Effect of methylphenidate at different doses on new bone formation with rapid maxillary expansion: A micro-CT and histomorphometric study in rats.

OBJECTIVES: This study aimed to evaluate the effect of systemically administered methylphenidate hydrochloride (MPH) on new bone formation in premaxillary suture after rapid maxillary expansion (RME). SETTING AND SAMPLE POPULATION: Thirty-three Wistar rats were divided into four groups: Group 1 (high dose, 30/60 mg/kg MPH), Group 2 (low dose, 4/10 mg/kg MPH), Group 3 (positive control) and Group 4 (negative control). METHODS: RME was applied on the 70th day of the study. A 5-day RME period was followed by a 12-day retention period. The experiment was terminated on the 87th day. Micro-CT for radiological evaluation, haematoxylin-eosin and Masson's trichrome staining methods were used for histomorphometric evaluation. RESULTS: Among experimental groups with RME, the lowest number of osteoblasts and capillaries in Group 1 (P < .05). New bone formation, fibrous callus formation, distal osteotomy line, proximal osteotomy union and cortex remodelling were observed to be lower in Group 1 and Group 2 than Group 3 (P < .05). There was a statistically significant difference between Group 4 and each of the other groups (P = .000) in the evaluation of the results for bone mineral density, bone volume, bone volume percentage, trabecular thickness and trabecular number. CONCLUSIONS: MPH reduces cellular activity for new bone formation in suture in RME groups. Before performing rapid maxillary expansion in patients using MPH, the use of the drug should be postponed after a multidisciplinary decision process or clinical doses should be lowered.

Effect of hyaluronic acid on the osseointegration of dental implants.

The mechanism of osseointegration is related to many factors, including the quality of the bone, the biocompatibility and surface characteristics of the implant material, the surgical technique, and functional loading. The purpose of this study was to investigate the effects of hyaluronic acid gel on the osseointegration of implants placed in defined areas of the mandible in rabbits. Hyaluronic acid is known to have an osteoinductive effect during regeneration of bony defects, and we thought that it might also have a favourable effect on osseointegration, a specialised mechanism to heal bone. Ten New Zealand rabbits aged 10 weeks and weighing 2.5-3.0kg were used, and sites for implants that were far enough from the apices of the teeth in the mandibular molar area were chosen. Two cavities were prepared in each rabbit, one (anterior) for the control implant, and one (posterior) for the implant with hyaluronic acid gel (Medical Instinct GmbH, Bovenden). New bone and the osteoid matrix content around the dental implants were evaluated histologically and histomorphometrically two months after the operation, and no significant difference was found between the two groups.

New inflammatory markers in early rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is the most common chronic inflammatory disorder and is associated with progressive destruction of synovial joints and physical disability. Therapies with known benefits include disease-modifying antirheumatic drugs (DMARDs), such as methotrexate, as well as more recent biologic agents, such as tumor necrosis factor inhibitors (anti-TNF therapy). METHOD: This was a retrospective study, which included 205 RA and 112 early RA (ERA) patients from the Rheumatology Clinic at Gaziantep University School of Medicine Research Center as well as 104 healthy controls. RESULTS: The mean neutrophil to lymphocyte ratio (NLR) was found to be 3.15 ± 2.64 in the patient group and 2.03 ± 0.94 in the control group. The mean platelet to lymphocyte ratio (PLR) was 162.39 ± 107.76 in the patient group and 131.23 ± 48.09 in the control group. There was a significant difference in both the NLR and PLR between the patient and control groups (both p < 0.01). There was a significant difference in both the NLR and PLR between patients with active disease and remission (both p < 0.001) in RA, including anti-TNF therapy and DMARDs groups. There was a significant difference in NLR (p = 0.001) but not in PLR (p = 0.051) between active disease and remission in ERA. CONCLUSION: The results of the present study suggest that the NLR may be considered a useful marker of disease activity in RA and one that can aid the diagnosis of ERA. The PLR can be used in the assessment of disease activity in RA patients undergoing anti-TNF therapy but is not suitable for diagnosing ERA.

Systemic vasculitis in a patient with rhupus syndrome.

Rhupus is a rare syndrome characterized by overlap of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Previous reports mentioned that rhupus patients have prominent RA associated clinical manifestations and only mild organic damage related to SLE. Progressive or life-threatening manifestations are rare in rhupus patients. Our patient diagnosed as rhupus was a young women, presented with multi-organ involvement of systemic vasculitis. Rheumatologists should be aware of possibility that rhupus may be accompanied by progressive or life-threatening conditions such as vasculitis.