Using Platelet-Rich Fibrin in Combination With Allograft Bone Particles Can Induce Bone Formation in Maxillary Sinus Augmentation.

BACKGROUND: Sinus pneumatization secondary to posterior maxillary tooth extraction can hinder proper implant installation. Maxillary sinus floor augmentation is a surgical procedure that has been proposed to overcome this issue. PURPOSE: The aim of this study was to evaluate and compare the histomorphometric outcomes of sinus floor elevation using allograft bone particles with or without platelet-rich fibrin (PRF). STUDY DESIGN, SETTING, SAMPLE: This randomized clinical trial included patients scheduled for maxillary sinus floor elevation in the Implant Department of Mashhad Dental School. Healthy adults with an edentulous maxilla and residual alveolar bone height of 3 mm or less were eligible to participate and were randomly allocated to intervention (A) or control (B) groups. Bone biopsies were obtained 6 months postoperatively. PREDICTOR VARIABLE: The predictor variable was using a PRF membrane for maxillary sinus augmentation. In group A, sinus floor elevation was performed using PRF combined with bone allografts, while in group B only allograft particles were used. MAIN OUTCOME VARIABLES: The primary outcome variables were the recorded postoperative histologic parameters, as in the area of newly formed bone, new bone marrow, and residual graft particles (µm2). The secondary outcome variables were the radiographically measured postoperative bone height and width at the graft site. COVARIATES: Age and sex. ANALYSES: Independent sample t-test was employed to compare the postoperative histomorphometric parameters between groups A and B. P value ≤ .05 was considered statistically significant. RESULTS: A total of 20 patients (10 per group) completed the study. The mean rate of new bone formation was 43.25 ± 5.22% in group A and 38.25 ± 7.01% in group B. This difference was statistically insignificant (P = .087). The mean amount of newly formed bone marrow was significantly more in group A compared to group B (6.81 ± 2.19% vs 10.23 ± 4.49%; P = .044). The average amount of remaining particles was also significantly less in group A patients (9.35 ± 3.43% vs 13.18 ± 3.67%; P = .027). CONCLUSION AND RELEVANCE: Incorporating PRF as an adjunctive grafting material results in fewer residual particles of allograft and in more bone marrow formation and may serve as a treatment option for developing the atrophic posterior maxilla.

Tapered Versus Cylindrical Implant: Which Shape Inflicts Less Pain After Dental Implant Surgery? A Clinical Trial.

PURPOSE: Because no study has evaluated the postoperative pain caused by the shape of dental implants, this study compared the level of postoperative pain between tapered and cylindrical implants inserted in the posterior region of the maxilla. MATERIALS AND METHODS: The study was designed as a double-blinded randomized clinical trial and conducted in 50 healthy patients 20 to 60 years old who were edentulous in the posterior maxilla and were candidates for single implantation. All patients had the same surgical difficulty with appropriate bone width and height. BioHorizons (Birmingham, AL) implants (tapered vs cylindrical) with 4.5-mm platform diameter were randomly selected for each group. The visual analog scale was used to evaluate the level of pain. Pain severity in each group was measured at 30-minute, 3-hour, 6-hour, 12-hour, 24-hour, 2-day, 3-day, and 1-week intervals. The predictor variable was implant shape and the outcome was postoperative pain severity. Data were statistically analyzed with SPPS 16 (SPSS, Inc, Chicago, IL) at the significance level of a P value less than .05. RESULTS: Fifty patients (n = 25 per group) with the mean age of 43.7 ± 10.9 years were included in this study. The pain level in the 2 groups reached its maximum at the 6-hour postoperative interval. Pain severity decreased significantly over time in the 2 implant groups (P < .001). Severities of postoperative pain in the tapered group at 3-, 6-, 12-, and 24-hour intervals were statistically lower than those in the cylindrical group (P < .05). CONCLUSIONS: Implant shape had an impact on postoperative pain. It can be concluded that tapered implants lead to less postoperative pain compared with cylindrical ones.

Effect of Acellular Dermal Matrix Placement Simultaneous with Implant Placement on Vertical Soft Tissue Thickness: A Randomized Controlled Clinical Trial.

Acellular dermal matrix (ADM) is commonly used for soft tissue augmentation in root coverage, increasing the width of keratinized gingiva or vestibular depth, or filling the localized alveolar bone defects. This parallel-design randomized controlled clinical trial assessed the effect of ADM membrane placement simultaneous with implant placement on vertical soft tissue thickness. A total of 25 submerged implants were placed in 25 patients (8 men, 17 women) with vertical soft tissue thickness < 3 mm at the surgical site. Patients were randomized into two groups: The intervention group (n = 13) received ADM over the implant for soft tissue augmentation, while no augmentation was performed for the control group (n = 12). After 3 months, healing abutments were placed, and the soft tissue thickness at the surgical site was measured again with a periodontal probe in both groups. Data were analyzed using Mann-Whitney and Wilcoxon tests. All 25 patients were successfully treated. The presurgical vertical soft tissue thickness was 2 mm and 1.92 mm in the control and test groups, respectively (P > .05). These values changed to 1.83 mm and 2.69 mm, respectively, after the intervention. The mean gain in soft tissue thickness was 0.76 mm in the test group, and the difference between groups was statistically significant (P < .05). ADM membrane can be successfully used to augment vertical soft tissue thickness simultaneous with implant placement.

Analyzing the Causes and Frequency of Early Dental Implant Failure among Iranians: An Epidemiological Study.

Aim: The rate of early dental implant failure (DIF) has increased in recent years, though the risk factors associated with this primary failure remain unclear. This study aimed to determine the rate of early implant failure and identify contributing factors. It was conducted from March 2018 to 2020 in Mashhad, Iran. Method: This observational study examined the records of 983 implants from the Implant Department of Mashhad Dental School. Variables considered included age, gender, systemic diseases, smoking habits, implant type and size, and surgery-related factors. Data were analyzed using Chi-square, Mann-Whitney U, and Fisher exact tests in SPSS V22, with a p-value of 0.05 or less considered statistically significant. Result: Of the 983 implants, 42 (4.3%) experienced early failure. The study population consisted of 555 (56.5%) females and 428 (43.5%) males, with an average age of 49.34 ± 13.67 years. A significant correlation was found between surgical complications (e.g., fracture of implant fixtures and inferior alveolar nerve exposure) and implant loading time (Yes or No) with early DIF (p=0.05 and p < 0.01, respectively). However, no significant correlation was observed between early failure and factors such as age, gender, smoking habits, systemic diseases, implant dimensions, or manufacturer. Conclusion: Surgical complications and loading time may be the most critical factors contributing to early implant failure. Therefore, we suggest dentists pay attention to the mentioned factors in the surgical protocols and their relationship. Further prospective studies on risk factors that could affect early implant failure are needed.

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.

Treatment of a Hopeless Tooth with Combined Endodontic-periodontal Lesion Using Guided Tissue Regeneration: A Case Report with One Year Follow-up.

Endodontic-periodontal lesions have always been a challenge for treatment due to the reduced success rate in comparison to endodontic or periodontal lesions alone. This case report describes surgical/endodontic management of supra-erupted non-vital maxillary incisor with primary periodontal and secondary endodontic lesions with mobility grade III and severe horizontal and vertical loss of attachment apparatus in a 55 years old woman with aggressive periodontitis. The successful results at one-year follow-up revealed that with an appropriate case selection strategy, proper regeneration method and soft tissue enhancement, severe combined endo-perio lesions may treat.

Correlation between gray values in cone-beam computed tomography and histomorphometric analysis.

Purpose: The aim of this study was to analyze the relationships between bone density measurements obtained using cone-beam computed tomography (CBCT) and morphometric parameters of bone determined by histomorphometric analysis. Materials and Methods: In this in vivo study, 30 samples from the maxillary bones of 7 sheep were acquired using a trephine. The bone samples were returned to their original sites, and the sheep heads were imaged using CBCT. On the CBCT images, gray values were calculated. In the histomorphometric analysis, the total bone volume, the trabecular bone volume (referred to simply as bone volume), and the trabecular thickness were assessed. Results: Statistical testing showed significant correlations between CBCT gray values and total bone volume (r=0.537, P=0.002), bone volume (r=0.672, P<0.001), and trabecular thickness (r=0.692, P<0.001), as determined via the histomorphometric analysis. Conclusion: The results indicate a significant and acceptable association between CBCT gray values and bone volume, suggesting that CBCT may be used in bone densitometry.

Clinical and Histological Evaluation of Tissue Healing in Beveled or Perpendicular Vertical Releasing Incision.

OBJECTIVES: The aim of this investigation was to evaluate the clinical and histological differences in wound healing between beveled and perpendicular vertical releasing incisions in dogs. MATERIAL AND METHODS: Four male mongrel dogs were used in this investigation. In each quadrant, a vertical releasing incision was made on either the mesial or the distal aspect of the cuspid teeth of each animal all on the same day. The sites were randomly selected to either receive a beveled incision or a perpendicular incision. A sulcular muco-periosteal flap was raised, reapproximated, and then sutured using 3-0 Vicryl. The animals were evaluated daily for the first week, and then at different time intervals during this investigation. One animal was killed at each time interval of 9, 14, 21, and 28 days after surgery. One animal was killed at each time interval, and a bone block consisting of the cuspid teeth and their surrounding bone and soft tissues was harvested, formalin fixed, and paraffin embedded. Samples were sectioned serially and stained with hematoxylin-eosin. Specimens were evaluated using a microscope with magnification ranging from ×10 to ×400 by a histopathologist. Four indices were used for histologic evaluation. RESULTS: At day 9 after surgery, a visible groove was seen in the marginal tissues of both perpendicular and beveled incisions. At day 9, both of the histologic sections showed less organized connective tissue and capillary networks with no significant difference in inflammation. In the 14-day samples, a depression was still present at the perpendicular incision sites, but not in the beveled incision group, where the groove was not visualized at all. In the 21- and 28-day samples, irregular capillary arrangements were seen in the connective tissue of the perpendicular incision groups with completely healed epithelium. There were no statistically significant differences noted histologically between the beveled and perpendicular incision groups noted at 9, 14, 21, or 28 days (P > .05). CONCLUSION: Based on these findings, it appears that clinical and histologic healing of beveled or perpendicular releasing incisions are similar 28 days after surgery.

Evaluating Vitality and Periodontal Sensitivity of Teeth Adjacent to the Site of Open Sinus Lift Surgery before and after Treatment: A Case Series Study.

The aim of this study was to evaluate the effect of open sinus lift surgery on dental vitality and periodontal sensitivity of teeth adjacent to a surgery area. Forty-one patients undergoing open sinus lift surgery were evaluated for dental vitality and periodontal sensitivity of adjacent teeth. Dental vitality was evaluated using an electric pulp tester and cold spray. Periodontal sensitivity of teeth in the surgery area of open sinus lift was evaluated by interview and visual analogue scale before surgery and one, three, and six weeks after surgery. In order to increase the validity of the study, one healthy tooth was considered as a control. In the experimental group, differences in periodontal sensitivity were significant between the four measured times (P < 0.001). Pretreatment compared with three weeks posttreatment, pretreatment compared with one week posttreatment, six weeks posttreatment compared with one week posttreatment, and three weeks posttreatment compared with one week posttreatment showed significant differences (P = 0.001). In the control group, the periodontal sensitivity between the four measured times did not differ significantly (P = 0.421). In the experimental group, pulpal sensitivity was significant between the four measured times (P = 0.019). It was found that the test and control groups showed significant differences in pretreatment versus six weeks posttreatment and one week posttreatment versus three weeks posttreatment (P < 0.001). Pulse sensitivity significantly changed after open sinus lift surgery, making it clear that the surgery may lead to necrosis of adjacent teeth. However, further research is needed. Also, teeth in area of the surgery may be periodontally affected, but will undergo recovery.

Is Impregnation of Xenograft with Caffeine Effective on Bone Healing Rate in Mandibular Defects? A Pilot Histological Animal Study.

INTRODUCTION AND AIM: The aim of this study was to evaluate the effect of two concentrations of caffeine (1.5% and 3%) powder added to Bio-Oss xenograft on bone healing rate of iatrogenic mandibular defects in dogs. MATERIALS AND METHOD: The researchers implemented a pilot study on ten male adult mongrel dogs. Two 4-mm circular critical-sized defects were trephined on each side of the mandibular body (a total of 4 defects for each dog). One of the defects remained empty as a control group. The other three defects in each case were randomly filled with 1.5% or 3% caffeinated Bio-Oss or pure Bio-Oss. The mandible specimens were sent for histological and histomorphometric assessments, 4 months postoperatively. Our predictor variable was the type of bone substitute. The study outcomes were new bone formation, angiogenesis, and fibrosis. The p value was set at 0.05 using SPSS 16. RESULTS: The histological assessment showed that the administration of 1.5% caffeinated Bio-Oss to mandibular defects caused more angiogenesis and more new bone formation as well as less fibrosis compared to the other groups (p < 0.05). CONCLUSION: This study suggested that the application of 1.5% caffeinated Bio-Oss in bone defects of dogs resulted in the higher new bone formation. However, further clinical trials are needed to support its relevancy.