Cansu Alpaslan

Tissue reaction to three subcutaneously implanted local hemostatic agents

Soft tissue response to three subcutaneously implanted local hemostatic agents; oxidised regenerated cellulose (Surgicel), gelatin sponge (Spongostan) and collagen sponge (Hemostagen) were evaluated histopathologically 7, 14, 21, 30 and 45 days following their implantation in rats. The results showed that all materials were well tolerated by soft tissues. These materials neither seemed to impair nor contribute to wound healing.

Long-term evaluation of recombinant human bone morphogenetic protein-2 induced bone formation with a biologic and synthetic delivery system

The efficacy of microspheres made of polylactic acid polyglycolic acid copolymer mixed with blood clot as a delivery system for recombinant human bone morphogenetic protein-2 (rhBMP-2) was evaluated and the long term behaviour of rhBMP-2 in rats was studied. Twenty micro grams of rhBMP-2 in 200 microliter carrier (blood coagulum and polylactic acid polyglycolic acid porous microspheres) were implanted subcutaneously over both sides of the chest muscles in 40 5-week-old male Long Evans rats. The control group were implanted with carrier alone. Specimens were retrieved after 3 days and weekly for 9 weeks. Outcome was measured by signs of bone formation on low power radiographs, and signs of bony growth on histological examination. There were no signs of foreign body or inflammatory reactions to the carrier in either group. In the experimental group signs of bone formation had started to appear by the end of the first week, and there was a gradual increase in both radio-opacity and size during the observation period. Histologically the bony growth was beginning to mature by 4 weeks and was fully mature by 7-9 weeks. In contrast there was no sign of cartilage or bone formation in the control group and the carrier had resorbed by 4-6 weeks. It is concluded that rhBMP-2 implanted in a carrier consisting of blood clot and porous microspheres made of polylactic acid polyglycolic acid induces rapid proliferation of mesenchymal cells that lead to formation of cartilage and bone by 7 days which had matured by 9 weeks. rhBMP-2 in this carrier may be useful clinically because of its capacity to induce early formation of bone.

Osteoclast differentiation in ectopic bone formation induced by recombinant human bone morphogenetic protein 2 (rhBMP-2).

Osteoclast differentiation in the process of ectopic bone formation induced by recombinant human bone morphogenetic protein 2 (rhBMP-2) was examined to clarify the relationship between osteoclast development and rhBMP-2-induced bone formation. A combination of rhBMP-2 with a porous microsphere (PMS) and blood clot was implanted subcutaneously on the bilateral chest muscles of rats. Tartrate-resistant acid phosphatase (TRAPase) activity, cathepsin K (cath K), and calcitonin receptor (CTR), as markers of osteoclasts and their precursors, were examined using enzyme and immunohistochemical analysis up to 7 days after implantation. Mononuclear cells positive for TRAPase, cath K, and CTR first appeared on day 3 in connective tissue surrounding the PMS after implantation of rhBMP-2. Simultaneously, alkaline phosphatase activity became detectable in mesenchymal cells in the connective tissue. Electron microscopy demonstrated some mononuclear cells with abundant mitochondria and poorly developed rough endoplasmic reticulum in the proximity of mesenchymal cells. However, there was no evidence of cartilage or bone matrix formation on day 3. Osteoclasts in various stages of development, classified by the pattern of immunoreactivity for cath K, were observed by day 7. The polarized intracellular distribution of cath K was found only in osteoclasts attached to bone matrix. In conclusion, we have demonstrated for the first time the appearance of osteoclast precursors before bone matrix formation induced by rhBMP-2, suggesting that bone matrix is not a prerequisite for osteoclast precursor recruitment. Furthermore, we suggest that differentiation into polarized functional osteoclasts is accomplished when the osteoclasts attach to the bone matrix.

Does the use of soft or hard splints affect the short-term outcome of temporomandibular joint arthrocentesis?

Arthrocentesis is an effective treatment modality for temporomandibular joint (TMJ) disc displacement without reduction (DDw/oR), especially in patients who do not respond to non-surgical methods, and is nowadays regarded as a first-line treatment. Soft and hard stabilizing splints have also been used to treat TMJ disorders, but no data are available regarding the use of splints following arthrocentesis. The aim of this study was to compare the effect of the use of soft or hard stabilizing splints versus no appliance following TMJ arthrocentesis on the prognosis of the treatment. Forty-five patients with DDw/oR were included in the study. Pain was measured on a visual analog scale, and maximal mouth openings, lateral jaw movements and tenderness were recorded before arthrocentesis. Following arthrocentesis hard splints were fabricated for 22 patients, soft splints for 9 patients, and 14 patients without any splint served as controls. All the measurements were repeated 1 day, 1 month, 3 months and 6 months after arthrocentesis. Improvement in mouth opening was significant as well as decrease in pain in all groups regardless of the use of splints (P<0.05). Arthrocentesis alone is a successful procedure in the treatment of DDw/oR; the use of splints as an additional therapy does not affect the short-term prognosis.

Clinical and radiographic evaluation of the efficacy of platelet-rich plasma combined with hydroxyapatite bone graft substitutes in the treatment of intra-bony defects in maxillofacial region

Abstract Objective. The aim of this study is to evaluate the efficacy of platelet-rich plasma (PRP) clinically and radiographically when combined with bovine derived hydroxyapatite (HA) bone grafting materials and resorbable collagen membranes for the treatment of intra-bony defects frequently seen at the distal aspect of mandibular second molars following the surgical extraction of fully impacted mandibular wisdom teeth. Study design. Eighteen patients were scheduled for post-operative visits at 1, 3 and 6 months post-operatively, probing depths were measured and digital panoramic radiographs were taken. Results. There were no significant differences on probing depths among two groups. Radiographic assessment also showed no significant difference among groups at 1st and 6th month intervals, while 3 months post-operatively the amount of radiographic density at the PRP side was significantly higher. Conclusion. Combined use of PRP and bovine-derived HA graft materials for the treatment of intra-bony defects might be an appropriate approach when the main goal is providing earlier bone regeneration.

Bone reaction to subperiosteally implanted hydroxyapatite/collagen/glycosaminoglycans and coral in the guinea pig

Tissue reactions and new bone formation at 30, 60, and 90 days after the subperiosteal implantation of hydroxyapatite/collagen/glycosaminoglycans and blocks of coral in 18 guinea pigs were evaluated histologically with the use of polarized light and light microscopy. Animals implanted with coral showed new bone formation at each time interval and resorption of coral was observed. Histopathologic evaluation of hydroxyapatite/collagen/glycosaminoglycans implants revealed no evidence of new bone formation and the hydroxyapatite particles were surrounded by fibrous connective tissue.

Comparative Efficacy of Four Muscle Relaxants on Signs and Symptoms of the Myofascial Pain Syndrome Associated with Temporomandibular Disorders: A Randomized Clinical Trial

Objective This study was undertaken to evaluate the comparative efficacy of four different types of muscle relaxants on the symptoms of the temporomandibular dysfunction [TMD] syndrome and to evaluate whether agents with antianxiety action provide better relief of symptoms. Method This randomized controlled single blind clinical trial was completed on 79 patients with the clinical diagnosis of myofascial pain. Patients were randomly divided into four groups. In each of the four groups, patients were given a different type of muscle relaxant three times a day for three weeks. A fifth group of control patients, who did not receive any medication, was later studied in a similar manner. Results A significant decrease in pain and mandibular dysfunction was found in all groups. Between-group analysis showed no differences in outcomes among five groups. Conclusions All four groups who received muscle relaxants exhibited reduced pain and improved function over the period of follow-up. Muscle relaxants with sedative effects were not found to be more efficient in relieving the symptoms than were non-sedating medications. With all four drugs, the reduction of pain continued with time of follow-up. Patients in the control group, who did not receive any medication showed a similar improvement.

Influence of coping strategies on oral health-related quality of life in patients with myalgia

Abstract Objective To identify coping strategies used by patients with myalgia and to assess the influence of pain characteristics and coping attitudes on their oral health-related quality of life (OHRQoL). Methods One hundred patients diagnosed with myalgia due to temporomandibular disorders were included in this study. They were administered a three-part questionnaire. For preselecting associated coping variables, correlation analysis was performed between coping strategies and OHRQoL domains. A block-wise hierarchical multiple regression analysis was carried out to evaluate whether coping strategies had any influence on OHRQoL. Results Notable trends were found between coping strategies and demographic variables and pain characteristics. OHRQoL appeared to worsen with pain severity and with coping strategies that reveal passive or avoidant attitudes of the patient. Discussion Individual coping strategies should be considered while managing myalgia. A multidisciplinary approach that aims to help these patients acquire suitable coping strategies may be useful in improving their OHRQoL.

Can an NTI-tss device be effective as a first-line therapy in patients with TMD myofascial pain?

This study was conducted to evaluate whether integrating a nociceptive trigeminal inhibition-tension suppression system (NTI-tss) device with first-line therapy of myofascial pain, which includes guidance, assurance, counselling and behavioural changes, would be more effective in alleviating symptoms. This randomised controlled clinical trial included 40 patients who were clinically diagnosed with myofascial pain according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Patients were randomly divided into two groups: the first group comprised patients who received guidance, assurance, counselling and behavioural changes; an NTI-tss device was integrated to this protocol in the second group. Both groups exhibited reduction in pain levels and improvement of jaw function compared with baseline values, but the difference was not significant. Both groups demonstrated improvements in 6 weeks; however, the integration of NTI-tss device into the therapy protocol did not provide any additional benefit in relieving symptoms of myofascial pain.