Oral lichen planus (OLP), oral lichenoid lesions (OLL), oral dysplasia, and oral cancer: retrospective analysis of clinicopathological data from 2002-2011.

INTRODUCTION: This 10-year retrospective study analyzed the incidence of malignant transformation of oral lichen planus (OLP). The study also included dysplasia and oral lichenoid lesion (OLL) in the initial biopsy as a potential differential diagnosis. MATERIAL AND METHODS: A total of 692 scalpel biopsies were taken from 542 patients (207 [38.2%] men and 335 [61.8%] women). Clinical and histopathological parameters were analyzed. RESULTS: The parameters gender (p = 0.022) and smoking behavior (p < 0.001) were significantly associated with the severity of diagnosis. Mucosal lesions with an ulcerative appearance (p = 0.006) and those located on the floor of the mouth (p < 0.001) showed significantly higher degrees of dysplasia or were diagnosed as oral squamous cell carcinoma (OSCC). Smoking and joint disease appeared to be significant risk factors. Treatment with tretinoin in different concentrations (0.005-0.02%) significantly improved diagnosis. Twelve patients (8 female, 4 male) showed malignant transformation to OSCC within an average period of 1.58 years. The malignant transformation rate (MTR) was higher for OLL (4.4%) than OLP (1.2%). If the first biopsy showed intraepithelial neoplasia, the risk of developing OSCC increased (by 3.5% for squamous intraepithelial neoplasia (SIN) II and by 6.7% for SIN III). CONCLUSION: Although we cannot rule out that OLP is a premalignant oral condition, we can confirm that OLP had the lowest MTR of all diagnoses.

Development of the frontal sinus following bilateral fronto-orbital osteotomies.

The presence of frontal sinuses following bilateral fronto-orbital advancement is discussed controversially in the literature. In a retrospective study, 33 patients (18 male and 15 female) were operated on between 1982 and 1993, with at least one year postoperative follow-up and with a minimum age of 6 years at the end of the follow-up period following bilateral fronto-orbital remodelling, were included. The average age at which the procedure was performed was 29 months with a minimum of 3 months and a maximum of 7.8 years. The study presented shows a pneumatization of the frontal sinus in 72.7% of 33 patients following bilateral fronto-orbital advancement. The first radiographic signs of sinus development were detected between the ages of 4 and 11, average 8.3 years. There were no statistically proven correlations between frontal sinus pneumatization and age at operation or the amount of advancement or sex of the patients. Surgical enlargement of the cranium by frontal advancement with adequate stabilization results in an enlargement of the neurocranium, thereby decreasing pressure on the inner frontal cortex and allowing frontal sinus pneumatization to proceed normally. Hence, the development of a frontal sinus may be a reflection of the effectiveness of the surgical therapy.

[Allo-transfusion saving measures in maxillofacial surgery]. / Fremdblutsparende Massnahmen in der Kiefer-und Gesichtschirurgie.

In terms of a prospective clinical study between June 1994 and May 1996, in 204 patients undergoing maxillo-facial surgeries with a expected blood loss of more than 500 ml a protocol of bloodsaving measures was followed. By means of an additional retrospective study, the consumption of homologous blood and the amount of bloodsaving measures between June 1990 and May 1994 was evaluated. Bloodsaving measures were consisting from acute normovolemic hemodilution, controlled moderate hypotension, cell saving, preoperative autologous blood donation, and administration of rh-erythropoetine. The methoda were applied isolated as well as in combination. Special concerns were given to a stable intraoperative homeostasis and to the acceptance of a low hematocrit perioperatively. Aim of the study was to investigate if, following the protocol, even in major maxillofacial procedures homologous blood transfusions almost completely can be avoided. Out of the 204 patients in the prospective study, only 30 received homologous blood. For the period June 94 to May 96, the reduction of the number of patients receiving homologous blood in relation to the period June 90 to May 94 was 83%. The results indicate that in the years 94 to 96 twice as much patients received bloodsaving measures. These led to a reduction of homologous blood consumption for 427 units in 1990 to 56 units 1996 (p < 0.001). If three measures, i.e. normovolemic hemodilution, cell saving, and hypotension were combined, the need of blood transfusion was at the minimum level. The effective reduction of homologous blood transfusion by consequent application of bloodsaving measures can with these data obviously be demonstrated.

[Preoperative diagnosis of complex craniofacial syndromes]. / Präoperative Diagnostik komplexer kraniofazialer Syndrome.

The aim of this study was to evaluate stereolithography as a tool in craniofacial surgery. The indications were classified according to the usefulness of stereolithography for different craniofacial pathologies. Stereolithography models of 21 patients were built; in three cases two models were made. The age of the 7 male and 14 female patients was 17 years on average (range: 15 months-44 years). First a helical volume CT scan of the anatomical region was performed. After transformation of the data set, the models were built by an SLA 250 stereolithography apparatus (3D-Systems, Valencia, Calif., USA), steered by FORM-IT/DCS-Software (University of Zurich, Switzerland). The stereolithography models were constructed by superposition of epoxy resin slices of 0.05 mm thickness, which were polymerized by a helium-cadmium laser. These models were classified according to the indication for stereolithography, the operation performed, the relevance for surgical planning and the usefulness for the fabrication of implants and protheses. In craniofacial syndromes, severe asymmetries of the viscerocranium, large skull defects and before surgical correction of hypertelorism these models provided important additional information for the surgeon. Before complex interventions in these fields the construction of a stereolithography model should be considered. In multiple fractures consolidated in dislocation, the models proved to be less useful.

[Fronto-orbital corrections and development of the frontal sinus]. / Frontoorbitale Korrekturen und Stirnhöhlenentwicklung.

The development of frontal sinuses following bilateral fronto-orbital advancement is a topic of controversial discussion in the literature. In a retrospective study on 33 patients (15 girls and 18 boys) the development of the frontal sinus was examined radiologically. Only patients with a minimum age of 6 years and with at least 1 year of postoperative follow-up were included. The radiological reference for the frontal sinus development consisted of pneumatisation at or above the level of the supraorbital rims, as projected din postero-anterior cephalograms. According to these criteria a frontal sinus development was seen in 72.7% of our patients. There was no statistically proven correlation between sinus development and the sex of the patient, age at surgery or the amount of advancement. With the exception of severe cases of Crouzon's disease we usually expect normal development of the frontal sinus following bilateral fronto-orbital correction.

[Cranial development after corrective skull surgery in craniosynostosis]. / Wachstumsverhalten nach Schädelkorrekturen bei Kraniosynostosen.

Craniofacial development may be potentially implicated after vault corrections in cases of craniosynostosis. The aim of this prospective study was the investigation of the surgical effect on calvaria growth, correlating the percentiles of a group of patients before and after craniosynostosis correction in relation to the normal percentiles of growth. The patient population consisted of 71 children; the postoperative follow-up time in 57 patients was more than 12 months. Of the children followed up, 36 were male and 21 female. Thirty-six cases involved untreated non-syndromic craniosynostosis; the remaining 21 were syndrome cases. The patient ages ranged from 16 to 27 months. In 11 cases correction of an occipital craniosynostosis was carried out. The fronto-occipital circumference was registered in accordance with Prader's percentile table. The operative method included a fronto-parietal craniotomy, the temporary removal and shaping of the fronto-orbital band and a vault cranioplasty. During follow-up 13 patients treated with fronto-orbital advancement in cases of isolated craniosynostosis remained in the registered percentile curve. In 13 patients a change to a lower percentile curve was confirmed; 1 patient changed to a higher curve. In cases of syndromic craniosynostosis 10 patients remained in the post-operatively registered percentile curve; 8 patients changed to a lower and 1 patient to a higher percentile curve. No growth restriction of the reshaped calvaria after surgical correction of craniosynostosis was observed. No significant difference was found in the potential calvaria growth between syndromic and isolated craniosynostosis.

[Occipital correction in scapho- and plagiocephaly]. / Okzipitale Korrektur bei Skapho- und Plagiozephalie.

The operation technique and the results after occipital correction in children with plagiocephaly and scaphocephaly are reported. The indication for the intervention is provided by aesthetic and functional considerations. The outcome is very good; the growth of the skull follows the same range of percentiles as preoperatively and normal mental development is seen.

[Pre-operative diagnosis of complex craniofacial syndromes]. / Präoperative Diagnostik komplexer kraniofazialer Syndrome.

The aim of this study was to evaluate stereolithography as a tool in craniofacial surgery. The indications were classified according to the usefulness of stereolithography for different craniofacial pathologies. Stereolithography models of 21 patients were built; in three cases two models were made. The age of the 7 male and 14 female patients was 17 years on average (range: 15 months-44 years). First a helical volume CT scan of the anatomical region was performed. After transformation of the data set, the models were built by an SLA 250 stereolithography apparatus (3D-Systems, Valencia, Calif., USA), steered by FORM-IT/DCS-Software (University of Zurich, Switzerland). The stereolithography models were constructed by superposition of epoxy resin slices of 0.05 mm thickness, which were polymerized by a helium-cadmium laser. These models were classified according to the indication for stereolithography, the operation performed, the relevance for surgical planning and the usefulness for the fabrication of implants and protheses. In craniofacial syndromes, severe asymmetries of the viscerocranium, large skull defects and before surgical correction of hypertelorism these models provided important additional information for the surgeon. Before complex interventions in these fields the construction of a stereolithography model should be considered. In multiple fractures consolidated in dislocation, the models proved to be less useful.

[Fronto-orbital correction and frontal sinus development]. / Frontoorbitale Korrekturen und Stirnhöhlenentwicklung.

The development of frontal sinuses following bilateral fronto-orbital advancement is a topic of controversial discussion in the literature. In a retrospective study on 33 patients (15 girls and 18 boys) the development of the frontal sinus was examined radiologically. Only patients with a minimum age of 6 years and with at least 1 year of postoperative follow-up were included. The radiological reference for the frontal sinus development consisted of pneumatisation at or above the level of the supraorbital rims, as projected in postero-anterior cephalograms. According to these criteria a frontal sinus development was seen in 72.7% of our patients. There was no statistically proven correlation between sinus development and the sex of the patient, age at surgery or the amount of advancement. With the exception of severe cases of Crouzon's disease we usually expect normal development of the frontal sinus following bilateral fronto-orbital correction.

[Cranial development and growth following treatment of craniosynostosis skull deformities]. / Wachstumsverhalten nach Schädelkorrekturen bei Kraniosynostosen.

Craniofacial development may be potentially implicated after vault corrections in cases of craniosynostosis. The aim of this prospective study was the investigation of the surgical effect on calvaria growth, correlating the percentiles of a group of patients before and after craniosynostosis correction in relation to the normal percentiles of growth. The patient population consisted of 71 children; the postoperative follow-up time in 57 patients was more than 12 months. Of the children followed up, 36 were male and 21 female. Thirty-six cases involved untreated non-syndromic craniosynostosis; the remaining 21 were syndrome cases. The patient ages ranged from 16 to 27 months. In 11 cases correction of an occipital craniosynostosis was carried out. The fronto-occipital circumference was registered in accordance with Prader's percentile table. The operative method included a fronto-parietal craniotomy, the temporary removal and shaping of the fronto-orbital band and a vault cranioplasty. During follow-up 13 patients treated with fronto-orbital advancement in cases of isolated craniosynostosis remained in the registered percentile curve. In 13 patients a change to a lower percentile curve was confirmed; 1 patient changed to a higher curve. In cases of syndromic craniosynostosis 10 patients remained in the post-operatively registered percentile curve; 8 patients changed to a lower and 1 patient to a higher percentile curve. No growth restriction of the reshaped calvaria after surgical correction of craniosynostosis was observed. No significant difference was found in the potential calvaria growth between syndromic and isolated craniosynostosis.

[The occipital correction in plagiocephaly and scaphocephaly]. / Okzipitale Korrektur bei Skapho- und Plagiozephalie.

The operation technique and the results after occipital correction in children with plagiocephaly and scaphocephaly are reported. The indication for the intervention is provided by aesthetic and functional considerations. The outcome is very good; the growth of the skull follows the same range of percentiles as preoperatively and normal mental development is seen.

The pterygoid hamulus as a pain-inducing factor. A report of a case and a radiographic study.

A case is reported of a patient suffering from untraceable pain in the palate. The hyperplastic pterygoid hamulus appeared to be the cause of his discomfort. A computed tomography study on 20 adult patients revealed a wide variation in the anatomy of this region, but a fairly consistent pattern in the left-right relationship in the same patient.

Complications following arthroscopy of the temporomandibular joint: analysis covering a 10-year period (451 arthroscopies).

451 arthroscopies of the temporomandibular joint (TMJ) have been performed on 373 patients during 10 years of clinical experience. The complication rate was low (1.77%). Most complications were transient, consisting mainly of temporary deficits of the 5th and 7th cranial nerves. No patient required arthrotomy because of complications, but one patient had to undergo angiography and embolization of a traumatic aneurysm of the superficial temporal artery secondary to arthroscopy.

[Severe complications after surgical removal of wisdom teeth]. / Schwerwiegende Komplikationen nach operativer Weisheitszahnentfernung.

Between 1988 and 1992, 14,765 impacted third molars were removed in the Department for Maxillofacial Surgery of the University Hospital and Dental Clinic in Zurich. A report on significant complications is given and compared to previous studies. Special attention is given to major complications which needed hospitalisation and/or surgical intervention, like secondary infection of the head and neck region, mediastinal emphysema, mandibular fractures and dislocation of third molars, which could not be removed under local anaesthesia. Mediastinitis, excessive bleeding or permanent damage to cranial nerves were not encountered in these 5 years, but are reviewed. Serious postoperative complications can be life-threatening if not diagnosed correctly and managed accordingly.

The use of the Cell Saver in transoral maxillofacial surgery: a preliminary report.

In a prospective study with 18 patients, the Cell Saver was used in transoral operations. Blood cultures were taken immediately before retransfusion, 15 min, 2 and 24 h after retransfusion. As a clinical consequence we noticed a higher increase in temperature because of the transient bacteraemia. Other negative clinical consequences were not observed. If adequate antibiotic prophylaxis is used with careful patient selection, we think that the Cell Saver can even be used in transoral operations, although the number of observations is too small to allow definitive conclusions.