Stress Distribution in Cortical Bone around the Basal Implant - A Finite Element Analysis.

AIM: The aim of the study was to develop a model that represents a basal implant with stress distribution in the cortical bone on application of loads emulating masticatory forces. MATERIALS AND METHODS: In this study, the stress distribution in the bone and the implant is evaluated by applying various loads that emulate the masticatory forces. The geometric models of cortical bone representing the premolar area and a basal implant model of the following specifications, longitudinal oval threaded pin (1.95 mm × 2.1/2.3 mm ø), height of the implant head (7.2 mm), and width of the implant head (3.5 mm) (BOI BS, IDHEDENTAL), were generated with Ansys software, and both the implant model and the bone model are superimposed to mimic the bone implant system as a unit. RESULTS: Overall comparison of stress distribution on both implant shaft and implant neck showed that maximum stresses are located at implant neck irrespective of forces applied and minimum stresses are located at implant shaft. On overall comparison of stresses seen within the bone and the implant, it was observed that the maximum stresses were seen in the implant neck followed by the implant shaft followed by the bone interface. CONCLUSION: The present study concluded that the stress transmission is greatest during application of oblique load (70 N) followed by horizontal load (10 N) and the least by vertical load (35 N).

Amaurosis, an Unusual Complication Secondary to Inferior Alveolar Nerve Anesthesia: A Case Report and Literature Review.

Ocular complications after an inferior alveolar nerve anesthesia are rare. These complications, although temporary and benign, can be distressing to both the patient and the clinician. A 37-year-old male patient was administered an inferior alveolar nerve block for the root canal treatment of tooth #30. Immediately after the administration of local anesthesia, the patient reported complete loss of vision. The patient recovered completely after 15 minutes. In particular, amaurosis is quite uncommon and usually heralds a more sinister pathology such as stroke. This case report presents an unusual case of ocular complication after an inferior alveolar nerve block. Adequate knowledge of the regional anatomy and physiology of the orbit and its nearby structures, the proposed causes of ocular complications, and prevention and management is necessary to manage such events.

Comparative evaluation of microleakage of mineral trioxide aggregate and Geristore root-end filling materials in different environments: An in vitro study.

AIM: The aim of this in vitro study was to evaluate and compare the microleakage of mineral trioxide aggregate (MTA) and Geristore root-end filling materials in different environments. MATERIALS AND METHODS: After removing the anatomical crowns of ninety extracted human maxillary central incisors, their root canals were instrumented and obturated. The apical 3 mm of each root was resected, and a standardized root-end cavity was prepared using an ultrasonic tip. The roots were alienated into three equal subgroups for each material and the root-end filling was performed in different environments namely dry, saliva contaminated, and blood contaminated. Samples were immersed in 0.2% Rhodamine B dye for 48 h. Roots were sectioned longitudinally and examined under a fluorescent microscope to measure the linear dye penetration. The results were statistically analyzed using analysis of variance and Tukey's honestly significant difference post hoc test. RESULTS: The Geristore dry group illustrated the lowest linear leakage, while the MTA saliva-contaminated group illustrated the highest leakage. In dry environment, linear dye penetration of both MTA and Geristore groups did not show any significant difference. However, statistically significant difference was observed between MTA and Geristore groups in blood- and saliva-contaminated environments. CONCLUSION: Geristore showed better results in saliva- and blood-contaminated environments; hence, Geristore may be used as an alternative to MTA for root-end filling.