American Journal of ORTHODONTICS and DENTOFACIAL ORTHOPEDICS m=
Founded in 1915--Seventy-five years of continuous publication
ii
i
Volume 97 Number 5
i
i
i
May 1990
Copyright © 1990 by Mosby-Year Book, Inc.
CASE REPORT
Class I malocclusion with severe open bite skeletal pattern treatment Roberto Martina, MD, DDS,* Alberto Laino, MD, DDS,** and Ambra Michelotti, DDS*** Naples, Italy A case report of a Class I malocclusion with a severe skeletal open bite, excessive overjet, a high mandibular plane angle, and a forward maxillary rotation is presented. Treatment has eliminated the causative factors (i.e., mouth breathing, enamel hypoplasia of the first molars, and abnormal tongue posture and function). A normal growth pattern has been restored, ensuring a good and stable orthodontic result. (AM J ORTHOD DENTOFACORTHOP1990;97:363-73.)
A
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suggested by Proffit, * "The majority of the American and Western European populations have malocclusion o f some type, but only a small percentage can be attributed to a known specific cause." Therefore the type of treatment offered to the greatest majority of patients is more often a symptomatic therapy rather than one directed at eliminating the causative factors. Yet when the causative factors can be identified by a careful examination and complete diagnosis, greater possibilities for optimal therapy exist with less complicated treatment.
CASE REPORT In the following case (Fig. 1), three factors appear to have significantly affected the growth pattern. 1. A mouth breathing habit 2. Hypersensitivity during occlusal contacts caused by enamel hypoplasia of the first permanent molars 3. Abnormal tongue posture and function This combination of factors resulted in a severe open bite caused by a forward rotation of the maxilla and a backward
From the Departmentof Orthodontics,II Schoolof Medicineand Dentistry, Naples. *Professorand Chairman. **AssistantProfessor. ***ResearchFellow. 8/4/10426
rotation of the mandible (Fig. 2). This morphofunctional abnormality appears to coincide with that described by many authors ~'4 who have observed, experimentally or clinically, a correlation between an oral breathing habit and open mouth posture with significant facial growth pattern changes. Harvold's primate experiments'- showed that a total nasal obstruction may or may not cause a change in mandibular shape and growth direction, depending on how the animal obtained air. Some animals obtained air by rotating the mandible inferiorly and chronically maintaining it in this position; all of these animals developed malocelusions and a long-face syndrome. Other airway-obstructed animals kept their mouths closed, only lowering the mandible rhythmically for each breath. At other times they maintained normal occlusion. The conclusion is that changed facial morphology and mandibular growth direction resulted only when the mandible was held in a chronically lowered position. The patient in the current report was obliged to maintain a chronic downward and backward rotation of the mandible because of the nasal obstruction and hypersensitivity during occlusal contacts. Treatment eliminated the causative factors and restored a normal growth pattern. A good and stable result was attained.
DIAGNOSIS The patient, a boy aged 12 years 4 months at the start of treatment, had a severe skeletal open bite and an enamel hypoplasia of the first permanent molars and incisor teeth. The facial soft tissue reflected the typical face of a mouth-
363
364
Martina, Laino, and Miche[otti
Am. J, Or/hod. Den/ofat. Or/hop. May 1990
Fig. 1. Pretreatment facia,I and intraoral views. The patient was 12 years 4 months of age with a Class I malocclusion with an open bite skeletal pattern, Note the hypoplasia of first molars and incisor teeth.
Fig. 1 (Cont'd). Pretreatment intraoral views.
Volume 97 Number 5
Case report
BO° -
FaCial
85%
Facial
32°= Mand.
Axis
Plane Plane
61*=
Lower
Fac.
26 ° "
Rand,
Arc
÷ 0
365
Hei!
6m C o n v s x . McNamara P l a n e
7 °= ANS-PN5 / Fh 49% Na-Cf-PtA + 2z T : APo 21 ° " T " APo 13 - 6 : PTV + I,
E Line
Fig. 2. Pretreatment cephalometric radiograph and tracing at age 12 years 4 months. A severe hyperdJvergent growth pattern is present
breathing patient (i.e., long-face syndrome) (Fig. 1). The restricted nasal airflow was the result of rhinitis caused by inhalant allergens, as confirmed by the otolaryngologist. The patient had an Angle Class I dental malocclusion with a severe skeletal open bite that caused a tongue thrust habit during deglutition. The hypersensitivity during occlusal contacts caused by the enamel hypoplasia of first molars prevented the patient from biting on teeth and increased the severity of the open bite. Oral hygiene was poor and a considerable accumulation of bacterial-discolored plaque was evident. No dental resto-
rations were present. Temporomandibular joint function appeared clinically normal and the associated musculature was not tender to palpation. Also clinically observable were strain of the eircumoral musculature because of incompetent lips, chin crinkling as a result of mentalis muscle strain on closure, and narrow upwardly tumed na'es. Chapped lips and inflamed oral hypertrophic gingiva resulting from mouth breathing also were noted. The face was symmetric with a convex profile. Upper incisors were inclined labially and upper deciduous
366
Martina, Laino, and Michelotti
Am. J. Orthod. Dentofac. Orthop. May 1990
Fig. 3. Study models of original malocclusion demonstrating severe open bite and increased overjet.
Fig. 4. Posttreatment study models at age 15 years 4 months. Note bite closure and improvement in dental arch form and alignment,
Volume 97 Number 5
Case report
Fig. 5. Posttreatment facial views after 36 months of active treatment,
Fig. 5 (Cont'd). Posttreatment intraoral views after 36 months of active treatment,
367
Fig. 5 (Cont'd). Posttreatment intraoral views after 36 months of active treatment.
Fig. 6. Panoramic radiographs. A, Pretreatment at age 12 years 4 months. B, Posttreatment radiograph at age 15 years 4 months.
Volume 97
Case report
369
Number 5
t lt
86°= Facial Axis 89*= Facial
,,','
Plane
,,~ ',
26°= Hand. Plane 53"= Lower Fac. Height
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+ 2= C o n v e x
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Founded in 1915--Seventy-five years of continuous publication
ii
i
Volume 97 Number 5
i
i
i
May 1990
Copyright © 1990 by Mosby-Year Book, Inc.
CASE REPORT
Class I malocclusion with severe open bite skeletal pattern treatment Roberto Martina, MD, DDS,* Alberto Laino, MD, DDS,** and Ambra Michelotti, DDS*** Naples, Italy A case report of a Class I malocclusion with a severe skeletal open bite, excessive overjet, a high mandibular plane angle, and a forward maxillary rotation is presented. Treatment has eliminated the causative factors (i.e., mouth breathing, enamel hypoplasia of the first molars, and abnormal tongue posture and function). A normal growth pattern has been restored, ensuring a good and stable orthodontic result. (AM J ORTHOD DENTOFACORTHOP1990;97:363-73.)
A
S
suggested by Proffit, * "The majority of the American and Western European populations have malocclusion o f some type, but only a small percentage can be attributed to a known specific cause." Therefore the type of treatment offered to the greatest majority of patients is more often a symptomatic therapy rather than one directed at eliminating the causative factors. Yet when the causative factors can be identified by a careful examination and complete diagnosis, greater possibilities for optimal therapy exist with less complicated treatment.
CASE REPORT In the following case (Fig. 1), three factors appear to have significantly affected the growth pattern. 1. A mouth breathing habit 2. Hypersensitivity during occlusal contacts caused by enamel hypoplasia of the first permanent molars 3. Abnormal tongue posture and function This combination of factors resulted in a severe open bite caused by a forward rotation of the maxilla and a backward
From the Departmentof Orthodontics,II Schoolof Medicineand Dentistry, Naples. *Professorand Chairman. **AssistantProfessor. ***ResearchFellow. 8/4/10426
rotation of the mandible (Fig. 2). This morphofunctional abnormality appears to coincide with that described by many authors ~'4 who have observed, experimentally or clinically, a correlation between an oral breathing habit and open mouth posture with significant facial growth pattern changes. Harvold's primate experiments'- showed that a total nasal obstruction may or may not cause a change in mandibular shape and growth direction, depending on how the animal obtained air. Some animals obtained air by rotating the mandible inferiorly and chronically maintaining it in this position; all of these animals developed malocelusions and a long-face syndrome. Other airway-obstructed animals kept their mouths closed, only lowering the mandible rhythmically for each breath. At other times they maintained normal occlusion. The conclusion is that changed facial morphology and mandibular growth direction resulted only when the mandible was held in a chronically lowered position. The patient in the current report was obliged to maintain a chronic downward and backward rotation of the mandible because of the nasal obstruction and hypersensitivity during occlusal contacts. Treatment eliminated the causative factors and restored a normal growth pattern. A good and stable result was attained.
DIAGNOSIS The patient, a boy aged 12 years 4 months at the start of treatment, had a severe skeletal open bite and an enamel hypoplasia of the first permanent molars and incisor teeth. The facial soft tissue reflected the typical face of a mouth-
363
364
Martina, Laino, and Miche[otti
Am. J, Or/hod. Den/ofat. Or/hop. May 1990
Fig. 1. Pretreatment facia,I and intraoral views. The patient was 12 years 4 months of age with a Class I malocclusion with an open bite skeletal pattern, Note the hypoplasia of first molars and incisor teeth.
Fig. 1 (Cont'd). Pretreatment intraoral views.
Volume 97 Number 5
Case report
BO° -
FaCial
85%
Facial
32°= Mand.
Axis
Plane Plane
61*=
Lower
Fac.
26 ° "
Rand,
Arc
÷ 0
365
Hei!
6m C o n v s x . McNamara P l a n e
7 °= ANS-PN5 / Fh 49% Na-Cf-PtA + 2z T : APo 21 ° " T " APo 13 - 6 : PTV + I,
E Line
Fig. 2. Pretreatment cephalometric radiograph and tracing at age 12 years 4 months. A severe hyperdJvergent growth pattern is present
breathing patient (i.e., long-face syndrome) (Fig. 1). The restricted nasal airflow was the result of rhinitis caused by inhalant allergens, as confirmed by the otolaryngologist. The patient had an Angle Class I dental malocclusion with a severe skeletal open bite that caused a tongue thrust habit during deglutition. The hypersensitivity during occlusal contacts caused by the enamel hypoplasia of first molars prevented the patient from biting on teeth and increased the severity of the open bite. Oral hygiene was poor and a considerable accumulation of bacterial-discolored plaque was evident. No dental resto-
rations were present. Temporomandibular joint function appeared clinically normal and the associated musculature was not tender to palpation. Also clinically observable were strain of the eircumoral musculature because of incompetent lips, chin crinkling as a result of mentalis muscle strain on closure, and narrow upwardly tumed na'es. Chapped lips and inflamed oral hypertrophic gingiva resulting from mouth breathing also were noted. The face was symmetric with a convex profile. Upper incisors were inclined labially and upper deciduous
366
Martina, Laino, and Michelotti
Am. J. Orthod. Dentofac. Orthop. May 1990
Fig. 3. Study models of original malocclusion demonstrating severe open bite and increased overjet.
Fig. 4. Posttreatment study models at age 15 years 4 months. Note bite closure and improvement in dental arch form and alignment,
Volume 97 Number 5
Case report
Fig. 5. Posttreatment facial views after 36 months of active treatment,
Fig. 5 (Cont'd). Posttreatment intraoral views after 36 months of active treatment,
367
Fig. 5 (Cont'd). Posttreatment intraoral views after 36 months of active treatment.
Fig. 6. Panoramic radiographs. A, Pretreatment at age 12 years 4 months. B, Posttreatment radiograph at age 15 years 4 months.
Volume 97
Case report
369
Number 5
t lt
86°= Facial Axis 89*= Facial
,,','
Plane
,,~ ',
26°= Hand. Plane 53"= Lower Fac. Height
-.'J ....
360= Hand, Arc
,.) , - e ,, "~
+ 2= C o n v e x
I= McHamara Plane
+
/ /
t t n~/.,~,i ["
