The Comparative Study Of Alveolar Bone Thickness In The First Molar Area Of The Maxillofacial Mastication Patients

Objective:Researching the effect of lateral mastication on alveolar bone thickness in the bilateral maxillary first molar area of adult patients through CBCT imaging.The study is aimed to provide theoretical basis and guidance for the diagnosis and treatment of orthodontics and micro-implanted anchorage implantation.Methods:47 patients with unilateral mastication habits,who visited the Department of Orthodontics,Stomatology Hospital,Zunyi Medical University from October 2017 to October 2019,were randomly selected,including 19 males and 28 females,aged 18 to 33 years old,with an average age of 24.72 ± 3.99 years old.Before orthodontic surgery,the right cranial radiograph was taken,which was then imported into Uceph(China)software where the FMA value of each experimental subject was measured.The cranial CBCT of patient was taken and imported into NNT viewer software to reconstruct the 3D image.The measurement was conducted in NNT system on the cortical bone thickness,cancellous bone thickness and the total alveolar bone thickness of the buccal palatal side 4mm,7mm under alveolar crest between each U56(between the maxillary first molar and the second premolar);The palatal lateral pitch and total pitch of the maxillary first molars were measured.Statistical analysis used SPSS17.0.Paired t test was used to analyze the difference of alveolar bone thickness between the habitual side and the unaccustomed side in the maxillary first molars.Pearson correlation analysis was used to analyze the alveolar bone and vertical bone profile between maxillary second premolar and first molar.When P< 0.05,the difference was statistically significant.Results:The distribution results for left and right preference of patients with lateral mastication: the left side accounted for 48.9% and the right side accounted for 51.1%.For the difference in the thickness of buccal and palatal bone cortex at 4 mm below the crest of alveolar ridge U56 between the mastication habitual side and the non-habitual side groups,there is no statistical significance(P>0.05);For the difference in the total thickness of the alveolar bone of the buccal and palate side at 4 mm below the crest of alveolar ridge U56 between the mastication habitual side and the non-habitual side groups,there is statistical significance(P<0.05);For the differences in the thickness of the cancellous bone at 4 mm below the crest of alveolar ridge U56 between the mastication habitual side and the non-habitual side groups,there is statistical significance(P<0.05).For the difference in the thickness of buccal and palatal bone cortex at 7 mm below the crest of alveolar ridge U56 between the mastication habitual side and the non-habitual side groups,there is no statistical significance(P>0.05);For the difference in the total thickness of the alveolar bone of the buccal and palate side at 7 mm below the crest of alveolar ridge U56 between the mastication habitual side and the non-habitual side groups,there is statistical significance(P<0.05);For the differences in the thickness of the cancellous bone at 7 mm below the crest of alveolar ridge U56 between the mastication habitual side and the non-habitual side groups,there is statistical significance(P<0.05).For the difference between the maxillary first molar root apical palatal lateral alveolar bone of the mastication habitual side and the non-habitual side,there is statistical significance(P<0.05);For the difference in the total thickness of the maxillary first molar lateral palatal lateral alveolar bone of the mastication habitual side and the non-habitual side,there is statistical significance(P<0.05);There is no linear correlation between FMA and the total thickness of alveolar bone at the buccal and palatal side at 4mm and 7 mm below the crest of alveolar ridge U56(P>0.05).Conclusion: In patients with lateral chewing,the thickness of the maxillary first molar and the second premolar between the buccal and palate toward the alveolar bone and the thickness of the cancellous bone.The chewing habitual side is thicker than the non-habitual side.It is higher than the non-masticatory side.The alveolar bone at the apex of the palatal root of the first molar of the maxillary is thicker than the non-habitual side of the chewing habit.The risk is smaller than the unaccustomed side.