MATERIALS AND METHODS: Twenty-one patients with implants were included in this study and implants were assessed by resonance frequency analysis (RFA). Bone levels of the implants were assessed by measuring mesial and distal bone levels from the periapical radiograph, and soft tissue was assessed from probing depth using a periodontal probe. Implants were assessed for stability and probing depth at pre-loading, at 3 months and 6 months post-loading. RFA and probing depth were statistically compared from different time points. Correlation of probing depth and marginal bone loss with implant stability was also determined.
RESULTS: The average change in implant stability quotient (ISQ) measurements from pre-loading to 6 months post-loading was found to be statistically significant (p <0.005). The average probing depth reduced from 1.767 mm at pre-loading to 1.671 mm at post-loading 3 months, and 1.600 mm at post-loading 6 months. At 6 months of function, radiographic examination yielded 0.786 mm mesial bone loss and 0.8 mm distal bone loss. It was found to be statistically significant (p <0.005) but within an acceptable range. No significant correlation was found between implant stability and bone loss; and implant stability and probing depth.
CONCLUSION: The study revealed an increasing trend in implant stability values with the time that indicates successful osseointegration. Increasing mean values for mesial and distal bone loss were also found.
CLINICAL SIGNIFICANCE: The success of dental implants is highly dependent on the quality of bone and implant-bone interface, i.e., osseointegration. The most important factors that influence the survival rate of an implant is initial stability. The present study found the changes in the peri-implant hard and soft tissues and implant stability. This article, while being a prospective study, may show the evidence of successful osseointegration by increasing trend in implant stability (RFA) values with time which can help to the clinician in the long-term management of implants.
METHODOLOGY: Five electronic databases were searched for studies that compared implant outcomes in patients with differing HbA1c values. Research quality was evaluated using Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) tool. Narrative synthesis and meta-analysis were performed for survival rate, plaque index (PI), bleeding on probing (BOP), probing pocket depth, and marginal bone loss (MBL). Categorical dose-response meta-analysis (DRMA) was conducted according to length of follow-up.
RESULTS: Twenty-two studies met the inclusion criteria. Prospective studies were mostly of moderate quality, but non-prospective papers had serious to critical risk of bias. Survival rate was high for the first 3 years (92.6%-100%) for patients with HbA1c less than 8%. Meta-analysis revealed worsening clinical parameters with increasing HbA1c. DRMA further established a significant dose-response relationship between glycemic control with BOP (10% more bleeding, 95% CI 0.05-0.16, P = .008) and MBL (0.05 mm more bone loss, 95% CI 0.01-0.09, P = .002) per HbA1c category, but no association with probing pocket depth. Osseointegration progressed at a slower rate, and inflammatory cytokines and bone biomarkers were adversely affected in patients with HbA1c above 8%.
CONCLUSION: Moderate evidence suggests a high short-term survival but possible dose-response trend of worsening BOP and MBL in association with glycemic control. Clinically, HbA1c values must be considered for risk assessment before placement and throughout the lifespan of the implant placed in a patient with diabetes.
MATERIALS AND METHODS: The test group included 9 participants rehabilitated by maxillary CD opposing mandibular IRO, while the control group consisted of 4 participants with CDs. Blood flow was measured by laser Doppler flowmetry (LDF) after denture removal for 0, 30, 60, and 90 minutes. RRR was quantified as reduction in bone volume a year post-treatment. The measurement of blood flow was then compared to the quantification of RRR.
RESULTS: The mean blood flow measure for the IRO group was significantly lower than CD after immediate denture removal and 30 minutes later. After 60 minutes, the mean difference was not significant between groups, and at 90 minutes, the mean blood flow of both groups equalized to reach a steady state of 377 BPU. The mandibular IRO had reduced the initial blood flow measure in the opposing anterior maxilla mucosa to almost a quarter (103 BPU) of the steady state value (377 BPU) compared to the CD, which reduced it to only about one half (183 BPU), suggesting greater blood flow disturbance in the IRO group. This result is in tandem with the greater reduction of bone volume observed in the IRO group, which was 7.3 ± 1.3% after a year, almost three times higher than CD group at 2.6 ± 1.7%.
CONCLUSION: IRO may cause significantly higher blood flow disturbance than CD and may have contributed to greater RRR in the anterior maxilla.
PURPOSE: The purpose of this systematic review was to evaluate crestal bone loss (CBL) around zirconia dental implants and clinical periimplant inflammatory parameters.
MATERIAL AND METHODS: The focus question addressed was, "Do zirconia implants maintain crestal bone levels and periimplant soft tissue health?" Databases were searched for articles from 1977 through September 2014 with different combinations of the following MeSH terms: "dental implants," "zirconium," "alveolar bone loss," "periodontal attachment loss," "periodontal pocket," "periodontal index." Letters to the editor, case reports, commentaries, review articles, and articles published in languages other than English were excluded.
RESULTS: Thirteen clinical studies were included. In 8 of the studies, the CBL around zirconia implants was comparable between baseline and follow-up. In the other 5 studies, the CBL around zirconia implants was significantly higher at follow-up. Among the studies that used titanium implants as controls, 2 studies showed significantly higher CBL around zirconia implants, and in 1 study, the CBL around zirconia and titanium implants was comparable. The reported implant survival rates for zirconia implants ranged between 67.6% and 100%. Eleven studies selectively reported the periimplant inflammatory parameters.
CONCLUSIONS: Because of the variations in study design and methodology, it was difficult to reach a consensus regarding the efficacy of zirconia implants in maintaining crestal bone levels and periimplant soft tissue health.
MATERIALS AND METHODS: Three-dimensional solid models of the maxilla, mucosa, and denture of a selected edentulous patient were created using Mimics and CATIA software. The FEA model was created and duplicated in ANSYS 16.0 to perform two simulations for the IOD and the CD models. The values of maximum stress and strain and total deformation were obtained and compared to the outcomes of premaxilla resorption from a parallel clinical study.
RESULTS: The maximum principal stress in the premaxilla in the IOD model ranged from 0.019 to 0.336 MPa, while it ranged from 0.011 to 0.193 MPa in the CD model. The maximum principal strain in the IOD model was 1.75 times greater than that in the CD model. Total deformation was 1.8 times higher in the IOD model. Greater bone resorption was observed in regions of higher stress, which were on the occlusal and buccal sides of the premaxilla residual ridge.
CONCLUSION: Stress, strain, and total deformation values present in the premaxilla area beneath a CD were approximately two times greater in a comparison between an opposing mandibular two-IOD and an opposing mandibular CD. The results were consistent with a parallel clinical study in which the rate of premaxilla bone resorption was almost three times greater in the IOD group.
MATERIALS AND METHODS: 18 patients were rehabilitated with maxillary CD opposing mandibular IRO, and 4 patients were prescribed with conventional CD. Cone beam computed tomography (CBCT) scans of the maxilla were acquired before and 1 year post-treatment and converted into 3D models using Mimics research software. RRR was quantified by measuring the changes in bone volume following superimpositioning and sectioning of these models at the anterior maxillary region. Subsequently, the sectioned 3D models of the anterior maxilla were exported to 3-Matic software to reveal the predominant region and depth of RRR.
RESULTS: The mean reduction in bone volume of the anterior maxilla in the CD group was 2.60% (SD = 1.71%, range = -4.89 % to -0.92%, median = -2.30%), while the mean reduction in the IRO group was almost three times higher at 7.25% (SD = 3.16%, range = -13.25 to -1.50, median = -7.15%). The predominant areas of RRR were on the buccal and occlusal ridge of the anterior maxilla.
CONCLUSION: Within the limits of this study, it may be concluded that an IRO caused significantly higher RRR of the anterior maxilla than a CD.
OBJECTIVE: The aim of this study is to evaluate the effectiveness of bovine bone granules on alveolar bone socket augmentation for ridge preservation following atraumatic tooth extraction.
MATERIALS AND METHODS: Twenty medically fit patients (12 males and 8 females aged between 18 and 40 years) who needed noncomplicated tooth extraction of 1 mandibular premolar tooth were divided randomly and equally into 2 groups. In control group I, the empty extraction socket was left untreated and allowed to heal in a conventional way. In group II, the empty extraction socket wound was filled with lyophilized bovine bone xenograft granules 0.25 to 1 mm of size, 1 mL/vial. A resorbable pericardium membrane was placed to cover the defect. Clinical and 3-dimensional radiological assessments were performed at day 0, 3 months, and 9 months postoperative.
RESULTS: There were no clinical differences in general wound healing between the groups. Comparisons within the groups showed a significant difference of bone resorption of 1.49 mm (95% confidence interval, 0.63-2.35) at 3 months, and further resorption of 1.84 mm (P ≤ 0.05) at 9 months in the control group. No significant changes of bone resorption were observed in group II during the same time interval. Comparison between groups showed a significant difference of bone resorption at 3 and 9 months (2.40 and 2.88 mm, respectively).
CONCLUSION: The use of lyophilized demineralized bovine bone granules in socket preservation to fill in the extraction socket seems essential in preserving the alveolar bone dimension as it showed excellent soft and hard tissue healing. This study concludes that the alveolar bone socket exhibited a dynamic process of resorption from the first day of tooth extraction. Evidence shows the possibility of using bovine bone granules routinely in socket volume preservation techniques following tooth extraction.