CATEGORY 74 AUSTRALASIAN DENTIST CLINICAL guidance on the working side lateral occlusion. Lateral guidance using molar rise was bio-designed with gold or zirconia crowns on the first or second molars (Figs. 3 and 4). This involved a lower molar buccal cusp guiding along an upper lateral guidance/restrictive ridge located on an upper buccal cusp to create a protective vertico-lateral mandibular vector (Figs. 3 and 4). The length of the restrictive path was 2.5 to 3.5 mm depending on the buccopalatal width of the upper molar, the lingual tilt on the guiding lower buccal cusp and the presence of an extreme mandibular excursion (Fig.4). Protrusive guidance was achieved with protrusive ramps (Darveniza 2001) on the upper molars starting in the central pit of the distal fossa towards the oblique ridge region or within the central pit of the mesial fossa towards the mesial marginal ridge (Fig. 3). Lower buccal cusps guided along these ramps bilaterally, with a sagittal vector, resulting in a protective protrusive path in early to mid-path and mid-path to final path was guided by ramps (Darveniza 2001) located ideally on the palatal surfaces of the central incisors ending at edge to edge (Fig. 7). However, if a very large anterior overjet was present protective tooth guiding contacts can only be afforded by the molars in early path and the incisors in final path but with no guiding contacts in mid path. Recording From the 200 TMD cases only three dolichofacial patients were present and these case studies have been illustrated (Table 1). The following details have been recorded: age, gender, relevant TMD clinical notes, patient reported percentage improvements following occlusal splint therapy, occlusal equilibration and molar guidance, and years of follow-up and if still wearing a splint (Table 1). Following this therapy each patient was asked what level of improvement, in percentage terms, had been achieved from the initial examination. Some patients replied giving a single percentage figure which was recorded, and the others gave a range and for these patients the mean was recorded (Table 1). The years of follow up since fitting the splint (with a minimum of three years) and those patients still wearing a splint were recorded (Table 1). A splint wearer was deemed as a patient who wore a splint on average of six nights or more a week over the follow up period. Missed nights were accepted if a patient had a respiratory condition (flu, sinus infection or other affliction) that obstructed their airway or another debilitating condition that interfered with splint wearing. Case studies Patient number six Patient number six started treatment in 1991 and was the first patient the author treated with molar guidance (Figs. 5, 6 and 7) (Table 1). The occlusal scheme in hinge occlusion was full contacts on the second molars but the first molars only had a contact in the distal fossae/marginal ridges. An open bite extended from the mesial section of the first molar, all premolars, and anterior teeth. Lateral occlusion was molar guided with unprotected disto-horizontal lateral vectors and protrusive occlusion was unilaterally non-sagittal guided by the right molars and then unilaterally with 41 on the 11 teeth. This patient had severe mouth restriction (23 mm) and the MRI revealed non-reducing antero-medial dislocated discs. In hinge occlusion the 37 and 47 prematurely contacted on the distal marginal ridges of 17 and 27 and the mandible retruded 2-3 mm posteriorly. This extreme and rare posterior slide resulted in severe obdurate TMJ pain and otalgia. This intractable pain was probably caused by the posterior slide allowing the condyles to push directly onto the innervated bilaminar zone of the posterior ligament of the disc and backwards into the ear. Formal fully protective occlusal splint therapy was performed with only 10% improvement in Fig. 3 An occlusal view of bio-designed molar guidance on 17 and 27 crowns for a dolichofacial patient, in 1995. This laboratory view shows the buccal cusps were inadvertently overbuilt in a buccal direction by 1.5-2.0 mm and required significant modification prior to fitting in the clinic, against the 37 and 47 crowns. Red marks designate the centric platforms. The blue marks designate the protrusive ramps for sagittal directed protrusive rises in early to mid-paths. The white marks designate the lateral guidance/restrictive ridges to prevent distalization of the mandible in lateral movement. The length of the molar rise path after modification was 2.5-3 mm from the centric stop to the molar rise landing pad. Fig 4. Lateral view of a right first molar rise occlusal reconstruction at an increased vertical dimension for a dolichofacial TMD patient, in 2013. Biodesigning the zirconia crowns on all first molars focused on designing a long lateral path by: deleting the 46 distal cusp, increasing the height of the 46 distobuccal cusp by 0.5-0.75 mm and tilting this cusp more lingual, elongating the 16 distobuccal cusp by 1.25-1.5 mm and positioning it more buccal with a flat landing pad. At edge-to-edge molar rise, the disclusion of the second molars was a 1.5-2 mm clearance with a vertico-lateral mandibular vector and a generous lateral guidance path of about 3.5 mm for this extreme clencher/grinder. Patient Gender Age Patient notes Self-reported improvement (%) Years Splint No. OST = Occlusal Splint Therapy, Stage 1 Stage 2 Stage 3 Final follow up wearing OE = Occlusal Equilibration, (OST) (OST + (OST + at MG = Molar Guidance OE) OE + MG) follow up 1 M 32 TMJ pain R, masseter pain and spasm R & L, clicking R, 30 60 100 100 9 Yes restricted opening 35 mm, molar rise crown 46 6 F 39 TMJ intractable pain R & L, otalgia, restricted opening 23 mm, 10 20 100 100 17 Yes 2-3 mm posterior slide, temporal & masseter pain, migraines, MRI antero-medial non-reducing discs R & L, molar rise crowns 17, 27, 37 and 47 for occlusal reconstruction 161 F 42 TMJ pain R & L, clicking R & L, masseter pain R & L, “puffy” 60 70 100 100 9 No masseters, restricted opening 34 mm, molar rise crowns 37 and 47 Table 1. Three dolichofacial patients that completed Full Occlusal Therapy sequentially with Occlusal Splint Therapy, Occlusal Equilibration and Molar Guidance
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