Dose-response effect of Montelukast on post-extraction dental socket repair and skeletal phenotype of mice

Bone metabolism and repair are directly regulated by arachidonic acid metabolites. At present, we analyzed the dose-response effects of a selective cysteinyl leukotriene receptor type-1 antagonist during bone repair after tooth extraction and on non-injured skeleton. Sixty-three 129 Sv/Ev male mice composed the groups: C-Control (saline solution); MTK2-2 mg/Kg of Montelukast (MTK) and MTK4-4 mg/Kg of MTK, daily administered by mouth throughout all experimental periods set at 7, 14, and 21 days post-operative. Dental sockets were analyzed by computed microtomography (microCT), histopathology, and immunohistochemistry. Femurs, L5 vertebra and organs were also removed for observation. Blood was collected for plasma bone and liver markers. Histopathology and microCT analysis revealed early socket repair of MTK2 and MTK4 animals, with significant increased BV/TV at days 14 and 21 compared to C. Higher plasma calcium was detected at days 7 and 21 in MTK4 in comparison to C, while phosphate was significantly increased in MTK2 in the same periods in comparison to C and MTK4. No significant differences were found regarding plasma ALP and TRAP, neither for local TRAP and Runx2 immunolabeling at the healing sockets. Organs did not present histological abnormalities. Increased AST levels have been detected in distinct groups and periods. In general, femur phenotype was improved in MTK treated animals. Collectively, MTK promoted early bone formation after tooth extraction and increased bone quality of femurs and vertebra in a time-dose-dependent manner, and should be considered as an alternative therapy when improved post-extraction socket repair or skeleton preservation is required.

Foreign Bodies in Extraction Socket: An Outcome of Negligence and Proposal of a Classification with its Medico-legal Implications

Background

Removal of tooth is just a routine dental surgical practice, where negligence is a must avoidable contingence. Still, few complications may arise during or after the procedure. One of the rare complications is the breakage of surgical instrument or presence of any foreign body (FB) in extraction socket. This may be due to improper handling of a surgical instrument or using substandard tools, which may lead to breakage of the instrument or any negligence by the patient himself. This negligence can be on various levels, like professionals, manufacturers or patients. All these events may cause serious outcomes pertaining to the medicolegal issues.

Purpose

The aim of this study was to classify the negligence in oral surgery for legitimacy with possible management for the retrieval of the FB and discuss various Indian Penal Codes for Medical Negligence according to the Constitution of India and its implications.

Method

Diagnosis and surgical retrieval of FB associated with extraction socket were performed in three cases. Incision, flap reflection, identification of FB and successful retrieval followed by suturing under local anesthesia were achieved. Routine medications were prescribed. The FB were sent for stereomicroscopic examination.

Result

All the patients were followed up after a week, and no complications were observed. Suture removal was carried out, and oral hygiene instructions were given. The FB were found to be piece of lead, broken tip of a dental elevator and broken diamond round bur.

Conclusion

The negligence can occur at any stage, and it has its medicolegal aspects. This negligence can be apprehended in front of the Indian Penal Code for Medical Negligence. Hence, a classification is required to understand and subdivide the negligence to find the legitimacy over the medicolegal implications.

Characterization of progenitor/stem cell population from human dental socket and their multidifferentiation potential

Dental stem cells have many applications in medicine, dentistry and stem cell biology in general due to their easy accessibility and low morbidity. A common surgical manoeuvre after a tooth extraction is the dental socket curettage which is necessary to clean the alveolus and favour alveolar bone healing. This procedure can cause very low morbidity compared to bone marrow collection procedures and the collected material is normally discarded. In order to investigate if the tissue obtained by dental socket curettage after a tooth extraction was a feasible alternative source to isolate human stem cells, we isolated and characterized two different stem cell populations based on STRO-1 and CD146 expression. We were able to collect and grow cells from dental socket of vital and non-vital teeth. Both populations were proliferative, clonogenic and expressed STRO-1, CD146, CD90, NG2, PDGFR-β, which are markers found in stem cells, presented in vitro multiline-differentiation into osteogenic, chondrogenic, and adipogenic tissue, and in vivo transplanted cells formed mineralized tissue. Interestingly, STRO-1⁺ clonogenic cells presented better multidifferentiation than CD146⁺ cells. Our results showed that mesenchymal stem cells can be isolated from the tiny tissue collected by dental socket curettage after vital and non-vital tooth extraction and suggest that STRO-1 is an important marker to be used to sort cells with multidifferentiation capacity.