ABSTRACT
PURPOSE: : The aim of this retrospective clinical trial was to evaluate the survival rates and the marginal bone levels of immediately placed implants in fresh extraction sockets in a period of 36 months. PATIENTS AND METHODS: : One hundred seventeen patients who had received 165 immediately placed implants and followed up for 36 months after loading were included in this retrospective study. Survival rate and mesial and distal marginal bone levels of all implants were determined with the measurements made on periapical radiographs at baseline and recall evaluations. RESULTS: : The results of clinical evaluation showed a survival rate of 93.94%. Ten of 165 implants failed: 7 implants in female patients indicating 90.28% survival rate and 3 male patients with 93.4% survival rate. The mean age of patients with implant failure was 60.8 years. No statistically significant differences in marginal bone levels with respect to localization, age, gender, grafting, and implant brands were noted. Grafting did not influence plaque index, gingival index, and periimplant probing depth in a statistically significant way. CONCLUSIONS: : The results suggest that immediately placed single implants show acceptable survival rates and mesial and distal marginal bone levels in 36-month follow-up period.
Subject(s)
Dental Implants, Single-Tooth , Immediate Dental Implant Loading , Adolescent , Adult , Aged , Alveolar Bone Loss/classification , Alveolar Bone Loss/diagnostic imaging , Alveolar Process/diagnostic imaging , Bone Substitutes/therapeutic use , Crowns , Dental Implants, Single-Tooth/classification , Dental Plaque Index , Dental Prosthesis, Implant-Supported , Dental Restoration Failure , Female , Follow-Up Studies , Humans , Male , Membranes, Artificial , Middle Aged , Periodontal Index , Radiography, Bitewing , Retrospective Studies , Single-Blind Method , Survival Analysis , Tooth Extraction , Tooth Socket/diagnostic imaging , Treatment Outcome , Young AdultABSTRACT
PURPOSE: Critical bending moment (CBM), defined as the bending moment at which the external nonaxial load applied overcomes screw joint preload and causes loss of contact between the mating surfaces of the implant screw joint components, was measured for four different implants and their single-tooth replacement abutments. MATERIALS AND METHODS: CBM at the implant-abutment screw joint for four implant-abutment test groups was measured in vitro at 80%, 100%, and 120% of the manufacturers' recommended torque levels. Regular-platform implants with their corresponding single-tooth abutments were used. Microstrain was measured while known loads were applied to the abutment at known distances from the implant-abutment interface. Strain instrumentation was used to record the strain data dynamically to determine the point of gap opening. All torque applications and strain measurements were repeated five times for the five samples in each group. RESULTS: For the Branemark/CeraOne assemblies, the mean CBMs were 72.14 Ncm, 102.21 Ncm, and 119.13 Ncm, respectively, at 80%, 100%, and 120% of the manufacturer's recommended torque. For the Replace/Easy assemblies, mean CBMs were 86.20 Ncm, 109.92 Ncm, and 120.93 Ncm; for the Biomet 3i/STA assemblies, they were 67.97 Ncm, 83.14 Ncm, and 91.81 Ncm; and for the Lifecore/COC assemblies, they were 58.32 Ncm, 76.79 Ncm, and 78.93 Ncm. Two-way analysis of variance revealed significant effects for the test groups and torque levels. Subsequent tests confirmed that significant differences existed between test groups and torque levels. CONCLUSION: The results appear to confirm the primary role of the compressive preload imparted by the abutment screw in maintaining screw joint integrity. CBM was found to differ among implant systems and torque levels. Torque levels recommended by the manufacturer should be followed to ensure screw joint integrity.
Subject(s)
Dental Abutments , Dental Implants, Single-Tooth , Dental Prosthesis Design , Dental Abutments/classification , Dental Implants, Single-Tooth/classification , Dental Marginal Adaptation , Dental Stress Analysis , Humans , Materials Testing , Stress, Mechanical , Surface Properties , TorqueABSTRACT
Dental implantology has become an acceptable and effective treatment modality for totally and partially edentate alveolar arches. When teeth are extracted due to pathology or trauma, bone and soft tissue resorption often occurs. Either an immediate implant placement must be performed or a more traditional treatment plan must be determined; teeth for extraction or incorporation into the overall treatment scheme must also be selected. Selection of the implant site must reflect the mesiodistal, buccolingual, and apicocoronal dimensions. The responsibility of the implant team is to establish a correct diagnosis, evaluate clinical parameters, and design a comprehensive treatment plan, selecting the optimal time for implant placement. The learning objective of this article is to review three classifications of extraction sites and the time sequences of surgical protocols to implant placement following extraction.