|Year : 2016 | Volume
| Issue : 3 | Page : 320-323
Variations in the frenal morphology in the diverse population: A clinical study
Vikas Jindal, Rupinder Kaur, Amit Goel, Atika Mahajan, Neha Mahajan, Atin Mahajan
Department of Periodontology and Implantology, Himachal Dental College, Sundernagar, Himachal Pradesh, India
|Date of Submission||14-Mar-2015|
|Date of Acceptance||05-Apr-2016|
|Date of Web Publication||4-Jul-2016|
Department of Periodontology and Implantology, Himachal Dental College, Sundernagar, Himachal Pradesh
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: The upper labial frenum is a normal anatomic structure with inherent morphological variations. Frenum has variations depending upon the attachment of fibers along with the presence of structural variations. Aim: The aim of this study was to evaluate the prevalence of frenal variations in a diverse ethnic population of Sundernagar, Himachal Pradesh. Materials and Methods: This study was conducted on 500 subjects within age group of 16–40 years (285 females, 215 males). Intraoral examination was done to evaluate the variations in frenum and photographs were taken. Results: In this study, depending upon structural variations, normal frenum was most common followed by frenum with nodule while frenum with appendix was found to be least common. However, no significant difference was found between males and females (P > 0.05) with respect to all frenal attachments. Furthermore, other structural variations were found in the diverse population of Sundernagar, Himachal Pradesh. Conclusion: Upper labial frenum is a small anatomical landmark in the oral cavity found to have diverse morphology. The dentist needs to give due importance for frenum assessment during the oral examination.
Keywords: Frenal attachment, frenum, papillary penetrating
|How to cite this article:|
Jindal V, Kaur R, Goel A, Mahajan A, Mahajan N, Mahajan A. Variations in the frenal morphology in the diverse population: A clinical study. J Indian Soc Periodontol 2016;20:320-3
|How to cite this URL:|
Jindal V, Kaur R, Goel A, Mahajan A, Mahajan N, Mahajan A. Variations in the frenal morphology in the diverse population: A clinical study. J Indian Soc Periodontol [serial online] 2016 [cited 2021 Aug 3];20:320-3. Available from: https://www.jisponline.com/text.asp?2016/20/3/320/182598
| Introduction|| |
Frenum is one of the most variable anatomical structures present in the oral cavity which can be defined as a “fibrous band of tissue attached to the bone of the mandible and maxillae, and is present superficial to muscle attachments.” Frena are mostly seen in the vestibular mucosa of the mandible and maxilla, usually in the midline or premolar region. The maxillary/mandibular labial frena and the lingual frena are the most notable frenum of the normal oral cavity. Among all the other frena, maxillary frena are a dynamic structure that is subjected to variations during different stages of human growth and development.
The upper labial frenum is a small, sickle-shaped mucosal fold extending from the vestibular mucosa of the upper lip to the alveolar or gingival mucosa in the anterior midline of the maxillary arc. Histologically, it is made up of loose fibrous connective tissue, abundance of elastic fibers along with a few striated muscle fibers that arise from the muscle bundles of the lip on either side of the midline; however, the controversy regarding the histology of frenum still remains., The primary function is to provide stability to the upper lip, lower lip, and tongue. Similar to other body parts, upper labial frenum has demonstrated variations and anomalies depending on the attachment of fibers and structure of frenum.
A high frenal attachment can become a noteworthy problem if tension from lip movement pulls the gingival margin away from the tooth, or if the tissue restrains the closure of a diastema during orthodontic treatment. Frenal attachments that encroach on the marginal gingiva distend the gingival sulcus thus, promoting plaque accumulation, increasing the rate of progression of periodontal recession and thus leading to recurrence after treatment. Various classifications have been proposed regarding the variations in frenum, but the most widely accepted classifications were given by Mirko et al., and Sewerin.
Depending upon the extension of attachment of fibers, frena have been classified as:
- Mucosal – when the frenal fibers are attached up to mucogingival junction
- Gingival – when fibers are inserted within attached gingiva
- Papillary – When fibers are extending into interdental papilla
- Papilla penetrating – When the frenal fibers cross the alveolar process and extend up to palatine papilla.
Sewerin  has also classified the variations of frenum as:
- Normal frenum
- Normal frenum with a nodule
- Normal frenum with appendix
- Normal frenum with nichum
- Bifid labial frenum
- Persistent tectolabial frenum
- Double frenum
- Wider frenum.
However, relatively few studies have been documented pertaining to the prevalence and types of the maxillary labial frenum. Thus, the aim of this study was to evaluate the prevalence of frenal variations in a diverse ethnic population in Sundernagar, Himachal Pradesh.
| Materials and Methods|| |
The sample consisted of 500 subjects comprising both males and females within the age group of 16–40 years who visited the outpatient department of Himachal Dental College, Sundernagar, Himachal Pradesh. The study protocol was duly reviewed and approved from the Institutional Ethical Committee. All the subjects were explained about the study, and a written informed consent was obtained from all the subjects. The subjects who had undergone an operation on upper labial frenum, any trauma or injury to the mucosa of maxillary incisors region, any congenital/developmental abnormality in upper frenum or premaxilla, and one or both maxillary central incisors missing were excluded from the study.
The examination of frenum was done by upward distention of the upper lip following which photographs were taken of the variations of frenum if present. The data thus collected were subjected to statistical analysis.
The Chi-square test was used for the statistical analysis.
| Results|| |
In this study, following results were observed.
According to the classification by Mirko et al., in this study, 66.0% the patients presented with mucosal type of frenal attachment while in 28.4% of the patients, gingival type was seen. Least common type of attachment was papillary type found only in 2.4% of patients, and papillary penetrating was found only in 3.2% of patients as seen [Table 1].
The gender-based variations were found to be more prevalent in females in relation to mucosal, gingival, and papillary type (66.6%, 28.40%, and 2.80%) as compared to males (65.11%, 27.90%, and 2.32%), respectively. Type of frenal attachment is more prevalent in females (66.6%) than males (65.11%). Only difference was seen in papillary penetrating which was more prevalent in males (4.65%) as compared to females (2.10%), as seen in [Table 1]. However, no significant difference was found between males and females (P > 0.05) in relation to all attachments.
The prevalence of midline diastema was found to be more in the papillary penetrating type of frenal attachment (62.5%) as compared to papillary (33.3%) and gingival attachment (1.40%) as seen in [Table 1].
According to the classification by Sewerin, in this study, 77.6% of patients had regular, falciform fold (normal frenum) while in 12.4% of patients, there is a nodule present in frenum (frenum with nodule). In 9.0% of patients, there was presence of appendix in frenum (frenum with appendix) while all other forms were absent in this study as seen in [Table 2].
The gender-based variations were found to be more prevalent in females in relation to simple frenum, frenum with nodule, and frenum with appendix (85.11%, 15.43%, and 11.22%) as compared to males (71.92%, 8.37%, and 6.04%), respectively, as seen in [Table 2]. This high frequency in females is statistically significant (P < 0.05).
Other structural variations which were seen apart from Sewerin  classification are as depicted in [Figure 1] and [Table 3].
|Figure 1: Morphological variations of frenum seen in the study. (a) Double frenum with appendix; (b) Double frenum with nodule; (c) Multiple frenum; (d) Nodule with appendix; (e) Multiple frenum with appendix|
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|Table 3: Prevalence of other variations found in diverse ethnic population|
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| Discussion|| |
Various conditions of the oral cavity that does not require any treatment include fordyces granules, leukoedema, fissured tongue, retrocuspid papilla, and the inherent morphologic variations associated with upper labial frenum. Upper labial frenum is a fold of mucous membrane extending from the mucous lining of the mucous membrane of the upper lip toward the crest of residual ridge on the labial surface. The primary maxillary function of frenum is to provide stability to the upper lip.
The clinical implications related to frenal anomalies such as difficulties in speech, mastication, esthetics, and maintenance of oral hygiene constituting a periodontal problem have been well documented in the literature., If labial frenal attachment is inserted at or near the gingival margin, it interferes with tooth brushing and encourages plaque formation by pulling or averting the gingival margin. Any developmental or acquired defect in the underlying labial bone margin along with high frenal pull may contribute to the initiation and progression of the gingival recession. It has also been proposed that labial frenum should be carefully examined as it may serve as potential cofactor for peri-mucositis and peri-implantitis.,
The presence of abnormal frenal attachment has been reported in the literature as a feature of various syndromic conditions such as Turner, Ellis–van Creveld syndrome, Oro-facial-digital syndrome, Ehler–Danlos syndrome, and Pallister–Hall syndrome. Upper labial frenum has also been considered to be a modifying factor in denture construction. Abnormal frenal variations with a broad base migrated near the crest of the residual ridge; these require early recognition and surgical removal for a more satisfactory treatment outcome with complete dentures.
As suggested in literature, there are several variations found in upper labial frenum. These variations can be classified according to attachment of fibers of frenum or can be structural variations in frenum. It has been considered that papillary and papilla penetrating frena are pathologic., In a study done by Mirko et al., it was proposed that different type of frenal attachment influences the periodontal condition with gingival, papillary, and papilla penetrating types of maxillary frenal attachments showing lower periodontal resistance in persons with pathologic changes as compared to healthy persons with similar frenal attachment.
There are very few studies that have been published pertaining to the type of the upper labial frenum and its prevalence. This study was conducted on 500 subjects in the Himachal Dental College, Sundernagar, Himachal Pradesh. To our present knowledge, this is the first study regarding the prevalence of variations in upper labial frenum in the diverse population of Sundernagar, Himachal Pradesh.
In this study, the prevalence of mucosal frenal attachment was found to be most common (66.0%) with gingival frenal attachment as second (28.4%) followed by papillary penetrating (3.2%) with papillary type (2.40%) least common. In the similar study done by Mirko et al., the prevalence was found to be as mucosal (46.6%), gingival (34.3%), papillary (3.1%), and papillary penetrating (16.1%). The difference in results in this study as compared to Mirko et al., could be due to the diversity of population. In gender-based comparison, no statistically significant difference was found which was similar to the study done by Townsend et al.
During development, the failure of the frenum to migrate apically has been implicated as the causative factor in the persistence of the midline diastema. It may be caused by the insertion of the labial frenum into the notch in the alveolar bone so that a band of heavy fibrous tissue lies between the central incisors. In this study, the prevalence of midline diastema was found to be more in papillary penetrating type of frenal attachment as compared to papillary and gingival attachment. Similar results were observed in a study done by Mirko et al., who found that midline diastema was more prevalent in the papillary penetrating type of frenal attachment.
Various studies have found difference in the structural variations of the frenum. Sewerin  had classified structural variations in frenum. In this study, most commonly observed frenum was the normal frenum (77.60%). Similar results were seen in the studies done by Townsend et al., who reported the prevalence of normal frenum as 68.64% while Mohan et al., reported 66.21% prevalence of upper labial frenum. In a similar study done by Sewerin, the prevalence of normal frenum of 60.2% was reported.
In this study, the prevalence of normal frenum with nodule was 12.41%, which was reported to be 9.1% in a study done by Sewerin, 17.42% in the study by Townsend et al., and 19.92% was reported by Mohan et al. Normal frenum with appendix had a prevalence of 9.0% in this study, which was reported to be 19.9% in a study by Sewerin, 10.45% in the study by Townsend et al., and 6.38% in a study of Mohan et al. In this study, there was statistically significant higher frequency of variations in females compared to males. However, in the study done by Sewerin, the frequency of variations was higher in males as compared to females. There was absence of other variations seen by Sewerin  such as normal frenum with nichum, bifid labial frenum, persistent tectolabial frenum, double frenum, and wider frenum.
Other variations apart from Mirko  and Sewerin  were also observed during this study. These included such as double frenum with appendix, double frenum with nodule, multiple frenum, nodule with appendix, and multiple frenum with appendix [Figure 1]. In these variations, no statistically significant difference was found between males and females. No reports are available in literature for the other variations reported.
Hence, proper identification of various frenal variations and subsequent modification of treatment procedures are vital for a successful outcome. The dentist needs to give due importance for frenum assessment during oral examination.
| Conclusion|| |
To conclude, various reports of frenal anomalies causing difficulties in speech, mastication, and aesthetics have already been discussed in the literature. These abnormalities of maxillary frenum have also been associated with various syndromes. In summary, it is apparent that that proper identification of various frenal variations are important and need to be addressed. The dentist thus needs to give due importance for frenum assessment during oral examination.
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Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3]