Lip Pressure Research Articles

Apparatus for measuring lip pressure on reed of woodwind instruments

An apparatus which measures the deflection of a single or double reed of a woodwind musical instrument. A strain measuring transducer affixed to the reed measures the amount of pressure applied by the players lip or lips to said reed. In the preferred embodiment, the signal indicative of the deflection is delivered to the bridge completion circuit. This circuit is amplified by the high gain amplifier to a level that can be read by the adjustable peak level indicator or viewed on a readout meter. A method whereby musicians are provided with an indication of lip pressure for comparison and analysis. The signal can also be viewed on a time based voltage recorder or spectrum analyzer for quantitative lip pressure effects as well as timbre characteristics of different mouthpieces, reeds, ligatures and instruments.

Cheek and lip pressure against maxillary dental arch during dummy sucking

The sucking pattern and intra-oral negative air pressure were studied simultaneously with the cheek/lip pressure in 12 children when sucking a dummy. The cheek/lip pressure was measured at the canine and at the second primary molar on the right side of the upper dental arch. The cheek/lip pressure peaks followed the intra-oral negative air sucking pressure peaks continuously. In the canine region the mean value of maximum cheek/lip pressure was 54 g/cm2. The corresponding value at the second primary molar was 21 g/cm2. During dummy sucking the mean cheek/lip pressure was 3.4 times higher against the canine compared to the second molar (P less than 0.001). The intra-oral negative air pressure was approximately the same whether the cheek/lip pressure was measured at the canine or at the second primary molar. The results indicated that the circumoral muscles were especially active during dummy sucking, in addition to the cheek pressure in the canine region.

The perioral muscular phenomenon: Part II.

Abstract Over twenty-five years of studying the perioral musculature, clinical observation of the dental and peridental tissues of hundreds of patients, and examining seven anatomy books — have revealed that there is a serious deficiency in our knowledge of this musculature and its effects on the dental tissues and this part of the face. Believed to be of no unusual significance, it has been almost ignored through the years. One hears vague terms such as lip pressure and cheek pressure; but no comprehensive studies of this musculature, how it functions and the effects of these functions are to be found in literature. By its actions, this musculature effects many phases of dentistry, directly or indirectly; and orthodontics is affected most of all. By its manipulations of the dental tissues, the alveolar bone and gingiva, it ultimately determines the position of the teeth. Almost every person exhibits pressure signs or damage to the tissues. The only exceptions are babies. By reading these signs, the strength and physical configuration of the pertinent parts of the musculature can be determined. This ability to ‘read the signs’ should be developed since it helps fine tune the diagnostic process. Only by this means may the correct surgical procedures be carried out. A representative sample from over 1200 cases treated in this manner in more than twenty years will be shown.

Pharmacologic Manipulation of Postoperative Labial Wound Contraction and Midfacial Growth in Rabbits

Recent experimental work has suggested that increased lip pressure and scar contraction following lip repair with wide soft-tissue undermining may, in part, contribute to midfacial growth inhibition. The present study was designed to test this hypothesis through the application of pharmacologic agents reported to minimize scar contraction. Thirty-six 6-week-old rabbits were divided into six groups: unoperated controls, rabbits with surgically created defects left unrepaired (surgical controls), and four groups of rabbits with surgically created defects with lip repair and wide undermining on the maxillary surface. Animals with lip repair received either no injections or labial subcutaneous injections of distilled water (route-of-injection controls), normal saline, or papaverine hydrochloride for 2 weeks postoperatively. Rabbits with lip repair and saline or papaverine injections showed significantly (p less than 0.05) decreased lip pressure, relatively hypotonic orbicularis oris muscle EMG activity on the cleft lip side, and greater anteroposterior facial growth (assessed radiologically) from 2 to 24 weeks postoperatively compared with rabbits with lip repair and postoperatively compared with rabbits with lip repair and no injections or distilled water injections. Preliminary results suggest that wound contraction following lip repair and soft-tissue undermining may contribute to mid-facial growth inhibition, which may be reduced by pharmacologic manipulations in the rabbit model.

SIMULTANEOUS MEASUREMENT OF MASS FLUX AND STEAM QUALITY IN GEOTHERMAL WELLS USING HOMOGENEOUS AND SEPARATED FLOW MODELS

Abstract This paper discusses the simultaneous prediction of mass flux and steam quality from two measurements, critical flow lip pressure and pressure drop across an orifice. The James equation for predicting mass flux during two-phase critical flow of steam and water in geothermal wells from lip pressure and stagnation enthalpy data is used. For two-phase flow across an orifice, the separated flow model proposed by Chisholm is used, with modification to account for the upstream fluid momentum. These predictions are compared with the data gathered by James and with the predictions of the James orifice correlation. The study indicates that for low qualities (quality < 40%), the modified separated flow model is as good as the James correlation in predicting the James data. However, the prediction accuracy of both the approaches are unacceptably low at higher steam quality. A sensitivity analysis is done which indicates that the inaccuracy in prediction arises from the coupled nature of the critical flow eq...

A technique for measurement of intraoral lip pressures with lip bumper therapy

One of the reported effects of functional appliance therapy is muscular adaptation achieved through the use of vestibular shields. To develop a method for measuring these effects, 10 children with Class I molar occlusion in the late mixed-dentition stage underwent lip bumper therapy for 8 months. Semiconductor pressure transducers mounted on Tru-Tain stents in the mandibular midline and left canine areas were used to measure lip pressures with the patient at rest and during five functional exercises. Resting and speaking lip pressures for the midline transducer showed significant increases 1 month after lip bumper placement and then decreased to near or below pretreatment levels, possibly an adaptive response. Left-side resting pressures also showed a gradual decrease. In contrast, left-side speaking pressures showed no significant changes over time. The swallowing pressures were not replicable because of excessive background fluctuations. The results of this study indicate that this method has potential for improving clinical diagnosis. The preliminary data also suggest an adaptive response of lip muscles that varies according to anatomic location.

The perioral muscular phenomenon: Part I.

Abstract More than twenty-five years of studying the perioral musculature, clinical observation of the dental and peridental tissues of hundreds of patients, and examining seven anatomy books — have revealed that there is a serious deficiency in our knowledge of this musculature and its effects on the dental tissues and this part of the face. Believed to be of no unusual significance, it has been almost ignored through the years. One hears vague terms such as lip pressure and cheek pressure; but no comprehensive studies of this musculature, how it functions and the effects of these functions are to be found in literature. By its actions, this musculature effects many phases of dentistry, directly or indirectly; and orthodontics is affected most of all. By its manipulations of the dental tissues, the alveolar bone and gingiva, it ultimately determines the position of the teeth. Almost every person is a live laboratory specimen in which pressure signs or damage to the tissues can be observed. By reading these signs, the strength and physical configuration of the pertinent parts of the musculature can be determined. This ability to ‘read the signs’ should be actively developed to fine tune the diagnosis. The perioral musculature phenomenon is a significant aetiological factor in many malocclusions.

Measurement of Upper Lip Pressures in the Course of Myofunctional Therapy

Measurement of Upper Lip Pressures in the Course of Myofunctional Therapy

A study of the relationship of maximal perioral muscle pressure to tonic resting pressure using a pneumohydraulic capillary infusion system

The tonic (resting) and peak (maximum) lip pressures of 100 subjects were measured. The purpose was to evaluate the validity of the assumption that high peak pressures are indicative of high tonic pressures and vice versa. This paper describes the equipment and techniques devised to test these pressures. The results showed no statistically significant relationship whatsoever between tonic and peak lip pressures. We, therefore, suggest that maximum lip pressures not be used as a diagnostic aid in orthodontics. [Reprinted from The Angle Orthodontist, Fall 1990, vol. 60, pages 215-220]

MODIFICATIONS OF JAMES CORRELATION FOR PREDICTING MASS FLUX AND STEAM QUALITY IN GEOTHERMAL WELLS CONTAINING DISSOLVED GASES AND SOLIDS

In geothermal wells, the usual industry practice for rate measurement during simultaneous flow of steam and water is to obtain critical flow of the two-phase mixture by making it flow through a small tube. The mass flow rate is estimated using the James correlation which relates the critical two-phase flow rate with lip pressure and stagnation enthalpy data. The correlation, however, does not account for dissolved solids or gases in the produced fluids. This paper presents extensions of the James correlation for critical flow to account for the presence of dissolved gases (e.g. CO2) and solids (e.g. salts). The effect of dissolved gases is accounted for by subtracting the vapor pressure of the gas from the lip pressure. For brine solutions, it is proposed that brine enthalpy be used for calculating stagnation enthalpy at tip pressure in the James correlation. The modifications proposed show that the estimates for both mass flux and quality are significantly affected by the presence of brine and dissolved ...

A study of the relationship of maximal perioral muscle pressure and tonic resting pressure using a pneumohydraulic capillary infusion system.

The tonic (resting) and peak (maximum) lip pressures of 100 subjects were measured. The purpose was to evaluate the validity of the assumption that high peak pressures are indicative of high tonic pressures and vice versa. This paper describes the equipment and techniques devised to test these pressures. The results showed no statistically significant relationship whatsoever between tonic and peak lip pressures. We, therefore, suggest that maximum lip pressures not be used as a diagnostic aid in orthodontics.

Adaptations in tip posture and pressure following orthognathic surgery

Lip pressures before and after orthognathic surgery were studied to evaluate the relationship between posttreatment soft-tissue adaptation and incisor stability. After all surgical procedures, physiologic adaptation resulted in the maintenance of pressures during speech and swallowing. When the maxilla was advanced by LeFort I osteotomy, a significant decrease in resting pressure of the upper lip was observed instead of the expected increase and incisor stability did not seem related to soft-tissue influences. When the mandible was advanced by sagittal split osteotomy, resting pressure did not increase as expected-, but there was a tendency for incisors to become more upright after fixation release, perhaps as a rebound from labial tipping in fixation. When soft tissues were relaxed as the mandible rotated forward following superior repositioning of the maxilia, resting pressures decreased and lower incisors tended to be positioned forward as predicted by equilibrium theory.

紙の表面マイクロトポグラフィー ＩＶ 水の転移におよぼす荷重の影響

The relation between the micro-topography of paper surface and liquid absorption in minute time was investigated on softwood and hardwood bleached sulphate sheets and an india paper by an apparatus, which was originally designed by Bristow and modified in order to be able to change the lip pressure.It was found the Parker Print-Surf roughness increased a little in case of the hardwood bleached sulphate sheet and decreased in the softwood sheet and the india paper, when the lip pressure increased. The value of Rp decreased at the clamping pressure of 10 kg/cm2 and increased at 20 kg/cm2 in all cases. The roughness index calculated from the dynamic liquid absorption decreased in both softwood and hardwood sheets with lip pressure. The distribution of depth of void on paper surface measured from the stylus type smoothness tester became wider on the softwood sheet and the india paper, but narrower in the hardwood sheet.

Der einfluß der lippenplastik auf die dentofaziale entwicklung be! patienten mit Lippen-Kiefer-Gaumen-Spalten: I. Jonas, H. IF. Kappert, E. Raider, T. Rakosi, W. Schilli, and U. Joos Fortschr. Kiefenorthop. 1986:400–411

The effect of primary lip repair on the dentofacial morphology was analyzed in 25 adolescents with cleft lip and palate by means of (a) upper lip pressure measurement, (b) electromyography of the labial musculature, (c) roentgenocephalometric and soft-tissue analyses of the lateral head plate, and (d) plaster model analysis. The results were compared with those of 15 patients presenting with normal occlusal and functional relationships. Only the resting pressure of the upper lip correlated with the vertical and sagittal dentofacial morphology in patients with cleft lip and palate. This relation is attributed to the unbalanced and unfavorable functional-mechanical strain of the perioral muscles in these cases. The strain of the repaired upper lip on the underlying skeletal structures correlated with (a) the resting activity of the upper lip and (b) the strain direction being determined by the length and thickness of the labial sofit tissue. The results were specific for patients with cleft lip and palate, and were not correlated to the patient’s age and sex. Contrary to the dental parameters, the skeletal disturbances as a consequence of the muscular imbalance could not be significantly altered by orthodontic treatment. The choice of technique of primaIy upper lip repair in patients with cleft lip and palate is important both for their dentofacial development and for their possible orthodontic Weatment result. Theoretically, from the functionalmechanical aspect, their results indicate that Delaire’s method of primary functional upper lip repair is the most suitable technique. Alex Jacobson Reviews and abstracts 447

Organic tissue glue in the closure of cataract incisions

We report our initial studies with a new organic tissue glue (Tisseel) in the closure of cataract incisions made in fresh cadaver eyes. We made two types of cataract incisions, posterior beveled and scleral pocket, and closed them with nylon sutures, glue, or a combination of both. The 11-mm posterior-beveled incision required eight nylon sutures, with or without glue, to maintain wound integrity at high intraocular pressures. We found the 7-mm and 11-mm pocket-type incisions to be essentially self-sealing and to leak only when posterior scleral lip pressure was applied. Once glue was added, even high posterior pressure did not disrupt the wound. This glue may thus present an alternative to suture closure of scleral pocket cataract incisions.

Changes in lip pressure following extension and flexion of the head and at changed mode of breathing

The changes in upper and lower resting lip pressures following extension and flexion of the head and at changed mode of breathing were studied in a sample of 15 adults with Class I molar relationship. The lip pressure was measured with bonded strain gauge transducers on the upper and lower central incisors. The transducers could be calibrated directly in the subject's mouth. The upper and lower lip pressures during natural head posture had a mean value of 3.91 g/cm 2 and 8.58 g/cm, 2 respectively. The mean values of the differences between pressures obtained during natural head posture and during 5°, 10°, and 20° of extension showed a continuously, highly significant increase in pressure. During 5°, 10°, and 20° of flexion, the upper lip pressure continuously decreased with highly significant values. Changes in the lower lip pressure during flexion were difficult to measure because of intense muscle activity. A significant decrease was shown for the difference in upper and lower lip pressures between nose breathing and mouth breathing, whereas there was a significant increase in pressure when the subject extended the head 5° during mouth breathing.

有歯顎および無歯顎の舌房形態の比較

For formation of artificial dental arch, roughly two methods are available : anatomical indices as reference and use of physiological functions. Therefore, positional relation among the anatomical alveolar ridge crest of the mandible, the prosthetic alveolar ridge crest which is the median point of the buccolingual alveolar ridge, and the median point of the neutral zone was investigated with use of 33 edentulous subjects. Natural teeth are said to erupt at positions where tongue, cheek, and lip pressures are equal and to form the dentition. This theory appears to be comparable with the theory of the neutral zone for edentulous subjects. Morphology and area of the tongue space, therefore, were compared in 78 normal dentulous subjects and 33 edentulous subjects. The results were as follows : 1. Length, width, and area of the tongue space in edentulous subjects were 40.4±3.5mm, 52.1±3.7mm, and 1354±209mm^2, respectively, for male ; 39.6±3.4mm, 52.1±2.9mm, and 1265±210mm^2, respectively, for female. No significant difference between male and female was found for all the items measured. Values of measurement tended to decrease with aging. This tendency was found to be closely related with reduction in physiological functions. 2. The anatomical alveolar ridge crest and the prosthetic alveolar ridge crest were located about 2mm more lingually than the neutral zone taken by use of physiological functions. 3. Length, width, and area of the tongue space in normal dentulous subjects were 43.8±2.2mm, 45.0±2.6mm, and 1437±114mm^2, respectively, for male ; 43.1±2.7mm, 42.5±1.6mm, and 1334±116mm^2, respectively, for female. 4. On the basis of the foregoing findings, the tongue space at the neutral zone in edentulous subjects, as compared with the tongue space of normal dentulous subjects, was shorter in length and considerably wider.

Lip Pressure on Prosthetic Appliances in Cleft Lip and Palate Patients

Lip Pressure on Prosthetic Appliances in Cleft Lip and Palate Patients

Pressure from the lips on the teeth and malocclusion

The relationship between lip strength and lip pressure (pressure from the lips on the teeth) was studied in 84 children (aged 7 to 16 years) with varying types of malocclusion. The lip strength was recorded with a dynamometer. The lip pressure was measured on the upper and lower central incisors in the rest position, and during chewing and swallowing of crispbread. The lip pressure measurements were made with an extraoral pressure transducer incorporated in a water-filled system with an extaoral mouthpiece. The muscle activity of the lips was recorded electromyographically. Bite and facial morphologies were studied on dental casts and profile cephalograms. There was no correlation between lip strength and lip pressure. Lip strength was lower in children with Angle Class II, Division 1 malocclusion than in children with Class I malocclusion. The lip pressure on the upper incisors, on the other hand, was higher in Class II, Division 1 than in Class I malocclusion, and was lowest in children with Class II, Division 2 malocclusion. The findings suggest that the pressure from the lips on the teeth is a result of the incisor position.

Measurements of lip pressure exerted on a cigarette during normal smoking

Measurements were made of the pressure exerted by human lips on the filter of a cigarette during normal smoking conditions using a small, fluid-filled bulb attached to a low-compliance pressure transducer. In two series of measurements, the mean lip pressure and standard error were 34.2 (±2.6) and 35.8 (±3.1) torr respectively. These pressures compared favorably with those applied by the Cambridge holder (used in the standard FTC testing procedure), but were much lower than the pressures exerted by the Filtrona and Borgwaldt holders, both of which are constructed from a rigid cylindrical housing with a segment of latex tube mounted inside. Pressures measured by these two holders were in close agreement with the pressures predicted by a nonlinear theoretical model for the distention of latex rubber tubes.