Preventive and interceptive orthodontics for the 5 to 12 year-old. Functional appliances: the Nite-Guide and Occlus-o-Guide techniques.

hree orthodontic procedures are described that are used to prevent, intercept, and correct malocclusions at three distinct stages of dental development. Each stage of development (5 to 7 years, 8 to 12 years, and 12 years through adulthood) uses an appliance selected from a series of several preformed sizes. All have predicted socket dimensions to receive unerupted, erupting or fully erupted teeth. These sockets are prearranged in a perfect Class I occlusion. In the first group of appliances, specifically designed for the 5 to 7 year-old (called Nite-Guide), one selects a single size that is large enough to accommodate the teeth after they become straight. This appliance is worn passively while sleeping and simply guides the incoming incisors to straighten themselves using only their own force of eruption. Once straight, the adult collagenous fibers form and thereby prevent most future relapse from occurring. At the same time, the incoming incisors are prevented from over-erupting into a deep overbite and the mandible is advanced to correct any excess overjet. Similarly-designed appliances are also used to correct malocclusions in the mixed and adult dentitions. To obtain optimum results at these ages, active wear of about two hours per day is required. The treatment time is very fast (1 to 12 months in most cases) and the same appliance is also used as the retainer of choice. Most malocclusion problems such as crowding, rotations, overbite, overjet and TMD are 80 to 95% corrected in those wearing the appliance as directed.

Preventive orthodontics for the 5- to 7-year-old with the Nite-Guide technique.

This preventive orthodontic technique is applicable for the 5- to 7-year-old to prevent problems involving crowding, spacing, rotations, overbite, overjet, gummy smiles, Class II molar relations, and TMJ dysfunction from developing. The technique is based on accepted published research on the development of the dentition. Patients are typically started at 5 or 6 years of age and wear two preformed appliances only while sleeping. The active stage lasts about 2 years. The same appliance is used as a retainer until 12 years when the patient is dismissed About 75% to 80% do not require further orthodontics. The total procedure takes about 2 to 3 hours of total chair time.

Eruption Guidance Appliance effects in the treatment of Class II, Division 1 malocclusions.

The objective of this research was to cephalometrically evaluate the possible effects of the Eruption Guidance Appliance on the craniofacial complex in a sample of 30 patients, over a treatment period of 26 months. The experimental sample consisted of 30 patients (13 females and 17 males), 27 of which presented with a Class II, Division 1 malocclusion and 3 with a Class I malocclusion. The mean initial chronologic age was 9 years; the treatment period lasted 26 months. A control group was used for comparison and consisted of 30 subjects (13 females and 17 males) of similar ages and spanned a similar observation period. Twenty-six subjects of this control group had Class II, Division 1 malocclusions, and 4 had Class I malocclusions. Lateral cephalometric headplates were obtained for the experimental group initially and after 26 months of treatment. The subjects in the control group were randomly selected from a serial growth study sample from the Orthodontic Department at Bauru Dental School, University of São Paulo, for whom cephalometric headplates were obtained annually from 4 to 18 years of age. Comparative statistics were used to assess possible differences between the experimental and control groups during the 26-month period of observation. Results demonstrated statistically significant increases in mandibular growth, degree of mandibular protrusion, lower anterior and total anterior face height, mesial migration of the lower molars, and mandibular posterior dentoalveolar height. There was also lingual tipping and retrusion of the upper incisors, linear protrusion of the lower incisors, improvement in the maxillomandibular relationship and in molar relationship, as well as a significant decrease in the overjet and overbite and an inhibition of the vertical development of the upper incisors. The study demonstrated no significant changes in maxillary growth during the evaluation period. It was concluded from these results that the effects of the Eruption Guidance Appliance during this time period were mostly dentoalveolar, with a smaller, but significant, skeletal effect.

Prevention of overbite and overjet development in the 3 to 8 year old by controlled nighttime guidance of incisal eruption: a study of 43 individuals.

The purpose of this study conducted at Tufts University School of Dental Medicine is to investigate the possibility of limiting the development of an excessive vertical overbite and horizontal overjet during sleeping hours in young children prior to and during the eruption of the permanent incisors. A sample of 43 individuals, whose mean age was 6.17 years, wore a Preventive Eruption Guidance Appliance passively only while sleeping at night for 13 months (mean) to control the development of the overbite as the permanent incisors erupted and to correct the excessive overjet. The mean initial overbite of the sample was 3.4 mm and was reduced to 1.4 mm. The mean initial overjet was 3.0 mm and was reduced to 1.4 mm. Fourteen percent (6 cases) of the sample had an open bite of 1.84 mm (mean), which was reduced to a mean open-bite of 0.81 mm. As a result of the statistical comparison between the treatment sample to the control sample of 50 non-treated individuals, it was shown that the reduction of the overbite and overjet was accomplished solely by altering the problematic dentition without affecting the normal growth pattern or facial morphology as measured from nine lineal dimensions. It was also shown that the change in overbite and overjet was a significant improvement over what would have occurred if no intervention had been instituted, and that the overbite was corrected by restricting continued excessive eruption of the maxillary incisors with only nighttime passive use of the appliance.

A longitudinal study of anterior vertical overbite from eight to twenty years of age.

A statistical evaluation of overbite behavior during growth, finding a mean tendency for increasing overbite from age 8 to 11, then leveling off and gradually decreasing to adulthood, with little net change. Individual behavior varies widely.