|
|
 |
|
ORIGINAL ARTICLE |
|
Year : 2019 | Volume
: 7
| Issue : 3 | Page : 65-70 |
|
Evaluation and comparison of freeway space in edentulous and dentulous patients with and without head-stabilizing device
Khushboo Mishra, Divya Hegde, Suchitra SR, Sajan Shetty, Sanjana Shah, Alwin George
Department of Prosthodontics, Bangalore Institute of Dental Sciences, Bengaluru, Karnataka, India
Date of Submission | 17-Oct-2019 |
Date of Acceptance | 17-Oct-2019 |
Date of Web Publication | 19-Nov-2019 |
Correspondence Address: Dr. Khushboo Mishra Department of Prosthodontics, Bangalore Institute of Dental Sciences, Bengaluru, Karnataka. India
 Source of Support: None, Conflict of Interest: None
DOI: 10.4103/INJO.INJO_35_19
Objectives: The purpose of this study was to compare and evaluate freeway space with and without head-stabilizing device. Materials and Methods: A head posture-fixing device was used to fix the head posture in a natural head position. The goniometer (ISICO, 17 Transparent, 360°, Galaxy informatics India, Karol Bagh, New Delhi-India) axis was used in various studies to standardize head posture changes. The digital calipers with measuring range of 0–150 mm/0”–6” and resolution of 0.01 mm/0.0005” was used. Chin–tip of the nose (Niswonger’s method) was taken as the reference point. Results: Freeway space without head-stabilizing device for dentulous and edentulous subjects was 4.8 mm and with stabilizing device was 2.2 mm, which was near to the precise value, and was found to be significant with head-stabilizing device. Conclusion: There was a significant difference between all tested groups. These results clarified that freeway space with head-stabilizing device obtained excellent reproducibility compared to the conventional methods. Keywords: Complete dentures, face height, freeway space, reliability, vertical dimension
How to cite this article: Mishra K, Hegde D, SR S, Shetty S, Shah S, George A. Evaluation and comparison of freeway space in edentulous and dentulous patients with and without head-stabilizing device. Int J Oral Care Res 2019;7:65-70 |
How to cite this URL: Mishra K, Hegde D, SR S, Shetty S, Shah S, George A. Evaluation and comparison of freeway space in edentulous and dentulous patients with and without head-stabilizing device. Int J Oral Care Res [serial online] 2019 [cited 2023 Mar 25];7:65-70. Available from: https://www.ijocr.org/text.asp?2019/7/3/65/271309 |
Introduction | |  |
The determination of interocclusal relationship in the correct mandibular position is important to provide dental treatments that fit stomatognathic system in patients with multiple tooth loss, edentulous jaw, and loss of occlusal dimension. The physiologic rest position of the mandible is widely used in clinical practice as a functional method for the determination of occlusal vertical dimension. However, the mandibular position is considered to be affected by various factors such as head and body postures and mental state as well as masticatory and facial muscles and temporomandibular joints.[1] As the head is bent forward, the closing path approached the maximum intercuspal position from the anterior region, and as the head is bent backward, the closing path approached the maximum intercuspal position from the posterior region.[2] There is an effect of gravity on a forward head posture, which causes an increase in forward tension, which induces fatigue and presents a compressive force on the soft tissue. The freeway space is now generally recognized as a normal and necessary feature of normal occlusal function.[3] When selecting the best method to use, criteria to be considered are accuracy and repeatability of the measurement, adaptability of the technique, type and complexity of the equipment needed, and the length of time required to secure the measurement.[4] The incorrect measurement and resultant provision of insufficient freeway space have been reported to lead to teeth clashing, with difficulties approximating the lips, with discomfort brought about by constant stimulation of the muscles, poor appearance, cheek biting, angular cheilitis, temporomandibular joint pain, Costen’s syndrome, and masticatory inefficiency.[5] This study was proposed to evaluate and compare freeway space with and without head-stabilizing device.
Materials and Methods | |  |
A head posture-fixing device modified in the Department of Prosthodontics, Bangalore Institute of Dental Sciences, Bengaluru, Karnataka, India, was used to fix the head posture in a natural head position. This device consists of an earpiece to stabilize the auricles, one movable vertical arm, headrest, and Velcro strap to stabilize the head. The goniometer (ISICO, Transparent, 360°, Karol Bagh, New Delhi, India) axis is used to cross-check whether the position is correct or not. It is centered over the external acoustic meatus, the fixed arm is held vertical, whereas the movable arm is aligned with the meatus-to-base of nares reference line to check the head position, and moreover it has been used in various studies to standardize head posture changes. The digital calipers with measuring range of 0–150 mm/0”–6” and resolution of 0.01 mm/0.0005” was used. Chin–tip of nose (Niswonger’s method) was taken as the reference point.
With head-stabilizing device
A head posture-fixing device modified in our department was used to fix the head posture in a natural head position. This device consists of earpiece to stabilize the auricles, one movable vertical arm and one fixed arm, headrest, and Velcro strap to stabilize the head. The goniometer axis was used to cross-check whether the position is correct or not. It was centered over the external acoustic meatus, the fixed arm was held vertical, whereas the movable arm was aligned with the meatus-to-base of nares reference line to check the head position; and it has been used in various studies to standardize head posture changes [Figure 1] and [Figure 2]. The digital calipers with measuring range of 0–150 mm/0”–6” and resolution of 0.01 mm/0.0005” was used to measure the freeway space. Tapes were applied on the points of nose and chin, and circles of approximately 0.3 mm in diameter were marked on these tapes. The tips of the calipers were placed in the center of these marks during measurements of the distance between nose and chin. The measurement of vertical dimension at rest and vertical dimension at occlusion was recorded by vernier caliper, and then freeway space was calculated ([Figure 3] and [Figure 4] for dentulous patient and [Figure 5] and [Figure 6] for edentulous patient). | Figure 1: Dentulous patient, horizontal arm of goniometer axis passing through pupillary line and parallel to base of mandible
Click here to view | ,  | Figure 2: Edentulous patient, horizontal arm of goniometer axis passing through pupillary line and parallel to base of mandible
Click here to view | ,  | Figure 3: Vertical dimension at rest measured using digital vernier caliper
Click here to view | ,  | Figure 4: Vertical dimension at occlusion measured using digital vernier caliper
Click here to view | ,  | Figure 5: Vertical dimension at rest measured using digital vernier caliper
Click here to view | ,  | Figure 6: Vertical dimension at occlusion measured using digital vernier caliper
Click here to view |
Without head-stabilizing device
Each subject was asked to sit in the same position ([Figure 7] and [Figure 8] for dentulous and edentulous respectively). Next, the measurements were obtained without head-stabilizing device. The freeway space was measured using digital calipers. Tapes were applied on the points of nose and chin, and circles of approximately 0.3 mm in diameter were marked on these tapes. The tips of the calipers were placed in the center of these marks during measurements of the distance between nose and chin. First, the measurement of vertical dimension at rest ([Figure 9] and [Figure 10] for dentulous and edentulous respectively) and vertical dimension at occlusion was ([Figure 11] and [Figure 12] for dentulous and edentulous respectively) recorded by vernier caliper and then after that freeway space was calculated., ,  | Figure 9: Vertical dimension at rest measured using digital vernier caliper
Click here to view | ,  | Figure 10: Vertical dimension at rest measured using digital vernier caliper
Click here to view | ,  | Figure 11: Vertical dimension at occlusion measured using digital vernier caliper
Click here to view | ,  | Figure 12: Vertical dimension at occlusion measured using digital vernier caliper
Click here to view |
Statistical analysis
Independent t test was carried out for obtaining statistical difference.
Results | |  |
Freeway space without head-stabilizing device for dentulous and edentulous subjects was 4.8 mm and with stabilizing device was 2.2 mm, which was near to precise value, and was found to be significant with head-stabilizing device.
Discussion | |  |
Changes in occlusal vertical dimension (OVD) certainly affect aesthetics and functional activities such as chewing and speech due to their intrinsic relationship with the freeway space and the speaking space. Johnson et al.[6] found a wide range for the freeway space (2–7 mm), which could lead to inaccurate determination of the OVD when standardized values are used (2–4 mm). The interactions between head musculature and dental occlusion have been well documented as early as 1950 when Brodie[7] found that the rest position of the mandible is determined by muscular equilibrium between muscles of mastication and posterior cervical muscle. Goldstein et al.,[8] by using kinesiograph, determined that the forward head position was accompanied by a change in the mandibular postural position that manifested itself as a significant decrease of the physiological freeway space as a result of upward and backward displacement of the mandible. Yamada et al.[9] investigated the effects of head posture on mandibular habitual closing movements. As the head is bent forward, the closing path approached the maximum intercuspal position from the anterior region, and as the head is bent backward, the closing path approached the maximum intercuspal position from the posterior region. A correlation between head posture and stability of the closing movement was reported. It was reported that the forward bending of the head decreased the stability of the closing path, and conversely, the backward bending increased the stability of the closing path. Clinicians have confirmed that the head posture affects the direction and stability of the mandibular closing movements due to masticatory muscle activity, tension, and resistance of inframandibular soft tissue, varying with the changes in head posture.
Conclusion | |  |
These results clarified that the head-stabilizing device obtained excellent reproducibility compared to the conventional methods.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | Yuko W, Fumi M, Toshihide S, Kaoru K. Highly producible method for determination of occlusal vertical dimension: Relationship between measurement of lip contact position with the closed mouth and area of upper prolabium. J Prosthodontic Res 2018; 06:005. |
2. | Clayton AC. A review of the clinical significance of the occlusal plane: Its variation and effect on head posture. Int Coll Craniomandibular Orthop (ICCMO) Anthol 2007;VII:003. |
3. | Pleasure MA. Correct vertical dimension and freeway space. J Am Dent Assoc 1951;43:160-3. |
4. | Toolson LB, Smith DE. Clinical measurement and evaluation of vertical dimension. J Prosthetic Dent 2006;03: 013. |
5. | Zarb GA, Hobkirk J, Eckert S, Jacob R. Prosthodontic treatment for edentulous patients. complete dentures and implant-supported prostheses. St. Louis, Missouri: Mosby Elsevier; 2013. p. 274-83. |
6. | Johnson A, Wildgoose DG, Wood DJ. The determination of freeway space using two different methods. J Oral Rehabil 2002;29:1010-3. |
7. | Brodie AG. Anatomy and physiology of head and neck musculature. Am J Orthod 1950;36:831-40. |
8. | Goldstein DF, Kraus SL, Williams WB, Glasheen-Wray M. Influence of cervical posture on mandibular movement. J Prosthet Dent 1984;52:421-6. |
9. | Yamada R, Ogawa T, Koyano K. The effect of head posture on direction and stability of mandibular closing movement. J Oral Rehabil 1999;26:511-20. |
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12]
|