Conclusion: We use L as arch length and H as chord length to bend syringe needle that is used to posterior superior alveolar nerve block anesthesia by intraoral injection. The success rate is 98%.

结论：以牙槽孔至颧下嵴起始部的弧长和弦长为标准弯制注射针头，采用口内注射法进行上牙槽后神经阻滞麻醉，成功率为98％。