This study aimed to investigate the effects of chronic restraint stress (RS) and a high-fat diet (HFD) on the osseointegration of titanium implants in a rat model. After the surgical insertion of titanium implants into the metaphysis of the tibial bone, the rats were randomly divided into four equal groups (n = 8 each): control (CNT), restraint stress (RS), high-fat diet (HFD), and restraint stress plus high fat diet (RS-HFD). CNT: Rats received no further treatment during the 92-day experimental period. RS: Stress was applied to the rats beginning from two days after the implant surgery for one hour per day for the first 30 days, two hours per day for the next 30 days, and three hours per day for the last 30 days. HFD: Rats were fed a HFD for the following 90 days starting two days after surgery. RS-HFD: Rats were fed a HFD and RS was applied to rats for the following 90 days, starting two days after surgery. At the end of the experimental period, the rats were euthanized, and the implants and surrounding bone tissues were removed for histological analysis. Statistical analysis was performed by one way ANOVA and Bonferrroni tests. There were no significant differences in the bone-implant connection levels between the groups (p > 0.05), but in the HFD and RS-HFD groups, the bone filling ratios were found to be lower compared with the controls (p < 0.05) The data analyzed in this study suggest that an HFD with or without chronic RS adversely affected bone tissue in the rats during the 90-day osseointegration period.

The aim of the present study was to investigate the reasons for the persistence of primary teeth and also use panoramic radiography to determine the characteristics of persistence teeth. Four-hundred and twenty-six panoramic radiographies, which diagnosed one or more retained primary teeth, were selected from 100,577 panoramic radiographic image files from nine clinics and six different cities in Turkey. The selected radiographies were evaluated to determine the reasons for the persistence of primary teeth; furthermore, this study analyzed the characteristics of the retained primary teeth including tooth type, number, location, and root resorption, and whether, or not, the primary teeth showed evidence of pathological conditions, such as periodontal problems, caries, ankylosis, infra-occlusions, or tipping of the adjacent permanent teeth. Six hundred and seventy-seven retained primary teeth were determined in 426 patients (148 males and 278 females). Retained primary teeth were found most frequently in the mandible rather than the maxilla and the left side was more frequently affected than the right side. Level 1 was found as a most frequently encountered root resorption level. Within the limitation of the present study, the most common type of persistent primary teeth seen on the dental arch were mandibular primary second molars, followed by maxillary primary canines. The most frequent reason for the persistence was the congenital absence of successors to the primary teeth, followed by impaction of the successor teeth.

The aim of this study was to evaluate the effects of local and systemic zoledronic acid (ZA) applications on titaniumoksit ceramic blasted (TiO-CB)- and sandblasted large acid-grit (SLA)-surfaced titanium implant osseointegration. Twelve New Zealand White rabbits were used in the study, divided into 6 groups: the TiO-CB (TiO-CB-CNT) (n = 2) and SLA (SLA-CNT) (n = 2) control groups in which TiO-CB- and SLA-surfaced titanium implants were surgically inserted into rabbit tibias but no treatment was applied; the TiO-CB (TiO-CB-LZA) (n = 2) and SLA (SLA-LZA) (n = 2) local ZA groups in which 1 mL of normal saline solution containing 2 mg of ZA was injected into sockets and after this the implants were integrated; and the TiO-CB (TiO-CB-SZA) (n = 2) and SLA (SLA-SZA) (n = 2) systemic ZA groups in which a single infusion of 0.1 mg/kg of ZA was administered during surgical implant insertion. Following a period of osseointegration, bone implant contact (BIC) was recorded as a proportion of the total implant surface length in direct contact with the bone. Results of this study indicate that BIC was greater in the systemic ZA application groups than in the local ZA application groups, and BIC was greater in the local ZA groups than in the controls. Statistically significant differences in BIC were not detected between the TiO-CB- and SLA-surfaced implants in all the groups. Furthermore, this study did not reveal significant differences between the 2 types of surfaces due to similar average roughness values. Overall, systemic ZA application was found to be more effective in increasing BIC than local ZA application based on the results obtained by testing 2 implant surfaces.

The aim of this study was to compare the effects of hydroxyapatite (HA), deproteinized bovine bone (DPB), human-derived allogenic bone (HALG), and calcium sulfate (CAP) graft biomaterials used with titanium barriers for bone augmentation to treat peri-implant defects in rat calvarium treated by guided bone regeneration (GBR). Thirty-two female Sprague-Dawley rats were divided into four groups: DPB, HALG, HA, and CAP. One titanium barrier was fixed to each rat's calvarium after the titanium implants had been fixed. In total, 32 titanium implants and barriers were used. Ninety days after the surgical procedure, all the barriers were removed. After decalcification of bone tissue, the titanium implants were removed gently, and new bone regeneration in the peri-implant area was analyzed histologically. Immunohistochemical staining of vascular endothelial growth factor (VEGF) was also performed. There were no statistically significant between-group differences in new bone regeneration or VEGF expression after 3 months. According to the results of the histological and immunohistochemical analyses, none of the grafts used in this study showed superiority with respect to new bone formation.

Tissue engineering arouses excitement in all medical fields that deal with bone healing. The ultimate aim of these approaches are to shorten the healing process, obtain highly differentiated functional tissues and eliminate the need for a second surgical site required for autogenous bone grafts. Mesenchymal stem cells have been increasingly used in the experiments which were conducted in these fields and the results are promising. Dental stem cells have come to the forefront both because of their relative ease of access and also their superior characteristics. This article investigates the importance of dental stem cells for bone tissue engineering and their regeneration potentials.