Comparison of Guided Bone Regeneration with Periosteal Pocket Flap Technique Versus Autogenous Bone Block Graft for Horizontal Bone Augmentation: A Clinical Trial Study

The aim of this study was to assess changes in the horizontal dimension of the alveolar ridge when the autogenous bone block (ABB) or periosteal pocket flap (PPF) techniques were performed prior to implant placement. This randomized trial study was conducted on 25 patients in need of horizontal bone augmentation, who were randomly divided into two groups as follows: 13 patients underwent ridge augmentation using ABB, allograft, and a collagen membrane, while the remaining 12 underwent horizontal bone augmentation via the PPF technique. For all patients, radiographic examinations via CBCT were performed both before and 26 weeks after the operation. Following the surgery, dimensional changes in the ridge width were measured both within and between the two groups in the three regions of 0, 3, and 5 mm from the top of the alveolar crest. A total of 11 patients in the ABB group and 12 patients in the PPF group successfully completed the study. Statistical analysis showed that the increase in alveolar ridge width in each group was significant, but not significantly different between the two groups at any of the measured spots (0 mm from the crest, P = .25; 3 mm, P = .38; and 5 mm, P = .73). However, more postoperative complications were observed with the ABB technique. According to the results of the present study, there was no statistically significant difference between the PPF and ABB techniques in terms of horizontal bone gain.

Crestal Sinus Floor Elevation with Autogenous Press-Fit Dowel Bone Harvested Using Trephine Drills: A New Method.

The aim of this study was clinical and radiographic evaluation of sinus floor lifting from the alveolar crest with trephine bur and autogenous bone graft. In this research, a press-fit dowel bone technique with application of an autogenous bone block was used for elevating the sinus floor. Ten closed sinus lift surgeries were performed on 10 patients; all patients possessed atrophic ridges in an edentulous maxilla. Bone height of the ridge ranged between 3 and 5 mm. Surgery included forming a bony cylinder with a trephine bur to reach the sinus cortical floor and then elevating the sinus floor bone with anosteotom and placing an autogenous bone block at the site and fitting it with strikes of a hand mallet. The amount of an osteotom sinus floor height gain was measured during implant placement and via radiography before surgery and four months postsurgery. Average height of the sinus floor bone after surgery was 8.33 mm with SD = 1.39 mm. Mean bone height gain after surgery in evaluated patients was 3.47 mm with SD = 1.4 mm. As a result, bone sinus floor height following surgery was significantly increased (P value = 0.044), with a significant difference between sinus floor bone height before and after surgery (P value = 0.041). No significant difference was observed between sinus floor bone height gain and sex, age, and smoking before and after the operation. The sinus floor lift method by trephine and autogenous bone graft is a practical and simple way to reduce the time needed for implantation in patients with moderate atrophy of the posterior maxilla.

Evaluation of crestal bone resorption around cylindrical and conical implants following 6 months of loading: A randomized clinical trial.

OBJECTIVE: The purpose of this clinical study was to evaluate the effect of implant body form (cylindrical and conical implants) on crestal bone levels during 6 months' follow-up after loading. MATERIALS AND METHODS: A total of 32 SPI implants (19 conical implants/13 cylindrical implants) were randomly placed in 12 male patients using a submerged approach. None of the patients had compromising medical conditions or parafunctional habits. Periapical radiographs using the parallel technique were taken after clinical loading and 6 months later. Clinical indices including pocket depth and bleeding on probing (BOP) were recorded on 6-month follow-up. Data were analyzed by independent samples t-test and Chi-square test with a significance level of 0.05. RESULTS: Six months after loading, crestal bone loss was 0.84 (±0.29) mm around the cylindrical implants and 0.73 (±0.62) mm around the conical types, which was not significantly different (P = 0.54). Pocket depth around the cylindrical and conical implants was 2.61 (±0.45) mm and 2.36 (±0.44) mm, respectively (P = 0.13). BOP was observed among 53.8% and 47.4% of the cylindrical implants and conical (P = 0.13). Bone loss and pocket depth in the maxilla and mandible had no significant difference (P = 0.46 and P = 0.09, respectively). CONCLUSION: In this study, although bone loss and clinical parameters were slightly higher in the cylindrical implants, there was no significant difference between the conical- and cylindrical-shaped implants.

The Effects of Smoking on Expression of IL-12 and IL-1ß in Gingival Tissues of Patients with Chronic Periodontitis.

AIM: The purpose of this study was to compare IL-1ß and IL-12 gene expression in the gingival tissue of smokers and non-smokers either with healthy periodontium or with chronic periodontitis. MATERIALS AND METHODS: 41 individuals consisting of 21 healthy controls (11 non-smokers and 10 smokers) and 20 chronic periodontitis patients (10 non-smokers and 10 smokers) participated in this study. Samples were collected from papillary regions of targeted areas and cytokines were analyzed using Real Time PCR. Shapiro-Wilk, Mann-Witney and Independent T tests were employed for statistical analysis. RESULTS: IL-1ß gene expression in gingival tissue of non-smoker group with chronic periodontitis was significantly higher than non-smoker-healthy group (p=0.011). Smoker-chronic periodontitis group showed lower IL-1ß gene expression than non-smoker-chronic periodontitis group (p=0.003). IL-12 gene expression was not significantly different between analyzed groups. CONCLUSION: IL-1ß gene expression increases in gingival tissue of non-smoker-chronic periodontitis patients due to inflammatory processes but smoking reduces the expression of this cytokine in diseased periodontal tissues. On the other hand periodontal condition and smoking habits do not seem to affect IL-12 gene expressions in gingival tissues. Authors concluded that reduced levels of IL1 and in some extent IL12 in smoking patients are responsible for higher tissue and bone degenerations and less treatment responses in smokers.

Clinical and Radiographic Evaluation of Demineralized Freeze-Dried Cancellous Block Allograft for Ridge Augmentation: A Pilot Study.

Bone resorption after tooth extraction is a common problem in implant dentistry. Allografts are one of the therapeutic techniques used to reconstruct the deficient ridge. Although this technique eliminates the need for a surgical donor site, it has yielded contradictory results. The aim of the present pilot study was to evaluate the clinical and radiographic results of the use of demineralized freeze-dried cancellous block allografts (DFDCBAs) in lateral ridge augmentation. Seven patients were included in this study. Lateral reconstruction of bone was performed using DFDCBA with stabilizing screws and resorbable collagen membranes. The ridge width was initially measured during the augmentation surgery. A second measurement was taken 6 months later at the time of implant placement. In addition, cone bean computed tomography images were used at both baseline and at 6-month reentry for measuring the width of bone by applying an acrylic stent with a radiopaque marker at the edentulous area. Paired t test was used to evaluate the statistical differences. The mean increase in the clinical and radiographic ridge widths were 1.70 ± 1.90 and 1.28 ± 1.52 mm, respectively, which were not statistically significant (P = 0.56 and P = 0.067, respectively). The results showed that the use of DFDCBAs in conjunction with resorbable membrane does not yield predictable results in the reconstruction of ridge width deficiencies.

Gene polymorphisms of TNF-α and IL-1ß are not associated with generalized aggressive periodontitis in an Iranian subpopulation.

Cytokines play a part in pathogenesis of periodontitis via inflammation phenomenon. Aggressive periodontitis (AgP) is a multifactorial disease resulting in rapid tooth loss due to severe destruction of tooth supporting apparatus. Recently, researchers have focused on genetic susceptibility of periodontitis through investigating the gene variations of cytokines and other components of immune response. In this study we analyzed single nucleotide polymorphism (SNP) of two cytokines in association with AgP in an Iranian-khorasanian population; Interleukin-1 beta (IL-1ß) +3954 C/T and Tumor Necrosis Factor alpha (TNF-α) -308 G/A. From arm vein of patients (n=58) and periodontally healthy individuals (n=60) blood sample was obtained and the DNA was extracted. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) procedure was performed to recognize the SNPs. X2 test was used to determine the statistically significant differences between the two groups. The frequency of genotypes and alleles had no significant differences between patients and control groups. The distributions were as follows. IL-1ß +3954: CT, CC and TT genotypes in patients were 39.6%, 60.4% and 0.0% and in controls were 41.7%, 50% and 8.3%, respectively. TNF-α -308: GA, GG and AA genotypes in patients were 44.8%, 41.4% and 13.8% and in controls were 46.7%, 50% and 3.3%, respectively.This investigation do not substantiates the role of IL-1ß +3954 and TNF-α -308 polymorphisms, separately, as risk determinants for AgP in Iranian population. Further research based on all components of immune response, is needed to corroborate the genetic susceptibility of AgP.

Evaluation of 3- to 8-year treatment outcomes and success rates with 6 implant brands in partially edentulous patients.

The use of osseointegrated implants as a foundation for the prosthetic replacement of missing teeth has become widespread, with new dental implant systems being introduced every year. There is growing interest in identifying the factors associated with implant failure, such as implant type. This study was designed to establish the relationship between implant type and success. Eighty-eight patients (mean age, 52 years) with 268 implants (110 BioHorizons, 60 ITI, 60 Paragon, 18 Xive, six 3i, and 19 Allfit) participated in this 5-year retrospective study. Statistical significance was defined for P < .05. Peri-implant probing depth was associated with bone loss and bleeding on probing. Implant failure was not associated with implant brand. Maximal (or minimal) peri-implant probing depth and bone loss values were seen at anterior regions (or premolars). Maximal (or minimal) bleeding on probing was seen at the posterior (or anterior) region. No significant differences were observed between the different systems in terms of implant failure.

Polymorphism of IL-1alpha(-889) Gene and Its Association with Aggressive Periodontitis.

Adult periodontitis is a complex multifactorial disease whose etiology is not well defined. The pro-inflammatory and bone resorption properties of Interleukine-1alpha (IL-1alpha) strongly suggest a role for this cytokine in the pathogenesis of periodontal disease. Eighty Iranian adult patients with periodontitis and 80 Iranian controls were investigated in this study.In this study we report that the frequency of IL-1alpha genotypes including allele 2 of the IL-1alpha(-889) restriction fragment length bi-allele polymorphism were significantly increased in patients with advanced aggressive adult periodontitis compared to those with early and moderate disease. Furthermore, allele 2 was associated with increased production of IL-1alpha by activated peripheral blood polymorphonuclear cells of patients with advanced disease, although this increase failed to reach statistical significance. Finally, the data obtained revealed significant linkage disequilibrium between allele 2 of the IL-1alpha (-889) polymorphism and allele 2 of the bi-allelic IL-1beta (+3953) polymorphism in both patients and orally normal controls. These findings provide new insight into the possible rate of IL-1alpha and beta genes polymorphism in the susceptibility to adult periodontitis.

The effect of periodontal treatment on IL-6 production of peripheral blood monocytes in aggressive periodontitis and chronic periodontitis patients.

BACKGROUND: Several cytokines, including IL-6 have been implicated in the pathogenesis of periodontal disease. It is established that monocytes from periodontitis subjects show an increased production of IL-6 as compared to healthy subjects. However, little is known about the effect of periodontal treatment on IL-6 production by monocytes in subsets of periodontitis patients. OBJECTIVE: The aim of the present study was to evaluate the effect of surgical periodontal treatment on IL-6 production of peripheral blood monocytes (PBM) in aggressive periodontitis patients (AP) and chronic periodontitis patients (CP) before and after stimulation by E.coli LPS. METHODS: Fifteen AP patients, 15 CP patients and 15 periodontally healthy subjects (PH) took part in the study. PBM IL-6 pro-duction was measured, using ELISA, before and after stimulation of cultured PBM cells by 0.1 microg/ml LPS of E.coli. Following full-mouth non-surgical and surgical periodontal treatment of the AP and CP groups, the same measurements were repeated for these two groups. RESULTS: LPS-stimulated IL-6 production was significantly greater than non-stimulated IL-6 for all 3 groups. Before periodontal treatment, LPS-stimulated IL-6 pro-duction of the AP group was significantly greater than the other 2 groups. Periodontal treatment did not result in a significant decrease in unstimulated or LPS-stimulated IL-6 production by PBM cells in AP and CP patients. No correlation was detected between IL-6 levels and baseline clinical parameters or changes in clinical parameters. CONCLUSION: PBM cells in AP patients might be hyper-responsive in terms of IL-6 production. This hyper-responsiveness does not seem to return to that of healthy subjects even after a successful periodontal treatment. Moreover, the regulation of host inflammatory mechanisms upon LPS challenge might be different between AP and CP patients.