Forty sandwich osteotomies in atrophic mandibles: a retrospective study.

PURPOSE: The aim of the present retrospective study was to assess the suitability of segmental mandibular sandwich osteotomy combined with an interpositional autograft to meet the dimensional requirements of preimplant bone augmentation in cases of a severely atrophic mandible. PATIENTS AND METHODS: A total of 27 consecutive patients (6 men and 21 women) were included in the present study. The amount of bone gain was calculated using digital volume tomography before surgery and 3 months after bone augmentation. RESULTS: The postoperative course was uneventful for 18 patients. Temporary sensory disturbances were observed in 6 patients, with complete recovery after 3 to 12 weeks. Dehiscence of soft tissue closure occurred in 3 patients. The mean vertical gain was 3.41 mm (range 0.3 to 12). The mean horizontal gain was 3.08 mm (range 0.2 to 8.5). A total of 88 implants were placed in 40 surgical sites at 12 weeks after bone reconstruction. CONCLUSION: Segmental mandibular sandwich osteotomy is a suitable augmentation procedure in the mandible for the atrophic alveolar ridge and provides adequate height and transversal bone augmentation.

A preliminary report about treatment of bisphosphonate related osteonecrosis of the jaw with Er:YAG laser ablation.

BACKGROUND AND OBJECTIVES: This preliminary report describes a new laser-assisted treatment option for the emerging complication of bisphosphonate related osteonecrosis (BON) of the jaw. MATERIALS AND METHODS: In eight tumour patients (three women, five men) ten bony lesions in the maxilla and mandible in the course of intravenous bisphosphonate therapy were treated with a variable square pulsed (VSP) Er:YAG laser. For the treatment, the Er:YAG laser was applied with a pulse energy of 1,000 mJ, a pulse duration of 300 microseconds, and a frequency of 12 Hz (energy density 157 J/cm(2)). The spot size was 0.9 mm and the handpiece was kept at a distance of about 10 mm from the bone surface. The diseased bone was ablated exclusively with the Er:YAG laser by subsequently sweeping the bone surface in a well directed scanning mode. RESULTS: The surgical procedure and postoperative wound healing were without any complications and a complete soft tissue recovering was achieved within 4 weeks. During follow-up examinations over 12 months soft tissue conditions were stable. The pulsed laser ablation caused a characteristic microstructured and craggy bone surface without a condensation or a smear layer on the laser rims. CONCLUSION: The bone ablation technique using a VSP Er:YAG laser yielded promising clinical results without impairment of wound healing. A further analyse of the chemical, physical and pharmacological aspects of laser assisted treatment of BON lesions is necessary to get a safe and reliable treatment protocol for bisphosphonate-related osteonecrosis of the jaw.

Keratinocyte-derived vascular endothelial growth factor biosynthesis represents a pleiotropic side effect of peroxisome proliferator-activated receptor-gamma agonist troglitazone but not rosiglitazone and involves activation of p38 mitogen-activated protein kinase: implications for diabetes-impaired skin repair.

The peroxisome proliferator-activated receptors (PPARs) represent pharmacological target molecules to improve insulin resistance in type 2 diabetes mellitus. Here we assessed a functional connection between pharmacological activation of PPAR and vascular endothelial growth factor (VEGF) expression in keratinocytes and during diabetes-impaired acute skin repair in obese/obese (ob/ob) mice. PPARbeta/delta agonist 4-[3-[4-acetyl-3-hydroxy-2-propylphenoxy)propoxy]phenoxy]acetic acid (L165,041) and PPARgamma agonists ciglitazone and troglitazone, but not rosiglitazone, potently induced VEGF mRNA and protein expression from cultured keratinocytes. Inhibitor studies revealed a strong functional dependence of troglitazone- and L165,041-induced VEGF expression on p38 and p42/44 mitogen-activated protein kinase (MAPK) activation in keratinocytes. Rosiglitazone also induced activation of p38 MAPK but failed to mediate the activation of p42/44 MAPK in the cells. Functional ablation of PPARbeta/delta and PPARgamma from keratinocytes by small interfering RNA did not abrogate L165,041- and troglitazone-induced VEGF biosynthesis and suggested VEGF induction as a pleiotropic, PPAR-independent effect of both drugs in the cells. In accordance with the in vitro situation, we found activated p38 MAPK in wound keratinocytes from acute wounds of rosiglitazone- and troglitazone-treated diabetic obese/obese mice, whereas keratinocyte-specific VEGF protein signals were only prominent upon troglitazone treatment. In summary, our data from cell culture and wound healing experiments suggested p38 MAPK activation as a side effect of thiazolidinediones; however, only troglitazone, but not rosiglitazone, seemed to translate p38 MAPK activation into a PPARgamma-independent induction of VEGF from keratinocytes.

[First experiences in maxillary arch expansion using the MWD (Maxillary Widening Device)]. / Erste Erfahrungen mit dem "Maxilla Widening Device" (MWD) zur Expansion des Oberkiefers.

AIM: Conventional devices for surgical assisted rapid palatinal expansion are either tooth or bone borne. During clinical application over years, system dependant deficiencies, using either device became apparent. So together with Normed, Tuttlingen, we developed a new bone borne distractor (MWD, Maxillary Widening Device). In this article we introduce this distractor and present our first experiences in using this device. PATIENTS AND METHODS: In this study, 20 patients suffering from maxillary arch compression with anterior crowding were treated using MWD in combination with Glassman's modified Le-Fort-I-osteotomy. Additionally the MWD was inserted in two cleft lip and palate patients, as well as one patient with bilateral microsomy. RESULTS: The MWD turned out to be a safe, easy to handle and reliable bone borne distractor leading to excellent results. The MWD can be used in early adult as well as in syndromal patients. In early adult patients the complication rate averaged 25%, widening averaged 7,6mm. Relaps was not discovered. CONCLUSION: The MWD turned out to be a reliable, stable and user-friendly device leading to excellent results.