Effects of masticatory muscle training on maximum bite force and muscular endurance.

OBJECTIVE: This study evaluates the effects of chewing training on strength and endurance of the masticatory muscles. MATERIALS AND METHODS: Of the 49 healthy young adults included in the study, nine served as controls for a baseline measurement of bite force. The 40 participants who actively trained their masticatory muscles were randomly divided into a 'continuous training group' (CTG) and an 'intermittent training group' (ITG). The participants performed oral motor training by clenching silicon tubes (Chewy Tubes(™)) according to a designed protocol. The muscular strength was studied in terms of maximum bite force. Muscular endurance was evaluated by measuring the duration for which the participants held 50% of their maximum bite force value. RESULTS: Both the maximum bite force and the muscular endurance capacity increased after intensive training for both groups. After 2 months, the ITG stopped training for 1 month. At this point, a significant difference was identified both in the mean bite force values and the mean muscular endurance duration: the ITG exhibited lower values. For both groups, the highest values were attained after 3 months of training. The maximum bite force values and the muscular endurance duration were observed to follow similar patterns. The effects attained decreased rapidly in both groups when the training stopped. CONCLUSIONS: For both the continuous and intermittent training groups, 4 months of chewing exercises strengthened masticatory muscles, but such effects diminished gradually for both groups when the exercises stopped.

Comparing patients with Apert and Crouzon syndromes--clinical features and cranio-maxillofacial surgical reconstruction.

Cranio-maxillofacial malformations, as seen in Crouzon and Apert syndromes, may impose an immense distress on both function and aesthetics of the person affected. The aims of this study were to describe and compare the main facial and intraoral features of patients with Apert and Crouzon syndromes, the clinical manifestations that may be present, additionally to the main syndromic traits, as well as the cranio-maxillofacial surgical treatment protocols followed.Twenty-three patients with Apert syndrome (6 males, 17 females), and 28 patients with Crouzon syndrome (20 males, 8 females) were evaluated for general medical aspects, craniofacial characteristics, dentoalveolar traits before and after the final orthognathic surgery, and types and timing of cranio-maxillofacial operations. Mental retardation, associated additional malformations, cleft palate, and extensive lateral palatal soft tissue swellings were more common in children with Apert syndrome. In both syndromes, clinical findings included concave profile, negative overjet, posterior crossbites, anterior openbite, and dental midline deviation, which were corrected in almost all cases with the final orthognathic surgery, with the exception of the lateral crossbites, including more than one tooth pair, which were persisting in about half of the cases. Cranial vault decompression and/or reshaping, midfacial and orbital advancement procedures, often in conjunction with a mandibular setback, were the most frequent cranio-maxillofacial operations performed. In conclusion, Apert syndrome is more asymmetric in nature and a more severe clinical entity than Crouzon syndrome. The syndromic dentofacial features of both conditions could be significantly improved after a series of surgical procedures in almost all cases with the exception of the posterior crossbites, with haIf of them persisting post-surgically.

Esthetic views on facial and dental appearance in young adults with treated bilateral cleft lip and palate (BCLP). A comparison between professional and non-professional evaluators.

The aim of the present study was to make a comparison between the professional and non-professional evaluations concerning the esthetic outcome after the completion of patients who have been treated for bilateral cleft lip and palate. A web-based questionnaire, with 12 photo sets, was answered by 25 orthodontists and 20 young adults who had been treated with orthodontic fixed appliances. They ranked the three first features they noticed when looking at each photo set, and then rated specific variables as being bad, fairly good, good, or excellent. At the end of each set, they had an opportunity to add any additional comments. The three features first noticed by the orthodontists were 'the upper lip', 'the nose' and 'the scar'. The young adults reported first 'the teeth', 'the upper lip' and 'occlusion/alignment of the teeth'. The specific variables similarly rated by orthodontists and young adults were 'the profile of the face', 'the form of the upper lip' and 'the entire facial appearance'. The orthodontists were less critical than the young adults concerning 'the upper teeth alignment', 'the lower teeth alignment', 'shape of the upper teeth', and 'color of the upper teeth'. The individual opinion on each separate set of photos was additionally important in explaining the rating, regardless the category of being either orthodontists or young adults.

Dental agenesis patterns of permanent teeth in Apert syndrome.

Dental agenesis may either occur as an isolated trait (non-syndromic) or as a component in a congenital syndrome. The aim of the present study was to identify the prevalence of dental agenesis for each type of tooth and to look for dental agenesis patterns in persons with Apert syndrome. Serial panoramic radiographs of 23 individuals (five male patients and 18 female patients) were examined. Third molars were excluded. The prevalence of agenesis for at least one tooth was 34.8%. Up to two missing teeth were found for individuals with Apert syndrome. Maxillary lateral incisors and mandibular second premolars were the most frequently missing teeth. Four different dental agenesis patterns of the entire dentition were identified by using the tooth agenesis code (TAC). Two patterns occurred more frequently, both of which were symmetrical. One involved the simultaneous absence of teeth 12 and 22, and the other showed agenesis of teeth 35 and 45. In conclusion, patients with Apert syndrome were found to exhibit a high prevalence of dental agenesis. All dental agenesis patterns in which more than one tooth was missing were symmetrical.

Living with Crouzon syndrome: how do young adults with Crouzon syndrome handle their life situation?

BACKGROUND: Recent research has been focused on those attributes that appear to buffer a person against the stresses and strains of living with a visible difference. AIM: To provide some insight on how young adults with Crouzon syndrome handle their life. DESIGN: Telephone interviews were carried out with eight Crouzon syndrome individuals (six males, two females, mean age 25.4 years) and data were analysed according to the qualitative method of grounded theory. RESULTS: The informants' main concern was to make the best of their situation, showing that even in adverse conditions, as in Crouzon syndrome, several individuals do find ways to live with their difference and to succeed in various aspects of life, using strategies they construct. Such strategies, as identified from the present investigation, were labelled: committed to an engaging activity, avoiding exposed situations, actively launching oneself, struggling with normalizing facial appearance, and lowering the expectations of finding a love partner. CONCLUSIONS: The adaptation of successful coping strategies seemed to be crucial in the quest of attainment of higher self-esteem. The more the participants in the study used the coping strategies they had developed over time, the better they handled their life situation, which led to enhanced well-being.

A new yardstick for rating dental arch relationship in patients with complete bilateral cleft lip and palate.

OBJECTIVE: To develop yardsticks for assessment of dental arch relationship in young individuals with repaired complete bilateral cleft lip and palate appropriate to different stages of dental development. PARTICIPANTS: Eleven cleft team orthodontists from five countries worked on the projects for 4 days. A total of 776 sets of standardized plaster models from 411 patients with operated complete bilateral cleft lip and palate were available for the exercise. STATISTICS: The interexaminer reliability was calculated using weighted kappa statistics. RESULTS: The interrater weighted kappa scores were between .74 and .92, which is in the "good" to "very good" categories. CONCLUSIONS: Three bilateral cleft lip and palate yardsticks for different developmental stages of the dentition were made: one for the deciduous dentition (6-year-olds' yardstick), one for early mixed dentition (9-year-olds' yardstick), and one for early permanent dentition (12-year-olds' yardstick).

Dental agenesis patterns in Crouzon syndrome.

Dental agenesis may be present in an isolated familiar manner, or occur as a part of a syndrome.To date, this clinical trait seems to have been overlooked in patients with Crouzon syndrome.The aim of the present study was to investigate dental agenesis and dental agenesis patterns in a population of persons with Crouzon syndrome in Sweden. Serial panoramic radiographs of 26 individuals with Crouzon syndrome (20 males, 6 females) were examined.Third molars were excluded from the assessment. The prevalence of agenesis for at least one tooth was 42.3%. Each affected patient was found to have up to 5 missing teeth. Upper and lower second premolars were the most frequently congenitally missing teeth. Eleven dental agenesis patterns of the entire dentition were identified, as described by the tooth agenesis code (TAC). All patterns were unique and asymmetric,with only one exception, a symmetric pattern of the maxillary and mandibular second premolars. In conclusion, persons with Crouzon syndrome were found to have a high prevalence of dental agenesis and a remarkable variability of dental agenesis patterns. It is important to be aware of this clinical situation, especially when orthodontic treatment planning for these patients is performed as early as in the mixed dentition.

Dental appearance, with focus on the anterior maxillary dentition, in young adults with bilateral cleft lip and palate (CLP). A follow up study.

Bilateral CLP interferes with both facial and dental development. Surgical and orthodontic treatments help in optimizing facial and dental appearance. In order to improve the quality of treatment one of the keys is to evaluate the physical outcome. The aim of the present study was to evaluate the longitudinal treatment results in young adults born with a bilateral CLP during 1975-1991 in the south-west region of Sweden. Records and casts (13, 16 and 19 years) were evaluated for 35 persons with total bilateral CLP:s. They all belonged to the CLP team of Gothenburg. Occlusion, congenitally missing laterals, peg shaped laterals, impacted canines, midline, implants, prosthetic treatment and maxillofacial surgery were among the recorded variables. Unilateral or bilateral missing laterals were common (40%) as were peg shaped laterals (40%). Six children had impacted canines. A good symmetry and a straight midline between jaws were found after treatment for 60% of the young adults. It was more common to have canines positioned in the region for a missing or extracted lateral compared to having the lateral replaced with an implant or other prosthetic treatment. Asymmetrical maxillary frontal appearance and an acceptable occlusion are not always achieved. Awareness of and effort to solve this problem are important in reducing factors that are likely to negatively affect the harmony of the face.

A longitudinal three-center study of dental arch relationship in patients with bilateral cleft lip and palate.

OBJECTIVE: To compare and evaluate longitudinally the dental arch relationships from 4.5 to 13.5 years of age with the Bauru-BCLP Yardstick in a large sample of patients with bilateral cleft lip and palate (BCLP). DESIGN: Retrospective longitudinal intercenter outcome study. PATIENTS: Dental casts of 204 consecutive patients with complete BCLP were evaluated at 6, 9, and 12 years of age. All models were identified only by random identification numbers. SETTING: Three cleft palate centers with different treatment protocols. MAIN OUTCOME MEASURES: Dental arch relationships were categorized with the Bauru-BCLP yardstick. Increments for each interval (from 6 to 9 years, 6 to 12 years, and 9 to 12 years) were analyzed by logistic and linear regression models. RESULTS: There were no significant differences in outcome measures between the centers at age 12 or at age 9. At age 6, center B showed significantly better results (p=.027), but this difference diminished as the yardstick score for this group increased over time (linear regression analysis), the difference with the reference category (center C, boys) for the intervals 6 to 12 and 9 to 12 years being 10.4% (p=.041) and 12.9% (p=.009), respectively. CONCLUSIONS: Despite different treatment protocols, dental arch relationships in the three centers were comparable in final scores at age 9 and 12 years. Delaying hard palate closure and employing infant orthopedics did not appear to be advantageous in the long run. Premaxillary osteotomy employed in center B appeared to be associated with less favorable development of the dental arch relationship between 9 and 12 years.

Cleft extension and risks of other birth defects in children with isolated cleft palate.

OBJECTIVE: To study the risks of having other birth defects in children born with an isolated cleft palate (iCP) when the length of the cleft was taken into account. The hypothesis was that a newborn with an extensive cleft lesion may have an increased risk of other birth defects compared to a child with a less extensive cleft of the palate. MATERIAL AND METHODS: All Caucasian children with iCP born between 1975 and 2005 in the southwestern region of Sweden were included. Data were collected from standardized medical records and the length of the cleft was checked on the pre-surgical dental cast for each child. RESULTS: A total of 343 children were born with an iCP. The incidence was 0.64/1000 live births. Thirty-four percent of children with either a total or partial iCP had other birth defects. The risk was 1.7 times higher for a total compared to a partial iCP. The two most common birth defects were congenital heart disease and intellectual disability. Ear problems related to infections were registered in 43% of cases. Fifteen percent of the children had the Pierre Robin sequence, which was analyzed as a separate variable and not included as a birth defect. CONCLUSIONS: The length of the iCP was found to influence the risk of having another birth defect as the total palatal clefts were more often combined with other birth defects compared to partial clefts. Careful medical check-ups are important for newborns with iCP since they have increased risks of other birth defects.

Orthognathic surgery in patients with craniofacial syndrome. I. A 5-year overview of combined orthodontic and surgical correction.

We studied orthognathic correction of dentofacial deformities in patients with craniofacial syndromes (Crouzon, Apert, and Treacher Collins) during a 5-year period. The number of patients treated within this time period was 17 with Crouzon syndrome, 12 with Apert syndrome, and six with Treacher Collins syndrome. Individual follow-up was 2.5 years. Bimaxillary operation, sometimes with genioplasty, has been done after preoperative orthodontic treatment of 1.5-2.5 years. Clinical and radiographic cephalometric evaluations of the orthodontic results were made. The functional and aesthetic results were satisfactory in most patients, although there were large individual variations. The experience of a craniofacial centre such as the one in Gothenburg, Sweden, which has different odontological and medical specialities, is invaluable for an optimal result.

Aspects on dental hard tissues in primary teeth from patients with Ehlers-Danlos syndrome.

BACKGROUND: Ehlers-Danlos syndrome (EDS) is a rare hereditary condition affecting connective tissues and dental hard tissues. HYPOTHESES: Primary enamel and dentine from EDS patients were expected to differ from those of healthy subjects regarding morphology and chemical composition. DESIGN: Forty-seven exfoliated primary teeth from 25 patients with EDS were investigated. Morphology was studied using a polarized light microscope, scanning electron microscope, and X-ray microanalysis. Comparisons were made with 36 primary teeth from 36 healthy patients. RESULTS: Morphological analysis of enamel in EDS teeth showed a high frequency of postnatally hypomineralized enamel and postnatally located incremental lines, whereas dentine was normal in all patients. Chemical analysis could not reveal any differences between EDS and control patients except for lower content of C and a higher Ca/P ratio in the enamel in the EDS teeth, indicating porous enamel. Regarding dentine, EDS teeth had a lower content of C, and a higher content of Ca, P, and O. Ratios for Ca/C and Ca/O were also higher compared with controls. CONCLUSIONS: There are several aberrations of booth enamel and dentine in primary teeth from patients with EDS. These could explain the occurrence of both more dental caries and tooth fractures in patients with EDS.

Social life aspects of young adults with cleft lip and palate: grounded theory approach.

OBJECTIVES: The findings of many questionnaire and inventory studies suggest that people with cleft lip and/or palate report a decreased quality of life. Common problems include dissatisfaction with the external appearance of the lips and nose, speech problems, depression, and anxiety. This qualitative study aimed to explore the subjective perceptions and values of young adults with clefts, particularly with regard to their social lives. MATERIAL AND METHODS: Twelve persons participated in an in-depth interview. Among those, seven had a repaired isolated cleft palate involving only the hard/soft palate. Five had a repaired bilateral cleft lip and palate that had been a continuous lesion of the lip, the alveolar process, and the palate. A grounded theory approach was used to conduct and analyze the interviews. RESULTS: The study revealed seven important categories--hoping to be like other people, being treated differently from others, experiencing deviation from others, regarding oneself as being different from others, lack of recognition, low self-esteem, and receiving recognition from significant others--with hoping to be like other people as the core category. CONCLUSION: Young adults with either cleft lip and palate or isolated cleft palate who received recognition from significant others reported increased self-esteem and greater ability to cope with their social lives.

The approach to dentofacial skeletal deformities using a multisegmentation technique.

This article describes the authors' approach to correcting dentofacial skeletal deformities requiring multisegmentation of the maxilla. Achieving optimal results requires a close collaboration within the orthodontic-surgical team. The importance of attention to detail in the course of the surgical procedure cannot be overemphasized, because complications of avascular necrosis cannot be corrected easily. The multisegmental maxilla is a valuable technique and adds to the versatility of the LeFort I in the treatment of open bite and transverse discrepancies in dentoalveolar deformities.

Maxillary dental arch and occlusion in patients with unilateral cleft lip and palate treated with different delays in closure of the hard palate after early velar repair.

We wanted to find out if growth of the maxilla in 26 patients with unilateral cleft lip and palate (UCLP) was adversely affected by having the residual cleft of the hard palate repaired earlier than had been done previously in a 2-stage palatal closure protocol. The ages at repair of the hard palate of the present patients ranged from 38 to 89 months. Dental casts from ages about 3 years (before any repair of the hard palate), 5, 7, and 10 years of age were analysed. The results indicated that earlier repair of the cleft in the hard palate did not influence maxillary growth differently from the later repair.

Analysis of dental arch relationships in Swedish unilateral cleft lip and palate subjects: 20-year longitudinal consecutive series treated with delayed hard palate closure.

OBJECTIVE: To evaluate the dental arch relationships for a consecutive series from Goteborg, Sweden, who had delayed hard palate closure. DESIGN: Retrospective study. SETTING: Sahlgrenska University Hospital, Goteborg, Sweden. PATIENTS: The dental study models of 104 consecutive unilateral cleft lip and palate subjects. The study cohort was born between 1979 and 1994. Longitudinal records were available at ages 5 (n = 94), 10 (n = 97), 16 (n = 59), and 19 years (n = 46). Five assessors rated models according to the GOSLON Yardstick on two separate occasions each. INTERVENTIONS: These patients had been operated upon according to the Goteborg protocol of delayed hard palate closure (at age 8 years). RESULTS: 85% of subjects were rated in groups 1 and 2 (excellent or very good outcome), 12% were rated in group 3 (satisfactory), and 3% were assigned to group 4 (poor). No patients presented in Group 5 (very poor). Weighted kappa statistics for double determination of Yardstick allocation for five assessors demonstrated values between .65 and .90 for interrater agreement (good/very good) and between .70 and .90 for intrarater agreement (very good). CONCLUSIONS: Delayed hard palate closure as practiced in Goteborg since 1979 has produced the best GOSLON Yardstick ratings in a consecutive series of patients ever recorded worldwide, since the Yardstick was first used in 1983. However, it is noteworthy that a new protocol has been introduced in Goteborg since 1994, in which hard palate closure is done at 3 years due to concerns regarding speech.

Facial talon cusp in primary maxillary lateral incisor: a report of two unusual cases.

Talon cusp is an uncommon dental anomaly in which an accessory cusp-like structure projects from the cingulum area or cemento-enamel junction of the maxillary or mandibular anterior teeth. This anomalous cusp resembles an eagle's talon. It occurs in both the primary and the permanent dentition. A comprehensive literature review shows that only 37?cases of talon cusps have been reported in the primary dentition, of which only 4?cases report this anomaly on the primary maxillary lateral incisor. Though labial/facial talon cusps have been reported in the permanent dentition, no case of a labial talon has been reported in the primary dentition. We report two females with cleft lip and palate with facial talon cusps on the primary lateral incisor and believe that these are the first cases to be reported. Clinical considerations and debate on the etiology of this anomaly are discussed.

Foot pain and disability in individuals with Ehlers-Danlos syndrome (EDS): impact on daily life activities.

PURPOSE: To investigate the amount and severity of podiatric problems in individuals with EDS as well as the consequences on daily life activities, and to compare these results with the results from a comparison group of the general population. METHOD: The Manchester Foot Pain and Disability Schedule (MFPDS) and a demographic and foot-specific form were mailed. RESULTS: One hundred and thirty-six individuals with EDS and 292 from the comparison group responded. The median MFPDS total score in the EDS group was 33 (range 17-49) (mean 32, SD 8) and in the comparison group 17 (range 17-41) (mean 19, SD 4) (P < 0.001). The items most frequently marked with 3 points in the EDS group were: 'I avoid standing for a long time', 'I catch the bus or use the care more often', and 'I get irritable when my feet hurt' (56, 46 and 43%, respectively). When comparing the NRS score (i.e. Numeric Rating Scale) regarding pain intensity between the EDS group (median 5) and the comparison group (median 0), a statistically significant difference was found (P < 0.001). Other foot problems than pain were reported by 73% (n = 100) of the EDS group and by 21% (n = 60) of the comparison group (P < 0.001). The presence of flat feet in the EDS group and the comparison group was reported by 55% (n = 75) and 8% (n = 23) respectively. CONCLUSION: Individuals' with EDS endure difficulties with their mobility due to their foot problems and related disability. It is therefore of utmost importance to find ways to assess the actual foot status for this group and to support the individuals with solutions to their problems with ambulation.

Temporomandibular joint problems and self-registration of mandibular opening capacity among adults with Ehlers-Danlos syndrome. A questionnaire study.

OBJECTIVES: To study maximal mandibular opening capacity and the prevalence of temporomandibular joint (TMJ) problems reported among a larger group of adults with Ehlers-Danlos syndrome (EDS). Furthermore, to compare proportions of disorders with those in a cohort of randomized population- based controls. DESIGN: A questionnaire study with self-registration of maximal mandibular opening capacity. SETTING AND SAMPLE POPULATION: One hundred and fourteen persons with EDS and 114 controls in a randomized population-based cohort. Experimental variables - Self-registered maximal mandibular opening capacity values that were calculated from the markings of maximal interincisal distance on spatulas and the assessments of overbite with the aid of photos. Questions concerning EDS, TMJ problems and other related questions. OUTCOME MEASURE: Mean values of maximal mandibular opening capacity compared between groups. Proportions of affirmative answers about TMJ problems compared between persons with EDS and controls who did not have the syndrome. RESULTS: The EDS persons who reported problems with poor mouth opening capacity when biting into thick pieces of food had a lower mean maximal mandibular opening value compared with the other EDS persons (p < 0.05). The proportions of affirmative answers concerning mobile joints during mouth opening, present TMJ problems, poor mouth opening capacity when biting into thick food, clicking, crepitations and permanent locking were greater compared with the controls (p < 0.05). CONCLUSION: These data corroborate the reports in literature that persons with EDS are naturally predisposed to TMJ problems. The self-registration of maximal mandibular opening capacity was a useful diagnostic tool to provide an objective clinical measure of movement capacity of the TMJ. The clinical measure was in line with the affirmative answers on having problems with poor mouth opening capacity among the EDS persons.

Self-registration of mandibular opening capacity and vertical overbite. A method study.

AIMS: To evaluate a method for self-registration of maximum mandibular opening capacity by means of a spatula and estimation of vertical overbite from photos. METHODS: The study group consisted of 50 adults. Each participant received written instructions, photos, a measuring spatula, and a pencil. The first task was to register maximum interincisal distance. The participant opened up his or her mouth as wide as possible, looked in a mirror, and marked the distance on the spatula. The second task was to estimate the vertical overbite in the intercuspal position. A clinician then estimated the type of overbite and measured the maximum interincisal distance and the vertical overbite with a ruler in millimeters. RESULTS: The normal overbites showed a mean value of 2.4 mm, and a standard value of 2 mm was set. The deep bites showed a mean value of 5.2 mm, and a standard value of 5 mm was set. The standard overbite value, added to the value measured on the spatula, was compared with the clinical values made by the clinician for maximum mandibular opening. The limits of agreement for 95% of the mean difference were -4.2 mm and 4.4 mm. Six people missed the correct diagnosis for the vertical overbite. CONCLUSION: The self-registration method of measuring maximum mandibular opening capacity seems valid for studying major differences in opening capacity when clinical measurements are not possible to perform.