Diagnosis and management of traumatically induced hemicrania continua and neuropathic pain secondary to facial gun shot wound.

Near fatal gunshot wound to the face results in lifesaving surgery and restorative procedures. Chronic pain followed. This is the probable first case report of posttraumatic hemicrania continua and its successful management.

Fracture Strength of Implant Screw-Retained All-Ceramic Crowns with the Use of the Angulated Screw Channel: A Pilot Study.

To correct for angulation discrepancies in the maxilla, implant companies have designed angulated screw channel (ASC) abutments. The design of these abutments allows for the restorative screw channel to be placed up to 25 degrees off the center axis of the implant. Minimal independent research has been published to evaluate the fatigue resistance of this implant-abutment connection. This study evaluated the fracture strength of a newly designed zirconia crown with a 25-degree angulated screw channel (n = 5) vs a straight channel (n = 5). Each specimen was subjected to an off-axis compression load from an MTS cyclic loading machine with a custom-designed indenter simulating a natural dentition. All the 25-degree angulated screw channel specimens failed, with four of the five (80%) catastrophically failing. Four of the five straight-channel specimens failed, with two of the five (40%) catastrophically failing. Results revealed the potential abutment fracture from internal stresses at the screw-zirconia and metallic-zirconia interfaces. Further research is needed to test the use of all-ceramic crowns with the use of the angulated screw channel.

Efficacy of Several Retightening Protocols for Maintaining Clamping Force in the Implant-Abutment Joint: An In Vitro Pilot Study.

PURPOSE: Stability of an implant-supported restoration is an ultimate measure of the success of the procedure. It has been recommended by some to retighten the abutment screw for maintenance of the crown on the implant. The purpose of this study was to evaluate the usefulness of two retightening protocols to maintain the clamping force. MATERIALS AND METHODS: Three groups of slip-fit implants (MIS 4.3 by 10.5) were compared. The first group was only tightened once (group C). In the second group (group R10M), the screw was retightened after 10 minutes. The third group (group R2W) was retightened after 2 weeks of simulated functional loading. After completion of individual protocols, all specimens were loaded for 100,000 cycles. After the loading, all specimens had the remaining torque audited. RESULTS: The mean torque loss for group C was 6.10 (± 5.13) Ncm. Group R10M was 2.03 (± 3.018) Ncm, and group R2W was 0.30 (± 0.483) Ncm. A one-way analysis of variance (ANOVA) recorded significant differences among the groups (P = .003). Multiple pairwise comparisons between groups by Tukey test recorded significant differences between group C vs group R10M (P = .035) and group C vs group R2W (P = .002). There was no significant difference in torque loss between groups R10M and R2W (P = .509). CONCLUSION: Within the parameters of this in vitro investigation, it was concluded that both retightening after 10 minutes (P = .035) and after 2 weeks (P = .002) was equally effective.

Fracture resistance of soft tissue level implants after cyclic loading and external modification.

STATEMENT OF PROBLEM: The exposure of the implant collar in the esthetic zone is a challenging complication of implant dentistry. The preparation of the exposed implant collar to create room for restorative material may decrease the strength of the abutment/implant assembly. PURPOSE: The purpose of this in vitro study was to evaluate the effect on the failure load of preparing a 0.5-mm chamfer finish line on an implant collar at various apical depths. MATERIAL AND METHODS: Thirty solid abutments and 30 implants were screwed into a customized metal mold at a 30-degree angle to the vertical axis. An intact group (IN) (control) (n=10) had no preparation, experimental group P1 had a 0.5-mm chamfer margin placed 1 mm apical to the implant/abutment interface, and experimental group P2 had the margin placed 2 mm apical. The specimens were subjected to a fatigue loading of 200 N for 1 000 000 cycles. Unfractured specimens were then loaded until failure. Mean fracture load (MFL) values were compared with 1-way ANOVA, and the Tukey test was used to identify differences among groups (α=.05). RESULTS: One specimen from both the IN and P1 groups and 2 specimens from the P2 group failed after fatigue loading. Significant differences in the MFL values were found between the IN group (3825) and P1 group (2944), P<.001 and between the IN group and the P2 group (2553), P<.001. CONCLUSIONS: The mean load required to fracture the abutment/implant assembly decreased significantly after various amounts of implant collar preparation.

Posttraumatic head injury resulting in spasticity disorders and oral injury: application of prosthodontic skills for tissue protection--a case report.

Patients who have experienced significant brain injury (such as hemorrhagic stroke or trauma) can suffer brain damage that leads to altered neurologic functioning. One such ill effect is the development of aberrant mandibular reflexes that may inflict serious trauma to oral and labial tissues. As primary oral health care providers, dental clinicians may be called upon to function as part of the medical team managing the patient. This case report reviews one such scenario in which the unique skills of trained specialists were used to provide a protective oral device to allow for tissue protection and healing.