SEARCH · PubMed Health

Results for “BITES”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

PubMed1996

A study of patients with Angle Class I unilateral cleft lip and palate (UCLP) using lateral roentgenographic cephalograms. A comparison between anterior cross-bite UCLP patients and anterior cross-bite non-UCLP, normal bite UCLP or normal bite non-UCLP patients.

In our previous study carried out in 1994, we found 49 patients with unilateral cleft lip and palate (UCLP) among 51 patients with cleft lip and palate who visited the Department of Orthodontics, Nihon University Dental Hospital at Matsudo. In particular, patients with cross-bite (anterior cross-bite) UCLP were predominant, accounting for 21 individuals (41%). In the present study, we reviewed 79 patients with malocclusion including 21 with anterior cross-bite UCLP, who represent the largest subpopulation among patients with cleft lip and palate. These 21 patients were compared with other UCLP patients showing normal bite with regard to morphological differences evident in lateral roentgenographic cephalograms, to establish a proper policy of orthodontic diagnosis and treatment of their condition. The anterior cross-bite UCLP group showed differences in the skeletal pattern and the denture to skeletal pattern from the other patient groups except for the mesio-distal relationship. The anterior cross-bite UCLP group had cross-bite of the concave type, while the normal bite UCLP group had malocclusion of the convex type accompanied by maxillary overdevelopment. Thus, it is suggested that normalization of reversed occlusion leads to favorable growth of the upper jaw in UCLP patients with anterior cross-bite.

Adolescent↗

PubMed1995

A placebo controlled clinical trial investigating the efficacy of a homeopathic after-bite gel in reducing mosquito bite induced erythema.

A randomised, placebo controlled clinical trial was conducted to examine the efficacy of a homeopathic after-bite gel in the symptomatic relief of mosquito bites. Sixty eight healthy volunteers were bitten under laboratory conditions by Aedes aegypti mosquitoes at three spots, on the ventral aspect of the forearm. One bite was treated with the homeopathic after-bite gel, another bite with a placebo gel which was identical in appearance and smell to the homeopathic after-bite gel, and the third bite remained untreated. Immediately after the bites and 1, 3, 6, 26 and 31 hours post-bite, the length and width of the erythema were measured with a calliper, and photographs were taken of the bite sites from which the size of the erythema was subsequently determined. This was followed by assessment of the extent of itching with a verbal analogue scale, and finally treatment took place. For each spot the total erythema was calculated as the area under the plotted curve of the erythema at different time points (mm2*h) and the total sum of the itch scores was determined. For the bites treated with the homeopathic after-bite gel the median total erythema was 10.500 mm2*h. For the spots treated with the placebo gel and the untreated spots the median total erythema was 12.900 mm2*h and 13.300 mm2*h, respectively. The difference between the spots treated with the homeopathic after-bite gel and the untreated spots came close to significance (two-tailed P = 0.06), which was not the case for the difference between the spots treated with the homeopathic after-bite gel and the spots treated with placebo gel (P = 0.13). After pooling the data of a very similar previous pilot study and the present study (ntotal = 83), the homeopathic after-bite gel was significantly superior to no treatment (two-tailed P = 0.003) as well as to placebo gel (two-tailed P = 0.03). Comparing itching after the three treatments, no significant differences could be demonstrated. The extent of itching was positively correlated with the area of the erythema (r = 0.63). Treatment of mosquito bites with the homeopathic after-bite gel will reduce the erythema compared to no treatment. Comparison with the placebo gel suggests it is the plant extracts which are the active components of this gel.

Adult↗

PubMed1992

The effect of treatment of skeletal open bite with two types of bite-blocks.

The treatment of anterior skeletal open bite was studied in two groups of children. The children of one group wore a removable spring-loaded bite-block in the lower jaw for one year. The bite-block exerted an intrusive force on the upper and lower posterior teeth. The children of the other group were treated for 3 months with bite-blocks with repelling magnets. These bite-blocks were cemented on the posterior teeth of both jaws. The effects of treatment were monitored by measurement of the bite-force (group with spring bite-blocks only), by electromyographic recording of the activity of the temporal and masseter muscles, and by X-ray cephalometry. Recordings were made before, during, and at the end of the treatment, and at a follow-up observation. The bite-force increased during the first months of treatment, but was then unchanged. The activity of the masseter muscle during maximal bite also increased in the first part of the period of treatment with a spring bite-block. In the group treated with magnetic bite-blocks, there was an increase in the resting activity of the masseter muscle and in the chewing activity of the anterior temporal muscle. The effects of the treatment on bite and facial morphology were less marked in the group with spring bite-blocks than in the group with magnetic bite-blocks, with an average improvement of the overbite of 1.3 mm with the spring bite-block therapy. In the group with magnetic bite-blocks, the average improvement in overbite was 3 mm. This was thought to be due to anterior rotation of the mandible and increased eruption of the incisors. The mandibular rotation was a result of intrusion of the upper and lower posterior teeth and possibly also increased mandibular growth. A follow-up of the cases treated with magnetic bite-blocks revealed a tendency for the beneficial effects of the treatment to relapse which possibly could be counteracted by a long phase of active retention.

Bite Force↗

PubMed2003

The effects of gape angle and bite point on bite force in bats.

Models of mammalian mastication predict that bite force is affected by both the degree of mouth opening (gape angle) and the point along the tooth row at which force is transferred to a food item (bite point). Despite the widespread use of these models in comparative analyses, experimental data documenting bite force in non-human mammals are extremely limited. The goal of this study is to document variation in non-stimulated bite force associated with change in gape angle and bite point in a broad range of species. We focus on plant-visiting bats because they exhibit a relatively primitive cranial morphology and are good models for generalized mammals. Assessments of the relationship between gape angle and bite force within and among species demonstrate that bite force decreases significantly as gape angle increases. The relationship between bite force and bite point within each of seven species demonstrates that unilateral molar biting universally generates the highest forces while the unilateral canine biting produces the lowest forces. Bilateral canine biting is intermediate. Beyond these general patterns, differences among species suggest that bite force reflects variation in craniofacial architecture. Finally, these data suggest that behavioral variation in gape angle and bite point may be important variables in comparative, functional analyses of feeding.

Animals↗

PubMed1999

Bacteriologic analysis of infected dog and cat bites. Emergency Medicine Animal Bite Infection Study Group.

BACKGROUND AND METHODS: To define better the bacteria responsible for infections of dog and cat bites, we conducted a prospective study at 18 emergency departments. To be eligible for enrollment, patients had to meet one of three major criteria for infection of a bite wound (fever, abscess, and lymphangitis) or four of five minor criteria (wound-associated erythema, tenderness at the wound site, swelling at the site, purulent drainage, and leukocytosis). Wound specimens were cultured for aerobic and anaerobic bacteria at a research microbiology laboratory and, in some cases, at local hospital laboratories. RESULTS: The infected wounds of 50 patients with dog bites and 57 patients with cat bites yielded a median of 5 bacterial isolates per culture (range, 0 to 16) at the reference laboratory. Significantly more isolates grew at the reference laboratory than at the local laboratories (median, 1; range, 0 to 5; P<0.001). Aerobes and anaerobes were isolated from 56 percent of the wounds, aerobes alone from 36 percent, and anaerobes alone from 1 percent; 7 percent of cultures had no growth. Pasteurella species were the most frequent isolates from both dog bites (50 percent) and cat bites (75 percent). Pasteurella canis was the most common isolate of dog bites, and Past. multocida subspecies multocida and septica were the most common isolates of cat bites. Other common aerobes included streptococci, staphylococci, moraxella, and neisseria. Common anaerobes included fusobacterium, bacteroides, porphyromonas, and prevotella. Isolates not previously identified as human pathogens included Reimerella anatipestifer from two cat bites and Bacteroides tectum, Prevotella heparinolytica, and several porphyromonas species from dog and cat bites. Erysipelothrix rhusiopathiae was isolated from two cat bites. Patients were most often treated with a combination of a beta-lactam antibiotic and a beta-lactamase inhibitor, which, on the basis of the microbiologic findings, was appropriate therapy. CONCLUSIONS: Infected dog and cat bites have a complex microbiologic mix that usually includes pasteurella species but may also include many other organisms not routinely identified by clinical microbiology laboratories and not previously recognized as bite-wound pathogens.

Adolescent↗

PubMed2003

White-tail spider bite: a prospective study of 130 definite bites by Lampona species.

OBJECTIVE: To investigate the circumstances and clinical effects of bites by white-tail spiders, including the two species Lampona cylindrata and L. murina commonly encountered by humans, and the incidence of necrotic lesions. DESIGN: Prospective cohort study of definite white-tail spider bites. Cases were only included if there was a clear history of bite, the spider was caught and was identified by an expert. SETTING: Calls to Australian poisons information centres and emergency departments. PATIENTS: 130 patients with a definite bite by a white-tail spider from February 1999 to April 2002. RESULTS: There were 79 bites by L. cylindrata and 51 by L. murina. Bites occurred in warmer months, 95% indoors and 75% between 16: 00 and 08: 00. The activity at the time of the bite was characteristic and the spider was encountered between bedclothes, towels or clothing. 25% of bites occurred on distal limbs. Pain/discomfort occurred in all cases, and was severe in 27%. Other effects included puncture marks (17%), redness/red mark (83%) and itchiness (44%). Systemic effects occurred in 9%. There were no cases of necrotic ulcers (97.5% CI, 0-2.8%) or confirmed infections. Median duration of effects was 24 hours (interquartile range, 1-168 hours). There were three distinct clinical patterns: pain only (21%), pain and red mark for < 24 hours (35%), and a persistent painful or irritating red lesion (44%). CONCLUSIONS: Bites by Lampona spp. cause minor effects in most cases, or a persistent painful red lesion in almost half the cases. White-tail spider bites are very unlikely to cause necrotic ulcers, and other diagnoses must be sought.

Adolescent↗

PubMed1998

Effects on human maximum bite force of biting on a softer or harder object.

A recent study concluded that the pulps of human incisor teeth may contain mechanoreceptors. These provide the input for a protective mechanism that reflexly limits the maximum bite force by monitoring the stress on compressed dentine. In separate experiments it was later shown that individuals can accurately detect whether they are biting on a harder or softer surface when it seemed that the only receptors which could have detected the difference must have been in the tooth pulps. Thus, pulpal mechanoreceptors may be used subconsciously to limit the maximum bite force and consciously to detect differences in hardness. If these conclusions are correct the maximum bite force should be larger when incising on a soft (rubber) surface than on a hard (acrylic) surface because when the teeth sink into the rubber the bite force is spread over a larger area, thereby reducing the local stress. A reduction in stress allows an increase in bite force. But if the tooth were previously covered with an acrylic crown, which would already reduce the stress by distributing the bite force over a large area of the incisor crown, there would be little or no difference in the maximum bite force whether biting on rubber or acrylic. The results of experiments on 15 participants confirm these predictions and support the hypothesis that the pulps of human incisors contain high-threshold mechanoreceptors.

Adult↗

PubMed1987

Natural course of the human bite wound: incidence of infection and complications in 434 bites and 803 lacerations in the same group of patients.

Human bites and common lacerations are frequent in certain residential groups in institutions for the care of developmentally disabled individuals. We screened the records of such an institution and studied the course and outcome of 434 human bite wounds and 803 lacerations in the same group of clients. Infection developed in 13.4% of the lacerations, and 17.7% of the bite wounds (chi 2 = 3.474; p greater than 0.06). Prophylactic antibiotics were administered after 14.0% of the bite wounds, and 3.2% of the lacerations. Infection supervened after prophylactic antibiotics in 29.5% of the bites and 34.6% of the lacerations. No patient with a bite wound required debridement, initial or subsequent surgical intervention other than wound closure, admission to hospital, or intravenous antibiotics. There is no recorded instance of a bite wound complication other than immediate loss of tissue. These data substantiate a higher incidence of infection in human bite wounds, but they are scant support for admonition that such wounds are indication for routine antimicrobial prophylaxis or aggressive surgical intervention.

Anti-Bacterial Agents↗

PubMed2002

Bite performance in clariid fishes with hypertrophied jaw adductors as deduced by bite modeling.

Within clariid fishes several cranial morphologies can be discerned. Especially within anguilliform representatives an increase in the degree of hypertrophy of the jaw adductors occurs. The hypertrophy of the jaw adductors and skeletal modifications in the cranial elements have been linked to increased bite force. The functional significance of this supposed increase in bite force remains obscure. In this study, biomechanical modeling of the cranial apparatus in four clariid representatives showing a gradual increase in the hypertrophy of the jaw adductors (Clarias gariepinus, Clariallabes melas, Channallabes apus, and Gymnallabes typus) is used to investigate whether bite force actually increased. Static bite modeling shows that the apparent hypertrophy results in an increase in bite force. For a given head size, the largest bite forces are predicted for C. apus, the lowest ones for C. gariepinus, and intermediate values are calculated for the other species. In addition, also in absolute measures differences in bite force remain, with C. apus biting distinctly harder than C. gariepinus despite its smaller head size. This indicates that the hypertrophy of the jaw adductors is more than just a correlated response to the decrease in absolute head size. Further studies investigating the ecological relevance of this performance difference are needed.

Animals↗

PubMed1999

Comparison of biting forces in different age and sex groups: a study of biting efficiency with mobile and non-mobile teeth.

This study aimed (1) to investigate the influences of sex, age and number of teeth on biting ability through a descriptive survey, and (2) to compare the biting ability between the subjects with and without mobile teeth in a case-control study. A total of 687 subjects cooperated in the descriptive survey. Each subject bit on a pressure detecting sheet with their maximum biting force. Three indices of biting ability: biting pressure (MPa), biting force (N) and occlusal contact area (mm2) were calculated from the impressed marks on the sheet using a high vision video processor system. These indices were correlated well with the number of teeth according to the multiple regression analysis. In the case-control study, matching procedures with sex, age and number of teeth were performed between the subjects with and without mobile teeth. No differences in the three indices were observed between the two well-balanced groups. The results showed that the number of teeth is most important to maintain biting ability, and that the presence of mobile teeth does not always reduce biting ability.

Adolescent↗

PubMed1993

A novel bite force recorder and maximal isometric bite force values for healthy young adults.

Human bite forces have been studied with several types of equipment, and the maximal values reported have varied greatly. In the present study, a new bite force recorder was developed to measure human bite forces. When measuring maximal bite force, the mandible is, laterally and sagittally, almost in the intercuspal position, while the vertical opening of the jaws in the molar region is about 14 mm. Several teeth bite upon the housing. A quartz force transducer serves as a sensory unit. A microprocessor produces a numeric result, shown on a liquid crystal display (LCD). In order to adapt the sensor to be a part of a bite force recorder, we designed a unilateral housing of nonhardened tool steel. In laboratory calibration tests, a series of loads from 112.8 to 1691.5 N was used. The maximal bite forces of healthy undergraduate dental students, 15 men and 15 women, were investigated. The results for both genders remarkably exceeded the values previously reported for unilateral housings. The mean maximal bite force value in the molar region was 847 N for men and 597 N for women. The finding that pain or lack of muscular strength most often limited the clenching suggests that the actual masticatory potential was registered.

Adult↗

PubMed1999

Influence of clenching intensity on bite force balance, occlusal contact area, and average bite pressure.

It has been difficult for investigators to simultaneously and reliably evaluate bite force in the intercuspal position with the area and location of occlusal contacts. This study was designed to investigate the variations in these parameters with respect to two factors: three levels of clenching and the preferred chewing side. Human subjects with normal occlusion were examined with a recently developed system (Dental Prescale Occluzer, Fuji Film, Tokyo, Japan). The three levels of clenching intensity were assessed by masseteric EMG activity and included the maximum voluntary contraction, and 30% and 60% of the maximum. The results indicated that the bite force and occlusal contact area on the whole dental arch increased with clenching intensity. In contrast, the average bite pressure, obtained by dividing the bite force by the contact area, remained unchanged regardless of the clenching intensity. As the clenching intensity increased, the medio-lateral position of the bite force balancing point shifted significantly (P<0.01) from the preferred chewing side toward the midline. The antero-posterior position remained stable in a range between the distal third of the first molar and the mesial third of the second molar. The bite force and occlusal contact area, which were mainly on the molars, increased with the clenching intensity, whereas the proportions of these two variables on each upper tooth usually did not change significantly. The exception was the second molar on the non-preferred chewing side. When comparisons were made between pairs of specific upper teeth of same name, usually no significant difference was found in bite force or occlusal contact area, regardless of the clenching level. Again, the exception to this observation was the second molar on the preferred chewing side, which had a larger area at the 30% clenching level. The results in normal subjects suggest that as the clenching intensity increases in the intercuspal position, the bite force adjusts to a position where it is well-balanced. This adjustment may prevent damage and overload to the teeth and temporomandibular joints.

Adult↗

PubMed1993

The relationship between maximal bite force, bite force endurance, and facial morphology during growth. A cross-sectional study.

The aims of this investigation were to study the relation between facial morphology and bite force at different ages during growth and to investigate possible relations between bite force and the variables age, finger force, stature, and sex in growing healthy individuals. One hundred and thirty-six individuals were included, consisting of six groups of males and females, 7-9, 10-12, and 20-24 years old. Standardized photographs were taken to determine the facial type. The occlusal relationship, body height, finger force, maximal bite force, and bite force endurance amplitude were recorded. All bite force variables and finger force increased with age in both sexes. A positive correlation was found between the maximal bite force in the incisor region and the ratio of upper to lower facial height; this is, subjects with a high bite force had a relatively short lower anterior height. The maximal bite force for molars and endurance amplitude were positively correlated to stature and finger force but not to facial characteristics. A longitudinal study to follow each individual child during growth would be of interest to evaluate the importance of muscular influence on facial growth.

Adult↗

PubMed1998

Studies on biting density and biting cycle of Culex quinquefasciatus, say in Khon Kaen City, Thailand.

Biting density and biting cycle of Culex quinquefasciatus in Khon Kaen City were examined during November 1994 to October 1995. Biting activity of the mosquito was assessed by using the indoor human bait method. Trapped mosquitos were identified and carefully dissected to determine their parities. Climatory data ie temperature, relative humidity and rainfall were also recorded during the study. The densities of mosquito ranged from 1.6/man/hour in December to 9.2/man/hours in March with the average of 5.0/man/hours. The lowest biting density was observed in winter and higher densities were in summer and rainy seasons. The temperature was the most important variable that influenced the biting density in each month of the year (p<0.05). The biting cycle showed that the mosquito active throughout the night, with peak activity at 22.00-23.00 hours. Parous rate of the mosquito ranged from 33.3% in February to 71.9% in November with the average of 47.3%. The biting proportion of parous mosquitos was high during the early hours of the night and gradually decreased until 06.00 hours, whereas that of the nulliparous mosquitos showed an increasing trend from 18.00 to 06.00 hours. The biting cycle of the parous mosquito reached the peak activity at 21.00-22.00 hours, 1 hour ahead of the peak for nulliparous mosquito. These findings suggested that Cx. quinquefasciatus in Khon Kaen City may be able to transmit bancroftian filariasis if they were exposed to microfilaria carrier individuals.

Animals↗

PubMed1984

Contributions of obesity, gender, hunger, food preference, and body size to bite size, bite speed, and rate of eating.

College students ate two high preference or two low preference doughnuts under high or low hunger conditions. Subjects were led to believe that we were interested in preference ratings made after eating the doughnuts. The number of bites and the total snack time were covertly recorded. Having weighed the doughnuts previously, we calculated the bite size (amount per bite), bite speed (time per bite), and eating rate (amount per second). Eating rate increased as obesity, body size, hunger, and preference increased; men ate at a faster rate than women. Larger bites accounted for the increased rate of the obese, the high preference subjects, and those having a larger body size. The hungry subjects increased their eating rate by taking faster bites. Men ate faster than women by taking both larger but slower bites. Thus eating rate is under multiple control. The data also suggest that the effects of obesity and, in part, gender on these eating responses may be more parsimoniously explained as body size effects. Modification of these within-session eating responses in order to regulate food intake will be successful only when the relationships among these measures are understood.

Adolescent↗

PubMed1997

Comparison of the effects of passive posterior bite-blocks with different construction bites on the craniofacial and dentoalveolar structures.

Posterior bite-blocks that are used in the early treatment of skeletal open bite, produce a forward and upward mandibular rotation by transmitting the masticatory muscle forces to the buccal dentoalveolar regions and preventing their vertical growth. Increasing the vertical dimension of the face artificially causes skeletal adaptations to occur not only in the dentoalveolar region but also in the other regions of the craniofacial complex. The affects of passive posterior bite-blocks, constructed in two different heights, were investigated for two treatment groups, in comparison to an untreated control group. Two treatment groups comprised of 25 growing patients, who had skeletal open bite and skeletal/dental Class I or Class II malocclusions, and one control group consisting of 14 growing patients were used. These groups were matched concerning their age, sex, and vertical and sagittal skeletal cephalometric and dental characteristics. Passive posterior bite-blocks of 5 and 10 mm heights were applied to the subjects of the treatment groups respectively for 18 hours per day. Untreated control subjects were observed for 7 to 9 months. The findings of this study revealed that the downward and backward mandibular rotation continued in the control group, increasing the lower facial height significantly, whereas in the treatment groups, the skeletal open bite was treated and the mandible rotated upward and forward. The increase of the height of the posterior bite-blocks had a significant effect on the anterior mandibular rotation and in the increase of the gonial angle.

Adolescent↗

PubMedDate not supplied

Rat bites support need for in-home control: an epidemiologic study of rat bites in New York City, 1974-1978.

Rat bite reports in New York City during the years 1974-1978 were analyzed by time, place and person characteristics. Rat bites showed a general decline over the five-year period, from 226 reported bites in 1974 to 162 reports in 1978 (2/100,000 population). The decrease in reported bites from areas with active rodent control programs was twice the decrease from areas without such programs. The highest rates were reported from the health districts of the Lower East Side of Manhattan and the Williamsburg-Greenpoint section of Brooklyn. Rat bite rates in reported incidents are highest in children under age five, with no significant difference between sexes. Of the 1069 reported rat bites for the five-year period, 41.4% occurred on the hand, particularly the fingers, and 87.9% occurred indoors. The use of rat bite reports is a mechanism to identify high risk groups and areas of rodent infestation as well as indicating the success of rodent control programs.

Age Factors↗

PubMed1995

Venomous snake bite without clinical envenoming ('dry-bite'). A neglected problem in Brazil.

Venomous snake bite without envenoming ('dry-bite') has been recognized throughout the world, but neglected in the Brazilian literature. Forty cases of patients bitten by venomous snakes of the genera Bothrops (lance-headed vipers) and Crotalus (South American rattlesnakes), confirmed by identification of the captured or dead snake, were seen in a 34-month prospective study carried out in a teaching hospital in southeastern Brazil. Out of the 33 cases of lance-headed viper and 7 of rattlesnake bite, respectively 10 (30.3%) and 3 (42.9%) had no clinical or laboratory evidence of local or systemic envenoming. Both within the Bothrops and Crotalus groups, there was no significant difference in sex and age of the patients, and time between bite and medical assistance between the patients who had from those who did not have clinical envenoming. The high prevalence of 'dry-bite' in this study may have several possible explanations, and has implications on the indication of antivenom for the treatment of venomous snake bite. Antivenom administration may be postponed or even not indicated for victims of snake bite presenting no manifestations of local or systemic envenoming.

Adolescent↗