PubMed Health⌕ Search

Biomedical subjects

B Ingervall

Publications and source records attributed to B Ingervall.

At least 19 recordsLinked to original sources
PubMed2000

The effect of a maxillary lip bumper on tooth positions.

The effect of the use of a lip bumper with anterior vestibular shields on the maxilla was studied in twenty-two 9-14-year-old children with a space deficiency in the maxillary dental arch. The lip bumper was used for 1 year. The effect of the treatment was evaluated from dental casts and profile cephalograms made before and after treatment. Both the width of the maxillary dental arch at the premolars and the length of the arch increased significantly by about 2 mm. The effect of the treatment on the antero-posterior position of the first molars was small. In one subject the molar was distalized 2.8 mm. The average effect was, however, a reduction in the anterior movement of the molar within the face by about 0.5 mm, i.e. the maxilla moved anteriorly 1 mm, but the molar only 0.4 mm. No skeletal effects were found when the group of subjects treated with a lip bumper was compared with a reference sample of untreated individuals. The main effects of a maxillary lip bumper thus seem to be a widening of the dental arch across the premolars, a moderate increase in arch length due to eruption and slight proclination of the incisors, and moderate distal tipping of the first molars.

Adolescent↗
PubMed1999

Treatment results in dental school orthodontic patients in 1983 and 1993.

The effect of incremental changes in materials and techniques on orthodontic treatment outcomes is difficult to evaluate objectively. Treatment results for two groups of patients whose treatments were completed approximately 10 years apart were evaluated using the peer assessment rating (PAR) index and the index of orthodontic treatment need (IOTN) using the Wilcoxon matched-pairs signed-rank test. Patients in the later group who had been treated by postgraduate students primarily (using fixed appliances) had significantly lower IOTN and PAR scores at the end of treatment and showed a significantly greater reduction in the PAR score than a similar group of patients in the earlier group. There were no significant differences in treatment results between patients in the early and late groups who were treated with removable appliances. Differences in treatment results were most likely the result of changes in materials and techniques that had occurred in the 10 intervening years.

Adolescent↗
PubMed1999

Pressure from the lips on the teeth during speech.

Pressure on the teeth from the labial soft tissues during the articulation of a given sentence was measured in 24 children, 8 to 14 years old, with normal incisor relationships. The points of measurement were labial in the midlines between the maxillary and mandibular central incisors and between the right maxillary canine and first premolar (the modiolus point). A mouthpiece was attached to the teeth at these three positions and connected via a water-filled system to an extraoral pressure transducer. A microphone recorded the volume and speed of articulation while the activity of the lip muscles was surveyed by electromyography. The maximal pressure during pronunciation of the consonant /p/, the pressure at rest (RP), the speech posture pressure (SPP), the time pressure integral (TPI), and the mean speech pressure (MSP) during articulation were analyzed. Maximal pressure during pronunciation of /p/ and TPI were highest at the modiolus, second highest at the lower midline, and lowest at the upper midline. RP and SPP were highest at the lower midline. SPP was 2 to 3 times higher than RP, and MSP was 4 to 7 times higher than RP. The pressures during articulation recorded at the lower midline were closely correlated with those at the modiolus, with weaker correlations between the upper and lower midlines and between the upper midline and modiolus. There was a close correlation between RP and SPP. SPP, MSP, and TPI may, along with RP, contribute to the positions of the teeth.

Adolescent↗
PubMed1999

Cheek and tongue pressures in the molar areas and the atmospheric pressure in the palatal vault in young adults.

The pressures acting on the maxillary and mandibular posterior teeth from the tongue and cheeks were measured in 24 adults aged 22-29 years. In addition, the pressure in the palatal vault was recorded. The pressure at two maxillary (buccal and lingual) and two mandibular (buccal and lingual) measuring points, and in the palatal vault was recorded simultaneously. Repeated recordings of the pressures at rest, and during chewing and swallowing were made. The pressures at rest were of similar magnitude (about 2 g/cm2) at the buccal and lingual sides of the mandibular posterior teeth. The median resting pressure at the maxillary posterior teeth was 2.7 g/cm2 on the buccal side and 1.0 g/cm2 on the lingual side. The difference in the maxilla was significant, but not in the mandible. It was concluded that the equilibrium of tooth position is maintained by the pressure from the cheeks and the tongue. During chewing and swallowing the pressures on the lingual side of the teeth were greater than those on the buccal side. At rest about half of the subjects had a negative pressure at the palatal vault, but no correlations between the resting pressure at the palatal vault and the resting pressures on the teeth were found.

Adult↗
PubMed1998

The use of the Jasper Jumper for the correction of Class II malocclusion in the young permanent dentition.

The effect of the Jasper Jumper in the treatment of Class II, division 1 malocclusions was studied in 26 consecutive 13-25-year-old patients. The median treatment time was 5 months, followed by a median period of observation or retention of 7 months. The effects of the treatment were evaluated from cephalograms taken before the treatment, at the removal of the Jumpers and at the end of the period of observation or retention. The Jumpers brought about a slight retrusion of the maxilla and markedly increased the mandibular prognathism. The maxillary incisors and molars were retruded, and the mandibular incisors and molars protruded. The median correction of the overjet was almost 5 mm and of the molar relationship 3 mm. The intrusive forces of the Jumper resulted in a transient intrusion of the maxillary molars and the mandibular incisors. After the period of retention and observation, the dento-alveolar effects had partially or totally relapsed. The remaining effect contributing most to the correction was the skeletal effect on the mandible, i.e. the increase in mandibular prognathism. The skeletal mandibular effect was the same in younger and older subjects. At the end of observation about 60 per cent of the overjet reduction and 75 per cent of the molar correction remained. The incidence of breakage of the Jumpers was 9 per cent.

Activator Appliances↗
PubMed1998

The initial effects of the treatment of Class II, division 1 malocclusions with the van Beek activator compared with the effects of the Herren activator and an activator-headgear combination.

The effects of the van Beek activator in the correction of Class II, division 1 malocclusions were studied in 39 children, aged 9-13 years (median 11 years), and compared with the effects of treatment with an activator according to Herren and with those of an activator-headgear combination. Profile cephalograms were made before treatment and at the attainment of a Class I molar relationship (median observation time 9 months). The median improvement of the overjet was 4.7 mm and of the molar relationship 3.6 mm. This was largely achieved skeletally by in increase in mandibular prognathism while the skeletal effect on the maxilla was clinically insignificant. The maxillary incisors retroclined and the mandibular incisors proclined moderately. In general, no intrusion of the maxillary incisors was found and the eruption of the molars could not be stopped. The effects differed partly between the sexes, with a larger mandibular skeletal and molar reaction in the boys and a larger maxillary molar movement in girls. The larger mandibular reaction in the boys might have been due to the on average 4.5 months longer treatment time. The skeletal effects of the treatment were similar with all three activator types. The control of the incisors was, however, superior with the van Beek activator, especially when compared with the Herren activator.

Activator Appliances↗
PubMed1998

No effect of lip bumper therapy on the pressure from the lower lip on the lower incisors.

The pressures from the lower lip on the lower incisors were measured at the midline between the central incisors and between the left lateral incisor and canine. The measurements were made with the lip at rest and during swallowing of water in 24 boys and 40 girls aged 9-15 years. The children were divided into four groups, two treated with a lip bumper with and without an oral shield, and two with a lingual arch with and without springs for proclination of the lower incisors. Recordings of the pressures were made before the start of the treatment, and 3 and 8 months after the use of the appliance, as well as 4 months after the removal of the lip bumper or lingual arch. The treatment with a lip bumper did not change the pressure from the lip on the lower incisors at rest. The pressure at the midline during swallowing was also unaffected by the lip bumper therapy, but the pressure between the lateral incisor and canine increased. Thus, lip bumper therapy did not lead to decreased pressure from the lip on the incisors. Proclination of the lower incisors with a lingual arch resulted in an increase of the pressure from the lip at rest. Thus, no adaptation of the lower lip to the proclination occurred. After relapse of the proclination the pressure from the lip decreased to a value no different from that before the start of the treatment.

Acrylic Resins↗
PubMed1997

Initial effects of treatment of Class II malocclusion with the Herren activator, activator-headgear combination, and Jasper Jumper.

The initial effects of treatment of Class II, Division 1 malocclusion with an activator, according to Herren (27 patients), with an activator-headgear combination (20 patients), or with the Jasper Jumper appliance (25 patients) were studied on lateral cephalograms from before and after 6 to 8 months of treatment. The patients' ages ranged from 9 to 12 years. At the end of the period of observation, the correction in overjet and molar relationship was more complete in the patients with the Jasper Jumper than in the patients with the activator. Whereas all the patients with the Jasper Jumper showed neutral occlusion, this was the case in only 20 of the 47 patients with the activator. The correction of the distal occlusion occurred through a combination of skeletal and dentoalveolar adaptations. Skeletal changes accounted for 42%, 35%, and 48% of the overjet correction by the Herren-type activator, the headgear-activator, and the Jasper Jumper, respectively. The correction of the molar relationship occurred to 55%, 46%, and 38% by skeletal changes in the respective groups. Dentoalveolar compensation (distal movement of the upper molars, mesial movement of the lower molars) appeared to be inversely related to skeletal adaptation. The patients with the Jasper Jumper showed a marked intrusion of the lower incisors with a consequent reduction in overbite.

Activator Appliances↗
PubMed1997

Correlation between maximum bite force and facial morphology in children.

The correlation between maximum bite force and facial morphology was studied in 54 boys, 8 to 16 years old, and 66 girls, 7 to 17 years old. Bite force was measured at the first molars with a miniature bite force recorder. Facial morphology was evaluated on profile cephalograms. In addition, the number of teeth in contact in the intercuspal position was recorded with occlusal foils. In the girls, maximum bite force was correlated with the inclination of the mandible, the size of the gonial angle, and the ratio between posterior and anterior face heights. The correlations implied a large bite force with a small mandibular inclination and gonial angle, a large posterior face height in relation to the anterior face height, and a small bite force with the opposite facial characteristics. These correlations were nonexistent or weaker in boys. In both sexes, bite force was correlated with the number of occlusal contacts. Elimination of the influence of age and occlusal contact in the group of girls by the use of partial correlations reduced the correlation between bite force and facial morphology. A significant correlation with the size of the gonial angle remained, however, and the correlation with mandibular inclination was close to significance. In addition to the correlations found with facial morphology, the study clearly demonstrated the need to take gender and occlusal contacts into consideration in future studies of masticatory muscle function and strength in relation to facial morphology.

Adolescent↗
PubMed1997

A clinical comparison of the rate of maxillary canine retraction into healed and recent extraction sites--a pilot study.

The rate of movement of the maxillary canines into the healed or recent extraction alveolus of the first premolar was measured in 22 patients aged 10-27 years. On one side of the dental arch, the first premolar was extracted. After a median time of 86 days, the contralateral first premolar was extracted and the distalization of both canines started using Gjessing canine retraction springs. The experiment was ended when one of the two canines had been sufficiently distalized. Recordings of the positions of the canines at the beginning of the study, at the start of the distalization and at the end were made from dental casts and standardized intraoral radiographs. The canine on the recent extraction side moved faster than that on the healed side, but also tipped somewhat more. The reasons for the increased tipping and the faster movement are discussed.

Adolescent↗
PubMed1996

Moments and forces delivered by transpalatal arches for symmetrical first molar rotation.

The moments and forces delivered by round transpalatal arches of steel and of beta-titanium (TMA) for symmetrical derotation of molars were studied in laboratory experiments. Three sizes of arches were tested in two series. In the first series, the degree of activation was checked for symmetry in a computer-based strain-gauge measuring system. In the second series, the activation was carried out in a way simulating clinical use. The mesio-distal and transverse forces and the derotating moments at full activation and during derotation in steps of 5 degrees were measured. At full activation, the steel arches delivered relatively large moments which, however, decreased rapidly during deactivation. The TMA arches had a larger working range. It was not possible to achieve full symmetry of the moments at the two ends of the arch. The difference of the two moments resulted in forces acting on the two anchorage teeth in a mesio-distal direction. These forces were generally small but could reach clinically relevant magnitude. The derotation resulted in a contractive force of up to 2.7 N which has to be compensated for by expansion. The mode of activation simulating clinical use resulted in reasonably constant forces and moments. The use of a vice to hold the arch during activation was found to be of great help and is recommended in the clinical setting. Because of the larger working range, TMA arches are recommended if substantial derotation is needed.

Adolescent↗
PubMed1996

The effect of a transpalatal arch for the correction of first molar rotation.

The effects of a transpalatal arch for the symmetrical derotation of rotated first molars were evaluated in 50 children, 8-13 years of age. The positions of the molars were compared with those in 34 individuals, aged 12-18 years, with normal occlusion. Prefabricated (GAC) stainless steel arches were used for 60-198 days (median time 122 days). The effect was recorded with a measuring microscope on dental casts from before and after the treatment. Molar positions were determined from the tips of the four cusps of the tooth in relation to a coordinate system based on palatal reference points. The centre of rotation of the molars during derotation were calculated from the movement of their cusps. Before derotation the first molars were significantly mesiopalatally rotated compared with the normal occlusion group. The derotation overcompensated the initial rotation. In about two-thirds of the cases the mesiobuccal cusp of the molar moved distally during the derotation. In the remaining cases it moved mesially or remained unchanged. The median distal movement was 0.3 mm on the right and 0.5 mm on the left side. Because many molars moved mesially, on average there was no gain in space in the dental arch from the derotation. The location of the centre of derotation varied widely but it was on average located midway between the distobuccal and distopalatal cusps. In most cases the derotation resulted in a small, unintended, expansion. The study showed that mesiopalatally rotated first molars can effectively be derotated with a transpalatal arch. The effect on the mesiodistal position of the mesiobuccal cusp, and particularly with regard to space gain, is, however, unpredictable.

Adolescent↗
PubMed1995

A clinical investigation of the correction of unilateral first molar crossbite with a transpalatal arch.

The correction of a unilateral first molar crossbite with a Goshgarian type of transpalatal arch was evaluated in 35 children from 6 years, 8 months to 15 years, 11 months old. Fifteen of the children were treated with an arch activated for expansion only and 20 children with an arch activated in a similar way but with the inclusion of buccal root torque of the anchorage tooth. With both types of activation, the arches worked in a statically determinate system, i.e., the tooth in crossbite was allowed to tip buccally. The movements of the first molars as a result of the treatment were monitored by measurements on dental casts and frontal cephalometric roentgenograms. In addition, the width of the midpalatal suture was measured on occlusal roentgenograms of the maxilla. In the children treated with an arch activated only for expansion, the molars on both sides of the dental arch moved buccally during the treatment. In the children treated by torque activation, on the other hand, there was a considerable buccal movement of the molar on the side of the crossbite without any significant buccal movement of the anchorage tooth. In individual cases, the molar on the noncrossbite side moved and tipped palatally and in some cases buccally but to a minor degree. With both types of activation, there was only a slight change in inclination of the transverse occlusal plane through the first molars; the plane opened up slightly toward the side of the crossbite. For both types of activation, there was a slight widening of the palatal suture during the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

The effect of a lip bumper on lower dental arch dimensions and tooth positions.

The effect of a lip bumper on the dimensions of the lower dental arch and on the inclination of the incisors and first molars was studied in 40 children, aged 9-12 years. The children wore their lip bumper full time for 7-10 months. The effects of the lip bumper therapy were recorded on dental casts and profile cephalograms made before and after the treatment. The positions and stages of development of the lower second molars were determined on pretreatment intra-oral radiographs. The lip bumper treatment resulted in an increase of the dental arch widths between the molars, premolars, and canines. The arch length increased through proclination of the incisors and uprighting of the first molars. The stages of development and the positions of the second molars had no influence on the effect of the treatment. Simultaneous treatment in the maxilla with a headgear, a transpalatal arch or a removable plate had no influence on the outcome of the lip bumper therapy.

Cephalometry↗
PubMed1995

Stability and effect on the soft tissue profile of mandibular setback with sagittal split osteotomy and rigid internal fixation.

The stability and the effect on the soft tissue profile of mandibular setback with sagittal split osteotomy and rigid internal fixation was studied prospectively in 29 consecutive patients, 17 to 55 years old, who had mesial occlusion. Profile cephalometric radiographs were taken immediately before and short after surgery as well as 14 months postsurgically. The mean setback of the mandible 1 to 8 days after surgery was 6.0 mm. On average, there was also a small decrease in the anterior facial height. The setback relapsed an average of 1.1 to 1.3 mm, so that at the follow-up the mean net effect was 80%. In eight patients, however, the mandible had retruded slightly further. During the follow-up period there was a further small decrease in the anterior facial height. The net effects on the labial fold and the soft tissue chin were closely correlated with those on their underlying hard structures. On average, the labial fold and the chin followed the hard structures to 106% and 107%, respectively. The mean net effect for the lower lip was only 88% of the setback of the mandibular incisor. The soft tissue facial height followed the decrease in the skeletal facial height to 60%. The setback procedure also affected the upper lip, which, on average, retruded and lengthened 1.0 to 2.0 mm.

Adolescent↗
PubMed1994

Stability and effect on the soft tissue profile of mandibular advancement with sagittal split osteotomy and rigid internal fixation.

The stability and the effect on the soft tissue profile of mandibular advancement with sagittal split osteotomy and rigid internal fixation was studied prospectively in 30 consecutive patients, 17 to 32 years old, who had a distal occlusion. Profile roentgen cephalometric recordings were made immediately before and shortly after surgery as well as 13 months postsurgically. The mean advancement of the mandible 3 to 8 days after surgery was 5 mm. On average, there was only a small increase in the anterior facial height. At the follow-up after 13 months, the advancement of the mandible had, in most cases, partially relapsed so that the median net effect was 70%. In six subjects, however, the mandible had advanced slightly further. The skeletal relapse was partially masked by compensatory movements of the maxillary incisors so that the mean net effect on the overjet was 83%. The amount of relapse was positively correlated to the magnitude of advancement during surgery. Likewise, a postsurgical relapse of the anterior facial height was positively correlated to the magnitude of advancement during surgery. Likewise, a postsurgical relapse of the anterior facial height was positively correlated to the magnitude of the vertical surgical displacement anteriorly and posteriorly. The soft tissue chin closely followed the underlying hard tissue. The mean net effect on the labial fold, however, was smaller, 88% of the mandibular advancement. The net effect on the lower lip was 66% of the advancement of the mandibular incisor.

Adolescent↗