RPE

As we see more adults entering comprehensive orthodontic treatment, we must be more attuned to the implications of periodontal issues. In this updated chapter, Robert Vanarsdall, Ignacio Blasi and Antonino Secchi review periodontal issues that impact orthodontic tooth movement. They describe periodontal "high risk" factors, mucogingival considerations, and problems with ectopic as well as ankylosed teeth. A new section on alveolar decortication and augmentation grafting has been added to address the increased use of these procedures designed to develop the alveolar housing and potentially increase the speed of tooth movement. Excellent clinical examples are pictured throughout the chapter.

Rapid palatal expansion (RPE) has been used primarily to treat dental crossbites or for space gaining to prevent extractions with little or no attempt made to coordinate or normalize the transverse skeletal pattern. Traditionally, maxillary orthopedics has been performed using the dental units only as anchorage (e.g., Hyrax or Haas appliances). Dental anchorage not only has created limited skeletal orthopedic change, but also can cause significant adverse periodontal outcomes and unstable side effects. There is a clear correlation between buccal tooth movement and gingival recession and bone dehiscences. These adverse periodontal responses with RPE indicate the importance of early treatment. The beneficial periodontal effects of transverse skeletal correction have been a primary focus of our research for the past 35 to 40 years. We have emphasized the importance of correcting transverse skeletal discrepancy to: 1) prevent periodontal problems; 2) achieve greater dental and skeletal stability; 3) improve dentofacial esthetics by eliminating or improving buccal corridors; and 4) improve airway resistance. When it may be critical to save the natural dentition, we do not want to introduce adverse dental/skeletal changes for adolescent patients and/or patients with advanced periodontal disease. New advances in skeletal anchorage should permit orthopedic change without adverse dental changes by applying force directly to the maxillary bone; an innovative technique to maximize the skeletal maxillary changes in the transverse dimension is explained in this chapter. Furthermore, diagnosis of the transverse dimension—the use of cone-beam computed tomography (CBCT) for 3D evaluation of skeletal changes, the benefits of the skeletal transverse changes of the whole maxillofacial complex and its periodontal response, the changes in airway and non surgical RPE with bone-anchored appliances utilizing temporary anchorage devices (TADs)—is described and discussed.

Ratings of perceived exertion (RPE: 0–10) during resistance training with varying programming demands were examined.
Blood lactate (BLa) and muscle activation (using surface electromyography: EMG) were measured as potential mediators
of RPE responses. Participants performed three sets of single arm (preferred side) bicep curls at 70% of 1 repetition
maximum over 4 trials: Trial (A) 3 sets × 8 repetitions × 120 s recovery between sets; (B) 3 sets × 8 repetitions × 240 s
recovery; (C) 3 sets × maximum number of repetitions (MNR) × 120 s recovery; (D) 3 sets ×MNR× 240 s recovery.
Overall body (RPE-O) and active muscle (RPE-AM) perceptual responses were assessed following each set in each trial.
Biceps brachii and brachioradialis muscle EMG was measured during each set for each trial. RPE-O and RPE-AM were
not different between Trial A (3.5 ± 1 and 6 ± 1, respectively) and Trial B (3.5 ± 1 and 5.5 ± 1, respectively) (p < .05).
However, RPE-AM was significantly greater in Trial C (7.5 ± 1.5) and Trial D (7.5 ± 1.5) than in Trial B (p < .05). There
were no significant differences in muscle activation or BLa between trials; however, work rate (tonnage/min) was greater
in Trials C and D compared to Trial B. In conclusion, BLa and muscle activation were not related to RPE, but resistance
training variables, such as work rate, may impact on RPE when intensity (%1RM) and the number of sets completed
remain constant.

Introduction: The effect of the maxillary expander on the inferior third of the face may be conditioned by the type of expander when done with an occlusally bonded acrilic covering or on conventional bands.
Objective: The purpose of this retrospective study was to compare the effects of expander design on the vertical plane using a) a banded Haas expander and, b) a Haas expander with acrilic covering, in the Steiner mandibular plane.
Materials and Methods: Initial (before treatment) and final (months after expander removal) lateral cephalometric x-rays of 20 patients with disjunction were retrospectively compared: ten patients with Haas expanders bonded with acrilic covering and ten patients with banded Haas expanders. The reference plane employed was S-Na. The mandibular plane was Go-Gn anatomic.
Results: Significant differences existed between both groups before initiating treatment. It was observed in the group with banded Haas expanders that the mandibular plane of 5 subjects remained unchanged while increasing in the other 5 subjects. The mean initial mandibular plane was 34.7º, while the final mean was 35.55º. No significant differences existed.
With respect to the group with Haas expanders with acrilic covering, the mandibular plane did not change in four subjects, while decreasing 5 others and increasing by 4º in one individual. Average initial mandibular plane was 39.25º; The final average was 38.85º. There were, similarly no significant differences present in this group.
Conclusions: Rapid Palatal Expansions (RPE) conducted with banded Haas expanders remains unchanged or increase lightly the mandibular plane. On the contrary, those conducted with acrilic covered expanders tend to either maintain or decrease the mandibular plane angle. The acrilic covered expander appears to provide some control over vertical dimension, thus indicating its more appropriate use in patients with increased vertical dimension such as dolichofacial patterns. Conclusions from this study are based on results obtained from a retrospective study in which samples were not randomly chosen. We think that further prospective research studies on the effect of maxilliary expansion on facial pattern should be done.