Heavy Hitters Flashcards
(23 cards)
Discuss Combination Syndrome
First Described by Kelly (1972) then Saunders (1978).
Kelly described a destructive pattern of residual ridge resorption and soft tissue growth in a group of patients who were wearing complete maxillary dentures opposing distal-extension removable partial dentures (RPDs).
Also called as anterior hyperfunction syndrome,
Classified as Posterior Mandibular ridge resorption Anterior Maxillary Ridge Resorption Down growth of maxillary tuberosities Extrusion of mandibular anterior teeth Papillary hyperplasia
Saunders said : Loss of VDO Occlusal plane discrepancy Anterior repositioning of the mandible poor prosthesis adaption epulis fissuratum periodontal changes
In 2003 Palmqvist Carlsson and Owell challanged it in 2003 refusing to call it a syndrome
Shen and Gogloff looked at 150 patients with maxillary CD and found prevalence 24% of patients with maxillary CD opposing Kennedy Class I RPD
Patients with Mx CD opposing md RPD w with at least 1 Md molar did not show combination syndrome.
What are Predisposing Factors: to combination syndrome
- Quality and use of prostheses – traumatic occlusion, poor adaptation, incomplete extension, patient did not wear mandibular RPD.
- Extraction history – occurs faster if immature sites are present.
- Parafunctional habits
- Angle Class III jaw relationship
- Systemic diseases: diabetes, osteoporosis
Treatment: for combination syndrome
- Educate patient – OH, care of prostheses, leave out of mouth for at least 8 hours daily. **Emphasize importance of recall,** maintenance, awareness of parafunctional habits.
- Tissue conditioning- remove denture minimum of 8 hrs daily, oral massage – until resolution of soft tissue pathosis.
- Diagnostic wax-up – idealized occlusion.
- Occlusion – correct the plane of occlusion discrepancy, create bilateral balance, maxillary anteriors for esthetics and function no or with minimal (provided posteriors are in contact) contacts during centric and eccentric movements.
- Preprosthetic surgery – tuberosity reduction, papillary hyperplasia, epulis fissuratum, segmental osteotomy, posteriorly reposition mandible.
- Impression technique – selective pressure technique, open window in area of redundant tissue (described by Khan et al) and altered cast technique for mandible (Holmes)
- Mandibular RPD – maximum extension to cover retromolar pads and buccal shelf.
- Metal posterior occlusal surfaces – to maintain posterior occlusion.
Discuss Flabby Ridge
When hyperplastic tissue replaces the bone, a flabby ridge develops which is often seen in long-term denture wearers and clearly related to the degree of residual ridge resorption. The reported prevalence for this condition also varies among investigators, but it has been observed in up to 24% of edentulous maxilla, and in 5% of edentulous mandible, and in both jaws
most frequently in the anterior region.
Ainamo 1997 177 edentulous elderly subjects Maxilla > Mandible Mandible = systemic factors Maxilla = local factors
GPT9 for Combination syndrome
combination syndrome : the characteristic features that occur when an edentulous maxillae is opposed by natural mandibular anterior teeth and a mandibular bilateral extension-base removable partial denture, including loss of bone from the anterior portion of the maxillary ridge, hyperplasia of the tuberosities, papillary hyperplasia of the hard palate’s mucosa, supraeruption of the mandibular anterior teeth, and loss of alveolar bone and ridge height beneath the mandibular removable partial denture bases; syn, anterior hyperfunction syndrome
Discuss the calcification of the stylohyoid ligament.
Mineralization of the stylohyoid ligament
- fairly commonly incidental feature on pan.
-Symtoms (pain) glossopharyngeal nerve.
- 4% of the population
Treatment: None if asymptomatic; If symptomatic, steroid therapy, NSAIDs, reassurance or even surgical amputation may be necessary.
Eagle’s syndrome was first described by Dr. Watt Weems Eagle in 1958 as an aggregation of symptoms associated with the elongation of the styloid process or calcification of the stylohyoid ligament. Normal length of the styloid in an adult is approximately 2.5 cm, whereas an elongated styloid is generally >3 cm in length.
Symptoms : Vague pain to swallowing, foreign body sensation in the throat, pain on turning the head or protruding the mandible. Earache, headache, dizziness or transient syncope can also be described by patient. The nerve involved is the glossopharyngeal nerve. Other symptoms may include voice alteration, cough, dizziness, sinusitis or bloodshot eyes.
Although approximately 4% of the population is thought to have an elongated styloid process, only a small percentage (between 4% and 10.3%) of this group is thought to actually be symptomatic.
Differential diagnosis: None
Discuss the Styloid apparatus:
Bone:
Styloid Process- 2nd Branchial arch- supplied by Facial nerve
Muscles:
Stylohyoid muscle- 2nd Branchial arch- supplied by Facial nerve
Stylopharyngeus muscle- 3rd Branchial arch- supplied by Glossopharyngeal nerve
Styloglossus muscle- Occipital myotomes- Hypoglossal nerve
Ligaments:
Stylohyoid ligament- 2nd Branchial arch- supplied by Facial nerve
Stylomandibular ligament- Deep part of the cervical fascia- Auriculotemporal nerve
why are people refusing to call combination syndrome a syndrome ?
In 2003 Palmqvist Carlsson and Owell challanged it in 2003 refusing to call it a syndrome
because
What is some data for combination syndrome?
Kelly- 1972
6 patients followed up for 3 yrs all showed a reduction of the anterior bone in the maxilla along with enlarged tuber- osities.
-5 patients there was an increased bone level of the tuberosities.
- Kelly blamed the mandibular RPD and the lack of a posterior seal in the maxillary denture for these changes.
Shen and Gogloff
150 PATIENTS
- PRESENCE OR ABSENCE OF SYMPTOMS BY KELLY/SAUNDERS
- Tissue changes found in maxillary CD and mandibular distal ext RPD
-Preserve lower teeth to provide distal abutment better option
- Preventing the degenerative changes that complete maxillary dentures opposing the Class I partial dentures bring about may only be possible through treatment planning!!! to avoid this combination of prostheses
What did kelly say was treatment/prevention for Combination syndrome
Advocated for endosseous dental implants is one method to retain posterior support.
Provide a CD occlusion.
Did not advocate for extraction of lower anterior teeth but rather retain weak posterior teeth as abutments by means of endo and perio.
cover retromolar pad to prevent or reduce resorption and cover buccal shelf
Could it be from the negative eprssuree/suction effect of the posterior palatal seal area
Carlsson1 observed one patient who had an increase in the maxillary ridge height in the molar region after wearing dentures for two years. He postulated: “It may have been due to the development of a fibrous part possibly1 owing to the suction effect when the denture moved.”
Why fixed for combination syndrome?
Wictorin5 states that to prevent bony resorption, mechanical forces must be distributed over as large an area of the basal seat as possible, and the denture must make as little movement as possible against its basal seat, and that these factors are strongly interconnected. With the lower anterior teeth causing trauma and bone loss from the anterior part of the max- illae, and with the denture base moving more and more on its foundation, a very destructive situation exists.
You have a Cantilever without a bar, what is the literature to support this?
the length of the can cantilevered segments had an influence on the resistance to fracture of the cantilevered segments and in mechanical complications
When comparing to metal acrylic resin or metal ceramic where a bar is required, the complication rate is fewer.
- Metal acrylic (Tooth debonding ) (Priest)
Disadvantages - lack of natural color in gingival areas
- Tooth debonding (Purcell, Bozini, Ortorp, Bergendal)
[Metal ceramic] (porcelain chipping)
Disadvantages of chipping
- ceramic chipping, expensive, laborious to fabricate, difficult to repair/technique sensitive, wear of occlusal surfaces,
Rojas
- 20 Double arch Monolithic Zr prostheses 3-7yr f/u
- Zirconia prostheses fixed (chipping 7yr in one and screw loosening 3yr in 1 out of 20)
- No chipping of Zr was noted
Zirconia is very hard and abrasive if rough, wouldnt resin vs resin reduce the need for tooth replacement due to tooth wear?
Patients must present for 6month recalls to evaluate the incidence of wear. Wear is inevitable, however, if wear occurs, with zirconia you can just replace 1 arch instead of both.
(Purcell) looked at wear rates of metal resin implant-supported fixed complete dentures versus maxillary complete dentures
- after 5 years 48% of complete dentures needed replacement teeth and 19.6% of implant-supported metal resin prostheses needed wear.
- 30% of dentures needed to be re-made
Gupta
The use of Ceramic teeth in implant-supported complete
dentures could overcome problems associated
wi the plastic teeth.
Zirconia can offer the option for a patient who wants to go fixed in the maxilla in the future with less complications such as porcelain fracture, denture tooth debonding as reported by Priest, purcell.
Zirconia has less incidence of chipping (Rojas, Bidra,
Lets say you were to go metal resin, how do you prevent debonding?
o decrease the amount of tooth fracture, several steps might be considered. Regular occlusal analyses should be performed to ensure distribution of the load and elimination of interferences. The anterior teeth on the metal-resin implant-fixed complete dental prostheses should be well supported by the framework and acrylic resin. It is more difficult for maxillary anterior teeth to have increased support, therefore retentive diatorics and/or treatment with dichloromethane should be considered to increase retention of anterior teeth.
Wont you cause combination syndrome with an implant-supported fixed against an upper denture?
Lechner reported “Combination Syndrome” -like signs have been reported,42–44 but very few studies have been performed to analyze the consequences suffered in the maxilla restored with a complete denture when opposed by a metal-resin implant-fixed complete dental prostheses.
(Gupta et al) implant-supported fixed prosthesis
occluding with a maxillary complete denture did
not appear to promote a condition similar to
Combination Syndrome.
-11 subjects mx cd md is-fixed
- Loss of posterior support due to wear (RECALLS!!!)
- found that the average loss of alveolar ridge height in the anterior maxilla was 0.17 mm when there was a maxillary conventional removable denture and a mandibular metal-resin implant-fixed complete dental prosthesis, which was not statistically significant compared to patients with a maxillary and mandibular complete removable denture.
(Lechner Gupta)
Gupta S, Lechner S, Duckmanton N. Maxillary changes under complete dentures opposing mandibular implant-supported fixed prostheses. J Prosthet Dent 1999;12:492–497.
43. Lechner S, Mammen A. Combination syndrome in relation to osseointegrated implant-supported overdentures: A survey. Int J Prosthodont 1996;9:58–64.
Occlusal forces of lower implants will Break the upper denture, why are you doing this treatment?
Stafford et al found that loading
forces did not increase.
. However, Falk et al,20 measuring closing and chewing forces in 10 sub jects, found them to be comparable to those of partially restorednatural dentitions, with greater forces in the posterior region of the maxillary denture opposing the cantilevered is prosthesis.
Thus, decreased the cantilever size and frequent recalls
Gupta found that The stability
of the denture was also fo und to be adequate
in (82%) of the patients.
Why not cantilever more?
Falk et al,20 measuring closing and chewing forces in 10 sub jects, found them to be comparable to those of partially restorednatural dentitions, with greater forces in the posterior region of the maxillary denture opposing the cantilevered is prosthesis.
Thus, decreased the cantilever size and frequent recalls
Youre going to cause combination syndrome even more why not do an overdenture and have bilateral balanced occlusion?
(Jacobs, Lechner, Barber)
-Loss of posterior occlusion leading to bone loss in the anterior ridges opposing implant-supported overdentures.
(Jacobs, Lechner, Barber) the amount of bone loss noted in the anterior maxilla was equivocal, and a linear relationship could not be established for annual vertical bone loss with respect to the age and sex of the subjects or duration of wear of the prosthesis.
describe maxillary anatomy
Anterior Maxilla Labial frenum, incisivus labii superiorioris muscle, Levator anguli oris muscle, Risorius muscle, Orbicularis oris muscle spans the entire anterior area between
Lateral buccal frena, buccal frenum, buccinator, temporalis tendon and muscle/ Coronoid process
Posterior
pterygomaxillary notch, and pterygomandibular raphe.
Palatine aponeurosis (Tensor veli palatini, levator veli palatini, palatopharyngeous, palatoglossus, and musculus uvulae muscles).
describe mandibular anatomy
Anterior
Labial frenum, mentalis, incisivus labii inferioris, depressor labii inferioris, depressor anguli oris, orbicularis oris
Lateral
buccal frenum, buccinator, masseter muscle, temporalis muscle,
Posterior superior constrictor pterygomandibular raphe palatoglossus muscle retromolar pad
Lingual
Mylohyoid muscle
Genioglossus muscle
Lingual frenum.
5 factors of neutrocentric occlusion, did I apply any of them to your case
5 factors of neutrocentric occlusion, did I apply any of them to my case
Discuss Neutrocentric Occlusion
First described by DeVan in 1954.
Neutrocentric concept
o Neautralization of the inclines
o Centralization of occlusal forces acting on the denture foundation
Goal: To preserve underlying bony structurees by distributing the forces using a particular tooth arrangement.
Five elements
- Position (most important) - posterior teeth should be placed over the residual ridge as far lingually as the tongue would allow, so that forces will be perpendicular to the support areas
- Proportion - reduce tooth width by 40% to reduce vertical stress on the ridge by narrowing the occlusal table.
- Pitch (inclination and tilt): There is no compensating curve or incisal guidance. The occlusal plane is simply placed parallel to the underlying and midway between them. This will direct the force perpendicular to the bone.
- Form: Flat teeth are used to reduce lateral forces
- Number: Only 6 posterior teeth
- Especially good for Class II, III and reverse articulations
- Least esthetic of all occlusal schemes and no balanced occlusion
- Teeth position could interfere with the tongue, lip and cheek function
Hanau quint or thielman;s formula
Hanau quint :
- Condylar Inclination
- Incisal Guidance
- Cusp Height
- Compensating Curve
- Plane of Occlusion
Thielman’s formula should equal 1 so Rules for balanced occlusion are that Theilmann’s formula should equal 1.
(CG x IG)/(CHxCCxOP)=1
Fixed factors are condylar guidance and occlusal plane because it is primarily controlled by nature and esthetics.
If you increase incisal guidance you can increase compensating curve and cusp height.
