L'Tanya J. Bailey

Long-term stability of surgical open-bite correction by Le Fort I osteotomy.

Skeletal changes greater than those observed in untreated adults have been noted beyond 1 year post-surgery in adult patients who had surgical correction of a long face deformity. The stability of skeletal landmarks and dental relationships from 1 to >3 years post-surgery was examined in 28 patients who had undergone surgery of the maxilla only, and in 26 patients who had undergone 2-jaw surgery to correct >2 mm anterior open bite. Although the average changes in almost all landmark positions and skeletal dimensions were less than 1 mm, point B moved down >2 mm and face height increased >2 mm in one-third of the maxilla-only group and in 40% of the 2-jaw group (>4 mm in 10% and 22% respectively). Overbite decreased 2-4 mm in only 7% of the maxilla-only and 12% of the 2 groups, with no changes >4 mm, because in three-fourths of the patients with an increase in anterior face height, further eruption of the incisors maintained the overbite relationship. In the maxilla-only group, mandibular length (Co-Pg) showed >2 mm long-term change in 45% of the patients, two-thirds of whom showed an increase rather than a decrease in length. In the 2-jaw group, no patients showed a decrease in Co-Pg length and one-third had an increase. For both groups, changes in overjet were smaller and less frequent than changes in mandibular length.

Stability of the palatal rugae as landmarks for analysis of dental casts in extraction and nonextraction cases

To determine whether the positions of the palatal rugae were affected by orthodontic therapy, pre- and posttreatment maxillary dental casts of 57 adult patients treated in the graduate orthodontic clinic at the University of North Carolina were evaluated. The orthodontic extraction group (n = 27) was composed of patients whose treatment included the extraction of two maxillary premolars. The remaining patients (n = 30) had been treated without extractions. Transverse changes observed over time were significantly different from zero only for the medial points of the first rugae in the nonextraction group and for the lateral points of the first rugae in the extraction group. None of the changes observed in the transverse measures were statistically different between the two groups. In the extraction group, there were significant anteroposterior changes in the right lateral points between the first and second rugae and between the second and third rugae, and in the right medial points between the second and third rugae. There were no statistically significant anteroposterior changes observed in the nonextraction group over time. When the two groups were compared, the average distance between the lateral first and second right rugae, and the average distance between the lateral second and third right rugae were significantly different. The medial and lateral points of the third rugae appear to be stable landmarks for the construction of anatomic reference pints in longitudinal cast analysis.

Assessment of patients for orthognathicsurgery

Rapid advances in orthognathic surgery now allow the clinician to treat severe dentofacial deformities that were once only manageable by orthodontic camouflage. These cases were often compromised with unacceptable facial esthetics and unstable occlusal results. Over the past 25 years, there have been numerous improvements in technology and the surgical management of dentofacial deformities. These progressions now allow more predictable surgical outcomes, which ensure patient satisfaction. Not all patients are candidates for surgical treatment; therefore, patient assessment and selection remains paramount in the process of diagnosing and treatment planning for this type of irreversible treatment. The inclusion of patients in the decision-making process increases their awareness and acceptance of the final result. The past three decades indicate an increased usage of orthodontic treatment by both children and adults. Patient demographic profiles for severe occlusal and facial characteristics are presented in an effort to understand the epidemiological factors of malocclusion and predict the populations need for this service.

Long-term soft tissue changes after orthodontic and surgical corrections of skeletal class III malocclusions.

OBJECTIVE To evaluate long-term soft tissue changes after orthodontic and surgical corrections of skeletal Class III malocclusions. MATERIALS AND METHODS Postoperative cephalometric radiographs at 1 year and at 5 years or more after treatment were digitized for 92 patients who had surgical correction of their Class III problem by LeFort I maxillary advancement (n = 48), mandibular setback (n = 12), or a combination of the two procedures (n = 32) and for 25 patients who received orthodontic treatment only. RESULTS For all groups, the mean changes were quite small. For most measurements, fewer than 20% of patients experienced long-term changes from 2 mm to 4 mm, and fewer than 10% experienced long-term changes greater than 4 mm. CONCLUSIONS A smaller percentage of surgically treated Class III patients showed long-term soft tissue changes than did surgically treated Class II patients, but compared with both Class II patients and untreated adults they experienced greater long-term forward projection of the soft tissue chin.

Long-term outcome of surgical Class III correction as a function of age at surgery

INTRODUCTION In this study, we assessed whether the likelihood of a positive overjet 5 to 10 years after Class III surgery was affected by age at the surgery or the type of surgery and evaluated the amount and pattern of postsurgical growth. METHODS Cephalometric measurements including overjet were evaluated from immediately postsurgery and long-term recall cephalograms of 104 patients who had had surgical Class III correction and at least 5-year recalls. The patients were classified as younger (<age 18 years for females at the surgery or 20 years for males) or older and by type of surgery (maxilla only vs mandibular only or 2 jaw). For the younger patients, the timing of treatment was based largely on serial cephalometric radiographs that eventually showed minimal or no mandibular growth. RESULTS Long-term changes in overjet and other cephalometric characteristics in the younger and the older patients were similar. No patients in the sample had negative overjet in the long term, but zero overjet (<1 mm) was observed in some patients in all groups. Patients who had mandibular setback at any age were 2.6 times more likely to have zero overjet in the long term (P = .003) than those with maxillary surgery alone. For the younger patients, the likelihood of zero overjet in the long term was not significantly different from patients who were treated later (P = .87), with or without mandibular surgery. CONCLUSIONS The data support the use of serial cephalometric radiographs, with surgery deferred until little or no mandibular growth is observed, to determine the timing of Class III surgery in younger patients.

Level of agreement in Clinicians' perceptions of class II malocclusions

To evaluate the extent to which surgeons and orthodontists agree on the nature and severity of dentofacial problems requiring orthognathic surgery, three clinicians active in a specialized clinic for treatment of dentofacial deformities scored the pretreatment records of 37 adult class II patients. Each clinician first indicated whether a skeletal/dental problem existed in the maxilla and mandible and then rated the severity of the problem on a visual analog scale. The level of agreement among the three clinicians was highest for dental problems and lowest for skeletal anteroposterior measures. There was a significant difference among the clinicians in the percentage of patients identified as having a retrusive midface and excessive facial thirds. The agreement on the severity of the problem was generally low even for those patients for whom the clinicians agreed on the type of problem. The data suggest that personal experience and clinical background play a major role in diagnosis and treatment planning. Joint treatment planning conferences between the surgeon and orthodontist offer an opportunity for different plans to be discussed, with the preferred treatment option selected for an individual patient.