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PubMed1986

Cleft palate repair by double opposing Z-plasty.

In an attempt to improve speech results following palate repair while allowing adequate maxillary growth, a palatoplasty using two opposing Z-plasties of the soft palate, one of the oral and one of the nasal layers, has been used in 22 infants. Eight patients had unilateral cleft lip and palate, eight had bilateral cleft lip and palate, and six had cleft palate. The Z-plasties facilitate effective dissection and redirection of the palatal muscles to produce an overlapping muscle sling and lengthen the velum without using tissue from the hard palate, which permits hard palate closure without pushback or lateral relaxing incisions. Of the 20 children old enough for speech evaluation, 18 have no velopharyngeal insufficiency. Two have very mild velopharyngeal insufficiency. None has required a pharyngeal flap.

Cleft Palate↗
PubMed1995

Histomorphologic analysis of the soft palate musculature in prenatal cleft and noncleft A/Jax mice.

The two specific aims of this study were as follows: to evaluate the appropriateness of the A/Jax mouse model in the investigation of the key cellular stages in prenatal soft palate morphogenesis and myogenesis; and to describe structural differences in the histomorphology of the soft palate anatomy from cleft and noncleft mice prior to, during, and after palatogenesis. Cleft-induced and control groups of A/Jax mouse embryos from timed pregnancies were harvested sequentially on gestational days 15 to 19. Embryos were weighed and staged for external body morphology. The heads were removed and fixed for light microscopy, sectioned serially in the frontal plane at 10 microns and stained with hematoxylin-eosin to characterize and compare the soft palate musculature. All observations were made at the head depth of the trigeminal ganglion in both age- and stage-matched embryos. The following findings were made: (1) the A/Jax mouse is a suitable animal model for the study of soft palate myogenesis; (2) there were no discernible morphologic differences between the soft palate muscles in cleft and noncleft A/Jax mice when viewed under light microscopy; (3) the soft palate and related muscles were identifiable as muscle fields, in both the cleft and noncleft fetuses, as early as gestational day 15 and as specific muscles at gestational day 18; (4) in both the cleft and noncleft A/Jax fetuses, the soft palate muscles appeared in a sequential anatomic fashion (the palatine aponeurosis appeared first, next the tensor palatini, and then the levator palatini muscles); and (5) in the cleft palate fetuses, both pterygoid plates were angulated and displaced laterally.

Analysis of Variance↗
PubMed2003

Bilateral superiorly based full-thickness nasolabial island flaps for closure of residual anterior palatal fistulas in an unoperated elderly patient.

OBJECTIVE: Unoperated bilateral complete cleft lip and palate in an adult or elderly patient is seen rarely, and the existence of unoperated clefts is a result of unfavorable economic and social circumstances. We report an unoperated 65-year-old patient with bilateral complete cleft lip and palate and present our preference for the surgical management. INTERVENTIONS: Repair of the bilateral complete cleft lip and palate was successfully carried out using straight-line closure for the bilateral cleft lip and two-flap pushback palatoplasty with superiorly based lateral port control pharyngeal flap for the wide cleft palate at the first stage, and large residual anterior palatal fistulas were closed using bilateral superiorly based (retrograde flow) full-thickness nasolabial island flaps at the second stage. CONCLUSIONS: To our knowledge based on a review of the literature, this is the first report of an elderly patient with bilateral complete cleft lip and palate and the first application of bilateral superiorly based (retrograde flow) full-thickness nasolabial island flaps for closure of large residual anterior palatal fistulas or alveolar clefts. The bilateral superiorly based (retrograde flow) full-thickness nasolabial island flap may be a good solution in large anterior palatal defects using unilaterally or bilaterally in a single stage with minimal donor site morbidity, in which there is not enough tissue for local repair or if previous attempts are unsuccessful.

Aged↗
PubMed1979

Experimental induction of premature movement of rat palatal shelves in vivo.

In order to enhance further knowledge of palatal shelf movement and the factors involved in palate closure, a method was developed for prematurely elevating palatal shelves in utero. Approximately 7 hours before expected shelf elevation, pregnant Sprague-Dawley rats were laparotomized and two medially directed squeezes were applied to the face of some of the embryos through the intact uterine wall. Palates from control (unsqueezed) and experimental animals were obtained immediately after the procedure and 2, 4, 7, 12 and 24 hours later. In the 0, 2 and 4 hours groups, 82% of experimental palates were elevated, whereas only 6% of control palates were elevated. At 0 hours only the hard palate in the experimental group had elevated, but at 2 and 4 hours almost half this group showed elevation of the soft palate as well, and, in addition, contact had been made between the elevated shelves.

Animals↗
PubMed2005

Effects of epidermal growth factor (EGF), transforming growth factor-alpha (TGFalpha), and 2,3,7,8-tetrachlorodibenzo-p-dioxin on fusion of embryonic palates in serum-free organ culture using wild-type, EGF knockout, and TGFalpha knockout mouse strains.

BACKGROUND: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is teratogenic in mice, producing cleft palate (CP). TCDD exposure disrupts expression of epidermal growth factor (EGF) receptor, EGF, and transforming growth factor-alpha (TGFalpha) in the palate and affects proliferation and differentiation of medial epithelial cells. EGF knockout embryos are less susceptible to the induction of CP by TCDD. This study used palate organ culture to examine the hypothesis that EGF enables a response to TCDD. METHODS: The midfacial tissues from wild-type (WT), EGF knockout, C57BL/6J, and TGFalpha knockout embryos were placed in organ culture on gestational day (GD) 12. Palatal explants were cultured for 4 days in serum-free Bigger's (BGJ) medium with 0.1% dimethyl sulfoxide (DMSO) or 1 x 10(-8) M TCDD with or without 2 ng of EGF/ml, 1 or 2 ng of TGFalpha/ml. Effects on palatal fusion were evaluated on day 4 of culture. EGF levels in explants and medium were determined using Luminex technology. RESULTS: In serum-free, control medium, palates from all of the strains fused. EGF knockout palates cultured with TCDD (no EGF) fused, but those cultured with TCDD + 2 ng of EGF/ml failed to fuse (p < 0.05 vs. control or TCDD without EGF). TGFalpha knockout palates failed to fuse when cultured with TCDD + 2 ng of TGFalpha/ml. EGF levels increased in tissue and accumulated in the medium after 24 hr of culture. CONCLUSIONS: This study demonstrated that providing EGF to the palates of EGF knockout mice restored the response to TCDD. These studies support the hypothesis that the mechanism for induction of CP by TCDD is mediated via the EGFR pathway.

Animals↗
PubMed1999

Individual differences in the use of pleasantness and palatability ratings.

Previously we have suggested that individual subjects interpret the phrase "palatable food" in different ways. To test the consistency of the use of this term, 50 male volunteers consumed a simple lunch on two occasions, once with a more palatable food and once with a more bland version. Ratings of hunger, fullness, pleasantness and palatability were completed at the start and end of each meal. Overall, subjects ate slightly more of the palatable food. The difference in intake between conditions correlated with differences in pleasantness and palatability but not hunger at the start of eating. Rated pleasantness of the food declined between the start and end of the meal in most subjects, but changes in palatability were more variable, with a significant minority showing no change across the meal. Detailed analysis confirmed the existence of two populations of responses, one where pleasantness and palatability were synonymous, and one where palatability was rated as a constant property of a food. The existence of two interpretations of the term palatability in common English usage cautions against the use of this term as a reliable means of evaluating hedonic responses to foods in appetite studies.

Adolescent↗
PubMed1990

Some suggestions on dealing with palatability--response to Ramirez.

The understanding of the word "palatability" is explained within a research context consisting of four components: an ingestor, an ingestant, a response measure, and an observer. Within this context a solution is proposed to the circularity of an observer measuring palatability by the amount of ingestive activity and in turn attributing the amount ingested to a measure of palatability. The use of measurements under standardized conditions is emphasized and the suggestion is made that palatability be qualified by the operations which affect variability in measurements of its magnitude. For example, "intrinsic" or "food-generated palatability" is defined as the variability in ratings attributable to changes in the sensory properties of ingested items which are intrinsic to the items being tested. "Learned palatability" could be used for changes in the response to a food attributable to pairing of its sensory properties with post-ingestional effects. The way out of the dilemma posed by the question "do palatable foods induce obesity?", is to determine the relative contributions to excessive intake, which can induce obesity, made by the various sorts of palatabilities, designated by the operations which generate their definitions. In the end this process could render the word "palatable" obsolete.

Appetite↗
PubMed2004

Obstructive sleep apnea and ageing Myotonometry demonstrates changes in the soft palate and tongue while awake.

Upper airway dilator muscles are important in the pathogenesis of obstructive sleep apnea syndrome (OSAS). The present study compares changes of tissue properties between the soft palate and tongue in different age groups of apnea patients and healthy subjects. Materials and methods: OSAS patients diagnosed by polysomnography (15 patients - aged 30-70 years; 10 patients - aged 18-29 years) and healthy volunteers (10 subjects - aged 30-70 years; 10 patients - aged 18-29 years) participated in the study. Computerized endopharyngeal myotonometry was used to measure the biomechanical properties - stiffness and elasticity of the soft palate [M. Veldi, V. Vasar, A. Vain, T. Hion, M. Kull, Computerized endopharyngeal myotonometry (CEM): a new method to evaluate the tissue tone of the soft palate in patients with obstructive sleep apnea syndrome, J. Sleep Res. 9 (2000) 279-284; M. Veldi, V. Vasar, T. Hion, M. Kull, A. Vain, Ageing, soft-palate tone and sleep-related breathing disorders, Clin. Physiol. 21 (2001) 358-364] and lingual tissues [M. Veldi, V. Vasar, T. Hion, A. Vain, M. Kull, Myotonometry demonstrates changes of lingual musculature in obstructive sleep apnea, Eur. Arch. Otorhinolaryngol. 259 (2002) 108-112; M. Veldi, V. Vasar, T. Hion, A. Vain, M. Kull, Myotonometry demonstrates changes of soft palate and genioglossal muscle in obstructive sleep apnea, Sleep Med. 4 (Suppl. 1) (2003) S49] during wakefulness. Results: We did not find any statistical differences in tissue properties between the soft palate and the tongue tissues, either stiffness or elasticity, in young non-snorers and young patients of apnea (P > 0.05). The stiffness of the soft palate of middle-aged apnea patients was increased compared with the tongue (P < 0.001). The elasticity of tongue of middle-aged patients of apnea was decreased compared with the soft palate (P < 0.001). Conclusions: The biomechanical properties of the soft palate and the tongue undergo different changes in the case of snoring and upper airway obstruction and ageing.

Journal Article↗
PubMedDate not supplied

Palatability and intake relationships in free-living humans. characterization and independence of influence in North Americans.

In order to investigate palatability influences on the ad lib eating behavior of free-living humans, 564 participants were paid to maintain food intake diaries for 7 days. They recorded their intake along with a global rating of the palatability of the entire meal on a seven-point scale. It was found that most meals that are self-selected are palatable and that only 9.3% are rated as unpalatable. Meals that were highest in palatability were 44% larger than meals that were low in palatability, but palatability only accounted for around 4% of the variance in meal sizes. Multiple regression demonstrated that palatability appears to act on intake independent of the levels of other influential factors. These results were very similar to those observed for the French and suggest that palatability operates similarly on intake regardless of culture. Palatability appears to be an influence on the amounts ingested by free-living humans in their natural environments but appears to be only one of many influential factors and accounts for only a small proportion of the variance in intake.

Adolescent↗
PubMed2001

Three-dimensional hard tissue palatal size and shape in human adolescents and adults.

Hard tissue palatal dimensions and shape in 29 boys and 32 girls (mean age 14 years) and 30 men and 35 women (mean age 20 years), all with a complete permanent dentition including the second molars, and free from respiratory problems, were analyzed. Palatal landmarks were digitized with a computerized 3D instrument, and their coordinates were used to derive a mathematical model of palatal form. Palatal shape (size-independent) was assessed by a four-order polynomial in the sagittal and frontal plane projections. Palatal dimensions in the frontal and sagittal planes were computed, and compared between ages and sexes by two-way factorial analyses of variance. The effect of age on palatal shape was different in the two sexes: while in females the curves in both the frontal and sagittal planes were practically superimposed, in males the youngest subjects had somewhat 'lower' curves than the oldest subjects. Sex had a significant (p<0.05) effect for all variables. Age was significant only for palatal slope in the sagittal plane (p<0.01), and for raphe inclination in the horizontal plane (p<0.05). For all variables but palatal length in the sagittal plane, a significant (p<0.01) sexxage interaction was found: while in males all linear variables were larger in adults than in adolescents, the reverse was found in females. Overall, while in adolescent females palatal form appeared to have already attained adult characteristics, in males some modifications between adolescence and young adulthood were measured. These modifications should be taken into consideration as a possible factor of relapse after orthodontic treatment.

Journal Article↗
PubMed1997

Effect of food palatability on early (cephalic) phase of diet-induced thermogenesis in nonobese and obese man.

OBJECTIVE: To study the effect on the early (cephalic) phase of diet-induced thermogenesis (EDT) of palatable vs unpalatable food, in nonobese and obese man. SUBJECTS: Twenty-four nonobese volunteers and 19 obese clinic patients. DESIGN AND MEASUREMENTS: A palatable, liquid formula meal of Ensure (1048 KJ, 450 ml), and of Ensure made unpalatable by addition of aqueous KCl, were sipped on nonconsecutive mornings. O2 consumption (ml/min) was measured before, and starting 30, 60 and 90 min after beginning the test meal, from which EDT was calculated as KJ/min. RESULTS: Palatability of the test meal significantly increased EDT (palatability effect, P = 0.004) but obesity status per se, did not affect EDT. Nevertheless, the effect of palatability on EDT was dependent on obesity status, being seen only in the nonobese. EDT was significantly greater in the nonobese after the palatable than the unpalatable meal: (mean +/- s.e.m.) 2.45 +/- 0.14 vs 1.83 +/- 0.14; P < 0.0001, but not in the obese: 1.93 +/- 0.28 vs 1.73 +/- 0.20; P < 0.21. Therefore only after the palatable meal was EDT less in the obese compared with the nonobese: P < 0.05. The threshold for the unpleasant taste of added KCI was 31% higher in the obese than the nonobese: 4.2 +/- 0.4 vs 3.2 +/- 0.2 [g KCI]; P < 0.025. CONCLUSIONS: The early (cephalic) phase of dietary thermogenesis (EDT) is significantly increased in the nonobese by palatability, but not in the obese, so that only after a palatable meal is EDT less, or 'deficient,' in the obese compared with the nonobese. Also, the obese have a higher threshold for the unpleasant taste of KCI (in Ensure) than the nonobese.

Adolescent↗
PubMed2001

Effects of test-meal palatability on compensatory eating following disguised fat and carbohydrate preloads.

OBJECTIVE: To test whether the palatability of a test meal altered compensatory eating following disguised high-energy fat and carbohydrate preloads. DESIGN: Effects of preload energy (low, 265 kJ, or high, 1510 kJ) and test-meal palatability (bland or palatable) were contrasted within-subjects, with a between-subjects contrast of fat and carbohydrate preloads. SUBJECTS: Twenty-four healthy, normal men (age 23.6+/-1.0 y, (body mass index) BMI 21.3+/-0.5). MEASUREMENTS: Microstructural analysis of test meal intake and rated appetite in the four test conditions, plus diary-based weighed intake analysis of energy intake post-lunch. RESULTS: Subjects ate significantly less at lunch after disguised high-energy fat or carbohydrate preloads relative to the low-energy preload, and ate significantly more of the palatable than bland lunch in all conditions. The reduction in eating following the high-energy preload was significantly less in the palatable condition. Intake post-lunch did not differ between conditions, and overall subjects had higher daily energy intake on the days they consumed the high-energy preloads. Rated hunger was significantly less 30 min after the high- than low-energy preloads, but increased on tasting the palatable food in all conditions. The high-energy preloads suppressed appetite immediately post-lunch. No differences between fat and carbohydrate were found on any measure. CONCLUSIONS: Manipulation of the palatability of a test meal modified the ability to respond to disguised high-energy preloads, with over-consumption most evident when disguised high-energy preloads were followed by a palatable food. Subsequent voluntary intake compensated for over-consumption of the palatable lunch, but not the high-energy preload.

Adult↗
PubMed2000

[Nonsyndromic cleft lip with or without cleft palate in Chinese population: analysis of 3766 cases].

A retrospective study was conducted to evaluate the variation trend in the incidence and epidemiological characteristics of nonsyndromic cleft lip with or without cleft palate in Chinese population. From 1988 to 1992, data were collected from more than 500 hospital-based units involved in a monitoring program and were analyzed by the National Center for Birth Defects Monitoring. The monitored subjects were the hospitalized births from 28 weeks gestation to a period within 7 days after delivery, which included 3246 408 perinatals and 3766 cases. The total incidence of nonsyndromic cleft lip with or without cleft palate was 11.6/10,000; the total incidence of celft lip alone was 3.8/10,000 and that of cleft lip with cleft palate was 7.8/10,000; no significant variation was noted in the annual incidence from 1988 to 1992. The incidence in males was 13.3/10,000, and 9.5/10,000 in females; there was a significant difference (P < 0.01). Of all the 3766 cases, cleft lip with cleft palate accounted for 67%, unilateral cleft lip 28% and unilateral cleft lip with cleft palate 43%. Left cleft lip and left cleft lip with cleft palate constituted 21% and 29% respectively. The sex-ratio was 1.6:1 for nonsyndromic cleft lip with or without cleft palate. It could be concluded that the incidence of nonsyndromic cleft lip with or without cleft palate showed no variation trend in China. Although no difference was found between urban and rural areas, the susceptibility to the defect was higher in males than in females. Cleft lip with cleft palate was more common than other types. There was a predominance of unilateral defects, of which most were on the left side.

China↗
PubMed1997

Functional outcome in soft palate reconstruction using a radial forearm free flap in conjunction with a superiorly based pharyngeal flap.

BACKGROUND: Speech and swallowing problems due to velopharyngeal incompetence may follow soft palate resection and reconstruction. Over the past 3 years, we have developed the use of a superiorly based pharyngeal flap in conjunction with a radial forearm flap for soft palate reconstruction. METHODS: This paper describes the technique in detail and compares the functional results in a study with patients undergoing soft palate resection for squamous cell carcinoma treated with or without a pharyngeal flap as an adjunct to a radial forearm free flap for soft palate reconstruction. Seven patients had one quarter or one half soft palate defects reconstructed with a radial forearm flap alone. Of the 11 patients undergoing three quarter or total soft palate resections, all were reconstructed with a radial forearm flap, but 5 were treated with an additional superiorly based pharyngeal flap. The functional outcome for all the patients was analyzed and compared. RESULTS: Our results show that the addition of the superiorly based pharyngeal to the radical forearm flap in soft palate reconstruction results in improved speech and swallowing. We recommend the use of the additional flap in resections in which more than one quarter of the soft palate is included.

Adult↗
PubMed2000

Pathogenesis of cleft palate in mouse embryos exposed to 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD).

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces cleft palate in mouse embryos. It has been believed that TCDD inhibits palatal fusion by suppression of disappearance of medial edge epithelial (MEE) cells on palatal shelves. However, we found that exencephalic mouse embryos were resistant to the cleft palate-inducing action of TCDD. In the present study, we examined cell kinetics in MEE and palatal mesenchyme in embryos exposed to TCDD with or without exencephaly for elucidation of pathogenesis of cleft palate by TCDD. Pregnant Jcl:ICR mice were given TCDD orally at 40 microg/kg at gestation day (GD) 12.5. Embryos were harvested between GD 13.5 and GD 14.5 and examined for cell kinetics by bromodeoxyuridine (BrdU) and TUNEL methods. Exencephaly was induced by intraperitoneal injection of CdCl(2) at 6 mg/kg at GD 7.5. BrdU-positive cells were decreased in TCDD-treated embryos in MEE and mesenchymal cells. TUNEL-positive cells were detected in MEE both in TCDD-treated and untreated control embryos, as well as in embryos with or without exencephaly. We also measured the gap between shelves between GD 14. 0 and GD 14.5. There were no differences at GD 14.0 between control and TCDD-exposed embryos, but at GD 14.25 and GD 14.5, TCDD-exposed embryos had wider gaps than controls. These findings indicate that cleft palate by TCDD results from poor development of palatal shelves. Teratogenesis Carcinog. Mutagen. 20:73-86, 2000.

Animals↗
PubMed2005

Elimination of palatal fistula after the maxillary swing procedure.

BACKGROUND: The maxillary swing procedure has been used as an anterolateral approach to expose the nasopharynx, the central skull base, and its vicinity. The reported incidence of postoperative palatal fistula has ranged from 20% to 25%. The oronasal incompetence especially associated with a large fistula has adversely affected normal speech, eating, and swallowing functions. We describe a modified palatal incision to reduce the incidence of palatal fistula associated with the maxillary swing procedure. METHODS: Fifteen consecutive patients who underwent maxillary swing procedures for salvage resection of recurrent nasopharyngeal carcinoma after radiotherapy had the modified palatal incision. The flap was raised as described, and the outcome was analyzed. RESULTS: Fourteen patients' palatal wound healed uneventfully. One patient experienced partial flap necrosis, which healed with conservative treatment. All 15 patients tolerated oral feeding 1 week after the surgery. No palatal fistulas occurred. CONCLUSION: The modified palatal incision as described has effectively prevented palatal fistula formation after the maxillary swing procedure.

Female↗
PubMed2002

Altered mandibular development precedes the time of palate closure in mice homozygous for disproportionate micromelia: an oral clefting model supporting the Pierre-Robin sequence.

BACKGROUND: Development of the human craniofacial anatomy involves a number of interrelated, genetically controlled components. The complexity of the interactions between these components suggests that interference with the spaciotemporal interaction of the expanding tongue and elongating Meckel's cartilage correlates with the appearance of cleft palate. Mice homozygous for the semi-dominant Col2a1 mutation Disproportionate micromelia (Dmm), presenting at birth with both cleft palate and micrognathia, provide the opportunity to test the hypothesis that mandibular growth retardation coincides with formation of the secondary palate as predicted from our understanding of the Pierre Robin sequence. The present study was conducted in embryonic day 14 (E14) mice, 1 day before palate closure, to describe the relationship between growth of the lower jaw/tongue complex versus genotype of the embryo. METHODS: Whole heads, isolated from E14.25, E14.5 and E14.75 wild-type and homozygous mutant embryos, were fixed in Bouin's solution, embedded in paraffin, and serially sectioned. Mid-sagittal sections, stained with toluidine blue, were used to estimate growth of both tongue and lower jaw (Meckel's cartilage length) during a 12-hr period preceding palate closure. RESULTS: In control embryos, the largest increase in Meckel's cartilage length occurred between E14.5 and E14.75. Compared to control, the mean Meckel's cartilage length in the mutant was similar at E14.25, but was significantly less at E14.5 and E14.75. Absolute tongue size in control embryos increased linearly during this period of E14.25 to E14.75. Relative to the rapidly growing Meckel's cartilage, however, relative tongue size in control embryos actually decreased over time. Absolute tongue size in the mutant was not significantly different from that of control at any of the embryonic stages examined, however, relative tongue size in the mutant was significantly greater at E14.75 compared to control. CONCLUSION: Mandibular growth retardation, coupled with relative macroglossia in E14 Dmm/Dmm mice, suggests that the concerted development of the palate and lower jaw complex in the mutant is aberrant. Detection of micrognathia and pseudomacroglossia in homozygotes, before the time of palate closure, supports the hypothesis that a relationship exists between growth retardation of Meckel's cartilage and malformation of the secondary palate, as predicted by the Pierre-Robin sequence.

Animals↗
PubMed1978

The effect of hypervitaminosis A on rat palatal development.

Retinoic acid or retinyl acetate was administered to pregnant rats in doses sufficient to induce a 90% incidence of cleft palate. In another study, a delay in the reorientation of the palatal shelves was observed to be longer with the more potent teratogen, retinoic acid. On day 16 of gestation, 24 hours after final dosage with vitamin A, the synthesis of DNA and protein was studied in fetal carcass, mandible, and palate, and that of sulfated mucopolysaccharides (S-MPS) and glycoproteins (GP) in fetal head, mandible, and palate. Increases in DNA synthesis in fetal palate and in GP synthesis in fetal palate were found; thus, the mechanism of action of vitamin A in inducing cleft palates in rats may be caused by interference with the normal biochemical synthetic pattern of the palatal shelves.

Animals↗