[Application of three dimensional model in evaluating the effect of artificial bone implantation of hard cleft palate on the development of maxilla]

OBJECTIVE

To observe the effect of artificial bone implantation of hard cleft palate on the development of maxilla.

METHODS

From January 1997 to December 1999, 40 patients with hard cleft palate were randomly divided into two groups: control group and implantation group (n = 20 each). The patients in the implantation group received an implantation of compound artificial bone of HA-Bone cement. All patients had a follow-up since 16 years old. A three dimensional model was established with computed tomography and rapid prototype technique to analyze the maxilla in three dimension. At the same time, a dentognathic model was employed.

RESULTS

There were no differences in the results between the three dimensional and dentognathic models. No difference was found in the development of maxilla in length and height between the control and implantation groups. There were marked differences in the development of maxilla in width between two groups (67.6 mm ± 4.3 mm vs 61.3 mm ± 4.1 mm, 63.5 mm ± 3.9 mm vs 57.3 mm ± 3.1 mm, 26.2 mm ± 1.8 mm vs 26.4 mm ± 1.9 mm, all P < 0.05). The width of maxilla in the implantation group was markedly wider than that in the control group.

CONCLUSIONS

The application of three dimensional model for evaluating the development of maxilla is both straightforward and accurate. Bone implantation of hard cleft palate is an obvious boost to the development of maxilla in width. It should be included into a comprehensive orthodontic treatment for patients with hard cleft palate.

[Soft tissue profile changes in micrognathia after distraction osteogenesis]

OBJECTIVE

To evaluate the effect of distraction osteogenesis for severe micrognathia by comparing the pre- and post-operative profile and mentolabial relationship.

METHODS

16 cases underwent temporal-mandibular joint plasty and temporal fasciomuscular flap transfer. The mandibular distraction began at the 5th postoperative day at a rate of 0.8 mm a day, two times a day. Bony and soft tissue cephalometry were performed before and after operation. T-test was used to study the change after distraction osteogenesis.

RESULTS

There were significant differences in facial convexity, lower facial height, lower lip length, inter-labial distance, the ratio of lip to mental, the distance from lip to esthetic plane, the depth of mentolabial crease and the thickness of mental soft tissue.

CONCLUSIONS

Mandibular distraction osteogenesis can markedly improve the soft tissue profile of the middle and lower face for severe micrognathia.

[Report of 10 cases of multiple myeloma surviving more than 6 years]

Ten cases of multiple myeloma seen in PUMC hospital survived more than six years. 4 of them survived more than ten years. 6 patients were of IgA type. Features of those cases included: (1) symptoms mild; (2) incidence of anemia low; (3) percentage of tumor cell in bone marrow also relatively low; (4) blood urea nitrogen, creatinine and calcium normal; (5) maintenance therapy rather long. The prognostic factors and the current general situation of treatment were briefly discussed.

[Leukemia and solid tumor]

3 cases of leukemia after solid tumor and 2 cases of solid tumors after leukemia were reported. The features of leukemia after solid tumor and the relationship between the solid tumor and leukemia, as well as the possible pathogenetic factors of the secondary malignancies were discussed.

[Hemochromatosis: a review of 22 Chinese cases]

22 cases of hemochromatosis were analysed. 19 cases were collected from Chinese medical journals and 3 from our hospital. We showed the similarities and differences between Chinese and western patients. The diagnosis, mode of heredity, possible pathogenesis and management of idiopathic hemochromatosis were also briefly discussed.

[Various transformations of polycythemia vera]

90 cases of polycythemia vera (PV) were diagnosed and followed up more than 3 years in PUMC Hospital from 1957 to 1986. 15 cases (16.7%) had various transformations during their courses. 4 cases had more than one kind of transformation. As a rare event, one case transformed to chronic lymphocytic leukemia. For illustration, some typical cases were presented, and the related fetuses discussed.