Trephine Drill Research Articles

A microradiographic investigation of cancellous bone healing after irradiation and hyperbaric oxygenation: a rabbit study

Purpose: To analyze the effect of irradiation on cancellous bone healing at different times after irradiation and to study if hyperbaric oxygen therapy (HBO) would affect the bone healing capacity, when delivered directly after irradiation. Methods and Materials: Rabbits were given a single dose of 15 Gy 60Co radiation to one hind leg, the other hind leg serving as control. A standardized defect through the femoral metaphysis of the rabbits was created by a trephine drill biopsy at different times after irradiation. New bone formation in the defect was evaluated by a new biopsy through the previous defect after a healing time of 8 weeks. The mineral contents of the biopsies were analyzed by microradiography and microdensitometry. Results: There was a large variation in the bone-forming capacity expressed as bone mineral content between the animals. No statistically significant differences could be detected regarding the effect of irradiation, HBO, or delayed surgery. Qualitative histology revealed more pronounced inflammation, fibrosis, and bone resorption in the irradiated bone. Conclusions: No definite conclusions can be drawn from the results of this study, however it might be hypothesized that cancellous bone recovers faster than cortical bone from radiation trauma.

Predetermined implant positioning by means of a novel guide template technique.

This paper presents a novel guide template technique for implant placement. In esthetic implant dentistry with its restoration-driven implant placement as well as in complete-arch cases with multiple implants, the precise positioning and angulation of dental implants is crucial for achieving the desired prosthetic results. Difficulties in implant positioning may arise especially with grafted jaws resulting from communication problems between surgeon and prosthodontist. This method may alleviate some of the problems common to conventional template techniques, where the drill is usually directly guided by the template. The key idea is to fixate the implant position and angulation by the help of Kirschner wires which are inserted in the alveolar ridge right through the mucosa before elevation of a mucoperiosteal flap. Thanks to this sequence, the template for guiding the wires may be positioned precisely, even on grafted edentulous ridges. After the insertion of the wires, the bone is exposed and the implant cavities prepared with a trephine drill guided over the wires alone or over wires combined with a special guidance cylinder fitting the trephine drill. The method may be combined with different planning and radiological techniques. Since the use of the template is detached from the actual drilling process, the danger of introducing debris of plastic or metal into the preparation site may be avoided. The present technique might be helpful for difficult cases by improving communication between prosthodontist and surgeon and also render additional security to the surgeon with less routine in dental implant insertion.

Reconstruction of calvarial defects by bioresorbable ceramics: an experimental study in rats

This study evaluated bioresorbable ceramics in the reconstruction of calvarial defects. Full-thickness defects were made in the calvaria of 40 adult Sprague-Dawley rats (350-450 g) with a standard 8-mm trephine drill. Three different materials were used for defect repair: (a) pure alpha-tricalcium phosphate (TCP), (b) surface-treated glass ceramic, (c) surface-treated glass ceramic plus 70/30 L/DL polylactic acid (volume ratio 45/55). The implants were pellets of 7.9 mm diameter and 2 mm thickness and were inserted press fit into the calvarial defects. Each of these materials was inserted into ten animals. Five animals were evaluated each after 6 weeks and 26 weeks. For each interval there was a control group of five animals. After 6 weeks the control defects exhibited negligible bone regeneration at the defect margins but showed substantially more bone regeneration after 26 weeks extending up to 2.5 mm into the defect space. The TCP specimens showed a number of multinuclear cells on the material surface and direct bone/implant contact in a few locations but no signs of gross degradation or volume reduction after 6 weeks. The amount of bone ingrowth and cellular behavior had not changed after 26 weeks with resorption still going on. Glass ceramic implants by contrast appeared to be even better tolerated after 6 weeks with remarkable bone ingrowth and broad osseous fixation of the pellet to the defect margins and beyond, while highly vascular connective tissue filled the remaining pores of the implant. After 26 weeks the material had been extensively degraded, leaving behind only a few remnants, which were surrounded by seams of highly vascularized and cell-rich resorptive connective tissue with newly formed bone tissue nearly bridging the defect. The polylactic acid/ceramic composite implants showed hardly any tissue ingrowth or degradation either after 6 or after 26 weeks. Hence all tested materials appeared to be well tolerated at the site of implantation. However, gradual replacement by bone ingrowth tended to occur only in implants without polylactic acid.

Algae-derived (phycogene) hydroxylapatite: A comparative histological study

3 granular hydroxylapatite (HA) biomaterials, solid, coralline and phycogene HA (obtained from calcifying algae), differing widely in their relative amounts of specific surfaces and their origin, were examined with regard to their effects on bone healing in rats. Trephine drill holes were produced in the rat femur and filled with the HA granules. Each biomaterial produced a characteristic pattern of bone healing. Bioceramics with a small surface area showed random bone-implant contacts. Biomaterials offering large surface areas showed a dense bone-implant interface. Evidence is presented to suggest that a large specific surface favours osteoneogenesis and cell spreading on and into an implant.

Algae-derived (phycogene) hydroxylapatite: A comparative histological study

3 granular hydroxylapatite (HA) biomaterials, solid, coralline and phycogene HA (obtained from calcifying algae), differing widely in their relative amounts of specific surfaces and their origin, were examined with regard to their effects on bone healing in rats. Trephine drill holes were produced in the rat femur and filled with the HA granules. Each biomaterial produced a characteristic pattern of bone healing. Bioceramics with a small surface area showed random bone-implant contacts. Biomaterials offering large surface areas showed a dense bone-implant interface. Evidence is presented to suggest that a large specific surface favours osteoneogenesis and cell spreading on and into an implant.

Trephine drill biopsy of the lung. Cleveland clinic experience

Trephine drill biopsy of the lung. Cleveland clinic experience

Drill Lung Biopsy

To the Editor.— Your article in the Medical News section of the March 5, 1973 issue regarding the experience with drill lung biopsy prompted me to write you describing our experience with this procedure at the Cleveland Clinic Foundation. During the period between August 1969 and May 1970, Dr. D. Aughenbaugh and I performed 50 lung biopsies using the trephine drill instrument. All patients fit into the category of diffuse lung disease; however, we did not consider the presence of pulmonary hypertension as a contraindication to the procedure. The complications were as follows: one hemothorax; four pneumothorax requiring suction (most of the patients developed small pneumothorax that were reabsorbed spontaneously); and one death. I should mention that the patient who died had undiagnosed diffuse lung disease with severe hypoxemia and was not considered a candidate for open lung biopsy. Therefore, it was thought that this procedure was necessary to obtain