Deproteinated bovine bone vs. beta-tricalcium phosphate as bone graft substitutes: histomorphometric longitudinal study in the rabbit cranial vault.

OBJECTIVES: This article aims to study differences in the bone formation and the graft resorption of two bone graft substitutes (BGS). Besides, it is our attempt to observe possible qualitative and quantitative differences in the bone reparation of the outer layer covered by collagen membrane and the uncovered inner layer in close contact with dura mater. MATERIAL AND METHODS: Twelve rabbits were employed. Deproteinized bovine bone (DBB) and ß-tricalcium phosphate (BTCP) were used as BGS. Four subcritical round defects (7 mm) were drilled in the cranial vault, removing both cortical walls. One of the holes was filled with DBB, and other was filled with BTCP. Each symmetrical position to DBB and BTCP was left empty. The whole defect set was covered with a collagen membrane. Histological and morphometric analysis was performed for 1, 4, 8, 16, 32 and 52 weeks. Morphometry measurements were carried out taking into account the whole defect and splitting inner and outer areas. RESULTS: In DBB sites, a rapid bone growth is observed, linking the remaining particles and integrating them into the bone matrix. Permanence of these DBB particles from week 16 onwards restrains the growth of bone fraction. A greater bone growth appears in areas repaired with BTCP than in those repaired with DBB, both in the outer layer (under-membrane) and the inner layer (over dura mater). In DBB sites, a slower growth is observed in the inner layer, with no significant differences in the final bone fraction at both strata. CONCLUSIONS: Both materials favour the closure of the defects provoked. In both cases, a synergistic effect with the collagen membrane is observed. DBB remains integrated in the bone matrix, while BTCP displays a pattern of highly developed progressive resorption with an outstanding bone fraction development.

Maxillary changes and occlusal traits in crania with artificial fronto-occipital deformation.

Artificial fronto-occipital deformation of the cranial vault was typical of pre-Columbian cultures in the central Andean coastal regions. We have studied the influence of this deformation on maxillary and mandibular morphology. Measurements were performed on 86 adult Ancon skulls with anteroposterior deformation. Undeformed skulls from the area of Makatampu (n = 52) were used as the control group. To explore the influence of the deformity on occlusion, the skulls were categorized using the Angle classification and the alignment of the interincisor midline. In the group of deformed skulls, there was an increase in lateral growth of the vault and of the base of the skull (P < 0.001), giving rise to a greater interpterygoid width of the maxilla (P < 0.001), and an increase in the transverse diameter of the palatal vault. The mandible presented an increase in the length of the rami (P < 0.001) and in the intercondylar width, with no alteration of mandibular length. The deformed skulls had normal (class I) occlusion, with no displacement of the midline. The difference in the asymmetry index between the two groups was not statistically significant. Artificial fronto-occipital deformation of the cranial vault provoked compensatory lateral expansion of the base that was correlated with the transverse development of the maxilla and mandible. Occlusion and sagittal intermaxillary position were not affected by the cranial deformity. These results provide evidence of the integration between the neurocranium and the viscerocranium in craniofacial development, and support the hypothesis of a compensatory effect of function.

Speech and swallowing impairment after treatment for oral and oropharyngeal cancer.

OBJECTIVES: To assess the prevalence of speech and swallowing impairment after radical surgery for oral and oropharyngeal cancer from the patient's viewpoint and to examine the association of these functional alterations with selected clinical characteristics regarding patients, tumors, and oncologic treatment. DESIGN: Cross-sectional, multicenter study using a self-administered questionnaire. SETTING: Forty-three hospitals in Germany, Switzerland, and Austria. PATIENTS: A total of 3894 questionnaires about rehabilitation problems after treatment for oral and oropharyngeal squamous cell carcinoma were sent to patients. Of these, 1652 were filled out and returned, and 1334 (80.8%) met the inclusion criteria. MAIN OUTCOME MEASURES: Morbidity associated with treatment of oral and oropharyngeal cancer. RESULTS: Speech problems were reported by 851 patients (63.8%), and swallowing problems were reported by 1006 patients (75.4%). The variables that presented a significant association with speech and swallowing impairment were sex, tumor location, pTNM stages, stage of tumor, treatment modality, and reconstruction type. CONCLUSIONS: This survey, based on patient perception, suggests that those who undergo radiotherapy associated with the surgical removal of a tumor, have late-stage tumors (III-IV), or have tumors located in the floor of the mouth should be informed of the greater risk of persistent severe speech and swallowing problems.

Immunohistochemical expression of HIF-1alpha in response to early myocardial ischemia.

This study aims to evaluate the effects of ischemia on the myocardial fibers and the expression of the transcriptional factor for angiogenesis hypoxia-inducible factor-1 alpha (HIF-1alpha) in human heart specimens. We have prospectively analyzed the HIF-1alpha expression in human ischemic hearts with the ABC-inmunohistochemistry technique and amplification by biotinylated tyramide. The relationship between the expression of HIF-1alpha and the temporal evolution of ischemia has also been evaluated. As pathomorphological diagnosis of early myocardial ischemia has many problems in human autopsy material with less than 4 to 6 h after clinical onset, we suggest that HIF-1alpha is helpful in the early acute myocardial infarction diagnosis, so it stains necrotic areas within the first 2 h. The amplification procedure provides a higher intensity of the final staining without losing specificity. It is concluded that in normal cardiac fibers, basal expression of HIF-1alpha is not appreciable, but it steadily increases after ischemia. With regard to the practical applicability in forensic field, our observations suggest that positive immunohistochemical expression of HIF-1alpha on heart samples may be used as a reliable indicator of myocardial damage in cases without cardiac lesion evidence, using conventional microscopy. This method is especially useful and may provide definitive proof of myocardial ischemia in unexpected deaths without previous symptoms, or in forensic cases with a short period of clinical manifestations. In addition, it may have been involved in possible future cardiovascular therapies.

Valor predictivo de la candidiasis oral como marcador de evolución a SIDA / Predictive value of oral candidiasis as a marker of progression to AIDS

Objetivo: Determinar la validez de la candidiasis oral (CO) como marcador clínico de evolución en los pacientes infectados porel Virus de la Inmunodeficiencia Humana. Diseño del estudio: En 1992, se efectuó una exploración oral a un colectivo de 200 pacientes infectados por VIH, con una edad media de 36,8±7 años (rango 25-46 años) para establecer el diagnóstico de CO. Se registraron las variables edad, sexo, tiempode evolución de la enfermedad, conducta de riesgo, número de linfocitos CD4/µL, estadio clínico y tratamiento antirretroviral. De los 200 pacientes del grupo de estudio, 157 no cumplían criterios de SIDA en el momento de la exploración basal y a éstos se les efectuó un seguimiento semestral hasta que cumplieron dichos criterios, concluyendo el estudio al final de 2001. Resultados: De los 157 pacientes seleccionados, 71 (45,2%) no presentaron CO y de éstos el 28,7% evolucionó a SIDA durante el período de seguimiento. De los 86 (54,8%) pacientes con CO, el 48,2% evolucionó a SIDA (RR=2,71). Al trasladar el origen del estudio al año 1997 cuando se inició la administración de la terapia antirretroviral de alta eficacia (TAAE), no se observaron diferencias en el porcentaje de pacientes que evolucionaron a SIDA en relación a la existencia o no de CO en la exploración basal. El análisis multivariante demostró que la asociación de la variable de exposición CO con la evolución a SIDA no alcanzó un valor predictivo. Conclusiones: El valor pronóstico a largo plazo de la CO, no se ha determinado en pacientes que reciben terapia antirretroviral de alta eficacia (TAAE). La recuperación inmunológica y la disminución de enfermedades oportunistas observadas tras la administración de TAAE, hacen que muchos pacientes que alcanzaron la condición de SIDA no cumplan en la actualidad dichos criterios, lo que obliga a renovar la propia definición del síndrome para poder evaluar marcadores de pronóstico

Objective: To determine the validity of oral candidiasis (OC) as a clinical marker of progression in patients with human immunodeficiency virus infection. Study design: In 1992, an oral examination was carried out on a group of 200 HIV-infected patients with a mean age of 36.8± 7 years (range 25-46 years) to establish the diagnosis of OC. The following variables were recorded: age, sex, duration of the disease, risk behaviour, CD4 lymphocyte count, clinical stage and antiretroviral treatment. Of the 200 patients in the groupe valuated, 157 did not fulfil the criteria for AIDS at the time of the base line examination; these patients constitute the study group and underwent 6-monthly follow-up until they fulfilled these criteria. The study was concluded at the end of 2001. Results: Of the 157 patients selected, 71 (45.2%) did not present OC and, of these, 28.7% progressed to AIDS during the follow up period. Of the 86 (54.8%) patients with OC, 48.2% progressed to AIDS (RR= 2.71). If the start date of the study was taken as 1997, when highly active antiretroviral therapy (HAART) was introduced, no differences were found in the percentage of papatients who progressed to AIDS with respect to the presence or absence of OC at the baseline examination. Multivariate analysis demonstrated that the association of the presence of OC with progression to AIDS did not reach a predictive value. Conclusions: The long-term prognostic value of OC has notbeen established in patients receiving highly active antiretroviral therapy (HAART). The immunological recovery and the reduction in the number of opportunistic diseases observed after the administration of HAART means that many patients who developed AIDS do not currently satisfy these criteria, making a review of the definition of the syndrome it self a necessity in order to be able to evaluate prognostic markers

Predictive value of oral candidiasis as a marker of progression to AIDS.

OBJECTIVE: To determine the validity of oral candidiasis (OC) as a clinical marker of progression in patients with human immunodeficiency virus infection. STUDY DESIGN: In 1992, an oral examination was carried out on a group of 200 HIV-infected patients with a mean age of 36.8 +/- 7 years (range 25-46 years) to establish the diagnosis of OC. The following variables were recorded: age, sex, duration of the disease, risk behaviour, CD4 lymphocyte count, clinical stage and antiretroviral treatment. Of the 200 patients in the group evaluated, 157 did not fulfil the criteria for AIDS at the time of the baseline examination; these patients constitute the study group and underwent 6-monthly follow-up until they fulfilled these criteria. The study was concluded at the end of 2001. RESULTS: Of the 157 patients selected, 71 (45.2%) did not present OC and, of these, 28.7% progressed to AIDS during the followup period. Of the 86 (54.8%) patients with OC, 48.2% progressed to AIDS (RR= 2.71). If the start date of the study was taken as 1997, when highly active antiretroviral therapy (HAART) was introduced, no differences were found in the percentage of patients who progressed to AIDS with respect to the presence or absence of OC at the baseline examination. Multivariate analysis demonstrated that the association of the presence of OC with progression to AIDS did not reach a predictive value. CONCLUSIONS: The long-term prognostic value of OC has not been established in patients receiving highly active antiretroviral therapy (HAART). The immunological recovery and the reduction in the number of opportunistic diseases observed after the administration of HAART means that many patients who developed AIDS do not currently satisfy these criteria, making a review of the definition of the syndrome itself a necessity in order to be able to evaluate prognostic markers.

Comparative study of locking plates in mandibular reconstruction after ablative tumor surgery: THORP versus UniLOCK system.

PURPOSE: This retrospective study compared 2 types of rigid locking plates (THORP and UniLOCK; Stratec Medical, Oberdorf, Switzerland) in 107 patients undergoing reconstruction for bridging mandibular defects following ablative tumor surgery. PATIENTS AND METHODS: From January 1993 to December 2000, 107 patients were reconstructed following ablative tumor surgery with 57 THORP plates and 50 UniLOCK plates. Study follow-up ranged from 18 to 87 months (average, 32 months). Complications were categorized into delayed wound healing, infection, plate exposure, and plate fracture, taking into account the type and timing of reconstruction. RESULTS: Overall type and number of complications show no statistically significant differences between THORP and UniLOCK groups. Infection was the most frequent type of complication (THORP, 30; UniLOCK, 32). Others included delayed wound healing (THORP, 13; UniLOCK, 12), plate exposure (THORP, 8; UniLOCK, 7), and plate fracture (THORP, 5; UniLOCK, 1). Plates were removed in 22 THORP and 11 UniLOCK plates. The most frequent reason for plate removal in both groups was infection. Other reasons for plate removal include tumor recurrence, plate fracture, plate exposure, or a combination of reasons. CONCLUSIONS: THORP and UniLOCK plates do not present statistically significant differences in the parameters studied. Nevertheless, the UniLOCK group had slightly better results. Considering that the THORP system is much bulkier and its screws bigger, our results lead to the conclusion that bridging osteosynthesis with a 2.4 UniLOCK system is adequate for plate reconstruction of mandibular defects.

Marginal flap versus paramarginal flap in impacted third molar surgery: a prospective study.

OBJECTIVE: A clinical prospective study was carried out to compare 2 flap designs-marginal and paramarginal-that are used during impacted third molar surgery. MATERIALS AND METHODS: Twenty-seven healthy patients (ages 17 to 31 years) who underwent surgical removal of 4 impacted third molars, including 54 lower and 54 upper, were included. A marginal flap was used in 1 randomly chosen half of the jaw, and a paramarginal flap was used in the other half. The influence of these flaps on wound healing, periodontal pocket depth of the adjacent second molar, pain, trismus, and swelling was studied. RESULTS: Wound dehiscences developed in 8 paramarginal flap cases, whereas none occurred with the use of a marginal flap. The buccal and distal probing depths of the adjacent second molar were significantly bigger in marginal flaps at 5 and 10 days after surgery. However, the probing depth was similar with the use of both techniques at 3 months. Pain, trismus, and swelling were similar with both techniques. CONCLUSIONS: We found no advantages to the use of a paramarginal flap instead of a traditional marginal flap for removing impacted third molars.