Pattern of third molar impaction in a Singapore Chinese population: a retrospective radiographic survey

One thousand orthopantomograms (OPGs) of patients 20-40 years old were examined. Where impacted third molars were present, the angle and depth of impaction were recorded. Results were analysed using the Pearson chi2 test. 68.6% of OPGs showed at least one impacted third molar. The frequency was three-fold higher in the mandible (1024/1079=90%) than in the maxilla (306/1077=28%), with a significantly higher frequency (P<0.05) in females (56%) than males (44%). The mesioangular impaction was the most common, and 80% of all impacted third molars were partially buried in bone. Of the 429 bilateral occurrence of impacted third molars, 423 were in the mandible. It was concluded that the frequency of impacted third molars in the Singapore Chinese population studied was generally two to three times that reported in races of the Caucasian stock. There was also double the frequency of impacted third molars when compared to a previous study in a Chinese population published in 1932 with females being more frequently affected than males.

Application of Kuntscher Y nailing for fractures involving upper end of femur

Kuntscher Y nail is biomechanically a stable assembly and is useful in the management of unstable intertrochanteric, subtrochanteric and pathological fractures involving the upper end of the femur. In addition, it was ideal in special situations with fracture of the upper end of the femur; in a mentally ill patient with an unstable trochanteric fracture, for non-union of a trochanteric fracture and for a fracture of the upper end of the femur associated with a fracture further distally of the femoral shaft. Although it proved to be a very stable fixation, the control of external rotation of the distal femoral shaft was a significant problem in two cases. In all six cases stable fixation was achieved which progressed to sound union, including the case with ununited fracture. No technical difficulty was encountered at the time of operation although this could pose a significant problem. The main danger is the splintering of the lateral subtrochanteric femoral cortex during insertion of the neck piece and inability to negotiate the Kuntscher nail through the fenestration in the neck piece.

Fracture of the odontoid process

A review of 26 cases of odontoid fractures has been carried out. Late diagnosis and consequent delay in treatment were found to be important causes of non-union. Myelopathy in odontoid fractures is of two types. One type is that present immediately after injury, while the other is delayed. In treatment of long-standing cases, only fusion without posterior decompression should be done. If the latter procedure is carried out, it can produce medullospinal haematomyelia with respiratory arrest and tetraplegia. In the performance of atlanto-axial fusion, the technique of bone grafting and the use of thick wires need emphasis.