OBJECTIVETo determine the role of 1,25(OH)2D3 on the secondary dentin formation and mineralization of the mice.

METHODSThe differences of the mandible mineralization between the wild-type and 1-alpha-hydroxylase gene knockout mice at 6 weeks old were assessed by hematoxylin-eosin (HE) staining, immunohistochemistry, alkaline phosphatase (ALP) histochemistry staining.

RESULTSThe ratio of caries were increased significantly, while the secondary dentin was reduced significantly, the deposition of type I collagen and osteocalcin on the secondary dentin of occlusion surface was decreased significantly, but the deposition of the Biglycan on the dentin was increased significantly, the active of ALP on the odontoblasts were reduced significantly in 1-alpha-hydroxylase gene knockout mice compared to that in the wild-type littermates.

CONCLUSION1,25(OH)2D3 deficiency lead to a defect in the secondary dentin formation and mineralization and caries of the mice.

Animals ; Dentin ; Dentin, Secondary ; Mandible ; Mice ; Osteocalcin

OBJECTIVETo explore the influence of proximal-tip location on partial necrosis in distally based sural neuro fasciocutaneous flap.

METHODSFrom April 2001 to May 2009,157 distally based sural neuro fasciocutaneous flaps were conducted to repair the soft tissue defect in distal region of lower leg, ankle and feet in 153 patients. Date of the flaps and the patients were retrospectively analyzed. From the tip of lateral malleolus to the popliteal crease, posterior aspect of the lower leg was equally divided into 9 regions that were 1st to 9th region from inferiorly to superiorly, respectively. The flaps were divided into 2 groups: survival group (including uneventfully survived flaps, flaps with distally epidermal necrosis and with wound dehiscence) and partial necrosis group. Based on the location of the proximal tip of flaps, the flaps were stratified into 4 groups: flaps with the proximal tip locating in the 6th or lower region (group A), the 7th region (group B), the 8th region (group C) and the 9th region (group D). Harvesting the flaps started from exploring the perforator of peroneal vessel in the adipofascial pedicle, then the flaps were elevated retrogradely.

RESULTSOf the 157 flaps, 125 survived uneventfully,8 showed distal epidermal necrosis,wound dehiscence occurred in 6 flaps, 18 flaps (11.5%) showed distal partial necrosis. Partial necrosis occurred in zero of 19 flaps in group A (0), 1 of 44 flaps in group B (2.3% ), 7 of 62 flaps in group C (11.3% ) and 10 of 32 flaps in group D (31.3% ). The differences in partial necrosis rate between group A and group B , group B and group C, were not statistically significant (P > 0.05). Partial necrosis rate was higher in group D than in group C (P = 0.012), it was lower in group A + group B (1.6%) than in group C + group D (18. 1% ) (P = 0. 001).

CONCLUSIONSDistally based sural neuro fasciocutaneous flap can survive reliably when the proximal tip of flap is not beyond the junction between lower 7/9 and upper 2/9 of the lower leg, whereas probability of partial necrosis occurring in the flap increase significantly when the proximal tip of flap locates in upper 1/9 of the lower leg.

Adolescent ; Adult ; Aged ; Child ; Child, Preschool ; Female ; Follow-Up Studies ; Humans ; Leg Injuries ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Soft Tissue Injuries ; surgery ; Sural Nerve ; Surgical Flaps ; Treatment Outcome ; Young Adult