Publication date: February 2019
Source: Archives of Oral Biology, Volume 98
Author(s): Jia Yu, Eerika Mursu, Matleena Typpö, Sakari Laaksonen, Hanna-Marja Voipio, Paula Pesonen, Aune Raustia, Pertti Pirttiniemi
Publication date: Available online 22 November 2018
Source: Archives of Oral Biology
Author(s): Stéphane J. Montuelle, Rachel A. Olson, Hannah Curtis, JoAnna V. Sidote, Susan H. Williams
This study evaluates the effect of unilateral lingual sensory loss on the spatial and temporal dynamics of jaw movements during pig chewing.
X-ray Reconstruction of Moving Morphology (XROMM) was used to reconstruct the 3-dimensional jaw movements of 6 pigs during chewing before and after complete unilateral lingual nerve transection. The effect of the transection were evaluated at the temporal and spatial level using Multiple Analysis of Variance. Temporal variables include gape cycle and phase durations, and the corresponding relative phase durations. Spatial variables include the amplitude of jaw opening, jaw yaw, and of mandibular retraction-protraction.
The temporal and spatial dynamics of jaw movements did not differ when chewing ipsi-versus contralateral to the transection. When compared to pre-transection data, 4 of the 6 animals showed significant changes in temporal characteristics of the gape cycle following the transection, irrespective of chewing side, but the specific response to the lesion was highly dependent on the animal. On the other hand, in affected individuals the amplitude of jaw movements was altered similarly in all 3 dimensions: jaw opening and protraction-retraction increased whereas jaw yaw decreased.
The variable impact of this injury in this animal model suggests that individuals use different compensatory strategies to adjust or maintain the temporal dynamics of the gape cycle. Because the amplitude of jaw movements are more adversely affected than their timing, results suggest that maintaining the tongue-jaw coordination is critical and this can come at the expense of bolus handling and masticatory performance.
Publication date: Available online 22 November 2018
Source: Archives of Oral Biology
Author(s): K.A. Fukushima, M.M. Marques, T.K. Tedesco, G.L. de Carvalho, F. Gonçalves, H. Caballero-Flores, S. Morimoto, M.S. Moreira
The aim of this systematic review was to evaluate the most appropriate hydrogel scaffold type (natural, synthetic or hybrid) to be applied with stem cells for dental pulp regeneration. The findings should help clinicians make an informed choice about the appropriate scaffold to be applied for this approach.
Three electronic databases were searched (Medline, Web of Science and Scopus). The review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA).
From 4,990 potentially relevant studies initially identified, 18 papers fulfilled the eligibility criteria and were considered for this review. Natural scaffolds were applied in most studies. Collagen was the most studied scaffold. In 5 of 10 studies, only growth factors were added to the constructs. Even without growth factors, these scaffolds containing stem cells were able to support the formation of dentin. The synthetic scaffolds were the least studied. Only 4 studies were selected, and in 3 of them, the same scaffold (Puramatrix) was evaluated. Puramatrix by itself was unable to form dental pulp when dental pulp stem cells were not present. Synthetic and hybrid hydrogels were unable to attract stem cells from the host. The presence of growth factors in these constructs seems to be of relevance since dental pulp tissue formation was achieved only when the hybrid scaffold was applied with growth factors.
All types of hydrogel-based scaffolds, when containing mesenchymal stem cells, are able to form connective tissue with different degrees of similarity to dental pulp. However, current data is too heterogeneous to compare and identify the advantages of any specific scaffold.
Publication date: Available online 22 November 2018
Source: Archives of Oral Biology
Author(s): Wbeimar Andrey Rivera-PĂ©reza, AndrĂ©s Felipe YĂ©pes-PĂ©rez, Maria Cecilia MartĂnez-PabĂłna
This study identified potential inhibitory compounds of the phosphoenolpyruvate-sugar
Phosphotransferase system of S. mutans, specifically enzyme II mannose transporter (EIIMan) in its subunits IIA, IIB and IIC by means of a selection protocol and in silico molecular analysis.
Intervening the phosphotransferase system would compromise the physiological behavior and the pathogenic expression of S. mutans, and possibly other acidogenic bacteria that use phosphotransferases in their metabolism—making the phosphotransferase system a therapeutic target for the selective control of acidogenic microorganisms in caries control.
Several computational techniques were used to evaluate molecular, physicochemical, and toxicological aspects of various compounds. Molecular docking was used to calculate the binding potential (ΔG) between receptor protein subunits and more than 836,000 different chemical compounds from the ZINC database. Physicochemical parameters related to the compounds' pharmacokinetic and pharmacodynamic indicators were evaluated, including absorption, distribution, metabolism, excretion, and toxicity (ADMET), and chemical analysis characterized the compounds structures.
Thirteen compounds with EII binding potential of the phosphotransferase system of S. mutans and favorable ADMET properties were identified. Six spirooxindoles and three pyrrolidones stand out from the found compounds; unique structural characteristics of spirooxindoles and pyrrolidones associated with various reported biological activities like anti-microbial, antiinflammatory, anticancer, nootropic, neuroprotective and antiepileptic effects, among other pharmacological effects with surprising differences in terms of mechanisms of action.
Following studies will provide more evidence of the action of these compounds on the phosphotransferase system of S. mutans, and its possible applications.
Publication date: Available online 23 November 2018
Source: Journal of Cranio-Maxillofacial Surgery
Author(s): Mohammad Zandi, Arash Dehghan, Faezeh Gheysari, Leila Rezaeian, Naser Mohammad Gholi Mezerji
To evaluate the effects of short-term teriparatide administration on healing of autologous bone graft in mandibular critical-size defects.
and methods: A 5-mm mandibular bone defect was created and iliac bone graft was harvested in 135 rats. Rats were randomly divided into 3 groups of negative control (NC), control (C), and study (S). In groups S and C, iliac graft was placed in defect and 2 ÎĽg/kg/day teriparatide or saline, respectively, was administered for 20 days. In group NC, iliac graft was not transferred to the defect and saline was injected for 20 days. Twenty, 40, and 60 days after surgery, 15 rats in each group were euthanized and the healing process was histologically evaluated and scored using a grading system (1 to 6).
In group NC, defects did not heal or were predominantly filled with fibrous tissue. At day 20, bone defects in both C and S groups contained a large area of graft particles, numerous collagen fibers and some areas of new trabeculae. At the day 40, defects in group S showed a larger bone graft area, more new bone formation, smaller connective tissue area, and a higher healing score compared to group C (P<0.05). At day 60, most of the defect in group S was filled with graft particles and mature bone while in group C, new trabecular bone formation was still underway (P<0.05).
Teriparatide therapy improves healing of bone defects reconstructed with autograft by reducing bone graft resorption and enhancing new bone formation and maturation.
Publication date: Available online 22 November 2018
Source: Journal of Cranio-Maxillofacial Surgery
Author(s): Kai Qian, Kai Guo, Xiaoke Zheng, Wenyu Sun, Tuanqi Sun, Lili Chen, Ding Ma, Yi Wu, Qinghai Ji, Zhuoying Wang
To evaluate whether elective neck dissection (END) was beneficial for cN0 patients with salivary gland carcinoma.
The rates of regional failure-free survival and disease-free survival were calculated using Kaplan–Meier methods and Cox models. The risk factors for occult lymph node metastasis (OLNM) in cN0 patients undergoing END was analyzed using logistic regression. A nomogram was formulated to calculate the estimated probability of OLNM.
Neck dissection was performed in 84 patients (43.3%). OLNM was detected in eight of the patients who underwent END. During the follow-up period, regional recurrences involving cervical lymph nodes were found in 10 patients. Cox model analysis revealed that neck dissection was not related to regional failure-free survival and disease-free survival. Logistic regression analysis revealed that older age, neural symptoms, and positive adjacent lymph nodes were associated with OLNM. A nomogram comprising age, neural symptoms, and adjacent lymph nodes was developed to predict the risk of OLNM.
The incidence of OLNM was low in cN0 patients after detailed preoperative evaluations. There was no strong evidence supporting END as a conventional therapy in cN0 patients with salivary cancers. Our nomogram is a simple and practical instrument for strengthening the prediction of OLNM.
Publication date: Available online 22 November 2018
Source: Journal of Cranio-Maxillofacial Surgery
Author(s): Suvi Alaluusua, Leena Turunen, Anne Saarikko, Ahmed Geneid, Junnu Leikola, Arja Heliövaara
International Journal of Environmental Research and Public Health IJERPH, Vol. 17, Pages 6976: Overcoming Barriers to Agriculture Green T...
