Maxillary sinus augmentation with iliac autograft - a health-economic analysis.

PURPOSE: To estimate and compare the costs of maxillary sinus augmentation performed with autologous bone graft either from the iliac crest or from local bone harvested from the mandibula. To evaluate post-operative health-related quality-of-life parameters for patients subjected to sinus augmentation and iliac bone surgery. MATERIAL AND METHODS: The hospital records of 14 patients subjected to sinus augmentation with iliac autograft, and 14 patients treated with local autograft, were analysed with regard to costs related to surgery, hospitalization and sick leave. Post-operative health parameters were assessed with a questionnaire. RESULTS: Mean hospital costs, administration excluded, for sinus augmentation with iliac autograft was €3447. Policlinic treatment alternatives e.g. local bone autograft with or without bone substitutes, rendered costs of approximately 42% thereof. The loss of production for a worker was 41% of the total cost (€9285). With regard to health-related quality-of-life and post-operative morbidity, most of the patients had recovered 14 days after the iliac graft surgery. CONCLUSION: The cost for a sinus augmentation with iliac surgery exceeds that of a policlinic procedure manifold. Provided that a policlinic operation with local bone, with or without bone substitute, renders an adequate end result, the economic gain would be substantial and post-operative morbidity would be greatly reduced.

TMD before and after correction of dentofacial deformities by orthodontic and orthognathic treatment.

The aims of the study were to investigate the alteration of temporomandibular disorders (TMD) after correction of dentofacial deformities by orthodontic treatment in conjunction with orthognathic surgery; and to compare the frequency of TMD in patients with dentofacial deformities with an age and gender matched control group. TMD were evaluated in 121 consecutive patients (treatment group), referred for orthognathic surgery, by a questionnaire and a clinical examination. 18 months after treatment, 81% of the patients completed a follow-up examination. The control group comprised 56 age and gender matched subjects, of whom 68% presented for follow-up examination. TMD were diagnosed according to research diagnostic criteria for TMD. At baseline examination, the treatment group had a higher frequency of myofascial pain (P=.035) and arthralgia (P=.040) than the control group. At follow-up, the frequencies of myofascial pain, arthralgia and disc displacement had decreased in the treatment group (P=.050, P=.004, P=.041, respectively). The frequency of TMD was comparable in the two groups at follow-up. Patients with dentofacial deformities, corrected by orthodontic treatment in conjunction with orthognathic surgery, seem to have a positive treatment outcome in respect of TMD pain.

Bone substitute as an on-lay graft on rat tibia.

OBJECTIVES: To investigate the capacity of Cerament, an injectable bone substitute, to guide bone generation from a cortical surface. MATERIALS AND METHOD: Cerament was applied to the cortical surface of rat tibiae and investigated histologically after 3, 6 and 12 weeks, using a procedure similar to that performed in sham-operated rats. RESULTS: In both groups, the thickness of the bone cortex increased significantly from 473 + or - 58 microm (mean + or - SD) at day 0 to 1193 + or - 255 microm (Cerament) and 942 + or - 323 microm (sham) after 3 weeks. In the Cerament group, the new bone thickness remained constant (1258 + or - 288 microm) until the end of the experiment at 12 weeks, while the sham group demonstrated a return to initial cortical thickness (591 + or - 73 microm) at 12 weeks. The newly formed bone in the Cerament group was highly trabecular after 3 weeks but attained a normal trabecular structure of the cortex after 12 weeks. CONCLUSION: Cerament may guide bone generation from an intact cortical bone surface. Although bone remodeling speed may differ between rats and humans, our study indicates that Cerament may become a useful alternative to autologous bone, both to fill defects and to increase bone volume by cortical augmentation.

Jaw fractures diagnosed and treated at Malmö University Hospital: a comparison of three decades.

The aim was to report the distribution, frequency and aetiology of jaw fractures in patients treated at the University Hospital, Malmö, 1993-2003 and to compare two previous studies from 1952-1962 and 1975-1985. In 1993-2003, 461 patients, 137 women (mean age 42 years; range 15-82) and 324 men (mean age 28 years; range 17-59) were diagnosed and treated. Women were significantly older than men (P<0.001). The most frequent cause of jaw fractures was falls in women (45%). In men, interpersonal violence (46%) was most common followed by road traffic accidents (RTAs) (24%) mostly involving bicycles (14%). The frequency of falls in women and men was significantly different (P<0.001) as was the difference between violence in men and women (P<0.001). The proportion of fractures caused by RTAs was significantly higher in 1952-1962 than in 1993-2003 (P<0.001). There was a significant increase in the proportion of fractures caused by violence between the two studies (P=0.007). In 1993-2003 the proportion of fractures in women due to falls was significantly higher than in 1952-1962 (P=0.006). Violence has replaced RTAs as the main cause for jaw fractures in men; for women falling is the commonest cause.

Neurosensory disturbance after sagittal split and intraoral vertical ramus osteotomy: as reported in questionnaires and patients' records.

This retrospective study aimed at evaluating the long-term incidence of neurosensory disturbance (NSD) after sagittal split osteotomy (SSO) and intraoral vertical ramus osteotomy (IVRO). Furthermore, a comparison was made between the results obtained by questionnaires and information in the patient records in the evaluation of nerve function. Finally, the degree of discomfort caused by the NSD was evaluated. One hundred and twenty-nine patients, who underwent IVRO (79 patients) and SSO (50 patients), were included. Questionnaires were mailed to the patients at least one year after the operation. The records of all patients, who returned the questionnaires, were reviewed. The results of NSD obtained by questionnaires and records differed indicating a disagreement between the judgement of the surgeon and the patient's opinion. Long lasting NSD was underestimated by the surgeon as compared to the patient's subjective symptom. Long lasting NSD was reported in 7.5% (questionnaire), 3.8% (record) after IVRO and in 11.6% (questionnaire) and 8.1% (record) after SSO.

The protective effect of zinc on rosin and resin acid toxicity in human polymorphonuclear leukocytes and human gingival fibroblasts in vitro.

Combinations of rosin and zinc are used in dentistry as components of periodontal dressings and cements and as root canal sealers. The composition and properties of rosins differ largely depending on source and refinement processes. Rosin (colophony) is composed of approximately 70% resin acids. In order to study the toxic effects of different natural rosins and purified resin acids and the detoxifying effects of zinc, these compounds were analyzed and tested on human polymorphonuclear leukocytes (PMN cells) and human gingival fibroblasts using the radiochromium release method. The rosins and the pure resin acids showed a strong dose-related cytotoxicity, which was inhibited by increased zinc concentrations. The purified resin acids (isopimaric, levopimaric, and neoabietic acid) were more toxic than the natural rosins. The contents of these resin acids might explain the difference in toxicity of the rosins tested. It is concluded that rosin and zinc are not to be considered inert compounds and that the cytoprotective effects of zinc and its role in dentistry products merit further investigations.

The effect of zinc on bacterial phagocytosis, killing and cytoprotection in human polymorphonuclear leucocytes.

An in vitro study examining the effects of zinc treatment on human PMN cell phagocytosis and killing of Staphylococcus aureus and Staphylococcus epidermidis and the cytoprotection of zinc against staphylococcal toxins. Phagocytosis was studied by transmission electron microscopy using different microbiological techniques, one of which was designed to follow the kinetics of bacterial killing. No effect was found on phagocytosis and bacterial killing. The cytotoxic effects of a crude toxin and an alpha-toxin extracted from Staphylococcus aureus preparations were studied on human PMN cells using the standard 51Cr release assay. Both toxins induced a dose-dependent leakage of 51Cr, indicating cell membrane damage. These results were confirmed by electron microscopy during the phagocytosis of S. aureus, where severe PMN cellular degeneration was observed. The addition of zinc to PMN cells strongly inhibited the release of 51Cr. In conclusion, our results show that zinc in higher than physiological concentrations does not inhibit PMN cell functions such as phagocytosis and intracellular killing of S. aureus and S. epidermidis. The addition of zinc may be beneficial in certain clinical situations, such as wound healing, zinc deficiency and infections involving toxin-producing bacteria, e.g. S. aureus.

Antimicrobial screening of zinc in the absence or presence of oleoresins and various resin acids.

Zinc and oleoresins are the main components of several wound dressings, and are also frequently used in root canal treatment. The in vitro antibacterial effects of zinc, six highly purified resin acids and two commercial oleoresins alone or combined in varying proportions were analysed. Oleoresins are composed of approximately 90% resin acids and the most common acids were included in this study. The antibacterial activity of the various chemicals was estimated using a Bioscreen robot analyser, which allowed 24 h kinetic documentation of bacterial growth. The bacteria employed were reference species commonly occurring on human skin or of oral origin. Zinc as well as the oleoresins and the pure resin acids all showed antibacterial activity when present in growth media, but the sensitivity of the bacteria varied. The presence of resin acids and oleoresins increased the antibacterial effect of zinc to varying degrees depending on the combination and the bacterial species tested. The results of the present study indicate that zinc, resin acids, or oleoresins alone, as well as combined, show antibacterial activity against selected aerobic Gram-positive and anaerobic Gram-negative bacteria.

Comparison of three test methods used for the diagnosis of candidiasis.

A total of 266 specimens was taken from oral mucosa or dentures of 88 patients with suspected Candida-infected oral mucosa. One-third of the debris from each sample was cultured on Microstix-Candida (C), strips, one-third was cultured on Oricult-N-plates, and the rest was collected on glass plates and stained by the periodic acid-Schiff (PAS) method. The PAS-stained samples were analyzed under the light microscope for the presence of Candida hyphae. The other samples (Oricult-N or Microstix-C) were studied visually, according to the manufacturer's recommendation. PAS-stained specimens showed significantly less often positive results than those of the two culture methods. These data suggest that oral candidiasis may be incorrectly diagnosed if based upon results obtained with the culture methods. It is also possible that the PAS-staining method yielded false negative findings. This possibility should always be considered, especially if other findings and symptoms disagree with the test results obtained.

Neutralizing effect of zinc oxide on dehydroabietic acid-induced toxicity on human polymorphonuclear leukocytes.

The cytotoxic effect of dehydroabietic acid (DHAA), a resin acid found in rosin, was studied on human polymorphonuclear leukocytes (PMN) using leakage of 51Cr from prelabeled cells, supravital staining, and transmission electron microscopy. DHAA caused a strong dose-related release of 51Cr, a high uptake of trypan blue, and total cell necrosis as seen in transmission electron microscopy. Albumin slightly reduced the toxic effects, whereas the addition of zinc in various forms strongly inhibited these toxic effects of DHAA in the concentration range 10-500 micrograms/mL. In the presence of albumin, zinc oxide as a suspension inhibited the damage of the cell membranes more than a filtrate of zinc oxide, indicating a subsequent slow release of zinc from the zinc oxide.

Neutralizing effect of zinc oxide on dehydroabietic acid-induced toxicity on human polymorphonuclear leukocytes.

The cytotoxic effect of dehydroabietic acid (DHAA), a resin acid found in rosin, was studied on human polymorphonuclear leukocytes using leakage of 51Cr from prelabeled cells, supravital staining, and transmission electron microscopy. DHAA caused a strong dose-related release of 51Cr, a high uptake of trypan blue, and total cell necrosis, as seen in transmission electron microscopy. Albumin slightly reduced the toxic effects, whereas the addition of zinc in various forms strongly inhibited these toxic effects of DHAA in the concentration range of 10-500 micrograms/mL. In the presence of albumin, zinc oxide as a suspension inhibited the damage of the cell membranes more than a filtrate of zinc oxide, indicating a subsequent slow release of zinc from the zinc oxide.

Planning and control of vertical dimension in Le Fort I osteotomies.

Depending on the different anatomy of the soft and hard tissues, concavity or convexity of the face, measurements of inferior or superior repositioning of the maxilla may be less predictable when using only the osteotomy site for this calculation. A more reliable method would be to measure the distance from a bone mark in the forehead to the incisor edges. This method has been practiced by our clinic during the past five years. The method is thought to offer a more accurate estimation of the position of the upper anterior teeth in relation to the lip, although one must anticipate a certain degree of postoperative relapse especially concerning inferior repositioning. In order to evaluate the accuracy of our method, a comparison has been made of the calculated vertical repositioning and the surgical results in two groups. In group I (12 individuals) conventional estimation of maxillary repositioning in the osteotomy line was made; in group II (12 individuals) measurements were made from a bone mark on the forehead to the incisor edges. A satisfying correlation was found between calculated and achieved results in both groups. In comparison between calculated and immediate postoperative measurements the results showed no statistically significant difference between the two methods.

The effect of zinc oxide on Staphylococcus aureus and polymorphonuclear cells in a tissue cage model.

The effect of zinc oxide on S. aureus (209 P) was studied in steel net tissue cages implanted subcutaneously in guinea pigs and rabbits. Zinc oxide installed in the tissue cages created high, sustained concentrations of zinc in the cage fluid throughout the study. In a concentration of 22 mmol/l zinc oxide reduced viable counts in tissue cage fluid inoculated with S. aureus. No deleterious effect was observed on polymorphonuclear cell function.

Antibacterial effect of zinc oxide in vitro.

Antibacterial activity, zinc concentrations and pH were measured in Müller-Hinton broth containing different amounts of zinc oxide and inoculated with Staphylococcus aureus (10(6) colony forming units/ml). The minimum inhibitory concentrations (MIC) of zinc oxide to different clinical isolates were determined using the Müller-Hinton agar dilution tests. Gram-positive bacteria were most susceptible. Gram-negative aerobic bacteria and streptococci were usually not inhibited even at the highest concentrations used (1024 micrograms/ml), but staphylococci--particularly some isolates of Staphylococcus epidermidis--were sensitive enough to allow determination of their MIC.

The extent of coprophagy in rats with differing iron status and its effect on iron absorption.

The purpose of this study was to determine the prevalence of coprophagy in rats with differing iron status and its effect on the measurement of iron absorption from test meals with and without bran. Two experiments were performed using radioisotope-labelled microspheres added as a non-digestible marker for the ingested faeces and the diet and 59Fe added as a marker for the nonhaem iron in the test meal. In this study, coprophagy occurred at group mean rates of between 5 and 22% and was independent of the iron status of the rats or the presence or absence of bran in the diet. The relative absorption of iron, measured as the retention of 59Fe from a single meal, was affected to the same extent in groups with the same iron status, if it was affected at all. Thus comparisons of iron absorption from diets with and without bran should not be affected by coprophagy.