Evaluation of changes in nasal profile after Lefort 1 osteotomy (maxillary advancement) with and without ANS reduction in class III skeletal patients referred to Buali and Farhikhtegan Hospital in Tehran in 1400 and 1401: A Randomized Clinical Trial

Evaluation of changes in nasal profile after Lefort 1 osteotomy (maxillary advancement) With and without ANS reduction in skeletal patients of class III referred to Bouali and Farhikhtegan hospitals in Tehran in 1400 and 1401

From the patients referred to the maxillofacial clinic, 26 class III skeletal patients are selected and randomly using balance block randomization with a sample size inside each block equal to 4 samples and random allocation inside the samples equally from both groups with the help of Rand software and Excell software are divided into two groups. The result of random allocation is done by a person other than the surgeon and evaluator and the type of allocation treatment is recorded on paper and for each sample is placed in a separate package with the sample sequential code. When surgery is performed with clinicians, they do not know the outcome of the allocation process in each sample until that moment.

pre-op lateral cephalometry is done and the analysis of study points and angles will be performed. On the day of surgery, two sets are prepared according to the two types of study intervention, and at that time, the envelope is opened according to the patient's assigned code, and the type of intervention. After 3 months, lateral cephalometry is requested from the same radiology center in the same position as before.

No history of maxillofacial surgery and need at least 3 mm maxillary advancemeny. Contrary to the mentioned conditions causes the patient to leave the study

Intervention: For these people, Lefort 1 surgery is performed with maxillary ANS reduction Control: For Irene patients, Lefort 1 surgery is performed without maxillary ANS reduction. ANS: Anterior nasal spine

Nasolabial angle and upper lip length

Patients are randomly divided into two groups using balanced block randomization with a sample size of 4 samples in each block and random allocation of samples in both groups with the help of Rand software, Excell software. The result of random allocation is done by a person other than the surgeon and evaluator (consultant of methodology and study statistics) and the type of allocation treatment is recorded on paper and each sample is placed in a separate package with a sample order code. When surgery is performed, clinicians who do not know the outcome of the allocation process in each sample until the time of surgery will open the packages.

The result of random allocation is done by a person other than the surgeon and evaluator (consultant of methodology and study statistics) and the type of allocation treatment is recorded on paper and each sample is placed in a separate package with a sample order code. When surgery is performed, clinicians who do not know the outcome of the allocation process in each sample until the time of surgery will open the packages.