Harnessing the Near-Peer Effect in Anatomy Education.

Benefits of near-peer teaching are well-documented, but its time requirements can be prohibitive. We integrated the near-peer effect into a clinical anatomy course with weekly student-developed handouts vetted by faculty to provide an element of near-peer teaching without the burden of extra time.

Essential Oil Profile and Yield of Corolla, Calyx, Leaf, and Whole Flowering Top of Cultivated Lavandula angustifolia Mill. (Lamiaceae) from Utah.

Lavandula angustifolia Mill. (lavender) is an essential-oil-bearing plant in the Lamiaceae family. Volatile oil produced through the steam distillation of lavender was examined to establish the essential oil yield and aromatic profile from each portion of the plant-namely, the corolla, calyx, leaf, and whole flowering top. The resulting essential oils were analyzed by GC-FID and GC-MS. The different plant parts generally shared similar compounds but in varying relative percentages. Aromatic profiles of the whole flowering top and calyx were similar, with prominent compounds being linalool acetate (34.3%, 32.0%), linalool (26.5%, 32.9%), lavandulyl acetate (5.6%, 4.9%), terpinen-4-ol (5.3%, 7.0%), and (Z)-ß-ocimene (4.5%, 5.4%), respectively. Aromatic profiles for the corolla and leaf were unique. Prominent aromatic compounds of the corolla included linalool acetate (18.4%), linalool (10.8%), epi-α-cadinol (10.0%), borneol (7.3%), and lavandulyl acetate (6.3%). Prominent aromatic compounds of the leaf included epi-α-cadinol (19.8%), γ-cadinene (11.0%), borneol (6.0%), caryophyllene oxide (4.9%), and bornyl acetate (4.8%). Complete profiles and essential oil yields of corolla, calyx, leaf, and whole flowering top were established. This study establishes the influence the corolla, calyx, and leaf exert on the aromatic profile of the whole flowering top and provides insight into authentication of lavender essential oil.

The interactive roles of mastery climate and performance climate in predicting intrinsic motivation.

This study examined the interplay between perceived mastery and performance climates in predicting increased intrinsic motivation. The results of a two-wave longitudinal study comprising of 141 individuals from three military academies revealed a positive relationship between a perceived mastery climate and increased intrinsic motivation only for individuals who perceived a low performance climate. This finding suggests a positive relationship between a perceived mastery climate and increased intrinsic motivation only when combined with low perceptions of a performance climate. Hence, introducing a performance climate in addition to a mastery climate can be an undermining motivational strategy, as it attenuates the positive relationship between a mastery climate and increased intrinsic motivation. Implications for future research and practice are discussed.

Epithelial IL-1R2 acts as a homeostatic regulator during remission of ulcerative colitis.

Ulcerative colitis (UC) is a chronic intestinal inflammatory disease that may undergo periods of activity followed by remission. We aimed to identify the endogenous regulatory mechanisms that may promote disease remission. Transcriptional and protein analysis of the intestinal mucosa revealed that the IL-1 decoy receptor, interleukin-1 receptor type 2 (IL1R2), was upregulated in remission compared with active UC and controls. We identified epithelial cells as being responsible for increased IL-1R2 production during remission. Expression of IL1R2 was negatively regulated by Wnt/beta-catenin signals in colonic crypts or epithelial stem cell cultures; accordingly, epithelial stem cells upregulated IL-1R2 upon differentiation. Blocking IL-1R2 in isolated colonic crypt cultures of UC patients in remission and T-cell cultures stimulated with biopsy supernatant from UC patients in remission boosted IL-1ß-dependent production of inflammation-related cytokines. Finally, IL1R2 transcription was significantly lower in patients that relapsed during a 1-year follow-up period compared with those in endoscopic remission. Collectively, our results reveal that the IL-1/IL-1R2 axis is differentially regulated in the remitting intestinal mucosa of UC patients. We hypothesize that IL-1R2 in the presence of low concentrations of IL-1ß may act locally as a regulator of intestinal homeostasis.

[Dental injuries due to miniplate osteosynthesis. Classification, treatment management, complications, and prognosis]. / Zahnverletzungen bei Miniplattenosteosynthese. Einteilung, Therapiemanagement, Komplikationen und Prognose.

BACKGROUND: In spite of a monocortical design, miniplate osteosynthesis can injure dental roots directly as well as damage dental substance indirectly by interrupting the apical blood stream. PURPOSE: The present retrospective study classifies different types of dental root trauma caused by monocortical screws, suggests therapeutic options based on diagnosis, and documents survival probability and prognosis after tooth trauma. PATIENTS AND METHODS: During a period of 11 years, 380 patients with permanent dentition underwent miniplate osteosynthesis for the treatment of mandibular fractures, 29 of whom sustained dental root trauma caused by drilling failure. These patients were clinically and radiographically examined for a follow-up time of not less than 38 months. RESULTS: The 29 patients could be classified into four different types of dental root trauma: 13 pulp injuries above the apical third of the root (type Ia), 6 pulp injuries in the apical third of the root or extradental lesions interrupting the apical blood stream (type Ib), 4 lesions to the central radicular dentin without pulp injury (type II), and 6 lesions to the peripheral radicular dentin and root cementum (type III). Of 13 type Ia injuries, 5 developed apical periodontitis and dilatation of the periodontal space. Therefore one root canal treatment and three apicoectomies were performed. One tooth had to be extracted. Three further type Ia injuries and two type Ib injuries showed root resorptions inducing two root canal treatments. One of six type Ib injuries required root canal treatment because of apical periodontitis. One of four type II injuries caused root resorption not requiring therapy. No relevant, pathological finding could be identified after type III injury. CONCLUSIONS: The type of dental root trauma caused by miniplate osteosynthesis determines therapy, complication rate, and survival of the injured tooth.

[Metallic condylar head prostheses to replace the temporomandibular joint]. / Metallische Halbendoprothesen zum Ersatz des Kiefergelenkkopfes. Vergleich funktioneller und ästhetischer Langzeitergebnisse mit und ohne Rekonstruktion.

BACKGROUND: Up to now the results after condylar reconstruction of the mandible have been regarded as less than satisfactory. PURPOSE: Functional and aesthetic long-term results after condylar head resection in traumatic and tumour cases with or without replacement by a metallic condylar head prosthesis were compared in a retrospective study. PATIENTS AND METHODS: From 1980 to 2001, 23 temporomandibular joints of 19 patients were reconstructed with metallic condylar head prostheses. The resected region, the contralateral joint, facial and masticatory muscles and the dental system were clinically and radiographically monitored for a mean period of 4 years and 9 months. Seven patients who underwent condylar resection without substitution were observed over an average follow-up time of 7 years and 11 months. RESULTS: Patients who underwent condylar resection without substitution reported more trouble with eating and speaking for a long time. TMJ endoprostheses preserved facial symmetry better. Maximum mandibular opening as well as lateral and protrusive excursions were slightly reduced in comparison with both unaffected controls and patients who underwent condylar resection without substitution. In this study bilateral condylar prostheses exhibited the same functional and aesthetic results as unilateral arthroplasty. CONCLUSIONS: Metallic condylar head prostheses originally developed for temporary replacement worked in some cases as long-term joint replacement but were not able to reach the total functional quality of natural temporomandibular joints.

Effect of platelet concentration in platelet-rich plasma on peri-implant bone regeneration.

This study analyzed the effect of the platelet count in platelet-rich plasma (PRP) on bone regeneration in vivo. Twenty male New Zealand white rabbits were used. PRP was produced using the Platelet Concentrate Collection System (PCCS) (3i, Miami, FL, USA). After inducing ketamine-xylazine anaesthesia, a self-tapping titanium screw (Branemark MK III TiUnite, 3.75 x 7 mm) was inserted in each distal femur; the femurs were randomized so that one side was treated with PRP while the other (control) was not. Intravital fluorochrome staining was performed on days 1, 7 (1.5 ml of 2% doxycycline/kg bodyweight), 14 (6% xylenol orange, 1.5 ml/kg), and 21 (1% calcein green, 5 ml/kg). Animals were euthanized on day 28 (n = 20). Specimens were prepared for histomorphological evaluation according to Donath and Breuner [J. Oral Pathol. 11 (1982) 318]. Comparing the bone regeneration (fluorochrome staining) in the 4-week implants (n = 19), the only significant difference (sign test, P = 0.004) was seen with intermediate platelet concentrations (n = 9,503,000-1,729,000 platelets/microl PRP). There were no differences in the bone/implant contact rates between the test and the control side among the three groups. The platelet concentration required for a positive PRP effect on bone regeneration seems to span a very limited range. Advantageous biological effects seem to occur when PRP with a platelet concentration of approximately 1,000,000/microl is used. At lower concentrations, the effect is suboptimal, while higher concentrations might have a paradoxically inhibitory effect. On the other hand, the effect of this type of platelet concentrate was not beneficial to accelerate the osseointegration of enosseous dental implants.

Verification of caries inhibition by a tartar control toothpaste.

OBJECTIVE: The anticaries properties of a silica-based, sodium fluoride (NaF) toothpaste containing tetrapotassium pyrophosphate (PPi) with anti-tartar properties (Aquafresh All Tartar Control) were assessed in specific pathogen-free Osborne-Mendel rats. METHODOLOGY: The dentifrice was compared to a silica-based, fluoride-free control toothpaste that contained PPi but no NaF, termed a "Placebo" (negative control), and a NaF-containing silica-based USP reference standard toothpaste which was used as a positive fluoride control toothpaste. Sixty weanling rats were randomly distributed into groups of 20; all were inoculated with S. mutans 10449S, ate cariogenic diet 2000, and drank demineralized water, ad libitum. Each toothpaste, contained in coded tubes, was applied to the dentitions of rats' teeth for one minute, twice daily on weekdays and once daily on weekends and holidays. There was no difference in weight gains or in recoveries of the S. mutans inoculant from tooth swabs among the groups at either the 24- or 38-day post-inoculation recovery date. After euthanasia at 42 days and defleshing, heads were randomly coded and scored blindly for carious lesions according to Keyes/Larson methods. Only after scoring was completed were the random codes broken to enable statistical analyses. Only after statistical analyses were completed and the data reported to sponsor were the identities of the test items revealed. RESULTS: Both the NaF/PPi-containing and the NaF-containing USP standard toothpaste groups had lower total enamel caries scores (29.8 to 30.6%, respectively) than the group treated with the fluoride-free PPi-containing control. Similar-dimensioned differences were evident both at smooth surface and sulcal enamel sites and in dentinal sites. All were statistically significant at p < 0.001. There were no statistically significant differences at any tooth surface category site between the two fluoride-containing toothpastes' effects. CONCLUSION: It is thus apparent that Aquafresh All Tartar Control, an anti-tartar NaF toothpaste, retains the anticaries benefit of a USP reference standard NaF toothpaste in vivo.

[Adenomatoid odontogenic tumor in calcifying odontogenic cyst]. / Adenomatoider odontogener Tumor in kalzifizierender odontogener Zyste.

BACKGROUND: Adenomatoid odontogenic tumors (AOT) and calcifying odontogenic cysts (COC, Gorlin's cyst) are rare benign specificities of odontogenic tumors. Most odontogenic tumors are lesions of embryonic odontogenic tissue. Radiographically, odontogenic tumors may mimic an odontogenic follicular cyst. CASE REPORT: This paper describes the case of an 11-year-old female patient with a remarkable combination of these two entities. The lesions were found at the site of a retained first premolar and a persistent deciduous tooth 84 of the right lower jaw. Without clinical symptoms the tumor had expanded the vestibular cortical bone of the premolar region. Radiographically, the lesion appeared as a typical follicular cyst. During the operation, excochleation of the cyst was performed and the premolar was extracted. Finally, the epithelium of the cyst was treated by curettage. The histologic specimen revealed the diagnosis of an adenomatoid odontogenic tumor (AOT) in a calcifying odontogenic cyst (COC). DISCUSSION: The described case shows that symptoms of odontogenic tumors are usually nonspecific. For that reason one should always take a biopsy for histological investigation when patients present atypical cysts of the jaw. In rare cases even malignant odontogenic neoplasms could occur.

[Partsch's chronic granulomatous inflammation, the cutaneous manifestation of a dental cause]. / Chronisch granulierende Entzündung nach Partsch. Chirurgisches Problem dentogener Ursache.

Dentogenous inflammatory diseases can lead to typical dermatological facial symptoms with formation of cutaneous sinuses. Partsch's chronic granulomatous inflammation can result from conducted inflammation of a nonvital tooth via a chronic apical inflammation. In this rare disease, the granulomatous tissue perforates the bone, channels through the overlying skin, and drains via cutaneous or oral sinuses. A frequent localization of the cutaneous sinus is the skin inferior to the body of the mandible, and it is caused by an inflammation of the lower molars. Treatment consists of identifying the responsible teeth and eliminating the focus of infection. Chronically progressive periradicular granuloma and/or radicular cysts can be present with impressive dermatological symptoms. Therefore, X-ray examinations are necessary to exclude possible dentogenic causes in cases of badly healing processes of the face or neck.

[Acute tongue necrosis provoked by epirubicin-cyclophosphamide treatment for invasive ductal breast cancer]. / Akute Nekrose der Zunge unter Epirubicin-Cyclophosphamid-Therapie bei einem invasiv duktalen Mammakarzinom.

CASE: Unilateral necrosis of the tongue is an uncommon symptom of different rare diseases. Previously, it had only been described as an infrequent complication of temporal arteritis or as a side effect of therapy with ergotamine. We present a case of unilateral necrosis of the tongue in a 62-year-old woman with invasive ductal carcinoma of the breast treated with epirubicin and cyclophosphamide. RESULTS: The necrosis led to a rapid swelling of the tongue and consequently to an airway obstruction necessitating a tracheotomy. After excision of the necrosis, the swelling of the tongue and the airway obstruction subsided. DISCUSSION: Because of the temporal connection between the occurrence of the necrosis and the administration of chemotherapy, an adverse effect of the administered drugs seems most likely. However, a paraneoplastic pathogenesis cannot be completely excluded. The occurrence of unilateral necrosis of the tongue is a rare complication of the above-mentioned conditions. However, it is important to be aware of the different causes leading to this rare disease in order to initiate the right therapy.

[Criteria of success in implantology]. / Erfolgskriterien in der Implantologie.

BACKGROUND: So far there is no generally accepted definition of success in the case of dental implants, although criteria differing from country to country have been proposed, which evaluate the success of implants with reference to clinical and X-ray control parameters. The aim of the study was to examine the five most frequently used sets of criteria suggested for determination of the success or otherwise of implants ( Albrektsson, Jahn, Buser, NIH conference, Naert) and ascertain their relative values. METHODS: In a clinical review, 508 implants (Astra, Frialit-2, IMZ TwinPlus and ITI) were examined and a subjective evaluation of them was made by the patients. Subsequently a statistical analysis was executed (in situ rate, Kaplan-Meier, success criteria). RESULTS: The average observation time of all implants included in the study was 3.5 years, and the in situ survival rate was 95%; Kaplan-Meier survival analysis revealed that the probability of survival after 6 years was 93%. Application of different criteria for success gave very different results (Albrektsson 88%, Naert 89%, NIH 85%, Buser 88%, Jahn and dacute;Hoedt 75%). DISCUSSION: The increasing importance of quality assurance in medicine makes it necessary to establish standards that will permit reliable comparative analysis of how successful implants are in the future.

[Patient satisfaction with dental implants]. / Patientenzufriedenheit in der Implantologie.

BACKGROUND: Almost all implant systems available today achieve success rates of over 90%. The subjective satisfaction of patients with dental implants is only rarely considered in the definition of implant success and there are only limited data on the satisfaction of patients with dental implants in the literature. Therefore, a satisfaction analysis was carried out in a retrospective study. DESIGN OF STUDY: In addition to a clinical investigation, 330 patients with 1,273 implants (Astra, Frialit-2, IMZ TwinPlus and ITI) were asked to answer a standardized questionnaire to rate their personal opinion on the implant success. A total of 199 questionnaires (803 implants, 63%) were returned and could be analyzed. RESULTS: Of the patients, 67% participated in regular follow-up after implantation and 15% indicated postoperative discomfort. Patient satisfaction with the implants (rated on a scale of 1-6) was good or excellent (2 and 1, respectively) in 88% of cases. Satisfaction with the prosthetic treatment was 80%. The whole treatment was considered good or very comfortable by 86% of patients. If necessary, 91% of patients who underwent the procedure would do so again, and 94% would recommend the procedure to someone else. The Spearman correlation analysis did not reveal any statistically significant correlations between the clinical parameters and patient satisfaction scores. DISCUSSION: Despite the high number of patients involved ( n=330), the expected influence of objective clinical parameters on patient satisfaction could not be statistically evaluated. Nevertheless, in addition to the clinical parameters, subjective patient satisfaction should be included in the evaluation of implant success.

[Acral ischemia as a rare paraneoplastic syndrome in the terminal phase of mouth floor carcinoma]. / Akrale Ischämie als seltene Paraneoplasie in der terminalen Erkrankungsphase eines Mundbodenkarzinoms.

BACKGROUND: The term "paraneoplastic syndrome" describes a clinically apparent disease associated with a malignant neoplasm, which is not a direct consequence of invasive tumor growth. Acral ischemia and digital necrosis of multiple fingertips have been occasionally described as a paraneoplastic syndrome. However, the exact mechanisms of this phenomenon are still not adequately known. CASE REPORT: This paper describes a 72-year-old male patient with severe acral ischemia and multiple necroses on several fingertips. Symptoms evolved under palliative chemotherapy with gemcitabine for inoperable metachronous squamous cell carcinoma of the tonsil following a history of two simultaneous carcinomas of the alveolar crest. Digital ischemia was combined with severe pain, similar to Raynaud's syndrome, which required therapeutic intervention. The treatment objective is to improve perfusion and simultaneously reduce pain. A combination of iloprost, an analog of prostacyclin (50 micrograms intravenous Ilomedin once daily), and a CT-guided thoracic sympathectomy achieved a continuous positive effect on the intensity of acral ischemia and alleviated the pain.

A novel pharmacological probe links the amiloride-insensitive NaCl, KCl, and NH(4)Cl chorda tympani taste responses.

Chorda tympani taste nerve responses to NaCl can be dissected pharmacologically into amiloride-sensitive and -insensitive components. It is now established that the amiloride-sensitive, epithelial sodium channel acts as a sodium-specific ion detector in taste receptor cells (TRCs). Much less is known regarding the cellular origin of the amiloride-insensitive component, but its anion dependence indicates an important role for paracellular shunts in the determination of its magnitude. However, this has not precluded the possibility that undetected apical membrane ion pathways in TRCs may also contribute to its origin. Progress toward making such a determination has suffered from lack of a pharmacological probe for an apical amiloride-insensitive taste pathway. We present data here showing that, depending on the concentration used, cetylpyridinium chloride (CPC) can either enhance or inhibit the amiloride-insensitive response to NaCl. The CPC concentration giving maximal enhancement was 250 microM. At 2 mM, CPC inhibited the entire amiloride-insensitive part of the NaCl response. The NaCl response is, therefore, composed entirely of amiloride- and CPC-sensitive components. The magnitude of the maximally enhanced CPC-sensitive component varied with the NaCl concentration and was half-maximal at [NaCl] = 62 +/- 11 (SE) mM. This was significantly less than the corresponding parameter for the amiloride-sensitive component (268 +/- 71 mM). CPC had similar effects on KCl and NH(4)Cl responses except that in these cases, after inhibition with 2 mM CPC, a significant CPC-insensitive response remained. CPC (2 mM) inhibited intracellular acidification of TRCs due to apically presented NH(4)Cl, suggesting that CPC acts on an apical membrane nonselective cation pathway.

Caries inhibition in rats by a sodium fluoride, tripolyphosphate toothpaste with whitening and anti-tartar properties.

The anti-caries properties of a silica-based, sodium fluoride (NaF) toothpaste containing sodium tripolyphosphate (NaTPP) with tooth whitening and anti-tartar properties (Aquafresh Whitening), in specific pathogen-free Osborne-Mendel rats, were assessed in this study. A silica-based, fluoride-free placebo containing NaTPP, and a NaF-containing silica-based USP reference standard toothpaste were used as negative and positive control toothpastes, respectively. Sixty weanling rats were randomly distributed into groups of 20; all were inoculated with S. mutans 10449S, ate cariogenic diet 2000, and drank demineralized water ad libitum. Each toothpaste, packaged in coded tubes, was applied to the dentitions of the rats' teeth for one minute, twice daily on weekdays, and once daily on weekends and holidays. Both the NaF/NaTPP-containing and the NaF-containing USP standard toothpaste groups had lower total enamel caries scores (41 to 45%) than the group treated with the fluoride-free NaTPP-containing placebo. Similar dimensioned differences were evident both at smooth surface and sulcal enamel sites, and in dentinal sites. All were statistically significant at p < 0.001. There were no statistically significant differences at any tooth surface category site between the two fluoride-containing toothpastes' effects. It is thus apparent that Aquafresh Whitening has the anticaries benefit of a USP reference standard NaF toothpaste.

Five-year prospective follow-up report of the Astra tech standard dental implant in clinical treatment.

Between 1994 and 1999, 515 Astra standard implants were placed and documented prospectively in 107 patients. Of these implants, 364 were placed in original jawbone, 38 in areas augmented with local osteoplasty, and 113 in bone grafts from the iliac crest. The main indications for implantation were an atrophic edentulous alveolar crest (n = 361) and a shortened dental arch (n = 113). Single-tooth implants were excluded. In a special clinical examination, 56 patients with 258 implants were investigated. The average in situ time of the implants was 34.2 months. Failing osseointegration (n = 10), peri-implantitis (n = 10), and implant fracture (n = 1) in 15 patients resulted in the failure of 21 implants (4.1%). Three patients with 8 implants died from malignant tumor. Currently, 27 implants have been lost to follow-up, and 488 implants remain in situ (95.9%). Under analyses with different implant success criteria, the success rate decreased to 85%. Based on the results in this patient population, this implant was found to be a useful alternative to established implant systems for the indications analyzed.

[IMZ-TwinPlus bone implant system--4 years clinical experience]. / Das IMZ-TwinPlus-Schraubenimplantat-System--4 Jahre klinische Erfahrung.

AIM OF THE STUDY: For more than twenty years the IMZ-system has been in clinical use, since 1995 modified as IMZ-TwinPlus. The aim of this prospective clinical trial was to analyse the success of the latter implant system, which is an automatically threading cylindrical titanium screw with a deep structured surface (Fa. FRIATEC AG, Mannheim, BRD). Investigated parameters were the peri-implant situation of the soft tissues, the bone loss and the rate of implant failure after a maximum period of 4.5 years of clinical use. MATERIAL AND METHODS: From 1995-2000 sixty-eight patients were provided with a total of 278 IMZ TwinPlus screw implants for various indications (mainly alveolar ridge atrophy). 191 implants were inserted without any, 35 implants with a loco-regional and another 52 implants after comprehensive reconstructive osteoplastic surgery. 38 patients with 155 implants were re-examined using a standardised protocol to evaluate peri-implant hard- and soft tissue situation as well as the patient's subjective assessment of the treatment. RESULTS: With a maximum of 54 months the mean observation period was 30 months. The implant failure rate has risen to 6% so far (n = 18 in 12 patients). Two patients bearing 7 implants have passed away. One patient with 4 implants was lost to follow up. 249 implants were still under function at examination, thus the in situ rate was 91%. The Kaplan-Meier survival rate after 54 months proved 91%. DISCUSSION: To our knowledge there are at present no other data published on the survival rate of the IMZ TwinPlus implant system. The results of this study evaluate a survival rate similar to the classical IMZ cylinder implant and other implant systems for the analysed observation period. CONCLUSIONS: After a maximum observation period of 4.5 years the IMZ TwinPlus implant system showed results in the range of other well-established implant systems. Designed to resist rotation of the superstructure the IMZ TwinPlus screw implant widens the range of indications in comparison to the classical IMZ cylinder implant system.

Cryosurgery in the treatment of giant cell tumor. A long-term followup study.

Between 1983 and 1993, 102 patients with giant cell tumor of bone were treated at three institutions. Sixteen patients (15.9%) presented with already having had local recurrence. All patients were treated with thorough curettage of the tumor, burr drilling of the tumor inner walls, and cryotherapy by direct pour technique using liquid nitrogen. The average followup was 6.5 years (range, 4-15 years). The rate of local recurrence in the 86 patients treated primarily with cryosurgery was 2.3% (two patients), and the overall recurrence rate was 7.9% (eight patients). Six of these patients were cured by cryosurgery and two underwent resection. Overall, 100 of 102 patients were cured with cryosurgery. Complications associated with cryosurgery included six (5.9%) pathologic fractures, three (2.9%) cases of partial skin necrosis, and two (1.9%) significant degenerative changes. Overall function was good to excellent in 94 patients (92.2%), moderate in seven patients (6.9%), and poor in one patient (0.9%). Cryosurgery has the advantages of joint preservation, excellent functional outcome, and low recurrence rate when compared with other joint preservation procedures. For these reasons, it is recommended as an adjuvant to curettage for most giant cell tumors of bone.

Reconstruction using the saddle prosthesis following excision of primary and metastatic periacetabular tumors.

From 1988 to 1991, 17 patients with malignant periacetabular tumors underwent limb-sparing surgery and reconstruction using the saddle prosthesis. There were 8 patients with primary malignant lesions (Group 1), and 9 patients with metastatic or systemic tumor involving the periacetabular pelvis (Group 2). All resections included excision of the acetabulum. Patients ranged in age from 24 to 76 years (average, 59.8 years). Local control was achieved in all patients. Wide margins were obtained in all patients with primary pelvic tumors. Functional outcomes were rated as follows excellent (10), good (2), fair (1), and poor (4). Three patients, all of whom had pulmonary metastasis before surgery, died within 8 months of surgery. Of the remaining 14 patients, 5 patients died between 6 and 28 months after the index procedure. At the end of the followup period, 9 patients were still alive (6 in Group 1 and 3 in Group 2), with a followup period ranging from 15 to 62 months (average, 33.4 months). The overall results for surviving patients were 7 excellent and 2 good results, with no fair or poor results.