Dasgupta P, Kamath G, Hs S, Babshet M, Doddamani L
Department of oral medicine and radiology, Sri Hasanamba Dental College and hospital, Pin- 573202, Hassan, Karnataka, India.
Department of oral medicine and radiology, Sri Hasanamba Dental College and hospital, Pin- 573202, Hassan, Karnataka, India.
J Stomatol Oral Maxillofac Surg. 2017 Dec;118(6):337-341. doi: 10.1016/j.jormas.2017.06.018. Epub 2017 Jul 8.
Median maxillary labial frenum (MMLF) appears as a fold of mucous membrane extending from the lining of the mucous membrane of the lips towards the crest of the alveolar ridge on the labial surface. MMLF can demonstrate certain variations in their shape, size and position, both among individuals and within the same individual at different ages. Many clinicians, not being aware of the normal variations of median maxillary labial frenum misinterpret them as pathological entities.
The objectives of the study were to determine the prevalence of morphologic variations of MMLF, to classify the morphological variations of MMLF on the basis of their location on the frenum and to compare the morphological variations of MMLF among different age groups and genders.
The study was conducted on 700 males and 700 females of age 5 to 74 yrs, chosen randomly. They were equally divided on the basis of age into 7 groups, each group having equal gender distribution. The morphological variations of MMLF were classified according to Sewerin's classification and the attachments on the freni were further sub-classified.
The commonest type of frenum was found to be the simple type, whereas bifid frenum was not found at all. Statistically significant difference was found in proportion of types of frenum among the different age groups and also in proportion of types of frenum among the different sites of presence of frenal attachments. No statistically significant difference was found in proportion of types of frenum in male and female subjects.
This study shows that MMLF presents with an array of morphological variations. These morphological variations may sometimes pose a complicating factor in maintaining oral hygiene, speech, mastication, esthetics, denture construction, etc. Hence, appropriate recognition of frenal variations and subsequent modification of treatment procedures are essential for a successful outcome of therapy.
上颌中切牙唇侧正中系带（MMLF）表现为一层黏膜皱襞，从唇黏膜内衬延伸至唇侧牙槽嵴顶。MMLF在形状、大小和位置上存在个体差异，且同一个体在不同年龄阶段也会有所变化。许多临床医生不了解上颌中切牙唇侧正中系带的正常变异，将其误判为病理情况。
本研究旨在确定MMLF形态变异的发生率，根据系带位置对MMLF的形态变异进行分类，并比较不同年龄组和性别的MMLF形态变异情况。
本研究随机选取了700名年龄在5至74岁之间的男性和700名女性。根据年龄将他们平均分为7组，每组性别分布均衡。MMLF的形态变异按照Sewerin分类法进行分类，系带附着情况进一步细分。
最常见的系带类型为简单型，未发现双叉系带。不同年龄组之间以及系带附着不同部位之间的系带类型比例存在统计学显著差异。男性和女性受试者的系带类型比例未发现统计学显著差异。
本研究表明，MMLF存在一系列形态变异。这些形态变异有时可能会在保持口腔卫生、言语、咀嚼、美观、义齿修复等方面成为一个复杂因素。因此，正确识别系带变异并相应调整治疗程序对于治疗的成功至关重要。
