Hemimandibulectomy without bone grafting: report of a case.

Some patients require hemimandibulectomy who are poor candidates for reconstructive surgery or who do not want to subject themselves to multiple surgical episodes. With the use of an articulated external skeletal fixation appliance, near-normal esthetics and function can be achieved in these patients without bone grafting. A report of one such case is presented.

Hafnium Germanate from a Hydrous Hafnium Germanium Oxide Gel.

The gel chemistry of germanium is explored through the formation and composition of a hydrous metal oxide precursor gel used in the preparation of the HfGeO(4) and HfGeO(4):Ti X-ray phosphors. The enhanced solubility of hexagonal GeO(2) in dilute ammoniacal solutions is exploited to give a convenient and high-yield precipitation. The precursor gel is shown by FT-IR to be a diphasic mixture of hydrous hafnia and an ammonium germanate gel. Thermal treatment drives the crystallization of a hafnium-rich, simple tetragonal Hf(1)(-)(x)()Ge(x)()O(2) structure at 893 degrees C, that upon further heating to 1200 degrees C yields scheelite HfGeO(4).

The British-Norwegian migrant study: 5-year mortality differentials due to cigarette smoking.

Cigarette smoking and 5-year survivorship of 20,017 British and 10,016 Norwegian migrants to the United States were compared with 17,696 British and 26,155 Norwegian nonmigrants. The highest mortality ratios for 5-year age-adjusted death rates observed were of cigarette smokers to nonsmokers, ranging from 1.40 to 1.60 for men and from 1.18 to 1.36 for women. Mortality ratios of nonmigrants to migrants ranged from 1.07 to 1.19 for men and from 1.22 to 1.36 for women. Mortality ratios for British to Norwegian groups ranged from 1.13 to 1.27. Some differences in mortality ratios for cardiovascular diseases contrasted with mortality ratios for noncardiovascular diseases were noted. The most important of these differences was the apparent lack of any consistent difference between nonmigrants and migrants in their 5-year cardiovascular mortality rates, although there were consistent differences for noncardiovascular diseases.

In vitro retentive strength of fixed bridges constructed with acrylic pontics and an ultraviolet-light-polymerized resin.

The in vitro retentive strength of 24 test bridges was studied. The bridges were maxillary canine to central incisor spans, and an acrylic pontic replaced the lateral incisors. The pontic was retained by a resin polymerized with ultraviolet light. The mean forces necessary to dislodge the pontic bonded to natural teeth in the three-unit bridges were determined to be 41.5 lb for a force applied toward the incisal edge and 55.8 lb for a force applied toward the gingival ridge. A promising clinical application of this technique is suggested.

Skeletal evidence for child abuse: a physical anthropological perspective.

Analysis of the skeletal remains of abused children can prove challenging for forensic pathologists and radiographers who are inexperienced in the direct examination of bones. In such cases, radiographically invisible skeletal lesions that document a history of trauma can often be identified by a physical anthropologist with appropriate osteological experience. This is illustrated by cases in which skeletal remains of four murdered children and a mentally handicapped adult produced evidence of antemortem trauma and perimortem injuries that was critical in developing murder cases against the assailants. In these cases, well-healed areas of subperiosteal new bone formation were identified that were below the threshold of radiographic detection. Such injuries provide strong evidence for a history of physical abuse.

Evidence-based clinical practice guideline for the evaluation of potentially malignant disorders in the oral cavity: a report of the American Dental Association

BACKGROUND: An expert panel convened by the American Dental Association (ADA) Council on Scientific Affairs and the Center for Evidence-Based Dentistry conducted a systematic review and formulated clinical recommendations to inform primary care clinicians about the potential use of adjuncts as triage tools for the evaluation of lesions, including potentially malignant disorders (PMDs), in the oral cavity. TYPES OF STUDIES REVIEWED: This is an update of the ADA's 2010 recommendations on the early diagnosis of PMDs and oral squamous cell carcinoma. The authors conducted a systematic search of the literature in MEDLINE and Embase via Ovid and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials and diagnostic test accuracy studies. The authors used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the certainty in the evidence and to move from the evidence to the decisions. RESULTS: The panel formulated 1 good practice statement and 6 clinical recommendations that concluded that no available adjuncts demonstrated sufficient diagnostic test accuracy to support their routine use as triage tools during the evaluation of lesions in the oral cavity. For patients seeking care for suspicious lesions, immediate performance of a biopsy or referral to a specialist remains the single most important recommendation for clinical practice. In exceptional cases, when patients decline a biopsy or live in rural areas with limited access to care, the panel suggested that cytologic testing may be used to initiate the diagnostic process until a biopsy can be performed (conditional recommendation, low-quality evidence). CONCLUSIONS AND PRACTICAL IMPLICATIONS: The authors urge clinicians to remain alert and take diligent action when they identify a PMD. The authors emphasize the need for counseling because patients may delay diagnosis because of anxiety and denial.(AU)

Three-dimensional computed tomography and anatomic replicas in surgical treatment planning. Report of a case.

A case that demonstrates the use of three-dimensional computed tomography and anatomic replication in the management of a severe anterolateral open bite deformity is presented. Preoperative surgical treatment planning was facilitated by rehearsal model surgery. Construction of an accurate surgical splint enabled precise positioning of osteotomized segments at surgery.

Radiation myelopathy of the thoracic spinal cord in long term survivors treated with radical radiotherapy using conventional fractionation.

Previous reports on radiation myelopathy of the thoracic spinal cord have attempted to predict tolerance doses as a function of overall treatment time and number of fractions by extrapolation of data from collected myelopathy cases having markedly heterogeneous treatment parameters. A review of long term survivors receiving radical radiotherapy with conventional fractionation for lung and esophageal cancer was undertaken to determine if the proposed tolerance levels were consistent with clinical results in a series of patients constituting the group at risk for developing myelopathy. Spinal cord doses were determined in 58 patients who survived greater than or equal to 18 months following radiotherapy. All patients were treated with megavoltage equipment at dose rates of 200 rads/day continuously (53 patients) or 250 rads/day using split course (5 patients). Tumor doses ranged from 4500 rads to 7000 rads. Seventeen patients (29%) received less than 5000 rads to the thoracic cord, 6 patients (10%) received 5000 rads, and 35 patients (61%) received greater than 5000 rads. There were two patients who developed myelopathy. Review of our data, the clinical data of others and recent experimental results suggest that the slope of tolerance curves for thoracic spinal cord commonly utilized to express time-dose-fractionation relationships may be inappropriate. It is suggested that cord tolerance to well fractionated radiation has been previously underestimated.

A two-piece surgical splint to facilitate hydroxylapatite augmentation of the mandibular alveolar ridge.

Details of the design and fabrication of a two-piece splint that facilitates the HA augmentation of the mandibular alveolar ridge are presented. The use of the splint has eliminated migration of HA particles, reduced elevation of the vestibule, and increased the predictability of the outcome of the procedure.

Autogenous dermal graft coverage of submerged roots in the dog.

Dermal grafts were compared with conventional supraperiosteal recipient beds grafted with split-thickness skin for covering submerged vital roots in six dogs. Several potential advantages of this new technique are suggested.

Radiotherapy of carcinomas of the extrahepatic biliary system.

Carcinomas of the gallbladder and extrahepatic bile ducts carry a dismal prognosis. Due to the proximity of a number of vital structures and their early invasion, these tumors are rarely resectable. Long-term survival or cure is an exception. Results of treatment in 11 patients are reported. In 4 patients, radiotherapy was given as an adjuvant to surgery; in 5 patients the aim was palliation, while 2 patients received potentially curative doses of radiation. Good palliation has been achieved. Long-term, disease-free survival has been observed in some radically treated patients. The results suggest that radiotherapy may contribute to cure not only when used as a surgical adjuvant but also as the sole treatment modality in unresectable but still localized carcinomas of the bile ducts.

Liaison of a county health department medical officer with a group of general practitioners in Hampshire.

A pilot scheme was set up in Hampshire in January 1970, in which a local health authority doctor was "attached" to a group of general practitioners to carry out developmental assessment on infants and young children. Older pre-school children are also seen when necessary, and in all cases possible future educational requirements are considered. Such a scheme reduces duplication of work, increases mutual understanding between general practitioners and local health authority doctors, and helps to make full use of the limited resources of medical manpower.

Age and sex biases in the preservation of human skeletal remains.

Inaccuracies introduced through biases in preservation are a major source of error in paleodemographic reconstructions. Although it is generally assumed that such biases exist, little is known about their magnitude. To investigate this problem, we studied age and sex differences in the preservation of skeletal remains from Mission La Purisima and a prehistoric cemetery (Ca-Ven-110). Comparison of mortality profiles obtained through analysis of skeletal remains and burial records from the mission indicates that biases in preservation can be very significant in poorly preserved skeletal collections. The Purisima burial records show that most of the people interred in the cemetery were either infants or elderly adults. The skeletal remains, in contrast, are predominantly those of young adults. The burial records and skeletal collection produced comparable sex ratios. These results show that age biases in preservation are much more important than sex biases. This conclusion is supported by data on the completeness of the skeletons from La Purisima and Ca-Ven-110. At both sites, the remains of young adults were better preserved than those of children or elderly adults, and the completeness of male and female skeletons was comparable.

The influence of smoking on 3-year clinical success of osseointegrated dental implants.

BACKGROUND: Health risks associated with smoking have been exhaustively documented and include increased incidence of periodontal disease, greater risk of osteitis following oral surgery, and compromised wound healing due to hypoxia. Information related directly to dental implants, although limited, points to higher rates of implant failures among smokers than non-smokers. This paper reports on long-term clinical outcomes of osseointegrated dental implants placed in smokers and non-smokers in a longitudinal clinical study of endosseous dental implants. METHODS: In 1990, the Dental Implant Clinical Research Group (DICRG) of the Department of Veterans Affairs (DVA) launched an 8-year, randomized, prospective clinical study of more than 2,900 endosseous dental implants in more than 800 patients at 32 study centers. Confounding variables, including smoking patterns, were recorded. For this report, new follow-up data were analyzed for two groups: 1) current smokers and 2) those who never smoked combined with those who quit. Most of the variables recorded for each implant were screened on a univariate basis as possible predictors associated with implant survival/failure. Those with P values less than 0.15 and those likely to be a factor of clinical importance were placed in a logistic regression equation and analyzed for a simultaneous effect on survival. A step-wise procedure was used to eliminate those variables that showed the least significance, until only those variables with a Wald chi-square of significance in the presence of others remained. The effects of clustering within patients and of unbalanced distribution within hospitals were standardized to facilitate analysis of influence of demographic variables. The GEE analysis was performed with the patient as the primary cluster. RESULTS: Current data do not support earlier findings that smoking contributes to early implant failure (placement to uncovering). A trend of greater failures in smokers appeared between the time after uncovering and before insertion of the prosthesis. Hydroxyapatite (HA)-coated implants had significantly lower failure rates. For the entire 3-year period, overall failures were significantly higher for smokers than non-smokers. CONCLUSIONS: Results suggest that increased implant failures in smokers are not the result of poor healing or osseointegration, but of exposure of peri-implant tissues to tobacco smoke. Data also suggest that detrimental effects may be reduced by: 1) cessation of smoking; 2) the use of preoperative antibiotics; and 3) the use of HA-coated implants.

Positive effect of surgical experience with implants on second-stage implant survival.

This Dental Implant Clinical Research Group study defined a learning curve for dental implant placement. Implants placed by inexperienced surgeons (< 50 implants) failed twice as often as those placed by experienced surgeons (> or = 50 implants). Implants placed during the first 6, 8, 10, 12, and 16 cases were compared with all others. The greatest difference was seen between the first nine cases and all others (P = .001), with later cases failing significantly less often. Inexperienced surgeons had more failures in the first nine cases (5.9%) than more experienced surgeons (2.4%). Surgeons with little or no previous experience must expect a definite learning curve. Previous experience may transfer and result in a shallower learning curve for subsequent systems.

The influence of 0.12% chlorhexidine digluconate rinses on the incidence of infectious complications and implant success.

The effect of perioperative chlorhexidine on the frequency of infectious complications through stage II was examined. Chlorhexidine was used perioperatively in 54.6% of patients (52.5% of implants) in a Dental Implant Clinical Research Group study with a database of 2,641 implants (595 patients). With chlorhexidine, there was a significant reduction in the number of infectious complications (4.1% vs 8.7%). Two percent of implants failed in the absence of an infectious complication, whereas 12% with infectious complications failed. This sixfold difference is highly significant. Chlorhexidine may reduce microbial complications when used in the immediate perioperative period.

Four cardiorespiratory symptoms as predictors of mortality.

The power of four cardiorespiratory symptoms to predict subsequent mortality has been analysed in data derived from a random sample of the population of Great Britain recruited in 1965 and followed for 12.4 years. The associations of respiratory symptoms with all causes of death (except stroke) and of cardiovascular symptoms with death from coronary heart disease were strong. The trends of these two associations over the 12.4 years of the follow-up differed substantially: the relative death rates associated with respiratory symptoms remained throughout at about the same level, while those associated with cardiovascular symptoms declined after four years. The excess premature deaths associated with presence of one or more symptoms at entry represented about a quarter of the observed deaths of men and one tenth of those of women.

Free autogenous graft coverage of vital retained roots.

The use of free autogenous grafts to the alveolus during root submergence was shown to be a method that might be used to prevent the loss of masticatory mucosa and vestibular depth, which have been regarded as problems associated with the procedure.