Implant reconstruction of the jaws and craniofacial skeleton

Full oral rehabilitation with a high degree of success is now possible with osseointegrated implants. Osseointegration is a direct connection between living bone and the titanium implant at the level of the light microscope. Osseointegrated implants are currently used to replace single teeth, support fixed bridges and stabilize full dentures. These implants can also be placed extraorally for attachment of facial prosthesis. The surgical technique used to place implants intraorally into jaws or facial skeleton is performed in two stages using a local anesthetic and/or conscious sedation. During stage I surgery, holes are placed into the jaw using a series of gradually larger diameter burs until the desired diameter and depth of the bony preparation is achieved. The implant is then placed. The implant must remain undisturbed for 4 months for osseointegration to take place. Stage II surgery is then required to remove the mucosa over the implant and place the transmucosal abutment. After 1-2 weeks of healing, the restorative dentist can take an impression and fabricate the prosthesis. On occasion, it is necessary to augment the height and width of the atrophic jaw with autogenous or allogeneic bone grafts prior to implant placement. Bone grafts are sometimes placed on the floor of the nose or the floor of the maxillary sinus. Guided tissue regeneration is a technique used to generate bone within bony defects adjacent to implants. With long-term rates of success (5 years) of 99% for implants placed in the mandible and 95% for those placed in the maxilla, reconstruction of the jaws and cranial facial skeleton with osseointegrated implants has become the treatment of choice.     

Cholesterol 7 alpha-hydroxylase activity in hypothyroidism and hyperthyroidism in humans

The effects of three root-end filling materials on healing following endodontic surgery were assessed radiologically and correlated with histological findings reported elsewhere. The materials compared were a light-cured glass ionomer cement (Vitrebond), a reinforced zinc oxide-eugenol cement (Kalzinol) and amalgam. The root canals of 27 two-rooted mandibular premolar teeth of six beagle dogs were inoculated with endodontic pathogenic bacteria to induce periradicular lesions. The roots were apicected and root-end cavities filled with the tested filling materials. The teeth and surrounding jaw were removed after 4 weeks (30 roots) or 8 weeks (24 roots). Radiographs were taken of each jaw section and subjected to image analysis. Healing was evaluated based on measurements of the size of the periradicular radiolucent areas. ANOVA disclosed no statistically significant differences in the size of the periradicular areas either between time periods or between materials. These results did not correlate with the tissue responses in the same material as assessed histologically and previously reported. The use of radiographs alone to assess healing after endodontic surgery in the dog mandible is unsatisfactory, and should not be regarded as a substitute for histological examination for the determination of healing.     

The reliability of apical x-ray pictures in the diagnosis of mandibular bone lesions. A review of the literature and in-vitro study

Using 6 macerated human anatomical preparations of mandibular jaw regions with either front teeth or premolars and molars, the radiological detectability of artificial periapical bone lesions was evaluated in relation to the size of the lesions and to the angle of x-ray projection. The artificial lesions were enlarged stepwise until distinct radiological visibility was attained. For each step of enlargement, x-ray pictures were taken with orthoradial as well as with at 25 degrees mesially and distally excentered projections. All x-ray pictures were evaluated by 6 dentists. The following results were obtained: The size of a periapical bone lesion, at which it is becoming radiologically detectable, varies between the different regions of the lower jaw. Isolated spongiosa lesions being larger than 3 mm in diameter are most often detectable at mandibular front teeth and premolars. Isolated spongiosa lesions at mandibular molars are generally non-detectable. Atypical lesions, e.g. discontinuities of bony structures are particularly difficult to detect radiologically. There were no statistically significant differences in lesion detectability between x-rays of different angle projections.     

Lateral displacement of the mandible in Rhesus monkeys

Lateral displacement of the mandible was induced experimentally in five adult male Rhesus monkeys. Following from 2 1/2 weeks to 19 months, the animals were sacrificed and examined histologically. Two of the monkeys received H3 proline 4 months prior to sacrifice and radioautographs were prepared. The lateral displacement apparently caused great discomfort because the monkeys refused to eat and lost weight rapidly for a few months. After about 12 months, the monkeys could again eat their normal diet to the extent they started to gain weight slowly. The histological and radio-autographic findings indicated almost no changes of the articular surfaces of the temporomandibular joints. However, extensive reorganization of the neck of the condyles was observed. Severe periodontal trauma and extensive movements of the teeth occurred in spite of the fact that the teeth in each jaw were splinted firmly together.     

Diagnosis of infra-alveolar bony lesions in the dentate alveolar process with high-resolution computed tomography. Experimental results

RATIONALE AND OBJECTIVES: Conventional intraoral radiography was compared with axial computed tomography (CT) scans for identification and classification of bony pockets in dentate jaw segments. METHODS: Fifty-five artificial bone defects were produced in six dentate jaw segments. The jaws were examined radiographically using a dental x-ray unit and by contiguous axial CT scans. Identification, classification, and vertical depth of the bony defects were compared among the specimens, radiographs, and CT scans. RESULTS: On the intraoral radiographs, 38 (69%) bony lesions were identified, and the vertical depth was underestimated by a mean of 2.2 mm, compared with the objective measurements on the jaws. In contrast, all artificial bony lesions (100%) were identified and classified on the axial CT scans and the vertical depth was underestimated by a mean of 0.5 mm. CONCLUSIONS: High-resolution CT improves the identification and metric assessment of the vertical dimension of infra-alveolar bony lesions compared with conventional intraoral x-ray films and allows these defects to be classified according to the number of existing walls into one-walled, two-walled, and three-walled bony pockets. In patients with apically extended metallic restorations, the image quality could be limited by artifacts.     

Isolation, inoculation to insect host, and molecular phylogeny of an entomogenous fungus Paecilomyces tenuipes

BACKGROUND: To improve the poor prognosis of patients with advanced incurable gastric cancer, intensive chemotherapy combined with radical surgery was used. PATIENTS AND METHODS: Thirty patients with incurable gastric cancer were treated with a combination of 5-fluorouracil (370 mg/m2) and leucovorin (30 mg/person), given intravenously for five consecutive days, followed by cisplatinum (70 mg/m2) and etoposide (70 mg/m2) on days 6 and 20, delivered through a catheter placed either in the aorta with its tip at the level of the ninth thoracic vertebra or in the celiac artery. This treatment (FLEP therapy) was repeated twice every 5 weeks. Radical or palliative surgery followed chemotherapy. RESULTS: The overall response rate to the chemotherapy was 50.0% (15 of 30 patients, 95% confidence limit 0.305-0.671). Nineteen patients (15 with a partial response, three showing no change, and one with progressive disease) underwent surgery. Of these, nine underwent curative surgery and 10 palliative surgery. The median survival time was 6.5 months overall, 12.7 months for responders, and 4.7 months for nonresponders. Long-term survivors were exclusively found among patients with distant lymph node metastasis treated by curative surgery (55.6% at 5 years). CONCLUSIONS: Favorable results of this small phase II study justify a phase III trial.     

Chemotherapy followed by surgery compared with surgery alone for localized esophageal cancer

BACKGROUND: We performed a multi-institutional randomized trial comparing preoperative chemotherapy followed by surgery with surgery alone for patients with local and operable esophageal cancer. METHODS: Preoperative chemotherapy for patients randomly assigned to the chemotherapy group included three cycles of cisplatin and fluorouracil. Surgery was performed two to four weeks after the completion of the third cycle; patients also received two additional cycles of chemotherapy after the operation. Patients randomly assigned to the immediate-surgery group underwent the same surgical procedure. The main end point was overall survival. RESULTS: Of the 440 eligible patients with adequate data , 213 were assigned to receive preoperative chemotherapy and 227 to undergo immediate surgery. After a median possible study time of 55.4 months, there were no significant differences between the two groups in median survival: 14.9 months for the patients who received preoperative chemotherapy and 16.1 months for those who underwent immediate surgery (P=0.53). At one year, the survival rate was 59 percent for those who received chemotherapy and 60 percent for those who had surgery alone; at two years, survival was 35 percent and 37 percent, respectively. The toxic effects of chemotherapy were tolerable, and the addition of chemotherapy did not appear to increase the morbidity or mortality associated with surgery. There were no differences in survival between patients with squamous-cell carcinoma and those with adenocarcinoma. Weight loss was a significant predictor of poor outcome (P=0.03). With the addition of chemotherapy, there was no change in the rate of recurrence at locoregional or distant sites. CONCLUSIONS: Preoperative chemotherapy with a combination of cisplatin and fluorouracil did not improve overall survival among patients with epidermoid cancer or adenocarcinoma of the esophagus.     

Reproducibility of transvaginal Doppler velocimetry measurements in the uterine arteries of postmenopausal women

Thirty cases of osteosarcoma of the jaws were reviewed (20 men and 10 women, mean age 34 years). Seventeen lesions occurred in the mandible and 13 in the maxilla. Swelling without pain was the most common presenting symptom. Thirteen lesions were initially misdiagnosed as odontogenic infections. Numbness as a presenting symptom was statistically associated with poor prognosis. Treatment included all combinations of surgery, chemotherapy and radiotherapy. Patients receiving chemotherapy with four or more agents showed a trend toward better survival with 71% alive and disease-free at the time of review. Patients' increasing age was statistically associated with decreased survival. The average age of survivors was 27 years and nonsurvivors, 40 years. Older patients suffered more local recurrences which, in all but one case, resulted in mortality. Expectedly, clear surgical margins correlated statistically with improved survival. With margins of less than 5 mm, 27% of patients were alive and disease-free as compared to 62% with surgical margins greater than 5 mm. The importance of early diagnosis, definitive surgical treatment and aggressive adjuvant chemotherapy is demonstrated. The Proportional Hazards Regression model was employed to evaluate the statistical significance of a variety of factors on disease-free and overall survival.     

Fibula osteoseptocutaneous flap for reconstruction of osteoradionecrosis of the mandible

Osteoradionecrosis of the mandible poses formidable problems for treatment. In the last 6 years, the fibula osteoseptocutaneous free flap was used in 12 cases to replace mandibles with radionecrotic damage. The presence of a pathologic fracture, exposed necrotic bone, or a persistent fistula not responding to conservative treatment were the indications for such a radical approach. Mandible defects after resection were around 8.0 cm long, and in all cases intraoral mucosa, skin, or both were included with the bone excision. All vascularized fibula osteoseptocutaneous flaps transplanted were successful with good primary bone healing. Adequate facial symmetry and improvement in oral function was achieved. No evidence of osteoradionecrosis recurrence was observed after a mean follow-up period of 3 years and 9 months. The advantages of using the fibula osteoseptocutaneous flap for mandible reconstruction are numerous, and good aesthetic and functional results can be obtained when it is used for reconstruction after radical excision of osteoradionecrotic lesions.     

A therapeutic approach to childhood pelvic rhabdomyosarcoma without pelvic exenteration

A therapeutic approach using chemotherapy rather than radical surgery as the initial modality of treatment was employed in 13 children with pelvic rhabdomyosarcoma. One patient failed to respond to chemotherapy and required anterior pelvic exenteration. Eight patients are alive and free of disease 24 to 96 months after diagnosis. Limited surgery for minimal residual disease was used in two patients. Radiation therapy at lower than conventional doses was used in seven of eight patients. This experience supports a therapeutic approach to childhood pelvic rhabdomyosarcoma with an initial chemotherapy regimen, resulting in the use of surgical procedures less detrimental to pelvic organs without compromising survival.     

Neoadjuvant chemotherapy and bladder-sparing surgery for invasive bladder cancer: ten-year outcome

PURPOSE: To evaluate the 10-year outcome of patients with invasive (T2-3N0M0, staged according to the tumor, node, metastasis system) bladder cancer who responded completely to a combination of methotrexate, vinblastine, adriamycin, and cisplatin (MVAC) chemotherapy followed by bladder-sparing surgery. PATIENTS AND METHODS: Of 111 surgical candidates who received neoadjuvant MVAC, 60 (54%) achieved a complete clinical response (T0) on transurethral resection (TUR) of the primary tumor site. Of these, 28 requested follow-up with TUR alone, 15 had a partial cystectomy, and 17 elected a radical cystectomy. The patients were followed up for a median of 10 years (range, 8 to 13 years). RESULTS: Of 43 patients who had bladder-sparing surgery, 32 (74%) are alive, which includes 25 (58%) with an intact functioning bladder. Twenty-four patients (56%) developed bladder tumor recurrences from 5 to 96 months, which were invasive in 13 (30%) and superficial in 11 (26%). Thirteen patients required a salvage cystectomy, of whom 6 died, which includes 4 (9%) from a new invasive neoplasm. Of the 17 patients who had radical cystectomy, 11 (65%) are alive. CONCLUSION: The majority of patients with invasive bladder tumors who achieve T0 status after neoadjuvant MVAC chemotherapy preserve their bladders for up to 10 years with bladder-sparing surgery. The bladder remains at risk for new invasive tumors. Cystectomy salvages the majority, but not all, of relapsing patients.     

Prediction of mandibular autorotation

PURPOSE: The purpose of this investigation was to test the hypothesis that the mandible rotates around the same point during maxillary impaction surgery as during initial jaw opening. This point, called the center of mandibular autorotation (CAR), could then be used to predict mandibular position and to decide whether only maxillary impaction would be needed to correct the occlusion and the facial profile. PATIENTS AND METHODS: Preoperatively, two lateral cephalograms were obtained from a consecutive series of 20 patients who underwent maxillary impaction without concomitant mandibular ramus osteotomy. One cephalogram was taken with the mandible in centric relation using a wax bite wafer and another with a jaw opening of 10 mm using a fabricated acrylic bite block with the mandible manipulated to its most retruded position. The CAR was calculated before and after jaw opening using the Rouleaux method on the lower incisor and gonion point. A third lateral cephalogram was taken within 2 days postoperatively. The postoperative lower incisal point was then transferred to the first cephalogram using cranial base superimposition. RESULTS: When the preoperative and postoperative distances between CAR and incisal point were compared, there was no significant difference between these distances, proving the hypothesis. CONCLUSIONS: The method used is a practical and precise way to determine the center of mandibular autorotation on an individual basis. The center of rotation during initial jaw opening is the same as during impaction surgery.     

Modified type IV-V radical hysterectomy with systematic pelvic and aortic lymphadenectomy in the treatment of patients with stage III cervical carcinoma. Feasibility, technique, and clinical results

BACKGROUND: Due to the high prevalence of perioperative major morbidity and the difficulties in achieving surgical disease free margins, surgery has had no role in the treatment of patients with Stage III cervical carcinoma. METHODS: Forty-two women with International Federation of Gynecology and Obstetrics (FIGO) Stage III cervical carcinoma responding to platinum-based neoadjuvant chemotherapy underwent the maximum surgical effort, comprised of a modified type IV-V radical hysterectomy (37 patients) or anterior pelvectomy (5 patients) with systematic pelvic and aortic lymphadenectomy. Feasibility, modifications of surgical technique, and pathologic and clinical data were analyzed. RESULTS: Surgery was feasible in all 42 patients intraoperatively selected. Disease free margins were achieved in all but one patient. The median operating time was 390 minutes, and the median estimated blood loss was 800 mL. In the last series of patients, these figures declined to 320 minutes and 600 mL, respectively. Major morbidity consisted of severe intraoperative hemorrhage in two patients, pulmonary embolism in four, ureteral fistula in three, and laparocele in three. The number of lymph nodes removed ranged from 30 to 117 with a median of 56. The mean lengths of vagina and lateral parametrium resected were 55 and 48 mm, respectively. Despite perioperative chemotherapy, lymph node metastasis was present in 36% of patients, parametrial disease in 38%, and vaginal disease in 45%. After a median follow-up of 53 months, the 5-year overall and disease-free survival rates of radically operated patients were 70% and 58%, respectively. CONCLUSIONS: Thanks to improved surgical technique and perioperative care, extended radical surgery appears to be feasible with acceptable morbidity in chemosensitive women with Stage III cervical carcinoma and may constitute a valid alternative to radiotherapy in these patients.     

Selective bladder preservation by combination treatment of invasive bladder cancer

BACKGROUND: For patients with invasive bladder cancer the usual recommended treatment is radical cystectomy, although transurethral resection of the tumor, systemic chemotherapy, and radiotherapy are each effective in some patients. We sought to determine whether these treatments in combination might be as effective as radical cystectomy and thus might allow the bladder to be preserved and the cancer cured. METHODS: We enrolled 53 consecutive patients with muscle-invading bladder cancer (stages T2 through T4, NXM0) in a trial of transurethral surgery, combination chemotherapy, and irradiation (4000 cGy) with concurrent cisplatin administration. Urologic evaluation of the tumor response directed further therapy: radical cystectomy in the 8 patients who had incomplete responses, additional chemotherapy and radiotherapy (6480 cGy) in the 34 patients who had complete responses or who were unsuited for cystectomy, and alternative care in the 11 patients who could not tolerate either irradiation or chemotherapy. RESULTS: After a median follow-up of 48 months, 24 of the 53 patients (45 percent) were alive and free of detectable tumor. In 31 patients (58 percent) the bladder was free of invasive tumor and functioning well, even though in 9 (17 percent) a superficial tumor recurred and required further transurethral surgery and intravesical drug therapy. Of the 28 patients who had complete responses after initial treatment, 89 percent had functioning tumor-free bladders. CONCLUSIONS: Conservative combination treatment may be an acceptable alternative to immediate cystectomy in selected patients with bladder cancer, although a randomized clinical trial that included a group for simultaneous comparison would be required to produce definitive results.     

Pharmacokinetics of CDDP by the route of administration in patients with ovarian cancer

Seventy patients with local squamous cell carcinoma of the esophagus were treated between 1981 and 1990 with preoperative chemotherapy, surgical resection, and possible postoperative radiation therapy and/or chemotherapy. Chemotherapy included two cycles of 5-fluorouracil (1000 mg/m2) by continuous intravenous infusion on days 1-4 and cisplatin (100 mg/m2) on day 4. Complete clinical response (CCR) was achieved in 28 (41%) patients, partial clinical response (PCR) in 17 (25%), and no response in 23 (34%). Fifty-five (81%) patients were resected, 6 (9%) were explored, and 7 (10%) were unable to have surgery. Microscopic analysis of 55 resected patients showed 50 (91%) with active tumor, 1 (2%) with necrotic tumor, and 4 (7%) with a pathological complete response to chemotherapy. Twenty-six of the 55 resected patients (47%) had no gross evidence of disease at the time of surgical inspection. Median overall survival was 21.86 months (range 2-107 months) for all patients and 26.71 months (range 2-107 months) for resected patients. Actuarial 5-year survival rate was 31% for all patients and 39% for resected patients. Prolonged survival correlates with complete clinical response to chemotherapy, low pathological stage of disease, and successful resection of the lesion.     

Treatment of Class II, Division 2 in the late growth period

The "Deckbiss" with skeletal Class II jaw relationship sometimes presents a considerable therapeutic problem, particularly in the late growth period (DP3U), as regards the coordination of dental and skeletal treatment objectives. An effective treatment approach was demonstrated: a modified Herbst appliance used simultaneously with fixed appliances in the maxilla. The sample comprised 12 male (14.0 +/- 0.9 years old) and 10 female (12.3 +/- 0.4 years old) patients. Correction of the distal occlusion was achieved in all patients by means of the Herbst appliance, which was removed after an average time period of 6.4 +/- 0.2 months. In the mandible the multibracket appliances were then immediately inserted, and Class II elastics were used for retention. Maximum anchorage was required in the maxilla as well as in the mandible. Complete diagnostic records were made at the beginning of the treatment as well as 6 and 12 months later, in order to document skeletal and dental changes. A dental and skeletal Class I relationship was achieved in all cases. A significant improvement was recorded in the vertical jaw base relationship; this was still stable after a period of 12 months. In the dental area in particular, a so-called high-pull headgear effect (intrusion and distalization 16, 26) and intrusion of teeth 34, 44 were registered. Only a minor protrusion of the mandibular incisors was observed. Reinforcement of the bands reduced the failure rate significantly. The Herbst appliance does not represent a standard treatment for Class II. Its indication range is limited.     

Genitourinary small cell carcinoma: determination of clinical and therapeutic factors associated with survival

PURPOSE: We assessed the prognostic impact of genitourinary small cell carcinoma tumor and patient characteristics, and therapy. MATERIALS AND METHODS: We retrospectively reviewed the records of 180 patients with genitourinary small cell carcinoma in which patient and tumor characteristics, therapy, followup duration and survival status had been documented. Patient age, sex, primary site, histological features, tumor size, stage, locoregional therapy, systemic chemotherapy and hormonal manipulations were analyzed for association with survival. RESULTS: There were 106 cases of bladder, 60 prostatic, 8 renal and 6 ureteral small cell carcinoma. Median survival was 10.5 months overall, and 7 and 13 months for prostatic and bladder small cell carcinoma, respectively (p <0.0001 log rank analysis). In all cases metastatic disease at presentation (p <0.008, risk ratio 1.9) predicted poor survival on multivariate analysis. Radical surgery (p <0.0001, risk ratio 0.34) and cisplatin chemotherapy (p <0.0001, risk ratio 0.20) were the only factors that predicted improved survival on multivariate analysis. For prostatic small cell carcinoma primary surgical therapy (p <0.012, risk ratio 0.46) was the only parameter that predicted survival on univariate analysis. For bladder small cell carcinoma only cisplatin chemotherapy (p <0.0001, risk ratio 0.15) predicted survival on multivariate analysis. CONCLUSIONS: Genitourinary small cell carcinoma has a poor prognosis, which is worse in prostatic than bladder disease. Patient and tumor characteristics were not determinants of survival when prostatic and bladder small cell carcinoma were analyzed individually. For prostatic disease only primary surgical therapy was associated with prolonged survival, while for bladder disease cisplatin chemotherapy was associated with a favorable prognosis. We recommend considering primary surgical therapy for prostatic and cisplatin based chemotherapy for bladder small cell carcinoma.     

Lung cancer--management and outcome in Glasgow, 1991-92

Current practice and outcome for patients with lung cancer were determined by retrospective case note review of a random sample of all lung cancer cases registered for a calendar year and augmented by review of all surgical and radical radiotherapy cases. A total of 262 patients - 231 patients less than 75 years of age and 31 patients more than 75 years of age - represented 83% of the random sample. Eighty-three per cent of patients were seen within 2 weeks of referral. One-third reported symptoms occurring for less than 1 month and one-third had experienced symptoms for more than 3 months. The median time interval from first hospital contact until the making of a management decision was 18 days. The median interval from first contact to surgery was 63 days, and to starting radical radiotherapy 70 days. Histological confirmation was obtained in 69% of patients. Ten per cent of all lung cancer patients were calculated to have received chemotherapy. Five per cent of the whole cohort had definitive surgery and 64% of these were judged to be free of the disease at 3 years. Overall survival was 9% at 3 years, with no differences relating to cell type or area of residence. Many areas of good practice have been identified, but the lack of tumour staging or performance status data, the low proportion receiving chemotherapy or definitive surgery and the poor outcome after radical radiotherapy indicate the need for prospective audit and feedback of results. The long time interval from management decision to surgery and radiotherapy suggests organizational issues which need attention.     

Solitary necrotic nodules of the liver

An experience is reported with solitary necrotic nodules of the liver, rare benign lesions described for the first time in 1983. Two patients were referred to our department because of the presence of hepatic lesions that radiology showed to be suspected secondary liver tumors. At laparotomy, both patients underwent liver resections because the lesions appeared to be malignant. Subsequent histological examination of the surgical specimens revealed that both were solitary necrotic nodules of the liver. These were the only solitary necrotic nodules found in a total of 840 operations carried out in our department since October 1981. Although they are completely benign, solitary necrotic nodules have a similar ultrasound pattern and radiological features to metastases and have been described in the literature during the follow-up of patients with other tumors. Uncertainty remains as to the etiology of these lesions, which still represent an occasional finding in liver surgery.