05.

CONCLUSIONS

DMSO reduced the acute phase symptoms and decreased the severity of tissue damage in both acidic and alkaline corrosive esophagitis.

Intraosseous lipoma of the mandible: a case report and review of the literature

Intraosseous lipoma is a benign tumor of the bone. It is mostly seen in the metaphyses of the long bones and calcaneus. There are few documented cases of intraosseous lipomas in the jaw. Clinically, the lesion is usually silent and radiologically it appears as a radiolucent area rarely including some radio-opacities. Diagnosis is based on clinical, radiological and histopathological features. Surgical removal of the lesion is the recommended treatment. The authors report a rare case of an intraosseous mandibular lipoma in a 45-year-old female, and review previously documented cases in the English literature. The histopathological and radiological features of the lesion are emphasized.

Osteomyelitis due to arsenic trioxide use for tooth devitalization

AIM

To present a case of osteomyelitis that was caused by the use of arsenic trioxide during root canal treatment in a mandibular left first molar.

SUMMARY

Arsenic was once in common use to devitalize inflammed pulp tissue before root canal treatment. Its prolonged application or leakage leads to toxic effects beyond the pulp tissue, and necrosis of periodontal tissues and supporting alveolar bone has been described. This report presents a case of osteomyelitis resulting from leakage of arsenic trioxide used in pulp devitalization. Sequestrectomy and excision of non-vital alveolar bone was performed to treat the severe tissue necrosis.

KEY LEARNING POINTS

Agents containing arsenic are still employed by some clinicians and may be encountered when patients present with tissue destruction resulting from their use. Dental practitioners should be aware that arsenic paste may diffuse into periodontal tissues through apical, lateral or accessory canals, through perforations and around leaking restorations. Osteomyelitis caused by arsenic trioxide can be treated by a combination of pharmacotherapeutic and invasive surgical methods. Arsenic pastes have no place in endodontic practice.

Odontogenic tumours in Istanbul: 527 cases

We retrieved and analysed the records of 527 odontogenic tumours from a total of 62,565 cases in the department of tumour pathology in the Institute of Oncology, University of Istanbul, from 1971 to 2003. Of these 527 tumours, 521 were benign and 6 were malignant. The most common lesions were ameloblastomas (n=133) followed by odontomas (n=109), odontogenic myxomas (n=83) and others. There were more female patients (n=278, 53%) than male, and nearly half the patients (n=253, 48%) were between the ages of 10 and 29 years. The posterior mandible was the commonest site (n=184, 35%), followed by the premolar area of the mandible (n=98, 19%), and the anterior maxilla (n=84, 16%).

Histologic Analysis of Alveolar Bone Following Guided Bone Regeneration

BACKGROUND

Questions on new bone quality following guided bone regeneration (GBR) with various graft materials and its importance in osseointegration have been raised. This study reports histologic analysis of bone sections from future implant sites at upper and lower jaws that were augmented with bovine porous bone mineral graft material plus a porcine collagen membrane.

METHODS

Due to severe atrophy of the alveolar crest, GBR prior to implant placement was indicated in 11 patients (mean age 45.5 years). Following an average of 7 months of healing, implant placement surgery was performed. Bone sections from implant beds were fixed in formalin, decalcified in sodium citrate and formic acid, and placed in paraffin. Sections 5 to 7 microm thick were prepared, stained with hematoxylin and eosin, and analyzed under light microscopy. Results for 27 implant sites are presented.

RESULTS

Compared to the lower jaw, segments from the upper jaw had a lower percentage of bone and higher percentage of residual material and vascularization.

CONCLUSIONS

Within the limits of this study, we concluded that osteogenesis is completed and the rate of vascularization and osteoclastic activity was reduced by 7 months. Also, the upper jaw significantly differed from the lower jaw in bone formation, vascularization, and the amount of residual material. Thus, the anatomical location of the defect may be as important as the properties of the graft material used in obtaining successful osteogenesis using guided bone regeneration techniques.

Do vitamin E and selenium have beneficial effects on trinitrobenzenesulfonic acid-induced experimental colitis

The balance between oxidant and antioxidant systems may be important in the pathogenesis and/or maintenance of tissue injury in ulcerative colitis. This study was designed to evaluate the effects of vitamin E and selenium supplementations on tissue injury and oxidative stress in trinitrobenzenesulfonic acid-induced ulcerative colitis in rats. Trinitrobenzenesulfonic acid administration severely changed the normal architecture of the colon and significantly increased the levels of malondialdehyde, protein carbonyl, and xantine oxidase (P < 0.001) in the colon homogenates of these rats. Supplementation of selenium to the trinitrobenzenesulfonic acid-treated rats neither improved the histopathological findings nor decreased the levels of malondialdehyde and protein carbonyl. Vitamin E supplementation reduced the levels of malondialdehyde and protein carbonyl but did not improve the colonic lesions. Supplementation of vitamin E + selenium significantly reduced both the severity of colonic lesions and the levels of malondialdehyde and protein carbonyl. In conclusion, we suggest that antioxidants and specific micronutrients may have beneficial effects in the treatment of ulcerative colitis.

Neurinoma in the buccal mucosa

A 14-year-old girl was referred to our clinic with a problem of a painless slow growing lesion for approximately three years. MR imaging findings of lesion was "retention cyst of the salivary gland". Controversially, the histological examination of the total excised specimen was "neurinoma" and that was inconsistent with MR findings. Neural tissue tumors of the oral cavity are rare, however, this diagnosis was confirmed by surgical excision and histopathological examination. There was a rare location of the lesion as well.