Foreign body giant cell reaction related to placement of tetracycline-treated polylactic acid: report of 18 cases

The Effect of Terra-Cortril as Local Pain Medication on the Healing Process of a Fresh Extraction Socket: A Retrospective Cohort Study

(1) Background: Use of Terra-Cortril may reduce pain and discomfort after tooth extraction. It is widely used among dentists, especially for third molar extraction and for treatment of dry socket. Only few case reports described unsuccessful healing with formation of myospherulosis. (2) Aim: The primary objective of this retrospective cohort study was to compare the occurrence of unsuccessful healing between extraction sockets locally treated with Terra-Cortril (TC) (exposure cohort) and extraction sockets subjected to unassisted healing (non-exposure cohort). The assessment of the three-dimensional morphology of the bone was a secondary objective. (3) Material and methods: The records of patients who had one or more extractions between 1 January 2020 and 1 July 2021 followed by implant placement in one private practice were retrieved and data were extracted. At the time of implant placement, practitioners established, both clinically and radiographically, if the healing was successful or unsuccessful. Explanatory demographic as well as clinical variables were extracted from patient files, checked and supplemented by contacting patients in cases of missing data. (4) Results: 69 patients were included who had, in total, 99 extractions. The exposure cohort included 55 sites, while the non-exposure cohort included 44 sites. A total of 56 sites demonstrated successful healing, and 53 showed unsuccessful healing. The regression model identified TC as a significant predictor (p = 0.014) for unsuccessful healing with an odds ratio of 2.86. Sites treated with Terra-Cortril had a significantly greater bone defect at level -1 mm, level -3 mm, and level -5 mm from the bone crest, and significantly greater maximal vertical and horizontal bone defects. At sites where Terra-Cortril was used, significantly more surgical consequences were reported (70.91% vs. 18.18%, p < 0.001). (5) Conclusions: fresh extraction sockets treated with Terra-Cortril increased the likelihood of unsuccessful healing with an odds ratio of 2.86. The greater defect size leads to significantly more limitations when planning implants at sites previously treated with TC.

The preventive effect of medicinal herbal extract and gelatin sponge on alveolar osteitis: An in vivo micro-computed tomography and immunohistochemical analysis in rats

OBJECTIVE

The purpose of this study was to evaluate the preventive effect of medicinal herbal extract (MHE) and gelatin sponge on alveolar osteitis (AO) in an experimental rat model.

DESIGN

Twenty-one Sprague-Dawley male rats with a mean age of 12 weeks were used. After extraction of the maxillary right first molar, an AO model was created for each animal. The animals were randomly separated to three equal groups. Group I served as a control, Group II was subjected to an intra-alveolar MHE application, and gelatin sponge was left in the sockets of Group III. On the 7th post-extraction day, the animals were sacrificed. The specimens were analyzed by micro-computed tomography (micro-CT), histopathologically and immunohistochemically.

RESULTS

Macroscopic evaluation revealed mild to intense signs of AO in all groups, but the difference was not significant (p < 0.05). Micro-CT analysis showed that bone formation was the highest in Group III (bone volume/total volume; 10.63 ± 4.9 %), whereas bone mineral density was the highest in Group I (2.05 ± 0.2 g/cm³). The difference was not significant (p > 0.05). In Group III, only 16.7 % of specimens showed no signal of inflammatory response (p < 0.01). The difference was not significant between the positive labeling for receptor activator of nuclear kappa-β (RANK), receptor activator of nuclear kappa-β ligand (RANKL), osteoprotegerin and osteopontin, but the intensity of Groups II and III was higher than the Group I for osteopontin (p < 0.01).

CONCLUSIONS

MHE and gelatin sponge were not effective enough to prevent alveolar osteitis, but positive results were obtained in bone healing.

Myospherulosis of the Mandible Presenting as a Multilocular Lesion: A Case Report and Review of the Literature

Myospherulosis is an uncommon foreign body reaction that occurs in tissues exposed to antibiotic and oil-based ointments. Radiographic imaging of this lesion may suggest other diagnoses. Treatment consists of conservative surgical removal, and is usually curative. We report herein a case of myospherulosis presenting as an extremely unusual multilocular radiolucent lesion.

The effect of loading in regenerated bone in dehiscence defects following a combined approach of bone grafting and GBR

OBJECTIVES

To evaluate by histology the effect of loading on the regenerated bone at dehiscence type defects around implants when treated with a combined approach of bone grafting and guided bone regeneration (GBR).

MATERIALS AND METHODS

In twelve Göttingen mini-pigs, the lower premolars and first molars were extracted and the alveolar process was reduced in width. After 3 months, two Straumann SLActive (Straumann AG, Basel, Switzerland) implants were placed in each hemi-mandible. Twelve implants were placed into the reduced alveolar ridge (group P) with no further defect or treatment on the site, while on 36 implants, buccal dehiscence defects were created and treated as follows: Group T1: synthetic bone substitute (Straumann Bone Ceramic, SBC, Straumann AG). Group T2: SBC with a polyethylene glycol membrane (Straumann MembraGel, Straumann AG); Group N: the dehiscence remained untreated. Three months following implantation, long, custom-made, healing abutments were placed in one hemi-mandible only to ensure functional loading. After 2 months, histological analysis was performed.

RESULTS

A trend for lower residual defect height and higher bone-to-implant contact was observed in the loaded sites compared with non-loaded sites in groups P, T1 and N. In group T2, the opposite effect was observed. In terms of bone formation, sites treated with SBC grafting and GBR (group T2) exhibited the largest surface area of regenerated bone followed by T1 and N. Significant resorption of the graft particles was noted in group T2 and the graft surface area occupied by SBC was significantly higher in group T1 compared with group T2 (P < 0.05).

CONCLUSIONS

Loading may have a positive effect on bone-to-implant contact in implants inserted in pristine bone or inserted in dehiscence sites and treated by grafting/no grafting.

Case report: late complication of a dry socket treatment

Dry socket is often treated in dentistry with intra-alveolar dressings; the use of them remains controversial and has been related to some side effects such as neuritis, foreign body reactions, and myospherulosis. We present a case of an intra-alveolar dressing (zinc-oxide eugenol paste) that mimicked a trigeminal neuralgia for 3 years and caused a right maxillary chronic osteomyelitis and foreign body reaction in a zone corresponding to the alveolus of the maxillary first molar. This long-term complication was successfully managed by complete removal of the foreign body and curettage of the affected area.

Alveolar osteitis: a comprehensive review of concepts and controversies

Alveolar osteitis, "dry socket", remains amongst the most commonly encountered complications following extraction of teeth by general dentists and specialists. A great body of literature is devoted to alveolar osteitis addressing the etiology and pathophysiology of this condition. In addition numerous studies are available discussing methods and techniques to prevent this condition. To this date though great controversy still exists regarding the appropriate terminology used for this condition as well as the actual etiology, pathophysiology, and best methods of prevention and treatment. This article is a comprehensive critical review of the available literature addressing the concepts and controversies surrounding alveolar osteitis. We aim to assist the dental health care professional with patient preparation and management of this commonly encountered postoperative condition should be encountered.

Clinical concepts of dry socket

Dry socket is one of the most studied complications in dentistry, and a great number of studies have searched for an effective and safe method for its prevention and treatment. One of the great clinical challenges since the first case was reported has been the inconsistency and differences in the various definitions of dry socket and the criteria used for diagnosis. The pathophysiology, etiology, prevention, and treatment of dry socket are very important in the practice of oral surgery. The aim of the present report was to review and discuss each aspect.

The efficacy of a topical anesthetic gel in the relief of pain associated with localized alveolar osteitis

PURPOSE

This prospective randomized clinical study assessed the efficacy of pain control for postextraction alveolar osteitis comparing the use of eugenol on a gauze strip versus a thermosetting gel containing 2.5% prilocaine and 2.5% lidocaine.

PATIENTS AND METHODS

Thirty-five patients who presented with postextraction alveolar osteitis were randomly assigned to either a control group or test group. After irrigation of the extraction site with normal saline solution, the control patients were treated with eugenol on a gauze strip placed in the socket and the test patients were treated with the thermosetting gel placed directly into the socket. All patients were given a series of visual analog scales to record their pretreatment pain and post-treatment pain at 5, 10, and 15 minutes and then at 1-hour increments during waking hours for the next 48 hours. They were also given a prescription for an analgesic to use for breakthrough pain during the 48-hour period, if necessary, and instructed to record the dose and timing of any pain medication taken. All patients were seen for follow-up at 48 hours after treatment.

RESULTS

The mean pretreatment pain score was 6.72 on a scale ranging from 1 to 10 for the eugenol group and 6.37 for the prilocaine-lidocaine group (SE, 0.46), and the 2 groups were not different (P = .62). In the immediate post-treatment period (0-15 minutes) the pain levels were significantly reduced in both groups (Ps < .001). However, the thermosetting gel produced a significantly greater reduction in pain (mean, 3.23; SE, 0.62) than the eugenol (mean, 4.83; SE, 0.43) (P = .022). Over the next 48 hours, the pain level was nominally less with the thermosetting gel, but this difference was not statistically significant (Ps = .2).

CONCLUSION

Although the efficacy of the 2 treatments was not significantly different, the nominal superiority and ease of using the thermosetting gel warrant further investigation.

Dry socket: a prospective study of prevalent risk factors in a Nigerian population

PURPOSE

To identify major risk factors for developing dry socket in some Nigerians, and to formulate a nonpharmacologic protocol for its effective prevention.

PATIENTS AND METHODS

Patients presenting with dry socket at the Oral Surgery Clinic of the Obafemi Awolowo University Teaching Hospital, Ile-Ife, Osun State, Nigeria, over an 18-month period were studied. Biographic data, preoperative diagnoses, teeth extracted, oral hygiene status, and history relevant to the extractions and presentations of dry socket were documented. Procedures were classified as traumatic or atraumatic. Data were analyzed using SPSS version 11.0 (SPSS Inc, Chicago, IL) with simple descriptive statistics and the chi(2) test, as appropriate. P <or= .05 was considered significant.

RESULTS

Sixty-eight extraction sockets in 65 patients (46 females and 19 males) with a mean age of 33.48 (+/-SD 13.5) years were studied. All extracted teeth were posterior (17 maxillary, and 51 mandibular). Preoperative diagnoses were mainly of acute apical periodontitis secondary to carious lesion (30/68), chronic apical periodontitis (18/68), and chronic pulpitis (15/68). The use of an oral contraceptive was elicited in 25% of the females, and extractions were performed between days 1 and 22 of their menstrual cycle. Extraction was traumatic in 66.2% of cases. A ranking of the elicited risk factors suggests that a previously infected posterior tooth involves an equal risk in both genders. Poor oral hygiene and traumatic extraction in a mandibular tooth were prominent in males, whereas extractions performed between days 1 and 22 of the menstrual cycle were significant in females.

CONCLUSION

Control of preoperative infection, insistence on good oral hygiene, avoidance of trauma, and avoidance of surgery on days 1 to 22 of the menstrual cycle in nonmenopausal women may reduce the incidence of dry socket in the study population.

Biocompatibility issues with modern implants in bone - a review for clinical orthopedics

Skeletal defects may result from traumatic, infectious, congenital or neoplastic processes and are considered to be a challenge for reconstructive surgery. Although the autologous bone graft is still the “gold standard”, there is continuing demand for bone substitutes because of associated disadvantages, such as limited supply and potential donor side morbidity [1]. This is not only true for indications in orthopedic and craniomaxillofacial surgeries, but also in repairing endodontic defects and in dental implantology.

Before clinical use all new bone substitute materials have to be validated for their osseoconductive and - depending on the composition of the material also –inductive ability, as well as for their long-term biocompatibility in bone. Serving this purpose various bone healing models to test osteocompatibility and inflammatory potential of a novel material on one hand and, on the other hand, non-healing osseous defects to assess the healing potential of a bone substitute material have been developed. Sometimes the use of more than one implantation site can be helpful to provide a wide range of information about a new material [2].

Important markers for biocompatibility and inflammatory responses are the cell types appearing after the implantation of foreign material. There, especially the role of foreign body giant cells (FBGC) is discussed controversial in the pertinent literature, such that it is not clear whether their presence marks an incompatibility of the biomaterial, or whether it belongs to a normal degradation behavior of modern, resorbable biomaterials.

This publication is highlighting the different views currently existing about the function of FBGC that appear in response to biomaterials at the implantation sites. A short overview of the general classes of biomaterials, where FBGC may appear as cellular response, is added for clarity, but may not be complete.

Effectiveness of chlorhexidine gel versus chlorhexidine rinse in reducing alveolar osteitis in mandibular third molar surgery

PURPOSE

Chlorhexidine is an antimicrobial agent used in the prevention of postextraction alveolar osteitis, tooth decay, and periodontal diseases. There are various forms of chlorhexidine application. The most extensively studied is one that uses the rinse as the form of application. Recently, a bioadhesive gel form has become available. Its main advantage is that it prolongs the bioavailability of chlorhexidine in the application area. The purpose of this study was to compare the effectiveness of chlorhexidine gel versus a chlorhexidine rinse in reducing postoperative alveolar osteitis after the extraction of mandibular third molars.

MATERIALS AND METHODS

The experimental or gel group (n = 41) applied the bioadhesive 0.2% chlorhexidine gel to the wound during the first postoperative week and a control or rinse group (n = 32) used a 0.12% chlorhexidine rinse during the first week postextraction.

RESULTS

We observed a 70% decrease in postoperative alveolar osteitis in the gel group (P = .040). The rinse group had 25% incidence postoperative alveolar osteitis, while the gel group had 7.5%.

CONCLUSIONS

It was concluded that the topical application of bioadhesive chlorhexidine gel to the surgical wound during the postoperative week may decrease the incidence of alveolar osteitis after extraction of the mandibular third molars.

Impact of topical minocycline with third molar surgery on clinical recovery and health-related quality of life outcomes

PURPOSE

Compare recovery for clinical and health-related quality of life (HRQOL) outcomes after third molar surgery in patients treated with or without topical minocycline at surgery.

PATIENTS AND METHODS

Sixty-three patients at least 18 years of age with all 4 third molars below the occlusal plane were treated with topical minocycline during third molar surgery. Topical minocycline (1.0 mg in bioresorbable polyglycolide-co-dl-lactide [PGLA] sustained-release microspheres) was placed sequentially in bony defects after removal of lower third molars. Clinical and health-related quality of life (HRQOL) outcomes of these patients postsurgery were compared with those of a nonconcurrent control group (n = 60 patients) who did not receive antibiotics. The control group was selected using the same criteria and treated under the same surgical protocol as the antibiotic group. Differences between the groups were assessed with Cochran-Mantel-Haenszel row mean score statistics.

RESULTS

The 63 patients in the minocycline group were treated at 4 clinical centers. The incidence of delayed clinical recovery, defined as a postsurgery visit with treatment, was significantly lower in the minocycline group compared with the control group. In the minocycline group, 10% had 1 postsurgery visit with treatment; no patient had 2 visits. In the control group without antibiotics, 28% had at least 1 postsurgery visit with treatment (P = .01) and 13% had at least 2 postsurgery visits with treatment. Recovery time to "no" or "little trouble" with chewing and mouth opening was significantly improved in the minocycline group (P < .05).

CONCLUSIONS

Administration of topical minocycline with third molar surgery may improve clinical and HRQOL recovery in healthy adult patients with all 4 third molars below the occlusal plane, a presenting characteristic that has been suggested as a risk factor for delayed recovery.

The prevention of 'dry socket' with topical metronidazole in general dental practice

OBJECTIVE

The purpose of the study was to determine if the intra-alveolar application of topical metronidazole gel could reduce the incidence of alveolar osteitis (dry socket) following routine tooth extraction in molar and premolar extraction sites.

DESIGN

This was a multicentre, double blind, randomised, placebo-controlled clinical trial. A total of 302 patients took part, of which 23 returned with alveolar osteitis. Of these, eight had received the metronidazole gel and 15 the placebo.

SETTING

The study was carried out in three general dental practices by general dental practitioners working in England over the period 2000-2003.

MAIN OUTCOME MEASURES

Following extraction of either a molar or premolar tooth, either a 25% metronidazole gel or KY Jelly was syringed gently into the socket. A painful post operative complication was recorded if either a dry socket was present or the patient returned with pain.

RESULTS AND CONCLUSIONS

The difference in the incidence of alveolar osteitis between the placebo and the active gel groups was not significant and it was concluded that 25% topical metronidazole gel was not effective in reducing the incidence of alveolar osteitis. It was found that the incidence of alveolar osteitis reduced with increasing age and was more likely to occur in a patient with a previous history of the condition.

A comparative study of barrier membranes as graft protectors in the treatment of localized bone defects. An experimental study in a canine model

Guided bone regeneration is a predictable and well-documented surgical approach for the treatment of deficient alveolar ridges prior to endosseous implant placement. The purpose of this study was to compare a new resorbable membrane (GORE RESOLUT ADAPT Regenerative Membrane, i.e. 67% glycolide (PGA) : 33% trimethyline carbonate (TMC)) with Bio-Gide, a resorbable collagen membrane. Five canines were used in the study. Three saddle-type osseous defects were created bilaterally in edentulous areas of the mandible. The defects were filled with assayed, canine demineralized freeze-dried bone (DFDB) in a thermoplastic gelatin matrix. Using a randomized block design, four sites were covered with PGA : TMC membranes of four different porosities, one site was covered with a collagen membrane and one site consisted of DFDB alone (control). At 3 months, the animals were euthanized and the mandibles were removed en bloc for laboratory processing. A total of 30 sites were reviewed microradiographically and underwent histomorphometric analysis for bone regeneration, soft tissue presence and remaining graft material. All sites exhibited uneventful healing. A significantly higher percentage of bone regeneration was seen in the sites protected by the PGA : TMC membrane. A higher component of soft tissue was visible beneath the collagen membrane as compared with the PGA : TMC membrane. The control sites exhibited noticeable deformation of the regenerated bone secondary to collapse of the overlying periosteum. The authors conclude that the PGA : TMC membrane protected the DFDB-filled defect and allowed a greater amount of bone regeneration than the defect protected by the collagen membrane or the control.

Tetracycline compound placement to prevent dry socket: a postoperative study of 200 impacted mandibular third molars

PURPOSE

Our objective was to study whether the placement of intra-alveolar tetracycline prevents dry sockets or improves the postoperative period.

PATIENTS AND METHODS

A comparative clinical study of the surgical removal of 200 impacted mandibular third molars is made, with particular reference to postextraction pain, inflammation, trismus, and the incidence of dry socket. In 50% of these cases, a pharmacologic preparation that includes tetracycline was placed in the socket after removal of the impacted molar.

RESULTS

Dry socket was diagnosed in 4 cases (2%), with no relation to intra-alveolar tetracycline placement being observed. The patients who were administered intra-alveolar tetracycline had less pain and trismus and consumed fewer analgesics than the patients who received no such treatment, although statistical significance was not reached.

CONCLUSIONS

The intra-alveolar placement of tetracycline compound after the surgical removal of impacted mandibular third molars did not affect the incidence of dry socket.

The early tissue response to titanium and LactoSorb screws

Fractures of the maxillofacial region are common in the elderly people. Titanium and LactoSorb screws are the widely accepted materials for use in the maxillofacial fractures. This study was undertaken to evaluate the early tissue response following the insertion of both titanium and LactoSorb screws composed of 82% PLLA and 18% PGA in an elderly animal model. In this study, 22 titanium and 22 LactoSorb screws were applied to calvaria of 44 guinea pigs that were 10-11 months old. Animals were sacrificed on postoperative days 3, 7, 14, 30 and 60. Screws were retrieved with surrounding bone tissue and the specimens were prepared for routine histologic examination. All the specimens were evaluated by light microscopy. Histometric analysis revealed that there was no significant difference between LactoSorb and titanium screws for the new bone formation. The biodegradation of LactoSorb screws was not complete by the end of day 60. In conclusion, both materials were well tolerated and induced bone formation without causing adverse tissue response in an elderly animal model. Our results suggest that both LactoSorb and titanium miniplates and screws can be used safely, regardless of the increasing age. However, LactoSorb may be the first choice as it does not require a second operation for removal and has late biodegradation in elderly that keeps its support for a relatively longer time during fracture healing.

Contemporary views on dry socket (alveolar osteitis): a clinical appraisal of standardization, aetiopathogenesis and management: a critical review

The objective of this article is to harmonize descriptive definitions for the condition known as alveolar osteitis and to critically review and discuss the aetiology and pathogenesis of alveolar osteitis. In addition, the need for the identification and elimination of risk factors as well as the preventive and symptomatic management of the condition are discussed. The aim of this critical review is to provide a better basis for clinical management of the condition. A meta-analysis of data was not done.

Reduction in the incidence of alveolar osteitis in patients treated with the SaliCept patch, containing Acemannan hydrogel

PURPOSE

In the present study, we compared the incidence of alveolar osteitis (AO) in patients treated with either clindamycin-soaked Gelfoam (Pharmacia and Upjohn Co, Kalamazoo, MI) or SaliCept Patches (Carrington Laboratories, Inc, Irving, TX). The SaliCept Patch is a freeze-dried pledget that contains Acemannan Hydrogel (Carrington Laboratories) obtained from the clear inner gel of Aloe vera L.

PATIENTS AND METHODS

A retrospective evaluation was performed of the records of 587 patients (1,031 sockets) whose extraction sites had been treated with clindamycin-soaked Gelfoam. A prospective trial was conducted in which 607 patients (1,064 sockets) had 2 SaliCept Patches placed immediately after extraction. The same surgeon treated all patients.

RESULTS

Analysis restricted to mandibular third molar sites showed that 78 of 975 sites (8.0%) in the Gelfoam group developed AO, whereas only 11 of 958 sites (1.1%) in the SaliCept group developed AO (P <.0001). Further analysis of all extraction sites revealed that the incidence of AO in the Gelfoam group was 7.6% compared with 1.1% in the SaliCept-treated group (P <.0001).

CONCLUSIONS

The study results suggest that the SaliCept Patch significantly reduces the incidence of AO compared with clindamycin-soaked Gelfoam.

Alveolar osteitis prevention by immediate placement of medicated packing

OBJECTIVE

The purpose of this study was to evaluate whether immediate placement of medicated dry socket packing would decrease the incidence of alveolar osteitis (dry socket) with lower third molar extractions.

STUDY DESIGN

In 100 patients, 200 lower third molars were extracted. One half of the sockets were packed to the crest of the alveolar ridge with a one-quarter-inch radiograph-detectable filament gauze that contained 9% eugenol, 36% balsam of Peru, and 55% petroleum jelly. The medicated packing was removed 1 week after surgery. None of the patients were taking antibiotics. Patients were instructed to increase their oral hygiene before and after surgery and were to use 0.12% chlorhexidine gluconate 2 days before and 3 days after surgery. RESULTS; Two hundred bilateral lower third molars of varying difficulty were extracted. The overall alveolar osteitis rate was 34 (17%). The immediately packed lower third molar sites had an alveolar osteitis rate of 8 (8%). The sockets that were not packed with medicated packing the day of surgery had an alveolar osteitis rate of 26 (26%). The difference was statistically significant (P =.001).

CONCLUSION

The results of this study suggest that placement of medicated dry socket packing immediately after lower third molar extraction decreases the alveolar osteitis rate.

The future of biodegradable osteosyntheses

In the last 3 decades, much progress has been made in the development of biodegradable osteosyntheses. Despite this progress, these materials are still only used in small numbers, and the scope of their application has been limited. The limitations of biodegradable osteosyntheses mainly are related to problems with their mechanical properties and, in particular, biocompatibility. These problems need to be solved so that biodegradable osteosyntheses can perform up to their full potential and thus, eventually, make their general clinical application routine. This paper presents a historical perspective on the development of biodegradable osteosyntheses, discusses the successful developmental achievements and the still-existing problems, and gives a perspective on their future development.

Dental extraction wound management: medicating postextraction sockets

The rather impressive percentage of extraction sites undergoing clot loss and deranged healing results in significant morbidity for the patient and frequent visits to the surgeon to effect relief of discomfort, most often by the use of anodyne dressings. The amount of work lost by patients needing such palliative treatment, and loss of productive time for the surgeon, translate into an unknown, but potentially large, economic loss to society. This would mandate that economical methods of ensuring normal extraction socket healing with minimal morbidity be developed. The most useful socket medicaments to prevent socket healing derangements would include broad-spectrum antibiotics, specifically clindamycin and tetracycline. Not discussed in this article, but possibly germane to the subject of clot stabilization and healing, is consideration of resorbable substances such as gelatin sponge, polylactic acid, and methylcellulose as clot-stabilizing socket implants. The record of such substances in preventing AO is mixed, but the combinations of these inexpensive materials with topical socket medicaments may yield a decreased tendency for clot lysis and greater mechanical strength to the bulk blood clot, as has been demonstrated with difficult mandibular third molar impactions in one study involving polylactic acid, tetracycline, and hydrocortisone.

Particulate retrieval of hydrolytically degraded poly(lactide-co-glycolide) polymers

This article describes a technique for the retrieval of polymeric particulate debris following advanced hydrolytic in vitro degradation of a biodegradable polymer and presents the results of the subsequent particle analysis. Granular 80/20 poly(L-lactide-co-glycolide) (PLG) was degraded in distilled, deionized water in Pyrextrade mark test tubes at 80 degrees C for 6 weeks. Subsequently, a density gradient was created by layering isopropanol over the water, followed by a 48-h incubation. Two opaque layers formed in the PLG tubes, which were removed and filtered through 0.2-micrometer polycarbonate membrane filters. In addition, Fourier transform IR spectroscopy (FTIR) was performed to confirm the presence of polymer in the removed layers. The filters were gold sputter coated, and scanning electron microscopy (SEM) images were made. FTIR analysis confirmed that the removed material was PLG. SEM images of the extracts from the upper (lowest density) opaque layer showed a fine, powderlike substance and globular structures of 500-750 nm. The SEM images of the lower (highest density) opaque layer showed particles with a crystalline-like morphology ranging in size from 4 to 30 micrometer. Particulate PLG debris generated with the described technique can be useful for further studies of its biological role in complications associated with poly(alpha-hydroxy)ester implants. This study shows the presence of very persistent nano- and microparticles in the degradation pathway of PLG.

A case of myospherulosis occurring in the perirenal adipose tissue

The authors report a case of spontaneous myospherulosis that developed in the right perirenal adipose tissue, presented like an abscess, in an 82-year old man of the A, Rh+ blood group. The patient had a history of chronic lymphocytic leukaemia. Fine needle aspiration and histological examination of the renal cyst allowed the observation of 4- to 7-micron spherules (or endobodies) enclosed in saccular structures (or parent bodies) and accompanied by a foreign body-type response. The walls of the parent bodies were negative for PAS, Gomori's methenamine silver and Giemsa's stain. Immunohistochemical study was positive with anti A antibody specific of A1/A2 blood group and with anti glycophorin A antibody. The authors reviewed the literature concerning this rare lesion: it usually occurs in subcutaneous fat or in the paranasal sinuses, nose and middle ear but, up to now, no previous case has ever been reported in the urinary tract. The only case of visceral myospherulosis previously reported occurred in a cystic teratoma of the ovary. The reported case is also peculiar by the unusual thickness of the parent bodies. The authors also discuss the mechanism of the disease and suggest that, in the present observation, myospherulosis could have been induced by the rupture of a preexisting cyst in the perirenal adipose tissue.

Experimental topical tetracycline-induced neuritis in the rat

PURPOSE

Recent studies have reported that tetracycline may induce chronic inflammatory responses in the adjacent soft tissues. The purpose of the present study was to determine if dry, powdered tetracycline evoked an inflammatory response in nerve tissue.

MATERIALS AND METHODS

Twenty male Sprague-Dawley rats were anesthetized and bilateral mental nerves were exposed. Half of the 40 nerves were intentionally injured by removing the epineurium, and the remaining nerves were uninjured. In a prospective, randomized, double-blind manner, equal volumes of color-matched, precoded tetracycline powder or Gelfoam (Upjohn, Kalamazoo, MI) powder control was placed in intimate contact with the nerves and sealed in polyethylene tubes. Forty-five days later the animals were killed and 5-micron sections of the nerves were prepared for histologic examination. The presence of epineurium, fascicular number, and fascicular area were measured. An inflammatory response in nerve tissue and the intrafascicular and epifascicular inflammatory index was measured by counting darkly stained nuclei with a Jandel Video Analysis System (Jandel Scientific, Corte Madera, CA).

RESULTS

Experimental injury (ie, epineurectomy) of nerves resulted in a statistically significant increase in fascicular number (P = .034), but not in fascicular area. For the intrafascicular inflammatory index, there was a significant main effect for drug (P = .002) and injury (P = .002). Experimental injury in both Gelfoam control and tetracycline grouped nerves resulted in an increase in intrafascicular inflammation. There was no significant increase in intrafascicular inflammation in either Gelfoam control or tetracycline grouped nerves when the epineurium was intact. The combination of both tetracycline and epineurectomy resulted in the largest increase in intrafascicular inflammation found among the groups studied. For epifascicular inflammatory index, there was a significant main effect for drug (P = .003) and injury (P = .001) that mirrored the intrafascicular inflammatory pattern.

CONCLUSION

The results of the present study suggest that dry, powdered tetracycline accentuates the inflammatory response in intrafascicular and epifascicular nerve tissue following epineurectomy. The maintenance of epineurium inhibited the inflammatory response in intrafascicular and epifascicular nerve tissues. Gel-foam was an inert material when placed against exposed nerve tissue. These findings suggest that tetracycline should not be placed in extraction sockets when injury of the inferior alveolar and/or lingual nerves are present.

Foreign body reactions to resorbable poly(L-lactide) bone plates and screws used for the fixation of unstable zygomatic fractures

In a previous article in the Journal of Oral and Maxillofacial Surgery, the initial results of treating 10 patients with solitary, unstable, displaced zygomatic fractures using resorbable poly(L-lactide) (PLLA) plates and screws was reported (Bos et al, 1987). This article describes the long-term results in these patients. Three years postoperatively, four patients returned because they were concerned about an intermittent swelling at the site of implantation. The remaining patients were recalled after the same postoperative period. All patients were examined clinically, and six patients were operated on again for evaluation of the swelling and to investigate the nature of the tissue reaction. The explanted material showed remnants of degraded PLLA surrounded by a dense fibrous capsule. The swelling was classified as a nonspecific foreign body reaction to the degraded PLLA material. Ultrastructural investigation of the degraded material showed an internalization of crystal-like PLLA material in the cytoplasm of various cells.

Concentration of cefuroxime in mandibular alveolar bone following a single preoperative dose

A pilot study was undertaken on 12 patients undergoing the bilateral removal of impacted mandibular wisdom teeth to determine the level of cefuroxime sodium within the alveolar bone adjacent to the third molar teeth following a single preoperative intravenous administration. The results indicated that a single 1.5 g intravenous bolus injection provided satisfactory alveolar bone concentrations for routine antibiotic prophylaxis at the time of wisdom tooth removal.